Diabetes Mellitus and Its Impact on Patient-Profile and In-Hospital Outcomes in Peripheral Artery Disease

2021

Background: In patients with peripheral artery disease (PAD), the impact of diabetes mellitus (DM) on patient-profile and adverse in-hospital events is not well investigated. Methods: The German nationwide inpatient sample 2005–2019 was used for this analysis. Hospitalized PAD patients were stratified for DM and the influence of DM on patient-profile and adverse in-hospital events was investigated. Results: Our study comprised 2,654,871 hospitalizations (54.3% aged ≥70 years, 36.7% females) of patients with PAD in Germany 2005–2019. Among these, 864,691 (32.6%) patients had DM and 76,716 (2.9%) died during hospitalization. Diabetic PAD patients revealed an aggravated cardiovascular profile …

Intraperitoneal adhesions-an ongoing challenge between biomedical engineering and the life sciences

2011

Peritoneal adhesions remain a relevant clinical problem despite the currently available prophylactic barrier materials. So far, the physical separation of traumatized serosa areas using barriers represents the most important clinical strategy for adhesion prevention. However, the optimal material has not yet been found. Further optimization or pharmacological functionalization of these barriers could give an innovative input for peritoneal adhesion prevention. Therefore, a more complete understanding of pathogenesis is required. On the basis of the pathophysiology of adhesion formation the main barriers currently in clinical practice as well as new innovations are discussed in the present r…

Recurrence of pleomorphic adenoma of the parotid gland-predictive value of cadherin-11 and fascin

2008

The predictive value of cadherin-11, tenascin, fascin, and mucin-1 as markers for the likelihood of recurrence in pleomorphic adenoma of the parotid gland was examined. In this retrospective study we analysed 20 tumours from16 patients by immunohistochemistry. Staining intensities were measured using a semiquantitative scoring approach; localisation (tumour centre vs border) as well as clinical data were analysed and correlated with follow-up. Cadherin-11 was increased in recurrent tumours. However, no changes of fascin, tenascin or mucin-1 were observed. Cadherin-11 and fascin were increased in primary tumours of patients with later recurrence, with fascin upregulation restricted to the tu…

Impact of polymer-modified gold nanoparticles on brain endothelial cells: exclusion of endoplasmic reticulum stress as a potential risk factor

2016

A library of polymer-coated gold nanoparticles (AuNPs) differing in size and surface modifications was examined for uptake and induction of cellular stress responses in the endoplasmic reticulum (ER stress) in human brain endothelial cells (hCMEC/D3). ER stress is known to affect the physiology of endothelial cells (ECs) and may lead to inflammation or apoptosis. Thus, even if applied at non-cytotoxic concentrations ER stress caused by nanoparticles should be prevented to reduce the risk of vascular diseases and negative effects on the integrity of barriers (e.g. blood-brain barrier). We exposed hCMEC/D3 to twelve different AuNPs (three sizes: 18, 35, and 65 nm, each with four surface-modif…

The extent of adhesion induction through electrocoagulation and suturing in an experimental rat study.

2008

Objective To investigate the effect of three types of peritoneal trauma occurring during surgery (high-frequency bipolar current, suturing, and mechanical damage) on postoperative adhesion formation in a rodent animal model. Design Randomized, controlled experimental trial in an in vitro animal model. Setting Laboratory facilities of a university department of obstetrics and gynecology. Animal(s) Thirty-five female Wistar rats. Intervention(s) Bilateral experimental lesions were created on the abdominal wall in every animal. The effect of minimal electrocoagulation was examined by creating lesions (n = 14) through sweeps of a bipolar forceps with a duration of 1 second and standardized pres…

Going beyond histology. Synchrotron micro-computed tomography as a methodology for biological tissue characterization: from tissue morphology to indi…

2009

Current light microscopic methods such as serial sectioning, confocal microscopy or multiphoton microscopy are severely limited in their ability to analyse rather opaque biological structures in three dimensions, while electron optical methods offer either a good three-dimensional topographic visualization (scanning electron microscopy) or high-resolution imaging of very thin samples (transmission electron microscopy). However, sample preparation commonly results in a significant alteration and the destruction of the three-dimensional integrity of the specimen. Depending on the selected photon energy, the interaction between X-rays and biological matter provides semi-transparency of the spe…

High resolution X-ray tomography – three-dimensional characterisation of cell–scaffold constructs for cartilage tissue engineering

2014

AbstractSynchrotron radiation based microcomputed tomography (SR-μCT) has become a valuable tool for the structural analysis of different types of biomaterials. This methodology allows the non-destructive investigation of specimens in their three-dimensional context. In the present paper, articular cartilage is taken as an exemplary tissue to demonstrate the suitability of the SR-μCT method for the investigation of biomaterials for different tissue engineering approaches. Thus, a biodegradable scaffold for cartilage tissue engineering in different modifications was analysed. Using enhanced phase contrast imaging, it was possible to demonstrate single cells without further metal staining. Th…

Semiautomated quantification of the fibrous tissue response to complex three‐dimensional filamentous scaffolds using digital image analysis

2021

Fibrosis represents a relevant response to the implantation of biomaterials, which occurs not only at the tissue-material interface (fibrotic encapsulation) but also within the void fraction of complex three-dimensional (3D) biomaterial constructions (fibrotic ingrowth). Usual evaluation of the biocompatibility mostly depicts fibrosis at the interface of the biomaterial using semiquantitative scores. Here, the relations between encapsulation and infiltrating fibrotic growth are poorly represented. Virtual pathology and digital image analysis provide new strategies to assess fibrosis in a more differentiated way. In this study, we adopted a method previously used to quantify fibrosis in visc…

Glutathione Peroxidase-1 Deficiency Potentiates Dysregulatory Modifications of Endothelial Nitric Oxide Synthase and Vascular Dysfunction in Aging

2014

Recently, we demonstrated that gene ablation of mitochondrial manganese superoxide dismutase and aldehyde dehydrogenase-2 markedly contributed to age-related vascular dysfunction and mitochondrial oxidative stress. The present study has sought to investigate the extent of vascular dysfunction and oxidant formation in glutathione peroxidase-1–deficient ( GPx-1 −/− ) mice during the aging process with special emphasis on dysregulation (uncoupling) of the endothelial NO synthase. GPx-1 −/− mice on a C57 black 6 (C57BL/6) background at 2, 6, and 12 months of age were used. Vascular function was significantly impaired in 12-month-old GPx-1 −/− -mice as compared with age-matched controls. Oxidan…

Boron determination in liver tissue by combining quantitative neutron capture radiography (QNCR) and histological analysis for BNCT treatment plannin…

2011

The typical primary malignancies of the liver are hepatocellular carcinoma and cholangiocarcinoma, whereas colorectal liver metastases are the most frequently occurring secondary tumors. In many cases, only palliative treatment is possible. Boron neutron capture therapy (BNCT) represents a technique that potentially destroys tumor tissue selectively by use of externally induced, locally confined secondary particle irradiation. In 2001 and 2003, BNCT was applied to two patients with colorectal liver metastases in Pavia, Italy. To scrutinize the rationale of BNCT, a clinical pilot study on patients with colorectal liver metastases was carried out at the University of Mainz. The distribution o…

Subcellular distribution of choline acetyltransferase by immunogold electron microscopy in non-neuronal cells: Placenta, airways and murine embryonic…

2012

Abstract Aims Acetylcholine is synthesized in more or less all mammalian cells. However, little is known about the subcellular location of acetylcholine synthesis. Therefore, in the present experiments the subcellular location of the synthesizing enzyme choline acetyltransferase (ChAT) was investigated by anti-ChAT immunogold electron microscopy in human placenta and airways as well as in a murine embryonic stem cell line (CGR8 cell line). Main methods Human tissue was obtained as so-called surplus tissue (after delivery/surgical removal because of lung tumor); the CGR8 stem cell line was cultured under standard conditions. For human tissue a monoclonal mouse anti-ChAT antibody (ab) was use…

Tissue engineered pre-vascularized buccal mucosa equivalents utilizing a primary triculture of epithelial cells, endothelial cells and fibroblasts

2015

Artificial generated buccal mucosa equivalents are a promising approach for the reconstruction of urethral defects. Limiting in this approach is a poor blood vessel supply after transplantation, resulting in increased morbidity and necrosis. We generated a pre-vascularized buccal mucosa equivalent in a tri-culture of primary buccal epithelial cells, fibroblasts and microvascular endothelial cells, using a native collagen membrane as a scaffold. A successful pre-vascularization and dense formation of capillary-like structures at superficial areas was demonstrated. The lumen size of pre-formed blood vessels corresponded to the capillary size in vivo (10-30 μm). Comparing native with a highly …

Innovative barriers for peritoneal adhesion prevention: liquid or solid? A rat uterine horn model.

2005

Objective To compare the effects of solid barriers (PDLA membrane and foil, Interceed), innovative barrier solutions (Adept and Hyalobarrier Gel, phospholipid emulsion), and Ringer’s lactate solution in preventing postsurgical peritoneal adhesions in the rat. Design Prospective, randomized experimental study. Setting Rat model in an academic research environment. Animal(s) Female, nonpregnant Wistar rats. Intervention(s) Standardized surgical injuries were applied to the parietal and visceral peritoneum and the uterine horns. The barrier agents were applied and the wound was closed. A second-look laparoscopy was performed 31 days after surgery to assess adhesion formation. Main Outcome Meas…

Betulinic Acid Protects from Ischemia-Reperfusion Injury in the Mouse Retina

2021

Ischemia/reperfusion (I/R) events are involved in the pathophysiology of numerous ocular diseases. The purpose of this study was to test the hypothesis that betulinic acid protects from I/R injury in the mouse retina. Ocular ischemia was induced in mice by increasing intraocular pressure (IOP) to 110 mm Hg for 45 min, while the fellow eye served as a control. One group of mice received betulinic acid (50 mg/kg/day p.o. once daily) and the other group received the vehicle solution only. Eight days after the I/R event, the animals were killed and the retinal wholemounts and optic nerve cross-sections were prepared and stained with cresyl blue or toluidine blue, respectively, to count cells in…

Influence of cell proportions and proliferation rates on FDG uptake in squamous-cell esophageal carcinoma: a PET study.

2008

We investigated the influence of cell proportions and proliferation activities on tumor maximum standard uptake value (SUV(max)) in patients with squamous-cell esophageal cancer (SCEC).Sixteen (16) patients with untreated SCEC were examined with (18)F-flourodeoxyglucose positron emission tomography (FDG-PET). The tumor SUV(max) were calculated. Tumors were resected by transthoracic esophagectomy. Tissues were stained with hematoxylin and eosin for the measurement of cell proportions and MIB-1 for measurement of proliferation indices (PIs). Tumor SUV and histologic data were related by using multiple linear regression analysis.The mean proportion of tumor cells in the tumor site was 58.1% (+…

New perspectives on the renal slit diaphragm protein podocin.

2011

Podocin is a critical component of the glomerular filtration barrier, its mutations causing recessive steroid-resistant nephrotic syndrome. A GenBank analysis of the human podocin (NPHS2) gene resulted in the possible existence of a new splice variant of podocin in the kidney, missing the in-frame of exon 5, encoding the prohibitin homology domain. Using RT–polymerase chain reaction and immunoblotting followed by sequence analysis, we are for the first time able to prove the expression of a novel podocin isoform (isoform 2), exclusively and constitutively expressed in human podocytes. Furthermore, we reveal singular extrarenal podocin expression in human and murine testis. Our data show the…

CpG-DNA loaded multifunctional MnO nanoshuttles for TLR9-specific cellular cargo delivery, selective immune-activation and MRI

2012

Initiation of pathways that lead to a proliferation and chemoresistance by Toll-like receptors (TLRs) are an important factor in cancer progression. Multifunctional magnetic nanoparticles equipped with a pathogen-derived ligand (CpG) functioning as TLR agonists were used to show the impact of immune activation on human HNSCC (head and neck squamous cell carcinoma) cells. The response of human cancer cells to TLR signaling is linked to tumor biology. The magnetic MnO nanoparticles were coated with a multifunctional polymer, displaying no cytotoxicity and being able to enter cells while carrying foreign DNA (unmethylated CpG) to recognize intracellular TLR9. Both the particle and the nucleic …

Signalling molecules and growth factors for tissue engineering of cartilage-what can we learn from the growth plate?

2009

Modern tissue engineering concepts integrate cells, scaffolds, signalling molecules and growth factors. For the purposes of regenerative medicine, fetal development is of great interest because it is widely accepted that regeneration recapitulates in part developmental processes. In tissue engineering of cartilage the growth plate of the long bone represents an interesting, well-organized developmental structure with a spatial distribution of chondrocytes in different proliferation and differentiation stages, embedded in a scaffold of extracellular matrix components. The proliferation and differentiation of these chondrocytes is regulated by various hormonal and paracrine factors. Thus, mem…

Activation of mitogen-activated protein kinase extracellular signal-related kinase in head and neck squamous cell carcinomas after irradiation as par…

2010

Background. Irradiation plays a pivotal role in head and neck squamous cell carcinoma (HNSCC) treatment. However, especially recurrent tumors frequently show increased radioresistance. We analyzed irradiation-stimulated mitogen-activated protein kinase (MAPK) signaling pathways to define cellular rescue mechanisms. Methods. Irradiated HNSCC cells were screened for MAPK activation and results were confirmed and refined by functional analyses. Extracellular signal-regulated kinase (ERK) inhibitor U0126 application enabled us to specify postradiogenic cellu- lar responses. Vascular endothelial growth factor (VEGF) levels were analyzed additionally. Results. We observed a pronounced and time-de…

Biological responses to individualized small titanium implants for the treatment of focal full-thickness knee cartilage defects in a sheep model.

2019

Abstract Background The present study aimed to evaluate the functional, radiological and histological outcome of a customized focal implant for the treatment of focal full-thickness cartilage defects in sheep. Methods The study used magnetic resonance imaging data as the basis for construction of the titanium implant using a three-dimensional printing technique. This was then placed on the medial condyle of the knee joint in eight sheep and left in place in vivo over a period of six months. Following euthanasia, the local biological response was analyzed using micro-computed tomography, light microscopy and histological evaluation (International Cartilage Repair Society (ICRS) score). The v…

Flotillin-involved uptake of silica nanoparticles and responses of an alveolar-capillary barrier in vitro

2013

AbstractDrug and gene delivery via nanoparticles across biological barriers such as the alveolar-capillary barrier of the lung constitutes an interesting and increasingly relevant field in nanomedicine. Nevertheless, potential hazardous effects of nanoparticles (NPs) as well as their cellular and systemic fate should be thoroughly examined. Hence, this study was designed to evaluate the effects of amorphous silica NPs (Sicastar) and (poly)organosiloxane NPs (AmOrSil) on the viability and the inflammatory response as well as on the cellular uptake mechanisms and fate in cells of the alveolar barrier. For this purpose, the alveolar epithelial cell line (NCI H441) and microvascular endothelial…

A pilot study of laparoscopic adhesion prophylaxis after myomectomy with a copolymer designed for endoscopic application.

2009

Abstract Study Objective To assess the laparoscopic handling and safety of D,L-polylactide-e-caprolactone-trimethylene carbonate (PCT) copolymer after myomectomy and compare it with icodextrin. In contrast to previously developed solid barriers, the material has rationally designed properties that are advantageous for convenient laparoscopic application. Design A randomized, single-blinded clinical study (Canadian Task Force Classification I). Setting Single-center study in a German University Hospital. Patients Thirty patients who underwent laparoscopic myomectomy were enrolled. Interventions After laparoscopic myomectomy and subsequent reconstruction of the uterus with interrupted sutures…

Role of α1-adrenoceptor subtypes on corneal epithelial thickness and cell proliferation in mice

2018

Adrenergic stimuli are important for corneal epithelial structure and healing. The purpose of the present study was to examine the hypothesis that the lack of a single α1-adrenoceptor (α1-AR) subtype affects corneal epithelial thickness and cell proliferation. Expression levels of α1-AR mRNA were determined in mouse cornea using real-time PCR. In mice devoid of one of the three α1-AR subtypes (α1A-AR−/−, α1B-AR−/−, α1D-AR−/−) and in wild-type controls, thickness of individual corneal layers, the number of epithelial cell layers, and average epithelial cell size were determined in cryosections. Endothelial cell density and morphology were calculated in corneal explants, and epithelial cell p…

Adhesion prophylaxis using a copolymer with rationally designed material properties.

2008

Physical barriers are the only licensed adjuncts for adhesion prophylaxis in the United States and Europe. Here, we investigate D,L-polylactide-epsilon-caprolactonetrimethylenecarbonate (PCT copolymer), which is a rationally designed biomaterial, as an adhesion barrier.PCT copolymer membranes were produced by polymerization of the monomers, dissolution in organic solvents, and subsequently processing them by means of modified phase inversion and freeze drying. In vitro cytotoxicity was assayed by fibroblast culture. In vivo adhesion prophylaxis was studied in a rat model that involved standardized traumatization by electrocautery and suturing. The quantity and quality of the resulting adhes…

Differential expression of cell adhesion molecules in inflamed appendix: correlation with clinical stage.

1998

The diagnosis of ‘early inflamed’, ‘recurrent’ or ‘sub-acute’ appendicitis is often difficult and accompanied by controversies between clinical data, histological findings, and their interpretation. The expression of the intercellular cell adhesion molecule-1 (ICAM-1), the vascular cell adhesion molecule-1 (VCAM-1), and E-selectin has been studied in 61 appendicectomy specimens for possible use as a diagnostic tool. This study demonstrates a different expression of CAM by endothelial (EC) and mesothelial cells (MC) in the various stages of appendicitis, with early E-selectin and ICAM-1 expression in EC, followed by VCAM-1 in EC and MC. Appendices from patients with prolonged clinical sympto…

Immobilization and controlled release of prostaglandin E2 from poly-L-lactide-co-glycolide microspheres.

2009

Prostaglandin E(2) (PGE(2)) is an arachidonic acid metabolite involved in physiological homeostasis and numerous pathophysiological conditions. Furthermore, it has been demonstrated that prostaglandins have a stimulating effect not only on angiogenesis in situ and in vitro but also on chondrocyte proliferation in vitro. Thus, PGE(2) represents an interesting signaling molecule for various tissue engineering strategies. However, under physiological conditions, PGE(2) has a half-life time of only 10 min, which limits its use in biomedical applications. In the present study, we investigated if the incorporation of PGE(2) into biodegradable poly-L-lactide-co-glycolide microspheres results in a …

Analysis of differentially expressed proteins in oral squamous cell carcinoma by MALDI-TOF MS

2010

J Oral Pathol Med (2010) 40: 369–379 Purpose:  To explore the presence of differentially expressed proteins in OSCC for discrimination of tumour and normal mucosa to establish potential biomarkers and therapeutic targets. Experimental Design:  Paired protein samples of 12 individuals (tongue cancer and non-cancerous mucosa) were separated by two-dimensional polyacrylamid gel electrophoresis. The protein patterns were compared pairwise and protein spots were quantified. We identified about 70 regulated proteins which we subsequently identified by MALDI-TOF mass spectrometry. Results:  Cancerous and non-cancerous tissues could be most precisely distinguished by a panel of proteins. They inclu…

Poly(γ-Glutamic Acid) as an Exogenous Promoter of Chondrogenic Differentiation of Human Mesenchymal Stem/Stromal Cells

2015

Cartilage damage and/or aging effects can cause constant pain, which limits the patient's quality of life. Although different strategies have been proposed to enhance the limited regenerative capacity of cartilage tissue, the full production of native and functional cartilaginous extracellular matrix (ECM) has not yet been achieved. Poly(γ-glutamic acid) (γ-PGA), a naturally occurring polyamino acid, biodegradable into glutamate residues, has been explored for tissue regeneration. In this work, γ-PGA's ability to support the production of cartilaginous ECM by human bone marrow mesenchymal stem/stromal cells (MSCs) and nasal chondrocytes (NCs) was investigated. MSC and NC pellets were cultur…

The fungal lactone oxacyclododecindione is a potential new therapeutic substance in the treatment of lupus-associated kidney disease.

2013

Recently oxacyclododecindione (Oxa), a macrocyclic lactone isolated from the imperfect fungus Exserohilum rostratum, has been described as a potent transcription inhibitor of inducible proinflammatory and profibrotic genes in cell culture models. As kidney disease in systemic lupus erythematosus is characterized by aberrant expression of inflammatory mediators and infiltration of immune cells, we investigated the effect of Oxa in MRL-Fas(lpr) mice, a model of systemic lupus erythematosus. These mice develop a spontaneous T-cell and macrophage-dependent autoimmune disease including severe glomerulonephritis that shares features with human lupus. Comparable to the results of in vitro models, …

Tissue response to five commercially available peritoneal adhesion barriers-A systematic histological evaluation

2017

Separating wounded serosa by physical barriers is the only clinically approved adjunct for postoperative adhesion prevention. Since the optimal adhesion barrier has not been found, it is essential to improve our pathogenic understanding of adhesion formation and to compare the effects of different barrier materials on tissue and cells. Wistar rats underwent standardized peritoneal damage and were treated either with Seprafilm, Adept, Intercoat, Spraygel, SupraSeal or remained untreated as a control. 14 days postoperatively, the lesions were explanted and histomorphologically analyzed using the European ISO score to evaluate material implants. Striking differences between the material groups…

Biological tolerance of different materials in bulk and nanoparticulate form in a rat model: sarcoma development by nanoparticles

2006

In order to study the pathobiological impact of the nanometre-scale of materials, we evaluated the effects of five different materials as nanoparticulate biomaterials in comparison with bulk samples in contact with living tissues. Five groups out of 10 rats were implanted bilaterally for up to 12 months with materials of the same type, namely TiO 2 , SiO 2 , Ni, Co and polyvinyl chloride (PVC), subcutaneously with bulk material on one side of the vertebral column and intramuscularly with nanoparticulate material on the contralateral side. At the end of each implantation time, the site was macroscopically examined, followed by histological processing according to standard techniques. Malign…

Increased radioresistance via G12S K-Ras by compensatory upregulation of MAPK and PI3K pathways in epithelial cancer

2011

Background Irradiation-induced signaling via the 2 pathways, Raf-MEK-ERK and PI3K-Akt, is known to be closely associated with a limited response to radiotherapy. In the present study we analyzed the relevance of constitutively active K-Ras for postradiogenic pathway stimulation and the option of coordinated inhibition to overcome these rescue mechanisms. Methods We used 2 epithelial tumor cell lines as a model system, one of them harboring a G12S K-Ras mutation. Cells were irradiated and the effect of combined treatment with ionizing radiation and inhibitors on the expression of pERK and pAkt was determined by Western blotting. Additionally, clonogenic assays were performed to functionally …

LATE-BREAKING ABSTRACT: Comparative studies on bronchuswall-thickness by histologic and computed tomographic measurements of porcine lungs

2015

Aims: Histologic slides are commonly used as template in the evaluation and development of medical imaging methods.Diseases like Asthma and COPD show characteristic changes in airway morphology and airway measurement by computed tomography is a promising diagnostic approach.However,shrinkage caused by fixation and histological processing is known in lung tissue.In this study,the thickness of bronchus walls in paraffin and frozen sections as well as in CT and MicroCT were compared. Methods: Airway measurements of swine lungs were performed after freezing in ventilated condition in liquid nitrogen by measuring the wall thickness of 7 bronchi via CT and MicroCT as well as in frozen and paraffi…

Giant bronchogenic cyst within the aortic wall mimicking symptoms of acute type A aortic dissection.

2010

Fascin upregulation in primary head and neck squamous cell carcinoma is associated with lymphatic metastasis

2014

Fascin is an actin-bundling protein that is associated with cellular motility and cancer-cell invasion. The present study aimed to examine the expression of fascin in head and neck squamous cell carcinoma (HNSCC) and its potential use as a biomarker. In a prospective study with a median follow-up time of 48.8 months, tumor tissues, adjacent healthy tissues and cervical lymph node metastases were collected from 25 patients and analyzed by immunohistochemistry. The specimens were scored according to the intensity of fascin staining and the percentage of tumor cells stained using a semi-quantitative scoring approach; the data were analyzed and correlated with clinical follow-up observations. A…

Molecular interactions between human cartilaginous endplates and nucleus pulposus cells: a preliminary investigation.

2014

Study Design. Conditioned media (CM) of cartilaginous endplates (CEPs) of intervertebral discs were analyzed in a bioassay with regard to their influence on matrix turnover and inflammatory factors on nucleus pulposus (NP) cells of the same patient. CEP tissue underwent further histological and ultrastructural analysis. Objective. To identify possible interactions between the CEP and the disc via molecular factors that may influence disc matrix degradation and to determine degenerative changes of CEP tissue. Summary of Background Data. Impaired endplate perme-ability due to degeneration and calcification is considered to be a key contributor to disc degeneration. An upregulation of metallop…

Remodeling of peritoneal-like structures by mesothelial cells: its role in peritoneal healing.

1999

Abstract Background. Intraabdominal adhesions are a common complication following laparotomy. Since the exact mechanisms involved in this processes are unknown we have analyzed in vitro the role of mesothelial cells in peritoneal healing. Material and methods. Human mesothelial cells from omental tissue were cultivated for 2 weeks in a three-dimensional culture either on or in a collagen type I matrix. The effects of blood and collagen matrix were analyzed by exposing mesothelial cells to an overlying blood clot, simulating intraperitoneal bleeding, or a second collagen layer. The production of collagen types III and IV, fibronectin, and laminin was analyzed with immunohistochemical methods…

PECAM-1 expression in human mesothelial cells: an in vitro study.

1996

Mesothelial cells are actively involved in inflammatory processes by expressing a set of cell adhesion molecules (CAMs). Transmigration of leukocytes into inflamed tissues requires a chemotactic stimulus and engagement of platelet-endothelial cell adhesion molecule-1 (PECAM-1). To investigate the kinetics involved in peritonitis, pure cultures of mesothelial cells are necessary. In previous studies, we have found that human mesothelial cells (HOMES) show a weak constitutive expression of PECAM-1, which cannot be further stimulated by cytokines. It is known that all serous cavities and body fluids contain numerous macrophages which strongly express this adhesion molecule. To identify the cel…

Downregulation of alpha-galactosidase A upregulates CD77: functional impact for Fabry nephropathy.

2009

Anderson-Fabry disease, an inherited deficiency in the lysosomal enzyme alpha-galactosidase A, is characterized by the progressive accumulation of globotriaosylceramide (Gb3), also known as CD77. We sought to clarify the pathogenesis of Fabry disease by establishing a cell model of this disorder. The expression of alpha-galactosidase A was transiently silenced by RNA interference in HK2 and primary human renal epithelial cells and stably silenced in HK2 cells by retroviral transfection with small hairpin RNA. All of the silenced cells had histological similarities to cells of patients with Fabry disease. The cells had reduced viability, significant accumulation of intracellular Gb3, and a m…

Genotoxic effects of zinc oxide nanoparticles

2015

The potential toxicity of nanoparticles has currently provoked public and scientific discussions, and attempts to develop generally accepted handling procedures for nanoparticles are under way. The investigation of the impact of nanoparticles on human health is overdue and reliable test systems accounting for the special properties of nanomaterials must be developed. Nanoparticular zinc oxide (ZnO) may be internalised through ambient air or the topical application of cosmetics, only to name a few, with unpredictable health effects. Therefore, we analysed the determinants of ZnO nanoparticle (NP) genotoxicity. ZnO NPs (15-18 nm in diameter) were investigated at concentrations of 0.1, 10 and …

Accuracy of automatic airway morphometry in computed tomography-correlation of radiological-pathological findings.

2010

Abstract Objectives Airway morphology shows characteristic changes in different pathologies. This study assesses the accuracy of a current automatic airway assessment technique by correlating CT images of porcine airways to histological slices of the same localization. Materials and methods Four isolated and ventilated porcine lungs were frozen in a liquid nitrogen bath and examined with a CT scanner (MDCT). This technique both preserved normal radiomorphological appearance and made it possible to slice the specimens for histological examination for subsequent correlation. The parameters wall thickness (WT), wall percentage (WP), and total diameter (TD) were assessed by computer-aided measu…

Influence of organophosphate poisoning on human dendritic cells.

2013

Organophosphourus compounds (OPC, including nerve agents and pesticides) exhibit acute toxicity by inhibition of acetylcholinesterase. Lung affections are frequent complications and a risk factor for death. In addition, epidemiological studies reported immunological alterations after OPC exposure. In our experiments we investigated the effects of organophosphourus pesticides dimethoate and chlorpyrifos on dendritic cells (DC) that are essential for the initial immune response, especially in the pulmonary system. DC, differentiated from the monocyte cell line THP-1 by using various cytokines (IL-4, GM-CSF, TNF-α, Ionomycin), were exposed to organophosphourus compounds at different concentrat…

A Direct Comparison of Seprafilm, Adept, Intercoat, and Spraygel for Adhesion Prophylaxis

2010

Background Commercially available agents for adhesion prophylaxis are legion but there is a lack of direct comparisons between them. Here we compare four of the most commonly used adhesion barriers against a control group in a clinically relevant rat model. Material and Methods Standardized lesions were created in Wistar rats using electrocautery and suturing. Subsequently, the experimental lesions were treated with Seprafilm (n = 30), Adept (n = 30), Intercoat (n = 30), Spraygel (n = 30), or no barrier (n = 30). The resulting adhesions were examined 14 d postoperatively. Results The mean area covered by adhesion was 77% in the control group, 46% in animals treated with Seprafilm, 54% in an…

Intra-operative locally injected pharmacotherapy as a novel strategy for adhesion prophylaxis.

2012

Abstract Background Pharmacotherapy for peritoneal adhesion prophylaxis has been a focus for intensive research. Previous strategies included intravenous and intraperitoneal application of suitable pharmaceutical agents. However, success of these strategies in humans has been limited. Here we describe intra-operative local injection of pharmaceuticals as a novel strategy for adhesion prophylaxis. Methods N  = 208 peritoneal lesions were created in 26 adult Wistar rats. In each animal, lesions on one flank were randomly chosen for treatment with locally injected prednisolone whereas the contralateral side was injected with normal saline. Half of the animals were randomly selected for early a…

Increased basic fibroblast growth factor release and proliferation in xenotransplanted squamous cell carcinoma after combined irradiation/anti-vascul…

2012

Novel strategies of cancer therapy combine irradiation and anti-angiogenic active compounds. However, little is known concerning the undesired cellular and molecular effects caused by this novel treatment concept. We used a mouse squamous cell carcinoma (SCC) xenotransplantation model to evaluate the potential undesired effects which compromise the success of this therapeutic combination. SCCs were subcutanously implanted in nude mice. Animals were treated with a fractionated irradiation scheme (5x4 Gy) alone or in combination with daily injections of anti-vascular endothelial growth factor (VEGF) antibodies. Controls remained untreated. Before and after treatment, resonance imaging (MRI), …

The effect of the pro-inflammatory cytokine tumor necrosis factor-alpha on human joint capsule myofibroblasts.

2009

Introduction Previous studies have shown that the number of myoblastically differentiated fibroblasts known as myofibroblasts (MFs) is significantly increased in stiff joint capsules, indicating their crucial role in the pathogenesis of post-traumatic joint stiffness. Although the mode of MFs' function has been well defined for different diseases associated with tissue fibrosis, the underlying mechanisms of their regulation in the pathogenesis of post-traumatic joint capsule contracture are largely unknown. Methods In this study, we examined the impact of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α) on cellular functions of human joint capsule MFs. MFs were challenged w…

Biological performance of cell-encapsulated methacrylated gellan gum-based hydrogels for nucleus pulposus regeneration

2014

Limitations of current treatments for intervertebral disc (IVD) degeneration have promoted interest in the development of tissue-engineering approaches. Injectable hydrogels loaded with cells can be used as a substitute material for the inner IVD part, the nucleus pulposus (NP), and provide an opportunity for minimally invasive treatment of IVD degeneration. The NP is populated by chondrocyte-like cells; therefore, chondrocytes and mesenchymal stem cells (MSCs), stimulated to differentiate along the chondrogenic lineage, could be used to promote NP regeneration. In this study, the in vitro and in vivo response of human bone marrow-derived MSCs and nasal chondrocytes (NCs) to modified gellan…

Honeybees produce millimolar concentrations of non-neuronal acetylcholine for breeding: possible adverse effects of neonicotinoids

2016

The worldwide use of neonicotinoid pesticides has caused concern on account of their involvement in the decline of bee populations, which are key pollinators in most ecosystems. Here we describe a role of non-neuronal acetylcholine (ACh) for breeding of Apis mellifera carnica and a so far unknown effect of neonicotinoids on non-target insects. Royal jelly or larval food are produced by the hypopharyngeal gland of nursing bees and contain unusually high ACh concentrations (4–8 mM). ACh is extremely well conserved in royal jelly or brood food because of the acidic pH of 4.0. This condition protects ACh from degradation thus ensuring delivery of intact ACh to larvae. Raising the pH to ≥5.5 and…

Tomographic and Topographic Investigation of Poly-D,L-Lactide-Co-Glycolide Microspheres Loaded with Prostaglandine E<sub>2</sub> for Exte…

2010

Polymeric, biodegradable microspheres represent a good reliable system to investigate the release of bioactive substances in both in vitro and in vivo applications. Common biomaterials for the synthesis of these microspheres are aliphatic polyesters of the poly(α-hydroxy)acids, especially poly-L-lactides (PLA) and polyglycolides (PGA) or their copolymers poly-D,L-lactide-co-glycolides (PLGA). In our own previous studies we have developed PLGA microspheres with integrated PGE2 as model substance for a wide range of biomedical applications, especially in angiogenesis, fracture healing and cartilage repair. The synthesis is based on a binary solvent in water emulsion approach, where two differ…

Phenotypic redifferentiation and cell cluster formation of cultured human articular chondrocytes in a three-dimensional oriented gelatin scaffold in …

2013

Modern tissue engineering strategies comprise three elemental parameters: cells, scaffolds and growth factors. Articular cartilage represents a highly specialized tissue which allows frictionless gliding of corresponding articulating surfaces. As the regenerative potential of cartilage is low, tissue engineering-based strategies for cartilage regeneration represent a huge challenge. Prostaglandins function as regulators in cartilage development and metabolism, especially in growth plate chondrocytes. In this study, it was analyzed if prostaglandin E2 (PGE2) has an effect on the phenotypic differentiation of human chondrocytes cultured in a three-dimensional (3D) gelatin-based scaffold made …

PET Lung Ventilation/Perfusion Imaging Using 68Ga Aerosol (Galligas) and 68Ga-Labeled Macroaggregated Albumin

2012

Pulmonary imaging using ventilation/perfusion (V/P) single-photon emission tomography (V/P scan) with Tc-99m-labeled radiotracers is a well-established diagnostic tool for clinically suspected pulmonary embolism (PE). Ga-68 aerosol (Galligas) and Ga-68-labeled macroaggregated albumin (MAA) are potential tracers for positron emission tomography (PET) lung V/P imaging and could display an advantage over conventional V/P scans in terms of sensitivity and specificity. After radiochemical and animal studies, the clinical applicability of Ga-68 aerosol (Galligas) and Ga-68-labeled MAA was investigated in an exploratory study in patients with clinical suspicion of PE. PET scans were acquired using…

Visions for regenerative medicine: interface between scientific fact and science fiction.

2006

This article gives a brief overview of the authors' views on the future development of tissue engineering with respect to the challenges both to the materials and life sciences. Emphasis will be placed on the advantages of three-dimensional bioresorbable polymers in combination with relevant molecular cues and the application of autologous stem or progenitor cells. There is a requirement for much more diversity in the synthesis of so-called "intelligent" materials, which respond to external stimuli, as well as the development of novel drug and gene delivery systems. In addition, much more basic research is necessary in developmental biology and the application of modern cell and molecular b…

Reconstruction of Peritoneal-like Structure in Three-Dimensional Collagen Gel Matrix Culture

1997

The peritoneum is a serous membrane consisting of different kinds of cells and extracellular matrix components (ECM). The aim of the present study was to develop a three-dimensional (3D) in vitro culture system for possible investigation of pathological conditions of the peritoneum. Human omental mesothelial cells (MC) and endothelial cells from the umbilical vein (EC) were cultivated either on (MC) or in (EC) a preformed type I collagen matrix. In 3D culture mesothelial cells showed their phenotypical in vivo characteristics and the synthesis of a new basal membrane (BM). Endothelial cells developed vessel-like structures, produce a BM and express E-selectin after TNF-alpha stimulation. Th…

Engineering a Microvascular Capillary Bed in a Tissue-Like Collagen Construct

2014

Previous studies have shown that plastic compression (PC) of collagen gels allows a rapid and controlled fabrication of matrix- and cell-rich constructs in vitro that closely mimic the structure and characteristics of tissues in vivo. Microvascular endothelial cells, the major cell type making up the blood vessels in the body, were added to the PC collagen to determine whether cells attach, survive, grow, and express endothelial cell characteristics when seeded alone or in coculture with other cells. Endothelial cells seeded on the PC collagen containing human foreskin fibroblasts (HFF) or human osteoblasts (HOS) formed vessel-like structures over 3 weeks in culture without the addition of …

Characterization of oriented protein-ceramic and protein-polymer-composites for cartilage tissue engineering using synchrotron μ-CT

2007

Abstract In this paper we report on the synthesis of three different gelatine based scaffold materials for the reconstruction of articular cartilage defects. The first scaffold design is based on an unmodified, oriented gelatine network, while the second design further comprises an attached inorganic hydroxyapatite layer and the third design includes poly(l-lactide) microspheres as a model material for future drug-release applications. All three scaffold designs were characterized and imaged using synchrotron μ-CT, obtaining a complete volumetric reconstruction of a previously defined sample region. Furthermore, two unmodified scaffolds were cultivated for one week with porcine chondrocytes…

Uptake of poly(2-hydroxypropylmethacrylamide)-coated gold nanoparticles in microvascular endothelial cells and transport across the blood-brain barri…

2020

The facile and modular functionalization of gold nanoparticles makes them versatile tools in nanomedicine, for instance, photothermal therapy, contrast agents or as model nanoparticles to probe drug-delivery mechanisms. Since endothelial cells from various locations in the body exhibit unique phenotypes we quantitatively examined the amount of different sized poly(2-hydroxypropylmethacrylamide)-coated gold nanoparticles internalized into primary human dermal endothelial cells or human brain endothelial cells (hCMEC/D3) by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and visualized the nanoparticles using light and electron microscopy. Poly(2-hydroxypropylmethacrylamide)…

Role of  1-Adrenoceptor Subtypes in Pupil Dilation Studied With Gene-Targeted Mice

2014

PURPOSE The α₁A-adrenoceptor (α₁A-AR) subtype was suggested to mediate contraction and trophic effects in the iris dilator muscle, and thus its pharmacological blockade may be involved in intraoperative floppy iris syndrome. We tested the hypothesis that the α₁A-AR mediates pupil dilation and trophic effects in the mouse iris. METHODS The α₁-AR subtype mRNA expression was quantified in iris tissue by real-time PCR. To assess the role of individual α₁-ARs for mediating pupil dilation, the α₁-AR agonist phenylephrine was topically applied to the ocular surface of mice deficient in one of the three α₁-AR subtypes (α₁A-AR(-/-), α₁B-AR(-/-), α₁D-AR(-/-), respectively) and wild-type controls. Cha…

Interleukin 6 (IL-6) deficiency delays lupus nephritis in MRL-Faslpr mice: the IL-6 pathway as a new therapeutic target in treatment of autoimmune ki…

2009

Objective.To investigate the pathophysiological effect of interleukin 6 (IL-6) on lupus nephritis in MRL-Faslprmice.Methods.We generated IL-6-deficient MRL-Faslprmice using a backcross/intercross breeding scheme. Renal pathology was evaluated using immunohistochemistry detection for macrophages, lymphocytes, vascular cell adhesion molecule-1 (VCAM-1), and TUNEL (terminal deoxynucleotide transferase-mediated dUTP nick end-labeling) for apoptotic cells, and renal IgG and C3 deposition by immunofluorescence staining. Expression of inflammatory markers in the spleen was analyzed by quantitative real-time reverse transcription-polymerase chain reaction. Serum cytokine concentrations were detecte…

Tissue expansion of lung bronchi due to tissue processing for histology – A comparative analysis of paraffin versus frozen sections in a pig model

2019

Tissue shrinking due to fixation and processing is well known. However, the degree of shrinking varies significantly with the tissue type as well as the processing method and is not well studied in various tissues. In daily pathological routine workflow, histological specimens from frozen and paraffin sections are performed from the same tissue. In the present study we compared the thickness of bronchus walls obtained from paraffin and frozen sections.Pig lungs were frozen in ventilated condition in liquid nitrogen and 36 bronchi were isolated after dissection. Frozen sections of 5 μm thickness were performed and the remaining tissue was fixed and embedded in paraffin after fixation in 4% f…

Comparison of histological and computed tomographic measurements of pig lung bronchi.

2020

Aim Light microscopy is used as template in the evaluation and further development of medical imaging methods. Tissue shrinkage caused by histological processing is known to influence lung tissue dimensions. In diagnosis of COPD, computed tomography (CT) is widely used for automated airway measurement. The aim of this study was to compare histological and computed tomographic measurements of pig lung bronchi. Methods Airway measurements of pig lungs were performed after freezing under controlled inflation pressure in a liquid nitrogen bath. The wall thickness of seven bronchi was measured via Micro-CT and CT using the integral-based method (IBM) and the full-width-at-half-maximum method (FW…

2006

Prostaglandin E2 (PGE2) plays an important role in bone development and metabolism. To interfere therapeutically in the PGE2 pathway, however, knowledge about the involved enzymes (cyclooxygenases) and receptors (PGE2 receptors) is essential. We therefore examined the production of PGE2 in cultured growth plate chondrocytes in vitro and the effects of exogenously added PGE2 on cell proliferation. Furthermore, we analysed the expression and spatial distribution of cyclooxygenase (COX)-1 and COX-2 and PGE2 receptor types EP1, EP2, EP3 and EP4 in the growth plate in situ and in vitro. PGE2 synthesis was determined by mass spectrometry, cell proliferation by DNA [3H]-thymidine incorporation, mR…

Implanted neonatal human dermal fibroblasts influence the recruitment of endothelial cells in mice

2012

The vascularization of new tissue within a reasonable time is a crucial prerequisite for the success of different cell- and material-based strategies. Considering that angiogenesis is a multi-step process involving humoral and cellular regulatory components, only in vivo assays provide the adequate information about vessel formation and the recruitment of endothelial cells. The present study aimed to investigate if neonatal human dermal fibroblasts could influence in vivo neovascularization. Results obtained showed that fibroblasts were able to recruit endothelial cells to vascularize the implanted matrix, which was further colonized by murine functional blood vessels after one week. The ve…

Emulsion-based synthesis of PLGA-microspheres for the in vitro expansion of porcine chondrocytes.

2007

Abstract The in vitro cell expansion of autologous chondrocytes is of high interest in regenerative medicine since these cells can be used to treat joint cartilage defects. In order to preserve chondrocyte phenotype, while optimizing adhesion on microspheres, several processing parameters for the microsphere synthesis were varied. In this study three different polylactide-co-glycolides were used with differing lactide–glycolide ratios (85:15 and 50:50) and differing inherent viscosities. An emulsion route was established, where the polymer was dissolved in chloroform and then injected into a stirred polyvinyl alcohol–water solution at different polymer concentrations and different stirring …

Impact of polymer-modified gold nanoparticles on brain endothelial cells: exclusion of endoplasmic reticulum stress as a potential risk factor

2016

A library of polymer-coated gold nanoparticles (AuNPs) differing in size and surface modifications was examined for uptake and induction of cellular stress responses in the endoplasmic reticulum (ER stress) in human brain endothelial cells (hCMEC/D3). ER stress is known to affect the physiology of endothelial cells (ECs) and may lead to inflammation or apoptosis. Thus, even if applied at non-cytotoxic concentrations ER stress caused by nanoparticles should be prevented to reduce the risk of vascular diseases and negative effects on the integrity of barriers (e.g. blood–brain barrier). We exposed hCMEC/D3 to twelve different AuNPs (three sizes: 18, 35, and 65 nm, each with four surface-modif…