The relationship between nonsuicidal self-injury, suicidal behaviour and life events among adolescents

Introduction

Nonsuicidal self-injury (NSSI) is highly prevalent in clinical and non-clinical adolescent populations. Non-clinical studies focus on high school students thus vocational school students are underrepresented in research and prevention programs, despite being exposed to higher levels of stressful life events, a factor associated with NSSI and suicide.

Objectives

This study aimed to explore NSSI, suicidal behavior and life events among adolescents in clinical and non-clinical, i.e. both high school and vocational school settings.

Methods

A clinical (n=202) and non-clinical (n=161) sample of 13-18-year-old adolescents were assessed with the Mini International Neuropsychiatric Interview Kid, the Deliberate Self-Harm Inventory, and the Life Events List. Data were analyzed with R version 3.6.1., using Wilcoxon tests and negative binomial regression models.

Results

The prevalence of suicidal behavior (W=7.306, p<.001), NSSI (W=9.652, p<.001), and life events (W=10.410 p<.001) were significantly higher in the clinical than in the non-clinical group. The relationship between NSSI and suicidal behaviour was significantly stronger in the clinical group (95% CI: [.56,.72]) than in the nonclinical group (95% CI: [.24,.52]). The interaction between NSSI and life events (Χ²(1)=10.49, p<.01) was associated with suicidal behavior. Interpersonal events were associated with both suicidal behavior and had a moderating effect on the NSSI–suicidal behavior relationship.

Conclusions

NSSI is highly prevalent and is strongly associated with suicidal behavior in clinical and non-clinical adolescent populations. Our result call attention to the necessity of including adolescents from various educational settings in NSSI research and prevention projects during which life events, especially interpersonal events, might require special attention.

Disclosure

No significant relationships.

Nonsuicidal self-injury, psychiatric disorders and pathological internet use among adolescents

Introduction

Previous studies underline the importance of internalising disorders as risk factors of nonsuicidal self-injury (NSSI), meanwhile only a few research draw the attention to the role of externalising disorders. The possible association between NSSI and pathological internet use (PIU) is also understudied.

Objectives

The purpose of this study was: 1) to investigate the frequency of NSSI among adolescents with different psychopathology and in different internet user groups of adolescents, 2) to understand the mediator role of psychiatric disorders between NSSI and PIU.

Methods

Adolescents were enrolled from a clinical (Vadaskert Child Psychiatric Hospital, Budapest, Hungary) and a school based population (high schools in Budapest, Hungary). The used measurements were: Strengths and Difficulties Questionnaire (SDQ), Deliberate Self-Harm Inventory, Young Diagnostic Questionnaire for Internet Addiction, Mini International Neuropsychiatric Interview Kid.

Results

There was significant difference in the frequencies of NSSI in SDQ subgroups (U=2127.000; z=-6.170; p <0.001). There was also significant difference in NSSI frequency between normal- and pathological internet users (U=2020.000; z=-2,501; p <0.017 p=0.012). According to the mediator model there was no direct association between PIU and NSSI, however it was mediated by different psychiatric disorders (affective disorders, anxiety disorders, attention deficit/hyperactivity disorder, conduct disorder, opposition defiant disorder, psychoactive substance abuse/dependence, psychotic disorders, suicidal behavior).

Conclusions

The results strengthen that both internalising- and externalising psychopathology are associated with NSSI. Moreover this study underlines the importance of careful screening and treating of comorbid disorders with PIU, which can have a role in the prevention of NSSI and suicide as well.

Disclosure

No significant relationships.

From farmers to livestock keepers: a typology of cattle production systems in south-western Burkina Faso

Cattle production is an essential livelihood strategy in south-western Burkina Faso. Although having a distinct cultural role and known to be resistant against African animal trypanosomosis, the Lobi taurine cattle breed is endangered due to its low market value. As the first step in preservation efforts, our study aimed to develop a typology of production systems at the farm level. We used a structured questionnaire and focus group discussions for collecting data on household characteristics, socioeconomic activities, livestock, and access to services. The sample comprised 169 households in three communities. The analytical strategy included factor analysis of mixed data and hierarchical clustering. We identified four distinct types of cattle production systems: (1) sedentary Lobi farms, (2) sedentary crossbreed farms, (3) semi-transhumant Fulani zebu farms, and (4) transhumant Fulani zebu farms. Significant factors in developing this typology were the farmers’ ethnic group, crop diversity, cattle herd size, cattle herd composition, number of small ruminants, and livestock management strategies. Across all production systems, men were considered being primary decision-makers in cattle production, with women, herders, and children being responsible for specific tasks. All identified production systems are increasingly confronting disease pressure and scarcity of water and land. Future efforts in preservation and breeding will need to respond to these trends in the agroecosystem, integrate risk management measures, and resonate with the specific needs of the different household members involved in cattle rearing.

Genome-wide mapping of the dominance effects based on breed ancestry for semen traits in admixed Swiss Fleckvieh bulls

Heterosis is the beneficial deviation of crossbred progeny from the average of parental lines for a particular trait. Heterosis is due to nonadditive genetic effects with dominance and epistatic components. Recent advances in genotyping technology have encouraged researchers to estimate and scan heterosis components for a range of traits in crossbred populations, applying various definitions of such components. In this study, we defined the intralocus (dominance) component of heterosis using local genetic ancestry and performed genome-wide association analysis for admixed Swiss Fleckvieh bulls and their parental populations, Red Holstein Friesian and Swiss Simmental, for semen traits. A linear mixed model for 41,824 SNP, including SNP additive genetic, breed additive, and breed dominance effects on 1,178 bulls (148 Red Holstein Friesian, 213 Swiss Simmental, and 817 Swiss Fleckvieh) with a total of 43,782 measurements was performed. In total, 19 significant regions for breed dominance were identified for volume (2 regions on Bos taurus autosome 10 and 22) and percentage of live spermatozoa (17 regions on Bos taurus autosome 3, 4, 5, 7, 13, 14, and 17), and genes associated with spermatogenesis, sperm motility, and male fertility traits were located there. No significant region for breed dominance was detected for total number of spermatozoa. The signals for breed dominance were relatively wide, most likely due to limited numbers of recombination events in a small number of generations (10-15 generations) of crossbreeding in the recent Swiss Fleckvieh composite.

Fast Data Sorting with Modified Principal Component Analysis to Distinguish Unique Single Molecular Break Junction Trajectories

A simple and fast analysis method to sort large data sets into groups with shared distinguishing characteristics is described and applied to single molecular break junction conductance versus electrode displacement data. The method, based on principal component analysis, successfully sorts data sets based on the projection of the data onto the first or second principal component of the correlation matrix without the need to assert any specific hypothesis about the expected features within the data. This is an improvement on the current correlation matrix analysis approach because it sorts data automatically, making it more objective and less time consuming, and our method is applicable to a wide range of multivariate data sets. Here the method is demonstrated on two systems. First, it is demonstrated on mixtures of two molecules with identical anchor groups and similar lengths, but either a π (high conductance) or a σ (low conductance) bridge. The mixed data are automatically sorted into two groups containing one molecule or the other. Second, it is demonstrated on break junction data measured with the π bridged molecule alone. Again, the method distinguishes between two groups. These groups are tentatively assigned to different geometries of the molecule in the junction.

Effects of breed proportion and components of heterosis for semen traits in a composite cattle breed

The aim of this study was to estimate the non-additive genetic effects of the dominance component of heterosis as well as epistatic loss on semen traits in admixed Swiss Fleckvieh, a composite of Simmental (SI) and Red Holstein Friesian (RHF) cattle. Heterosis is the additional gain in productivity or fitness of cross-bred progeny over the mid-purebred parental populations. Intralocus gene interaction usually has a positive effect, while epistatic loss generally reduces productivity or fitness due to lack of evolutionarily established interactions of genes from different breeds. Genotypic data on 38,205 SNP of 818 admixed, as well as 148 RHF and 213 SI bulls as the parental breeds were used to predict breed origin of alleles. The genomewide locus-specific breed ancestries of individuals were used to calculate effects of breed difference as well as the dominance component of heterosis, while proxies for two definitions of epistatic loss were derived from 100,000 random pairs of loci. The average Holstein Friesian ancestry in admixed bulls was estimated 0.82. Results of fitting different linear mixed models showed including the dominance component of heterosis considerably improved the model adequacy for three of the four traits. Inclusion of epistatic loss increased the accuracy of the models only for our new definition of the epistatic effect for two traits, while the other definition was so highly correlated with the dominance component that statistical separation was impossible.

Locus-specific ancestry to detect recent response to selection in admixed Swiss Fleckvieh cattle

Identification of selection signatures is one of the current endeavors of evolutionary genetics. Admixed populations may be used to infer post-admixture selection. We calculated local ancestry for Swiss Fleckvieh, a composite of Simmental (SI) and Red Holstein Friesian (RHF), to infer such signals. Illumina Bovine SNP50 BeadChip data for 300 admixed, 88 SI and 97 RHF bulls were used. The average RHF ancestry across the whole genome was 0.70. To identify regions with high deviation from average, we considered two significance thresholds, based on a permutation test and extreme deviation from normal distribution. Regions on chromosomes 13 (46.3-47.3 Mb) and 18 (18.7-25.9 Mb) passed both thresholds in the direction of increased SI. Extended haplotype homozygosity within (iHS) and between (Rsb) populations was calculated to explore additional patterns of pre- and post-admixture selection signals. The Rsb score of admixed and SI was significant in a wide region of chromosome 18 (6.6-24.6 Mb) overlapped with one area of strong local ancestry deviation. FTO, with pleiotropic effect on milk and fertility, NOD2 on dairy and NKD1 and SALL1 on fertility traits are located there. Genetic differentiation of RHF and SI (F_st ), an alternative indicator of pre-admixture selection in pure populations, was calculated. No considerable overlap of peaks of local ancestry deviations and F_st was observed. We found two regions with significant signatures of post-admixture selection in this very young composite, applying comparatively stringent significance thresholds. The signals cover relatively large genomic areas and did not allow pinpointing of the gene(s) responsible for the apparent shift in ancestry proportions.

The use of coancestry based on shared segments for maintaining genetic diversity

We have evaluated the use of genomic coancestry coefficients based on shared segments for the maintenance of genetic diversity through optimal contributions methodology for populations of three different Austrian cattle breeds. This coancestry measure has been compared with the genomic coancestry coefficient calculated on a SNP-by-SNP basis and with pedigree-based coancestry. The regressions of the shared segments coancestry on the other two coefficients suggest that the former mainly reflect Identity By Descent but with the advantage over pedigree-based coancestry of providing the realized Identity By Descent rather than an expectation. The effective population size estimated from the rate of coancestry based on shared segments was very similar to those obtained with the other coefficients and of small magnitude (from 26.24 to 111.90). This result highlights the importance of implementing active management strategies to control the increase of inbreeding and the loss of genetic diversity in livestock breeds, even when the population size is reasonably large. One problem for the implementation of coancestry based on shared segments is the need of estimating the gametic phases of the SNPs which, given the techniques used to obtain the genotypes, are a priori unknown. This study shows, through computer simulations, that using estimates of gametic phases for computing coancestry based on shared segments does not lead to a significant loss in the diversity maintained. This has been shown to be true even when the size of the population is very small as it is usually the case in populations subjected to conservation programmes.

GRAIN: a computer program to calculate ancestral and partial inbreeding coefficients using a gene dropping approach

GRain is freely available software intended to enable and promote testing of hypotheses with respect to purging and heterogeneity of inbreeding depression. The program is based on a stochastic approach, the gene dropping method, and calculates various coefficients from large and complex pedigrees. GRain calculates, together with the 'classical' inbreeding coefficient, ancestral inbreeding coefficients proposed by Ballou, (1997) J. Hered., 88, 169 and Kalinowski et al., (2000) Conserv. Biol., 14, 1375 as well as an ancestral history coefficient (AHC ), defined here for the first time. AHC is defined as the number that tells how many times during pedigree segregation (gene dropping) a randomly taken allele has been in IBD status. Furthermore, GRain enables testing of heterogeneity and/or purging of inbreeding depression with respect to different founders/ancestors by calculating partial coefficients for all previously obtained coefficients.

Altered mitochondrial response to activation of T-cells in neonate

Mitochondrial functions have a major impact on T-cell functionality. In this study we characterized whether mitochondrial function in the neonatal T-cells differs from that in the adult T-cells during short T-cell activation.

METHODS

We used flow cytometry methods to test mitochondrial mass and to monitor mitochondrial Ca²⁺ levels, mitochondrial potential and superoxide generation in parallel with cytoplasmic Ca²⁺ levels during phythohaemagglutinine-induced activation of CD4+ and CD8+ T-cells of 12 term neonates and 11 healthy adults.

RESULTS

Baseline mitochondrial mass of CD4+ and CD8+ cells was lower in the neonate than in the adult. In comparison with the adult, neonatal resting CD4+ T-cells had lower cytoplasmic Ca²⁺ levels and this was associated with normal activation induced Ca²⁺-response. During short-term activation cytoplasmic Ca²⁺-response was lower in neonatal than in adult CD8+ T-cells. Mitochondrial Ca²⁺ uptake was increased in CD4+ neonatal T cells while it decreased in CD8+ T-cells. Mitochondrial depolarization was increased in CD4+ and decreased in CD8+ neonatal T-cells compared to adults. Superoxide generation was higher and equal in neonatal CD4+ and CD8+ cells, respectively, compared to the adult ones.

CONCLUSION

Our data suggest that neonatal T-cells exhibit marked differences in mitochondrial function and superoxide generation compared to adult T-cells.

Investigation of the genetic distances of bovids and cervids using BovineSNP50k BeadChip

Abstract. This study presents the application of BovineSNP50 BeadChip for genome-wide screening of two taurine breeds (Bos primigenius taurus) and Zebu (Bos primigenius indicus), and two species from the family Cervidae: red deer (Cervus elaphus) and fallow deer (Dama dama). The aim of the paper was to evaluate the use of bovine array for cross-species genotyping and analyse single nucleotide polymorphism (SNP) distribution, diversity within groups of animals and genetic distance among analysed species. The number of polymorphic SNPs decreased with the increase of phylogenetic distance between species, which also reflected a decrease in call rate (from 99.54 to 61.19%). The minor allele frequency (MAF) values were significantly different between species and ranged from 0.18 ± 15 (Zebu) to 0.26 ± 0.14 (Pinzgau). The subsequent analyses of genetic diversity were based on the polymorphic loci detected in cervids. Differences in the expected heterozygosity was low (0.06), on average 0.34. In analysed groups the FIS values were close to zero, which suggested low SNP variance within them. The value of FIT indicated homozygote excess in evaluated individuals. Analysis of molecular variance revealed that most of the variability was distributed within all individuals. Observed genetic distances within and across groups of animals suggested that taurine cattle and cervids were more distant. The study results showed that genotyping array prepared for model species can be applied not only to organisms for which was developed, but can be also successfully used in closely related and more phylogenetically divergent species.

Evaluation of the length of competitive life in Hungarian sport horses

The aim of this study was to analyse the duration of the competitive life of jumping horses in Hungary to assess the potential for genetic evaluation and to get information about the risk factors affecting jumping performance of sport horses. The data set included lifetime performance in jumping competitions for 8475 horses born from 1992 onwards with records between 1996 and 2011 (32.7% were right-censored). Longevity was measured as the number of years spent in the competition. Discrete time survival model included fixed effects of gender, age at first competition, and the time-dependent effect of competition level. All fixed effects were highly significant (p < 0.001). The highest risk of ending the race career was estimated for horses competing in the lowest level (category 1) events. The smallest risk was found in horses competing in the highest category. The culling risk for stallions was 15% higher, for geldings 20% lower when compared to mares. As the age at the first competition result increased, the risk ratio also increased. Risk ratios of horses starting as 8 years old or older were 56% higher than those of 5-year-old horses. The longest time in sport tracks belonged to horses starting their career as 4 years old. Their culling risk was 20% lower than those of 5-year-old horses. The heritability of the length of competitive life was 0.17. Breeding values were predicted for each animals, and 47 showed an accuracy greater than 0.60. The clear benefit of the analysis was shown by comparison of offspring to extreme stallion groups.

The Survival Kit: software to analyze survival data including possibly correlated random effects

The Survival Kit is a Fortran 90 Software intended for survival analysis using proportional hazards models and their extension to frailty models with a single response time. The hazard function is described as the product of a baseline hazard function and a positive (exponential) function of possibly time-dependent fixed and random covariates. Stratified Cox, grouped data and Weibull models can be used. Random effects can be either log-gamma or normally distributed and can account for a pedigree structure. Variance parameters are estimated in a Bayesian context. It is possible to account for the correlated nature of two random effects either by specifying a known correlation coefficient or estimating it from the data. An R interface of the Survival Kit provides a user friendly way to run the software.

Effect of 3 months of doxazosin therapy on T-cell subsets in type 2 diabetic patients

Doxazosin, an alpha(1)-adrenergic receptor inhibitor, is commonly administered to patients with type 2 diabetes, hypertension and nephropathy. The impact of 3 months' doxazosin therapy on the prevalence of activated and regulatory T lymphocytes was analysed in this pilot study of men with type 2 diabetes (n = 10) who received doxazosin 4 mg/day in addition to their ongoing therapy. The prevalence of CD4(+), CD8(+), CD25(+) and CD69(+) cells at baseline and after 3 months of add-on therapy was determined. The prevalence of regulatory T-cells was detected by two different approaches: forkhead box P3 (FoxP3) positivity; and the number of CD4(+)CD25(+high) cells. During 3 months of doxazosin therapy, patients' blood pressure, blood glucose control and lipid profiles all significantly improved. Simultaneously, the prevalence of activated T-cells (CD4(+)CD69(+) and CD8(+)CD69(+) cells) decreased, whereas that of regulatory T-cells increased. These results indicate an immunomodulatory action of doxazosin in type 2 diabetic patients.

Genetic evaluation for length of productive life in Slovak Pinzgau cattle

Abstract. The proportional hazards method was used to estimate breeding values for functional length of productive life within the endangered Slovak Pinzgau population. The analyzed data set contained 21,985 cows, daughters of 254 sires. The risk of culling was higher for cows with lower milk production relative to herd average, higher age at first calving and in herds decreasing in size. In the first lactation the culling risk was highest at the beginning, and decreased during lactation. From second lactation onwards an increasing risk was observed. The effect of breed composition was found insignificant, and was not included into final model. A heritability of 0.05 was estimated for functional length of productive life. The average reliability of estimates was 0.25. No clear tendency in average breeding values by year of birth of bulls was observed.

The inhibitory effect of various indolyl amino acid derivatives on arginase activity in macrophages

Numerous indolyl amino acids and their derivatives inhibited arginase activity. The inhibition was found to be non-competitive, - at least partly - allosteric, and independent on manganese ions in the active site, and it cannot be explained by the dissociation of arginase homotrimers. Indole alone is weakly inhibitory; however, the presence of three-carbon side chains and their net charges is favorable for the inhibition. The binding of the inhibitory compounds caused only minor changes in the steric structure of arginase: a slight increase in alpha-helix content was detected by circular dichroism together with a decrease in parallel pleated sheet and beta-turn sections. A slight alteration in the tertiary structure was also found using tryptophane fluorescence studies, but buried apolar side chains were not transposed to the protein surface. Computer studies that were performed did not provide additional structural information.

Activation of caspase-3 protease during the process of ursolic acid and its derivative-induced apoptosis

The apoptosis-inducing effect of the triterpene saponins, namely, ursolic acid and its natural derivative, methyl-ursolate beta-D-glucoside on A431 human epidermoid carcinoma cells was studied. The cells treated with 5-50 microg/ml of ursolic acid resulted in a dose- and time-dependent decrease in cell number, due to an increase of apoptotic cells as evidenced by MTT assay together with morphological changes. The highest dose (50 microg/ml) of ursolic acid resulted in approximately 90% inhibition in tumor cell growth after 96 hours of treatment and 60% of apoptosis after 48 hours. To the contrary, when the same treatment was carried out with methyl-ursolate beta-D-glucoside, after 96 hours of treatment the percentage of cell growth inhibition was found to be only 30% at the dose of 50 microg/ml and the value of apoptosis did not exceed 10%. Similarly to these results, ursolic acid effectively induced proteolytic activation of caspase-3 protease in a dose-dependent manner while its derivative showed only weak activity in this enzyme assay. The addition of DEVD-CHO prior to ursolic acid and methyl-ursolate beta-D-glucoside treatment effectively prevented the loss of triterpenes-induced viability. In summary, the triterpene saponins investigated contain an apoptotic-inducing activity in A431 cells and in the case of ursolic acid it is associated with proteolytic activation of caspase-3 and/or other similar caspases. Our results also indicated that methylation of COOH-28 together with the glycosylation of C3 of ursolic acid have a strong impact on its antitumor activity.

Chlamydia trachomatis infection and the risk of perinatal mortality in Hungary

INTRODUCTION

Chlamydial infections of the genital tract are thought to often lead to preterm birth, which is the most important perinatal problem in Hungary.

AIM OF STUDY

A multicenter study was carried out to determine the prevalence of Chlamydia trachomatis infection, risk factors for the infection and to relate the infection to perinatal mortality, accounting for potential confounding effects.

METHODS

The nucleic acid hybridization method (PACE2 Gen-Probe) was applied for the examination of Chlamydia trachomatis. Logistic regression analysis was used to assess risk.

RESULTS

A total of 6156 pregnancy women were examined for the occurrence of Chlamydia trachomatis. The observed overall rate of chlamydial infection was 5.9%. Young age (less than 24 years old) (OR and 95% CI: 1.6 (1.3-2.0)), unmarried status (1.5 (1.2-1.9)) and the high unemployment rate (2.1 (1.6-2.7)) were statistically significant predictors of the infection. In logistic regression analysis, chlamydial infection (1.9 (1.1-3.3)), high unemployment rate (1.5 (1.2-2.2)) and low birth weight (1.7 (1.1-2.7) were significant predictors of perinatal mortality.

CONCLUSIONS

Testing pregnant women for diseases that can be transmitted perinatally is an important part of obstetric care. Screening for C. trachomatis of unmarried women under 24 years of age is suggested and need increased observation during labor.

Screening for Chlamydia trachomatis in asymptomatic women in Hungary. An epidemiological and cost-effectiveness analysis

BACKGROUND

A multicenter survey was carried out in order to determine the prevalence and risk factors for Chlamydia trachomatis infection in the population of asymptomatic women in Hungary. Results were used to carry out a cost-effectiveness analysis of screening for chlamydial infection in women with asymptomatic genital infections.

METHODS

The non-amplified nucleic acid hybridization method (PACE 2 Gen-Probe) was used to diagnose C. trachomatis and Bayes' theorem was applied to assess the prevalence of the infection. Multiple logistic regression analysis was performed to differentiate the risk factors for chlamydial infections.

RESULTS

According to the test, the prevalence of Chlamydia trachomatis among 1300 pregnant women was 4.5%. The sensitivity and specificity of the test are estimated to be 70% and 99%, respectively. After Bayes' correction, the overall estimated prevalence of chlamydial infection was 5.1%. There were significant differences in proportions of chlamydial infection in different regions, and also in different age groups and different family status groups. The highest rate was for women aged below 20 years: 16.9%. Cost-effectiveness analysis, with associated sensitivity analysis was carried out for women aged below 20 years. Three screening strategies were compared: using the ELISA method, using amplified Gen-Probe method and no screening. The amplified Gen-Probe method was best provided, the infection prevalence exceeded 16.7%, the PID rate exceeded 24% and the probability of tubal infertility in untreated women exceeded 25%.

CONCLUSION

We conclude that screening with amplified Gen-Probe assays (followed by treatment of positive patients) is the preferred screening strategy for young women in Hungary.

Cytostatic, cytotoxic and protein tyrosine kinase inhibitory activity of ursolic acid in A431 human tumor cells

The effect of the tritepene, ursolic acid, on the proliferation of A431 human epidermoid carcinoma cells was studied. According to our investigations, ursolic acid is a potent inhibitor of A431 cell growth. Ursolic acid markedly reduced A431 cell growth in a time- and dose-dependent manner. We found a good correlation between the results of direct cell counting and the MTT test. During long periods of drug exposure, ursolic acid exhibited both cytotoxic and cytostatic activity. The effect was partially reversible on drug removal. The greatest cytotoxicity was observed both in the trypan blue test and in the MTT test at 50 mM. Investigations on tyrosine kinase inhibition were performed by biochemical and cellular assays on A431 cells. Ursolic acid inhibited tyrosine kinase activity of A431 cells in biochemical assay in a dose-dependent manner with an IC50 of 24 mM. In cellular assay, when A431 cells were pretreated with ursolic acid for 24, 48 and 168 hours at various concentrations (5, 10, 20, 30 and 50 mM), lower values of IC50 were measured: 6.8 microM for 24 hours, 5.2 mM for 48 hours and 1.4 mM for 168 hours. The results suggest that ursolic acid exerts an antiproliferative effect through the inhibition of tyrosine kinase enzymes.

[Potentials of screening for Chlamydia trachomatis in Hungary: cost-benefit analysis]

Untreated chlamydial infections of the genital tract may cause a wide range of serious complications, which could be prevented by screening. Cost-effectiveness analysis based on previously reported epidemiological study among pregnant women was carried out to develop and evaluate cost-effectiveness of age-based screening (women younger than 20 years old) for Chlamydia trachomatis in Hungary. Three kind of screening strategies were used: a) no screening, b) screening by using ELISA test and c) screening by amplified Gen-Probe diagnostic test. Young age and unmarried status were significant predictors of the chlamydial infection. Prevalence of chlamydial infection was 11.4% in the group of age younger then 20 years. Strategy b) was more cost-effective than neither testing nor treating. Strategy c) was less cost-effective than non screening, unless certain conditions were satisfied. If the cost of the diagnostic test were less or equal than 2,000 HUF or the prevalence of infection in women were greater than 17%, screening strategy c) would be more cost-effective than no screening. Although screening by using ELISA test was more cost-effective than screening by amplified Gen-Probe test, additionally 10,000 infected cases could be prevented using amplified Gen-Probe method for screening Chlamydia trachomatis.

[Problems of treating burn injuries in Hungary in the light of advancements during the last half century]

Until the middle of 20th century the burnt patients were treated on dermatological departments, and skin transplantations were performed after the regular conservative wound care too late and rarely. By reason of the medical experiences of the 2nd World War special departments were founded for the burn-injured patients, it happened likewise in our country in 1953 as well. The specialists recognized that the burn injury causes a general disease (multiple organ failure), moreover only an aggressive surgical tactics can product any good results. The author presents the progress and problems of Hungarian burn treatment since 1953. A significant part of the burnt patients has been treated firstly not in burn departments, and sometimes the first therapy is insufficient, because the national medical training for cure of burnt patients is deficient. For this reason the author gives a simple treatment guide for the first two postburn days, and finally he summarizes the conditions of advance.

[Preparation and characterization of potential antineoplastic agents]

A parallel combinatorial library of over sixteen hundred compounds has been designed and synthesized for the development of new potential peptidomimetic protein tyrosine kinase (PTK) inhibitor leads that is aimed for intervening with the substrate binding site of the pp60c-src enzyme. The new structures were based on known PTK inhibitors having at least two variously substituted aromatic moieties attached by spacer groups of different length and flexibility. Eleven bis-aryl type inhibitory compounds were found in the range of 18-100 micromolar IC50 concentrations from combinations of twelve different substituents. Molecular modeling of the active compounds showed a characteristic distance of 13-14 A between the farthest sp2 carbon atoms of the two aromatic rings. Conformational analysis of several peptide substrates recently found for pp60c-src PTK [5,6,7] showed that the energy minimized conformers had the same distance between two aromatic moieties. Several compounds in the library not only showed remarkable PTK inhibitory activity but also a significant apoptosis inducing effect on HT-29 human colon tumor cells.

A novel normalized retention factor in micellar electrokinetic chromatography

Characteristic properties of the expression k'' = (t(m)-t(o))/(t(mc)-t(o)) and its applicability in micellar electrokinetic capillary chromatography (MEKC) were compared to the previous expression, k' = (t(m)-t(o))/t(o)(1-t(m)/t(mc)), introduced by Terabe. It was proved with theoretical calculations (curve shape analysis) that the properties of function k'' are in full accordance with the properties of the MEKC system and k'' could be applied advantageously to characterize hydrophobicity of the analytes. This conclusion is now supported by experimental data obtained with homolog series of alkylbenzenes and alkylphenones as well as with hydrophobic protected peptides. Migration times, k', k'' values, and software-calculated hydrophobicity data are summarized and analyzed in the present study. Since k'' is a normalized parameter, good relationships between the migration time, the software-calculated hydrophobicity, and the k'' values were obtained. Differences in hydrophobicity of the analytes could be estimated in a more realistic way with the aid of function k'' than by using function k'. Hydrophobicity data estimated on the basis of the k'' values proved to be in good accordance with the expectations based on the migration times and on the chemical structures of the compounds investigated.

The frequency and the role of Chlamydia trachomatis infection in premature labor

OBJECTIVE

The importance of Chlamydia trachomatis (C. tr.) infection in the etiology of premature labor was examined in a prospective, representative, multicenter study.

METHOD

Specimens were collected from 6161 subjects in seven centers and examined by the Gen-Probe method.

RESULTS

The infection rate was 5.74%. There were no significant correlations between low birth weight, premature rupture of the membranes, dysmaturity and C. tr. infection. In cases of threatening premature labor, the infection rate was significantly higher in C. tr.-positive patients. In the event of combined low birth weight and perinatal death, the maternal C. tr. infection rate was significantly higher than in normal pregnancies. C. tr.-positive patients treated with roxithromycin had term deliveries. A correlation between poor social circumstances and a high C. tr. infection rate could be proved.

CONCLUSION

Cases with a poor obstetric history and/or socially high-risk patients should be screened for C. tr. infection, and in positive cases treatment is recommended.

Epidemiological study of Chlamydia trachomatis infection in pregnant women in Hungary

A multicentre survey was carried out in order to determine the prevalence and risk factors of Chlamydia trachomatis infection in the pregnant population in Hungary. The nucleic acid hybridisation method (PACE 2 Gen-Probe) was applied for the examination of C trachomatis. The overall average prevalence of C trachomatis cases during an 18 month survey on 6161 pregnant women was 5.87%. There were significant differences in the proportions of chlamydial infection in the different survey centres, and also in the different age groups and the different family status groups. The perinatal mortality rate exhibited a significantly higher prevalence (8.52%) among C trachomatis positive than among negative patients (2.03%). In the anamnestic histories of C trachomatis infected patients, the frequency of premature uterine activity was 8.13%, in contrast with 5.18% in the non-infected group (p < 0.05). We suggest that all pregnant women be tested for C trachomatis infection.

Prevalence of Chlamydia trachomatis infection in a low-risk population in Hungary

BACKGROUND AND OBJECTIVE

Chlamydia trachomatis is the leading cause of nongonococcal urethritis and cervicitis in women. Because of the recent increases in the numbers of new cases and severe consequences, there is an urgent demand for the introduction of sensitive and specific rapid diagnostic methods.

GOAL

A multicenter examination involving seven centers was sponsored by the Hungarian Ministry of Health and Welfare in order to provide a survey of Chlamydia trachomatis in the gravid population. 6,161 women were tested between 1994 to 1995.

STUDY DESIGN

The seven centers were selected with regard to different aspects, from developed and less developed areas in the capital, two large provincial towns, and various other provincial regions reflecting either an industrial or an agricultural background. The nucleic acid hybridization method (PACE 2 Gen-Probe, San Diego, CA) was introduced in this low-risk population for the examination of Chlamydia trachomatis. In one center, a further two methods, antigen detection by ELISA (SYVA, CA) and cultivation on the McCoy cell line (staining with SYVA FITC-labeled antichlamydia monoclonal antibody), were applied.

RESULTS

International surveys and experience indicate that the proportion of the population threatened by Chlamydia trachomatis is above 10%. The overall average incidence of Chlamydia trachomatis cases in this low-risk gravid population was 5.74%. The data from the different centers ranged between 1.6% and 9.7%. The chlamydia-infected Hungarian gravid population is below the critical 10%, but there is one Hungarian county where the value is close to 10%.

CONCLUSIONS

In this provincial, industrial area, the number of unmarried and divorced gravida in a low economic situation is disproportionately high. For this disadvantaged population, permanent Chlamydia trachomatis screening was suggested. In the other centers, screening of pregnant women for Chlamydia trachomatis and the treatment of positive cases and their partners were suggested for pathological gravida with preterm labor and preterm rupture of the membranes.

Ascorbate as a substrate for glycolysis or gluconeogenesis: evidence for an interorgan ascorbate cycle

Ascorbate catabolism was investigated in murine and human cells unable to synthesize ascorbate due to the missing gulonolactone oxidase activity. In HepG2 cells the addition of ascorbate or dehydroascorbate resulted in high glucose production, while human erythrocytes, MCF7 cells and the cellular elements of the murine blood were able to metabolize ascorbate or dehydroascorbate to lactate. The oxidative agent menadione stimulated, while the transketolase inhibitor oxythiamine inhibited, the metabolism of dehydroascorbate in each of these three cell types. Our results suggest that ascorbate breakdown through the pentose phosphate pathway can reach the glycolytic/gluconeogenic route in different cells. In ascorbate synthesizing species the ascorbate-lactate route in peripheral cells may form a catabolic branch of an interorgan ascorbate cycle, where hepatocytes are responsible for ascorbate synthesis. The catabolic part of this cycle using exogenous ascorbate could be demonstrated even in humans cells.

Analysis of macromolecular branched chain polypeptides by capillary electrophoresis and micellar electrokinetic chromatography

Amphoteric poly(Lys-[Glu1.0-DL-Ala4.1]), (EAK) and anionic poly(Lys-Ac-Glu0.98-DL-Ala3.98]), (AcEAK) branched chain polypeptides were analyzed by capillary electrophoresis (CE) and micellar elektrokinetic chromatography (MEKC) in the following buffers. A1: 0.25 N triethyl ammonium phosphate (TEAP) buffer (pH 2.25); A2: 100 mM sodium dodecyl sulfate (SDS) in buffer A1; B1: Na-borate buffer (pH 7.7); B2: 100 mM SDS in buffer B1; C1: Na-borate buffer (pH 11.0); C2: 100 mM SDS in buffer C1. Both EAK and AcEAK could be separated by a CE mechanism at pH 2.25 and by an MEKC mechanism at pH 11.0. Optimum results were achieved with CE in buffer A1 and with MEKC in buffer C2.

The inhibitory effect of nitrite, a stable product of nitric oxide (NO) formation, on arginase

Macrophages contain arginase and an inducible NO synthase, demonstrated by using L-arginine, the common substrate, for production of both nitric oxide and urea. Arginase was inhibited by nitrite, the stable end product of NO. This inhibition was non-competitive, and could not be explained by the reaction of nitrite with arginine, or by the irreversible covalent modification of arginase, or by the removal of Mn2+, a cofactor of arginase.

Calcium-dependent nitric oxide synthesis is potently stimulated by tetrahydrobiopterin in human primordial placenta

Homogenized first trimester human placenta exhibits both Ca(2+)-dependent (90-95 per cent) and Ca(2+)-independent (5-10 per cent) nitric oxide (NO)-synthesizing activities. Addition of tetrahydrobiopterin (BH4) to homogenates containing Ca2+ in maximally activating concentrations (> 0.5 microM) results in a further 2-2.5-fold activation of NO synthesis, with half-maximal stimulation observed at 26 +/- 8.2 microM BH4 (mean +/- SEM, n = 4). Chelation of Ca2+ in the medium abolishes the stimulatory effect, indicating that only a Ca2(+)-dependent NO-synthase (NOS) isoform is activated by BH4. Based on our previous findings, we suggest that this isoform is the endothelial or Type III NOS. Importantly, BH4 has no significant effect on the Ca2(+)-dependency of NOS activity, the apparent Km values for Ca2+ are comparable in the absence (1.8 +/- 0.4 microM, mean +/- SEM, n = 6) or presence (2.5 +/- 0.6 microM, mean +/- SEM, n = 6) of 50 microM BH4. The BH4 content of these placentae is 207.4 +/- 86.7 pmol/g wet tissue (mean +/- s.d., n = 9), therefore, BH4 added to the homogenate does not simply restore the concentrations that occur endogenously. The results provide the first evidence that in the early human placenta, a constitutively expressed CA 2(+)-dependent NOS isoform is stimulated by exogenous BH4, raising the possibility that BH4 is an important regulator of NOS activity in this tissue. This novel aspect of the NO-generating pathway may have implications in the aetiology and treatment of pregnancy-induced hypertension and pre-eclampsia.

[Weather front sensitivity as an influencing factor in the onset of labor]

The connection between meteorological stimuli and the onset of labor was examined on the basis of the patients' front-sensitivity. Front-sensitivity was tested by a questionary containing 60 questions. Converse relation was observed between the degree of sensitivity and the gestational age. A sudden rise of onsets of labors could be shown during frontal changes, occurred after meteorologically quiet periods. During frontal changes the ratio of onsets of labors rose significantly among those patients who were sensitive tho the given front. This effect could be observed during a longer period of frontal influence. By the authors opinion also meteorological stimuli can be regarded as one of the factors, determining the actual date of onset of labor among front-sensitive women.