Evaluation of modified passive haemagglutination assay for Vi antibody estimation in Salmonella typhi infections.

A simple passive haemmagglutination assay (PHA) was developed to detect Vi antibodies, to improve the diagnosis of typhoid fever by small laboratories. The Vi capsular antigen of Salmonella typhi was extracted by alternate alcohol and acetone precipitation. Formalin fixed, sheep red blood cells treated with chromium chloride were sensitised with this Vi antigen and antibodies detected and measured by PHA. The test had a sensitivity of 83.3% among 30 cases of typhoid fever confirmed by culture. The specificity of the test was 94%, making it suitable for use in laboratories without facilities for IFAT or ELISA.     

Laser doppler imaging of menstrual symptoms

In this paper, the skin blood flow for the stomach and forehead regions of 36 female patients with menstrual symptoms was studied using a moorLDI laser Doppler imager in which the results of 6 typical patients are included. The patterns obtained at the two sites are common to all women in the sample who have menstrual symptoms. Cold stress testing was also investigated to see if it was effective in bringing out any skin blood flow fluctuation at these regions caused by menstrual symptoms. Each patient attended two scanning sessions: one before and the other during menstruation. During each session, the patient was scanned three consecutive times, each on the stomach and the forehead skin regions. For each region, the first measurement was a bare scanning whereas for the second and the third, 85% denatured ethanol (cold stress test) was applied onto the required scan areas. It was found that cold stress testing was able to bring out distinct differences in LDI perfusion images before and during menstruation. Results were best captured when perfusion images were taken approximately after 85% denatured ethanol had been applied in two layers for 30 s, allowed to evaporate over the next 5 min (approximately the time taken to obtain one image), reapplied for another 30 s and then finally over the next 30 s allowed to evaporate further. However, it was impossible to deduce conclusively any correlation regarding migraine and skin blood flow since all the patients for this work had menstrual cramps only.     

Distributed cortical networks for focused auditory attention and distraction

We used behavioral measures and functional magnetic resonance imaging (fMRI) to study the effects of parametrically varied task-irrelevant pitch changes in attended sounds on loudness-discrimination performance and brain activity in cortical surface maps. Ten subjects discriminated tone loudness in sequences that also included infrequent task-irrelevant pitch changes. Consistent with results of previous studies, the task-irrelevant pitch changes impaired performance in the loudness discrimination task. Auditory stimulation, attention-enhanced processing of sounds and motor responding during the loudness discrimination task activated supratemporal (auditory cortex) and inferior parietal areas bilaterally and left-hemisphere (contralateral to the hand used for responding) motor areas. Large pitch changes were associated with right hemisphere supratemporal activations as well as widespread bilateral activations in the frontal lobe and along the intraparietal sulcus. Loudness discrimination and distracting pitch changes activated common areas in the right supratemporal gyrus, left medial frontal cortex, left precentral gyrus, and left inferior parietal cortex.     

The alterations of N-Methyl-D-aspartate receptor expressions and oxidative DNA damage in the CA1 area at the early time after ischemia-reperfusion insult

Delayed neuronal death in the CA1 of the hippocampus following global ischemia has been evoked by both the activation of N-methyl-D-aspartate receptor (NR) and the generate reactive oxygen species in the neurons. In the present study, we investigated whether oxidative DNA damages may be correlated with NR subunits (NR1 and NR2A/B) expression following ischemia insults in vivo. Thirty minutes after ischemia-reperfusion, the intensities of both NR and 8-hydroxy-2'-deoxyguanosine (8-OHdG) immunoreactivities were markedly increased in neurons of CA1. However, NR2A/B and 8-OHdG immunoreactivities were enhanced in CA1 over 24 h after ischemia although NR1 immunoreactivity was decreased. These results suggest that oxidative stress and excitotoxicity in the CA1 may simultaneously trigger neuronal damages at early time after ischemia, and free radical damage including oxidative DNA damage may eventually promote the delayed neuronal death in this region.     

Radioprotective Effect of Whey Hydrolysate Peptides against γ-Radiation-Induced Oxidative Stress in BALB/c Mice

Radiation therapy is widely used in the treatment of tumor diseases, but it can also cause serious damage to the body, so it is necessary to find effective nutritional supplements. The main purpose of this study is to evaluate the protective effect of whey hydrolysate peptides (WHPs) against ⁶⁰Coγ radiation damage in mice and explore the mechanism. BALB/c mice were given WHPs by oral gavage administration for 14 days. Then, some mice underwent a 30-day survival test after 8 Gy radiation, and other mice received 3.5 Gy radiation to analyze the changes in body weight, hematology and bone marrow DNA after three and 14 days. In addition, through further analysis of the level of oxidative stress and intestinal barrier function, the possible mechanism of the radioprotective effect of WHPs was explored. The study found WHPs can prolong survival time, restore body weight, and increase the number of peripheral blood white blood cells and bone marrow DNA content in irradiated mice. In addition, WHPs can significantly improve the antioxidant capacity, inhibit pro-inflammatory cytokines and protect the intestinal barrier. These results indicate that WHPs have a certain radioprotective effect in mice, and the main mechanism is related to reducing oxidative damage.     

Machine Learning Algorithms to Predict Mortality and Allocate Palliative Care for Older Patients With Hip Fracture

ObjectivesTo evaluate a machine learning model designed to predict mortality for Medicare beneficiaries aged >65 years treated for hip fracture in Inpatient Rehabilitation Facilities (IRFs).DesignRetrospective design/cohort analysis of Centers for Medicare & Medicaid Services Inpatient Rehabilitation Facility–Patient Assessment Instrument data.Setting and ParticipantsA total of 17,140 persons admitted to Medicare-certified IRFs in 2015 following hospitalization for hip fracture.MeasuresPatient characteristics include sociodemographic (age, gender, race, and social support) and clinical factors (functional status at admission, chronic conditions) and IRF length of stay. Outcomes were 30-day and 1-year all-cause mortality. We trained and evaluated 2 classification models, logistic regression and a multilayer perceptron (MLP), to predict the probability of 30-day and 1-year mortality and evaluated the calibration, discrimination, and precision of the models.ResultsFor 30-day mortality, MLP performed well [acc = 0.74, area under the receiver operating characteristic curve (AUROC) = 0.76, avg prec = 0.10, slope = 1.14] as did logistic regression (acc = 0.78, AUROC = 0.76, avg prec = 0.09, slope = 1.20). For 1-year mortality, the performances were similar for both MLP (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.96) and logistic regression (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.95).Conclusion and ImplicationsA scoring system based on logistic regression may be more feasible to run in current electronic medical records. But MLP models may reduce cognitive burden and increase ability to calibrate to local data, yielding clinical specificity in mortality prediction so that palliative care resources may be allocated more effectively.     

HIV阴性儿童马尔尼菲篮状菌病2例临床分析并文献复习

 目的 总结2例人类免疫缺陷病毒（HIV）阴性儿童马尔尼菲篮状菌病（TSM）患儿的临床特征。方法 分析某儿童医院收治的2例HIV阴性TSM患儿的临床特点及实验室资料、存在的基础疾病,并复习相关文献,总结TSM感染患儿的临床特征及诊治经验。结果 2例HIV阴性TSM患儿中病例1以右下肢肿块为首发症状,1个月余后才出现发热及咳嗽,误诊为结核感染;病例2以发热、三系减少及肝脾、淋巴结大等表现起病。病例1行基因检测为STAT1基因突变,病例2有反复灰指甲及口腔溃疡病史,均行血、骨髓培养及淋巴结活检确诊。病例1先后予以伏立康唑、两性霉素B脂质体静脉滴注,伊曲康唑口服维持治疗,共治疗1年后停药;病例2一直予以伏立康唑治疗（先静脉滴注后口服）,共7个月后停药,均无复发。结论 TSM可发生在HIV阴性儿童,且可存在STAT1基因突变。对于治疗效果差的患儿,应尽早行培养或组织活检以明确诊断,并积极查找TSM可能存在的基础疾病,以到达早期诊断、早期治疗和改善预后的目的。     

Waning Antibody Responses in Asymptomatic and Symptomatic SARS-CoV-2 Infection

We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response.     

食管癌血管生成与淋巴结转移的关系

目的 探讨食管因管生成与淋巴结转移的关系,方法 采用免疫组织化学的方法检测了1994－1995年手术切除的50例食管癌病人石蜡标本中微血管密度和血管内皮生长因子及受体蛋白的表达。其中有食管旁淋巴结转移者18例,胃左动脉旁淋巴结转移15例。光镜下行MVD、VEGF、Flt、KDR蛋白表达细胞的计数。结果 食管旁和胃左动脉旁淋巴结转移组的微血管密度（MVD）、血管内皮生长因子（VEGF）、血管同皮生长因子受体（Flt、KDR）蛋白表达均高于未转移组,结论 食管癌中MVD、VEGF、Flt、KDR蛋白表达与肿瘤转移行为密切相关,有可能作为判定肿瘤生物学行为、转移潜能及预后的指标。     

老年Ⅱ型糖尿病患者血清NO水平与肾功能变化的相关性研究

目的探讨一氧化氮(NO)在老年Ⅱ型糖尿病肾病发病过程中的变化规律及其与肾功能的关系。方法采用Griess法检测48例Ⅱ型DM病人血清NO值在水平及与肾功能有关的指标,并与17例正常人进行比较,结果血清NO值在正常尿蛋白(DMI)组(88.86±9.61umol/l)和微量尿蛋白(DMII)组(90.00±17.94umol/l)明显高于对照组(56.70±9.53umol/l)(P＜0.01),至临床肾病期血浆NO浓度明显降低(63.25±8.64umol/l)(P＞0.05);NO与BUN、BCR呈负相关,而与CCR呈正相关。结论血清NO水平的动态变化与Ⅱ型DM肾病的发生、发展有密切联系。