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1.
Front Public Health ; 12: 1442560, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39267636

RESUMEN

Introduction: The importance of improving older adults' mental health is increasing worldwide with the rapid development of the aging process. Green space is an important part of the urban built environment, demonstrates a deep connection with the mental health of older adults, and its internal mechanisms have been widely studied. This study analyzed the influence of urban green spaces on the mental health of older adults via three factors: relative deprivation, physical activity, and social trust. Methods: Based on the 2018 China Labor Dynamics Survey, a multi-level structural equation model was used to explore the mediating roles of relative deprivation, physical activity, social trust in urban green spaces, and the mental health of older adults. Results: Urban green space was positively correlated with the mental health of older adults. Relative deprivation and physical activities played a mediating role between urban green space and the mental health of older adults. Discussion: An increase in urban green spaces can help increase the number of older adults obtaining green space resources, and help them maintain good mental health. Secondly, older adults with a relatively homogeneous environment have more equal opportunities to obtain urban green space resources, which helps to reduce the comparison of older adults in access to green space resources and reduce the adverse impact of relative deprivation on their mental health. Additionally, increasing urban green spaces can encourage older adults to engage in physical activities and improve their mental health. Finally, we suggest improving the accessibility, fairness, and quality of green spaces, paying attention to the psychological needs of older adults, encouraging older adults to engage in physical activities in green spaces, and taking various measures to enhance the positive role of green space on the mental health of older adults.


Asunto(s)
Ejercicio Físico , Salud Mental , Confianza , Humanos , Salud Mental/estadística & datos numéricos , Masculino , Anciano , Femenino , Ejercicio Físico/psicología , China , Persona de Mediana Edad , Confianza/psicología , Encuestas y Cuestionarios , Entorno Construido/estadística & datos numéricos , Parques Recreativos/estadística & datos numéricos , Población Urbana/estadística & datos numéricos
3.
BMC Nephrol ; 25(1): 204, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38907217

RESUMEN

BACKGROUND: The concomitant occurrence of membranous nephropathy and anti-glomerular basement (anti-GBM) disease has been previously described but is extremely rare. However, delayed recognition or misdiagnosis leads to delayed treatment, resulting in worse renal and patient outcomes. CASE PRESENTATION: We present 3 patients with rapidly progressive glomerulonephritis (RPGN), anti-GBM and serum-positive M-type phospholipase A2 receptor (anti-PLA2R) antibody. Renal biopsies revealed PLA2R-associated membranous nephropathy with anti-GBM glomerulonephritis. We analyzed the clinical and pathological characteristics and discussed that the correct diagnosis of membranous nephropathy with anti-GBM should rely on a combination of renal biopsy findings and serological testing. Despite aggressive treatment, one patient received maintenance hemodialysis, one patient progressed to CKD 3 stage, and the other patient died of cerebral infarction. CONCLUSION: The simultaneous occurrence of membranous nephropathy and anti-GBM disease is extremely rare. The correct diagnosis of membranous nephropathy with anti-GBM relies on a combination of renal biopsy findings and serological testing. Early diagnosis is needed to improve the renal dysfunction.


Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular , Glomerulonefritis Membranosa , Receptores de Fosfolipasa A2 , Humanos , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/complicaciones , Glomerulonefritis Membranosa/patología , Glomerulonefritis Membranosa/inmunología , Masculino , Femenino , Persona de Mediana Edad , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/diagnóstico , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/complicaciones , Enfermedad por Anticuerpos Antimembrana Basal Glomerular/terapia , Receptores de Fosfolipasa A2/inmunología , Adulto , Autoanticuerpos/sangre , Biopsia , Glomerulonefritis/diagnóstico , Glomerulonefritis/complicaciones
4.
ACS Appl Mater Interfaces ; 14(49): 54769-54780, 2022 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-36469043

RESUMEN

Exploiting an effective strategy to tailor the construction, composition, and local electronic structure of the photocatalyst surface is pivotal to photocatalytic activity, but remains challenging. Transition metal elements can boost the oxygen evolution reaction activity especially one like Ni in high oxidation states, whereas it is uneasy to prepare Ni3+ under mild conditions or play to their strengths in acidic conditions. In this article, we report a facile "etch and dope" synthesis of Ni3+-doped WO3 nanosheets with oxygen vacancies. Through detailed experimental and theoretical studies, it is established that the abundant oxygen vacancies and the doped Ni3+ ions in the near-surface amorphous layer can synergistically optimize the surface electronic structure of WO3 and the adsorption and desorption of intermediates. Impressively, the etched WO3 nanosheets coupled with Ni3+ offer a greatly promoted photocatalytic performance of 1.78 mmol g-1 h-1, and the photoanode achieves a photocurrent density of 2.11 mA cm-2 at 1.23 V versus reversible hydrogen electrode (VRHE). This work provides a new inspiration for rational manufacture of defects and high-valence metal ions in catalysts for photocatalytic and photoelectrochemical reactions.

5.
Lab Med ; 53(3): 307-313, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-34878509

RESUMEN

OBJECTIVE: To evaluate the effect of sodium dodecyl sulfate (SDS) and 2-mercaptoethanol (2-ME) on antigen-antibody binding when incubated at 100°C, which is the pretreatment temperature required for western blots. METHODS: Serum that tested positive for hepatitis B surface antigen (HBsAg) plus loading buffer were mixed at a ratio of 4:1 and incubated in a water bath. We then detected HBsAg using double immunodiffusion and ELISA. RESULTS: The HBsAg titer was 1:512 in the control group when incubated at 37°C. Incubation with SDS at 100°C reduced the antigen titer to 1:32. The inhibitory effect on HBsAg titer reached 96.9% after incubation at 100°C with SDS and 2-ME. CONCLUSION: We detected strong inhibition of antigens in western blots via SDS and 2-ME. It is likely that false-negative results will be obtained from western blots of antigens with weak resistance to these reagents.


Asunto(s)
Anticuerpos , Antígenos de Superficie de la Hepatitis B , Ensayo de Inmunoadsorción Enzimática , Humanos , Mercaptoetanol/farmacología , Dodecil Sulfato de Sodio/farmacología
6.
J Colloid Interface Sci ; 601: 177-185, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34082227

RESUMEN

Heterogeneously structured materials with supported precious metals, such as Pd, Pt, and Ru, as co-catalysts are important catalysts for efficient photocatalytic water splitting. However, the high costs and low reserves of precious metals have been an obstacle to their application in hydrogen production. In this work, the noble-metal-free Cd0.3Zn0.7S solid solution was designed and synthesized with an optimized molar ratio of Cd/Zn for the best visible light photocatalytic performance. In addition, a heterojunction hybrid material formed between the Cd0.3Zn0.7S and Ni(OH)2 nanosheet was engineered to improve the utilization of light and to inhibit the recombination of holes and electrons. Ni(OH)2 nanosheets assisted the transfer of the photoexcited electrons to participate in the reduction reactions which is critical for efficient and rapid catalytic hydrogen production. The photoelectrochemical property of the hybrid material was investigated with UV-vis absorption, photoluminance (PL) and electrochemical impedance spectroscopy measurements. The mechanism of the high-efficiency and low-cost photocatalytic hydrogen production was established by analyzing the hydrogen evolution kinetics. With the success of replacing precious metal with nickel-based surface heterostructure, this work is expected to provide a new type of photocatalyst for the application of photocatalytic hydrogen production.

7.
Life Sci ; 258: 118146, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32721462

RESUMEN

OBJECTIVE: To investigate protective efficacies and mechanisms of dencichine on diabetic kidney injury via in vitro and in vivo assays. METHODS: Effects of dencichine on hydrogen peroxide (H2O2) induced oxidative damage in HK-2 renal cells were assessed by CCK-8 method. Forty streptozotocin (STZ)-induced diabetic rats with kidney injury were randomly divided into negative control group, three doses of dencichine (40, 80 and 160 mg/kg) groups. Blood biochemical and kidney related indexes as well adrenal morphological changes, apoptosis and autophagy related markers of diabetic rats were measured. RESULTS: Cell viability of HK-2 cells with oxidative damage induced by H2O2 was significantly improved by dencichine with 160 µg/mL for 43.7% and 320 µg/mL for 52.9% compared with control. Moreover, the decreased reactive oxygen species (ROS), and increased intracellular antioxidant enzymes including GPX1, SOD2 and GSH were showed in dencichine groups. In addition, incubation of dencichine in HK-2 cells promoted the increase of p-AMPK, BCL2, LC3, decreased activation of p-mTOR, BAX and Caspase 3. Chronic treatment of dencichine improved the STZ-induced diabetic characteristics of model rats. Further histopathological examination of renal tissues revealed 12-week treatment of dencichine effectively improved the morphology of nephropathy in diabetic rats. Moreover, dencichine also ameliorated excessive oxidation stress, down-regulated renal cell apoptosis and fibrosis related proteins, thereby protected renal tissues in diabetic rats. CONCLUSION: Dencichine ameliorated STZ-induced kidney injury mainly through inhibiting oxidative stress, reducing renal fibrosis, increasing autophagy, and reducing the renal cell apoptosis related proteins to protect nephrocytes and decrease renal tissue damage.


Asunto(s)
Aminoácidos Diaminos/uso terapéutico , Antioxidantes/uso terapéutico , Diabetes Mellitus Experimental/complicaciones , Nefropatías Diabéticas/tratamiento farmacológico , Riñón/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/metabolismo , Nefropatías Diabéticas/patología , Fibrosis , Humanos , Riñón/metabolismo , Riñón/patología , Masculino , Ratas , Ratas Sprague-Dawley
8.
Clin Lab ; 65(9)2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31532113

RESUMEN

BACKGROUND: We investigated the impact of immunohistochemistry (IHC) pre-treatment steps on antigens. METHODS: Salmonella typhimurium was selected as the observed antigen. The antigen was subjected to IHC pre-treatment steps involving a series of reagents, including 10% formaldehyde, ethanol, and xylene. Antigenicity was then measured by agglutination reaction. RESULTS: The agglutination titer for S. typhimurium was higher in the untreated control group than in the experimental group, indicating that pre-treatment inhibited antigen activity. The inhibitory effect of ethanol was greater than that of 10% formaldehyde and xylene. Unexpectedly, partial antigen recovery can be achieved from a preparation of paraffin section after hydration. CONCLUSIONS: S. Antigens may be strongly inhibited (inhibition: 70.8%) by IHC pre-treatment steps, especially by alcohol treatment. There is an experimental foundation for antigen retrieval in IHC.


Asunto(s)
Antígenos/inmunología , Etanol/química , Formaldehído/química , Inmunohistoquímica/métodos , Xilenos/química , Aglutinación/inmunología , Antígenos/química , Humanos , Inmunohistoquímica/normas , Reproducibilidad de los Resultados , Salmonella typhimurium/inmunología , Coloración y Etiquetado/métodos , Coloración y Etiquetado/normas
9.
Dalton Trans ; 47(8): 2602-2609, 2018 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-29388648

RESUMEN

BiVO4-based composites have been extensively investigated as promising photocatalysts due to their strong visible-light absorption. In this work, novel Bi/BiVO4 composites with excellent photocatalytic performance were firstly fabricated via a simple hydrothermal method, using BiVO4 as a self-sacrificing template and N2H4·H2O as a reductant. In the hydrothermal process, partial BiVO4 was reduced to form metallic Bi nanoparticles, which were deposited on the surface of BiVO4. The Bi content in the Bi/BiVO4 composites could be easily tuned by controlling the concentration of the N2H4·H2O solution. The photocatalytic performance of the Bi/BiVO4 composites was examined by studying the photodecomposition of RhB under visible-light illumination. The experimental results revealed that the Bi/BiVO4 composites exhibit high visible-light photocatalytic activity for the photodegradation of RhB compared with that of pure BiVO4. This enhanced photocatalytic activity likely originates from the strong visible-light absorption and high separation efficiency of photogenerated electron-hole pairs by Bi nanoparticles. This work presents a new approach for the development of Bi/BiVO4 composite photocatalysts with high activity and stability.

10.
Gynecol Endocrinol ; 25(7): 464-71, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19903045

RESUMEN

In this study, we examined the long-term influence of a high-fat (HF) diet compared with a standard chow (SC) diet on glucose metabolism in genetically normal Sprague-Dawley rats. As the diet was given for a period of 14 months it represents almost a life-long exposure of the rats to the diet. Results showed that (1) after exposure to 14 months of SC or HF feeding, the fasting glucose levels were below 5.1 mmol/l in both genders; (2) the 2 h plasma glucose concentration (2 h PG) of male rats after an intraperitoneal glucose tolerance test for the SC groups and for the HF groups was significantly higher than for females; (3) the liver triglycerides content was significantly enhanced by HF feeding as compared with SC-feeding, and histological staining showed that both genders of the HF group developed severe liver steatosis; (4) the fasting insulin concentration in blood of HF-fed males was significantly higher than that of females and homeostasis model assessment of insulin resistance was also significantly higher; (5) the insulin secretion capabilities in response to glucose stimulation were significantly higher in HF-fed female rats than that of males. Taken together, these data indicate that glucose intolerance produced by a HF diet in rats shows a gender difference, and females are protected against development of impaired glucose tolerance under HF condition.


Asunto(s)
Alimentación Animal , Grasas de la Dieta/farmacología , Intolerancia a la Glucosa/dietoterapia , Intolerancia a la Glucosa/prevención & control , Adaptación Biológica , Animales , Glucemia/metabolismo , Peso Corporal/fisiología , Ácidos Grasos no Esterificados/sangre , Hígado Graso/dietoterapia , Hígado Graso/prevención & control , Femenino , Homeostasis/fisiología , Insulina/sangre , Insulina/metabolismo , Resistencia a la Insulina/fisiología , Secreción de Insulina , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/fisiología , Hígado/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Caracteres Sexuales , Triglicéridos/metabolismo
11.
Clin Anat ; 17(6): 518-21, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15300873

RESUMEN

We found a case in which inferior mesenteric artery and the common hepatic artery arose from the superior mesenteric artery, forming the common hepatomesenteric trunk, during a routine dissection carried out at Iwate Medical University in 2002. This variation is rare, but can be embryonically explained. A change in the positions of the disappearance of the ventral splanchnic arteries and the longitudinal anastomotic channel results in variations in the system of arteries distributed to the digestive organs. In the present case, the longitudinal anastomotic channel between the superior and the inferior mesenteric arteries survived to form the common mesenteric artery, which was joined by the common hepatic artery, forming the common hepatomesenteric trunk.


Asunto(s)
Arteria Hepática/anomalías , Arteria Mesentérica Inferior/anomalías , Arteria Mesentérica Superior/anomalías , Anciano , Cadáver , Arteria Hepática/anatomía & histología , Humanos , Masculino , Arteria Mesentérica Inferior/anatomía & histología , Arteria Mesentérica Superior/anatomía & histología
12.
J Electron Microsc (Tokyo) ; 52(4): 435-40, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-14599107

RESUMEN

The thicknesses of the lamina lucida and the lamina densa of basement membranes in various kinds of tissues, including the epidermis and mucosal epithelium, and basement membranes adjacent to a Schwann cell, perineurial sheath cell, endothelial cell, pericyte, muscle cell and fat cell, were compared on high-powered transmission electron micrographs. Each tissue and cell possessed a basement membrane with thicknesses of the lamina lucida and lamina densa that were specific to the particular tissue or cell. This indicates that the lamina lucida and lamina densa of the basement membrane of a tissue/cell have a particular constitution. New theories on the molecular constitution between the cell surface and basement membrane may need to be developed.


Asunto(s)
Membrana Basal/ultraestructura , Animales , Células Endoteliales/ultraestructura , Epidermis/ultraestructura , Epitelio/ultraestructura , Masculino , Microscopía Electrónica , Especificidad de Órganos , Ratas , Ratas Wistar
13.
Anat Sci Int ; 78(3): 185-8, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14527134

RESUMEN

We recognized an abnormal anterior belly of the digastric muscle in an 83-year-old male cadaver. Three muscle bundles were observed on the left anterior belly: (i) attached to the left digastric fossa; (ii) attached to the right digastric fossa; and (ii) attached to the raphe of the mylohyoid muscle. Four muscle bundles were recognized on the right anterior belly: (i) attached to raphe of the mylohyoid muscle; (ii, iii) attached to the exterior surface on the base of the mandible from the raphe of the mylohyoid muscle; and (iv) attached to the interior surface on the base of the mandible from the raphe of the mylohyoid muscle. The raphe of the mylohyoid muscle was curved significantly to right and the four abnormal bundles found on the right anterior belly (see above) were attached to its curved point.


Asunto(s)
Músculos Masticadores/anomalías , Músculos Masticadores/patología , Anomalías Maxilofaciales/clasificación , Anomalías Maxilofaciales/patología , Anciano , Anciano de 80 o más Años , Tipificación del Cuerpo , Humanos , Hueso Hioides/anomalías , Hueso Hioides/patología , Masculino , Mandíbula/anomalías , Mandíbula/patología , Nervio Mandibular/anatomía & histología , Nervio Mandibular/patología , Músculos Masticadores/inervación , Valores de Referencia
14.
Med Electron Microsc ; 36(3): 132-8, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14505056

RESUMEN

Scanning electron microscopic (SEM) studies of the interstitial surface of the lamina densa can be performed with dithiothreitol separation, which is the only method of exposing this surface. SEM observation revealed the three-dimensional structures of the meshwork in the lamina densa and anchoring fibrils in dithiothreitol-separated specimens. Detection of the components of the basement membrane can be performed by immunoscanning electron microscopy on this exposed surface by comparing the backscattered and the secondary electron images. SEM observation also revealed the fine structure of the lamina fibroreticularis using separated dermis or the lamina propria mucosae.


Asunto(s)
Membrana Basal/ultraestructura , Ditiotreitol , Epitelio/ultraestructura , Microscopía Electrónica de Rastreo/métodos , Animales , Epidermis/ultraestructura , Humanos , Inmunohistoquímica , Mucosa Bucal/ultraestructura , Ratas , Lengua/ultraestructura
15.
Arch Oral Biol ; 48(3): 237-48, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12648562

RESUMEN

Aperiodic fibrils (AF) project from the interstitial side of the lamina densa of the basement membrane (BM) of the inner enamel epithelium (IE), and show remarkable changes in their morphology during development. The three-dimensional morphology of aperiodic fibrils during development has not been observed, because of the difficulty of exposing the interstitial surface of the BM of the inner enamel epithelium. In the present study, the dithiothreitol separation method was applied to expose the interstitial side of the inner enamel epithelial BM of rat tooth germs for the purpose of observing the exposed aperiodic fibrils by transmission and scanning electron microscopy (TEM and SEM, respectively). After dithiothreitol treatment, the enamel organ (EO) was mechanically separated from the dental papilla (DP). In the region with poorly-developed aperiodic fibrils, the separation occurred at the junction between the inner enamel epithelial BM and the dental papilla, and the aperiodic fibrils were exposed, showing the typical picture of dithiothreitol separation. SEM observation of this region revealed that the aperiodic fibrils were connected to each other and they formed networks. These networks resembled those formed by the anchoring fibrils of epidermal and mucosal epithelial BMs. TEM and SEM observations revealed that there were sidechain-like structures on the surface of the aperiodic fibrils. In the region with well-developed aperiodic fibrils, dithiothreitol treatment was not entirely effective, and some mesenchymal tissues remained on the BM. In this region, TEM observation revealed that the aperiodic fibrils were arranged in parallel with each other, and were connected by the sidechains. Several thin collagen fibrils, which were thought to be immature collagen fibrils (CF) of the predentine, were also connected to the aperiodic fibrils with these sidechains and arranged in parallel with them. Based on SEM and TEM observations, the aperiodic fibrils may be regarded as a kind of anchoring fibrils and they may play a role in connecting the BM with the mesenchymal tissue below. They are also thought to guide the arrangement of collagen fibrils in the surface layer of the predentin.


Asunto(s)
Germen Dentario/ultraestructura , Animales , Membrana Basal/ultraestructura , Esmalte Dental/ultraestructura , Papila Dental/ultraestructura , Ditiotreitol , Órgano del Esmalte/ultraestructura , Epitelio/ultraestructura , Mesodermo/ultraestructura , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Ratas , Ratas Wistar , Manejo de Especímenes/métodos
16.
J Morphol ; 255(2): 244-52, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12474269

RESUMEN

The development of the basement membrane and collagen fibrils below placodes, including the corneal region of the ectoderm, lens epithelium, nasal plate, and auditory vesicle in anuran larvae was observed by transmission electron microscopy and compared with that in nonplacodal regions such as the epidermis, neural tube, and optic vesicle. In the corneal region the lamina densa becomes thick concomitantly with the development of the connecting apparatuses such as hemidesmosomes and anchoring fibrils. The collagen fibrils increase in number and form a multilayered structure, showing similar morphology to the connective tissues below the epidermis. These two areas, i.e., the corneal region and epidermis, possess much collagenous connective tissue below them. On the other hand, the neural tube and ophthalmic vesicle that originated from the neural tube each have a thin lamina densa and a small number of underlying collagen fibrils. The lamina densa does not thicken and the number of collagen fibrils do not significantly increase during development. These two areas possess little extracellular matrix. The nasal plate and auditory vesicle show intermediate characteristics between the epidermis-type and the neural tube-type areas. In these areas, the lamina densa becomes thick and hemidesmosomes and anchoring fibrils develop. The number of collagen fibrils increases during development, but does not show an orderly arrangement; rather, they are randomly distributed. It is thought that the difference in the arrangement of collagen fibrils in different tissues is due to differences in the extracellular matrix around the collagen fibrils. Placodal epithelia have the same origin as epidermis, but during development their morphological characteristics differ and they are not associated with the pattern of extracellular matrix with characteristics of epidermal and corneal multilayered collagen fibril areas.


Asunto(s)
Membrana Basal/embriología , Colágeno/fisiología , Rana temporaria/embriología , Animales , Membrana Basal/ultraestructura , Córnea/embriología , Córnea/ultraestructura , Oído/embriología , Epidermis/embriología , Epidermis/ultraestructura , Cabeza/embriología , Larva/crecimiento & desarrollo , Cristalino/embriología , Cristalino/ultraestructura , Microscopía Electrónica , Sistema Nervioso/embriología , Sistema Nervioso/ultraestructura , Nariz/embriología , Nariz/ultraestructura
17.
J Electron Microsc (Tokyo) ; 51(5): 341-5, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12455919

RESUMEN

Collagen fibrils run in parallel in the endoneurial space, forming fibre bundles. Spaces are evident between these bundles when examined by transmission electron microscopy (TEM). However, the procedures for TEM include chemical fixation, dehydration and embedding, which may cause morphological changes in the specimens. Ultracryo thin sectioning procedures may avoid the artefacts caused by these procedures. An examination of ultrathin frozen sections revealed that the endoneurial space was completely filled with collagen fibrils, with little space between the fibre bundles. These results suggest that the dehydration and/or embedding procedures cause shrinkage of the specimen, resulting in the appearance of a widened space in the endoneurium. Therefore, the widened space between the bundles of collagen fibrils may be a technical artefact.


Asunto(s)
Colágeno/ultraestructura , Nervios Periféricos/química , Animales , Colágeno/fisiología , Secciones por Congelación , Microscopía Electrónica , Nervios Periféricos/diagnóstico por imagen , Ratas , Manejo de Especímenes , Ultrasonografía
18.
J Electron Microsc (Tokyo) ; 51(3): 195-7, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12113627

RESUMEN

The myelin sheath of peripheral nerves was observed by transmission electron microscopy (TEM) using plastic-embedded sections and ultrathin frozen sections. Repeat distances of myelin sheaths were measured in high-powered electron micrographs. The ultrathin frozen sections showed a longer repeat distance than the plastic-embedded sections. The ultrathin frozen sections were thought to contain fewer artefacts, as they had not been subject to dehydration and embedding. It is known that broken myelin sheaths are often observed under conventional TEM. It is thought that these procedures cause contraction and partial destruction of the myelin sheath.


Asunto(s)
Crioultramicrotomía/métodos , Microscopía Electrónica/métodos , Vaina de Mielina/ultraestructura , Animales , Fibras Nerviosas Mielínicas/ultraestructura , Ratas , Ratas Wistar , Nervio Ciático/ultraestructura
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