Newborns from women infected with COVID-19: somatic and metabolic status

To date, there are limited data regarding manifestations of new coronavirus infection in infants born of SARS-CoV-2 infected mothers, so the aim of this study is to investigate somatic and metabolic status of newborn infants born to mothers diagnosed with COVID-19. The investigation was carried out on the bases of Laboratory Diagnostic Department of Samara Regional Clinical Hospital named after V.D. Seredavin and the Department of Fundamental and Clinical Biochemistry with Laboratory Diagnostics of Samara State Medical University. Under observation were 85 newborns, including 35 born of healthy mothers and 50 born of COVID-19 mothers.The somatic status of all newborns was assessed using the Apgar scale at the 1st and 5th minutes after birth. Also all newborns had general and biochemical blood tests and newborns from mothers with COVID-19 were tested for the presence of SARS-CoV-2 RNA in oral and nasopharyngeal swabs. Thus, the study of somatic status revealed that of 50 neonates from women infected with COVID-19, only 18% were practically healthy, the rest had signs of prematurity, hypotrophy, perinatal CNS damage, diabetic fetopathy, pulmonary atelectasis, delayed intrauterine development, asphyxia. The metabolic state is characterised by decreased haemoglobin and platelets, increased concentration of total protein, including C-reactive protein, high transaminase activity, decreased sodium and chloride content. These parameters of general and biochemical blood tests can be considered as indicators for the evaluation of the condition of newborns from mothers with COVID-19.

[Experience with 13-valent conjugated pneumococcal vaccine in HIV-infected patients]

AIM

Evaluate the effect of PCV13 vaccination on the composition of the microflora of the upper respiratory tract and the immune system in HIV-infected patients.

MATERIALS AND METHODS

100 patients with HIV-infection were included in the study. The patients underwent immunological examination and the collection of biomaterial from the posterior pharyngeal wall for microbiological examination. After obtaining the results of the examinations, PCV13 was intramuscularly administered. 7 days after the introduction of the vaccine, an assessment of adverse events was carried out, after 3 months, microbiological and immunological examinations were repeated.

RESULTS

Immediately after the administration of PCV13, 5% of patients felt pain during the administration. Local reactions were reported in 6 patients. One participant showed a rise in temperature to 38.3C over 2 days. Before vaccination, 16 strains of S. pneumoniae were seeded in patients. 3 months after the administration of PCV13, pneumococcus was isolated in 8 patients. 3 months after immunization, the median level of populations and subpopulations of lymphocytes became higher than the pre-vaccination.

DISCUSSION

Our results show high risk of pneumococcal infections in HIV-positive patients. A tendency towards a decrease in the level of S. pneumoniae carriage was revealed 3 months after the administration of PCV13. The high level of enterobacteria carriage in HIV-positive patients is noteworthy. There is a pronounced positive effect from the use of PCV13 in HIV-positive patients on cellular factors of the immune system.

CONCLUSION

The use of PCV13 is a safe and effective method for the prevention of S. pneumoniae infections.

DETECTION OF ADENOVIRUS ANTIGEN BY A SURFACE-ENHANCED RAMAN SCATTERING ENZYME-LINKED IMMUNOSORBENT ASSAY

Aim. Study of the possibility of adenovirus antigen detection by recording of surface-enhanced Raman scattering (SERS) spectra of enzyme oxidized product of 3,3',5,5'-tetramethylbenzidine. Materials and methods. Clinical fecal samples containing adenoviruses, group A rotaviruses, noroviruses and healthy children samples, as well as laboratory strains of adenoviruses with a titer of 5 — 6 lg TCD50/ml were used. Sandwich immunoassay was used, the Raman spectra were recorded by a Raman spectrometer (532 nm) after incubation with silver nanoparticles. Results. The concordance of the adenovirus detection results was obtained in comparison with the enzyme immunoassay method with colorimetric detection and PCR. Conclusion. The possibility of TMB+ using as a SERS reporter and silver nanoparticles as a SERS substrate for the detection of adenovirus antigen in complex biological samples was shown.

[The difficulties of cytologic diagnostic of breast diseases based on trepanobiopsy samples.]

The article analyses, on the basis of scientific publications and original data, the causes of erroneous cytological conclusion concerning samples of trepanobiopsies of mammary gland. The most prevalent benign affections that are characterized by most frequent hyper diagnostic of cancer are fibro-adenoma with proliferation of epithelium and sclerosing adenosis. At the same time, certain modifications of lobular carcinoma of mammary gland, tubular, papillary cancer as well as highly differentiated invasive carcinoma of nonspecific type from cells with ulterior nuclear atypism sometimes it is difficult to diagnose at the cellular level. The sensitivity of cytological diagnostic of pathology of mammary gland using samples of trepanobiopsies makes up 97.5%, specificity - 98.5%. The number of false positive cytological conclusions about presence of malignant tumor makes up to 0.6%, false negative - 1.5%. The reliability of cytological analysis makes up to 97.4%, efficiency - 96.3%.

[THE TECHNOLOGY "CELL BLOCK" IN CYTOLOGICAL PRACTICE]

The article presents summary information concerning application of "cell block" technology in cytological practice. The possibilities of implementation of various modern techniques (immune cytochemnical analysis. FISH, CISH, polymerase chain reaction) with application of "cell block" method are demonstrated. The original results of study of "cell block" technology made with gelatin, AgarCyto and Shadon Cyoblock set are presented. The diagnostic effectiveness of "cell block" technology and common cytological smear and also immune cytochemical analysis on samples of "cell block" technology and fluid cytology were compared. Actually application of "cell block" technology is necessary for ensuring preservation of cell elements for subsequent immune cytochemical and molecular genetic analysis.

pH- and Electro-Responsive Properties of Poly(acrylic acid) and Poly(acrylic acid)-block-poly(acrylic acid-grad-styrene) Brushes Studied by Quartz Crystal Microbalance with Dissipation Monitoring

We report on the synthesis of novel pH- and electro-responsive polyelectrolyte brushes from a gold substrate by direct one-step nitroxide-mediated polymerization of acrylic acid (AA) or copolymerization of AA and styrene (S). In the latter case, amphiphilic brushes of block-gradient copolymers PAA-b-(PAA-grad-PS) comprising one PAA block and one block with the gradient sequence of AA and S were obtained. The block-gradient copolymers are initiated from the surface by the start of the PAA block. The brushes were characterized by XPS and ellipsometry. (1)H NMR confirmed the gradient sequence of the PAA-grad-PS copolymer block. The pH- and electro-responsive properties of the brushes were studied by quartz crystal microbalance with dissipation monitoring (QCM-D) in combination with electrochemistry. This method provides evidence of swelling of the PAA brushes proportional to the contour length of the chains at elevated pH, whereas the response functions of the block-gradient copolymers are more complex and point to intermolecular aggregation in the brush at low pH. Monitoring of the changes in resonance frequency and dissipation of the QCM-D also demonstrates that application of negative voltage to the substrate leads to swelling of the brush; application of a positive voltage provokes only a transient collapse of the brush in proportion to the applied voltage.

[Heterogeneity of hepatitis B virus and diagnostic potential of modern test systems for the detection of HBsAg]

AIM

Study heterogeneity ofhepatitis B virus in adult patients with chronic hepatitis B and determination of diagnostic potential of modern test systems with the detection of HBsAg with amino acid substitutions in the main hydrophilic region (MHR).

MATERIALS AND METHODS

In 27 hepatitis B virus samples isolated from patients with chronic hepatitis B virus infection living in Vladimir, nucleotide sequence ofgenome region corresponding to preS1/preS2/S genes was determined.

RESULTS

In all of the 27 isolates genotype D virus presented by 3 subgenotypes D1, D2, D3 was detected in 18%, 26% and 56% respectively. Based on the distribution of nucleotide substitutions in the compared functional regions of hepatitis B virus (virus entry into the cell coding site (2875 - 2991 n.b.), pre-S2/S promoter region (2994 - 3171 n.b.), 5'-end pre-S2 and S-genes sequences (3172 - 154 n.b. and 155-455 n.b.), MHR (455 - 635 n.b.) and 3'-end S-gene sequence (636 - 835 n.b.), substitutions are mostly concentrated in the promoter region of the S2/S-genes (30.8%). HBsAg serotypes were determined in 24 of 27 cases by using the predicted amino acid sequence, and in 17 cases HBsAg belonged to ayw2 (71%) serotype and in 7 cases - to ayw3 serotype (29%). Amino acid substitutions G145A, M133I, S132T localized in the main hydrophilic region and P217L, S207N, V184A localized in the C-end of the protein C that are connected with diagnostic and vaccine escape were identified in 5 isolates.

CONCLUSION

Diagnostic potential of test systems with the detection of HBsAg with known amino acid sequence of the MHR region were studied. Approximately equal potential of 6 test systems to detect HBsAg with amino acid substitutions G145A, M133I and S132T localized in the MHR region were shown.

[The fluorescent hybridization in situ as applied in diagnostics of urinary bladder cancer]

The adaptation of techniques of molecular genetic analysis into clinical practice increased the possibilities of diagnostics of urinary bladder cancer at early stage of disease development. The article discusses the results of cytological and cytogenetic examination of urine cells in patients with diagnostics of urinary bladder cancer. The sampling consisted of 44 cytological and 25 cytogenetic tests. The results of both methods of diagnostics of urinary bladder cancer matched in 12 cases. Besides, in 2 tests the carcinoma of urinary bladder was confirmed only by using molecular genetic technique.

[Current possibilities of cytological assay in the study of pleural and peritoneal exudates]

Serous exudates were studied by immunoperoxidase and immunofluorescence immunocytochemical assays and by laser flow cytofluorimetry. The current high-tech techniques detect sparse tumor complexes in the exudates at the early metastatic stages, which are undetectable by the routine cytological assay, and also reduce the hyperdiagnosis of the tumor process. The use of a set of immunocytochemical markers can specify the source of metastatic spread when the primary tumor focus is not found. Fluorescence immunocytochemistry of the exudates has been shown to be highly effective and rapid during emergency intraoperative studies to clarify the extent of the tumor process.

[Evaluation of the system for controlling the quality of the HBsAg detection in the system of screening laboratories]

The two-stage control system, ensuring the high quality of serological investigations in the network of screening laboratories in Moscow was developed and introduced into practice. At the first stage the entry control of the quality of the test system for the detection of HbsAg, coming to the screening laboratories, is made in the reference laboratory with the use of specially developed "representative" panels, as well as the test systems for comparison ("reference" test systems). Then "minipanels" are formed from specimens included into the "representative" panels, which are used for the evaluation of the quality of laboratory investigations made in the screening laboratories. The high quality of such system for controlling the quality of the detection of HBsAg in the screening laboratories of Moscow is shown.

[Propagation of hepatitis E virus in an endemic and nonendemic regions]

The role of hepatitis E (HE) in sporadic morbidity at an endemic territory (Southern Uzbekistan) and the incidence of anti-HEV in different populations of a nonendemic region (Russia) were evaluated. Antibodies to HEV were detected in 22.1% of patients with acute HE, including mixed infections (+ HA or HB), in the Dekhkanabad district of Kashkadarya region in 1993. The estimated incidence of acute HE was 51.7 per 100,000 population. Analysis of monthly incidence of acute HE demonstrated a seasonal pattern of the morbidity: more than 80% of total recorded cases occurred in August-September. These data indicate the presence of group HEV infections and an important role of this infection in the structure of acute viral hepatitis at the endemic territory. Anti-HEV were found in some population groups at a nonendemic territory: in free-of-charge blood donors in Surgut (4%), in patients with HIV infection (1.6%), and in medical workers in Moscow (1.1%).

[The use of plasmapheresis in treating recurrent aphthous stomatitis]

Plasmapheresis was used in multiple-modality treatment of 33 patients with chronic relapsing aphthous stomatitis. Plasmapheresis was administered on an inpatient basis in an intermittent mode with exfusion of up to 1 liter of plasma per session, 1-3 sessions per course. The efficacy of treatment was assessed from the time course of clinical picture, time of onset of remission and its duration, and metabolic and immunity parameters. Plasmapheresis improved the general status of the patients, accelerated epithelialization of the buccal mucosa, helped attain prolonged remissions, and ameliorated the homeostasis parameters.

[Induction of a delayed cyclic AMP-sensitive sodium current in mollusk neurons by G-protein activators]

The experiments have been carried out with isolated Helix pomatia neurons by the method of two-microelectrode voltage clamping. cAMP and the activators of G-proteins, F-, GTP and Gpp (NH)p, were injected via ionophoresis into the neurons using a seven-channel microelectrode. It is found that the G-protein activators induce both input and output currents in the neurons where slow sodium current can be activated by cAMP. The input G-activated and cAMP-activated currents are similar in kinetics, voltage dependence and reverse voltage. The G- and cAMP-responses are not additive. The results obtained allow the conclusion that the G-protein activators can stimulate the slow cAMP-sensitive sodium channels.

[Frequency potentiation mechanisms of cyclic AMP-dependent responses of snail neurons]

Intracellular injection of cAMP with the help of microiontophoresis (5-40 nA, 1-10 s) into land snail neurons induces rapid membrane depolarization. Action potentials have not influence on the following cAMP-responses. When the intervals between cAMP-injections are less than 5 minutes the effect of frequency potentiation of cAMP-responses is obtained. The experiments with cAMP-injection from two different barrels of multibarreled microelectrode show that a change of the microelectrode barrels during repetitive injections causes an abolition of the frequency potentiation effect of cAMP-responses. The results suggest that the frequency potentiation effect of cAMP-responses may be explained by peculiarities of microiontophoresis.

[In vitro immunization of human lymphocytes with Epstein-Barr virus capsid antigen]

Conditions for in vitro immunization of human lymphocytes from adult peripheral blood, tonsils and cord blood with Epstein-Barr Virus (EBV) capsid antigens have been studied. Pokeweed mitogen and B cell growth factor from Namalva cell line were shown to induce a significant production of specific antibodies by human lymphocytes stimulated with EBV. This effect made it possible to generate primary immune response in vitro using lymphocytes from EBV seronegative donors.

Cyclic adenosine monophosphate (cAMP)-induced potentiation of synaptic responses in Helix neurons

1. The effect of intracellularly injected cAMP on the amplitude of excitatory postsynaptic potentials was studied using identified neurons of the snail Helix pomatia. 2. In 25% of the experiments, postsynaptic cAMP elevation caused a pronounced augmentation of the excitatory postsynaptic potential (EPSP) amplitude, lasting up to 15-30 min. 3. The results suggest that a cAMP increase in the postsynaptic neuron may be involved in the enhancement of synaptic efficiency.

[Long-term potentiation in the neurons of the edible snail]

A brief high-frequency stimulation of the anal nerve of the isolated nerve ring of snail Helix induced a pronounced increase in the amplitude of EPSPs, evoked in identified neurons of left parietal and visceral ganglions by low frequency (once in 5 min) stimulation of the same nerve. The amplitude of EPSP returned to the control level 30-120 min after tetanization. We called this effect long-term potentiation. A brief application of serotonin (10 microM) in the majority of neurons also induced lasting either 15-30 min or more than 2 hours facilitation of EPSP, evoked by anal nerve stimulation. Intracellular cAMP injections, being without effect on EPSP amplitude in many neurons, in certain neurons caused an increase in EPSP amplitude, lasting up to 30 min. It is suggested that the 3 factors shown to increase synaptic efficiency in molluscan neurons may have common mechanisms of action.

[The role of cAMP in generating excitatory serotonin responses of neurons in the edible snail]

The neurons of the dorsal surface of snail Helix subesophageal ganglia respond similarly to the application of serotonin and the intracellular cAMP injection. These responses represent membrane depolarization. They increase in amplitude with membrane hyperpolarization and have a reverse potential between +10 and -30 mV. Presumably, these responses are associated with increased conductance for several ions. The values of the reverse potentials of serotonin and cAMP responses coincide in 7 out of 17 cells. Phosphodiesterase inhibitor theophylline caused a reversible increase in the amplitude and duration of both serotonin and cAMP responses and, used at a concentration of 1 mM, simulated them. The results obtained meet 2 out of 4 criteria demonstrating that cyclic nucleotides mediate a neurotransmitter response. It is suggested that cAMP may act as a second messenger in excitatory serotonin responses of snail Helix neurons.

[Possible functional role of the DD-domain of RNA-dependent polymerases]

An attempt to study the functional role of one of the most conservative domains found in all RNA-dependent RNA and DNA polymerases of plant and animal viruses (the so called "DD-domain") was made. A structure similar to the "DD-domain" was found in a minor T7 phage tail protein--gpII. Antibodies against this phage protein have been raised and used to probe "DD-domain" in molecules of avian myeloblastose virus reverse transcriptase and E. coli RNA-dependent RNA polymerase. The antibodies are shown to inhibit the activity of these enzymes under certain conditions. At the same time inhibition of the reverse transcriptase reaction causes the decrease in length of the most high molecular cDNA-products as well. The experimental data obtained are discussed in view of the suggested hypothesis on the probable functional role of the "DD-domain" of RNA-dependent polymerases.

[Atypical responses to dopamine of Helix pomatia neurons]

Atypical dopamine responses of Helix pomatia neurons accompanied by a fall in passive membrane permeability (an increase of the input resistance) were discovered. The reversal potential of the depolarizing atypical response amounted to -83 +/- 7 mV, and that of the hyperpolarizing response to -15 -20 mV. These values coincided with the reversal potentials for the hyperpolarizing and depolarizing responses to dopamine, that developed as membrane permeability increased. Biphasic dopamine responses are also described, in which the first phase is determined by an increase, while the second one with a decrease of membrane permeability. It is suggested that atypical dopamine responses are associated with specific types of ionic channels and are mediated via specific dopamine receptors.

[Translation of the genomic and subgenomic RNAs of cucumber virus 3 in a cell free system from wheat embryos and in Xenopus laevis oocytes]

The purified preparation of cucumber virus 3 (CV3) (one of the member of tobamovirus group) contains, besides full-length (2.0 X 10(6)) genomic RNA, a short (0.24 X 10(6)) subgenomic RNA coding for coat protein in Xenopus laevis oocytes as well as in the cell-free protein synthesizing system from wheat embryos. The similarity of the polypeptide coded by short CV3 RNA in vitro to natural CV3 coat protein is proved by the similarity of their molecular weights, antigenic specificity and by the similarity of the peptide maps. Individual CV3 genomic RNA coded in vitro for polypeptide 130 X 10(3), and was incapable of coding for the coat protein. The results of translation of an artificial mixture of short and full-length RNAs suggest that it is the short RNA that is preferentially translated.