Arrangement of Excitatory Synaptic Inputs on Dendrites of the Medial Superior Olive

Neurons in the medial superior olive (MSO) detect 10 µs differences in the arrival times of a sound at the two ears. Such acuity requires exquisitely precise integration of binaural synaptic inputs. There is substantial understanding of how neuronal phase locking of afferent MSO structures, and MSO membrane biophysics subserve such high precision. However, we still lack insight into how the entirety of excitatory inputs is integrated along the MSO dendrite under sound stimulation. To understand how the dendrite integrates excitatory inputs as a whole, we combined anatomic quantifications of the afferent innervation in gerbils of both sexes with computational modeling of a single cell. We present anatomic data from confocal and transmission electron microscopy showing that single afferent fibers follow a single dendrite mostly up to the soma and contact it at multiple (median 4) synaptic sites, each containing multiple independent active zones (the overall density of active zones is estimated as 1.375 per μm²). Thus, any presynaptic action potential may elicit temporally highly coordinated synaptic vesicle release at tens of active zones, thereby achieving secure transmission. Computer simulations suggest that such an anatomic arrangement boosts the amplitude and sharpens the time course of excitatory postsynaptic potentials by reducing current sinks and more efficiently recruiting subthreshold potassium channels. Both effects improve binaural coincidence detection compared with single large synapses at the soma. Our anatomic data further allow for estimation of a lower bound of 7 and an upper bound of 70 excitatory fibers per dendrite.SIGNIFICANCE STATEMENT Passive dendritic propagation attenuates the amplitude of postsynaptic potentials and widens their temporal spread. Neurons in the medial superior olive, with their large bilateral dendrites, however, can detect coincidence of binaural auditory inputs with submillisecond precision, a computation that is in stark contrast to passive dendritic processing. Here, we show that dendrites can counteract amplitude attenuation and even decrease the temporal spread of postsynaptic potentials, if active subthreshold potassium conductances are triggered in temporal coordination along the whole dendrite. Our anatomic finding that axons run in parallel to the dendrites and make multiple synaptic contacts support such coordination since incoming action potentials would depolarize the dendrite at multiple sites within a brief time interval.     

上海社区老年人代谢综合征患者的中医体质分析＊

目的 了解上海社区老年人代谢综合征（MS）的危险因素及中医体质分布情况，为预防MS及其并发症的发生提供数据参考。方法 采用九种体质问卷，对社区1158例MS患者进行中医体质及危险因素分析。结果 女性人群中高血脂病史和骨质疏松症病史所占比例高于男性。MS各组成成分中，女性腰围、高密度脂蛋白以及甘油三酯的比例明显高于男性，并且有显著性差异。2463例老年人中MS患者1158例（47.02%），MS患者主要体质为痰湿质587例（50.69%），其次为平和质262例（22.63%），次之为阴虚质106（9.15%）。通过logistics回归矫正生活方式，既往史以及腰围、血压、血糖和血脂等MS高危因素后，发现痰湿质人群MS的患病率是平和质人群的1.6倍。结论 痰湿质是MS人群的独立危险因素，通过饮食和运动干预来纠正或改善痰湿质，降低MS的患病率，提高老年人的生活质量。     

Developing normal number of small segments-activity clouds of the electromyography interference pattern

Guillain-Barré syndrome (GBS) is an inflammatory polyradiculoneuropathy associated with numerous viral infections. Recently, there have been many case reports describing the association between coronavirus disease-2019 (COVID-19) and GBS, but much remains unknown about the strength of the association and the features of GBS in this setting. We reviewed 37 published cases of GBS associated with COVID-19 to summarize this information for clinicians and to determine whether a specific clinical or electrodiagnostic (EDx) pattern is emerging. The mean age (59 years), gender (65% male), and COVID-19 features appeared to reflect those of hospitalized COVID-19 patients early in the pandemic. The mean time from COVID-19 symptoms to GBS symptoms was 11 days. The clinical presentation and severity of these GBS cases was similar to those with non–COVID-19 GBS. The EDx pattern was considered demyelinating in approximately half of the cases. Cerebrospinal fluid, when assessed, demonstrated albuminocytologic dissociation in 76% of patients and was negative for severe acute respiratory distress syndrome–coronavirus-2 (SARS-CoV-2) in all cases. Serum antiganglioside antibodies were absent in 15 of 17 patients tested. Most patients were treated with a single course of intravenous immunoglobulin, and improvement was noted within 8 weeks in most cases. GBS-associated COVID-19 appears to be an uncommon condition with similar clinical and EDx patterns to GBS before the pandemic. Future studies should compare patients with COVID-19–associated GBS to those with contemporaneous non–COVID-19 GBS and determine whether the incidence of GBS is elevated in those with COVID-19.     

Patterns of Uveitis among Patients Attending Jimma University Department of Ophthalmology,Jimma, Ethiopia

ABSTRACT

Introduction: Uveitis is an important cause of blindness and ocular morbidity in the world. The patterns of uveitis have not been well characterized in sub-Saharan Africa.

Purpose: To describe the characteristics of uveitis among patients presenting to Jimma University Department of Ophthalmology (JUDO) from July 2013 to December 2014.

Methods: This hospital-based prospective cross-sectional study included all new uveitis patients visiting JUDO outpatient department during the study period.

Results: Among 98 patients diagnosed with uveitis, anterior uveitis was found in 74.5% of patients. Majority of the patients, 83.7%, had unilateral uveitis. A uveitis syndrome was identified in 22.5% of cases; of these 15 (68.2%) were infectious. Herpes simplex uveitis was the commonest infectious cause (53.3%) while Toxoplasmosis was the most common cause of posterior uveitis (60%).

Conclusion: Anterior uveitis was the most common pattern found among uveitis patients. Herpes simplex and toxoplasmic chorioretinitis were the most common-identified infectious causes.     

Association between sleep period time and dietary patterns in Brazilian schoolchildren aged 7–13 years

ObjectivesTo assess the association between sleep period time and dietary patterns (DPs) in Brazilian schoolchildren aged 7–13 years.MethodsSleep data of 1019 children were obtained from a questionnaire completed by parents/guardians. Food consumption, physical activity, and screen-based activity were assessed through the validated Web-CAAFE questionnaire. Latent profile analysis was used to identify dietary patterns. Associations between sleep period time and dietary patterns were analyzed by multinomial logistic regression, and the average marginal effect of sleep period time on the probability of adherence to dietary patterns was determined.ResultsOverall, 11.4% of children had inadequate sleep period time (<9 h per day). Three mutually exclusive dietary patterns were identified: “Monotonous” characterized by high consumption of pasta, instant pasta, sweets, and hamburgers/hot dog/pizza/salty snacks; “Traditional” characterized by high consumption of rice, vegetables, green leaves, beans, manioc flour, maize/potatoes, and meats; and “Dairy, bread, green leaves, maize/potatoes and sausage”. The likelihood of adherence to the “Dairy, bread, green leaves, maize/potatoes and sausages” DP decreased by 0.026 as sleep period time increased by 1 h per day. For a sleep period time of more than 10 h per day, the average marginal effect of sleep period time on the likelihood of adherence to the this dietary pattern was significant and negative.ConclusionsSleep period time was inversely associated with adherence to the “Dairy, bread, green leaves, maize/potatoes and sausages” DP; children who slept more than 10 h per day were less likely to present this pattern.     

Ischémie reperfusion en transplantation rénale

Ischemia-reperfusion injury is an inescapable phenomenon in kidney transplantation. It combines lesional processes of biochemical origin associated with oxydative stress and of immunological origin in connection with the recruitment and activation of innate immunity cells. Histological lesions associate acute tubular necrosis and interstitial œdema, which can progress to interstitial fibrosis. The extent of these lesions depends on donor characteristics (age, expanded criteria donor, etc.) and cold ischemia time. In the short term, ischemia-reperfusion results in delayed recovery of graft function. Cold ischemia time also impacts long-term graft survival. Preclinical models, such as murine and porcine models, have furthered understanding of the pathophysiological mechanisms of ischemia-reperfusion injury. Due to its renal anatomical proximity to humans, the porcine model is relevant to assessment of the molecules administered to a donor or recipient, and also of additives to preservation solutions. Different donor resuscitation and graft perfusion strategies can be studied. In humans, prevention of ischemia-reperfusion injury is a research subject as concerns donor conditioning, additive molecules in preservation solutions, graft reperfusion modalities and choice of the molecules administered to the recipient. Pending significant advances in research, the goal is to achieve the shortest possible cold ischemia time.     

The association of dietary patterns and cardiorespiratory fitness: A systematic review

AimsIn comparison to the traditional risk factors of cardiovascular diseases, little is known about the interaction between diet and cardiorespiratory fitness (CRF). The present systematic review aimed to provide comprehensive evidence regarding the relationship between the dietary patterns (DPs) with CRF in both children and adults.Data synthesisDatabases of PubMed, Scopus, and Web of Science were searched from inception up to December 2019. All observational studies that had extracted DPs using a posteriori and/or a priori methods, as well as had assessed CRF as the outcome, were eligible for inclusion in the review. Eleven studies (1 longitudinal and 10 cross-sectional studies) comprising a total of 198,271 subjects were included. There was considerable heterogeneity between studies in terms of the extracted DPs, their food items as well as the statistical reporting outcomes; which all made comparisons between the studies difficult. Despite some inconsistent results, overall there was a positive association between the DPs that were highly loaded with fruits and vegetables, as well as closer adherence to the high-quality diets particularly the Mediterranean diet, with higher values of CRF. While, an inverse association was found for unhealthy DPs that were generally characterized by a high intake of refined grains, sweets, meats, processed foods, and high-fat dairy products.ConclusionOverall, the evidence indicates the high-quality diets that are highlighted in the national dietary guidelines are associated with an optimal CRF. However, these findings should be confirmed by rigorous prospective and interventional studies.     

子宫颈腺癌Silva分型的临床病理意义及研究现状

子宫颈腺癌与HPV感染高度相关，近期提出的Silva分型相较于目前的诊疗依据，能更好地预测子宫颈腺癌的预后并指导临床治疗。文章就当前子宫颈腺癌的诊治现状、Silva分型的临床病理意义及相关研究进展进行阐述和分析。