Periodicity of arrhythmias in healthy elderly men at the moderate altitude. (17/518)

The 24-hour periodicity of supraventricular (SVPB) and ventricular (VEB) extrasystoles in healthy elderly men (age 49-69 years) was studied at two altitudes during 24 h Holter ECG monitoring. At the low altitude (200 m, n = 26), SVPB were more frequent than VEB. The highest occurrence of SVPB was at 17:00 h, the lowest at 01:00 and 02:00 h (P<0.001). The highest occurrence of VEB was at 09:00 h, the lowest one at 04:00 h (P<0.001). At 1350 m (n=9) the incidence of both SVPB and VEB was approximately twofold higher compared to that at the low altitude (P<0.001). The highest occurrence of SVPB was at 13:00 h, the lowest at 06:00 h (P<0.001). VEB were the most frequent at 10:00 h and 13:00 h, while the lowest frequency was observed at 06:00 h (P<0.001). Our results indicate that the incidence of SVPB and VEB in healthy persons at the moderate altitude is twofold and its periodicity is shifted compared to the low altitude. The cause of increased occurrence of extrasystoles is probably due to beta-adrenergic activation of the heart at the higher altitude.  (+info)

Variations in the major envelope glycoprotein GP5 of Czech strains of porcine reproductive and respiratory syndrome virus. (18/518)

The major envelope glycoprotein genes (ORF5) of seven Czech isolates of porcine reproductive and respiratory syndrome virus (PRRSV) were amplified and their nucleotide sequences were determined. ORF5 displayed nucleotide and amino acid identities of 87.5-100% and 87. 6-100%, respectively, among the isolates. In a phylogenetic tree, all European isolates were grouped in a genotype distinct from that of reference American strains (VR-2332, IAF-Klop). Among the European isolates, two different clades were identified. Two Czech isolates (V-501 and V-503) and Italian strain PRRSV 2156 fell into one clade. The remaining European strains comprised the second clade. Surprisingly, two separately clustered strains (V-501 and V-516) were isolated from the same herd. Additionally, the possible effect of in vitro cultivation on the nucleotide sequence was analysed. Nine point mutations in the ORF5 region resulted from 152 in vitro passages of the V-502 isolate in MARC-145 cells.  (+info)

Maternal socioeconomic characteristics and infant mortality from injuries in the Czech Republic 1989-92. (19/518)

OBJECTIVES: Infant and childhood mortality from injuries in Central and Eastern Europe is high but little is known about its determinants. This study examined whether maternal socioeconomic characteristics predict infant mortality from injuries in the Czech Republic. METHODS: Data on all live births registered in the Czech Republic 1989-91 (n=387 496) were linked with the national death register, 1989-92, using the unique national identification number. Effects of maternal socioeconomic characteristics, birth weight and gestational age, recorded in the birth register, on the risk of death from external causes (ICD-9 800-999) were estimated using logistic regression. RESULTS: Of the 195 linked infant deaths from external causes (rate 50/100000 live births), 73% were from suffocation. After controlling for other factors, the risk of death was higher in boys, declined with increasing maternal education (odds ratio for primary v university education 3.5, 95% confidence interval 1.5 to 8.6), maternal age, birth weight and gestational age, and was increased in infants of unmarried mothers and of mothers with higher parity. The effect of education appeared stronger in married mothers and in mothers of low parity. CONCLUSION: The risk of infant death from external causes in this population was strongly associated with maternal and family characteristics.  (+info)

Semen quality and reproductive health of young Czech men exposed to seasonal air pollution. (20/518)

This study of male reproductive health in the Czech Republic resulted from community concern about potential adverse effects of air pollution. We compared young men (18 years of age) living in Teplice, a highly industrialized district with seasonally elevated levels of air pollution, to those from Prachatice, a rural district with relatively clean air. Surveys were scheduled for either late winter, after the season of higher air pollution, or at the end of summer, when pollution was low. Participation included a physical examination, donation of a semen sample, and completion of a questionnaire on health, personal habits, and exposure to solvents and metals through work or hobby. Analysis of data from 408 volunteers showed that the men from Teplice and Prachatice were similar in physical characteristics, personal habits, and work- or hobby-related exposures. Sixty-six percent (272) of these men donated a single semen sample for routine semen analysis, computer-aided sperm motion analysis, and sperm chromatin structure assay. The mean (median) sperm concentration and sperm count were 61. 2 (44.0) million/mL semen and 113.3 (81.5) million, respectively, and were not associated with district of residence or period of elevated air pollution. However, periods of elevated air pollution in Teplice were significantly associated with decrements in other semen measures including proportionately fewer motile sperm, proportionately fewer sperm with normal morphology or normal head shape, and proportionately more sperm with abnormal chromatin. These results suggest that young men may experience alterations in sperm quality after exposure to periods of elevated air pollution, without changes in sperm numbers.  (+info)

Variable expression of hypercholesterolemia in Apolipoprotein E2* (Arg136 --> Cys) heterozygotes. (21/518)

In the process of population screening for apo E gene polymorphism with the PCR and subsequent restriction analysis, we identified a female who demonstrated heterozygosity for an unusual restriction fragment caused by the loss of a CfoI restriction site. Sequence analysis of the apo E gene was performed and a carrier of the mutant allele with C --> T substitution at cDNA position 3817 was identified, which caused an Arg136 --> Cys change. The first-line relatives have been screened for this rare mutation with PCR and restriction analysis of PCR products. The complete lipoprotein parameters have been determined in the probands family. In the family, only one child had the same mutant allele as his mother had. The proband (7.49 mmol/l) with her siblings had hypercholesterolemia and a high body mass index (BMI 31.6 kg/m2). By contrast, her son had a normal lipid spectrum with normal BMI. We described the mutation apo E2* (Arg136 --> Cys) in a family with elevated lipid levels, but there was no confirmation of the connection between this mutation and type III hyperlipoproteinemia or hyperlipoproteinemia at all. In the case of this mutation, other factors (mainly genetic) are important for the development of lipid metabolism disorders.  (+info)

Recognition of two novel phenons of the genus Acinetobacter among non-glucose-acidifying isolates from human specimens. (22/518)

Genomic species diversity among 147 Acinetobacter clinical isolates not belonging to the A. calcoaceticus- A. baumannii (ACB) complex was investigated by phenotypic and genotypic identification methods. The isolates were obtained between 1991 and 1999 from numerous diagnostic laboratories in the Czech Republic and were studied by numerical probabilistic identification using two biochemical frequency matrices and amplified rDNA restriction analysis (ARDRA). Their final identification was derived from the combined phenotypic and ARDRA results. In total, 102 isolates were unambiguously (n = 89) or presumptively (n = 13) identified as A. lwoffii (n = 63), genomic species 13BJ/14TU (n = 9), A. johnsonii (n = 7), A. haemolyticus (n = 6), A. junii (n = 5), and other genomic species (n < 5 isolates each). Forty-five isolates could not be identified as belonging to any described species. Among the unidentified isolates two large groups of non-glucose-acidifying, nonhemolytic, and non-gelatinase-producing isolates were distinguished. These groups, designated phenon 1 (n = 17) and phenon 2 (n = 15), had distinctive phenotypic features and novel ARDRA profiles, which suggests that they represent hitherto undescribed Acinetobacter species. Phenon 2 included mainly clinically insignificant isolates from outpatients, while phenon 1 comprised clinically relevant isolates mostly from the blood of hospitalized patients, and its precise taxonomic definition may therefore be of medical importance. Overall, the development of practical methods for identification required for the elucidation of the biological significance of the (genomic) species within the genus Acinetobacter remains a challenging task.  (+info)

Clinical ascertainment of Nijmegen breakage syndrome (NBS) and prevalence of the major mutation, 657del5, in three Slav populations. (23/518)

Nijmegen breakage syndrome (NBS) is a chromosomal instability disorder, clinically characterised by microcephaly, immunodeficiency, radiosensitivity and a very high predisposition to lymphoid malignancy. Recently, it was demonstrated that mutations in the NBS1 gene are responsible for NBS. Most of the NBS patients known so far are of Slav origin and carry a major founder mutation 657del5 in exon 6 of the NBS1 gene. In this study we estimated the prevalence of the 657del5 mutation in the Czech Republic, Poland and the Ukraine. We found an unexpectedly high carrier frequency of the 657del5 mutation (1/177) in the three Slav populations, a factor that may contribute to cancer frequency in those countries. In addition, we show that NBS patients are often diagnosed late and therefore receive inappropriate therapy.  (+info)

Carried meningococci in the Czech Republic: a diverse recombining population. (24/518)

Population and evolutionary analyses of pathogenic bacteria are frequently hindered by sampling strategies that concentrate on isolates from patients with invasive disease. This is especially so for the gram-negative diplococcus Neisseria meningitidis, a cause of septicemia and meningitis worldwide. Meningococcal isolate collections almost exclusively comprise organisms originating from patients with invasive meningococcal disease, although this bacterium is a commensal inhabitant of the human nasopharynx and very rarely causes pathological effects. In the present study, molecular biology-based techniques were used to establish the genetic relationships of 156 meningococci isolated from healthy young adults in the Czech Republic during 1993. None of the individuals sampled had known links to patients with invasive disease. Multilocus sequence typing (MLST) showed that the bacterial population was highly diverse, comprising 71 different sequence types (STs) which were assigned to 34 distinct complexes or lineages. Three previously identified hyperinvasive lineages were present: 26 isolates (17%) belonged to the ST-41 complex (lineage 3); 4 (2.6%) belonged to the ST-11 (electrophoretic type [ET-37]) complex, and 1 (0.6%) belonged to the ST-32 (ET-5) complex. The data were consistent with the view that most nucleotide sequence diversity resulted from the reassortment of alleles by horizontal genetic exchange.  (+info)