Dipolar resonances in conductive carbon micro-fibers probed by near-field terahertz spectroscopy

We observe dipole resonances in thin conductive carbon micro-fibers by detecting an enhanced electric field in the near-field of a single fiber at terahertz (THz) frequencies. Time-domain analysis of the electric field shows that each fiber sustains resonant current oscillations at the frequency defined by the fiber's length. Strong dependence of the observed resonance frequency and degree of field enhancement on the fibers' conductive properties enable direct non-contact probing of the THz conductivity in single carbon micro-fibers. We find the conductivity of the fibers to be within the range of 1– 5×104 S/m. This approach is suitable for experimental characterization of individual doped semiconductor resonators for THz metamaterials and devices

High-definition electrocardiography potential in identifying the reasons for unstable clinical course of coronary heart disease

Aim: To investigate the correlation between clinical and morphological characteristics of coronary heart disease (CHD) and high-definition electrocardiography (HD-ECG) parameters. Material and methods: In total, 85 patients with unstable angina and ST segment depression (ST-UA) underwent HD-ECG during the angina attack, with late ventricular potential (LVP) analysis. One-year survival data were also analysed. Post-mortem histological examination of cardiac tissue was performed in 6 patients with ST-UA. Results: The important morphologic features of ST-UA included cardiomyocyte (CMC) dystrophy, due to acute and chronic myocardial ischemia, and acute injury in the cardiac conduction areas. LVPs were registered in 27 % of the ST-UA patients, mostly among people with transient myocardial ischemia (69,57 %). In patients who previously underwent myocardial infarction, LVP prevalence was lower (28,57 %). At the early stages of hospitalization, LVP were registered in 14 patients (60,87 %), while pharmacotherapy and clinical course stabilization were associated with decreased LVP prevalence (21,74 %). The study results suggest that in patients with acute coronary syndrome, LVP registration predicts not an adverse outcome, but a better prognosis. Conclusion: ST-UA is characterised by typical changes of CMC and myocardial stroma in posterior septal area, which result in metabolic, energetic, and electrical myocardial instability. LVPs could be used as a marker of functional (ischemic) myocardial heterogeneity in patients with ST-UA. LVP registration could be associated with a better prognosis in this clinical group

The direction of the breeding process in a herd of Ayrshire breed cows in the conditions of the Vologda region

The direction of the breeding process in herds and populations of dairy cattle breeds based on the actual indicators and variability of the trait is one of the main factors that allows to determine the effectiveness of breeding measures. As the initial material for the research there were taken the data of breeding records (n=681) of Ayrshire breed cows of the agricultural complex "Maysky" of the Vologda region. The number of cows was distributed by generations (195 cows with the first incomplete lactation, 177 cows with the first completed lactation, 130 cows for the second lactation, 179 cows for the third lactation and older). According to the research results, the superiority of the actual indicators for the live weight of heifers in animals of modern generation in early age periods was from 28 to 39 kg. Consequently, with each new generation, animals have better development indicators, as evidenced by the indicators of variation (variability) of the live weight of heifers in the early age periods of weak and moderate Cv = 5.3 to 10.6 %, depending on generation. The reduction of the age of the first insemination of heifers to 13.4 months (-2.2 months) and the first fruitful insemination to 14.0 months (-2.1 months) in animals from full-age to the first incomplete lactation was revealed. A targeted selection of cows was carried out in the herd according to the level of milk productivity of mothers after the first lactation - the selection efficiency was 977 kg of milk, according to the highest - 456 kg. The selection of breeding bulls was carried out according to the level of productivity of the breeding stock, however, it should be noted that the intensity of selection in cows for the incomplete first (10968 kg of milk) and first lactation (10635 kg of milk) is reduced compared to cows for the second lactation (11417 kg of milk). Consequently, in herds and populations of dairy cattle breeds, in order to achieve genetic progress in productivity in the next generation, it is necessary to determine the direction of the breeding process

Hypersensitivity reactions, hepatotoxicity, and other discontinuations in persons receiving integrase strand transfer inhibitors: results from the EuroSIDA study

Background: Hypersensitivity reaction (HSR) and hepatotoxicity are rare, but potentially serious side-effects of antiretroviral use. / Objective: To investigate discontinuations due to HSR, hepatotoxicity or other reasons among users of dolutegravir (DTG) vs. raltegravir (RAL) or elvitegravir (EVG) in the EuroSIDA cohort. / Methods: We compared individuals ≥18 years and starting combination antiretroviral therapy (ART, ≥3 drugs) with DTG vs. RAL or EVG, with or without abacavir (ABC), between January 16, 2014 and January 23, 2019. Discontinuations due to serious adverse events (SAEs) were independently reviewed. / Results: Altogether 4366 individuals started 5116 ART regimens including DTG, RAL, or EVG, contributing 9180 person-years of follow-up (PYFU), with median follow-up 1.6 (interquartile range 0.7-2.8) years per treatment episode. Of these, 3074 (60.1%) used DTG (1738 with ABC, 1336 without) and 2042 (39.9%) RAL or EVG (286 with ABC, 1756 without). 1261 (24.6%) INSTI episodes were discontinued, 649 of the DTG-containing regimens (discontinuation rate 115, 95% CI 106-124/1000 PYFU) and 612 RAL or EVG-containing regimens (173, CI 160-188/1000 PYFU). After independent review, there were five HSR discontinuations, two for DTG (one with and one without ABC, discontinuation rate 0.35, CI 0.04-1.28/1000 PYFU), and three for RAL or EVG without ABC (0.85, CI 0.18-2.48/1000 PYFU). There was one hepatotoxicity discontinuation on DTG with ABC (discontinuation rate 0.18, CI 0.00-0.99/1000 PYFU). / Conclusion: During 5 years of observations in the EuroSIDA cohort independently reviewed discontinuations due to HSR or hepatotoxicity were very rare, indicating a low rate of SAEs

Viral Load in COVID-19: Underestimated Clinical and Epidemiological Marker

Background. The viral load of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of the new coronavirus infection, is becoming increasingly important in clinical and epidemiological contexts. Despite this, there are significant complexities in the implementation of viral load quantitative measurement into clinical practice due to the limited approaches to its assessment.The aim of this work was to develop an approach for SARS-CoV-2 viral load analysis by the value of sample threshold cycles (Ct) relative to the Ct of the internal control sample obtained in routine PCR diagnostics of the COVID-19, and to use this approach for quantitative monitoring of viral load in patients with first positive SARS-CoV-2 test from the Irkutsk region.Materials and methods. Using regression models based on the least squares method, an approach to determine the number of copies of SARS-CoV-2 RNA in 1 ml of nasopharyngeal secretion was developed. The viral load of SARS-CoV-2 was assessed in nasopharyngeal and pharyngeal samples obtained from 1370 patients from Irkutsk and Angarsk with primary diagnosed positive PCR result in the period from July 1 to November 10, 2020.Results. A tenfold increase in the average monthly viral load among patients in September-October 2020 was revealed. We assume that the change in the epidemiological pattern of the spread of the new coronavirus infection during this period is associated with an increase in the number of contacts in the population due to the school year beginning. Higher viral loads are observed in populations at risk for COVID-19 – among healthcare workers and adults/elderly patients. Conclusion. The development of a standardized quantification of SARS-CoV-2 viral load in the nasopharyngeal samples can be a predictive clinical marker and a reliable tool for improving COVID-19 surveillance using the proposed approach to assess average viral load in a local population

Disparities in HIV clinic care across Europe: findings from the EuroSIDA clinic survey

BACKGROUND: Although advances in HIV medicine have yielded increasingly better treatment outcomes in recent years, HIV-positive people with access to antiretroviral therapy (ART) still face complex health challenges. The EuroSIDA Study Group surveyed its clinics to explore regional differences in clinic services. METHODS: The EuroSIDA study is a prospective observational cohort study that began enrolling patients in 1994. In early 2014, we conducted a 59-item survey of the 98 then-active EuroSIDA clinics. The survey covered HIV clinical care and other aspects of patient care. The EuroSIDA East Europe study region (Belarus, Estonia, Lithuania, the Russian Federation and Ukraine) was compared to a “non-East Europe” study region comprised of all other EuroSIDA countries. RESULTS: A larger proportion of clinics in the East Europe group reported deferring ART in asymptomatic patients until the CD4 cell count dropped below 350 cells/mm3 (75 % versus 25 %, p = 0.0032). Considerably smaller proportions of East Europe clinics reported that resistance testing was provided before ART initiation (17 % versus 86 %, p < 0.0001) and that it was provided upon treatment failure (58 % versus 90 %, p = 0.0040). Only 33 % of East Europe clinics reported providing hepatitis B vaccination, compared to 88 % of other clinics (p < 0.0001). Only 50 % of East Europe clinics reported having access to direct-acting antivirals for hepatitis C treatment, compared to 89 % of other clinics (p = 0.0036). There was significantly less tuberculosis/HIV treatment integration in the East Europe group (27 % versus 84 % p < 0.0001) as well as significantly less screening for cardiovascular disease (58 % versus 90 %, p = 0.014); tobacco use (50 % versus 93 %, p < 0.0001); alcohol consumption (50 % versus 93 %, p < 0.0001); and drug use (58 % versus 87 %, p = 0.029). CONCLUSIONS: Study findings demonstrate how specific features of HIV clinics differ across Europe. Significantly more East Europe clinics deferred ART in asymptomatic patients for longer, and significantly fewer East Europe clinics provided resistance testing before initiating ART or upon ART failure. The East Europe group of clinics also differed in regard to hepatitis B vaccination, direct-acting antiviral access, tuberculosis/HIV treatment integration and screening for other health issues. There is a need for further research to guide setting-specific decision-making regarding the optimal array of services at HIV clinics in Europe and worldwide

Online service for interpretation of the resistance prediction results to bedaquiline by the molecular data

Background. Bedaquiline is a new and promising anti-tuberculosis drug, but longterm use requires resistance. This is due to mutations in the atpE and mmpR genes in M. tuberculosis (MBT).The aim of the research was to test a system for automated interpretation of results for predicting resistance to bedaquiline by the molecular data.Materials and methods. DNA was isolated from strains of M. tuberculosis in the Irkutsk region and Yakutia. The total quantity of DNA samples was 27 strains from Yakutia and 21 strains from the Irkutsk region. The study of MBT genomes was carried out on the DNA previously obtained by the authors in the territories of the Irkutsk region (n = 5), Yakutia (n = 4), Buryatia (n = 3), Zabaykalskiy kray (n = 4) and the Far East (n = 8). We used the BSATool program to detect bedaquiline resistance based on  Sanger and genomic data. Sanger sequencing analyzed the atpE and  mmpR genes, and whole genome sequencing examined mutations in the same sequences, as well as additionally in mmpL5, mmpS5, Rv0678, Rv1979c, and pepQ.Results. Complete agreement between the phenotypic and genotypic analysis of resistance to bedaquiline was found for three strains from Yakutia. One genome with significant mutations to bedaquiline was identified. A conclusion was made about the importance of molecular analysis of target genes with subsequent detection of resistance to bedaquiline in silico

Prevalence and outcomes of pregnancies in women living with HIV over a 20-year period: The EuroSIDA study, 1996 to 2015

OBJECTIVE: To evaluate time trends in pregnancies and pregnancy outcomes among women living with HIV in Europe. DESIGN: European multicentre prospective cohort study. METHODS: EuroSIDA has collected annual cross-sectional audits of pregnancies between 1996 and 2015. Pregnancy data were extracted and described. Odds of pregnancy were modelled, adjusting for potential confounders using logistic regression with generalised estimating equations. RESULTS: Of 5535 women aged 16 to <50 years, 4217 (76.2%) had pregnancy information available, and 912 (21.6%) reported 1315 pregnancies. The proportions with at least one pregnancy were 28.1% (321/1143) in East, 24.5% (146/596) in North, 19.8% (140/706) in West/Central, 19.3% (110/569) in Central East and 16.2% (195/1203) in South Europe. Overall 319 pregnancies (24.3%) occurred in 1996-2002, 576 (43.8%) in 2003-2009 and 420 (31.9%) in 2010-2015. After adjustment, the odds of pregnancy were lower in 1996-2002, in South, Central East and East compared to West/Central Europe, in older women, those with low CD4 counts or with prior AIDS, and higher in those with a previous pregnancy or who were HCV positive.Outcomes were reported for 999 pregnancies in 1996-2014, with 690 live births (69.1%), seven stillbirths (0.7%), 103 spontaneous (10.3%) and 199 medical abortions (19.9%). CONCLUSIONS: Around 20% of women in EuroSIDA reported a pregnancy, with most pregnancies after 2002, when more effective antiretroviral therapy became available. Substantial differences were seen between European regions. Further surveillance of pregnancies and outcomes among women living with HIV is warranted to ensure equal access to care

Genotypic and phenotypic characteristics of <i>Mycobacterium tuberculosis</i> drug resistance in TB children

Background. Russian Federation is included in the list of 30 countries with the highest burden of tuberculosis, including MDR tuberculosis. The most important part of this problem is the primary MDR/XDR TB in children.The aim: a comparative analysis of the phenotypic and genotypic profile of drug resistance to anti-tuberculosis drugs (ATP) according to whole genome sequencing of M. tuberculosis strains from children.Materials and methods. Whole genome sequencing (WGS) results of 61 M. tuberculosis isolates from children with tuberculosis in 2006–2020 in the Russian Federation were analyzed for anti-TB drug resistance mutations, according to the WHO catalog and were compared with the results of phenotypic drug sensitivity.Results. The M. tuberculosis belonged to two genetic groups: Beijing genotype – 82 % (50/61) dominant Central Asian Russian (31/50) and B0/W148 (16/50) subtypes, and non-Beijing (Ural, S, LAM) – 18 % (11/61). Three isolates belonged to Asian Ancestral subtype (3/50). Of the 61 isolates, only 14.7 % (9/61) were sensitive to antiTB drugs, 49.2 % (30/61) were MDR and 14.7 % (9/61) were pre-XDR. Comparison of the resistance profile (MDR/pre-XDR) with genotype revealed an upward shift for Beijing isolates, in particular Beijing B0/W148 (15/16) subline compared to other Beijing (19/34) (Chi-square with Yates correction = 5.535; p &lt; 0.05) and nonBeijing (5/12) (Chi-square with Yates correction = 6.741; p &lt; 0.05) subtypes. Discrepancies between genotypic and phenotypic drug resistance profiles were found in 11.5 % (7/61) of cases.Conclusions. Based on the analysis of WGS data, the genotypic characteristics of M. tuberculosis and the most complete set of drug resistance mutations were obtained, indicating a significant prevalence in MDR and pre-XDR TB of cases caused by epidemic subtypes of Beijing (B0/W148 and Central Asian Russian). The molecular mechanisms of adaptation of M. tuberculosis to the treatment of anti-TB drugs are not unique for the child population but reflect the general processes of the spread of MDR/XDR in Russia

Stability of Terrestrial Planets in the Habitable Zone of Gl 777 A, HD 72659, Gl 614, 47 Uma and HD 4208

We have undertaken a thorough dynamical investigation of five extrasolar planetary systems using extensive numerical experiments. The systems Gl 777 A, HD 72659, Gl 614, 47 Uma and HD 4208 were examined concerning the question of whether they could host terrestrial like planets in their habitable zones (=HZ). First we investigated the mean motion resonances between fictitious terrestrial planets and the existing gas giants in these five extrasolar systems. Then a fine grid of initial conditions for a potential terrestrial planet within the HZ was chosen for each system, from which the stability of orbits was then assessed by direct integrations over a time interval of 1 million years. The computations were carried out using a Lie-series integration method with an adaptive step size control. This integration method achieves machine precision accuracy in a highly efficient and robust way, requiring no special adjustments when the orbits have large eccentricities. The stability of orbits was examined with a determination of the Renyi entropy, estimated from recurrence plots, and with a more straight forward method based on the maximum eccentricity achieved by the planet over the 1 million year integration. Additionally, the eccentricity is an indication of the habitability of a terrestrial planet in the HZ; any value of e>0.2 produces a significant temperature difference on a planet's surface between apoapse and periapse. The results for possible stable orbits for terrestrial planets in habitable zones for the five systems are summarized as follows: for Gl 777 A nearly the entire HZ is stable, for 47 Uma, HD 72659 and HD 4208 terrestrial planets can survive for a sufficiently long time, while for Gl 614 our results exclude terrestrial planets moving in stable orbits within the HZ.Comment: 14 pages, 18 figures submitted to A&