Zabun Nahar

Loss of the proprioception and touch sensation channel PIEZO2 in siblings with a progressive form of contractures

Dominant mutations in PIEZO2, which codes for the principal mechanotransduction channel for proprioception and touch sensation, have been found to cause different forms of distal arthrogryposis. Some observations suggest that these dominant mutations induce a gain‐of‐function effect on the channel. Here, we report a consanguineous family with three siblings who showed short stature, scoliosis, gross motor impairment, and a progressive form of contractures involving the distal joints that is distinct from that found in patients with dominant mutations in PIEZO2. These siblings also displayed deficits in proprioception and touch sensation. Whole‐exome sequencing performed in the three affected siblings revealed the presence of a rare homozygous variant (c.2708C>G; p.S903*) in PIEZO2. This variant is predicted to disrupt PIEZO2 function by abolishing the pore domain. Sanger sequencing confirmed that all three siblings are homozygous whereas their parents and an unaffected sibling are heterozygous for this variant. Recessive mutations in PIEZO2 thus appear to cause a progressive phenotype that overlaps with, while being mostly distinct from that associated with dominant mutations in the same gene.

Determination of Serum Antioxidant Vitamins, Glutathione and MDA Levels in Panic Disorder Patients

There are sufficient experimental evidences to establish the relationship between the elevated level of malondealdehyde (MDA)-the lipid peroxidation product and depleted level of antioxidants (Vitamin A, E, C and glutathione) in several psychiatric disorders. But previously no study was carried out to determine these components in panic disorder (PD) patients of Bangladesh. This study was conducted to assess the serum concentration of antioxidant vitamins, MDA and glutathione in 54 panic disorder patients and 52 healthy volunteers. Patients were recruited from Bangabandhu Sheikh Mujib Medical University, Bangladesh by random sampling. Serum level of MDA, glutathione and vitamin C were determined by UV spectrophotometric method whereas Vitamins A and E were detected by RP-HPLC method. Data were analyzed by independent t test and Pearsons correlation analysis. It had been found that the PD patients had low level of antioxidants like vitamin A (p=0.041) and vitamin E (p=0.018) than the healthy controls whereas the change of vitamin C is not significant. It had been found that the MDA content was significantly higher (p<0.05) in PD patients than that of controls. There was no significant difference for the glutathione content between the 2 groups. Pearsons correlation coefficient suggested that there were significant negative correlation between the glutathione level and vitamin C (p=0.013) and a positive correlation between the vitamin E and vitamin A (p=0.020) in patient group. Our study reveals that panic disorder patients have considerably higher level of MDA, lower level of antioxidant vitamins and glutathione than the healthy control subjects.

Association of TP53 codon 72 and CDH1 genetic polymorphisms with colorectal cancer risk in Bangladeshi population

Till now no pharmacogenetic study of TP53 codon 72 (Arg72Pro) and CDH1 rs16260 (-160C<A) genes has been reported on Bangladeshi population relating those with colorectal cancer. So the aim of the study is to determine whether there is an elevated risk of colorectal cancer development with TP53 codon 72 and CDH1 rs16260 genetic polymorphism in Bangladeshi population for the first time. To investigate the association of these two SNPs, we conducted a case-control study with 288 colorectal cancer patients and 295 healthy volunteers by using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) method. We found an increased risk of association between Arg/Pro heterozygosity (adjusted OR=2.58, 95% CI=1.77-3.77, p<0.05) and Pro/Pro mutant homozygosity (adjusted OR=2.92, 95% CI=1.78-4.78, p<0.05) along with the combined genotype (Arg/Pro+Pro/Pro) (adjusted OR=2.70, 95% CI=1.90-3.82, p<0.05) and colorectal cancer predisposition. In case of CDH1 rs16260 polymorphism, C/A heterozygous and A/A mutant homozygous are significantly (p<0.05) found to be associated with colorectal cancer risk with adjusted OR of 1.94 and 2.63, respectively. The combined genotype of C/A and A/A was also found to be strongly associated with colorectal cancer risk compared to C/C genotype (adjusted OR=2.02, 95% CI=1.42-2.87, p<0.05). In conclusion, heterozygosity and mutant homozygosity as well as the combination of both TP53 Arg72Pro and CDH1 rs16260 polymorphisms are responsible to increase the risk of colorectal cancer development in Bangladeshi population.

Comparative analysis of serum malondialdehyde, antioxidant vitamins and immunoglobulin levels in patients suffering from generalized anxiety disorder.

The relationship between the elevated levels of serum malondialdehyde, depleted level of antioxidants (vitamin A, E and C) and altered level of immunoglobulins (IgA, IgG and IgM) in several psychiatric disorders has been established by various experimental evidences over the past few years. But previously no study was carried out to determine these components in patients suffering from generalized anxiety disorder (GAD) in Bangladesh. This study was conducted to compare the serum concentration of these components in GAD patients and healthy volunteers; matched by socioeconomic and sociodemographic parameters. Serum level of malondialdehyde and vitamin C were determined by UV spectrophotometric method, vitamins A and E were detected by RP-HPLC method whereas immunoglobulin levels were determined by turbidimetric method. Data were analyzed by independent t-test, Pearsons correlation and regression analysis. Significantly lower level of vitamin E (p<0.05) and significantly higher level of vitamin C were found in GAD patients than the healthy controls, whereas the change of vitamin A was insignificant. Serum malondialdehyde content was significantly higher (p<0.05) and IgM level was significantly (p<0.05) higher than that of the controls. Change in concentrations of IgG and IgA were insignificant (p>0.05). Pearsons correlation coefficient suggested that there were some significant positive and negative correlations among these tested components. Our study reveals that GAD patients have considerably higher level of malondialdehyde, immunoglobulins and altered level of antioxidant vitamins. These findings may play a key role in the diagnosis and treatment of GAD patients.

Elevated serum levels of malondialdehyde and cortisol are associated with major depressive disorder: A case-control study

Objectives: Major depressive disorder is diagnosed on the basis of patient’s self-reported experiences, behavior reported by relatives, and a mental status examination, and yet we do not have any reliable biomarker for this. Mood-regulating pathways are affected by oxidative injury to lipids and cortisol is released into the blood due to stimulation of corticotrophin receptors in the adrenal cortex. Here, we aimed to determine serum levels of malondialdehyde and cortisol in major depressive disorder patients and controls. Methods: We collected blood samples from 247 major depressive disorder patients and 248 controls. Serum levels of malondialdehyde and cortisol were measured by ultraviolet spectrophotometry and enzyme-linked immunosorbent assay kit, respectively. Results: We found malondialdehyde levels were significantly higher in patients than controls, with mean ± standard deviation at 4.49 ± 1.37 and 2.87 ± 0.82 µmol/L, respectively, p < 0.001. Cortisol levels were also found significantly higher in patients than controls, with mean ± SD at 19.22 ± 1.64 and 17.37 ± 1.34 µg/dL, respectively, p < 0.001. Significant negative correlation was observed between serum levels of malondialdehyde and cortisol in patients (r =−0.170, p = 0.021). Receiver operating characteristic analysis showed good diagnostic value for malondialdehyde and cortisol, with the area under the curve at 0.853 and 0.819, respectively. Conclusion: The present study suggests that increased serum levels of malondialdehyde and cortisol are strongly associated with major depressive disorder. We believe elevations of malondialdehyde and cortisol in serum level arise independently and they could serve as biomarkers for major depressive disorder.

DPYD*2A and MTHFR C677T predict toxicity and efficacy, respectively, in patients on chemotherapy with 5-fluorouracil for colorectal cancer

BackgroundSignificant inter-individual variation in the sensitivity to 5-fluorouracil (5-FU) represents a major therapeutic hindrance either by impairing drug response or inducing adverse drug reactions (ADRs). This study aimed at exploring the cause behind this inter-individual alterations in consequences of 5-fluorouracil-based chemotherapy by investigating the effects of DPYD*2A and MTHFR C677T polymorphisms on toxicity and response of 5-FU in Bangladeshi colorectal cancer patients.MethodsColorectal cancer patients (n = 161) receiving 5-FU-based chemotherapy were prospectively enrolled. DPYD and MTHFR polymorphisms were assessed in peripheral leukocytes. Multivariate analyses were applied to evaluate which variables could predict chemotherapy-induced toxicity and efficacy.ResultsMultivariate analyses showed that DPYD*2A polymorphism was a predictive factor (P = 0.023) for grade 3 and grade 4 5-fluorouracil-related toxicities. Although MTHFR C677T polymorphism might act as forecasters for grade 3 or grade 4 neutropenia, diarrhea, and mucositis, this polymorphism was found to increase significantly (P = 0.006) the response of 5-FU.ConclusionDPYD*2A and MTHFR C677T polymorphisms could explain 5-FU toxicity or clinical outcome in Bangladeshi colorectal patients.

Genetic variants of SULT1A1 and XRCC1 genes and risk of lung cancer in Bangladeshi population

Lung cancer is one of the most frequently occurring cancers throughout the world as well as in Bangladesh. This study aimed to correlate the prognostic and/or predictive value of functional polymorphisms in SULT1A1 (rs9282861) and XRCC1 (rs25487) genes and lung cancer risk in Bangladeshi population. A case-control study was conducted which comprises 202 lung cancer patients and 242 healthy volunteers taking into account the age, sex, and smoking status. After isolation of genomic DNA, genotyping was done by polymerase chain reaction–restriction fragment length polymorphism method and the lung cancer risk was evaluated as odds ratio that was adjusted for age, sex, and smoking status. A significant association was found between SULT1A1 rs9282861 and XRCC1 rs25487 polymorphisms and lung cancer risk. In case of rs9282861 polymorphism, Arg/His (adjusted odds ratio = 5.06, 95% confidence interval = 3.05–8.41, p < 0.05) and His/His (adjusted odds ratio = 3.88, 95% confidence interval = 2.20–6.82, p < 0.05) genotypes were strongly associated with increased risk of lung cancer in comparison to the Arg/Arg genotype. In case of rs25487 polymorphism, Arg/Gln heterozygote (adjusted odds ratio = 4.57, 95% confidence interval = 2.79–7.46, p < 0.05) and Gln/Gln mutant homozygote (adjusted odds ratio = 4.99, 95% confidence interval = 2.66–9.36, p < 0.05) were also found to be significantly associated with increased risk of lung cancer. This study demonstrates that the presence of His allele and Gln allele in case of SULT1A1 rs9282861 and XRCC1 rs25487, respectively, involve in lung cancer prognosis in Bangladeshi population.