Road to Alzheimer's disease: the pathomechanism underlying

Alzheimer's disease (AD), the most common cause of dementia, results from the interplay of various deregulated mechanisms triggering a complex pathophysiology. The neurons suffer from and slowly succumb to multiple irreversible damages, resulting in cell death and thus memory deficits that characterize AD. In spite of our vast knowledge, it is still unclear as to when the disease process starts and how long the perturbations continue before the disease manifests. Recent studies provide sufficient evidence to prove amyloid β (Aβ) as the primary cause initiating secondary events, but Aβ is also known to be produced under normal conditions and to possess physiological roles, hence, the questions that remain are: What are the factors that lead to abnormal Aβ production? When does Aβ turn into a pathological molecule? What is the chain of events that follows Aβ? The answers are still under debate, and further insight may help us in creating better diagnostic and therapeutic options in AD. The present article attempts to review the current literature regarding AD pathophysiology and proposes a pathophysiologic cascade in AD.     

Attitudes and practices of medical graduates in Delhi towards gifts from the pharmaceutical industry

Pharmaceutical companies use a variety of strategies, including gifts, to influence physicians. In December 2009, the Medical Council of India amended the Code of Medical Ethics to ban medical professionals from accepting gifts from pharmaceutical companies. In view of this ban, it is important to find out the magnitude and contours of the problem amongst Indian medical professionals. We aimed to study, through an e-mail based survey, the attitudes and practices of young resident doctors and interns from two medical colleges of New Delhi regarding acceptance of gifts from the pharmaceutical industry. We e-mailed the questionnaire to 150 fresh graduates. We found that the majority of graduates agreed with existing guidelines: they accepted low cost gifts but considered expensive gifts unrelated to patient welfare unethical. Despite the low response rate, this study is important because data from India on attitudes and practices of medical professionals regarding gifts from the pharmaceutical industry are virtually non-existent.     

Intracystic papillary carcinoma of the breast: report of two cases

Intracystic papillary carcinoma (IPC) of the breast has traditionally been considered to be a variant of ductal carcinoma in-situ (DCIS). It is an uncommon tumor accounting for less than 3% of all breast cancers and predominantly affects elderly women. IPC is extremely rare in men and only few cases have been reported in the literature. The tumor has excellent prognosis regardless of whether it is in-situ or invasive. Hence an accurate diagnosis plays a crucial role in the management of patients with IPC. We report two cases of IPC, one in a 68-year-old woman and the other one in a 70-year-old man. The diagnosis was suspected on fine needle aspiration cytology (FNAC) and was confirmed by histopathology.     

Expression and function of a family of transmembrane kinases from the protozoan parasite Entamoeba histolytica

The signaling proteome of Entamoeba histolytica is made of transmembrane kinases (TMKs) that are rarely found in unicellular eukaryotes. There are 90 TMK genes reported for E. histolytica, and these have been grouped into nine distinct families based on motifs present on both extracellular and kinase domains. Of these, the B1 family was chosen for further analysis. Genomic sequencing revealed the presence of 28 members belonging to this family. Genes corresponding to the majority of these were truncated and not considered for further analysis. Only five members were full length and contained both extracellular and cytosolic kinase domains. BLAST analysis revealed the presence of homologs of these B1 TMKs in the nonpathogenic Entamoeba dispar. However, the ligand binding domains of the orthologous B1 TMKs of the two species showed considerable divergence, indicating the possibility of a correlation with the pathogenic potential of the organism. Only two of the five full-length copies (B1.I.1 and B1.I.2) were expressed in E. histolytica under the culture conditions used. Antisera generated against the extracellular domain of B1.I.1 stained the cell surface, particularly the areas of contact between the trophozoites. Staining was also seen in the frontal and posterior regions of the motile amoeba. An amoebic cell line expressing a truncated version of the B1.I.1 that lacked the kinase domain was generated. Inducible expression of the truncated TMK resulted in a decrease in cellular proliferation and an increase in sensitivity to serum starvation. Our data indicate that the B1.I class of TMKs is involved in parasite proliferation.