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Purpose: The purpose of this study was to examine the impact of the first year of COVID-19 pandemic on maternal and neonatal outcomes at a large military treatment facility in Southern California. Study Design and Methods: A retrospective review of maternal and neonatal medical records was conducted between January 1, 2019, and December 31,2020. Outcomes measured included necesstillbirth rate, neonatal intensive care unit admission, neonatal death, cesarean birth, and postpartum hemorrhage. Results: A total of 4,425 records were analyzed. Rates of stillbirth between the years did not vary. The neonatal death rate decreased more than 50% in 2020 (p = .149). Cesarean births rose by 2.7% in 2020 Cp = .046) Rates of postpartum hemorrhage did not vary between years. Clinical Implications: The impact of COVID-19 on maternal and neonatal outcomes at a military treatment facility in the first year of the COVID-19 pandemic provides guidance for optimizing perinatal health care. Vertical transmission of COVID-19 is low and routine testing of asymptomatic neonates of positive mothers may not be necesstillbirth sary. COVID-19 infections should not be an indication for cesarean birth and are not associated with neonatal deaths or NICU admission. [ABSTRACT FROM AUTHOR]

Whether steady-state gaseous microgravity spherical diffusion exist in the presence of radiation heat loss is an important fundamental question and has important implications for spacecraft fire safety. In this work, experiments aboard the International Space Station and a transient numerical model are used to investigate the existence of steady-state microgravity spherical diffusion flames. Gaseous spherical diffusion flames stabilized on a porous spherical burner are employed in normal (i.e., fuel flowing into an ambient oxidizer) and inverse (i.e., oxidizer flowing into an ambient fuel) flame configurations. The fuel is ethylene and the oxidizer oxygen, both diluted with nitrogen. The flow rate of the reactant gas from the burner is held constant. It is found that steady-state gaseous microgravity spherical diffusion flames can exist in the presence of radiation heat loss, provided that the steady-state flame size is less than the flame size for radiative extinction, and the flame develops fast enough that radiation heat loss does not drop the flame temperature below the critical temperature for radiative extinction (1130 K). A simple model is provided that allows for the identification of initial conditions that can lead to steady-state spherical diffusion flames. In the spherical, infinite domain configuration, the characteristic time for the diffusion-controlled system to effectively reach steady-state is found to be on the order of 100,000 s. Despite a narrow range of attainable conditions, flames that exhibit steady-state behavior are observed aboard the ISS for up to 870 s, even with the constraint of a finite boundary. Steady-state flames are simulated using the numerical model for over 100,000 s. [ABSTRACT FROM AUTHOR]

Previous studies have found that the elevation of ambient pressure helps facilitate cool and warm flame formation. In this work, the behavior and chemical kinetics of burner-supported C 2 H 4 microgravity spherical diffusion flames at elevated pressure are examined. Experiments were carried out aboard the International Space Station at pressures of 0.5–3 bar, and thin-filament pyrometry measurements were used to measure peak flame temperature. Flame temperatures at extinction are shown to decrease with increasing pressure, and at a pressure of 3 bar the flame is shown to extend below the critical temperature of 1130 K and into the warm flame regime. Simulations were performed using a transient numerical model with detailed chemistry, transport, and radiation. This model incorporates the San Diego mechanism with 57 species and 270 reactions, including low-temperature chemistry. Species concentrations, temperatures, reaction rates, and heat release rates are examined. When the pressure is increased to 50 bar the flame smoothly transitions into the warm flame regime, and cool flame behavior is observed in the simulations after warm flame radiative extinction. The results for hot, warm, and cool flame combustion at elevated pressure are compared to the results for hot flame burning at atmospheric pressure. The flame is shown to move from stabilizing on the oxidizer side to the fuel side as temperature decreases. The HO 2 radical becomes the dominant radical early in the flame lifetime and is largely responsible for the emergence of low-temperature chemistry. [ABSTRACT FROM AUTHOR]

Infections caused by nontuberculous mycobacteria (NTM) are rising globally throughout the world. The number of species isolated from clinical samples is steadily growing, which demands the implementation of a robust diagnostic method with wide specificity. This study was carried out in in 2022-2024 in three clinical antituberculosis centers in the biggest cities of Russia: Moscow, Saint Petersburg, and Novosibirsk. We developed the DNA hybridization assay 'Myco-biochip' that allows the identification of 79 mycobacterial species and analyzed 3119 samples from 2221 patients. Sixty-eight mycobacterial species were identified in clinics, including the three novel species phylogenetically related to M. duvalii , M. lentiflavum , and M. talmoniae . The identification of a close relative of M. talmoniae adds to the existence of separate clade between M. terrae , M. triviale complexes and other slow-growing Mycobacteria , which supports the thesis against the splitting of Mycobacteria into five separate genera. Adding to the list of potentially pathogenic species, we identified M. adipatum and M. terramassiliense , which were previously described as natural habitats. The diversity of acid-fast bacilli identified in TB-suspected persons was not limited to the Mycobacteria genus and also includes species from genera Nocardia , Gordonia , Corynebacterium , Tsukamurella , and Rhodococcus of the order Mycobacteriales . The revealed bacterial diversity in patients with suspected NTM-diseases requires the implementation of relevant species identification assays as the first step in the laboratory diagnostic pipeline.

This article reviews the contemporary understanding of the functional role of connexins in intercellular communications, their involvement in maintaining cellular and tissue homeostasis, and in aging-associated respiratory disease pathogenesis. Connexins are discussed as potential therapeutic targets. The review particularly focuses on the involvement of gap junction connexins and hemichannels in the transfer of calcium ions, metabolite molecules, ATP, and mitochondria through the cell membrane. Various disorders in the regulation of intercellular communication can heavily contribute to the pathogenesis of multiple diseases, including respiratory system diseases. A deeper understanding of molecular mechanisms underlying the activities of various connexins in gap junction channels will enable the prospective development of therapeutic approaches by either inhibiting or stimulating the activities of a certain connexin, while considering its critical functions in intercellular communications on the whole.

Problems with breathing and lung function are caused by the development of various lung diseases associated with lifestyle, harmful environmental factors and genetic predisposition. Knowledge of the molecular mechanisms of the development of the pathological process will allow on time identification of the disease or the development of targeted therapy. The article provides an overview of modern methods that make it possible to most accurately reproduce the structural, functional and mechanical properties of the lung (organ-on-a-chip), to perform non-invasive molecular studies of biomarkers of bronchopulmonary pathology using saliva diagnostics, as well as using DNA and RNA aptamers, verify tumor markers in biological samples of human tissue. Analysis of alterations in the pattern of protein glycosylation using glycodiagnostic methods makes it possible to detect lung cancer in the early stages.

A 19-year-old patient after previous wedge resection of the right upper pulmonary lobe a year ago urgently admitted with recurrent right-sided spontaneous pneumothorax. According to standard management of spontaneous pneumothorax, we performed diagnostic thoracoscopy and drainage of the right pleural cavity with regular X-ray examinations. However, these measures were ineffective. The patient was scheduled for surgery, and we intraoperatively observed an unusual cause of pneumothorax. Thus, we present spontaneous pneumothorax following right upper lobe pulmonary sequestration. The uniqueness of this case is associated with unusual manifestation and non-standard localization of rare lesion. A few cases of pneumothorax in similar patients are described in the world literature. The key limiting factor in diagnosis of such defects (identification of aberrant vessel supplying abnormal lung parenchyma) is the lack of routine CT angiography in patients diagnosed with pneumothorax. That is why CT changes were interpreted as postoperative ones, and the true cause was established only during redo surgery. A thorough inspection of the pleural cavity and alertness regarding unusual appearance of the right upper pulmonary lobe made it possible to suggest a non-standard diagnosis, avoid complications (bleeding from afferent vessel) and perform adequate lung resection.

A small set of twelve compounds of a nitrofuran carboxamide chemotype was elaborated from a readily available 2,6-diazaspiro[3.4]octane building block, exploring diverse variants of the molecular periphery, including various azole substituents. The in vitro inhibitory activities of the synthesized compounds were assessed against Mycobacterium tuberculosis H37Rv. As a result, a remarkably potent antitubercular lead displaying a minimal inhibitory concentration of 0.016 μg/mL was identified.

A chemically diverse set of 13 5-nitrofuran-tagged heterocyclic compounds has been prepared via the Groebke-Blackburn-Bienaymé multicomponent reaction. The testing of these compounds against the so-called ESKAPE panel of pathogens identified an apparent lead compound- N -cyclohexyl-2-(5-nitrofuran-2-yl)imidazo[1,2- a ]pyridine-3-amine ( 4a )-which showed an excellent profile against Enterobacter cloacae, Staphylococcus aureus, Klebsiella pneumoniae, and Enterococcus faecalis (MIC 0.25, 0.06, 0.25 and 0.25 µg/mL, respectively). Its antibacterial profile and practically convenient synthesis warrant further pre-clinical development. Certain structure-activity relationships were established in the course of this study which were rationalized by the flexible docking experiments in silico. The assessment of antitubercular potential of the compounds synthesized against drug sensitive H37v strain of Mycobacterium tuberculosis revealed little potential of the imidazo-fused products of the Groebke-Blackburn-Bienaymé multicomponent reaction as chemotherapeutic agents against this pathogen.