BRCA1-methylated sporadic breast cancers are BRCA-like in showing a basal phenotype and absence of ER expression

BRCA1 mutations have been associated with hereditary breast cancer only. Recent studies indicate that a subgroup of sporadic breast cancer might also be associated with reduction in BRCA1 mRNA levels and protein expression. However, the mechanism of reduced mRNA and protein expression is yet not fully elucidated. This study aims to assess BRCA1 protein expression and the role of BRCA1 promoter methylation in sporadic breast cancer in North Indian population and to correlate these with known prognostic factors and molecular profiles of breast cancer. BRCA1 protein expression was normal (>50?% tumour cells) in 41 (43?%) cases, reduced (20-50?% tumour cells) in 33 (35?%) cases and absent/markedly reduced (<20?% tumour cells) in 21 (22.1?%) cases. Cases which were negative for BRCA1 protein were more frequently positive for basal markers (29 versus 5?%) and were more often ER-negative (62 versus 39?%) than BRCA1-positive tumours. Methylation of BRCA1 promoter region was seen in 11/45 cases (24?%). All 11 cases showing BRCA1 methylation had absent (eight cases) or reduced (three cases) BRCA1 protein expression. BRCA1 protein-negative tumours were more frequently basal marker-positive and ER-negative, highlighting the 'BRCAness' of sporadic breast cancer with loss of BRCA1 protein expression through promoter hypermethylation similar to hereditary breast cancer with BRCA1 mutations. Loss of BRCA1 in sporadic breast cancer suggests that therapeutics targeting BRCA1 pathway in hereditary breast cancer like PARP inhibitors might be used as therapeutic targets for sporadic breast tumours.     

In-vitro metabolic inhibition and antifertility effect facilitated by membrane alteration: search for novel antifertility agent using nifedipine analogues

In search of non-hormonal male contraceptives, analogues of nifedipine, which causes reversible infertility, have been synthesized and their interaction at molecular level with model membrane has been probed. Analogues act differently with respect to their antifertility action. This is achieved by altering the cell metabolism thereby directly affecting the motility which is responsible for fertility. Secondly, these drugs bind differently to the interior of the cell-membrane affecting the membrane fluidity, architecture and dynamics. Sulfasalazine and D₄ interact to a larger extent and alter the lipid bilayer phase to a hexagonal. D₁, D₂ and D₃ do not have considerable effect. D₄ is the most promising candidate as a lead compound for the development of novel non-hormonal male antifertility agents.     

Synthesis, characterization and pharmacological activity of 4-{[1-substituted aminomethyl-4-arylideneamino-5-sulfanyl-4,5-dihydro-1H-1,2,4-triazol-3-yl]methyl}-2H-1,4-benzothiazin-3(4H)-ones

A new series of Schiff and Mannich bases derivatives (6) of 4-[(4-amino-5-sulfanyl-4H-1,2,4-triazol-3-yl)methyl]-2H-1,4-benzothiazin-3(4H)-one (4), derived from (3-oxo-2,3-dihydro-4H-1,4-benzothiazin-4-yl)acetic acid (3) were synthesized. The structures of all newly synthesized compounds were elucidated by elemental analysis, IR, ¹H NMR and mass spectral data. Synthesized compounds were evaluated for their anti-inflammatory and analgesic activity. Among the tested compounds, the (3-oxo-2,3-dihydro-4H-1,4-benzothiazin-4-yl)acetic acid (3) possess analgesic activity comparable to that of pentazocine; activity decreased on derivatization of the carboxylic acid group. However the anti-inflammatory activity of (3-oxo-2,3-dihydro-4H-1,4-benzothiazin-4-yl)acetic acid (3) increased by derivatization of the carboxylic acid group and some of the compounds showed anti-inflammatory activity comparable to that of indomethacin.     

Cell-free sorting of peroxisomal membrane proteins from the endoplasmic reticulum

Several yeast and mammalian peroxisomal membrane proteins (PMPs) are delivered to peroxisomes via the endoplasmic reticulum (ER). Fluorescence microscopy showed a focused assembly of PMPs in a specialized domain of the ER, referred to as the preperoxisomal ER. It is proposed that preperoxisomal vesicles containing PMPs bud from this domain to either fuse with preexisting peroxisomes or to mature into functional peroxisomes by uptake of peroxisomal membrane and matrix proteins. However, such vesicular entities are not identified nor are the biochemical requirements for the budding process known. We developed an in vitro cell-free ER-budding assay using Pichia pastoris and followed two endogenous PMPs, Pex11p and Pex3p during their ER exit. Both the PMPs were copackaged in the ER-budded vesicles that float on a Nycodenz gradient. PMP budding from the ER was dependent on ATP, temperature, cytosol, and Pex19p and generated preperoxisomal vesicles with an incomplete complement of PMPs. Surprisingly, Pex11p budding was independent of Pex3p; however, the budded vesicles were devoid of most of the PMPs otherwise present in the wild-type vesicles and might represent peroxisomal remnants. Our findings provide a biochemical platform to uncover the mechanism of PMP budding from the ER.     

Pulmonary rehabilitation in resource poor settings

Pulmonary rehabilitation is an important component in the management of chronic obstructive pulmonary disease (COPD) and other chronic respiratory diseases. The goal of rehabilitation is to evaluate various systems, treat optimally, improve dyspnoea and health-related quality of life. It is a multi-disciplinary approach and involves a physician, a psychiatrist, a dietician and a physiotherapist. However, in a resource-poor setting, even an experienced physician alone may suffice. Exercise training is the backbone of pulmonary rehabilitation, which may be hospital-based or home-based. Though, the previous trials have shown benefit with hospital-based rehabilitation, several recent studies have demonstrated significant improvement in the 6-minute walk test and quality of life even with unsupervised, home-based pulmonary rehabilitation. In the resource-poor settings, the goal of rehabilitation may be achieved by incorporating regular unsupervised exercise in daily routine. This is not only better accepted and more suitable but is also more feasible for the lifelong maintenance of rehabilitation.     

The electrodiagnostic evaluation of radiculopathy

Electrodiagnostic studies play an important role in the evaluation of radiculopathy. This article reviews the use of standard nerve conduction studies, late responses, evoked potentials, and needle electrode examination in the work-up of lumbosacral and cervical radiculopathy.