The importance of being heterozygote: effects of RHD-genotype-sex interaction on the physical and mental health of a non-clinical population.

Human populations, especially European, are polymorphic in the RHD gene. A significant fraction of their members carry no copy of the coding section of RHD gene, which results in their Rh-negative blood type. Theoretically, this polymorphism should be unstable. Carriers of the less frequent allele are penalized by reduced fertility because of the immunization of RhD-negative mothers by their RhD-positive babies, which results in hemolytic disease of the fetus and newborn in their subsequent progeny. For about 90 years, some form of balancing selection has been suspected to sustain this polymorphism. Several recent studies showed that the RhD-positive heterozygotes express higher viability than both types of homozygotes. However, the genotype of subjects in these studies was estimated only by indirect methods. Here we compared the physical and mental health of 178 women and 86 men who were directly tested for their RHD genotype. The results showed that RhD-positive homozygotic women had worse and RhD-positive homozygotic men better physical health than RhD-negative homozygotes; the difference between RhD-negative homozygotes and heterozygotes was not significant. Our results confirmed that health of RhD-positive heterozygotes and homozygotes differ. Therefore, any result of the comparison of subjects with RhD-positive and RhD-negative phenotype depends on the heterozygote-to-homozygote ratio in the RhD-positive sample. It is, therefore, crucial to analyze the effects of RHD-genotypes, not phenotypes in future studies.

[First experience with detecting bacterial DNA in the cerebrospinal fluid of patients with purulent meningitis using broad spectrum multiplex nested PCR]. / První zkusenosti s prukazem DNA bakterií v mozkomísním moku u pacientu s hnisavou pomocí sirokospektré multiplex nested PCR.

OBJECTIVES: To propose and verify a PCR assay for detecting Escherichia coli, Haemophilus influenzae, Listeria monocytogenes, Staphylococcus species, Streptococcus pneumoniae and Neisseria meningitidis serogroups B and C in a single sample of the cerebrospinal fluid of patients with purulent meningitis. MATERIAL AND METHODS: DNA from the cerebrospinal fluid was isolated using the QIAamp DNA Mini Kit. PCR was performed as two-step amplification (nested PCR). For E. coli, H. influenzae, L. monocytogenes, S. species and S. pneumoniae, universal and species-specific primers encoding bacterial 16S rDNA were used in the first and second reaction, respectively. For N. meningitidis serogroups B and C, an amplification system with primers for the SiaD gene was utilized. RESULTS: Of 25 patients examined at the beginning of their treatment, bacterial DNA was detected in the cerebrospinal fluid of 17 (68 %) of them. Those were six cases of N. meningitidis serogroup B, four of N. meningitidis serogroup C, five of S. pneumoniae, one of H. influenzae and one of L. monocytogenes. Of 7 patients in whom antibiotic therapy was initiated prior to diagnostic lumbar puncture, PCR was positive in four cases. CONCLUSIONS: The proposed nested PCR approach is faster than traditional culture methods and suitable for early laboratory diagnosis of infectious agents. When compared to culture methods, the technique offers slightly higher positivity (by 16 %). This is similar in samples analyzed after the initiation of antibiotic therapy. The PCR method never detected other bacteria than the cultured ones.

Diabetes mellitus in adults: association of HLA DRB1 and DQB1 diabetes risk alleles with GADab presence and C-peptide secretion.

In our study, we investigated the relationship of HLA class II alleles to antibody production against glutamic acid decarboxylase (GADab) and to C-peptide secretion (CP) in diabetic patients. A group of 334 patients (190 women) diagnosed after 35 years of age and 99 control subjects were studied. Patients were divided into four groups according to concentrations of CP and GADab, respectively (CP high/low, GADab positive/negative). HLA DQB1 and DRB1 alleles were genotyped by SSP-PCR. The significance of DQB1 and DRB1 risk alleles was evaluated by examination of their odds ratios computed by testing 2x2 tables considering Bonferonis' corrected P<0.05 as significant. We found strong association between the HLA DRB1*03 risk allele and presence of GADab, and close relationship of the HLA DRB1*04 and HLA DQB1*0302 risk alleles with decreased CP level. Taken together we conclude that the DRB1*04 and DQB1*0302 alleles are associated with progressive decrease of CP level, while DRB1*03 is a significant genetic marker of autoantibody (GADab) development.

[Detection of anti-Ehrlichia antibodies and direct demonstration of Ehrlichia nucleic acid using the polymerase chain reaction (PCR) in patients in the Czech Republic]. / Detekce antiehrlichiových protilátek a prímý prukaz ehrlichiové nukleové kyseliny polymerázovou retezovou reakcí (PCR) u pacientu v Ceské republice.

PURPOSE OF THE STUDY: In patients presenting symptoms with a suspicion of ehrlichiosis we determined antiehrlichia antibodies and investigated the presence of Ehrlichia nucleic acid in the plasma. MATERIAL AND METHODS: In our group were 46 patients with tick sucks in their case history, who presented symptoms compatible with ehrlichiosis. Anti-Ehrlichia antibodies were determined by an indirect immunofluorescent test with a commercial kit from MRL Diagnostics. Ehrlichia DNA was detected using a nested PCR - the target sequence was a part of the antigen Anaplasma phagocytophilum. RESULTS: Antibodies against HGE agents were demonstrated in 28 % of the patients; 10.5 % of the patients had in their serum antibodies reacting to the Ehrlichia chaffeensis antigen. The nucleic acid of A. phagocytophilum was detected in 11 % of the patients. CONCLUSIONS: The Czech population is relatively often exposed to Ehrlichia infections. Although most cases are asymptomatic, we should bear in mind this diagnosis, especially in immunodeficient patients, where early treatment may prevent a complicated course of the disease.