Comparative study of tissue culture and ELISA methods for cytomegalovirus infection diagnosis in abortions

Primary infection of cytomegalovirus especially in first and second trimester of pregnancy causes severe tissue injury and congenital abnormalities. Infection in third trimester of pregnancy has a higher chance of transmission but less tissue injury. Elisa method is a simple test for diagnosis of serum antibody but blood lymphocytes culture is a better and more specific diagnostic method than Elisa. In this study we compared Elisa and tissue culture methods for the diagnosis of congenital cytomegalovirus infections. In this study 5 ml of blood obtained from mothers who aborted their fetuses. Then serum antibody was titrated by ELISA method. Moreover, 5ml of citrated blood with 2 ml of Ficohl hypaque centrifuged in 3000 g and buffy coat layer of leukocytes was separated. These cells cultured in MRC5 fibroblast cell line and were assessed for intracellular inclusion bodies after 72 hours. Positive samples were selected and tested for nucleic acids of cytomegalovirus with PCR method. In this study, 118 cases of abortion were included. In tissue culture method, 6 samples [7.2%] had intracellular inclusion body. Of these samples only 4 had cytomegalovirus nucleic acid by PCR method. Two cases showed increasing anti-cytomegalovirus IgM with ELISA but they were negative by tissue culture method. In general, 6 cases [7.2%] of cytomegalovirus infection were diagnosed. ELISA and tissue culture methods should be performed together. Cytomegalovirus infection has not likely any relation with habitual abortion and is seen in first time abortions preferably

Autosomal recessive and sporadic non syndromic hearing loss and the incidence of Cx26 mutations in a Province of Iran

Despite the enormous heterogeneity of genetic hearing loss, mutations in the GJB2 [connexin 26] gene located on 'DFNB1' locus [13q12] account for up to 50% of cases of autosomal recessive non-syndromic hearing loss [ARNSHL] in some populations. This study describes the analysis of 100 autosomal recessive and sporadic nonsyndromic hearing loss individuals from 79 families each having at least one deaf child in Chehar Mahal va Bakhtiari province in west of Iran. We have investigated the prevalence of the connexin 26 gene mutations using nested PCR strategy to screen the predominant 35delG mutation and subsequent direct sequencing to detect other Cx26 mutations. Seven different genetic variants were detected from which one novel variant was including 363delC. The 35delG was the most common mutation found in 5 of 79 families [6.3%]. Cx26 related deafness mutations [35delG, [V27I; E114G]] and R127H] were found in 12 of 158 chromosomes studied [7.8%]. We conclude that the association of Cx26 mutations with deafness in Chehar Mahal va Bakhtiari province is low and looks like most other populations of Iran

[Surveying liver enzymes in workers exposed to vinyl chloride vapors]

Polyvinyl chloride [PVC] is used primarily to produce home appliances however, its production without vinyl chloride [VCM] is not reproducible. VCM has harmful effects on liver when is exposed during a long term duration. We surveyed long term liver effects with exposure of mild to moderate amounts of VCM. In this case-control study, liver enzymes levels of 52 workers were compared with 48 staff employees using t-test analysis. Case group was composed of all occupied workers in PVC production unit [one of the petrochemical complex], while, the control group was chosen form administrative staff of the same petrochemical complex. The mean level of alkaline phosphatase [ALP] and gamma glutamine trans peptidase [GGT] were shown to be significantly differed between the two groups. Other measures such as AST, ALT, and direct and indirect billirubin were revealed to be higher in case group, however, their difference did not reach a statistically significant level. Results revealed that exposure to even low levels of VCM may lead to mild liver cholestatic damage, therefore, use of tests for liver cholestasis such as GGT and ALP for individuals working in PVC production units should be kept in mind periodically

Frequencies of mutations in the connexin 26 gene [GJB2] in two populations of Iran [Tehran and Tabriz]

While hearing loss has been considered to be a very heterogeneous disorder, mutations in Gap junction beta 2 [GJB2] gene encoding Connexin 26 [Cx26] protein are the major cause of autosomal recessive and sporadic non-syndromic deafness in many populations. In this study, we have investigated the prevalence of the GJB2 gene mutations using nested PCR pre screening strategy and direct sequencing method. Two hundred and seventy two hearing impaired subjects were studied from 210 families obtained from two large cities of Iran [Tehran and Tabriz]. Twenty four different genetic variants were identified. Cx26 mutations were found in 53 of the 210 families [25.2%] including T8M, 35delG, W24X, R32H, V37I, E47X, 167delT, delE120, Y136X, R143W, R184P, 235delC and V27I+E114G. Homozygosity and compound heterozygosity for the Cx26 mutations were found in 39 of 210 [18.5%] families. Homozygosity for the 35delG mutation was the most common that causes hearing loss in 28 [13.3%] patients. Six novel variants H16R, E101E, K102Q, G200R, 327delG and G130A were detected in this study. As a conclusion, the present survey revealed that the rate of mutation in Cx26 gene in our area is lower than in Europe; nevertheless, this rate is regarded as a considerable cause of deafness in the cited provinces in Iran

Frequency of a very rare 35delG mutation in two ethnic groups of iranian population

The 35delG mutation in the Connexin 26 gene [Cx26], at the DNFB1 locus is the most common mutation in the patients with autosomal recessive non-syndromic hearing loss [ARNSHL]. We have studied a total of 224 deaf cases from 189 families in two populations of Iran [Sistan va Bluchestan and Hormozgan provinces] by prescreening nested PCR, polyacrylamide gel electrophoresis and consequent direct sequencing method for all cases. The aim of the present work was to find prevalence of GJB2 mutations in the populations studied. Four different GJB2 mutations including 35delG, W24X, R127H and [V27I + E114 G] were identified in 11 of 189 families [5.8%]. Two polymorphisms [V27I and V153I] also were detected in 14 families. A polymorphism S86T was determined in all cases. Homozygote 35delG mutation was found only in 1 of 189 families [0.5%].The rate of Cx26 mutations found in this study was lower than other Iranian populations. So the cause of deafness in the populations studied remains to be detected in other loci or genes