Identification of the source of A (H10N8) virus causing human infection

A novel H10N8 influenza A virus has been detected in three humans in China since December 2013. Although this virus was hypothesized to be a novel reassortant among influenza viruses from wild birds and domestic poultry, its evolutionary path leading to human infection is unknown. Sporadic surveillance at the live poultry market (LPM) suspected to be the source of infection for the first H10N8 patient has shown a gradual increase in influenza virus prevalence culminating with a predominance of H10N8 viruses. Influenza viruses detected in the LPM up to 8 months prior to human infection contributed genetic components to the zoonotic virus. These H10N8 viruses have continued to evolve within this LPM subsequent to the human infection, and continuous assessments of these H10N8 viruses will be necessary. Serological surveillance showed that the virus appears to have been present throughout the LPM system in Nanchang, China. Reduction of the influenza virus burden in LPMs is essential in preventing future emergence of novel influenza viruses with zoonotic and pandemic potential.     

Spontaneous bacterial peritonitis from Salmonella: an unusual bacterium with unusual presentation

Spontaneous bacterial peritonitis (SBP) is a common cause of morbidity and mortality in patients with advanced cirrhosis and portal hypertension. While gram-negative rods and Enterococcus species are the common offending organisms, Salmonella has also been recognized as a rare and atypical offending organism. Atypical features of Salmonella SBP include both its occurrence in cirrhotic patients with immunosuppressive state and its lack of typical neutroascitic response. Diagnosis is often delayed as it requires confirmation from ascitic fluid culture. We report a case of Salmonella SBP occurring in a patient with decompensated cryptogenic cirrhosis with concurrent low-grade non-Hodgkin lymphoma and prior treatment with rituximab. Physicians should be aware of the atypical presentation, especially in cirrhotic patients who are immunosuppressed.     

肝移植5年后生存影响因素分析

目的评估我院肝移植患者长期生存情况,分析肝移植5年后生存质量的影响因素。方法回顾性分析2000年3月至2007年8月完成46例生存超过5年的肝移植病例,分析死亡原因、各种并发症情况。结果生存超过5年的46例患者中,死亡4例,其中胆道并发症2例,重症乙型肝炎1例,心肌梗塞1例,各种并发症:高脂血症8例,高血压7例,糖尿病3例,胆道并发症6例,乙肝复发3例,肾功能损害2例,心肌梗塞1例。结论胆道并发症、乙肝复发及免疫抑制剂副作用是影响肝移植5年后生存质量的主要因素,加强多学科长期临床随访指导,低剂量免疫抑制剂联合应用是提高肝移植5年后生存质量的重要因素。     

Cross sectional survey of Varicella-Zoster virus and measles seropositivity in people living with HIV in a Parisian suburb and a review of current immunization guidelines

According to evidence-based guidelines, vaccines against measles and varicella are generally recommended to susceptible HIV-positive patients, as long as they are not severely immunocompromised. However, routine screening to determine serologic status is not recommended. We conducted a seroprevalence study of anti-measles and anti-Varicella-Zoster virus (VZV) antibodies in adults living with HIV (PLWHA) consulting at Avicenne University Hospital in a Parisian suburb. Sera were collected in years 2018–2020 and tested by commercial immunoassays in 268 patients. Most of the patients were born in Sub-Saharan Africa (55 %) and only 23 % in Europe. Measles and varicella seropositivity were present respectively in 91.4 % and 96.2 % of patients. One patient in ten was seronegative to at least one of tested diseases. In the univariate analysis, only younger age (p = 0.027) was associated with a higher risk of measles seronegativity, while shorter time since arrival in France (p < 0.001) and shorter time since HIV discovery (p = 0.007) were associated with a higher risk of VZV seronegativity. In multivariate analysis no association was found. This study highlights the absence of specific risk factors for VZV and measles seronegativity in PLWHA and supports the importance of routine screening, in order to increase immunization rates and reduce risk of complications.     

Real‐Time Visualization of Platelet Interaction With Micro Structured Surfaces

Improving the hemocompatibility of artificial implants by micro structuring their surfaces has shown promising results, but the mechanisms which lead to this improvement are not yet understood. Therefore, we built a test setup for real‐time visualization of platelet interaction with a plain and two micro structured surfaces. The micro structures, defined by the distance of the plain surface area between the structures, were chosen to be 3 and 30 μm, representing a positive and a negative effect on the hemocompatibility. The main part of the test setup was a flow chamber containing films of low density polyethylene (LDPE) with the differently structured surfaces. For different wall shear stresses, no considerable differences were observed in the platelet‐surface interaction for all surface types. Whereas, major differences in flow behavior were observed when comparing the surfaces to each other. The platelets “rolled” along the smooth surface, being in constant contact with the surface material. Although the platelets “rolled” over the surface with small structures as well, they were only in contact with the tips of the structure and therefore had less surface contact with the foreign material. The increased distance and height of the structures of the last surface led to a trapping of platelets between the structures. This resulted in a longer contact time with the foreign material as well as a larger contact area, which both increase the risk of platelet activation, adhesion, and finally clotting. Our results showed the mechanisms which lead to these effects and thus revealed why micro structuring of surfaces impacts the hemocompatibility. Furthermore, we established a test setup which can be used for future investigations on the platelet‐structure interactions.     

长方案控制性促排卵过程中晚卵泡期孕酮变化趋势对体外受精-胚胎移植结局的影响

目的:探讨在控制性卵巢刺激(COS)周期中晚卵泡期孕酮(P)水平变化趋势对体外受精-胚胎移植(IVF-ET)结局的影响。方法:回顾分析2013年1月至2014年6月在我中心行IVF-ET长方案助孕治疗的676个周期。按促排卵中晚卵泡期起始日(主导卵泡直径达13mm日)与人绒毛膜促性腺激素(HCG)注射日孕酮水平变化,分为升高趋势组和降低趋势组;按HCG日孕酮水平是否1.0ng/ml将升高趋势组和降低趋势组中新鲜移植周期分别分为A组(P≤1ng/ml)、B组(P1ng/ml)和C组(P≤1ng/ml)、D组(P1ng/ml)。结果:(1)升高趋势组与降低趋势组的卵裂率、优质胚胎率比较,差异有统计学意义(99.65%vs 99.00%,70.57%vs 63.09%;P0.05);(2)A组与B组的临床妊娠率、活产率比较,差异有统计学意义(56%vs 43.00%;50%vs 37.76%,P0.05);C组与D组的临床妊娠率、活产率比较,差异无统计学意义(P0.05)。结论:IVF-ET长方案周期中,COS过程中孕酮变化呈升高趋势的优质胚胎率较降低趋势高;新鲜移植周期,P呈升高趋势时,HCG日P1.0ng/ml,活产率下降;呈降低趋势时,HCG日P水平不影响活产率。     

Natural Tregs, CD4+CD25+ inhibitory hybridomas, and their cell contact dependent suppression

The natural CD4+CD25+ T regulatory (Treg) lymphocyte has emerged as a critical cell for controlling immune responses to self, foreign proteins, and pathogens. Identified initially by the constitutive expression of CD4 and CD25, natural Tregs suppress a variety of immune cells and responses, including CD4+CD25− proliferation and IL-2 production, and CD8 cell proliferation, IFNγ production and CTL activity. Although natural Tregs require activation with specific antigen to attain their suppressive phenotype, once activated they execute inhibition in an antigen specific as well as non-specific (bystander) fashion. Treg suppression depends on IL-2, CD25, and cell:cell contact. The use of live cell imaging in vivo and in vitro to visualize the dynamic cell:cell interactions involving natural Tregs as well as the CD4+CD25+ Treg inhibitory hybridoma RD6 has refined the mechanistic models of contact dependent Treg suppression.     

Automated live cell screening system based on a 24-well-microplate with integrated micro fluidics

In research, pharmacologic drug-screening and medical diagnostics, the trend towards the utilization of functional assays using living cells is persisting. Research groups working with living cells are confronted with the problem, that common endpoint measurement methods are not able to map dynamic changes. With consideration of time as a further dimension, the dynamic and networked molecular processes of cells in culture can be monitored. These processes can be investigated by measuring several extracellular parameters. This paper describes a high-content system that provides real-time monitoring data of cell parameters (metabolic and morphological alterations), e.g., upon treatment with drug compounds. Accessible are acidification rates, the oxygen consumption and changes in adhesion forces within 24 cell cultures in parallel. Addressing the rising interest in biomedical and pharmacological high-content screening assays, a concept has been developed, which integrates multi-parametric sensor readout, automated imaging and probe handling into a single embedded platform. A life-maintenance system keeps important environmental parameters (gas, humidity, sterility, temperature) constant.