Взаимодействие диатомовых водорослей Pseudo-nitzschia hasleana и Thalassiosira pseudonana в смешанной культуре

Представители рода Pseudo-nitzschia (Bacillariophyta) вызывают цветения в разных районах Мирового океана, поэтому важно знать экологические особенности этих видов, в том числе то, как они взаимодействуют с другими видами одноклеточных водорослей. Кроме того, необходима методика быстрой идентификации данных водорослей в среде. В связи с этим нами оценена динамика численности клеток Pseudo-nitzschia hasleana и Thalassiosira pseudonana в моно- и смешанных культурах путём их прямого подсчёта в камере Нажотта. Также проанализированы температурные кривые флуоресценции хлорофилла a, полученные методом лазерно-индуцированной флуоресценции в температурной камере. Опыты проводили в течение 14 суток. Показано, что P. hasleana оказывала различное действие на T. pseudonana в зависимости от начальной численности T. pseudonana. При начальной концентрации 0,8 × 104 кл.·мл−1 происходила выраженная стимуляция роста этой диатомовой водоросли. При начальных концентрациях 1,6 × 104 и 3,2 × 104 кл.·мл−1 отмечено ингибирование её роста. В смешанной культуре T. pseudonana оставалась в стационарной фазе роста, тогда как в монокультуре популяция входила в фазу отмирания к 14-м суткам опыта. T. pseudonana ингибировала рост P. hasleana. Эксперимент с совместным культивированием P. hasleana и T. pseudonana показал, что на флуоресценцию хлорофилла a смеси оказывает большее воздействие та микроводоросль, концентрация которой значительно выше. Флуоресцентный сигнал двух культивируемых отдельно монокультур потенциально может быть использован для их поиска в смеси

The impact of terahertz radiation on an extremophilic archaean Halorubrum saccharovorum proteome

Nonthermal effects of terahertz radiation on living objects are currently intensely studied, as more sources of this radiation type and devices employing it are being constructed. Terahertz radiation is increasingly used in security and inspection systems, medical and scientific appliances due to its low quant energy, which does not cause severe effects on organisms as other radiation types with higher quant energies do. The aim of this study was the identification of protein complexes participating in the response of the archaea Halorubrum saccharovorum H3 isolated from an extreme natural environment to terahertz radiation. We developed a microfluidic system for irradiation of bacterial and archaeal cultures with terahertz radiation and performed a 5-hour-long exposure of H. saccharovorum to terahertz radiation at a wavelength of 130 μm and a power density of 0.8 Wt per cm2 for 5 h. We identified under- or overexpressed proteins in response to terahertz radiation using 2D electrophoresis with subsequent MALDI-TOF mass spectrometry. A total of 16 differentially expressed protein fractions with at least 1.5-fold changes in expression level were detected. The obtained data suggest that Halorubrum cells respond to exposure to terahertz radiation by expression changes in gene products involved in translation regulation

Cause of Death and Predictors of All-Cause Mortality in Anticoagulated Patients With Nonvalvular Atrial Fibrillation : Data From ROCKET AF

M. Kaste on työryhmän ROCKET AF Steering Comm jäsen.Background-Atrial fibrillation is associated with higher mortality. Identification of causes of death and contemporary risk factors for all-cause mortality may guide interventions. Methods and Results-In the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) study, patients with nonvalvular atrial fibrillation were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards regression with backward elimination identified factors at randomization that were independently associated with all-cause mortality in the 14 171 participants in the intention-to-treat population. The median age was 73 years, and the mean CHADS(2) score was 3.5. Over 1.9 years of median follow-up, 1214 (8.6%) patients died. Kaplan-Meier mortality rates were 4.2% at 1 year and 8.9% at 2 years. The majority of classified deaths (1081) were cardiovascular (72%), whereas only 6% were nonhemorrhagic stroke or systemic embolism. No significant difference in all-cause mortality was observed between the rivaroxaban and warfarin arms (P=0.15). Heart failure (hazard ratio 1.51, 95% CI 1.33-1.70, P= 75 years (hazard ratio 1.69, 95% CI 1.51-1.90, P Conclusions-In a large population of patients anticoagulated for nonvalvular atrial fibrillation, approximate to 7 in 10 deaths were cardiovascular, whereasPeer reviewe

Host hindrance to HIV-1 replication in monocytes and macrophages

Monocytes and macrophages are targets of HIV-1 infection and play critical roles in multiple aspects of viral pathogenesis. HIV-1 can replicate in blood monocytes, although only a minor proportion of circulating monocytes harbor viral DNA. Resident macrophages in tissues can be infected and function as viral reservoirs. However, their susceptibility to infection, and their capacity to actively replicate the virus, varies greatly depending on the tissue localization and cytokine environment. The susceptibility of monocytes to HIV-1 infection in vitro depends on their differentiation status. Monocytes are refractory to infection and become permissive upon differentiation into macrophages. In addition, the capacity of monocyte-derived macrophages to sustain viral replication varies between individuals. Host determinants regulate HIV-1 replication in monocytes and macrophages, limiting several steps of the viral life-cycle, from viral entry to virus release. Some host factors responsible for HIV-1 restriction are shared with T lymphocytes, but several anti-viral mechanisms are specific to either monocytes or macrophages. Whilst a number of these mechanisms have been identified in monocytes or in monocyte-derived macrophages in vitro, some of them have also been implicated in the regulation of HIV-1 infection in vivo, in particular in the brain and the lung where macrophages are the main cell type infected by HIV-1. This review focuses on cellular factors that have been reported to interfere with HIV-1 infection in monocytes and macrophages, and examines the evidences supporting their role in vivo, highlighting unique aspects of HIV-1 restriction in these two cell types

Widespread scrofuloderma: a case study

The authors present a case study of scrofuloderma in a female patient aged 55; the patient’s condition was of interest due to the prevalence of the pathology and long-term (25 years) undiagnosed skin tuberculosis as a result of problems with the diagnostics of this localization of tuberculosis