Widespread adaptive introgression of MHC genes across vertebrate hybrid zones.

Interspecific introgression is a potentially important source of novel variation of adaptive significance. Although multiple cases of adaptive introgression are well documented, broader generalizations about its targets and mechanisms are lacking. Multi-allelic balancing selection, particularly when acting through rare allele advantage, is an evolutionary mechanism expected to favor adaptive introgression. This is because introgressed alleles are likely to confer an immediate selective advantage, facilitating their establishment in the recipient species even in the face of strong genomic barriers to introgression. Vertebrate Major Histocompatibility Complex (MHC) genes are well-established targets of long-term multi-allelic balancing selection, so widespread adaptive MHC introgression is expected. Here we evaluate this hypothesis using data from 29 hybrid zones formed by fish, amphibians, squamates, turtles, birds and mammals at advanced stages of speciation. The key prediction of more extensive MHC introgression compared to genome-wide introgression was tested with three complementary statistical approaches. We found evidence for widespread adaptive introgression of MHC genes, providing a link between the process of adaptive introgression and an underlying mechanism. Our work identifies MHC introgression as a general mechanism by which species can acquire novel, and possibly regain previously lost, variation that may enhance defense against pathogens and increase adaptive potential.

[Organization of maxillofacial and dental care for the wounded of the Voronezh front (July 1942 - July 1943)]. / Organizatsiya chelyustno-litsevoi i stomatologicheskoi pomoshchi ranenym Voronezhskogo fronta (iyul' 1942 g. ­ iyul' 1943 g.).

The article is devoted to the history of the formation of the system of assistance to maxillofacial wounded soldiers of the Voronezh Front during the battles for Voronezh in 1942-1943. The difficulties and achievements in the implementation of phased assistance to the wounded in the face, as well as the improvement of the organizational structure of surgical and dental care for soldiers and officers of the front are reflected.

[

MicroRNAs epigenetically regulate physiological and pathological processes. Previously, we found that miR-204-5p is expressed at low levels in melanoma cells, and an increase in its level leads to a change in proliferation, migration, and invasion of these cancer cells. Now, using bioinformatics analysis, it has been shown that the target of miR-204-5p is FOXC1 transcription factor, which is implicated in carcinogenesis. Using the luciferase reporter assay, it was found that miR-204-5p suppresses expression of the FOXC1 gene by binding to its 3' non-coding region. Transfection of small interfering RNA (siRNA) targeting FOXC1 into melanoma cells caused a decrease in miR-204-5p levels, which is consistent with the generally accepted concept of feedback regulation of miRNA expression by target genes. According to the results of the MTT test and fluorescence microscopy, the proliferation level of melanoma cells under the influence of siRNA to FOXC1 decreased 72 h after transfection. Changes in the ratio of cells by cell cycle phase were analyzed using flow cytometry. Regulatory relationships between FOXC1 and miR-204-5p, and an inhibitory effect of FOXC1 knockdown on melanoma cell proliferation were revealed. Based on the results, it can be assumed that miR-204-5p regulates proliferation of melanoma cells by affecting FOXC1 expression.

Coelenterazine-dependent luciferases.

Bioluminescence is a widespread natural phenomenon. Luminous organisms are found among bacteria, fungi, protozoa, coelenterates, worms, molluscs, insects, and fish. Studies on bioluminescent systems of various organisms have revealed an interesting feature - the mechanisms underlying visible light emission are considerably different in representatives of different taxa despite the same final result of this biochemical process. Among the several substrates of bioluminescent reactions identified in marine luminous organisms, the most commonly used are imidazopyrazinone derivatives such as coelenterazine and Cypridina luciferin. Although the substrate used is the same, bioluminescent proteins that catalyze light emitting reactions in taxonomically remote luminous organisms do not show similarity either in amino acid sequences or in spatial structures. In this review, we consider luciferases of various luminous organisms that use coelenterazine or Cypridina luciferin as a substrate, as well as modifications of these proteins that improve their physicochemical and bioluminescent properties and therefore their applicability in bioluminescence imaging in vivo.

THE ANALYSIS OF MAJOR RISK FACTORS OF CARDIOVASCULAR DISEASES AMONG INHABITANTS OF THE NORTH REGION.

Last years the problem of organism's adaptation to severe climate-environmental conditions of the Far North has been intensively developed. The Republic of Sakha (Yakutia) is the most northern republic of the Russian Federation. People have created a unique way of life, language, original culture on this cold part of the earth and have carried centuries later. This unique experience has been saved up throughout many centuries and generated in natural environment of habitation and passed from generation to generation. Last years the changes of living conditions of indigenous population, urbanization and globalisation, deterioration of ecological conditions exhausted reserve possibilities of organism. Among the indigenous population health change has menacing character, especially among the children's population. The analysis of major risk factors of the development of cardiovascular diseases among the indigenous population of the north has been carried out in this research.

Relaxed functional constraints on triplicate α-globin gene in the bank vole suggest a different evolutionary history from other rodents.

Gene duplication plays an important role in the origin of evolutionary novelties, but the mechanisms responsible for the retention and functional divergence of the duplicated copy are not fully understood. The α-globin genes provide an example of a gene family with different numbers of gene duplicates among rodents. Whereas Rattus and Peromyscus each have three adult α-globin genes (HBA-T1, HBA-T2 and HBA-T3), Mus has only two copies. High rates of amino acid evolution in the independently derived HBA-T3 genes of Peromyscus and Rattus have been attributed to positive selection. Using RACE PCR, reverse transcription-PCR (RT-PCR) and RNA-seq, we show that another rodent, the bank vole Clethrionomys glareolus, possesses three transcriptionally active α-globin genes. The bank vole HBA-T3 gene is distinguished from each HBA-T1 and HBA-T2 by 20 amino acids and is transcribed 23- and 4-fold lower than HBA-T1 and HBA-T2, respectively. Polypeptides corresponding to all three genes are detected by electrophoresis, demonstrating that the translated products of HBA-T3 are present in adult erythrocytes. Patterns of codon substitution and the presence of low-frequency null alleles suggest a postduplication relaxation of purifying selection on bank vole HBA-T3.

Functional characterization of ABCC2 promoter polymorphisms and allele-specific expression.

Multidrug resistance protein 2 (MRP2, ABCC2) is an efflux membrane transporter highly expressed in liver, kidney and intestine with important physiological and pharmacological roles. The goal of this study was to investigate the functional significance of promoter region polymorphisms in ABCC2 and potential allele-specific expression. Twelve polymorphisms in the 1.6 kb region upstream of the translation start site were identified by resequencing 247 DNA samples from ethnically diverse individuals. Luciferase reporter gene assays showed that ABCC2 -24C>T both alone and as part of a common haplotype (-24C>T/-1019A>G/-1549G>A) increased promoter function 35% compared with the reference sequence (P<0.0001). No other common variants or haplotypes affected ABCC2 promoter activity. Allele-specific expression was also investigated as a mechanism to explain reported associations of the synonymous ABCC2 3972C>T variant with pharmacokinetic phenotypes. In Caucasian liver samples (n=41) heterozygous for the 3972C>T polymorphism, the 3972C allele was preferentially transcribed relative to the 3972T allele (P<0.0001). This allelic imbalance was particularly apparent in samples with haplotypes containing two or three promoter/untranslated region variants (-1549G>A, -1019A>G and -24C>T). The observed allelic imbalance was not associated with hepatic or renal ABCC2 mRNA expression. Additional mechanisms will need to be explored to account for the interindividual variation in ABCC2 expression and MRP2 function.

Selected trends in head and neck cancer epidemiology in Slovakia - an international comparison.

BACKGROUND: Head-and-neck malignant neoplasms (diagnosis group C00-C14, according to ICD-10) form a heterogeneous group of diseases with close anatomical localization. The incidence is twice to three times higher in men than in women and is increasing worldwide. OBJECTIVE: The aim of our analysis was to estimate changes of incidence and mortality rates of head-and-neck malignancies associated with anatomical topographic regions over the time as well as to compare these indicators in different selected countries of the world. Secondary endpoints included the assessment of patients' age distribution, clinical stages of newly diagnosed cases, and point prevalence of the disease in the Slovak Republic (SR). MATERIAL AND METHODS: The data base for the calculations was obtained from national databases and outputs of the National Cancer Registry (NCR) of the SR (with summary data available from the National Epidemiological Portal of Malignant Tumors, which analyzed data from 1984-2003 and was available until 2009, the remaining data were obtained from annual analyses of the NCR of the SR and the National Centre for Health Information (NCZI)), from the Statistical Office of the SR, and from the IARC WHO global database outputs on incidence, mortality, prevalence and survival of the patients. Incidence and mortality data in the SR were available up to 2012 (including) and up to 2021 (including), respectively. A log-linear joinpoint regression model was used to analyze the development of incidence and mortality rates over time by using Joinpoint Regression Program software. To achieve maximum precision in the estimated total surviving population of patients with head and neck malignant neoplasms, a model was developed to calculate the point (overall) prevalence based on absolute numbers of long-term registered national counts of newly diagnosed patients, mortality from the disease, overall mortality, and survival probability. The representation of clinical stages of head and neck carcinoma in the SR was compiled from available national data (2000-2012) and from predictions and does not consider changes in TNM classifications over the time. RESULTS: The age-adjusted (to the world standard population, ASR-W) incidence rate and the age-adjusted (ASR-W) mortality rate of head-and-neck malignant tumors in the SR have shown a significantly decreasing tendency in men since 1990; however, in women both of these indicators have shown a significant increasing tendency, especially the significantly growing incidence since 2004. In 2012, the overall age-adjusted incidence and mortality rate of head-and-neck cancers in the SR were significantly higher in males (ASR-W incidence 22.6/100,000 and ASR-W mortality 15.26/100,000) compared to females (ASR-W incidence 4.21/100,000 and ASR-W mortality 1.52/100,000). More than 75% of newly diagnosed cases are already in advanced and metastatic clinical stages, which is the most unfavourable survival factor. The absolute prevalence of these patients in the SR was estimated to be N = 9,395 in the year 2021. CONCLUSION: It is necessary to get a current and well evaluated epidemiological overviews to be able to plan preventive and intervention programs in oncology.

Discovery of regulatory elements in human ATP-binding cassette transporters through expression quantitative trait mapping.

ATP-binding cassette (ABC) membrane transporters determine the disposition of many drugs, metabolites and endogenous compounds. Coding region variation in ABC transporters is the cause of many genetic disorders, but much less is known about the genetic basis and functional outcome of ABC transporter expression level variation. We used genotype and mRNA transcript level data from human lymphoblastoid cell lines to assess population and gender differences in ABC transporter expression, and to guide the discovery of genomic regions involved in transcriptional regulation. Nineteen of 49 ABC genes were differentially expressed between individuals of African, Asian and European descent, suggesting an important influence of race on expression level of ABC transporters. Twenty-four significant associations were found between transporter transcript levels and proximally located genetic variants. Several of the associations were experimentally validated in reporter assays. Through influencing ABC expression levels, these single-nucleotide polymorphisms may affect disease susceptibility and response to drugs.

Ca(2+)-triggered coelenterazine-binding protein from Renilla as an enzyme-dependent label for binding assay.

The recombinant Ca(2+)-triggered coelenterazine-binding protein (CBP) from Renilla muelleri was investigated as a biospecifically labeled molecule for in vitro assay applications. The protein was shown to be stable in solutions in the frozen state, as well as stable under heating and to chemical modifications. Conjugates with biotin, oligonucleotide, and proteins were obtained and applied as biospecific molecules in a solid-phase microassay. CBP detection was performed with intact (no modifications were made) Renilla luciferase in the presence of calcium, and the detection limit was found to be 75 amol. Model experiments indicate that this approach shows much promise, especially with regard to the development of multianalytical systems.

[Secondary abdominal pregnancy in 19 w.g.--diagnosis and therapy].

Preserving of tubal pregnancy after first trimester is rare and very often ends fatal. Nevertheless new methods of diagnosis and therapy of ectopic pregnancy, in industrial countries it remains on first place as reason for mother mortality in first three months of pregnancy and represents 10% of all mother mortality.

[Correlation of the genetic profile and features of the rehabilitation after ischemic stroke]. / Korreliatsiia geneticheskogo profilia i osobennostei reabilitatsii posle ishemicheskogo insul'ta.

AIM: To examine an effect of polymorphisms of lipid peroxidation system genes on the risk of ischemic stroke as well as the prognosis of disease outcome after rehabilitation measures. MATERIAL AND METHODS: Seven hundred and forty-six patients with ischemic stroke and 500 patients of the control group were genotyped for 6 polymorphisms of lipid peroxidation system genes: HIF1a C1772T, ApoE Σ2/Σ3/Σ4, MnSOD C47T, GPX-1 C599T, BDNF G196T, p22phox C242T. RESULTS AND CONCLUSION: The HIF1a C1772T polymorphism was a significant risk factor for the development of ischemic stroke with the odds ratio 1.702 (p<0.05). For GPX-1 C599T and BDNF G196T polymorphisms, a trend towards a higher frequency of heterozygous genotypes was shown in patients with the negative dynamics of neurological status. The results suggest the influence of genetic variants not only on the risk of stroke but also on treatment and rehabilitation outcomes.

[Rear cases of tubal pregnancy during second trimester--diagnostic and therapeutic problems].

The lack of space abilities predetermine the fate of tubal pregnancy. Very often it disturbs in first few weeks. Preserving the tubal pregnancy after first trimester is very rear and often ends fatal. During 1970 in France the extrauterine pregnancy is met once on every 100 births. Now it is 2% from all births. In our country the relative part of ectopic pregnancy for last 20 years has grown twice. The authors represent two cases of tubal pregnancy, developed until second trimester, one of them ended fatal. The difficulties during diagnosing, characteristics of clinic and therapeutic problems are shown. Analysis are made on tendency of growing frequency of ectopic pregnancy, nevertheless modern diagnostic methods and also its role for maternal mortality.

[Peculiarities of maternal mortality in the University Hospital of Pleven for period 1977-2001].

The authors report retrospective investigation of causes for maternal mortality in the Department of Obstetric and Gynecology in Hospital in Pleven for the period 1977-2001 and comparison between indexes for a different period of time. Objects of investigation were patient histories necropsy report and forensic expertise. Vital births were 73922 for a period of 25 years in Pleven. Dead pregnant and maternity were 45 and the rate of maternal mortality was 60,07/per 100 000 vital births. Causes of maternal mortality were divided in immediate 40 cases (88,88%) and indirect--5 cases (11,11%). The hemorrhage was the most common cause of maternal mortality--18 cases (45%). The authors mention that the absolute number of maternal losses is comparatively constant but the rate of maternal mortality in creases because of tendency of decrease of birthrate and concentration of pathology in Department of Obstetric and Gynecology in Pleven.

[Calcium-regulated photoproteins of marine coelenterates].

Ca(2+)-regulated photoproteins are bioluminescent proteins responsible for bioluminescence of marine coelenterates. The photoprotein molecule is a stable enzyme-substrate complex consisting of a single polypeptide chain and an oxygen "pre-activated" substrate, 2-hydroperoxycoelenterazine, which is tightly but non-covalently bound with a protein. The bioluminescence is triggered by calcium ions and originates from an oxidative decarboxylation of a protein bound substrate. The review provides current data on the photoproteins structure, the mechanism of bioluminescent reaction, the function of some amino acid residues of an active site in the catalysis and the formation of the emitter, as well as on applications of these proteins in a bioluminescent analysis.

[Terminated pregnancy following prenatal diagnosis of congenital anomalies--a part of register of congenital anomalies].

UNLABELLED: The most of European registries of congenital anomalies (CA) collected information of CA in livebirths, stillbirths and terminated pregnancies following prenatal/ultrasound diagnosis. OBJECTIVES: to assess terminated pregnancies after prenatal/ ultrasound diagnosis of CA as a part of register of CA performed in University Hospital-Pleven. Among 21 202 births monitored during the study period (1996-2005), 679 CA were detected. The total prevalence of CA was 32/ 1000 births. The outcome of pregnancy for all cases of selected CA by register was 620 livebirths (91.3%), 36 stillbirths (5.3%), 23 terminated pregnancies (TP) (3.4%). The percentage of pregnancy termination was higher in the case of isolated anomalies, mainly lethal and CA associated with a low survival rate (61%), than with multiple ones. The most common CA detected after prenatal/ ultrasound diagnosis were neural tube defects (NTD) - the main reason for TP (52% of cases). The low proportion of these CA in TP (1/3) compared to their proportion in livebirths (50%) demonstrated an insufficiency of prenatal diagnosis of NTD as a part of register of CA performed in University Hospital-Pleven. Prenatal diagnosis of CA allows an early genetic counseling of mother presenting information on neonatal prognosis and recurrence risk for subsequent pregnancies. It helps family to take an adequate decision for termination of pregnancy with bad prognosis about heavy fetal CA.

Structural basis for the emission of violet bioluminescence from a W92F obelin mutant.

Mutation of the Trp92 that is known to lie within the active site of the photoprotein obelin from Obelia longissima, results in a shift of the bioluminescence color from blue (lambda(max)=485 nm) to violet. The corrected spectrum shows a new band with lambda(max)=410 nm now contributing equally to the one at longer wavelength. The crystal structure of this W92F obelin determined at 1.72 A resolution shows that there is no significant change in the dimensions of the active site between WT obelin (recombinant Ca2+-regulated photoprotein from Obelia longissima) and the mutant. It is proposed that the bioluminescence spectral shift results from removal of a hydrogen bond from the indole of W92 nearby a hydroxyl belonging to the 6-phenyl substituent of the substrate coelenterazine. Propagation of this change through a conjugated bond system in the excited state of the product coelenteramide affects the coupling of the N1-position and the hydrogen-bonded Y138.

Insertion of short hepatitis virus A amino acid sequences into poliovirus antigenic determinants results in viable progeny.

In an infectious poliovirus cDNA construct, the determinant encoding antigenic epitope N-Ag1 (in a loop located between two beta-strands in poly-peptide VP1) was altered by site-directed mutagenesis, to be partially similar with the determinants for presumptive epitopes in polypeptides VP1 or VP3 of hepatitis A virus (HAV). The modified constructs proved to be infectious. However, another construct, in which the same locus encoded a 'nonsense' and a relatively hydrophobic amino acid sequence, exhibited no infectivity. These data showed the feasibility of the insertion of foreign sequences in a specific antigenically active locus of the poliovirus icosahedron, and suggest some limitations with respect to the sequences to be 'transplanted'.

Variability of kidney tubular interstitial distortions in glomerulonephritis as measured by 1H-NMR urinalysis.

1H-NMR urinalysis is used for reliable non-invasive diagnostics of tubular and papillary distortions in glomerulonephritis. The study of urine from 52 patients with various clinical forms of the disease shows that these dysfunctions can manifest and develop independently of the degree of glomerular lesions at any stage of the glomerulonephritis. Tubular and papillary changes can be negligible even in terminal uremia and drastic in cases of clinically preserved kidney function. In addition, the results indicate that not only tubular interstitial changes, but also isolated tubular or papillary distortions can develop at any stage of the disease. Thus 1H-NMR urinalysis is suitable for diagnosing latent tubular interstitial changes which are not readily detected by traditional techniques. This is important since early tubular intervention worsens the prognosis of the glomerulonephritis progression. Thus an approach enables identification of a group at risk of rapid deterioration of the disease among patients whose serum has normal creatinine levels. This additional information is valuable for the proper treatment of patients, and makes 1H-NMR urinalysis a prospective method for screening urine in glomerulonephritis. Further studies are required to decide whether the technique can be recommended for clinical practice.

[Environmental pollution and the characteristics of the epidemic process in diphtheria]. / Zagriaznenie okruzhaiushchei sredy i osobennosti épidemicheskogo protsessa difterii.

The analysis of materials for 1981-1993 on the city of Almaty and the Zhambyl, Aktyubinsk, East Kazakhstan and Kustanai provinces of the Republic of Kazakhstan made it possible to find out a number of specific features in diphtheria morbidity under the conditions of environmental pollution. It caused an increase in the number of the foci of the disease and in the proportion of bacterial carriers and diphtheria patients in the foci, the growth of the proportion of children among the patients and the proportion of toxic forms of diphtheria, the tendency towards a rise in the frequency of unfavorable outcomes of the disease. These features correspond to earlier data on the decreased immunological effectiveness of immunization with adsorbed DPT vaccine in the presence of environmental pollution in the above-mentioned territories.