Povidone-iodine functionalized nanofibers are prophylactic and protect against dissemination of SARS-CoV-2 infection.

The novel personal protection equipment based on a face mask equipped with a nanofiber filter functionalized with povidone iodine has been developed and tested in a clinical trial. This nanofiber filter was characterized with a low flow resistance and, thus, allowed comfortable breathing. The performed study proved that the novel nanofiber filter with incorporated povidone-iodine was characterized with a slow release of iodine which minimized side effects but kept disinfection efficiency. Our clinical study performed on 207 positively tested SARS-CoV-2 patients wearing the PPE for 4-8 hours daily for 1 to 4 days has shown that even the iodine amount as low as 0.00028 ppm was sufficient to significantly decrease the reproduction number and, very importantly, to protect against severe course of disease.

[Pregnant women and mothers using alcohol, tobacco and illegal drugs]. / Rodicky uzívající alkohol, tabák a nelegální drogy.

UNLABELLED: This analysis is focused on use of addictive substances among women hospitalised during delivery or puerperium. Analysed data come from National Registry of Mothers at Childbirth and from National Registry of Newborns, which are managed by the Institute of Health Information and Statistics. GOAL: To describe the prevalence of addictive substances use among women during gestation and to study its relation to health complications during pregnancy, delivery or puerperium and to health status of foetus and newborns. METHODS AND MATERIALS: The reporting to registries is provided in the Report on mother at childbirth and in the Report on newborn. Both registers provide basic socio-demographic information about mother, information about previous pregnancies and abortions, about current pregnancy, course of delivery, birth and neonatal treatment and health of newborn during hospitalization of mother during delivery or puerperium. Use of addictive substances is monitored in the National Registry of Mothers at Childbirth since 2000. Addictive substances are divided to tobacco, alcohol and drugs. Descriptive analysis of data was performed and binary logistic regression was used to test association of substance use with education and marital status (adjusted for age), analysis of variance was used to test association of substance use with selected health complications of pregnancy, delivery or puerperium and with health status of foetus/newborns (adjusted for age, education, marital status and interaction between addictive substances). RESULTS: In 2000-2009, 1,008,821 mothers were reported of whom 60,502 women were registered as cigarette smokers, 1,528 used alcohol and 1,836 used other (illegal) drugs. Total of 1,027,200 newborns were reported. The average age of mothers using addictive substances were about 0.5-3 years lower in comparison with nonusers, in average mothers using illegal drugs were the youngest. Mothers using addictive substances were more often unmarried and had lower education than nonusers - almost 2/3 of mothers using addictive substances were unmarried or didn't live in permanent partnership and more than 82% of mothers-users have lower education (primary or secondary school without a diploma). The association between substance use and induced and spontaneous abortions was observed only in smokers. Serious complications of pregnancy were associated with all monitored addictive substances - in mothers-smokers, a probability of serious complications were about 40 %, in users of illicit drugs about 13 % and in alcohol users about 5 % higher as compared to nonusers. Substance use showed almost no association with problems during childbirth. Alcohol and illegal drugs use increased probability of complications in puerperium. Health status of foetus/newborn was negatively significantly altered mainly in those born to mothers-smokers in almost all observed characteristics. Mothers alcohol use during pregnancy was associated primarily with the overall health status of foetus immediately after delivery, congenital anomalies, stillbirth or need for treatment of newborn in the theatre. Infants of mothers using addictive substances had higher probability of consequent hospitalization after discharge from the neonatal department, transfer to infant home and death of infant. CONCLUSION: Association between complications during pregnancy, delivery and puerperium and health status of newborns and substance use of mothers during pregnancy was found mainly in cigarette smoking. Alcohol use was found significant in some (but serious) health problems of mothers and newborns. The association between illegal drugs and monitored indicators wasn't found. Following the results of this work, criteria for reporting of illegal drug use in mothers during pregnancy should be improved.

Myofibrillar creatine kinase activity inferred from a 3D model.

Myofibrillar creatine kinase (CK) that buffers ATP during fluctuating muscle energy metabolism has been selected for studies of conformational changes underlying the cellular control of enzyme activity. The force field was computed for three energetic states, namely for the substrate-free CK molecule, for the molecule conjugated with the MgATP complex, and for the molecule conjugated with the pair of reactants MgATP-creatine. Without its substrates, the enzyme molecule assumes an inactive "open" form. Upon binding of the MgATP complex, the CK molecule takes up a reactive "closed" conformation. Subsequent binding of creatine yields a nonreactive "intermediary" conformation. Acid-base catalysis is considered to be the basic principle for the reversible transfer of the phosphoryl group between the substrates. The results indicate that the substrate-induced energy minimizing conformational changes do not represent a sufficient condition for CK activity and that some other essential component of physiological control at the cellular level is involved in the transition from the intermediary to the closed structure of the molecule.

Evaluation of comparative cytochrome P450 2B4 model by photoaffinity labeling.

A homology model of rabbit CYP 2B4 was constructed on the basis of the crystallographic structure of truncated mammalian CYP 2C5/3 and bacterial soluble CYPs. To validate the CYP 2B4 homology model photoaffinity labeling was employed. Three probes (I-III) containing a photo-labile azido-group and an amino-group on opposite ends of the molecule were designed for photoaffinity labeling of the CYP 2B4 in increasing distance from the heme iron. Spectroscopic data proved probes I (the shortest) and II (a middle sized) to be coordinated with the heme iron via their amino-groups in the enzyme active center while the probe III (the longest) was not bound in this way. This binding orientation of probes I and II is in accordance with the model predicting ion-pairing of the negatively charged side chain of CYP 2B4 Asp 105 and a positively charged nitrogen located in an appropriate position in structures of probes I and II, only. The lack of heme binding of the probe III is clear from its docking into the CYP 2B4 model since no Asp 105 ion-pairing is possible. The target of photoactivated probe II, Arg 197, in a distance of about 16.5 A from the heme iron, exactly matches the position of that amino acid residue, predicted from the CYP 2B4 homology model. Moreover, using this technique, a substrate access channel has been identified. To assess the predicted substrate-binding pocket, an interaction of a specific CYP 2B4 substrate, diamantane, was examined. In "silico" docking revealed strong binding of diamantane in an orientation allowing experimentally observed C4-hydroxylation. Our homology model of CYP 2B4 is thus consistent with experimental metabolic and photoaffinity labeling data.

High-resolution imaging of biological and other objects with an X-ray digital camera.

A high-resolution CCD X-ray camera based on YAG:Ce or LuAG:Ce thin scintillators is presented. The high resolution in low energy X-ray radiation is quantified with several test objects. The achieved spatial resolution of the images is <1 microm. The objects used for imaging are grids and small animals with parts of several microns in extent. The high-resolution imaging system can be used with different types of ionizing radiation (X-ray, electron, UV, and VUV) and for non-destructive micro-radiography and synchrotron beam inspection.