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Abstract Background Enteric infections are hypothesized to be associated with intussusception in children. A small increase in intussusception following rotavirus vaccination has been seen in some settings. We conducted post-marketing surveillance for intussusception following rotavirus vaccine, Rotavac introduction in India and evaluated association of intussusception with enteric pathogens. Methods In a case-control study nested within a large sentinel hospital-based surveillance program in India, stool samples from 272 children aged less than 2 years admitted for intussusception and 272 age-, gender- and location-matched controls were evaluated with Taqman array card based molecular assays to detect enteric viruses, bacterial enteropathogens and parasites. Matched case-control analysis with conditional logistic regression evaluated association of enteropathogens with intussusception. Population attributable fractions (PAF) were calculated for enteropathogens significantly associated with intussusception. Results The most prevalent enteropathogens in cases and controls were enteroaggregative Escherichia coli, adenovirus 40/41, adenovirus C serotypes and enteroviruses. Children with intussusception were more likely to harbor adenovirus C serotypes (adjusted odds-ratio (aOR) = 1.74; 95% confidence interval (CI) 1.06–2.87) and enteroviruses (aOR = 1.77; 95% CI 1.05–2.97) than controls. Rotavirus was not associated with increased intussusception risk. Adenovirus C (PAF = 16.9%; 95% CI 4.7% − 27.6%) and enteroviruses (PAF = 14.7%; 95% CI 4.2% − 24.1%) had the highest population attributable fraction for intussusception. Conclusion Adenovirus C serotypes and enteroviruses were significantly associated with intussusception in Indian children. Rotavirus was not associated with risk of intussusception.

Abstract Objective Retinoschisis and Norrie disease are X-linked recessive retinal disorders caused by mutations in RS1 and NDP genes respectively. Both are likely to be monogenic and no locus heterogeneity has been reported. However, there are reports showing overlapping features of Norrie disease and retinoschisis in a NDP knock-out mouse model and also the involvement of both the genes in retinoschisis patients. Yet, the exact molecular relationships between the two disorders have still not been understood. The study investigated the association between retinoschisin (RS1) and norrin (NDP) using in vitro and in silico approaches. Specific protein–protein interaction between RS1 and NDP was analyzed in human retina by co-immunoprecipitation assay and MALDI-TOF mass spectrometry. STRING database was used to explore the functional relationship. Result Co-immunoprecipitation demonstrated lack of a direct interaction between RS1 and NDP and was further substantiated by mass spectrometry. However, STRING revealed a potential indirect functional association between the two proteins. Progressively, our analyses indicate that FZD4 protein interactome via PLIN2 as well as the MAP kinase signaling pathway to be a likely link bridging the functional relationship between retinoschisis and Norrie disease.

Abstract Background Immunomodulatory effects of Tinospora crispa have been investigated due to its traditional use to treat several inflammatory disorders associated to the immune system. The present study reports the underlying mechanisms involved in the stimulation of 80% ethanol extract of T. crispa stems on pro-inflammatory mediators release in lipopolysaccharide (LPS)-primed U937 human macrophages via MyD88-dependent pathways. Methods Release of interleukin (IL)-1β and tumor necrosis factor (TNF)-α, and production of prostaglandin E2 (PGE2) were determined by using enzyme-linked immunosorbent assay (ELISA). Immunoblot technique was executed to determine the activation of MAPKs molecules, NF-κB, PI3K-Akt and cyclooxygenase-2 (COX-2) protein. Determination of pro-inflammatory cytokines and COX-2 relative gene expression levels was by performing the real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). A reversed-phase HPLC method was developed and validated to standardize the T. crispa extract and chemical profiling of its secondary metabolites was performed by LC-MS/MS. Results Qualitative and quantitative analyses of chromatographic data indicated that syringin and magnoflorine were found as the major components of the extract. T. crispa-treatment prompted activation of NF-κB by enhancing IKKα/β and NF-κB (p65) phosphorylation, and degradation of IκBα. The extract upregulated COX-2 protein expression, release of pro-inflammatory mediators and MAPKs (ERK, p38 and JNK) phosphorylation as well as Akt dose-dependently. T. crispa extract also upregulated the upstream signaling adaptor molecules, toll-like receptor 4 (TLR4) and MyD88. T. crispa-treatment also upregulated the pro-inflammatory markers mRNA expression. Conclusion The results suggested that T. crispa extract stimulated the MyD88-dependent signaling pathways by upregulating the various immune inflammatory related parameters.

Abstract Background Agnogenic myeloid metaplasia (AMM) is one of the Philadelphia chromosome negative myeloproliferative disorder and is diagnosed by hyperplasia of atypical megakaryocytes, hepatosplenomegaly, extramedullary hematopoiesis and bone marrow fibrosis. Fibrosis is considered to be a secondary consequence of enhanced levels of fibrogenic growth factors such as TGF β1, bFGF and PDGF produced by enhanced numbers of megakaryocytes, while the primary cause is considered to be the enhanced proliferation of a defective stem cell. We have previously reported that thrombopoietin (TPO) is elevated in patients with AMM. Others have reported that Mpl protein is decreased in these patients. Since TPO is essential for the development of megakaryocytes, and Mpl protein is the receptor for TPO, we extended the study of TPO/Mpl to in vitro and in vivo cell culture systems to better understand the mechanism that leads to reduced Mpl protein in AMM patients. Results Plasma TPO levels were significantly elevated and Mpl protein levels were significantly reduced in AMM patients in concordance with previous studies. Platelet Mpl transcripts in AMM were however similar to those in controls. We also cloned Mpl cDNA from AMM patients and tested for their ability to make functional proteins in vitro and in the in vivo system of 293 T human embryonic kidney cells. Their expression including the glycosylated forms was similar to those from the controls. We also measured the level of translation initiation factor, eIF4E and found it to be increased in patients with AMM demonstrating that the reduced Mpl protein may not be due to translation defects. Conclusions Our studies using the in vitro and in vivo systems further confirm that reduced Mpl protein levels are not due to defects in its transcription/translation. Reduced Mpl protein could be due to its increased internalisation owing to enhanced plasma TPO or in vivo intrinsic defects in patients with AMM.

Abstract Background Open drains are common methods of transporting solid waste and excreta in low-income urban neighborhoods. Open drains can overflow due to blockages with solid waste and during rainfall, posing exposure risks. The goal of this study was to evaluate whether pediatric enteric infection was associated with open drains and flooding in a dense, low-income, urban neighborhood. Methods As part of the MAL-ED study in Vellore, India, a cohort of 230 children provided stool specimens at 14–17 scheduled home visits and during diarrheal episodes in the first two years of life. All specimens were analyzed for enteric pathogens. Caregivers in 100 households reported on flooding of drains and households and monthly frequency of contact with open drains and flood water. Household GPS points were collected. Monthly rainfall totals for the Vellore district were collected from the Indian Meteorological Department. Clustering of reported drain and house flooding were identified by Kulldorff’s Bernoulli Spatial Scan. Differences in enteric infection were assessed for household responses and spatial clusters, with interactions between reported flooding and rainfall to approximate monthly drain flooding retrospectively, using multivariable, mixed-effects logistic regression models. Results Coverage of household toilets was low (33%), and most toilets (82%) discharged directly into open drains, suggesting poor neighborhood fecal sludge management. Odds of enteric infection increased significantly with total monthly rainfall for children who lived in households that reported that the nearby drain flooded (4% increase per cm of rain: OR: 1.04, 95% CI: 1.00–1.08) and for children in households in a downstream spatial cluster of reported drain flooding (5% increase per cm of rain: OR: 1.05, 95% CI: 1.01–1.09). There was no association between odds of enteric infection and frequency of reported contact with drain or floodwater. Conclusions Children in areas susceptible to open drain flooding had increased odds of enteric infection as rainfall increased. Results suggested that infection increased with rainfall due to neighborhood infrastructure (including poor fecal sludge management) and not frequency of contact. Thus, these exposures may not be mitigated by changes in personal behaviors alone. These results underscore the importance of improving the neighborhood environment to improve children’s health in low-income, urban settings.

Abstract Background Phyllanthus amarus has been used widely in various traditional medicines to treat swelling, sores, jaundice, inflammatory diseases, kidney disorders, diabetes and viral hepatitis, while its pharmacological and biochemical mechanisms underlying its anti-inflammatory properties have not been well investigated. The present study was carried out to investigate the effects of 80% ethanolic extract of P. amarus on pro-inflammatory mediators release in nuclear factor-kappa B (NF-кB), mitogen activated protein kinase (MAPK) and phosphatidylinositol 3-kinase/Akt (PI3K-Akt) signaling activation in lipopolysaccharide (LPS)-induced U937 human macrophages. Methods The release of prostaglandin E2 (PGE2) and pro-inflammatory cytokines, tumor necrosis factor (TNF)-α and interleukin (IL)-1β in a culture supernatant was determined by ELISA. Determination of cyclooxygenase-2 (COX-2) protein and the activation of MAPKs molecules (JNK, ERK and p38 MAPK), NF-κB and Akt in LPS-induced U937 human macrophages were investigated by immunoblot technique. The relative gene expression levels of COX-2 and pro-inflammatory cytokines were measured by using qRT-PCR. The major metabolites of P. amarus were qualitatively and quantitatively analyzed in the extract by using validated reversed-phase high performance liquid chromatography (HPLC) methods. Results P. amarus extract significantly inhibited the production of pro-inflammatory mediators (TNF-α, IL-1β, PGE2) and COX-2 protein expression in LPS-induced U937 human macrophages. P. amarus-pretreatment also significantly downregulated the increased mRNA transcription of pro-inflammatory markers (TNF-α, IL-1β, and COX-2) in respective LPS-induced U937 macrophages. It downregulated the phosphorylation of NF-κB (p65), IκBα, and IKKα/β and restored the degradation of IκBα, and attenuated the expression of Akt, JNK, ERK, and p38 MAPKs phosphorylation in a dose-dependent manner. P. amarus extract also downregulated the expression of upstream signaling molecules, TLR4 and MyD88, which play major role in activation of NF-κB, MAPK and PI3K-Akt signaling pathways. The quantitative amounts of lignans, phyllanthin, hypophyllahtin and niranthin, and polyphenols, gallic acid, geraniin, corilagin, and ellagic acid in the extract were determined by HPLC analysis. Conclusion The study revealed that P. amarus targeted the NF-κB, MAPK and PI3K-Akt signaling pathways to exert its anti- inflammatory effects by downregulating the prospective inflammatory signaling mediators.