p-21 Activated Kinase as a Molecular Target for Chemoprevention in Diabetes

Hypothesis: Anti-diabetic drugs modulate p-21 activated kinase (PAK) signaling. Introduction: Type 2 diabetes mellitus (T2DM) is a chronic inflammatory disease associated with increased cancer risk. PAK signaling is implicated in cellular homeostasis when regulated, and cancer when unrestrained. Recent reports provided a role for PAK signaling in glucose homeostasis, but the role of PAKs in the pathogenesis of T2DM is unknown. Here, we performed a mini-meta-analysis to explore if anti-diabetic drugs modify PAK signaling pathways, and provide insight regarding modulation of these pathways, to potentially reduce diabetes-associated cancer risk. Methods: PAK interacting partners in T2DM were identified using the online STRING database. Correlation studies were performed via systematic literature review to understand the effect of anti-diabetic drugs on PAK signaling. A mini-meta-analysis correlated multiple clinical studies and revealed the overall clinical response rate and percentage of adverse events in piogliazone (n = 53) and metformin (n = 91) treated patients with PAK-associated diseases. Results: A total of 30 PAK interacting partners were identified (10: reduced beta-cell mass; 10: beta-cell dysfunction; 10: obesity-insulin resistance), which were highly associated with Wnt, and G-protein signaling. The anti-diabetic drug metformin activated signaling pathways upstream; whereas pioglitazone inhibited pathways downstream of PAK. Overall, clinical response upon pioglitazone treatment was 53%. Seventy-nine percent of pioglitazone and 75% of metformin treated patients had adverse events. Pioglitazone reduced molecular-PAK biomarkers of proliferation (Ki67 and CyclinD1), and metformin had the opposite effect. Conclusions: PAK signaling in T2DM likely involves Wnt and G-protein signaling, which may be altered by the anti-diabetic drugs metformin and pioglitazone. Apart from the therapeutic limitations of adverse events, pioglitazone may be promising in chemoprevention. However long-term multi-centered studies, which initiate pioglitazone treatment early will be required to fully assess the full potential of these drugs

PAK1 modulates a PPARγ/NF-κB cascade in intestinal inflammation

P21-activated kinases (PAKs) are multifunctional effectors of Rho GTPases with both kinase and scaffolding activity. Here, we investigated the effects of inflammation on PAK1 signaling and its role in colitis-driven carcinogenesis. PAK1 and p-PAK1 (Thr423) were assessed by immunohistochemistry, immunofluorescence, and Western blot. C57BL6/J wildtype mice were treated with a single intraperitoneal TNFα injection. Small intestinal organoids from these mice and from PAK1-KO mice were cultured with TNFα. NF-κB and PPARγ were analyzed upon PAK1 overexpression and silencing for transcriptional/translational regulation. PAK1 expression and activation was increased on the luminal intestinal epithelial surface in inflammatory bowel disease and colitis-associated cancer. PAK1 was phosphorylated upon treatment with IFNγ, IL-1β, and TNFα. In vivo, mice administered with TNFα showed increased p-PAK1 in intestinal villi, which was associated with nuclear p65 and NF-κB activation. p65 nuclear translocation downstream of TNFα was strongly inhibited in PAK1-KO small intestinal organoids. PAK1 overexpression induced a PAK1–p65 interaction as visualized by co-immunoprecipitation, nuclear translocation, and increased NF-κB transactivation, all of which were impeded by kinase-dead PAK1. Moreover, PAK1 overexpression downregulated PPARγ and mesalamine recovered PPARγ through PAK1 inhibition. On the other hand PAK1 silencing inhibited NF-κB, which was recovered using BADGE, a PPARγ antagonist. Altogether these data demonstrate that PAK1 overexpression and activation in inflammation and colitis-associated cancer promote NF-κB activity via suppression of PPARγ in intestinal epithelial cells

Comparative analysis of enzyme-linked immunosorbent assay and direct microscopy for the diagnosis of Giardia intestinalis in fecal samples

Context: Giardiasis is one of the most common nonviral infections causing diarrheal illness worldwide. In this prospective cross-sectional study, we evaluated the RIDASCREEN ® Giardia kit for detection of Giardia intestinalis in stool samples and compared the results with direct microscopy. Materials and methods: A total of 360 fecal samples were collected. They were then processed by wet film, iodine preparation and an enzyme-linked immunosorbent assay (ELISA) kit to determine the presence of Giardia trophozoites and cysts. Statistical analysis was performed by sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy. Results and Conclusion: Of the 360 cases, 17.2% samples were positive for Giardia by direct microscopy and 23.6% were found to be positive by ELISA (sensitivity ~97%), but specificity was ~92% only. Because of less specificity, we need to perform ELISA in congruence with direct microscopy, etc. Further studies need to be performed on a larger sample size using other molecular tests in order to get more accurate estimations

Evaluation of enzyme immunoassay based on detection of pLDH antigen for the diagnosis of malaria

Introduction: Timely diagnosis of malaria is a challenge in most endemic areas due to lack of resources. The methods most commonly used are microscopy, regarded as the gold standard, and rapid dipstick tests (RDT) which detect antigens in blood. Enzyme-Linked Immuno Sorbent Assay (ELISA) based tests are fast and easy to perform especially when large number of samples have to be tested. p-LDH is a highly sensitive marker of malaria in blood The present study was done to assess the diagnostic performance of a p-LDH based ELISA on samples from clinically suspected malaria patients. Methods: We tested the sensitivity and specificity of a pLDH based, commercially available ELISA kit on both microscopy positive and negative samples. Microscopy was done for all suspected malaria patients and of these 146 samples (73 positive and 73 negative) were tested by the ErbaLisa PAN (LDH) malaria ELISA kit as well SD Bioline malaria antigen test (RDT) based on detection of both HRP-2 and p-LDH common to all four species. Results: The sensitivity of Elisa was 95.9% while specificity was 93.2 % compared to gold standard microscopy while RDTs had 91.8 % sensitivity and 86.3 % specificity. All 67 samples positive by both microscopy and RDT were also positive by ELISA. Conclusion: p-LDH based ELISA promises to be a cost effective and reliable option for diagnosis of malaria in endemic areas like India

Incidence and risk factors associated with Acinetobacter species infection in hospitalised patients in a tertiary care hospital in North- India

Purpose: Acinetobacter species has become a worldwide concern as a cause of serious nosocomial infections. This study is done to determine the incidence, resistance pattern and risk factors associated with Acinetobacter species infection in hospitalized patients of Era’s Lucknow Medical College and Hospital (ELMCH), Lucknow. Methods: Total 1850 samples were taken from patients admitted in wards of different departments of ELMCH from Sep 2012 to Sep 2013. Identification of isolates was done by colony characteristics and biochemical reactions. Antimicrobial susceptibility of Acinetobacter isolates was done using Kirby Bauer disc diffusion method according to Clinical Laboratory Standards Institute (CLSI) guidelines. Risk factors associated with Acinetobacter infection were found out. Results and Discussion: 46 isolates were identified as Acinetobacter species. High level of resistance was observed for most of the antibiotics tested. More than 80% of isolates were resistant to amikacin, gentamycin, ceftriaxone, ciprofloxacin and tetracycline. 30.43% of isolates were resistant to cefoperazone/ sulbactum and resistance to imipenem and colistin was 23.91% and 19.56% respectively. There was no independent risk factor for Acinetobacter infection identified but its infection was significantly associated with longer hospital stay (>48 hours), antibiotic intake in last 72 hours and use of invasive devices specially peripheral venous catheter