Association between ABO and Rh blood groups and Toxoplasma gondii infection: A cross sectional study.

We aimed to determine the association between the seropositivity to Toxoplasma gondii and the ABO and Rh blood groups in 2,053 people. ABO and Rhesus blood groups and anti-T. gondii IgG and IgM antibodies were determined using commercially available assays. Of the 2,053 people studied, 171 (8.3%) were positive for anti-T. gondii IgG antibodies. Sixty-five (38.0%) and 36 (21.1%) of these 171 individuals had high anti-T. gondii IgG antibody levels (≥150 IU mL-1) and anti-T. gondii IgM antibodies, respectively. We found the following prevalences of T. gondii infection among the ABO groups: 8.5% in group A, 4.3% in group B, 4.7% in group AB, and 8.9% in group O (P = 0.19). The prevalences of T. gondii infection among Rh groups were: 8.4% in the Rh-positive group and 7.1% in the Rh-negative group (P = 0.58). Logistic regression analysis showed that the frequencies of ABO and Rh blood groups were similar (P > 0.05) among people with positive and negative serology for anti-T. gondii IgG antibodies, with high (≥150 IU mL-1) and lower (<150 IU mL-1) levels of anti-T. gondii IgG antibodies, and with positive and negative serology for anti-T. gondii IgM antibodies. Results does not support an association between T. gondii infection and ABO and Rh blood groups.

Prevalence of Chlamydia trachomatis Infection Diagnosed by Polymerase Chain Reaction in Female Sex Workers in a Northern Mexican City.

PURPOSE: We aimed to determine the association between Chlamydia trachomatis infection and female sex work, and the association between sociodemographic, obstetric, and behavioral characteristics of female sex workers and C. trachomatis infection. METHODS: Through a case-control study design, we studied 201 female sex workers and 201 age-matched women without sex work in Durango City, Mexico. C. trachomatis DNA was detected in cervical swab samples using polymerase chain reaction. RESULTS: C. trachomatis DNA was detected in 32 (15.9%) of the 201 cases and in 6 (3.0%) of the 201 controls (odds ratio [OR] = 6.15; 95% confidence interval [CI]: 2.5-15.0; P < 0.001). The frequency of infection with C. trachomatis in female sex workers did not vary (P > 0.05) regardless of the history of pregnancies, deliveries, cesarean sections, or miscarriages. Regression analysis of the behavioral characteristics showed that infection with C. trachomatis was associated only with consumption of alcohol (OR = 2.39; 95% CI: 1.0-5.71; P = 0.04). Conclusions: We conclude that C. trachomatis infection is associated with female sex work in Durango City, Mexico. This is the first age-matched case-control study on the prevalence of C. trachomatis infection in female sex workers in Mexico using detection of C. trachomatis DNA in cervical samples.

Human Papillomavirus Infection in Female Sex Workers: A Case Control Study.

BACKGROUND: To determine the association of infection with human papillomavirus (HPV) and the occupation of female sex worker; and the correlation of infection with HPV with sociodemographic, clinical and behavioral characteristics of female sex workers. METHODS: We performed a case-control study of 217 female sex workers and 354 women without sex work in Durango City, Mexico. We determined the prevalence of infection with HPV in cervical samples of women using polymerase chain reaction, and HPV genotypes were determined using line probe assay. Bivariate and multivariate analyses were used to assess the association between the characteristics of women and infection. RESULTS: Twelve (5.5%) of the 217 sex workers, and 10 (2.8%) of the 354 control women were positive for HPV DNA (age-adjusted OR = 1.51; 95% CI: 0.62 - 3.68; P = 0.36). Six (50.0%) of the 12 HPV DNA positive sex workers had infections with high-risk genotypes (16, 31, 33, 35, 51, 58). Seven (70%) of the 10 HPV DNA positive control women had infections with high-risk genotypes (16, 18, 56, 58, and 66). The frequency of high risk genotypes in the control women was equal with that found in the female sex workers (P = 0.41). Logistic regression analysis showed that the variable alcohol consumption was associated with HPV infection (OR = 4.0; 95% CI: 1.0 - 16.0; P = 0.04). CONCLUSIONS: No association between HPV infection and female sex work was found in our setting. High risk HPV genotypes were prevalent among the women studied. Results can be used for the design of preventive measures against HPV infection.

Lack of Association between Mannose-binding Lectin 2 Codons 54 and 57 Gene Polymorphisms and Cervicovaginal Infections in Mexican Women.

The mannose-binding lectin (MBL) 2 gene has an important function in the innate immune response and activation of the third pathway of the complement system. Some studies have assessed the association of the MBL2 gene polymorphisms with cervicovaginal infections (CVI); however, there is no information about this association in Mexican women. This study aimed to determine the association between the MBL2 codons 54 and 57 gene polymorphisms with CVI in a sample of Mexican women. Through a cross-sectional study, blood samples and cervicovaginal cultures were obtain from 354 women. MBL2 genotyping was performed by real-time polymerase chain reaction with Taqman probes. Of the 354 women studied, 128 (36.2%) had CVI and 226 (63.8%) were healthy. The frequencies of the C and T variants in codon 54 in women with CVI were 83% and 17%, respectively; whereas the frequencies of these variants in healthy women were 82% and 18%, respectively. The frequencies of variants C/C, C/T, and T/T in women with CVI were 68%, 31%, and 1%, respectively; whereas the frequencies of these variants in healthy women were 68%, 29%, and 3%, respectively. With respect to codon 57, the frequencies of variants C and T were identical in women with CVI and in healthy women (97% and 3%, respectively). The frequencies of variants C/C, C/T, and T/T were identical in women with CVI and in healthy women (94%, 6%, and 0%, respectively). We conclude that MBL2 codons 54 and 57 gene polymorphisms do not associate with CVI in Mexican women.

Oxidative stress equilibrium during obstetric event in normal pregnancy.

OBJECTIVE: The aim of this study was to determine malondialdehyde (MDA) concentration as an oxidative stress marker and total antioxidant capacity (TAC) in pregnancy before and after perinatal event. METHODS: This study was performed on 200 healthy full-term pregnant women admitted to pregnancy resolution in Maternal-Child Hospital of Durango, Mexico. Oxidative stress and TAC were assessed through detection of lipid peroxidation by quantitation of thiobarbituric acid-reactive substances (TBARS) and TAC through ferric reducing ability of the plasma (FRAP). RESULTS: Our results showed increased levels of MDA after vaginal delivery (VD). TAC was also increased after obstetric event, but it did not differ between VD and caesarean section. CONCLUSIONS: We demonstrated that MDA concentrations are increased two hours after obstetric event, and this increase correlates with VD. The TAC was increased as a compensatory mechanism during obstetric event. Another important finding is that women receiving analgesia administration in VD, as well as dexamethasone administration in caesarean section, experienced a protector effect that decreased MDA levels.

Arsenic exposure and risk of preeclampsia in a Mexican mestizo population.

BACKGROUND: Exposure to arsenic in drinking water has been associated with various complications of pregnancy including fetal loss, low birth weight, anemia, gestational diabetes and spontaneous abortion. However, to date, there are no studies evaluating its possible association with preeclampsia. METHODS: This case-control study involved 104 preeclamptic and 202 healthy pregnant women. The concentrations of arsenic in drinking water and urine were measured using a Microwave Plasma-Atomic Emission Spectrometer. RESULTS: We found relatively low levels of arsenic in household tap water (range of 2.48-76.02 µg/L) and in the urine of the participants (7.1 µg/L vs 6.78 µg/L in cases and controls, respectively). CONCLUSIONS: The analysis between groups showed for the first time that at these lower levels of exposure there is no association with preeclampsia.

Relationship between blood lead levels and hematological indices in pregnant women.

Several studies have revealed a negative association between blood lead levels and hematological impairment. In this cross-sectional study, we examined the relationship between blood lead levels and hematological indices in 292 pregnant women from Durango, Mexico. Apparently healthy pregnant women, aged 14-41 years and at 3-41 weeks of gestation, were recruited between June 2007 and May 2008. Blood lead and hematological indices were measured. The mean blood lead was 2.79 ± 2.16 µg/dL, and lead levels ≥ 5 µg/dL were detected in 25 women (8.6%). Hemoglobin, hematocrit, and red blood cells count were significantly higher in pregnant women with a blood lead concentration of ≥ 5 µg/dL than the group with lower blood lead levels (p < .05). Mean corpuscular volume and mean corpuscular hemoglobin were not significantly related to lead levels. Hemoglobin and hematocrit showed a non-significant positive correlation with blood lead, but the correlation between red blood cell count and blood lead levels was statistically significant (r = 0.185, p = .002). The findings suggest that a positive association between blood lead and some hematological indices may occur at relatively low blood lead concentration (mean < 5 µg/dL).

Polymorphisms in DNA repair genes (APEX1, XPD, XRCC1 and XRCC3) and risk of preeclampsia in a Mexican mestizo population.

Variations in genes involved in DNA repair systems have been proposed as risk factors for the development of preeclampsia (PE). We conducted a case-control study to investigate the association of Human apurinic/apyrimidinic (AP) endonuclease (APEX1) Asp148Glu (rs1130409), Xeroderma Pigmentosum group D (XPD) Lys751Gln (rs13181), X-ray repair cross-complementing group 1 (XRCC) Arg399Gln (rs25487) and X-ray repair cross-complementing group 3 (XRCC3) Thr241Met (rs861539) polymorphisms with PE in a Mexican population. Samples of 202 cases and 350 controls were genotyped using RTPCR. Association analyses based on a χ2 test and binary logistic regression were performed to determine the odds ratio (OR) and a 95% confidence interval (95% CI) for each polymorphism. The allelic frequencies of APEX1 Asp148Glu polymorphism showed statistical significant differences between preeclamptic and normal women (p = 0.036). Although neither of the polymorphisms proved to be a risk factor for the disease, the APEX1 Asp148Glu polymorphism showed a tendency of association (OR: 1.74, 95% CI = 0.96-3.14) and a significant trend (p for trend = 0.048). A subgroup analyses revealed differences in the allelic frequencies of APEX1 Asp148Glu polymorphism between women with mild preeclampsia and severe preeclampsia (p = 0.035). In conclusion, our results reveal no association between XPD Lys751Gln, XRCC Arg399Gln and XRCC3 Thr241Met polymorphisms and the risk of PE in a Mexican mestizo population; however, the results in the APEX1 Asp148Glu polymorphism suggest the need for future studies using a larger sample size.

Haplotype analysis of TGF-ß1 gene in a preeclamptic population of northern Mexico.

OBJECTIVE: To determine the frequencies of -800G/A (rs1800468), -509C/T (rs1800469) and 869T/C (rs1800470) polymorphisms and their haplotypes in the TGF-ß1 gene and their association with preeclampsia in a population of northern México. DESIGN AND METHODS: This case-control study involved 175 preeclamptic and 253 normoevolutive pregnant women. The polymorphisms were genotyped by real time PCR. RESULTS: The allele and genotype frequencies of polymorphisms showed no significant differences between cases and controls; the -800AA genotype had a very low frequency in cases (1%) and controls (0.4%). The TT genotype of the 869T/C polymorphism is a protective factor of severe preeclampsia (OR 0.56, 95% CI 0.32-0.98). The -509C/T and 869T/C polymorphisms were in linkage disequilibrium (D'=.537, p=.009). The most common haplotypes in case and control groups were -800G/-509C/869C, 34.95% and 37.24%, respectively. We found no increased risk of preeclampsia by haplotype. CONCLUSIONS: Our results suggest that -800G/A, -509C/T and 869T/C polymorphisms of TGF-ß1 gene or their haplotypes are not associated with preeclampsia and that only the TT genotype of 869T/C polymorphism is a protective factor of severe preeclampsia in a population of northern México.

Association of COMT G675A and MTHFR C677T polymorphisms with hypertensive disorders of pregnancy in Mexican mestizo population.

OBJECTIVE: To investigate the relationship between COMT G675A and MTHFR C677T polymorphisms and hypertension disorders of pregnancy (HDP) in a Mexican mestizo population. DESIGN AND METHODS: This case-control study involved 194 HDP and 194 normoevolutive pregnant women. The polymorphisms were genotyped by real time PCR. RESULTS: Our results showed that the COMT AA genotype increases the risk to HDP (OR: 2.67; 95% CI 1.33-5.35), preeclampsia (OR: 2.69; 95% CI 1.00-7.22) and gestational hypertension (OR: 3.87; 95% CI 1.25-12.0). Furthermore, the double mutant genotype (COMTAA/MTHFRTT) potency the risk to HDP more than two times (OR: 5.21; 95% CI 1.12-24.3, p=0.019). CONCLUSION: Our work provides evidence that COMT 675AA genotype is a risk factor for HDP and that this risk is increased by the presence of MTHFR 677TT genotype in a Mexican mestizo population.

Genesis of preeclampsia: an epidemiological approach.

THERE ARE ANALYZED SOME OF THE MAIN ASPECTS RELATED TO THE CAUSALITY OF PREECLAMPSIA, PRIVILEGING TWO TYPES OF MODELS: the clinic model and the epidemiologic model, first one represented by the hypothesis of the reduced placental perfusion and the second one considering the epidemiologic findings related to the high levels of psychosocial stress and its association with preeclampsia. It is reasoned out the relevance of raising the causality of the disease from an interdisciplinary perspective, integrating the valuable information generated from both types, clinical and epidemiologic, and finally a tentative explanatory model of preeclampsia is proposed, the subclinical and sociocultural aspects that predispose and trigger the disease are emphasized making aspects to stand out: the importance of reduced placental perfusion as an indicator of individual risk, and the high levels of physiological stress, as a result of the unfavorable conditions of the psychosocial surroundings (indicator of population risk) of the pregnant women.

Niveles de cortisol salivario como predictor de preeclampsia en adolescentes / Salivary cortisol levels as a predictor of preeclampsia in adolescentes

Objective: To determine the usefulness of salivary cortisol as a predictor of preeclampsia in adolescents.Methods: We carried out a nested case- control study. Somatometric, clinical, and biochemical data were obtainedfrom 100 healthy pregnant adolescents and salivary cortisol was measured at 8:00, 12:00, and 20:00 hours on twooccasions during pregnancy, before 20 weeks, and after 30 weeks of gestation. The cortisol values between the groupof healthy pregnant women and the group that developed preeclampsia were compared by using the Student’s t, Mann-Whitney, and Wilcoxon tests. Also, the ROC curve of cortisol values and the Positive and Negative Predictive values of cortisol were estimated. Results: Values >14.9 nmol/L of cortisol were observed in the group that developed preeclampsia, providing a positive predictive value of 1 (100%). Values <10.1 nmol/L were observed in the control group, the negative predictive value was 1 (100%). The cutoff point of the ROC curve -before 20 weeks of gestation- in the members of the cohort was 13.9 nmol/L. Conclusions: The salivary cortisol values observed in the two evaluations made to each of the groups showed statistically significant differences between the groups at 8 and 12 hours of the day. The values obtained enable establishing gradients that allow separating the group of healthy women that got ill with preeclampsia from the groupthat did not develop the illness before week 20. After week 30, the cortisol gradients are established more clearly inthe group with preeclampsia and in the control group. The validation of these findings in larger samples would allowimplementing this procedure as a screening test for preeclampsia in groups of pregnant adolescents.