Quantitative analysis of airway obstruction in lymphangioleiomyomatosis

Lymphangioleiomyomatosis (LAM) is a rare, cystic lung disease with progressive pulmonary function loss caused by progressively proliferating LAM cells. The degree of airway obstruction has not been well investigated within the pathogenesis of LAM. Using a combination of ex vivo computed tomography (CT), microCT and histology, the site and nature of airway obstruction in LAM explant lungs was compared with matched control lungs (n=5 each). The total number of airways per generation, total airway counts, terminal bronchioles number and surface density were compared in LAM versus control. Ex vivo CT analysis demonstrated a reduced number of airways from generation 7 on (p<0.0001) in LAM compar…

Lung microenvironments and disease progression in fibrotic hypersensitivity pneumonitis

Rationale: Fibrotic hypersensitivity pneumonitis (fHP) is an interstitial lung disease caused by sensitization to an inhaled allergen. Objectives: To identify the molecular determinants associated with progression of fibrosis. Methods: Nine fHP explant lungs and six unused donor lungs (as controls) were systematically sampled (4 samples/lung). According to microcomputed tomography measures, fHP cores were clustered into mild, moderate, and severe fibrosis groups. Gene expression profiles were assessed using weighted gene co-expression network analysis, xCell, gene ontology, and structure enrichment analysis. Gene expression of the prevailing molecular traits was also compared with idiopathi…

Micromechanical forces regulate vascular patterning in the chick chorioallantoic membrane (15.3)

Glycoconjugate expression in the extracellular matrix of the mouse lung (87.7)

External Volume Expansion Increases Subcutaneous Thickness, Cell Proliferation, and Vascular Remodeling in a Murine Model

Background Fat grafting is a powerful tool for soft-tissue reconstruction; however, the science behind recipient bed preparation has not been thoroughly explored. External volume expansion using suction before fat grafting has been used clinically to improve reliability and consistency of graft survival. The authors developed a murine model to investigate the underlying mechanism of external volume expansion. Methods The authors created an external volume expansion device using a soft-silicone dome connected to a vacuum source (25 mmHg) to treat the dorsum of mice, and the response was compared with treatment with an occlusive dressing. Treated areas were monitored with magnetic resonance i…

Polyphosphate, the physiological metabolic fuel for corneal cells: a potential biomaterial for ocular surface repair

The regeneration of the epithelium, covering the avascular cornea, involves the processes of differentiation, proliferation and migration of cells originating from the corneal epithelial stem cells. We ask the question if these energy-consuming processes can be fueled by the physiological, inorganic polyphosphate (polyP), the main energy storage/donor molecule in the extracellular space. The ex vivo results reveal that addition of polyP, in the form of soluble Na-polyP, to the culture medium elicits a strong stimulatory effect on cell viability/growth and migration of corneal epithelial cells. Microscopic analyses of partially denuded cornea specimens show that in the presence of polyP, but…

Impact of single-dose application of TGF-β, copper peptide, stanozolol and ascorbic acid in hydrogel on midline laparatomy wound healing in a diabetic mouse model.

Despite numerous advances and improvements in surgical techniques the incidence of incisional hernias after laparotomy remains high. The aim of this study was to investigate possible effects of single application of ascorbic acid, stanozolol, a synthetic anabolic steroid, copper peptide and transforming growth factor-β (TGF-β) on laparotomy wound healing in an incisional wound model in diabetic mice. After diabetes induction with streptozotozin in Balb-c mice, midline laparatomies were carried out. Closure of the linea alba was followed by single-dose application of the agents dissolved in a hydrogel before skin closure. The functional outcome was assessed in terms of maximum tensile streng…

A multiscale X-ray phase-contrast tomography dataset of whole human left lung

ABSTRACTTechnological advancements in X-ray imaging using bright and coherent synchrotron sources now allows to decouple sample size and resolution, while maintaining high sensitivity to the microstructure of soft, partially dehydrated tissues. The recently developed imaging technique, hierarchical phase-contrast tomography, is a comprehensive approach to address the challenge of organ-scale (up to tens of centimeters) soft tissue imaging with resolution and sensitivity down to the cellular level. Using this technique, we imaged ex vivo an entire human left lung at an isotropic voxel size of 25.08 μm along with local zooms down to 6.05 - 6.5 μm and 2.45 - 2.5 μm in voxel size. The high tiss…

Bifunctional dentifrice: Amorphous polyphosphate a regeneratively active sealant with potent anti- Streptococcus mutans activity

Abstract Objective In this study we demonstrate that inorganic polyphosphate (polyP) exhibits a dual protective effect on teeth: it elicits a strong antibacterial effect against the cariogenic bacterium Streptococcus mutans and, in form of amorphous calcium polyP microparticles (size of 100–400 nm), it efficiently reseals cracks/fissures in the tooth enamel and dentin. Methods Three different formulations of amorphous polyP microparticles (Ca-polyP, Zn-polyP and Sr-polyP) were prepared. Results Among the different polyP microparticles tested, the Ca-polyP microparticles, as a component of a newly developed formulation of a dentifrice, turned out to be most effective in inhibiting growth of …

Plexiform Vasculopathy in Chronic Thromboembolic Pulmonary Hypertension

Intussusceptive Remodeling of Vascular Branch Angles in Chemically-Induced Murine Colitis

Intussusceptive angiogenesis is a developmental process linked to both blood vessel replication and remodeling in development. To investigate the prediction that the process of intussusceptive angiogenesis is associated with vessel angle remodeling in adult mice, we systematically evaluated corrosion casts of the mucosal plexus in mice with trinitrobenzesulphonic acid (TNBS)-induced and dextran sodium sulfate (DSS)-induced colitis. The mice demonstrated a significant decrease in vessel angles in both TNBS-induced and DSS-induced colitis within 4 weeks of the onset of colitis (p<.001). Corrosion casts 28–30 days after DSS treatment were studied for a variety of detailed morphometric changes.…

Migration of CD11b+ accessory cells during murine lung regeneration

In many mammalian species, the removal of one lung leads to growth of the remaining lung to near-baseline levels. In studying post-pneumonectomy mice, we used morphometric measures to demonstrate neoalveolarization within 21 days of pneumonectomy. Of note, the detailed histology during this period demonstrated no significant pulmonary inflammation. To identify occult blood-borne cells, we used a parabiotic model (wild-type/GFP) of post-pneumonectomy lung growth. Flow cytometry of post-pneumonectomy lung digests demonstrated a rapid increase in the number of cells expressing the hematopoietic membrane molecule CD11b; 64.5% of the entire GFP(+) population were CD11b(+). Fluorescence microscop…

Priming with a combination of proangiogenic growth factors improves wound healing in normoglycemic mice

Growth factors and/or angiogenic factors are supposed to improve wound healing. The aim of our study was to evaluate the effects of subcutaneous pretreatment with combinatory proangiogenic factors on wound closure, mechan - ical properties, vessel density and morphology. Twenty-eight Balb/c mice were divided equally into two groups. A mixture of VEGF (35.0 µg), bFGF (2.5 µg) and P dGF (3.5 µg) was administered subcutaneously 3, 5 and 7 days to 14 mice before full thickness skin punch biopsy wounding, whereas 14 control animals received three injections of 0.2 ml saline solution. Wound sizes were assessed daily and the repaired tissues were harvested 7 days after complete wound closure. Comp…

Functional Mechanics of a Pectin-Based Pleural Sealant after Lung Injury.

Pleural injury and associated air leaks are a major influence on patient morbidity and healthcare costs after lung surgery. Pectin, a plant-derived heteropolysaccharide, has recently demonstrated potential as an adhesive binding to the glycocalyx of visceral mesothelium. Since bioadhesion is a process likely involving the interpenetration of the pectin-based polymer with the glycocalyx, we predicted that the pectin-based polymer may also be an effective sealant for pleural injury. To explore the potential role of an equal (weight%) mixture of high-methoxyl pectin and carboxymethylcellulose as a pleural sealant, we compared the yield strength of the pectin-based polymer to commonly available…

Priming with proangiogenic growth factors and endothelial progenitor cells improves revascularization in linear diabetic wounds

In the present study, we investigated whether proangiogenic growth factors and endothelial progenitor cells (EPCs) induce favourable effects on cutaneous incisional wound healing in diabetic mice. The proangiogenic effects of human EPCs were initially analyzed using a HUVEC in vitro angiogenesis assay and an in vivo Matrigel assay in nude mice (n=12). For the diabetic wound model, 48 Balb/c mice with streptozotocin (STZ)-induced diabetes were divided randomly into 4 groups (12 mice in each group). Subsequently, 3, 5 and 7 days before a 15-mm full-thickness incisional skin wound was set, group 1 was pre-treated subcutaneously with a mixture of vascular endothelial growth factor (VEGF)/basic …

Structural Remodeling of the Post‐pneumonectomy Lung is Characterized by Septal Retraction and Alveolar Duct Dilation

Murine pneumonectomy (PNX) is an established model of adult compensatory lung growth, involving structural remodeling of the peripheral parenchyma. Following left PNX, positron emission tomography and computerized tomography have demonstrated heterogeneous growth patterns within the remaining right lung. To characterize the structural changes associated with these observations, we analyzed histological sections of the right lung between 3 and 22 days after PNX. Within 3 days of PNX, alveolar septae were significantly shorter (p<0.05) in a majority of alveolar ducts, while septal angle remained unchanged. Septal retraction resulted in an apparent dilation of the alveolar duct with a signific…

The bronchial circulation in COVID-19 pneumonia.

American journal of respiratory and critical care medicine : AJRCCM 205(1), 121-125 (2022). doi:10.1164/rccm.202103-0594IM

Fabrication of amorphous strontium polyphosphate microparticles that induce mineralization of bone cells in vitro and in vivo.

Abstract Here we describe the fabrication process of amorphous strontium-polyphosphate microparticles (“Sr-a-polyP-MP”). The effects of these particles on growth and gene expression were investigated with SaOS-2 cells as well as with human mesenchymal stem cells (MSC) and compared with those particles prepared of amorphous calcium-polyphosphate (“Ca-a-polyP-MP”) and of strontium salt. The results revealed a markedly higher stimulation of growth of MSC by “Sr-a-polyP-MP” compared to “Ca-a-polyP-MP” and a significant increase in mineralization of SaOS-2 cells, as well as an enhanced upregulation of the expression of the genes encoding for alkaline phosphatase and the bone morphogenetic protei…

Impact of platelet rich plasma and adipose stem cells on lymphangiogenesis in a murine tail lymphedema model.

Abstract Background Lymphedema is an underdiagnosed pathology which in industrialized countries mainly affects cancer patients that underwent lymph node dissection and/or radiation. Currently no effective therapy is available so that patients' life quality is compromised by swellings of the concerned body region. This unfortunate condition is associated with body imbalance and subsequent osteochondral deformations and impaired function as well as with an increased risk of potentially life threatening soft tissue infections. Methods The effects of PRP and ASC on angiogenesis (anti-CD31 staining), microcirculation (Laser Doppler Imaging), lymphangiogenesis (anti-LYVE1 staining), microvascular…

Elastin Cables Define the Axial Connective Tissue System in the Murine Lung

The axial connective tissue system is a fiber continuum of the lung that maintains alveolar surface area during changes in lung volume. Although the molecular anatomy of the axial system remains undefined, the fiber continuum of the lung is central to contemporary models of lung micromechanics and alveolar regeneration. To provide a detailed molecular structure of the axial connective tissue system, we examined the extracellular matrix of murine lungs. The lungs were decellularized using a 24 hr detergent treatment protocol. Systematic evaluation of the decellularized lungs demonstrated no residual cellular debris; morphometry demonstrated a mean 39 ± 7% reduction in lung dimensions. Scanni…

Mechanostructural adaptations preceding postpneumonectomy lung growth

In many species, pneumonectomy results in compensatory growth in the remaining lung. Although the late mechanical consequences of murine pneumonectomy are known, little is known about the anatomic adaptations and respiratory mechanics during compensatory lung growth. To investigate the structural and mechanical changes during compensatory growth, mice were studied for 21 days after left pneumonectomy using microCT and respiratory system impedance (FlexiVent). Anatomic changes after left pneumonectomy included minimal mediastinal shift or chestwall remodeling, but significant displacement of the heart and cardiac lobe. Mean displacement of the cardiac lobe centroid was 5.2 ± 0.8 mm. Lung imp…

Priming with a Combination of Proangiogenic Growth Factors Enhances Wound Healing in Streptozotocin-Induced Diabetes in Mice

&lt;i&gt;Background:&lt;/i&gt; Numerous proangiogenic growth factors have been shown to improve impaired wound healing. This study evaluated the effects of subcutaneous pretreatment with a combination of proangiogenic growth factors on wound closure, mechanical properties, vessel density, and morphology. &lt;i&gt;Methods:&lt;/i&gt; Thirty-six Balb/c mice with streptozotocin-induced diabetes were divided into 3 groups. A mixture of VEGF (35.0 µg), bFGF (2.5 µg), and PDGF (3.5 µg) was administered subcutaneously 3, 5, and 7 days prior to wounding in the first group, whereas the second group received three doses of 3.5 µg PDGF. Wound sizes were assessed daily and the repaired tissues were harv…

The Effect of Calcium on the Cohesive Strength and Flexural Properties of Low-Methoxyl Pectin Biopolymers.

Abstract: Pectin binds the mesothelial glycocalyx of visceral organs, suggesting its potential role as a mesothelial sealant. To assess the mechanical properties of pectin films, we compared pectin films with a less than 50% degree of methyl esterification (low-methoxyl pectin, LMP) to films with greater than 50% methyl esterification (high-methoxyl pectin, HMP). LMP and HMP polymers were prepared by step-wise dissolution and high-shear mixing. Both LMP and HMP films demonstrated a comparable clear appearance. Fracture mechanics demonstrated that the LMP films had a lower burst strength than HMP films at a variety of calcium concentrations and hydration states. The water content also influe…

Evidence for pleural epithelial-mesenchymal transition in murine compensatory lung growth

In many mammals, including rodents and humans, removal of one lung results in the compensatory growth of the remaining lung; however, the mechanism of compensatory lung growth is unknown. Here, we investigated the changes in morphology and phenotype of pleural cells after pneumonectomy. Between days 1 and 3 after pneumonectomy, cells expressing α-smooth muscle actin (SMA), a cytoplasmic marker of myofibroblasts, were significantly increased in the pleura compared to surgical controls (p < .01). Scanning electron microscopy of the pleural surface 3 days post-pneumonectomy demonstrated regions of the pleura with morphologic features consistent with epithelial-mesenchymal transition (EMT); nam…

Amorphous polyphosphate/amorphous calcium carbonate implant material with enhanced bone healing efficacy in a critical-size defect in rats

In this study the effect of amorphous calcium carbonate (ACC) microparticles and amorphous calcium polyphosphate (polyP) microparticles (termed aCa-polyP-MP) on bone mineral forming cells/tissue was investigated in vitro and in vivo. The ACC particles (termed ACC-P10-MP) were prepared in the presence of Na-polyP. Only the combinations of polyP and ACC microparticles enhanced the proliferation rate of human mesenchymal stem cells (MSCs). Gene expression studies revealed that ACC causes an upregulation of the expression of the cell membrane-associated carbonic anhydrase IX (CA IX; formation of ACC), while the transcript level of the alkaline phosphatase (ALP; liberation of orthophosphate from…

Pressure-decay testing of pleural air leaks in intact murine lungs: evidence for peripheral airway regulation.

Abstract The critical care management of pleural air leaks can be challenging in all patients, but particularly in patients on mechanical ventilation. To investigate the effect of central airway pressure and pleural pressure on pulmonary air leaks, we studied orotracheally intubated mice with pleural injuries. We used clinically relevant variables – namely, airway pressure and pleural pressure – to investigate flow through peripheral air leaks. The model studied the pleural injuries using a pressure‐decay maneuver. The pressure‐decay maneuver involved a 3 sec ramp to 30 cmH20 followed by a 3 sec breath hold. After pleural injury, the pressure‐decay maneuver demonstrated a distinctive airway…

Morphogenetically-Active Barrier Membrane for Guided Bone Regeneration, Based on Amorphous Polyphosphate

We describe a novel regeneratively-active barrier membrane which consists of a durable electrospun poly(ε-caprolactone) (PCL) net covered with a morphogenetically-active biohybrid material composed of collagen and inorganic polyphosphate (polyP). The patch-like fibrous collagen structures are decorated with small amorphous polyP nanoparticles (50 nm) formed by precipitation of this energy-rich and enzyme-degradable (alkaline phosphatase) polymer in the presence of calcium ions. The fabricated PCL-polyP/collagen hybrid mats are characterized by advantageous biomechanical properties, such as enhanced flexibility and stretchability with almost unaltered tensile strength of the PCL net. The pol…

Branch‐Chain Interpenetration of the Mesothelial Glycocalyx with Naturally‐Occurring Biopolymers

Adnectin CT-322 inhibits tumor growth and affects microvascular architecture and function in Colo205 tumor xenografts

Antiangiogenesis has become a promising pillar in modern cancer therapy. This study investigates the antiangiogenic effects of the PEGylated Adnectin™, CT-322, in a murine Colo-205 xenograft tumor model. CT-322 specifically binds to and blocks vascular endothelial growth factor receptor (VEGFR-2). Adnectins are a novel class of targeted biologics engineered from the 10th domain of human fibronectin. CT-322 treated tumors exhibited a significant reduction in tumor growth of 69%, a 2.8 times lower tumor surface area and fewer necrotic areas. Control tumors showed a 2.36-fold higher microvessel density (MVD) and a 2.42 times higher vessel volume in corrosion casts. The vascular architecture in…

Multiscale three-dimensional imaging of intact human organs down to the cellular scale using hierarchical phase-contrast tomography

ABSTRACTHuman organs are complex, three-dimensional and multiscale systems. Spatially mapping the human body down through its hierarchy, from entire organs to their individual functional units and specialised cells, is a major obstacle to fully understanding health and disease. To meet this challenge, we developed hierarchical phase-contrast tomography (HiP-CT), an X-ray phase propagation technique utilising the European Synchrotron Radiation Facility’s Extremely Brilliant Source: the world’s first high-energy 4th generation X-ray source. HiP-CT enabled three-dimensional and non-destructive imaging at near-micron resolution in soft tissues at one hundred thousand times the voxel size whilst…

Single-Cell Transcriptional Profiling of Cells Derived From Regenerating Alveolar Ducts

Lung regeneration occurs in a variety of adult mammals after surgical removal of one lung (pneumonectomy). Previous studies of murine post-pneumonectomy lung growth have identified regenerative “hotspots” in subpleural alveolar ducts; however, the cell-types participating in this process remain unclear. To identify the single cells participating in post-pneumonectomy lung growth, we used laser microdissection, enzymatic digestion and microfluidic isolation. Single-cell transcriptional analysis of the murine alveolar duct cells was performed using the C1 integrated fluidic circuit (Fluidigm) and a custom PCR panel designed for lung growth and repair genes. The multi-dimensional data set was …

A bio-imitating approach to fabricate an artificial matrix for cartilage tissue engineering using magnesium-polyphosphate and hyaluronic acid

Here we describe an artificial cartilage-like material based on a hyaluronic acid-Mg/Ca-polyphosphate paste (HA-aMg/Ca-polyP-p) that is fabricated from a water-soluble Na-salt of energy-rich inorganic polyphosphate (polyP) and soluble hyaluronic acid in the presence of water-insoluble CaCO3. The resulting material, after conversion of Na-polyP into the less soluble Mg/Ca-salt consisting of amorphous Mg/Ca-polyP microparticles, was found to mimic the physiological cartilage tissue and to bind Ca2+ ions present in the synovial fluid. After the Mg2+/Ca2+ exchange and water extrusion, the polyP becomes more stable, but is still susceptible to hydrolytic cleavage by the alkaline phosphatase (ALP…

Enhancement of Wound Healing in Normal and Diabetic Mice by Topical Application of Amorphous Polyphosphate. Superior Effect of a Host⁻Guest Composite Material Composed of Collagen (Host) and Polyphosphate (Guest).

The effect of polyphosphate (polyP) microparticles on wound healing was tested both in vitro and in a mice model in vivo. Two approaches were used: pure salts of polyphosphate, fabricated as amorphous microparticles (MPs, consisting of calcium and magnesium salts of polyP, “Ca–polyp-MPs” and “Mg–polyp-MPs”), and host–guest composite particles, prepared from amorphous collagen (host) and polyphosphate (guest), termed “col/polyp-MPs”. Animal experiments with polyP on healing of excisional wounds were performed using both normal mice and diabetic mice. After a healing period of 7 days “Ca–polyp-MP” significantly improved re-epithelialization in normal mice from 31% (control) to 72% (polyP micr…

Biomimetic transformation of polyphosphate microparticles during restoration of damaged teeth.

Abstract Objective In the present study, we investigated the fusion process between amorphous microparticles of the calcium salt of the physiological polymer comprising orthophosphate units, of inorganic polyphosphate (polyP), and enamel. Methods This polymer was incorporated as an ingredient into toothpaste and the fusion process was studied by electron microscopy and by synchrotron-based X-ray tomography microscopy (SRXTM) techniques. Results The data showed that toothpaste, supplemented with the amorphous Ca-polyP microparticles (aCa-polyP-MP), not only reseals tooth defects on enamel, like carious lesions, and dentin, including exposed dentinal tubules, but also has the potential to ind…

Investigation of inhibitory effects on EPC-mediated neovascularization by different bisphosphonates for cancer therapy.

Bisphosphonates (BPs) are potent drugs, used in metastatic cancer-like prostate or breast carcinoma. In recent studies, besides reduced bone remodeling, influences on angiogenesis and neovascularization were reported. Since BPs have the tendency to accumulate in the bones, the biological effect of various nitrogen- and non-nitrogen BPs on endothelial progenitor cells (EPCs) that originated from bone marrow and mobilized under physiological and pathophysiological conditions, such as tumor neovascularization, was investigated. EPCs subsequent to 72-h treatment with different concentrations of bisphosphonates comprised the non-nitrogen-containing BP clodronate and the nitrogen-containing BPs i…

Sprouting and intussusceptive angiogenesis in postpneumonectomy lung growth: mechanisms of alveolar neovascularization

In most rodents and some other mammals, the removal of one lung results in compensatory growth associated with dramatic angiogenesis and complete restoration of lung capacity. One pivotal mechanism in neoalveolarization is neovascularization, because without angiogenesis new alveoli can not be formed. The aim of this study is to image and analyze three-dimensionally the different patterns of neovascularization seen following pneumonectomy in mice on a sub-micron-scale. C57/BL6 mice underwent a left-sided pneumonectomy. Lungs were harvested at various timepoints after pneumonectomy. Volume analysis by microCT revealed a striking increase of 143 percent in the cardiac lobe 14 days after pneum…

Abstract B09: Nintedanib inhibits tumor and vessel growth and leads to vascular normalization in A549-NSCLC-xenografts

Abstract Angiogenesis plays a major role in the growth and progression of non-small-cell lung cancer (NSCLC). The triple angiokinase inhibitor nintedanib is a potent inhibitor of the receptor tyrosine kinases FGFR-1, 2, 3, PDGFR-α and β, VEGFR-1, 2, 3. and Flt-3. as well as of non-receptor tyrosine kinases like Src, Lyn and Lck by occupying the intracellular ATP-binding pocket. In the pivotal LUME-Lung 1 trial Nintedanib plus docetaxel has proven an overall survival benefit over docetaxel monotherapy in second-line treatment of non-small-cell lung cancer of adenocarcinoma. The aim of this study was to analyse treatment induced vascular normalization of nintedanib, bevacizumab and docetaxel …

Three-dimensional image analytical detection of intussusceptive pillars in murine lung

A variety of diseases can lead to loss of lung tissue. Currently, this can be treated only symptomatically. In mice, a complete compensatory lung growth within 21 days after resection of the left lung can be observed. Understanding and transferring this concept of compensatory lung growth to humans would greatly improve therapeutic options. Lung growth is always accompanied by a process called angiogenesis forming new capillary blood vessels from preexisting ones. Among the processes during lung growth, the formation of transluminal tissue pillars within the capillary vessels (intussusceptive pillars) is observed. Therefore, pillars can be understood as an indicator for active angiogenesis …

Fabrication of a new physiological macroporous hybrid biomaterial/bioscaffold material based on polyphosphate and collagen by freeze-extraction

We describe the fabrication of a new scaffold, an inorganic–organic hybrid biomaterial, consisting of the physiological polymers: the inorganic polymer polyphosphate (polyP), as well as the organic macromolecules collagen and chondroitin sulfate. The polyP polymer is composed of multiple phosphate orthophosphate units linked together by high-energy phosphoanhydride bonds. Chondroitin sulfate has been included due to its hydrogel-forming properties. In the presence of Ca2+ ions, the randomly coiled polyP reorganizes together with collagen and chondroitin sulfate to linear molecules which undergo hardening. This scaffold is deposited as amorphous Ca–polyP nanoparticles (size ≈20–40 nm large) …

Structural heteropolysaccharides as air-tight sealants of the human pleura

Pulmonary "air leaks," typically the result of pleural injury caused by lung surgery or chest trauma, result in the accumulation of air in the pleural space (pneumothorax). Air leaks are a major source of morbidity and prolonged hospitalization after pulmonary surgery. Previous work has demonstrated structural heteropolysaccharide (pectin) binding to the mouse pleural glycocalyx. The similar lectin-binding characteristics and ultrastructural features of the human and mouse pleural glycocalyx suggested the potential application of these polymers in humans. To investigate the utility of pectin-based polymers, we developed a simulacrum using freshly obtained human pleura. Pressure-decay leak t…

Structural Heteropolysaccharide Adhesion to the Glycocalyx of Visceral Mesothelium

Bioadhesives are biopolymers with potential applications in wound healing, drug delivery, and tissue engineering. Pectin, a plant-based heteropolysaccharide, has recently demonstrated potential as a mucoadhesive in the gut. Since mucoadhesion is a process likely involving the interpenetration of the pectin polymer with mucin chains, we hypothesized that pectin may also be effective at targeting the glycocalyx of the visceral mesothelium. To explore the potential role of pectin as a mesothelial bioadhesive, we studied the interaction of various pectin formulations with the mesothelium of the lung, liver, bowel, and heart. Tensile strength, peel strength, and shear resistance of the bioadhesi…

Parvovirus B19-induced angiogenesis in fulminant myocarditis

Acceleration of image filtering algorithms for 3D visualization of murine lungs using dataflow engines

Image filtering is one of the most common and important tasks in image processing applications. In this paper, image processing using a mean filtering algorithm combined with thresholding and binarization algorithms for the 3D visualization and analysis of murine lungs is explained. These algorithms are then mapped on the Maxler's MAX2336B Dataflow Engine (DFE) to significantly increase calculation speed. Several different DFE configurations were tested and each yielded different performance characteristics. Optimal algorithm calculation speed was up to 30 fold baseline calculation speed.

Uptake of polyphosphate microparticles in vitro (SaOS-2 and HUVEC cells) followed by an increase of the intracellular ATP pool size

Recently two approaches were reported that addressed a vitally important problem in regenerative medicine, i. e. the successful treatment of wounds even under diabetic conditions. Accordingly, these studies with diabetic rabbits [Sarojini et al. PLoS One 2017, 12(4):e0174899] and diabetic mice [Müller et al. Polymers 2017, 9, 300] identified a novel (potential) target for the acceleration of wound healing in diabetes. Both studies propose a raise of the intracellular metabolic energy status via exogenous administration either of ATP, encapsulated into lipid vesicles, or of polyphosphate (polyP) micro-/nanoparticles. Recently this physiological polymer, polyP, was found to release metabolic …

In Situ Polyphosphate Nanoparticle Formation in Hybrid Poly(vinyl alcohol)/Karaya Gum Hydrogels: A Porous Scaffold Inducing Infiltration of Mesenchymal Stem Cells

Abstract The preparation and characterization of a porous hybrid cryogel based on the two organic polymers, poly(vinyl alcohol) (PVA) and karaya gum (KG), into which polyphosphate (polyP) nanoparticles have been incorporated, are described. The PVA/KG cryogel is prepared by intermolecular cross‐linking of PVA via freeze‐thawing and Ca2+‐mediated ionic gelation of KG to form stable salt bridges. The incorporation of polyP as amorphous nanoparticles with Ca2+ ions (Ca‐polyP‐NP) is achieved using an in situ approach. The polyP constituent does not significantly affect the viscoelastic properties of the PVA/KG cryogel that are comparable to natural soft tissue. The exposure of the Ca‐polyP‐NP w…

The Adult Sprague-Dawley Sugen-Hypoxia Rat Is Still "the One:" A Model of Group 1 Pulmonary Hypertension: Reply to Le Cras and Abman

To the editor: Kojonazarov et al. recently reported severe emphysema in the SU5416/Hypoxia (SuHx) rat model of pulmonary hypertension (1). The authors found that adult male Wistar Kyoto (WKY) rats had increased air-to-tissue ratio as judged by non-gated in vivo micro-computed tomography (CT), and an increased mean linear intercept (MLI) as surrogate of emphysema (1, 2). Le Cras and Abman now responded to the Kojonazarov report by underlining the “important role of the developmental timing of disrupted VEGF signaling” (3). They cite earlier studies conducted on the ovine fetus showing that VEGF inhibition caused vascular remodeling, reduction in vascular/airway growth, and neonatal pulmonary…

Visualizing pectin polymer-polymer entanglement produced by interfacial water movement.

In this report, we investigated the physical conditions for creating pectin polymer-polymer (homopolymer) entanglement. The potential role of water movement in creating pectin entanglement was investigated by placing water droplets-equivalent to the water content of two gel phase films-between two glass phase films and compressing the films at variable probe velocities. Slow probe velocity (0.5 mm/sec) demonstrated no significant debonding. Corresponding videomicroscopy demonstrated an occasional water bridge, but no evidence of stranding or polymer entanglement. In contrast, fast probe velocity (5 mm/sec) resulted in 1) an increase in peak adhesion strength, 2) a progressive debonding curv…

Role of ATP during the initiation of microvascularization: acceleration of an autocrine sensing mechanism facilitating chemotaxis by inorganic polyphosphate

The in vitro tube formation assay with human umbilical vein endothelial cells (HUVEC) was applied to identify the extra- and intracellular sources of metabolic energy/ATP required for cell migration during the initial stage of microvascularization. Extracellularly, the physiological energy-rich polymer, inorganic polyphosphate (polyP), applied as biomimetic amorphous calcium polyP microparticles (Ca-polyP-MP), is functioning as a substrate for ATP generation most likely via the combined action of the alkaline phosphatase (ALP) and the adenylate kinase (AK). The linear Ca-polyP-MP with a size of 40 phosphate units, close to the polyP in the acidocalcisomes in the blood platelets, were found …

Alveolar Epithelial Dynamics in Postpneumonectomy Lung Growth

The intimate anatomic and functional relationship between epithelial cells and endothelial cells within the alveolus suggests the likelihood of a coordinated response during postpneumonectomy lung growth. To define the population dynamics and potential contribution of alveolar epithelial cells to alveolar angiogenesis, we studied alveolar Type II and I cells during the 21 days after pneumonectomy. Alveolar Type II cells were defined and isolated by flow cytometry using a CD45(-) , MHC class II(+) , phosphine(+) phenotype. These phenotypically defined alveolar Type II cells demonstrated an increase in cell number after pneumonectomy; the increase in cell number preceded the increase in Type …

Alveolar macrophage dynamics in murine lung regeneration

In most mammalian species, the removal of one lung results in dramatic compensatory growth of the remaining lung. To investigate the contribution of alveolar macrophages (AMs) to murine post-pneumonectomy lung growth, we studied bronchoalveolar lavage (BAL)-derived AM on 3, 7, 14 and 21 days after left pneumonectomy. BAL demonstrated a 3.0-fold increase in AM (CD45(+), CD11b(-), CD11c(+), F4/80(+), Gr-1(-)) by 14 days after pneumonectomy. Cell cycle flow cytometry of the BAL-derived cells demonstrated an increase in S + G2 phase cells on days 3 (11.3 ± 2.7%) and 7 (12.1 ± 1.8%) after pneumonectomy. Correspondingly, AM demonstrated increased expression of VEGFR1 and MHC class II between days…

A novel minimally invasive, dorsolateral, tubular partial odontoidectomy and autologous bone augmentation to treat dens pseudarthrosis: cadaveric, 3D virtual simulation study and technical report.

OBJECTIVE The goal of this study was to demonstrate the clinical and technical nuances of a minimally invasive, dorsolateral, tubular approach for partial odontoidectomy, autologous bone augmentation, and temporary C1–2 fixation to treat dens pseudarthrosis. METHODS A cadaveric feasibility study, a 3D virtual reality reconstruction study, and the subsequent application of this approach in 2 clinical cases are reported. Eight procedures were completed in 4 human cadavers. A minimally invasive, dorsolateral, tubular approach for odontoidectomy was performed with the aid of a tubular retraction system, using a posterolateral incision and an oblique approach angle. Fluoroscopy and postprocedur…

Biomechanical and histological evaluation of abdominal wall compliance with intraperitoneal onlay mesh implants in rabbits: A comparison of six different state-of-the-art meshes

Abstract Background An ideal prosthetic mesh for incisional hernia repair should mimic the anisotropic compliance of the abdominal wall, and at lower loads should exhibit higher distensibility without impairment of safety at higher loads. This study evaluated the biomechanical properties of six meshes in a rabbit model. Methods New Zealand white rabbits were used for this study. Two meshes of the same brand (Ethicon Physiomesh™, Bard Composix ® L/P, Gore Dualmesh ® , Bard Sepramesh ® , Ethicon Proceed ® or Parietex™ Composite) were implanted into each animal for assessment of intra-abdominal hernia repair, with a total of ten meshes per group. Twelve weeks after implantation, the abdominal …

Amplified morphogenetic and bone forming activity of amorphous versus crystalline calcium phosphate/polyphosphate.

Amorphous Ca-phosphate (ACP) particles stabilized by inorganic polyphosphate (polyP) were prepared by co-precipitation of calcium and phosphate in the presence of polyP (15% [w/w]). These hybrid nanoparticles showed no signs of crystallinity according to X-ray diffraction analysis, in contrast to the particles obtained at a lower (5% [w/w]) polyP concentration or to hydroxyapatite. The ACP/15% polyP particles proved to be a suitable matrix for cell growth and attachment and showed pronounced osteoblastic and vasculogenic activity in vitro. They strongly stimulated mineralization of the human osteosarcoma cell line SaOS-2, as well as cell migration/microvascularization, as demonstrated in th…

Flower lose, a cell fitness marker, predicts COVID‐19 prognosis

Abstract Risk stratification of COVID‐19 patients is essential for pandemic management. Changes in the cell fitness marker, hFwe‐Lose, can precede the host immune response to infection, potentially making such a biomarker an earlier triage tool. Here, we evaluate whether hFwe‐Lose gene expression can outperform conventional methods in predicting outcomes (e.g., death and hospitalization) in COVID‐19 patients. We performed a post‐mortem examination of infected lung tissue in deceased COVID‐19 patients to determine hFwe‐Lose’s biological role in acute lung injury. We then performed an observational study (n = 283) to evaluate whether hFwe‐Lose expression (in nasopharyngeal samples) could accu…

Morphomolecular motifs of pulmonary neoangiogenesis in interstitial lung diseases

The pathogenetic role of angiogenesis in interstitial lung diseases (ILDs) is controversial. This study represents the first investigation of the spatial complexity and molecular motifs of microvascular architecture in important subsets of human ILD. The aim of our study was to identify specific variants of neoangiogenesis in three common pulmonary injury patterns in human ILD.We performed comprehensive and compartment-specific analysis of 24 human lung explants with usual intersitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP) and alveolar fibroelastosis (AFE) using histopathology, microvascular corrosion casting, micro-comupted tomography based volumetry and gene expression…

Dynamic contrast‐enhanced magnetic resonance imaging for monitoring angiogenesis during bone regeneration – a randomized pilot study in rabbits

Molecular similarities and differences from human pulmonary fibrosis and corresponding mouse model: MALDI imaging mass spectrometry in comparative medicine

Animal models can reproduce some model-specific aspects of human diseases, but some animal models translate poorly or fail to translate to the corresponding human disease. Here, we develop a strategy to systematically compare human and mouse tissues, and conduct a proof-of-concept experiment to identify molecular similarities and differences using patients with idiopathic pulmonary fibrosis and a bleomycin-induced fibrosis mouse model. Our novel approach employs high-throughput tissue microarrays (TMAs) of humans and mice, high-resolution matrix-assisted laser desorption/ionization-Fourier transform-ion cyclotron resonance-mass spectrometry imaging (MALDI-FT-ICR-MSI) to spatially resolve ma…

Noninvasive Flap Preconditioning by Foam-Mediated External Suction Improves the Survival of Fasciocutaneous Axial-Pattern Flaps in a Type 2 Diabetic Murine Model

Background Advances in reconstructive surgery are leading to an increased number of flaps at risk for ischemic necrosis, because of either intrinsic (e.g., larger flap size) or extrinsic (e.g., diabetes) factors. Methods to preoperatively improve flap vascularity and limit postoperative ischemia are lacking. Noninvasive suction, using either a macrodeformational silicone cup interface (external volume expansion) or a microdeformational polyurethane foam interface (foam-mediated external volume expansion), has been shown to induce angiogenesis in tissues. The authors investigated whether the preoperative use of external volume expansion/foam-mediated external volume expansion improves flap s…

Angiogenesis in Wounds Treated by Microdeformational Wound Therapy.

BACKGROUND:: Mechanical forces play an important role in tissue neovascularization and are a constituent part of modern wound therapies. The mechanisms by which vacuum assisted closure (VAC) modulates wound angiogenesis are still largely unknown. OBJECTIVE:: To investigate how VAC treatment affects wound hypoxia and related profiles of angiogenic factors as well as to identify the anatomical characteristics of the resultant, newly formed vessels. METHODS:: Wound neovascularization was evaluated by morphometric analysis of CD31-stained wound cross-sections as well as by corrosion casting analysis. Wound hypoxia and mRNA expression of HIF-1α and associated angiogenic factors were evaluated by…

3D virtual histopathology of cardiac tissue from Covid-19 patients based on phase-contrast X-ray tomography

eLife 10, e71359 (2021). doi:10.7554/eLife.71359

Comparative Antiproliferative and Antiangiogenic Activity of Cacao Preparations (P06-048-19)

OBJECTIVES: Multiple lines of evidence show the benefits of cacao on inflammation and cardiovascular disease. The relationship between cacao and cancer is less well defined. Cacao contains bioactive compounds with antiangiogenic properties, such as procyanidins and catechins. Angiogenesis, blood vessel formation, is critical for tumor growth and validated target in cancer therapy. We studied the antiangiogenic and anti-tumorigenic potential of two commercially available 100% cacaos (Valrhona and De Zaan). METHODS: L5178y mouse lymphoma cells were incubated with different concentrations of cacao (0, 0.1, 0.3, 1, 3, and 10 µl/ml). The calorimetric methylthiazolyldiphenyl-tetrazolium bromide (…

Functional Adhesion of Pectin Biopolymers to the Lung Visceral Pleura

Pleural injuries and the associated “air leak” are the most common complications after pulmonary surgery. Air leaks are the primary reason for prolonged chest tube use and increased hospital length of stay. Pectin, a plant-derived heteropolysaccharide, has been shown to be an air-tight sealant of pulmonary air leaks. Here, we investigate the morphologic and mechanical properties of pectin adhesion to the visceral pleural surface of the lung. After the application of high-methoxyl citrus pectin films to the murine lung, we used scanning electron microscopy to demonstrate intimate binding to the lung surface. To quantitatively assess pectin adhesion to the pleural surface, we used a custom ad…

Patterns of Carbon-Bound Exogenous Compounds in Patients with Lung Cancer and Association with Disease Pathophysiology.

Abstract Asymptomatic anthracosis is the accumulation of black carbon particles in adult human lungs. It is a common occurrence, but the pathophysiologic significance of anthracosis is debatable. Using in situ high mass resolution matrix-assisted laser desorption/ionization (MALDI) fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometry imaging analysis, we discovered noxious carbon-bound exogenous compounds, such as polycyclic aromatic hydrocarbons (PAH), tobacco-specific nitrosamines, or aromatic amines, in a series of 330 patients with lung cancer in highly variable and unique patterns. The characteristic nature of carbon-bound exogenous compounds had a strong association wi…

Dendritic Cell Migration To The Post Pneumonectomy Lung

Angiogenesis Patterns in Interstitial Lung Disease

Rebalancing β-Amyloid-Induced Decrease of ATP Level by Amorphous Nano/Micro Polyphosphate: Suppression of the Neurotoxic Effect of Amyloid β-Protein Fragment 25-35

Morbus Alzheimer neuropathology is characterized by an impaired energy homeostasis of brain tissue. We present an approach towards a potential therapy of Alzheimer disease based on the high-energy polymer inorganic polyphosphate (polyP), which physiologically occurs both in the extracellular and in the intracellular space. Rat pheochromocytoma (PC) 12 cells, as well as rat primary cortical neurons were exposed to the Alzheimer peptide Aβ25-35. They were incubated in vitro with polyphosphate (polyP); ortho-phosphate was used as a control. The polymer remained as Na+ salt; or complexed in a stoichiometric ratio to Ca2+ (Na-polyP[Ca2+]); or was processed as amorphous Ca-polyP microparticles (C…

Sequence of vascular patterning and gene transcription in the chick chorioallantoic membrane (15.1)

Introduction: The chick chorioallantoic membrane (CAM) is a well-established model of both vasculogenesis and angiogenesis; however, little is known about the genetic control of vascular patterning in the CAM. Methods: Using recent advances in chicken genomics, we investigated the relative expression of 84 angiogenesis genes during the growth and remodeling of the CAM microcirculatory network. Chick embryos, cultured ex ovo, were studied during embryonic development days (EDD) 8-14. UV laser microdissection was used to harvest capillary plexus and 1st, 2nd, and 3rd order conducting vessels for qRT-PCR analysis. Results: Two transcription peaks were observed between EDD 8 and 14. The first p…

Comprehensive three‐dimensional morphology of neoangiogenesis in pulmonary veno‐occlusive disease and pulmonary capillary hemangiomatosis

Abstract Pulmonary veno‐occlusive disease (PVOD) is a rare lung disease characterized by fibrotic narrowing of pulmonary veins leading to pulmonary hypertension (PH) and finally to death by right heart failure. PVOD is often accompanied by pulmonary capillary hemangiomatosis (PCH), a marked abnormal proliferation of pulmonary capillaries. Both morphological patterns often occur together and are thought to be distinct manifestations of the same disease process and accordingly are classified together in group 1′ of the Nice classification of PH. The underlying mechanisms of these aberrant remodeling processes remain poorly understood. In this study, we investigated the three‐dimensional struc…

Water-Dependent Blending of Pectin Films: The Mechanics of Conjoined Biopolymers

Biodegradable pectin polymers have been recommended for a variety of biomedical applications, ranging from the delivery of oral drugs to the repair of injured visceral organs. A promising approach to regulate pectin biostability is the blending of pectin films. To investigate the development of conjoined films, we examined the physical properties of high-methoxyl pectin polymer-polymer (homopolymer) interactions at the adhesive interface. Pectin polymers were tested in glass phase (10&ndash

Biomaterial-Assisted Anastomotic Healing: Serosal Adhesion of Pectin Films

Anastomotic leakage is a frequent complication of intestinal surgery and a major source of surgical morbidity. The timing of anastomotic failures suggests that leaks are the result of inadequate mechanical support during the vulnerable phase of wound healing. To identify a biomaterial with physical and mechanical properties appropriate for assisted anastomotic healing, we studied the adhesive properties of the plant-derived structural heteropolysaccharide called pectin. Specifically, we examined high methoxyl citrus pectin films at water contents between 17–24% for their adhesivity to ex vivo porcine small bowel serosa. In assays of tensile adhesion strength, pectin demonstrated significant…

Early kinetics of integration of collagen-glycosaminoglycan regenerative scaffolds in a diabetic mouse model.

Collagen-glycosaminoglycan scaffolds, originally designed to treat severe burns, are now commonly used in patients with complex wounds associated with diabetes mellitus. In this study, the authors investigated how the thickness of the scaffold would affect cellular integration with the diabetic host and whether this can be accelerated using subatmospheric pressure wound therapy devices.Collagen-glycosaminoglycan scaffolds, 500 to 2000-μm thick, were applied to dorsal wounds in genetically diabetic mice. In addition, 1000-μm collagen-glycosaminoglycan scaffolds with and without silicone were treated with a subatmospheric pressure device (-125 mmHg). On days 5 and 10, cellular and vascular in…

Biologization of Allogeneic Bone Grafts with Polyphosphate: A Route to a Biomimetic Periosteum

Abstract 2935: Novel combination of repurposed drugs induces complete cell invasion arrest of glioblastoma in vitro

Abstract Introduction: Glioblastoma multiforme (GBM) is an aggressive and lethal cancer with a poor prognosis even after conventional treatment (surgery, radiation, chemotherapy). Temozolomide (TMZ) is a standard cyotoxic agent used, despite resistance leading to recurrence. Therefore, additional strategies for targeting the tumor environment are needed. We demonstrate a combination of approved drugs (CAD) repurposed to target GBM leads to complete arrest of GBM cell invasion. Each drug in the combination individually targets diverse tumor pathways: 1) invasion via MMP2 (doxycycline); 2) angiogenesis, inflammation, and proliferation via p53-dependent G1 cell-cycle arrest (celecoxib); 3) aut…

Post‐pneumonectomy Lung Deformation is Associated with Alveolar Type II Cell Apoptosis and Altered Parenchymal Mechanics

Mesopolysaccharides: The extracellular surface layer of visceral organs

The mesothelium is a dynamic and specialized tissue layer that covers the somatic cavities (pleural, peritoneal, and pericardial) as well as the surface of the visceral organs such as the lung, heart, liver, bowel and tunica vaginalis testis. The potential therapeutic manipulation of visceral organs has been complicated by the carbohydrate surface layer—here, called the mesopolysaccharide (MPS)—that coats the outer layer of the mesothelium. The traditional understanding of MPS structure has relied upon fixation techniques known to degrade carbohydrates. The recent development of carbohydrate-preserving fixation for high resolution imaging techniques has provided an opportunity to re-examine…

Utilization of metabolic energy in treatment of ocular surface disorders: polyphosphate as an energy source for corneal epithelial cell proliferation.

Impaired regeneration of the corneal epithelium, as found in many ocular surface diseases, is a major clinical problem in ophthalmology. We hypothesized that corneal epithelial regeneration can be promoted by the physiological, energy-delivering as well as “morphogenetically active” polymer, inorganic polyphosphate (polyP). Corneal limbal explants (diameter, 4 mm) were cultivated on collagen-coated well plates in the absence or presence of polyP (chain length, ∼40 Pi units; 50 μg ml−1) or human platelet lysate (hp-lysate; 5% v/v). Cell outgrowth and differentiation were analyzed after staining with DRAQ5 (nuclei) and rhodamine phalloidin (cytoskeleton), as well as by environmental scanning …

A Novel Biomimetic Approach to Repair Enamel Cracks/Carious Damages and to Reseal Dentinal Tubules by Amorphous Polyphosphate.

Based on natural principles, we developed a novel toothpaste, containing morphogenetically active amorphous calcium polyphosphate (polyP) microparticles which are enriched with retinyl acetate (“a-polyP/RA-MP”). The spherical microparticles (average size, 550 ± 120 nm), prepared by co-precipitating soluble Na-polyP with calcium chloride and supplemented with retinyl acetate, were incorporated into a base toothpaste at a final concentration of 1% or 10%. The “a-polyP/RA-MP” ingredient significantly enhanced the stimulatory effect of the toothpaste on the growth of human mesenchymal stem cells (MSC). This increase was paralleled by an upregulation of the MSC marker genes for osteoblast differ…

Architectural changes of the extracellular matrix in compensatory lung growth (540.2)

Compensatory growth of the remaining lung after murine pneumonectomy (PNX) involves the structural remodeling of the peripheral acini. Although the role of stem cells and local cellular proliferati...

Pectin biopolymer mechanics and microstructure associated with polysaccharide phase transitions.

Polysaccharide polymers like pectin can demonstrate striking and reversible changes in their physical properties depending upon relatively small changes in water content. Recent interest in using pectin polysaccharides as mesothelial sealants suggests that water content, rather than nonphysiologic changes in temperature, may be a practical approach to optimize the physical properties of the pectin biopolymers. Here, we used humidified environments to manipulate the water content of dispersed solution of pectins with a high degree of methyl esterification (high-methoxyl pectin; HMP). The gel phase transition was identified by a nonlinear increase in compression resistance at a water content …

Transformation of Amorphous Polyphosphate Nanoparticles into Coacervate Complexes: An Approach for the Encapsulation of Mesenchymal Stem Cells.

Inorganic polyphosphate [polyP] has proven to be a promising physiological biopolymer for potential use in regenerative medicine because of its morphogenetic activity and function as an extracellular energy-donating system. Amorphous Ca2+ -polyP nanoparticles [Ca-polyP-NPs] are characterized by a high zeta potential with -34 mV (at pH 7.4). This should contribute to the stability of suspensions of the spherical nanoparticles (radius 94 nm), but make them less biocompatible. The zeta potential decreases to near zero after exposure of the Ca-polyP-NPs to protein/peptide-containing serum or medium plus serum. Electron microscopy analysis reveals that the particles rapidly change into a coacerv…

Collagen-inducing biologization of prosthetic material for hernia repair: Polypropylene meshes coated with polyP/collagen

Prostethic mesh material such as nonabsorbable polypropylene used in open and laparoscopic hernia repair are characterized by controllable mechanical properties but may elicit undesirable physiological reactions due to the nonphysiological inert polymer material. We succeeded in developing a biocompatible coating for these meshes, based on a physiological inorganic polymer, polyphosphate (polyP) that is morphogenetically active and used as a metabolic energy source, and a collagen matrix. The polyP/collagen hydrogel material was prepared by a freeze-extraction method, with amorphous Ca-polyP microparticles. Electron microscopy (SEM and REM) studies revealed that the polyP/collagen coats are…

Regulation Of Post-Pneumonectomy Angiogenesis By Type II Pneumocytes

Remodeling of alveolar septa after murine pneumonectomy

In most mammals, removing one lung (pneumonectomy) results in the compensatory growth of the remaining lung. In mice, stereological observations have demonstrated an increase in the number of mature alveoli; however, anatomic evidence of the early phases of alveolar growth has remained elusive. To identify changes in the lung microstructure associated with neoalveolarization, we used tissue histology, electron microscopy, and synchrotron imaging to examine the configuration of the alveolar duct after murine pneumonectomy. Systematic histological examination of the cardiac lobe demonstrated no change in the relative frequency of dihedral angle components (Ends, Bends, and Junctions) ( P &gt…

Pulmonary microvascular architecture in hereditary haemorrhagic telangiectasia

A 24-year-old Caucasian man was admitted with a known hereditary haemorrhagic telangiectasia (HHT) and heterozygous mutation of factor V Leiden following episodes of cerebral infarctions in occipital lobes, cerebellum and brainstem. In his case history, the patient underwent several interventional embolisation of arteriovenous (AV) malformations in the middle and lower lobes (figure 1). However, those were not completely successful as the malformations were diffuse. We performed video-assisted thoracoscopic surgery with a resection of the middle lobe and a wedge resection of segment 10. Figure 1 CT scans depict the pulmonary arteriovenous malformations after re-embolisation in the middle lo…

In vitro and in vivo characterization of porcine acellular dermal matrix for gingival augmentation procedures

Recently, porcine acellular dermal matrix (PADM) has been proposed as a possible alternative to autogenous grafts in periodontal plastic surgery. The aim of the present study was to investigate the in vitro responses of four different oral cell lines cultured on a novel PADM. Furthermore, tissue reaction to PADM was evaluated histologically after subcutaneous implantation in mice.Human gingival fibroblasts (HGF), human osteoblast-like cells, human umbilical vein endothelial cells and human oral keratinocytes (HOK) were cultured and transferred on to the PADM. A tissue culture polystyrene surface served as the control. The viability of all tested cell lines on PADM was measured by using the …

Amorphous, Smart, and Bioinspired Polyphosphate Nano/Microparticles: A Biomaterial for Regeneration and Repair of Osteo-Articular Impairments In-Situ

Using femur explants from mice as an in vitro model, we investigated the effect of the physiological polymer, inorganic polyphosphate (polyP), on differentiation of the cells of the bone marrow in their natural microenvironment into the osteogenic and chondrogenic lineages. In the form of amorphous Ca-polyP nano/microparticles, polyP retains its function to act as both an intra- and extracellular metabolic fuel and a stimulus eliciting morphogenetic signals. The method for synthesis of the nano/microparticles with the polyanionic polyP also allowed the fabrication of hybrid particles with the bisphosphonate zoledronic acid, a drug used in therapy of bone metastases in cancer patients. The r…

Visualization of SARS-CoV-2 in the Lung.

Influence of Different Rehydration Protocols on Biomechanical Properties of Allogeneic Cortical Bone Plates: A Combined in-vitro/in-vivo Study

Introduction: Allogeneic cortical bone plates (CP) are used for alveolar ridge augmentation. Since CP are freeze-dried and dehydrated during processing, the breaking strength (BS) and the flexibility (FX) are reduced, resulting in a relevant risk for plate fractures during insertion. The aim of this study was to evaluate the influence of rehydration time on the biomechanical properties (BS & FX) of CP in-vitro and in vivo.Material and Methods: 40 CP were randomly divided into four experimental groups. (A) untreated control (n = 10), rehydration for 10 (B), 30 (C) and 60 (D) minutes in 0.9% saline solution (n = 10 each). BS [Newton, N] and FX [mm] (force till fracture and distance of deflect…

Three-dimensional scanning electron microscopy of maxillofacial biomaterials

Self-Healing Properties of Bioinspired Amorphous CaCO3/Polyphosphate-Supplemented Cement

There is a strong interest in cement additives that are able to prevent or mitigate the adverse effects of cracks in concrete that cause corrosion of the reinforcement. Inorganic polyphosphate (polyP), a natural polymer that is synthesized by bacteria, even those on cement/concrete, can increase the resistance of concrete to progressive damage from micro-cracking. Here we use a novel bioinspired strategy based on polyP-stabilized amorphous calcium carbonate (ACC) to give this material self-healing properties. Portland cement was supplemented with ACC nanoparticles which were stabilized with 10% (w/w) Na&ndash

Stretch-induced Intussuceptive and Sprouting Angiogenesis in the Chick Chorioallantoic Membrane

Vascular systems grow and remodel in response to not only metabolic needs, but also mechanical influences as well. Here, we investigated the influence of tissue-level mechanical forces on the patterning and structure of the chick chorioallantoic membrane (CAM) microcirculation. A dipole stretch field was applied to the CAM using custom computer-controlled servomotors. The topography of the stretch field was mapped using finite element models. After 3 days of stretch, Sholl analysis of the CAM demonstrated a 7-fold increase in conducting vessel intersections within the stretch field (p 0.05). In contrast, corrosion casting and SEM of the stretch field capillary meshwork demonstrated intense …

Unfused Liver Segments: a Case Report of an Unknown Phenotype of the Conradi-Hünermann-Happle Syndrome

Background: Since its description in 1957, Couinaud`s classification of the segmental organization of the liver has remained valid. However, recent investigations by 3-dimensional computed tomography suggest a significant variability of the vascular anatomy and segment volume. Here, we report a surprise finding during the laparoscopic cholecystectomy of a patient with Conradi-Hünermann-Happle syndrome, in whom the liver segments were not fused.&#x0D; Case report: Laparoscopic cholecystectomy was performed because of recurrent biliary pancreatitis in a 47 year-old male patient, who had been diagnosed with Conradi-Hünermann-Happle syndrome. Upon direct view, the liver parenchyma appeared norm…

3D printing of hybrid biomaterials for bone tissue engineering: Calcium-polyphosphate microparticles encapsulated by polycaprolactone.

Abstract Here we describe the formulation of a morphogenetically active bio-ink consisting of amorphous microparticles (MP) prepared from Ca 2+ and the physiological inorganic polymer, polyphosphate (polyP). Those MP had been fortified by mixing with poly-e-caprolactone (PCL) to allow 3D-bioprinting. The resulting granular PCL/Ca-polyP-MP hybrid material, liquefied by short-time heating to 100 °C, was used for the 3D-printing of tissue-like scaffolds formed by strands with a thickness of 400 µm and a stacked architecture leaving ≈0.5 mm 2 -sized open holes enabling cell migration. The printed composite scaffold turned out to combine suitable biomechanical properties (Young’s modulus of 1.60…

Artificial cartilage bio-matrix formed of hyaluronic acid and Mg2+-polyphosphate.

Here we show that inorganic polyphosphate (polyP), a polyanionic metabolic regulator consisting of multiple phosphate residues linked by energy-rich phosphoanhydride bonds, is present in the synovial fluid. In a biomimetic approach, to enhance cartilage synthesis and regeneration, we prepared amorphous polyP microparticles with Mg2+ as counterions. The particles were characterised by X-ray diffraction (XRD), energy-dispersive X-ray (EDX) and Fourier transformed infrared spectroscopic (FTIR) analyses. Similar particles were obtained after addition of Mg2+ ions to a solution containing hyaluronic acid, as a major component of the synovial fluid, and soluble Na-polyP. The viscous paste-like ma…

Interalveolar pores increase in aging and severe airway obstruction

Molecular Imaging in the Regenerating Post Pneumonectomy Lung

Offene Reparation der inzisionalen Flankenhernie mit retromuskulärer präperitonealer Netzimplantation – Beschreibung der Technik und Ergebnisse einer prospektiven Kohortenstudie

Zusammenfassung Hintergrund Die Operation der Flankenhernie ist wenig standardisiert. Das Hauptproblem der Hernienreparation bei intermuskulärer Netzlage liegt in der Flächenbegrenzung nach dorsal wie auch in der problematischen Fixation des Netzes am Rippenbogen bzw. Beckenkamm. Diese Problematik drückt sich auch aus in der Vielfalt vorgeschlagener Operationsverfahren. Patienten/Material und Methoden Von August 2015 bis Oktober 2016 wurden 9 Patienten wegen einer Narbenhernie der Flanke mit einer retroperitonealen, präperitonealen, offenen Netzreparation operativ versorgt und analysiert. Bei intermuskulärer Netzlage würde das einzubringende Netz umso kleiner ausfallen, je kleiner der kosto…

Microvascular placental alterations in maternal COVID-19

Pulmonary vascular endothelialitis, thrombosis, and angiogenesis in Covid-19

Abstract: BackgroundProgressive respiratory failure is the primary cause of death in the coronavirus disease 2019 (Covid-19) pandemic. Despite widespread interest in the pathophysiology of the disease, relatively little is known about the associated morphologic and molecular changes in the peripheral lung of patients who die from Covid-19. MethodsWe examined 7 lungs obtained during autopsy from patients who died from Covid-19 and compared them with 7 lungs obtained during autopsy from patients who died from acute respiratory distress syndrome (ARDS) secondary to influenza A(H1N1) infection and 10 age-matched, uninfected control lungs. The lungs were studied with the use of seven-color immun…

Deformation-induced transitional myofibroblasts contribute to compensatory lung growth

In many mammals, including humans, removal of one lung (pneumonectomy) results in the compensatory growth of the remaining lung. Compensatory growth involves not only an increase in lung size, but also an increase in the number of alveoli in the peripheral lung; however, the process of compensatory neoalveolarization remains poorly understood. Here, we show that the expression of α-smooth muscle actin (SMA)—a cytoplasmic protein characteristic of myofibroblasts—is induced in the pleura following pneumonectomy. SMA induction appears to be dependent on pleural deformation (stretch) as induction is prevented by plombage or phrenic nerve transection (P < 0.001). Within 3 days of pneumonectomy, …

Free-Floating Mesothelial Cells in Pleural Fluid After Lung Surgery

Objectives: The mesothelium, the surface layer of the heart, lung, bowel, liver and tunica vaginalis, is a complex tissue implicated in organ-specific diseases and regenerative biology; however, the mechanism of mesothelial repair after surgical injury is unknown. Previous observations indicated seeding of denuded mesothelium by free-floating mesothelial cells may contribute to mesothelial healing. In this study, we investigated the prevalence of mesothelial cells in pleural fluid during the 7 days following pulmonary surgery. Study design: Flow cytometry was employed to study pleural fluid of 45 patients after lung resection or transplantation. We used histologically validated mesothelial …

Extracellular Assembly of the Elastin Cable Line Element in the Developing Lung

In the normal lung, a dominant structural element is an elastic "line element" that originates in the central bronchi and inserts into the distal airspaces. Despite its structural importance, the process that leads to development of the cable line element is unknown. To investigate the morphologic events contributing to its development, we used optical clearing methods to examine the postnatal rat lung. An unexpected finding was numerous spheres, with a median diameter of 1-2 µm, within the primary septa of the rat lung. The spheres demonstrated green autofluorescence, selective fluorescent eosin staining, reactivity with carboxyfluorescein succinimidyl ester, and specific labeling with ant…

Restoration of Impaired Metabolic Energy Balance (ATP Pool) and Tube Formation Potential of Endothelial Cells under “high glucose”, Diabetic Conditions by the Bioinorganic Polymer Polyphosphate

Micro-vascularization is a fast, energy-dependent process that is compromised by elevated glucose concentrations such as in diabetes mellitus disease. Here, we studied the effect of the physiological bioinorganic polymer, polyphosphate (polyP), on the reduced ATP content and impaired function of endothelial cells cultivated under "high glucose" (35 mM diabetes mellitus conditions) concentrations. This high-energy biopolymer has been shown to provide a source of metabolic energy, stored in its phosphoanhydride bonds. We show that exposure of human umbilical vein endothelial cells (HUVEC cells) to "high glucose" levels results in reduced cell viability, increased apoptotic cell death, and a d…

Ceylon cinnamon and its major compound Cinnamaldehyde can limit overshooting inflammatory signaling and angiogenesis in vitro: implications for COVID-19 treatment

AbstractOvershooting immune reactions can occur during inflammatory responses that accompany severe infections, such as COVID-19. Cytokines, damage-associated molecular patterns (DAMPs), and reactive oxygen and nitrogen species can generate positive feedback loops of inflammation, leading to long-term complications such as vascular endothelialitis, thrombosis, endothelial dysfunction, neurological impairments, and chronic fatigue. Dexamethasone can limit inflammation by inhibiting the activation of pro-inflammatory transcription factors. High dose dexamethasone, however, has undesirable side effects. Here, we show that Ceylon cinnamon and its major compound cinnamaldehyde can mitigate infla…

A physiologically active interpenetrating collagen network that supports growth and migration of epidermal keratinocytes: zinc-polyP nanoparticles integrated into compressed collagen.

The distinguished property of the physiological polymer, inorganic polyphosphate (polyP), is to act as a bio-intelligent material which releases stimulus-dependent metabolic energy to accelerate wound healing. This characteristic is based on the bio-imitating feature of polyP to be converted, upon exposure to peptide-containing body fluids, from stable amorphous nanoparticles to a physiologically active and energy-delivering coacervate phase. This property of polyP has been utilized to fabricate a wound mat consisting of compressed collagen supplemented with amorphous polyP particles, formed from the inorganic polyanion with an over-stoichiometric ratio of zinc ions. The proliferation and t…

Structural contribution of intravascular blood distension to lung mechanics

Scaffolding Effect of Vascular Distension on Peripheral Lung Mechanics

Analysis of pectin biopolymer phase states using acoustic emissions.

Acoustic emissions are stress or elastic waves produced by a material under external load. Since acoustic emissions are generated from within and transmitted through the substance, the acoustic signature provides insights into the physical and mechanical properties of the material. In this report, we used a constant velocity probe with force and acoustic emission monitoring to investigate the properties of glass phase and gel phase pectin films. In the gel phase films, a constant velocity uniaxial load produced periodic premonitory acoustic emissions with coincident force variations (saw-tooth pattern). SEM images of the gel phase microarchitecture indicated the presence of slip planes. In …

Structural and functional evidence for the scaffolding effect of alveolar blood vessels

A contribution of pulmonary blood distension to alveolar opening was first proposed more than 100 years ago. To investigate the contribution of blood distension to lung mechanics, we studied control mice (normal perfusion), mice after exsanguination (absent perfusion) and mice after varying degrees of parenchymal resection (supra-normal perfusion). On inflation, mean tracheal pressures were higher in the bloodless mouse (4.0α2.5 cmH2O); however, there was minimal difference between conditions on deflation (0.7α0.9 cmH2O). To separate the peripheral and central mechanical effects of blood volume, multi-frequency lung impedance data was fitted to the constant-phase model. The presence or abse…

Mechanical Evidence Of Microstructural Remodeling During Post-Pneumonectomy Compensatory Lung Growth

Transformation of Construction Cement to a Self-Healing Hybrid Binder

A new biomimetic strategy to im prove the self-healing properties of Portland cement is presented that is based on the application of the biogenic inorganic polymer polyphosphate (polyP), which is used as a cement admixture. The data show that synthetic linear polyp, with an average chain length of 40, as well as natural long-chain polyP isolated from soil bacteria, has the ability to support self-healing of this construction material. Furthermore, polyP, used as a water-soluble Na-salt, is subject to Na+/Ca2+ exchange by the Ca2+ from the cement, resulting in the formation of a water-rich coacervate when added to the cement surface, especially to the surface of bacteria-containing cement/c…

Amorphous Polyphosphate and Ca‐Carbonate Nanoparticles Improve the Self‐Healing Properties of both Technical and Medical Cements

Cement is used both as a construction material and for medical applications. Previously, it has been shown that the physiological polymer inorganic polyphosphate (polyP) is morphogenetically active in regeneration of skin, bone, and cartilage. The present study investigates the question if this polymer is also a suitable additive to improve the self-healing capacity not only of construction cement but also of inorganic bone void fillers. For the application in the cement, two different polyP-based amorphous nanoparticles (NP) are prepared, amorphous Ca-polyP NP and amorphous Ca-carbonate (ACC) NP. The particles are integrated into poly(methyl methacrylate) in a concentration ratio of 1:10. …

Aged Mice Devoid of the M3 Muscarinic Acetylcholine Receptor Develop Mild Dry Eye Disease

The parasympathetic nervous system is critically involved in the regulation of tear secretion by activating muscarinic acetylcholine receptors. Hence, various animal models targeting parasympathetic signaling have been developed to induce dry eye disease (DED). However, the muscarinic receptor subtype (M1–M5) mediating tear secretion remains to be determined. This study was conducted to test the hypothesis that the M3 receptor subtype regulates tear secretion and to evaluate the ocular surface phenotype of mice with targeted disruption of the M3 receptor (M3R−/−). The experimental techniques included quantification of tear production, fluorescein staining of the ocular surface, environmenta…

Restoration of cerebral and systemic microvascular architecture in APP/PS1 transgenic mice following treatment with Liraglutide™.

OBJECTIVE: Cerebral microvascular impairments occurring in AD may reduce Aβ peptide clearance and impact upon circulatory ultrastructure and function. We hypothesized that microvascular pathologies occur in organs responsible for systemic Aβ peptide clearance in a model of AD and that Liraglutide (Victoza(®)) improves vessel architecture. METHODS: Seven-month-old APP/PS1 and age-matched wild-type mice received once-daily intraperitoneal injections of either Liraglutide or saline (n = 4 per group) for eight weeks. Casts of cerebral, splenic, hepatic, and renal microanatomy were analyzed using SEM. RESULTS: Casts from wild-type mice showed regularly spaced microvasculature with smooth lumenal…

3D virtual Histopathology of Cardiac Tissue from Covid-19 Patients based on Phase-Contrast X-ray Tomography

X-ray phase-contrast tomography datasets of formalin fixed paraffin embedded unstained cardiac tissue from Covid-19 patients as well as from control tissue. For each group one overview scan of the entire biopsy (3.5mm cross section) from binning and stitching different tomograms (PB bin2, voxel size: 1.3&micro;m) as well as the respective laboratory data (LJ, voxel size: 2&micro;m, tissue masked) and a cone-beam zoom tomogram recorded with waveguide illumination (WG, voxel size: 159 nm) is uploaded. Further datasets can be provided on request. The data has been recorded at the institute for X-ray physics (G&ouml;ttingen, Germany) and DESY at the GINIX instrument, beamline P10 of the PETRAII…