Novel SCN5A variants identified in a group of Iranian Brugada syndrome patients.

Brugada syndrome (BrS) is a rare hereditary arrhythmia syndrome that increases an individual's risk for sudden cardiac death (SCD) due to ventricular fibrillation. This disorder is regarded as a notable cause of death in individuals aged less than 40 years, responsible for up to 40% of sudden deaths in cases without structural heart disease, and is reported to be an endemic in Asian countries. Mutations in SCN5A are found in approximately 30% of patients with Brugada syndrome. This study aimed to investigate mutations in the SCN5A gene in a group of Iranian Brugada syndrome patients. Nine probands (n = 9, male, mean age = 39) diagnosed with Brugada syndrome were enrolled in this study. Exon 2 to 29 were amplified by PCR and subjected to direct sequencing. Eight in silico prediction tools were used to anticipate the effects of non-synonymous variants. Seven known polymorphisms and 2 previously reported disease-causing mutations, including H558R and G1406R, were found in the studied cases. Twenty novel variants were identified: 15 missense, 2 frameshift, 2 synonymous, and one nonsense variants. In silico tools predicted 11 non-synonymous variants to have damaging effects, whereas frameshift and nonsense variants were considered inherently pathogenic. The novel variants identified in this study, alongside previously reported mutations, are highly likely to be the cause of the Brugada syndrome phenotype observed in the patient group. Further analysis is required to understand the physiological effects caused by these variants.

Association between Cryptosporidium infection and cancer: A systematic review and meta-analysis.

The link between cryptosporidiosis and cancer has been suggested by some epidemiological studies. This systematic review and meta-analysis was conducted to further understand this relationship. In the current study, six electronic databases were reviewed for Cryptosporidium infection in cancer patients. We used random effects model and 95% confidence intervals (CI) to determine the overall odds ratio (OR). Heterogeneity was calculated with Cochran's Q test and I2statistic. In total, 19 studies involving 3562 individuals with case-control (nine) and cross-sectional (ten) designs were included in our project. The pooled overall random effect favored a statistically significant increased risk of Cryptosporidium infection in cancer patients compared with non-cancer individuals [OR = 3.3; 95% CI: 2.18-4.98]. The overall heterogeneity was medium (χ2 = 25.77; I2 = 30.2%, P = .11). The pooled ORs in case-control and cross-sectional studies were [OR = 5.60; 95% CI: 3.43-9.13; χ2 = 5.51; I2 = 0.00%, P = .70] and [OR = 2.08; 95% CI: 1.18-3.67; χ2 = 13.69; I2 = 34.3, P = .13], respectively. T-value and P-value were 0.54 and 0.57 based on the results of Harbord's modified's regression test. In summary, this meta-analysis demonstrates that Cryptosporidium infection is associated with cancer. Also, it found that study design and year of publication are the specific sources of heterogeneity. Further studies should be carried out to investigate the impact of Cryptosporidium infection in the onset or development of cancer in the future.

Detection of Toxoplasma gondii DNA in Malignant Breast Tissues in Breast Cancer Patients.

Breast cancer is the most prevalent malignancy in women throughout the world. Similar to other cancers, a strong relationship between breast cancer and environmental factors such as infectious agents has been reported. Toxoplasma gondii is a protozoan parasite which may play a role in cancer induction. The present study aimed to investigate a possible association between a history of T. gondii infection and breast cancer by detecting T. gondii DNA in malignant and non-malignant breast and lymph nodes tissues from breast cancer patients with latent toxoplasmosis. Formalin-fixed, paraffin-embedded (FFPE) tissue blocks from malignant/non-malignant breast and lymph nodes were obtained from twenty-nine breast cancer patients who were positive for anti-Toxoplasma antibodies (IgG). FFPE tissue blocks were deparaffinized using hot water method, and DNA was extracted. A conventional PCR analysis was performed to amplify partial regions of T. gondii B1 and REP-529 genes. Ninety-three samples from 29 patients were examined. All patients were negative for anti-T. gondii antibodies (IgM). T. gondii DNA was detected in 3 (10.3%) patients by PCR analysis of either B1 or REP-529 genes. These include two malignant breast and one normal lymph node samples. Sequence analysis of these genes showed a good similarity with previously published B1 and REP-529 sequences of T. gondii in NCBI GenBank. This study did not find any association between T. gondii infection and breast cancer. Furthermore, it is the first molecular identification of T. gondii in FFPE tissue samples obtained from breast cancer patients.

Deparaffinization of formalin-fixed paraffin-embedded tissue blocks using hot water instead of xylene.

This study aimed to deparaffinize formalin-fixed paraffin-embedded (FFPE) tissues using hot water instead of xylene and measuring the quantity and quality of the extracted DNA from the respective tissues. To deparaffinize the tissue sections with hot water, small sections were exposed to 90 °C distilled sterile water. After 25 FFPE tissue samples were deparaffinized with the hot water method, DNA was then extracted. The mean of optical density and the ratio of absorbance of the DNA solution were 220.01 ± 36.1 ng/µl and 1.65 ± 0.1, respectively. Polymerase chain reaction (PCR) analysis of the toll-like receptor 4(TLR4) gene showed that the method can be used as a tool for different applications.