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1.
Glial cells have a major role in protecting neurons against various forms of stress. Especially, astrocytes mediate the bulk of glutamate clearance in the brain via specific membrane transporters (GLAST and GLT1), thereby preventing the occurrence of excitotoxic events. Although glutamate-mediated mechanisms are thought to contribute to nigral dopaminergic neuron degeneration in Parkinson's disease, detailed information on the organization of glia in the substantia nigra is still lacking. The present study was performed to provide quantitative information on the organization of astroglia and on the relationships between astrocytes and excitatory synapses in the rat substantia nigra. Using immunolabeling of GLT1 and confocal imaging, we found that the substantia nigra was filled with a dense meshwork of immunoreactive astrocyte processes. Stereological analysis performed on electron microscope images revealed that the density of immunoreactive astrocyte plasma membranes was substantial, close to 1 μm2/μm3, in the substantia nigra neuropil, both in the pars compacta and the pars reticulata. Excitatory synapses had on average two thirds of their perimeters free from glia, a disposition that may favor transmitter spillover. The density of glutamatergic synapses, as quantified on confocal images by the simultaneous detection of bassoon and of vesicular glutamate transporter 1 or 2, was very low (0.01 and 0.025 per μm3 in the reticulata and compacta subdivisions, respectively). Thus the ratio of GLT1-expressing glial membrane surface to glutamatergic synapses was very high (40–100 μm2), suggesting an efficient regulation of extracellular glutamate concentrations. 相似文献
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Paul C Shick CDR DC USN Staff Oral & Maxillofacial Pathologist Robert B Brannon DDS MSD Associate Professor 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》1998,86(6):720-722
Electrocautery can induce significant alterations in the connective tissues and epithelium of specimens removed for diagnostic or therapeutic purposes. When electrocautery is used during parotid surgery, it can cause an oncocytoid artifact. The alterations described in this article are enlarged, tightly packed serous acinar cells with coarse to granular eosinophilic cytoplasm, distinct cell borders, and round basal nuclei that on cursory microscopic examination resemble oncocytes with respect to morphology. These changes are seen in conjunction with other, more recognized changes secondary to electrocautery and are believed to occur as a consequence of the electrothermal discharge. On the basis of our findings, this artifact is common in parotid surgical specimens and was misdiagnosed as benign oncocytic lesions in 5 cases. 相似文献
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Clifford B. Starr Lt Col USAF DC 《Journal of esthetic and restorative dentistry : official publication of the American Academy of Esthetic Dentistry ... [et al.]》1991,3(6):195-208
Proper management of periodontal tissues is required to achieve predictable long-term success with restorative dental procedures. Forced eruption as well as several surgical techniques may be used to achieve and maintain adequate biologic width during restorative and esthetic dental procedures. The technique that will yield optimal results depends on the relationship between the restoration's margins and the surrounding periodontium. A classification system that describes these interrelationships and provides treatment recommendations is included. 相似文献
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Jesse Lieberman David Goff Jr Flora Hammond Pamela Schreiner H. James Norton Michael Dulin Xia Zhou Lyn Steffen 《Topics in spinal cord injury rehabilitation》2014,20(2):127-136
Background:
The relationship between cardiovascular disease (CVD) risk factors and dietary intake is unknown among individuals with spinal cord injury (SCI).Objective:
To investigate the relationship between consumption of selected food groups (dairy, whole grains, fruits, vegetables, and meat) and CVD risk factors in individuals with chronic SCI.Methods:
A cross-sectional substudy of individuals with SCI to assess CVD risk factors and dietary intake in comparison with age-, gender-, and race-matched able-bodied individuals enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Dietary history, blood pressure, waist circumference (WC), fasting blood glucose, high-sensitivity C-reactive protein (hs-CRP), lipids, glucose, and insulin data were collected from 100 SCI participants who were 38 to 55 years old with SCI >1 year and compared to 100 matched control participants from the CARDIA study.Results:
Statistically significant differences between SCI and CARDIA participants were identified in WC (39.2 vs 36.2 in.; P < .001) and high-density lipoprotein cholesterol (HDL-C; 39.2 vs 47.5 mg/dL; P < .001). Blood pressure, total cholesterol, triglycerides, glucose, insulin, and hs-CRP were similar between SCI and CARDIA participants. No significant relation between CVD risk factors and selected food groups was seen in the SCI participants.Conclusion:
SCI participants had adverse WC and HDL-C compared to controls. This study did not identify a relationship between consumption of selected food groups and CVD risk factors.Key words: cardiovascular disease risk factors, dietary intake, spinal cord injuryCardiovascular disease (CVD) is a leading cause of death in individuals with chronic spinal cord injuries (SCIs).1–5 This is partly because SCI is associated with several metabolic CVD risk factors, including dyslipidemia,6–10 glucose intolerance,6,11–14 and diabetes.15–17 In addition, persons with SCI exhibit elevated markers of inflammation18,19 and endothelial activation20 that are correlated with higher CVD prevalence.21–23 Obesity, and specifically central obesity, another CVD risk factor,24–26 is also common in this population.12,27–29Dietary patterns with higher amounts of whole grains and fiber have been shown to improve lipid abnormalities,30 glucose intolerance, diabetes mellitus,31–34 hypertension,35 and markers of inflammation36 in the general population. These dietary patterns are also associated with lower levels of adiposity.31 Ludwig et al reported that the strong inverse associations between dietary fiber and multiple CVD risk factors – excessive weight gain, central adiposity, elevated blood pressure, hypertriglyceridemia, low high-density lipoprotein cholesterol (HDL-C), high low-density lipoprotein cholesterol (LDL-C), and high fibrinogen – were mediated, at least in part, by insulin levels.37 Whole-grain food intake is also inversely associated with fasting insulin, insulin resistance, and the development of type 2 diabetes.32,38,39Studies in the general population have also shown a positive association between the development of metabolic syndrome as well as heart disease and consumption of a Western diet, a diet characterized by high intake of processed and red meat and low intake of fruit, vegetables, whole grains, and dairy.40,41 Red meat, which is high in saturated fat, has been shown to have an association with adverse levels of cholesterol and blood pressure and the development of obesity, metabolic syndrome, and diabetes.40,42,43Numerous studies have shown that individuals with chronic SCI have poor diet quality.44–49 A Canadian study found that only 26.7% of their sample was adherent to the recommendations about the consumption of fruit, vegetables, and grains from the “Eating Well with Canada’s Food Guide.”44 Individuals with chronic SCI have also been found to have low fiber and high fat intakes when their diets were compared to dietary recommendations from the National Cholesterol Education Program,46 the 2000 Dietary Guidelines for Americans,49 and the recommended Dietary Reference Intakes and the Acceptable Macronutrient Distribution Range.47,48However, unlike in the general population, the relationship between dietary intake and obesity and CVD risk factors is unknown in the chronic SCI population. If a dietary pattern consisting of higher intake of whole grains and dietary fiber is favorably associated with obesity and CVD risk factors in individuals with chronic SCI, then trials of increased intake of whole grains and fiber intake could be conducted to document health benefits and inform recommendations. The purpose of this pilot study is to investigate the association between selected food group intake and CVD risk factors in individuals with chronic SCI as compared to age-, gender-, and race-matched able-bodied individuals enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Data will also be used to plan future studies in the relatively understudied field of CVD and nutrition in individuals with SCI. 相似文献8.
Jennifer M. Lynch Erin M. Buckley Peter J. Schwab Ann L. McCarthy Madeline E. Winters David R. Busch Rui Xiao Donna A. Goff Susan C. Nicolson Lisa M. Montenegro Stephanie Fuller J. William Gaynor Thomas L. Spray Arjun G. Yodh Maryam Y. Naim Daniel J. Licht 《The Journal of thoracic and cardiovascular surgery》2014
9.
Carine Salliot Amélie Denis Emmanuelle Dernis Vincent Andre Aleth Perdriger Jean-David Albert Saloua Mammou Mraghni Isabelle Griffoul-Espitalier Mohamed Hamidou Benoit Le Goff Sandrine Jousse Joulin Thierry Marhadour Christophe Richez Nicolas Poursac Estebaliz Lazaro Stéphanie Rist Anca Corondan Clara Quinten Emilie Ducourau 《Joint, bone, spine : revue du rhumatisme》2018,85(6):741-745
Objectives
The aims of this study in SLE population were (1) to describe ultrasonography (US) joint abnormalities, (2) to estimate the reliability of clinical swollen joint count (C-SJC) and SLEDAI (C-SLEDAI) versus US-SJC and US-SLEDAI scores, (3) to highlight specific patterns of lupus patients with Power Doppler (PD) abnormalities.Method
For this cross-sectional multicenter study, 151 consecutive adult SLE patients were recruited. Evaluation included a clinical standardized joint assessment, B-mode and PD US of 40 joints and 26 tendons blinded for clinical examination. Reliability and agreement between clinical and B-mode US were calculated using the intraclass correlation coefficients (ICC [95% Confidence Interval]).Results
We found a very high frequency of subclinical US abnormalities in asymptomatic patients: 85% of patients without joint symptoms had at least 1 US abnormality. Among them 46 patients (87%) had a history of joint involvement. The most frequent abnormalities were joint effusmaions (108 patients), synovial hypertrophy (SH, 109 patients) and synovitis (61 patients). Joint or tendon PD signal (grade > 1) was found in 44% of patients (67/151). Synovitis were mainly located especially on MCPs and wrists. Even if reliability between clinical and grey-scale US SJC assessments was poor, reliability between clinical and US SLEDAI was good. Comparison between SLE patients with and without PD signal did not show any specific SLE pattern.Conclusion
US may be useful to assess joint involvement in SLE patients but did not significantly change SLEDAI score. 相似文献10.
Phylogenetic analysis of human G9P[8] rotavirus strains circulating in Jiangsu,China between 2010 and 2016 下载免费PDF全文
Cheng Xu MD Jianguang Fu DC Jing Ai MD Jun Zhang MD Cheng Liu BD Xiang Huo MD Changjun Bao MD Yefei Zhu DM 《Journal of medical virology》2018,90(9):1461-1470
Rotavirus A (RVA) is the leading cause of acute viral gastroenteritis in children under 5 years of age worldwide. G9P[8] is a common RVA genotype that has been persistently prevalent in Jiangsu, China. To determine the genetic diversity of G9P[8] RVAs, 7 representative G9P[8] strains collected from Suzhou Children’s Hospital between 2010 and 2016 (named JS2010‐JS2016) were analyzed through whole‐genome sequencing. All evaluated strains showed the Wa‐like constellation G9‐P[8]‐I1‐R1‐C1‐M1‐A1‐N1‐T1‐E1‐H1. Furthermore, phylogenetic analysis revealed that the VP7 genes of all strains clustered into lineage G9‐III and G9‐VI. With the exception of strain JS2012 (P[8]‐4), the VP4 sequences of all strains belonged to the P[8]‐3 lineage. Sequencing further revealed that amino acid substitutions were present in the antigenic regions of the VP7 and VP4 genes of all strains. Moreover, there were multiple substitutions in antigenic sites I and II of the nonstructural protein 4 (NSP4) genes, whereas the other NSP genes were relatively conserved. In conclusion, our phylogenetic analysis of these 7 G9P[8] strains suggests that RVA varied across regions and time. Therefore, our findings suggest that continued surveillance is necessary to explore the molecular evolutionary characteristics of RVA for better prevention and treatment of acute viral gastroenteritis. 相似文献