Targeted sequencing of DCSTAMP in familial Paget's disease of bone.

Paget's disease of bone (PDB) has a strong genetic component. Variants in SQSTM1 are found in up to 40% of patients with a family history of the disease, where a pattern of autosomal dominance with incomplete penetrance is apparent. By contrast, SQSTM1 variants are only found in up to 10% of patients with sporadic disease. It has been hypothesised that the remaining genetic susceptibility to PDB, particularly in familial cases, could be explained by rare genetic variants in loci previously identified by Genome Wide Association Studies. It is likely that polygenic factors are involved in many individuals. In this study we utilised whole exome sequencing to investigate predisposing genetic factors in an unsolved PDB kindred and identified a c.1189C > T p.L397F variant in DC-STAMP, also known as TM7SF4, that co-segregated with disease. DCSTAMP was identified as a gene of interest in PDB following Genome Wide Association Studies and has been previously shown to play critical roles in osteoclast fusion. The variant we identified has also been reported in association with PDB in a French-Canadian cohort however the significance of this variant was inconclusive. Targeted screening of DCSTAMP in our familial cohort of PDB patients revealed an additional 8 variants; however we did not find a significant association between any of these, including p.L397F, with PDB. Osteoclastogenesis assays from the affected proband and his unaffected brother demonstrated an increase in osteoclast number and nucleation, consistent with the pagetic phenotype. In converse to other established Paget's associated genetic variations such as SQSTM1, TNFRSF11A and OPTN, expression of the mutant DC-STAMP protein attenuated the activation of transcription factors NFκB and AP-1 when exogenously expressed. We found that the p.L397F variant did not influence the subcellular localization of the protein. Based on these findings we conclude that genetic variation in DCSTAMP is not a significant predisposing factor in our specific cohort of PDB patients and the p.L397F variant is unlikely to be a contributing factor in PDB pathogenesis.

Interaction between Hypertension and Asthma in Adult.

Asthma has been defined as a chronic inflammatory disorder of the airways that is associated with recruitment of inflammatory cells and the clinical development of wheezing, shortness of breath, chest tightness, and cough. The prevalence of asthma increased steadily over the latter part of the last century, first in the developed and then in the developing world. Current estimates suggest that asthma affects 300 million people worldwide, with a predicted additional 100 million people affected by 2025. This cross sectional study was conducted from January 1999 to August 1999 on 5642 Bangladeshi people and another same study carried out from November 2009 to April 2010 on 8088 subjects. In 1999 the prevalence of asthma was 6.9% whereas in 2010 it is 6.96%. Both asthma and hypertension are spastic disorders of smooth muscle, there is the similarities between these two diseases may predispose the individuals with one disease to the other. This descriptive type of cross-sectional study was done to find the Interaction between hypertension and asthma in adult and carried out in the Department of Physiology, Mymensingh Medical College, Mymensingh, Bangladesh from July 2014 to January 2016. Fifty (50) male and fifty (50) female adult asthmatic patients aged 18-60 years were included in the study group. They are enrolled from the Department of Medicine, Mymensingh Medical College, Mymensingh and also from locality. For comparison age matched 50 male and 50 female apparently healthy persons were also studied as control. Blood pressure was estimated by auscultatory method by sphygmomanometer. For statistical analysis unpaired student's 't' test was used. Mean blood pressure were significantly increased in study group in comparison to control group and the result was statistically significant (p<0.001). The study findings showed a high prevalence of hypertension among asthmatic patients than non asthmatic healthy persons. From this study, it may be concluded that hypertension and asthma are closely connected.

Cloning and expression of Bradyrhizobium japonicum uptake hydrogenase structural genes in Escherichia coli.

To identify the structural genes for the components of Bradyrhizobium japonicum uptake hydrogenase (Mr 60,000 and 30,000), we have expressed these genes in Escherichia coli and shown that the products cross-react with antibodies to the respective hydrogenase subunits. We constructed subclones of overlapping DNA fragments from an uptake hydrogenase-complementing cosmid, pHU52 [Lambert, G. R., Cantrell, M. A., Hanus, F. J., Russell, S. A., Haddad, K. R. & Evans, H. J. (1985) Proc. Natl. Acad. Sci. USA 82, 3232-3236], in pMZ 545, a plasmid expression vector. DNA fragments inserted into one or more of the four cloning sites downstream from the E. coli lac operon promoter (Plac) on pMZ 545 generate transcriptional, but not translational, fusions. Two subclones that directed the synthesis of Mr 60,000 and 30,000 proteins in E. coli "maxicells" were identified. The DNA inserts from these subclones were then inserted down-stream of the bacteriophage lambda PL promoter on a transcriptional fusion vector. When the PL promoter was activated in vivo by heat inactivation of the temperature sensitive cI repressor of lambda in an appropriate E. coli strain, the respective fragments expressed higher levels of Mr 60,000 and 30,000 proteins that could be detected in immunoblots. These data provide direct evidence for the presence of uptake hydrogenase structural genes on the uptake hydrogenase-complementing cosmid pHU52.