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1.  Role of CYP2E1 gene polymorphisms association with hepatitis risk in Northeast India 
AIM: To investigate hepatitis virus, genetic and environmental factors, and their interactions in predisposing patients to liver diseases in Northeast India.
METHODS: A total of 104 jaundice patients and 124 community controls were included. Serological analysis was performed by routine enzyme-linked immunosorbent assay, and nucleic acid testing for hepatitis viruses was done by polymerase chain reaction (PCR), followed by PCR direct sequencing for viral genotyping. Cytochrome P450 2E1 (CYP2E1) polymorphism was studied by PCR-restriction fragment length polymorphism. Nitrite and volatile nitrosamines in indigenous foods consumed routinely by the Northeast Indian ethnic population were estimated by Griess’s reagent and GC-MS, respectively.
RESULTS: Hepatitis A virus (HAV) infection was predominantly prevalent (36.5%) in our cohort, followed by hepatitis B virus (HBV), hepatitis E virus (HEV) and hepatitis C virus. HBV genotype D and HEV genotype 1 were the most dominant. CYP2E1 c1/c2 genotype frequency was comparatively higher in alcoholic (P < 0.0001, OR = 30.5) and cryptogenic (P = 0.014, OR = 8.714) patients, and was associated with significantly higher hepatitis risk (P = 0.0.007, OR = 6.489). Mutant C allele of Cyp2E1 DraI frequency was comparatively higher in HAV (P = 0.006), alcoholic (P = 0.003) and cryptogenic (P = 0.014) cases, and was associated with overall hepatitis risk (P = 0.026, OR = 5.083). Indigenous foods, Gundruk, Kharoli, betel leaf and nuts were found to have the highest nitrite content.
CONCLUSION: Apart from viral factors, CYP2E1 polymorphism might be associated with increased risk of liver diseases in Northeast India. Indigenous foods that contain nitrite and nitrosamine might be an associated risk factor.
PMCID: PMC2955249  PMID: 20939108
Viral hepatitis; Cytochrome P450 2E1; Gene polymorphism; Nitrites; Nitrosamines
2.  Mitogen-Activated Protein Kinase-Dependent Interleukin-1α Intracrine Signaling Is Modulated by YopP during Yersinia enterocolitica Infection 
Infection and Immunity  2012;80(1):289-297.
Yersinia enterocolitica is a food-borne pathogen that preferentially infects the Peyer's patches and mesenteric lymph nodes, causing an acute inflammatory reaction. Even though Y. enterocolitica induces a robust inflammatory response during infection, the bacterium has evolved a number of virulence factors to limit the extent of this response. We previously demonstrated that interleukin-1α (IL-1α) was critical for the induction of gut inflammation characteristic of Y. enterocolitica infection. More recently, the known actions of IL-1α are becoming more complex because IL-1α can function both as a proinflammatory cytokine and as a nuclear factor. In this study, we tested the ability of Y. enterocolitica to modulate intracellular IL-1α-dependent IL-8 production in epithelial cells. Nuclear translocation of pre-IL-1α protein and IL-1α-dependent secretion of IL-8 into the culture supernatant were increased during infection with a strain lacking the 70-kDa virulence plasmid compared to the case during infection with the wild type, suggesting that Yersinia outer proteins (Yops) might be involved in modulating intracellular IL-1α signaling. Infection of HeLa cells with a strain lacking the yopP gene resulted in increased nuclear translocation of pre-IL-1α and IL-1α-dependent secretion of IL-8 similar to what is observed with bacteria lacking the virulence plasmid. YopP is a protein acetylase that inhibits mitogen-activated protein kinase (MAP kinase)- and NF-κB-dependent signal transduction pathways. Nuclear translocation of pre-IL-1α and IL-1α-dependent secretion of IL-8 in response to Yersinia enterocolitica infection were dependent on extracellular signal-regulated kinase (ERK) and p38 MAP kinase signaling but independent of NF-κB. These data suggest that Y. enterocolitica inhibits intracellular pre-IL-1α signaling and subsequent proinflammatory responses through inhibition of MAP kinase pathways.
PMCID: PMC3255648  PMID: 22083707
3.  Antimicrobial Activity of Acanthus ilicifolius (L.) 
The antimicrobial activity of alcoholic, butanolic and chloroform extracts of leaves and roots of the plant Acanthus ilicifolius ware studied. Ampicillin and clotrimazole were used as standard antibacterial and antifungal agents respectively. The result of the study revealed that the alcoholic extract and chloroform extract of leaves exhibited strong inhibitory action against Bacillus subtilis, Staphylococcus aureus, Candida albicans, Aspergillus fumigatus and Aspergillus niger and moderate inhibitory action against Pseudomonas aeruginosa and Proteus vulgaris. The rest of the extracts showed moderate activity.
PMCID: PMC3040886  PMID: 21369453
Acanthus ilicifolius; agar cup-plate method; antimicrobial activity; mangrove
4.  Steroidogenic Activity of StAR Requires Contact with Mitochondrial VDAC1 and Phosphate Carrier Protein* 
The Journal of Biological Chemistry  2008;283(14):8837-8845.
The steroidogenic acute regulatory protein (StAR) is required for adrenal and gonadal steroidogenesis and for male sexual differentiation. StAR acts on the outer mitochondrial membrane (OMM) to facilitate movement of cholesterol from the OMM to the inner mitochondrial membrane to be converted to pregnenolone, the precursor of all steroid hormones. The mechanisms of the action of StAR remain unclear; the peripheral benzodiazepine receptor, an OMM protein, appears to be involved, but the identity of OMM proteins that interact with StAR remain unknown. Here we demonstrate that phosphorylated StAR interacts with voltage-dependent anion channel 1 (VDAC1) on the OMM, which then facilitates processing of the 37-kDa phospho-StAR to the 32-kDa intermediate. In the absence of VDAC1, phospho-StAR is degraded by cysteine proteases prior to mitochondrial import. Phosphorylation of StAR by protein kinase A requires phosphate carrier protein on the OMM, which appears to interact with StAR before it interacts with VDAC1. VDAC1 and phosphate carrier protein are the first OMM proteins shown to contact StAR.
PMCID: PMC2276375  PMID: 18250166
6.  Stillbirth and early neonatal mortality in rural Central Africa 
To develop a prospective perinatal registry that characterizes all deliveries, differentiates between stillbirths and early neonatal deaths (ENDs), and determines the ratio of fresh to macerated stillbirths in the northwest Democratic Republic of Congo.
Birth outcomes were obtained from 4 rural health districts.
A total of 8230 women consented, END rate was 32 deaths per 1000 live births, and stillbirth rate was 33 deaths per 1000 deliveries. The majority (75%) of ENDs and stillbirths occurred in neonates weighing 1500 g or more. Odds of stillbirth and END increased in mothers who were single or who did not receive prenatal care, and among premature, low birth weight, or male infants. The ratio of fresh to macerated stillbirths was 4:1.
Neonates weighing 1500 g or more at birth represent a group with a high likelihood of survival in remote areas, making them potentially amenable to targeted intervention packages. The ratio of fresh to macerated stillbirths was approximately 10-fold higher than expected, suggesting a more prominent role for improved intrapartum obstetric interventions.
PMCID: PMC3972762  PMID: 19201402
Africa; Early neonatal death; Fresh and macerated stillbirth; Low-income country
7.  Primary Midgut Carcinoid, a Rare Cause of Paraneoplastic Limbic Encephalitis: A Case Report 
A 60-year-old male presented with an unexplained seizure whose aetiology could not be demonstrated. After 8 weeks, patient on evaluation for abdominal pain was detected to have primary midgut carcinoid with nodal and hepatic metastasis. Patient underwent cytoreductive surgery and metastatectomy with successful outcome. The case is being presented for its rarity and the need to recognize the paraneoplastic neurological manifestations of these rare neuroendocrine tumors.
PMCID: PMC3972543
Neuroendocrine tumor; Paraneoplastic limbic encephalitis
8.  Do Practicing Clinicians Agree with Expert Ratings of Neonatal Intensive Care Unit Quality Measures? 
To assess the level of agreement when selecting quality measures for inclusion in a composite index of neonatal intensive care quality (Baby-MONITOR) between two panels: one comprised of academic researchers (Delphi) and another comprised of academic and clinical neonatologists (Clinician).
In a modified Delphi process, a panel rated twenty eight quality measures. We assessed clinician agreement with the Delphi panel by surveying a sample of forty eight neonatal intensive care practitioners. We asked the clinician group to indicate their level of agreement with the Delphi panel for each measure using a five- point scale (much too high, slightly too high, reasonable, slightly too low, and much too low). In addition, we asked clinicians to select measures for inclusion in the Baby-MONITOR based on a yes or no vote and a pre-specified two-thirds majority for inclusion.
Twenty three (47.9%) of the clinicians responded to the survey. We found high levels of agreement between the Delphi and clinician panels, particularly across measures selected for the Baby-MONITOR. Clinicians selected the same nine measures for inclusion in the composite as the Delphi panel. For these nine measures, 74% of clinicians indicated that the Delphi panel rating was ‘reasonable’.
Practicing clinicians agree with an expert panel on the measures that should be included in the Baby-MONITOR, enhancing face validity.
PMCID: PMC3963391  PMID: 22241483
infant; newborn; quality of health care; measurement; composite indicator
9.  Using Verbal Autopsy to ascertain perinatal cause of death: Are trained non-physicians adequate? 
To develop a standardized verbal autopsy (VA) training program and evaluate whether its implementation resulted in comparable knowledge required to classify perinatal cause of death (COD) by physicians and non-physicians.
Training materials, case studies, and written and mock scenarios for this VA program were developed using conventional VA and ICD-10 guidelines. This program was used to instruct physicians and non-physicians in VA methodology using a train-the-trainer model. Written tests of cognitive and applied knowledge required to classify perinatal COD were administered before and after training to evaluate the effect of the VA training program.
53 physicians and non-physicians (nurse-midwives/nurses and Community Health Workers [CHW]) from Pakistan, Zambia, the Democratic Republic of Congo, and Guatemala were trained. Cognitive and applied knowledge mean scores among all trainees improved significantly (12.8 and 28.8% respectively, p<0.001). Cognitive and applied knowledge post-training test scores of nurse-midwives/nurses were comparable to those of physicians. CHW (high-school graduates with 15 months or less formal health/nursing training) had the largest improvements in post-training applied knowledge with scores comparable to those of physicians and nurse-midwives/nurses. However, CHW cognitive knowledge post-training scores were significantly lower than those of physicians and nurses.
With appropriate training in VA, cognitive and applied knowledge required to determine perinatal COD is similar for physicians and nurses-midwives/nurses. This suggests that midwives and nurses may play a useful role in determining COD at the community level, which may be a practical way to improve the accuracy of COD data in rural, remote, geographic areas.
PMCID: PMC3959775  PMID: 19799757
perinatal mortality; education; non-physicians; verbal autopsy
10.  Overexpressed PKCδ Downregulates the Expression of PKCα in B16F10 Melanoma: Induction of Apoptosis by PKCδ via Ceramide Generation 
PLoS ONE  2014;9(3):e91656.
In the present study, we observed a marked variation in the expression of PKCα and PKCδ isotypes in B16F10 melanoma tumor cells compared to the normal melanocytes. Interestingly, the tumor instructed expression or genetically manipulated overexpression of PKCα isotype resulted in enhanced G1 to S transition. This in turn promoted cellular proliferation by activating PLD1 expression and subsequent AKT phosphorylation, which eventually resulted in suppressed ceramide generation and apoptosis. On the other hand, B16F10 melanoma tumors preferentially blocked the expression of PKCδ isotype, which otherwise could exhibit antagonistic effects on PKCα-PLD1-AKT signaling and rendered B16F10 cells more sensitive to apoptosis via generating ceramide and subsequently triggering caspase pathway. Hence our data suggested a reciprocal PKC signaling operational in B16F10 melanoma cells, which regulates ceramide generation and provide important clues to target melanoma cancer by manipulating the PKCδ-ceramide axis.
PMCID: PMC3954766  PMID: 24632809
11.  Discovering the Recondite Secondary Metabolome Spectrum of Salinispora Species: A Study of Inter-Species Diversity 
PLoS ONE  2014;9(3):e91488.
Patterns of inter-species secondary metabolite production by bacteria can provide valuable information relating to species ecology and evolution. The complex nature of this chemical diversity has previously been probed via directed analyses of a small number of compounds, identified through targeted assays rather than more comprehensive biochemical profiling approaches such as metabolomics. Insights into ecological and evolutionary relationships within bacterial genera can be derived through comparative analysis of broader secondary metabolite patterns, and this can also eventually assist biodiscovery search strategies for new natural products. Here, we investigated the species-level chemical diversity of the two marine actinobacterial species Salinispora arenicola and Salinispora pacifica, isolated from sponges distributed across the Great Barrier Reef (GBR), via their secondary metabolite profiles using LC-MS-based metabolomics. The chemical profiles of these two species were obtained by UHPLC-QToF-MS based metabolic profiling. The resultant data were interrogated using multivariate data analysis methods to compare their (bio)chemical profiles. We found a high level of inter-species diversity in strains from these two bacterial species. We also found rifamycins and saliniketals were produced exclusively by S. arenicola species, as the main secondary metabolites differentiating the two species. Furthermore, the discovery of 57 candidate compounds greatly increases the small number of secondary metabolites previously known to be produced by these species. In addition, we report the production of rifamycin O and W, a key group of ansamycin compounds, in S. arenicola for the first time. Species of the marine actinobacteria harbour a much wider spectrum of secondary metabolites than suspected, and this knowledge may prove a rich field for biodiscovery as well as a database for understanding relationships between speciation, evolution and chemical ecology.
PMCID: PMC3951395  PMID: 24621594
12.  Comparison of Three Quality of Life Instruments in Lymphatic Filariasis: DLQI, WHODAS 2.0, and LFSQQ 
The Global Program to Eliminate Lymphatic Filariasis aims to interrupt transmission of lymphatic filariasis and manage morbidity in people currently living with the disease. A component of morbidity management is improving health-related quality of life (HRQoL) in patients. Measurement of HRQoL in current management programs is varied because of the lack of a standard HRQoL tool for use in the lymphatic filariasis population.
Methodology/Principal Findings
In this study, the psychometric properties of three health status measures were compared when used in a group of lymphatic filariasis patients and healthy controls. The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0), the Dermatology Life Quality Index (DLQI), and the Lymphatic Filariasis Quality of Life Questionnaire (LFSQQ) were administered to 36 stage II and stage III lymphatic filariasis subjects and 36 age and sex matched controls in Kerala, India. All three tools yielded missing value rates lower than 10%, suggesting high feasibility. Highest internal consistency was seen in the LFSQQ (α = 0.97). Discriminant validity analysis demonstrated that HRQoL was significantly lower in the LF group than in controls for the WHODAS 2.0, DLQI, and LFSQQ, but total HRQoL scores did not differ between stage II and stage III lymphedema subjects. The LFSQQ total score correlated most strongly with the WHODAS 2.0 (r = 0.91, p<0.001) and DLQI (r = 0.81, p<0.001).
The WHODAS 2.0, DLQI, and LFSQQ demonstrate acceptable feasibility, internal consistency, discriminate validity, and construct validity. Based on our psychometric analyses, the LFSQQ performs the best and is recommended for use in the lymphatic filariasis population.
Author Summary
Lymphatic filariasis affects approximately 120 million people and is the second leading cause of life-long disability worldwide. Because lymphatic filariasis is one of the World Health Organization's six eradicable diseases, much effort has been placed into reducing transmission of the disease and managing morbidity. Novel interventions frequently use health-related quality of life as an outcome measure to monitor efficacy of the intervention. In an effort to delineate the strengths and weaknesses of health status measures and recommend use of a single tool in the lymphatic filariasis population, we compared the use of three health status tools (The World Health Organization Disability Assessment Schedule 2.0, the Dermatology Life Quality Index, and the Lymphatic Filariasis Quality of Life Questionnaire) in lymphatic filariasis subjects and healthy controls in Kerala, India. The Lymphatic Filariasis Quality of Life Questionnaire performed the best by discriminating well between subjects and controls, possessing significant content overlap with the other two tools, yielding a low missing value rate, and being internally consistent. This is the first study to compare health status measures in lymphatic filariasis subjects and provides insight into the use of the tools in quality of life analysis.
PMCID: PMC3930502  PMID: 24587467
13.  An alternative strategy for perinatal verbal autopsy coding: single versus multiple coders 
To determine the comparability between cause of death by a single physician coder and a two-physician panel, using verbal autopsy.
The study was conducted between May 2007 and June 2008. Within a week of a perinatal death in 38 rural remote communities in Guatemala, the Democratic Republic of Congo, Zambia and Pakistan, VA questionnaires were completed. Two independent physicians, unaware of the others decisions, assigned an underlying cause of death, in accordance with the causes listed in the chapter headings of the International classification diseases and related health problems, 10th revision (ICD-10). Cohen's kappa statistic was used to assess level of agreement between physician coders.
There were 9461 births during the study period; 252 deaths met study enrollment criteria and underwent verbal autopsy. Physicians assigned the same COD for 75% of stillbirths (K=0.69; 95% confidence interval: 0.61–0.78) and 82% early neonatal deaths (K=0.75; 95% confidence interval: 0.65–0.84). The patterns and proportion of stillbirths and early neonatal deaths determined by the physician coders were very similar compared to causes individually assigned by each physician. Similarly, rank order of the top 5 causes of stillbirth and early neonatal death were identical for each physician.
This study raises important questions about the utility of a system of multiple coders that is currently widely accepted, and speculates that a single physician coder may be an effective and economical alternative to VA programs that use traditional two-physician panels to assign COD.
PMCID: PMC3927400  PMID: 21371206
verbal autopsy; perinatal death; comparing coders
14.  2D NMR-based metabolomics uncovers interactions between conserved biochemical pathways in the model organism Caenorhabditis elegans 
ACS chemical biology  2012;8(2):314-319.
Ascarosides are small-molecule signals that play a central role in C. elegans biology, including dauer formation, aging, and social behaviors, but many aspects of their biosynthesis remain unknown. Using automated 2D NMR-based comparative metabolomics, we identified ascaroside ethanolamides as shunt metabolites in C. elegans mutants of daf-22, a gene with homology to mammalian 3-ketoacyl-CoA thiolases predicted to function in conserved peroxisomal lipid β-oxidation. Two groups of ethanolamides feature β-keto functionalization confirming the predicted role of daf-22 in ascaroside biosynthesis, whereas α-methyl substitution points to unexpected inclusion of methylmalonte at a late stage in the biosynthesis of long-chain fatty acids in C. elegans. We show that ascaroside ethanolamide formation in response to defects in daf-22 and other peroxisomal genes is associated with severe depletion of endocannabinoid pools. These results indicate unexpected interaction between peroxisomal lipid β-oxidation and the biosynthesis of endocannabinoids, which are major regulators of lifespan in C. elegans. Our study demonstrates the utility of unbiased comparative metabolomics for investigating biochemical networks in metazoans.
PMCID: PMC3574178  PMID: 23163760
15.  Hepatitis C virus infection and insulin resistance 
World Journal of Diabetes  2014;5(1):52-58.
Approximately 170 million people worldwide are chronically infected with hepatitis C virus (HCV). Chronic HCV infection is the leading cause for the development of liver fibrosis, cirrhosis, hepatocellular carcinoma (HCC) and is the primary cause for liver transplantation in the western world. Insulin resistance is one of the pathological features in patients with HCV infection and often leads to development of type II diabetes. Insulin resistance plays an important role in the development of various complications associated with HCV infection. Recent evidence indicates that HCV associated insulin resistance may result in hepatic fibrosis, steatosis, HCC and resistance to anti-viral treatment. Thus, HCV associated insulin resistance is a therapeutic target at any stage of HCV infection. HCV modulates normal cellular gene expression and interferes with the insulin signaling pathway. Various mechanisms have been proposed in regard to HCV mediated insulin resistance, involving up regulation of inflammatory cytokines, like tumor necrosis factor-α, phosphorylation of insulin-receptor substrate-1, Akt, up-regulation of gluconeogenic genes like glucose 6 phosphatase, phosphoenolpyruvate carboxykinase 2, and accumulation of lipid droplets. In this review, we summarize the available information on how HCV infection interferes with insulin signaling pathways resulting in insulin resistance.
PMCID: PMC3932427  PMID: 24567801
Hepatitis C virus; Insulin resistance; Insulin receptor substrate 1; Protein kinase B; mammalian target of rapamycin/S6K1; Suppressor of cytokine signaling 3; Glucose transporter-4; Lipid metabolism; Anti-viral therapy
16.  Multiple Tumor Suppressor microRNAs Regulate Telomerase and TCF7, an Important Transcriptional Regulator of the Wnt Pathway 
PLoS ONE  2014;9(2):e86990.
The human TERT (hTERT) gene encodes the telomerase catalytic subunit which plays a role in telomerase regulation. Telomerase is activated in more than 90% of all human malignancies and understanding how telomerase is regulated is necessary for implementation of successful anti-cancer therapies. microRNAs (miRNAs) are important regulators of gene expression in eukaryotic cells but evidence of their role in telomerase regulation has not been documented. To determine whether hTERT activity is regulated by multiple miRNAs, eight miRNAs which have putative binding sites in the hTERT 3′UTR together with miR-138-5p were evaluated in luciferase assays with a reporter containing the hTERT 3′UTR. Six miRNAs (let-7g*, miR-133a, miR-138-5p, miR-342-5p, miR-491-5p, and miR-541-3p) specifically inhibited the expression of the reporter luciferase-driven constructs and let-7g*, miR-133a, miR-138-5p, and miR-491-5p also downregulated endogenous telomerase activity in cells. Moreover, all six miRNAs significantly inhibited cell proliferation. miRNAs (miR-133a, miR-138-5p, 342-5p, 491-5p, 541-3p) also have predicted binding sites within the 3′UTR of three genes involved in Wnt signaling (TCF7, MSI1, and PAX5). These miRNAs inhibited the expression of the luciferase reporter constructs containing 3′UTRs of these genes and downregulated protein expression of the TCF7 transcription factor, which mediates the canonical Wnt pathway. Together, these results suggest the existence of a miRNA regulatory network involving the hTERT and Wnt pathway.
PMCID: PMC3925088  PMID: 24551047
Six million stillbirths (SB) and early neonatal deaths (END) occur annually worldwide, mostly in rural settings distant from health facilities. We used verbal autopsy (VA), to understand causes of non-hospital, community-based SB and END from four low-income countries.
Study Design
This prospective observational study utilized the train-the-trainer method. VA interviewers conducted standardized interviews; in each country data were reviewed by two local physicians who assigned an underlying causes of deaths (COD).
There were 252 perinatal deaths (118 END; 134 SB) studied from pooled data. Almost half (45%) the END occurred on postnatal day 1, 19%on the second day and 16% the third day. Major early neonatal COD were infections (49%), birth asphyxia (26%), prematurity (17%) and congenital malformations (3%). Major causes of SB were infection (37%), prolonged labor (11%), antepartum hemorrhage (10%), preterm delivery (7%), cord complications (6%) and accidents (5%).
Many of these SB and END were from easily preventable causes. Over 80% of END occurred during the first 3 days of postnatal life, and >90% were due to infection, birth asphyxia and prematurity. The causes of SB were more varied, and maternal infections were the most common cause. Increased attention should be targeting at interventions that reduce maternal and neonatal infections and prevent END, particularly during the first 3 days of life.
PMCID: PMC3922534  PMID: 22076413
18.  Patient-reported outcomes following treatment of tibial non-union with circular frames 
The management of tibial non-union is challenging with protracted, often arduous, treatments. The purpose of this study was to assess patient-reported outcomes following treatment of tibial non-union in circular external fixators. Twenty-one patients with tibial non-unions who successfully completed treatment at a mean of 10.1 months (range 6–20) in a circular external fixator were sent questionnaires utilising the Enneking scoring system and Euroqol EQ-5D. There were 14 responses. The mean Enneking score was 58.0 % (34.3–77.1). Two patients were enthusiastic about their treatment, while three accepted but would not repeat the treatment. The Euroqol questionnaire found that 8 patients had difficulty with mobility, 10 had difficulty with usual activities and 12 had moderate pain. There was no statistically significant difference in the EQ VAS score of overall health state for treated patients compared with predicted scores for an age- and sex-matched UK population (77.7 vs 83.1, p = 0.07).
Electronic supplementary material
The online version of this article (doi:10.1007/s11751-014-0187-x) contains supplementary material, which is available to authorized users.
PMCID: PMC3951624  PMID: 24519370
Tibial non-union; External fixation; Ilizarov; Patient-reported outcome
19.  High Mortality Rates for Very Low Birth Weight Infants in Developing Countries Despite Training 
Pediatrics  2010;126(5):e1072-e1080.
The goal was to determine the effect of training in newborn care and resuscitation on 7-day (early) neonatal mortality rates for very low birth weight (VLBW) infants. The study was designed to test the hypothesis that these training programs would reduce neonatal mortality rates for VLBW infants.
Local instructors trained birth attendants from 96 rural communities in 6 developing countries in protocol and data collection, the World Health Organization Essential Newborn Care (ENC) course, and a modified version of the American Academy of Pediatrics Neonatal Resuscitation Program (NRP), by using a train-the-trainer model. To test the impact of ENC training, data on infants of 500 to 1499 g were collected by using a before/after, active baseline, controlled study design. A cluster-randomized, controlled trial design was used to test the impact of the NRP.
A total of 1096 VLBW (500–1499 g) infants were enrolled, and 98.5% of live-born infants were monitored to 7 days. All-cause, 7-day neonatal mortality, stillbirth, and perinatal mortality rates were not affected by ENC or NRP training.
Neither ENC nor NRP training of birth attendants decreased 7-day neonatal, stillbirth, or perinatal mortality rates for VLBW infants born at home or at first-level facilities. Encouragement of delivery in a facility where a higher level of care is available may be preferable when delivery of a VLBW infant is expected.
PMCID: PMC3918943  PMID: 20937655
neonatal mortality; perinatal mortality; stillbirth; developing countries; health care systems; very low birth weight; prematurity
20.  Meat consumption is associated with less stunting among toddlers in four diverse low-income settings 
Food and nutrition bulletin  2011;32(3):185-191.
Early growth faltering is common but is difficult to reverse after the first 2 years of life.
To describe feeding practices and growth in infants and young children in diverse low-income settings prior to undertaking a complementary feeding trial.
This cross-sectional study was conducted through the Global Network for Women’s and Children’s Health Research in Guatemala, Democratic Republic of Congo, Zambia, and Pakistan. Feeding questionnaires were administered to convenience samples of mothers of 5- to 9-month old infants and 12- to 24-month-old toddlers. After standardized training, anthropometric measurements were obtained from the toddlers. Following the 2006 World Health Organization Growth Standards, stunting was defined as length-for-age < −2SD, and wasting as weight-for-length < −2SD. Logistic regression was applied to evaluate relationships between stunting and wasting and consumption of meat (including chicken and liver and not including fish).
Data were obtained from 1,500 infants with a mean (± SD) age of 6.9 ± 1.4 months and 1,658 toddlers with a mean age of 17.2 ± 3.5 months. The majority of the subjects in both age groups were breastfed. Less than 25% of the infants received meat regularly, whereas 62% of toddlers consumed these foods regularly, although the rates varied widely among sites. Stunting rate ranged from 44% to 66% among sites; wasting prevalence was less than 10% at all sites. After controlling for covariates, consumption of meat was associated with a reduced likelihood of stunting (OR = 0.64; 95% CI, 0.46 to 0.90).
The strikingly high stunting rates in these toddlers and the protective effect of meat consumption against stunting emphasize the need for interventions to improve complementary feeding practices, beginning in infancy.
PMCID: PMC3918945  PMID: 22073791
Complementary feeding; infant growth; infant nutrition; stunting
21.  Hindlimb Muscle Morphology and Function in a New Atrophy Model Combining Spinal Cord Injury and Cast Immobilization 
Journal of Neurotrauma  2013;30(3):227-235.
Contusion spinal cord injury (SCI) animal models are used to study loss of muscle function and mass. However, parallels to the human condition typically have been confounded by spontaneous recovery observed within the first few post-injury weeks, partly because of free cage activity. We implemented a new rat model combining SCI with cast immobilization (IMM) to more closely reproduce the unloading conditions experienced by SCI patients. Magnetic resonance imaging was used to monitor hindlimb muscles' cross-sectional area (CSA) after SCI, IMM alone, SCI combined with IMM (SCI+IMM), and in controls (CTR) over a period of 21 days. Soleus muscle tetanic force was measured in situ on day 21, and hindlimb muscles were harvested for histology. IMM alone produced a decrease in triceps surae CSA to 63.9±4.9% of baseline values within 14 days. In SCI, CSA decreased to 75.0±10.5% after 7 days, and recovered to 77.9±10.7% by day 21. SCI+IMM showed the greatest amount of atrophy (56.9±9.9% on day 21). In all groups, muscle mass and soleus tetanic force decreased in parallel, such that specific force was maintained. Extensor digitorum longus (EDL) and soleus fiber size decreased in all groups, particularly in SCI+IMM. We observed a significant degree of asymmetry in muscle CSA in SCI but not IMM. This effect increased between day 7 and 21 in SCI, but also in SCI+IMM, suggesting a minor dependence on muscle activity. SCI+IMM offers a clinically relevant model of SCI to investigate the mechanistic basis for skeletal muscle adaptations after SCI and develop therapeutic approaches.
PMCID: PMC3565549  PMID: 22985272
atrophy; immobilization; magnetic resonance imaging; SCI; skeletal muscle
22.  Activating HER2 mutations in HER2 gene amplification negative breast cancer 
Cancer discovery  2012;3(2):224-237.
Data from eight breast cancer genome sequencing projects identified 25 patients with HER2 somatic mutations in cancers lacking HER2 gene amplification. To determine the phenotype of these mutations, we functionally characterized thirteen HER2 mutations using in vitro kinase assays, protein structure analysis, cell culture and xenograft experiments. Seven of these mutations are activating mutations, including G309A, D769H, D769Y, V777L, P780ins, V842I, and R896C. HER2 in-frame deletion 755-759, which is homologous to EGFR exon 19 in-frame deletions, had a neomorphic phenotype with increased phosphorylation of EGFR or HER3. L755S produced lapatinib resistance, but was not an activating mutation in our experimental systems. All of these mutations were sensitive to the irreversible kinase inhibitor, neratinib. These findings demonstrate that HER2 somatic mutation is an alternative mechanism to activate HER2 in breast cancer and they validate HER2 somatic mutations as drug targets for breast cancer treatment.
PMCID: PMC3570596  PMID: 23220880
Genomics; Breast Cancer; Receptor Tyrosine Kinase; Oncogene
23.  Flos Lonicera Ameliorates Obesity and Associated Endotoxemia in Rats through Modulation of Gut Permeability and Intestinal Microbiota 
PLoS ONE  2014;9(1):e86117.
Background and Aim
Increasing evidence has indicated a close association of host-gut flora metabolic interaction with obesity. Flos Lonicera, a traditional herbal medicine, is used widely in eastern Asia for the treatment of various disorders. The aim of this study was to evaluate whether unfermented or fermented formulations of Flos Lonicera could exert a beneficial impact to combat obesity and related metabolic endotoxemia.
Obesity and metabolic endotoxemia were induced separately or together in rats through feeding a eight-week high fat diet either alone (HFD control group) or in combination with a single LPS stimulation (intraperitoneal injection, 0.75 mg/kg) (LPS control group). While, the mechanism of action of the Lonicera formulations was explored in vitro using RAW 264.7 and HCT 116 cell lines as models.
In cell-based studies, treatment with both unfermented Flos Lonicera (UFL) and fermented Flos Lonicera (FFL) formulations resulted in suppression of LPS-induced NO production and gene expression of vital proinflammatory cytokines (TNF-α, COX-2, and IL-6) in RAW 264.7 cells, reduced the gene expression of zonula occludens (ZO)-1 and claudin-1, and normalized trans epithelial electric resistance (TEER) and horseradish peroxidase (HRP) flux in LPS-treated HCT-116 cells. In an animal study, treatment of HFD as well as HFD+LPS groups with UFL or FFL resulted in a notable decrease in body and adipose tissue weights, ameliorated total cholesterol, HDL, triglyceride, aspartate transaminase and endotoxin levels in serum, reduced the urinary lactulose/mannitol ratio, and markedly alleviated lipid accumulation in liver. In addition, exposure of HFD as well as HFD+LPS groups with UFL or FFL resulted in significant alteration of the distribution of intestinal flora, especially affecting the population of Akkermansia spp. and ratio of Bacteroidetes and Firmicutes.
This evidence collectively demonstrates that Flos Lonicera ameliorates obesity and related metabolic endotoxemia via regulating distribution of gut flora and gut permeability.
PMCID: PMC3901675  PMID: 24475077
24.  Endocrine-Therapy-Resistant ESR1 Variants Revealed by Genomic Characterization of Breast-Cancer-Derived Xenografts 
Cell reports  2013;4(6):10.1016/j.celrep.2013.08.022.
To characterize patient-derived xenografts (PDXs) for functional studies, we made whole-genome comparisons with originating breast cancers representative of the major intrinsic subtypes. Structural and copy number aberrations were found to be retained with high fidelity. However, at the single-nucleotide level, variable numbers of PDX-specific somatic events were documented, although they were only rarely functionally significant. Variant allele frequencies were often preserved in the PDXs, demonstrating that clonal representation can be transplantable. Estrogen-receptor-positive PDXs were associated with ESR1 ligand-binding-domain mutations, gene amplification, or an ESR1/YAP1 translocation. These events produced different endocrine-therapy-response phenotypes in human, cell line, and PDX endocrine-response studies. Hence, deeply sequenced PDX models are an important resource for the search for genome-forward treatment options and capture endocrine-drug-resistance etiologies that are not observed in standard cell lines. The originating tumor genome provides a benchmark for assessing genetic drift and clonal representation after transplantation.
PMCID: PMC3881975  PMID: 24055055
25.  DAMP Molecule S100A9 Acts as a Molecular Pattern to Enhance Inflammation during Influenza A Virus Infection: Role of DDX21-TRIF-TLR4-MyD88 Pathway 
PLoS Pathogens  2014;10(1):e1003848.
Pathogen-associated molecular patterns (PAMPs) trigger host immune response by activating pattern recognition receptors like toll-like receptors (TLRs). However, the mechanism whereby several pathogens, including viruses, activate TLRs via a non-PAMP mechanism is unclear. Endogenous “inflammatory mediators” called damage-associated molecular patterns (DAMPs) have been implicated in regulating immune response and inflammation. However, the role of DAMPs in inflammation/immunity during virus infection has not been studied. We have identified a DAMP molecule, S100A9 (also known as Calgranulin B or MRP-14), as an endogenous non-PAMP activator of TLR signaling during influenza A virus (IAV) infection. S100A9 was released from undamaged IAV-infected cells and extracellular S100A9 acted as a critical host-derived molecular pattern to regulate inflammatory response outcome and disease during infection by exaggerating pro-inflammatory response, cell-death and virus pathogenesis. Genetic studies showed that the DDX21-TRIF signaling pathway is required for S100A9 gene expression/production during infection. Furthermore, the inflammatory activity of extracellular S100A9 was mediated by activation of the TLR4-MyD88 pathway. Our studies have thus, underscored the role of a DAMP molecule (i.e. extracellular S100A9) in regulating virus-associated inflammation and uncovered a previously unknown function of the DDX21-TRIF-S100A9-TLR4-MyD88 signaling network in regulating inflammation during infection.
Author Summary
The lung disease severity following influenza A virus (IAV) infection is dependent on the extent of inflammation in the respiratory tract. Severe inflammation in the lung manifests in development of pneumonia. Therefore, it is very critical to identify cellular factors and dissect the molecular/cellular mechanism controlling inflammation in the respiratory tract during IAV infection. Knowledge derived from these studies will be instrumental in development of therapeutics to combat the lung disease associated with IAV infection. Towards that end, in the current study we have identified a cellular factor S100A9 which is responsible for enhanced inflammation during IAV infection. In addition, we have characterized a signal transduction pathway involving various cellular receptors and signaling adaptors that are involved in mediating S100A9-dependent inflammatory response. Thus, our studies have illuminated a cellular/molecular mechanism that can be intervened by therapeutics to reduce and control IAV-associated lung inflammatory disease like pneumonia.
PMCID: PMC3879357  PMID: 24391503

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