Light Microscopic Study (light + microscopic_study)

Distribution by Scientific Domains


Selected Abstracts


T2 relaxation reveals spatial collagen architecture in articular cartilage: A comparative quantitative MRI and polarized light microscopic study

MAGNETIC RESONANCE IN MEDICINE, Issue 3 2001
Miika T. Nieminen
Abstract It has been suggested that orientational changes in the collagen network of articular cartilage account for the depthwise T2 anisotropy of MRI through the magic angle effect. To investigate the relationship between laminar T2 appearance and collagen organization (anisotropy), bovine osteochondral plugs (N = 9) were T2 mapped at 9.4T with cartilage surface normal to the static magnetic field. Collagen fibril arrangement of the same samples was studied with polarized light microscopy, a quantitative technique for probing collagen organization by analyzing its ability to rotate plane polarized light, i.e., birefringence (BF). Depthwise variation of safranin O-stained proteoglycans was monitored with digital densitometry. The spatially varying cartilage T2 followed the architectural arrangement of the collagen fibril network: a linear positive correlation between T2 and the reciprocal of BF was established in each sample, with r = 0.91 ± 0.02 (mean ± SEM, N = 9). The current results reveal the close connection between the laminar T2 structure and the collagen architecture in histologic zones. Magn Reson Med 46:487,493, 2001. © 2001 Wiley-Liss, Inc. [source]


Evaluation by scanning acoustic microscopy (SAM) on glomerular lesion of IgA nephropathy

NEPHROLOGY, Issue 2001
H Kiyomoto
IgA nephropathy (IgAN) is known to commonly cause of end-stage renal failure in Japan. The glomerular lesions of IgAN have histological variations. The determination of prognosis and therapeutic strategy should be carefully done by experts because morphological information from renal biopsies using ordinary optical microscopy is usually qualitative and subjective. Moreover, the histological items for the evaluation of glomerular lesions seems to be unsatisfactory for expression of the disease condition of IgAN. The beneficial properties of scanning acoustic microscopy (SAM) include not only observation of microstructure but also quantitative measurement of acoustic propagation speed (APS), indicating the tissue elasticity. In the present study we compared the APS of glomeruli with the pathological scores that were determined by ordinary light microscopy. We used stocked human renal biopsy specimens diagnosed as IgAN (n = 12) and normal/minimal changes (n = 5). All samples were taken by renal biopsy in Kagawa Medical University Hospital during 1997,2000 under informed consent of the patients. The obtained renal tissue were immersed in 10% formalin and embedded in paraffin. A fixed specimen was consecutively cut into 4 ,m slices. One of the deparaffinized 4 ,m-specimens was directly utilized for SAM without any staining, and the others were stained with haematoxylin-eosin and Masson Trichrome for counting cell number and evaluation of collagen accumulation. For the measurement of glomerular APS, the sample line was set on the equator of the glomerulus and then scanning of the X,Z axis was carried out to obtain the interference fringes that were analysed with a computer imaging software in order to calculate the APS. In light microscopic study, pathological scores were evaluated semiquantitatively by two independent investigators who were unaware of the sample number. Glomerular lesions were scored into five grades and glomerular cell number was also counted in individual glomerulus. The computer-assisted imaging analyser Win ROOF (Mitani, Fukui, Japan) was also used for the determination of glomerular collagen content in specimens stained by Masson Trichrome. A two-dimensional image (C-mode scanning) of SAM enabled imaging of glomerulus in renal biopsy specimen compatible with findings of ordinary light microscopy without staining dye. The glomerular APS in IgAN was significantly higher than in normal/minimal changes. This alteration of glomerular APS in IgAN was positively correlated to both semiquantitative pathological scores and glomerular collagen content determined by light microscopy. However, the cell number of glomelurus did not change between IgAN and normal/minimal change. As a result, we conclude that the glomerular lesion, especially matrix expansion in IgAN, was comparable with the absolute value among specimens. Therefore, it is suggested that SAM method is a novel and useful technique for quantitative evaluation of glomerular lesion in IgAN. [source]


Vertebral artery atherosclerosis: a risk factor in the use of manipulative therapy?

PHYSIOTHERAPY RESEARCH INTERNATIONAL, Issue 3 2002
Jeanette Mitchell BSc (Physiotherapy), MSc Senior Lecturer
Abstract Background and Purpose Vertebrobasilar insufficiency, a direct result of compromised blood flow in the vertebrobasilar circulation, may be caused by stretching and/or compression of the vertebral arteries, particularly if superimposed on underlying atherosclerosis of the vessels. This is an important consideration when using manipulative therapy techniques. The aim of the present study was to investigate the incidence of atherosclerosis and to calculate the relative associated decrease in blood flow in the third and fourth parts of the vertebral artery, in a sample of the adult population. Method A laboratory-based experimental investigation was used to study 362 vertebral arteries from embalmed adult cadavers that were routinely processed for light microscopic study. The incidence of each grade of atherosclerosis in the vessels was recorded. Atherosclerosis was classified as grades 0,5, where Grade 0 represented no atherosclerosis and Grade 5 a fully developed plaque occluding more than 75% of the vessel lumen. From mean measurements of 188 of these arteries, the estimated decrease in luminal cross-sectional area and the relative decrease in blood flow in the atherosclerotic vessels were calculated. Results The highest incidence of atherosclerosis found was Grade 3 (third part of the vertebral artery (VA3): 42.0%; fourth part of the vertebral artery (VA4): 35.2%). An estimated decrease in artery luminal cross-sectional area to 6.2% of normal in Grade 5 atherosclerosis was found. Because blood flow is proportional to the fourth power of the vessel radius, relative decreases in blood flow in grades 1,5 atherosclerosis from 100% to 0% (with critical closing pressure in vessels), respectively, are likely to occur. Conclusions These data suggest that, as significant numbers of the sample showed marked (Grade 3+) atherosclerosis, concomitant with decreased blood flow in the vertebral arteries, this population is at risk for developing vertebrobasilar insufficiency. Because other Western populations may be similarly at risk, particular care should be taken when considering the use of rotational manipulative therapy techniques in treatments of the cervical spine. Copyright © 2002 Whurr Publishers Ltd. [source]


Distribution of olfactory epithelium in the primate nasal cavity: Are microsmia and macrosmia valid morphological concepts?

THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 1 2004
Timothy D. Smith
Abstract The terms "microsmatic" and "macrosmatic" are used to compare species with greater versus lesser olfactory capabilities, such as carnivores compared to certain primates. These categories have been morphologically defined based on the size of olfactory bulb and surface area of olfactory epithelium in the nasal fossa. The present study examines assumptions regarding the morphological relationship of bony elements to the olfactory mucosa, the utility of olfactory epithelial surface area as a comparative measurement, and the utility of the microsmatic concept. We examined the distribution of olfactory neuroepithelium (OE) across the anteroposterior length of the nasal fossa (from the first completely enclosed cross-section of the nasal fossa to the choanae) in the microsmatic marmoset (Callithrix jacchus) compared to four species of nocturnal strepsirrhines (Otolemur crassicaudatus, O. garnetti, Microcebus murinus, and Cheirogaleus medius). Adults of all species were examined and infant C. jacchus, O. crassicaudatus, M. murinus, and C. medius were also examined. All specimens were serially sectioned in the coronal plane and prepared for light microscopic study. Distribution of OE across all the turbinals, nasal septal surfaces, and accessory spaces of the nasal chamber was recorded for each specimen. The right nasal fossae of one adult C. jacchus and one neonatal M. murinus were also three-dimensionally reconstructed using Scion Image software to reveal OE distribution. Findings showed OE to be distributed relatively more anteriorly in adult C. jacchus compared to strepsirrhines. It was also distributed more anteriorly along the nasal septal walls and recesses in neonates than adults. Our findings also showed that OE surface area was not a reliable proxy for receptor neuron numbers due to differing OE thickness among species. Such results indicate that nasal cavity morphology must be carefully reconsidered regarding traditional functional roles (olfaction versus air conditioning) assigned to various nasal cavity structures. At present, the microsmatic concept itself lacks a basis in nasal chamber morphology, since OE may have varying patterns of distribution among different primates. © 2004 Wiley-Liss, Inc. [source]


Effects of ,-Toxin of Staphylococcus aureus on Ciliary Activity of Nasal Epithelial Cells ,

THE LARYNGOSCOPE, Issue 12 2000
Chung Seop Kim MD
Abstract Objectives To investigate the in vitro effects of staphylococcal ,-to-in on ciliary activity and the in vivo effects on sinusitis induction. Study Design The in vitro effects of staphylococcal ,-to-in on ciliary activity were investigated at different concentrations and e-posure times. E-perimental sinusitis was induced in rabbits with application of ,-to-in and confirmed 7 days later. Methods Ciliated epithelial cells were taken from the ma-illary sinus mucosa of 10 rabbits. Five culture dishes from each rabbit were used for the e-perimental group, and one culture dish from each rabbit was used for the control group. In the experimental group, ciliary beat frequency (CBF) was measured at concentrations of 0.1, 1, 2, 5 and 10 U/mL of ,-toxin using a video-computerized analysis technique, while in the control group, culture medium containing no toxin was used. CBF was measured 1, 2, 4, 6, 8, 12, 24, and 48 hours after administration of ,-toxin. To induce experimental sinusitis, 2 U/mL of ,-toxin was percutaneously applied to the maxillary sinus of 10 rabbits without occlusion of the natural ostium, while normal saline was percutaneously applied to the right-side maxillary sinus of 4 rabbits in the control group. At 7 days, mucosal membranes were taken from the inferomedial wall of the maxillary sinus for light microscopic study. Results CBF dropped significantly after an 8-hour incubation at 2, 5, and 10 U/mL of ,-to-in. No ciliary activity was observed after a 24-hour incubation at 2 and 5 U/mL and a 12-hour incubation at 10 U/mL of ,-to-in. Mucoid, purulent discharge was observed in the ma-illary sinuses of the ,-to-in,applied group. Prominent epithelial disruption and infiltration of inflammatory cells into the epithelium and lamina propria were observed in the ,-to-in,applied group. Conclusions Staphylococcal ,-to-in may reduce ciliary activity and induce sinusitis without occlusion of the natural ostium of the ma-illary sinus in rabbits. This study provides another animal model of sinusitis for understanding the pathogenesis of sinusitis induced by bacterial e-oto-ins. [source]