Search results for "trabecular"
showing 10 items of 30 documents
Anatomy, immunohistochemistry, and numerical distribution of human splenic microvessels.
2019
Abstract The microvascular architecture of the spleen plays an important role in the immunological function of this organ. The different types of vessels are related to different reticular cells each with their own immunomodulatory functions. The present study describes an immunohistochemical and morphometric analysis of the various types of vessels in 21 human autopsy non-pathological splenic samples. On an area of 785,656.37 μm2 for each sample, we classified and quantified the type and number of vascular structures, each according to their morphology and immunohistochemical profile, and obtained the ratios between them. The distribution of trabecular vessels and the characteristics of th…
A topological look at human trabecular bone tissue
2017
Bone quality is affected by trabecular architecture at microscopic level. Various abnormalities of bone tissue lead to altered strength and to an increased susceptibility to fracture, such as Osteoporosis and Osteoarthritis, two major health burdens of our society. These are two complex musculoskeletal diseases that mainly concern bone tissue. In the last twenty years, there has been a growing interest in finding an appropriate topological model for the micro-architecture of trabecular bone tissue. In particular, we prove that these models involve general topological spaces. The appropriate notion to deal with is that of CW-complex.
Impact of freeze-thaw cytoablation on aqueous outflow patterns in ex vivo anterior chamber perfusion cultures and whole eyes
2022
Background: Porcine eyes have been widely used as ex vivo models in glaucoma research, as they share similar features with human eyes. Freeze-thawing is a non-invasive technique that has been used to obliterate living cells in anterior segment ex vivo cultures, to prepare them for further research such as cellular repopulation. This technique has previously been shown to reduce the intraocular pressure (IOP) in porcine eyes. The aim of this study was to investigate whether freeze-thaw cytoablation causes corresponding canalogram outflow changes in perfused anterior segment cultures (AFT) and whole porcine eyes (WFT). We hypothesized that the known IOP drop in AFT after trabecular meshwork a…
Ventricular tachycardia in non-compaction of left ventricle: Is this a frequent complication?
2007
Background: Isolated left ventricular non-compaction is the result of incomplete myocardial morphogenesis, leading to persistence of the embryonic myocardium. The condition is recognized by an excessively prominent trabecular meshwork and deep intertrabecular recesses of the left ventricle. Whether these intertrabecular recesses are a favorable substrate for ventricular arrhythmias is unclear. Some reports have found that the fatal ventricular arrhythmias may occur in approximately half of the patients. In this report we investigated about this association. Methods and Results: In total we evaluated a continuous series of 238 patients affected by non-compaction. Periodic Holter monitoring w…
Anatomic site evaluation of the palatal bone for temporary orthodontic anchorage devices.
2008
: Objectives: The aim of the present study was to assess the micromorphologic characteristics of the palatal bone from an implantologic standpoint. Materials and Methods: The material consisted of tissue blocks of autopsy material from 22 subjects (18 males, three females) between 18 and 63 years of age. The specimens comprised the anterior median palatal region from 5 to 10 mm behind the incisive foramen. They were prepared in the transversal plane according to ground thin-section technology. The midpalatal area as well as an area of 3 mm bilateral to the midline were assessed, and a classification of quantitative palatal bone availability was developed. Results: The findings could be divi…
Endothelin Antagonism: Effects of FP Receptor Agonists Prostaglandin F2αand Fluprostenol on Trabecular Meshwork Contractility
2006
Purpose This study analyzes additional mechanisms behind the ocular hypotensive effect of prostaglandin F (PGF) receptor (FP receptor) agonists PGF2alpha and fluprostenol (fluprostenol-isopropyl ester [travoprost]), which reduce intraocular pressure (IOP) in patients with glaucoma probably by enhancing uveoscleral flow. The trabecular meshwork (TM) is actively involved in IOP regulation through contractile mechanisms. Contractility of TM is induced by endothelin (ET)-1, a possible pathogenic factor in glaucoma. The involvement of FP receptor agonists in the ET-1 effects on TM function was studied. Methods The effects of FP receptor agonists on contractility of bovine TM (BTM) were investiga…
Early diagnosis of osteoporosis by means of orthopantomograms and oral x-rays: a systematic review.
2011
Osteoporosis is a systemic bone disease that is characterized by a generalized reduction of the bone mass. It is the main cause of fractures in elderly women. Bone densitometry is used in the lumbar spine and hip in order to detect osteoporosis in its early stages. Different studies have observed a correlation between the bone mineral density of the jaw (BMD) and that of the lumbar spine and/or hip. On the other hand, there are studies that evaluate the findings in the orthopantomograms and perapical X-rays, correlating them with the early diagnosis of osteoporosis and highlighting the role of the dentist in the early diagnosis of this disease. Materials and methods: A search was carried ou…
A biphasic calcium phosphate coating for potential drug delivery affects early osseointegration of titanium implants.
2016
Background Calcium phosphate (CaP) surface coatings may accelerate osseointegration and serve as a drug delivery system for mineral-binding biomolecules. In a pilot study, the impact of a commercially available, thin CaP coating on early osseous bone remodeling was compared with a modern, subtractive-treated rough surface (SLA-like) in an animal trial. Methods In 16 rabbits, 32 endosseous implants (CaP; n = 16, SLA-like; n = 16) were bilaterally inserted in the proximal tibia after randomization. After 2 and 4 weeks, bone-implant contact (BIC;%) in the cortical (cBIC) and the trabecular bone (sBIC) as well as volume of bone within the screw thread with the highest amount of new-formed bone …
Association between radiography-based subchondral bone structure and MRI-based cartilage composition in postmenopausal women with mild osteoarthritis
2016
Summary Objective Our aim was to investigate the relation between radiograph-based subchondral bone structure and cartilage composition assessed with delayed gadolinium enhanced magnetic resonance imaging of cartilage (dGEMRIC) and T 2 relaxation time. Design Ninety-three postmenopausal women (Kellgren–Lawrence grade 0: n = 13, 1: n = 26, 2: n = 54) were included. Radiograph-based bone structure was assessed using entropy of the Laplacian-based image ( E Lap ) and local binary patterns ( E LBP ), homogeneity indices of the local angles (HI Angles,mean , HI Angles,Perp , HI Angles,Paral ), and horizontal (FD Hor ) and vertical fractal dimensions (FD Ver ). Mean dGEMRIC index and T 2 relax…
Endothelin receptor B in trabecular meshwork
2007
Abstract Endothelin-1 (ET-1), the most potent vasoconstrictor known to date, seems to be involved in the pathogenesis of primary open angle glaucoma. ET-1 was found in different tissues of the eye and in high concentrations in the aqueous humour. The effects of ET-1 are mediated by two receptors, ET-A receptor (ET-AR) and ET-B receptor (ET-BR), which are both expressed in bovine trabecular meshwork (TM). ET-1 induced contraction of TM predominantly by activation of ET-AR. This study analyzes the role of ET-BR in TM function and investigates the synthesis of ET-1 by human TM (HTM) cells. The effect of IRL-1620, a specific ET-BR agonist, on contractility of bovine TM (BTM) was investigated wi…