Exploring the ultrashort pulse laser parameter space for membrane permeabilisation in mammalian cells.

The use of ultrashort femtosecond pulsed lasers to effect membrane permeabilisation and initiate both optoinjection and transfection of cells has recently seen immense interest. We investigate femtosecond laser-induced membrane permeabilisation in mammalian cells as a function of pulse duration, pulse energy and number of pulses, by quantifying the efficiency of optoinjection for these parameters. Depending on pulse duration and pulse energy we identify two distinct membrane permeabilisation regimes. In the first regime a nonlinear dependence of order 3.4-9.6 is exhibited below a threshold peak power of at least 6 kW. Above this threshold peak power, the nonlinear dependence is saturated resulting in linear behaviour. This indicates that the membrane permeabilisation mechanism requires efficient multiphoton absorption to produce free electrons but once this process saturates, linear absorption dominates. Our experimental findings support a previously proposed theoretical model and provide a step towards the optimisation of laser-mediated gene delivery into mammalian cells.Publisher PDFPeer reviewe

VALIDATION OF REAL-TIME REVERSE TRANSCRIPTION POLYMERASE CHAIN REACTION FOR INDIRECT ASSESSMENT OF FMD VIRUS TITRE

Procedure for validation of the method for indirect assessment of cultural FMD virus titre (T FMDV) in raw materials used for vaccine production with real time reverse transcription polymerase chain reaction (RT-PCRrt) based on determined amplifcation threshold cycle value (Ct) using linear regression model, TFMDV= –0.2956Ct+ 11.4650, is described in the paper. Testing results for 390 samples of cultural FMD virus were analyzed and basic validation characteristics of the proposed method: specifcity, accuracy, precision, limit of detection and limit of quantifcation, application scope and linearity, were defned. Validation results for the method for indirect assessment of FMD virus titre with RT-PCRrt met the acceptance criteria

L-arginine supplementation does not enhance blood flow and muscle performance in healthy and physically active older women

Purpose: The purpose of this study was to examine the effects of acute l-arginine (l-arg) supplementation on peripheral vasodilatation and muscle performance in older women. Methods: In a double-blind, randomized, placebo-controlled study, 20 elderly women were randomly assigned in a double-blind fashion to either an l-arg (ARG, N = 10) or placebo (PLA, N = 10) group. During the first visit, both groups underwent a Doppler ultrasound exam (to assess the femoral artery vasodilatation) at rest (baseline), and immediately before and after the isokinetic strength test (performed at 80 min after supplementation). On the second and third visits, the groups completed a battery of muscle performance tests (to assess the isometric and functional strength), initiated at the same time point (80 min after supplementation). Results: The femoral artery blood flow (ARG: 443.9 ± 42.8 vs. PLA: 373.1 ± 40.8 ml/min; P > 0.05) and area (ARG: 0.45 ± 0.03 vs. PLA: 0.41 ± 0.02 cm2; P > 0.05) were similar between the groups at basal conditions, and they remained unchanged after supplementation. Following exercise, blood flow increased ~160 % above the basal level, and there was no significant (P > 0.05) difference between the ARG and PLA groups. Additionally, there were no significant (P > 0.05) differences between the ARG and PLA groups for any strength variable (isokinetic, isometric, and functional). Conclusion: These results show that acute l-arg supplementation provides no ergogenic effect on blood flow and muscle performance in older women

Proinflammatory and anti-inflammatory cytokine profiles in psoriasis: use as laboratory biomarkers and disease predictors

Proinflammatory and anti-inflammatory cytokine profiles in psoriasis: use as laboratory biomarkers and disease predictor

The Prevalence of Viral Pathogens among Bats in Kazakhstan

Bats carry thousands of viruses from 28 different families. To determine the presence of various pathogens in bat populations in Kazakhstan, 1149 samples (393 oropharyngeal swabs, 349 brain samples, 407 guano) were collected. The samples were collected from four species of bats (Vespertilio murinus, Nyctalus noctula, Myotis blythii, Eptesicus serotinus) in nine regions. The Coronavirus RNA was found in 38 (4.75%) samples, and the rabies virus in 27 (7.74%) samples from bats. Coronaviruses and the rabies virus were found in bats in six out of nine studied areas. The RNAs of SARS-CoV-2, MERS, TBE, CCHF, WNF, influenza A viruses were not detected in the bat samples. The phylogeny of the RdRp gene of 12 samples made it possible to classify them as alphacoronaviruses and divide them into two groups. The main group (n = 11) was closely related to bat coronaviruses from Ghana, Zimbabwe and Kenya. The second group (n = 1) was closely related to viruses previously isolated in the south of Kazakhstan. The phylogeny of the N gene sequence from a bat from west Kazakhstan revealed its close relationship with isolates from the Cosmopolitan group of rabies viruses (Central Asia). These results highlight the need for a continuous monitoring of volatile populations to improve the surveillance and detection of infectious diseases

Cell adhesion molecules and plasminogen activator inhibitor type-1 (PAI-1) in patients with rheumatoid arthritis: influence of metabolic syndrome

Cell adhesion molecules and plasminogen activator inhibitor type-1 (PAI-1) in patients with rheumatoid arthritis: influence of metabolic syndrom

Metabolic syndrome and the decreased levels of uric acid by leflunomide favor redox imbalance in patients with rheumatoid arthritis

Oxidative stress plays a role in the pathophysiology of rheumatoid arthritis (RA). The aim of the present study was to verify the influence of metabolic syndrome (MetS) and disease-modifying antirheumatic drugs on nitrosative and oxidative biomarkers in patients with RA. A total of 177 patients with RA and 150 healthy volunteers participated in this study, which measured lipid hydroperoxides, advanced oxidation protein products (AOPP), nitric oxide metabolites (NOx), carbonyl protein, total radical-trapping antioxidant parameter (TRAP), uric acid (UA), and C-reactive protein (CRP). NOx and the NOx/TRAP ratio were significantly increased in RA, while no significant differences in lipid hydroperoxides, AOPP, UA, and TRAP levels were found between both groups. Treatment with leflunomide was associated with increased levels of carbonyl protein, and lowered levels in TRAP and UA, while the NOx/TRAP ratio further increased. NOx and the NOx/TRAP ratio were significantly higher in women than in men, while TRAP and UA were significantly lower in women. MetS was accompanied by increased AOPP and UA levels. RA was best predicted by increased NOx/TRAP ratio, CRP, and BMI. In conclusion, our data demonstrated that NOx and NOx/TRAP are strongly associated with RA physiopathology. Our findings suggest that inhibition of iNOS may become an interesting therapeutic approach for the treatment of RA. In addition, the presence of MetS and a decrease in levels of UA by leflunomide favor redox imbalance in RA patients. More studies are needed to evaluate the impact of antioxidant capacity reduction on RA progression

Cytokines in systemic lupus erythematosus: Far beyond Th1/Th2 dualism lupus: Cytokine profiles

The aims of this study were to delineate cytokine profiles of systemic lupus erythematosus (SLE), construct prediction models for diagnosis and disease activity using those profiles, and to examine the associations between TNFB Ncol polymorphism, body mass index (BMI) and Vitamin D levels with cytokine levels. Two hundred SLE patients and 196 healthy controls participated in this case-control study. Plasma cytokines levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ 3, interleukin (IL)-1β, IL- 4, IL-6, IL-10, IL-12 and IL-17 were measured and cytokines profiles were computed. IL-6, IL-12, IL-17, IFN-γ 3 and IL-10 levels were significantly higher in SLE, while IL-4 was lower in SLE. The Th1/Th2 and Th1+Th17/Th2 profiles were significantly higher in SLE than in healthy controls, whereas there were no significant differences in the proinflammatory cytokine profile (TNFα+IL-6+IL-1β). In total, 90.4% of all subjects were correctly classified using Th1+Th17 profile and IL-10 (positively associated) and IL-4 (negatively associated) as predictor variables (sensitivity=66.7% and specificity=96.9%). In all, 20.9% of the variance in the SLE Disease Activity Index was predicted by the Th1+Th17/Th2 ratio, IL-10 and BMI (all positively) and proinflammatory profile (inversely associated). B1/B1 genotype is accompanied by increased IL-17 and Th17/Th2 ratio, while B1/B2 genotype is accompanied by higher IL-4 and IFNγ 3 values. 25-OH Vitamin D was inversely associated with IFN-γ 3 levels. SLE is accompanied by Th1, Th17 and Treg profile and lowered IL-4 production. Lowered Vitamin D levels and B1/B1 genotype, but not BMI, contribute to changes in cytokines profiles. Future treatments should target Th1, Th2 and Th17 profiles rather than inflammatory cytokines