Effect of metC mutation on Salmonella Gallinarum virulence and invasiveness in 1-day-old White Leghorn chickens

Shah, D.H.,Shringi, S.,Desai, A.R.,Heo, E.J.,Park, J.H.,Chae, J.S. Elsevier Scientific Pub. Co 2007 Veterinary microbiology Vol.119 No.2

Salmonella enterica serotype Gallinarum (S. Gallinarum) is the causative agent of fowl typhoid (FT) in chickens. FT is a severe systemic disease of chickens causing heavy economic losses to the poultry industry through mortality, reduced egg production and culling of precious breeding stocks. In this study, a metC (encoding cystathionine β lyase) mutant was produced from a virulent strain of S. Gallinarum by Mini-Tn5 insertional inactivation. The mutant was significantly attenuated in virulence for 1-day-old White Leghorn chickens. Inactivation of metC resulted in 10<SUP>4</SUP>-fold increase in the LD<SUB>50</SUB> when compared with the wild type parent. The metC mutant showed an in vivo competitiveness defect in the challenged chickens and significantly lower (P<0.01) bacterial burden in the reticuloendothelial organs when compared with the wild-type parent. These results indicate that metC gene is important for virulence of S. Gallinarum in chickens.

Mechanisms of antibiotic removal by nanofiltration membranes: Model development and application

Shah, A.D.,Huang, C.H.,Kim, J.H. Elsevier Scientific Pub. Co 2012 Journal of membrane science Vol.389 No.-

Nanofiltration (NF) membranes have been shown to effectively remove low-molecular-weight compounds, but predicting their rejection has posed challenges due to the fact that multiple mechanisms can be involved (e.g. adsorption, steric-hindrance effects, and electrostatic effects) that concurrently control removal. The objective of this study was to systematically evaluate which factors were responsible for steady-state rejection of selected antibiotics such as sulfamethoxazole (SMX) and carbadox (CDX) for three NF membranes of varying tightness through a unique modeling approach which accounts for the fact that these compounds bear distinctive acid-base speciation properties under varying pH conditions. Both the steric-hindrance/pore-diffusion model for neutral solutes along with the Donnan steric partitioning model for charged solutes were integrated together to predict overall rejection. This is the first known study to evaluate compound rejection of compounds that carry such unique speciation properties as a function of pH by using such a combined approach. Antibiotic rejection was found to vary with both pH and membrane tightness. Rejection controlled by charge repulsion effects was accurately predicted for both negatively charged solutes such as SMX<SUP>-</SUP> and CDX<SUP>-</SUP> and positively charged solutes such as SMX<SUP>+</SUP>. However, rejection controlled by steric-hindrance effects for neutral solutes either overestimated (e.g. SMX) or underestimated (e.g. CDX) rejection by up to 23%. These findings improve the understanding of which transport mechanisms influence rejection of both neutral and charged low-molecular-weight compounds by NF membranes so that removal can be better predicted.

ON THE ACTIVE CONTROL OF VORTEX SHEDDING

D. A. Shah,Y. T. Chew,Khir Johari 대한기계학회 1992 International Conference on Fluid Machinery Vol.1 No.1

Control of Fowl Typhoid Using Tissue Culture Medium Waste After Harvest of Korean Wild Ginseng <i>(Panax ginseng)</i>

Shah, D.H.,Seol, J.-W.,Park, S.-Y.,Ryu, K.-S.,Kwon, J.-T.,Cho, M.-R.,Park, J.-H.,Kang, C.-S.,Kang, H.-S.,Chae, J.-S. Elsevier 2005 The Journal of applied poultry research Vol.14 No.3

<P><B>Abstract</B></P> <P>Fowl typhoid (FT), caused by <I>Salmonella gallinarum</I> (SG), is responsible for heavy economic losses through morbidity, mortality, and reduced egg production to the poultry industry worldwide. The use of alternative medications to control FT is important in light of emergence of multiple drug-resistant strains of SG and the public's desire to have organically grown poultry. We report the efficient utilization of tissue culture medium waste after harvest of Korean wild ginseng (TCM-KWG) <I>(Panax ginseng)</I> as an alternative medicine in the control of FT. In a series of experiments performed in this study, we found that oral administration of TCM-KWG through drinking water significantly reduced the mortality, organ invasiveness, and fecal shedding of SG in 1-d-old chickens experimentally infected with virulent SG. The results were positively correlated with higher dose and longer duration of pretreatment with TCM-KWG in relation to reduction in mortality caused by FT. The results of this work indicate that the TCM-KWG may be used as a cost-effective and environmentally friendly alternative medicine to control and minimize the losses due to FT in chickens.</P>

Dielectric characteristics and thermal behaviour of terbium fumarate heptahydrate crystals

M.D. Shah,B. Want 한국물리학회 2015 Current Applied Physics Vol.15 No.2

Dielectric properties, ac conductivity and thermal characteristics of terbium fumarate heptahydrate crystals grown by gel diffusion method have been carried out. The real part of dielectric constant, dielectric loss and ac conductivity of the material have been measured as a function of temperature and frequency of the applied electric field. Dielectric constant, dielectric loss and ac conductivity of the title compound were systematically investigated, showing a hump at about 85 ℃, which could be attributed to water molecules in the crystal boundary. The dielectric anomaly exhibited by the material has been correlated with its thermal behaviour. The ac conductivity of the material obeys the Jonscher's power law relation; σ(ω) = σ0 + Aωs, with the temperature dependent power exponent s < 1. The ac conductivity of the compound has been found to increase with the increase in frequency. The material is suggested to show protonic conduction. The non-isothermal kinetics was used to evaluate the activation energy for the dehydration step of thermal decomposition of terbium fumarate heptahydrate by using the Coats -Redfern integral method.

A relative assessment of sub grid scale models for large eddy simulation of co-axial combustor

Rupesh D. Shah,Hanumanthappa Patil,Jyotirmay Banerjee 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.6

Large eddy simulation (LES) of a co-axial combustor is reported. Accuracy of LES depends on the ability of the sub-grid scale (SGS)models to predict the turbulent viscosity. The sensitivity of LES results for different SGS models is established for a coaxial annular combustor. The radial, axial and tangential velocity distribution predicted by four sub-grid scale models is compared with the experimental results of Sommerfeld and Qiu. It is observed that the flow physics is captured more accurately by WALE model as compared to other SGS models. The predictions of WALE model are closer to the experimental results for all stations in the flow domain.

Dephosphorylation Enables the Recruitment of 53BP1 to Double-Strand DNA Breaks

Lee, D.H.,Acharya, Sanket S.,Kwon, M.,Drane, P.,Guan, Y.,Adelmant, G.,Kalev, P.,Shah, J.,Pellman, D.,Marto, Jarrod A.,Chowdhury, D. Cell Press 2014 Molecular cell Vol.54 No.3

Excluding 53BP1 from chromatin is required to attenuate the DNA damage response during mitosis, yet the functional relevance and regulation of this exclusion are unclear. Here we show that 53BP1 is phosphorylated during mitosis on two residues, T1609 and S1618, located in its well-conserved ubiquitination-dependent recruitment (UDR) motif. Phosphorylating these sites blocks the interaction of the UDR motif with mononuclesomes containing ubiquitinated histone H2A and impedes binding of 53BP1 to mitotic chromatin. Ectopic recruitment of 53BP1-T1609A/S1618A to mitotic DNA lesions was associated with significant mitotic defects that could be reversed by inhibiting nonhomologous end-joining. We also reveal that protein phosphatase complex PP4C/R3β dephosphorylates T1609 and S1618 to allow the recruitment of 53BP1 to chromatin in G1 phase. Our results identify key sites of 53BP1 phosphorylation during mitosis, identify the counteracting phosphatase complex that restores the potential for DDR during interphase, and establish the physiological importance of this regulation.

100-kV Feedthrough for the Indian Test Facility (INTF) - Design and Analysis

Sejal Shah,D. Sharma,M. Bandyopadhyay,C. Rotti,G. Bansal,J. Joshi,D. Parmar,A. Chakraborty 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.8

The Indian Test Facility (INTF) high-voltage (HV) feedthrough has been designed to connectall the required feedlines carried by the transmission line from the HV deck to the beam source. It forms the primary vacuum boundary and provides 100-kV isolation for INTF beam operation. Thermomechanical and electrostatic analyses have been carried out to validate the design. Theobserved thermomechanical stress and deflections are within acceptable limits. The results arevalidated using Structural Design Criteria for In-vessel Components (SDC-IC) criteria. The presentmanuscript describes the design of and the analysis results for the INTF HV feedthrough.

Lower and Upper Gastrointestinal Symptoms Differ Between Individuals With Irritable Bowel Syndrome With Constipation or Chronic Idiopathic Constipation

Eric D Shah,Christopher V Almario,Brennan M R Spiegel,William D Chey 대한소화기 기능성질환∙운동학회 2018 Journal of Neurogastroenterology and Motility (JNM Vol.24 No.2

Background/Aims We evaluated the distribution of lower and upper gastrointestinal (GI) symptoms among individuals with irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) in a nationwide survey. Methods Individuals (≥ 18 years of age) were identified from a nationwide sample of > 70 000 United States adults. Participants completed the National Institutes of Health GI Patient Reported Outcomes Measurement Information System (NIH GI-PROMIS) questionnaire. Symptom frequency and intensity in the prior 7 days were assessed using validated PROMIS scores. Odds ratios (OR) with 95% confidence intervals (CI) were calculated to compare symptom prevalence in IBS-C vs CIC, and one-way ANOVA was used to assess differences in PROMIS scores. Regression analysis was performed to adjust for demographic variables. Results Nine hundred and seventy adults met eligibility criteria (275 with IBS-C, 734 with CIC). Demographics were similar among groups except for education, marital and employment status, and income. Adjusting for demographic differences, GI-PROMIS scores of global GI symptoms were higher in IBS-C (251.1; 95% CI, 230.0–273.1) compared to CIC (177.8; 95% CI 167.2–188.4) (P < 0.001). Abdominal pain was more prevalent (OR, 4.3; 95% CI, 2.9–6.6) and more severe (P = 0.007) in IBS-C. Constipation was more severe in IBS-C (P = 0.011). Incontinence was more common (OR, 2.9; 95% CI, 1.3–6.3) but just as severe (P = 0.389) in IBS-C versus CIC. Regarding upper GI symptoms, the prevalence of dysphagia, heartburn, and nausea were similar. However, IBS-C individuals had more severe heartburn (P = 0.001). Conclusion GI symptoms are generally more severe in IBS-C compared to CIC, however abdominal pain, bloating, and upper GI symptoms still commonly occur in CIC.

Estimating the Contribution of Acute Gastroenteritis to the Overall Prevalence of Irritable Bowel Syndrome

( Eric D Shah ),( Mark S Riddle ),( Christopher Chang ),( Mark Pimentel ) 대한소화기기능성질환·운동학회(구 대한소화관운동학회) 2012 Journal of Neurogastroenterology and Motility (JNM Vol.18 No.2

Background/Aims Recent studies reveal that acute gastroenteritis can precipitate irritable bowel syndrome (IBS) symptoms leading to the concept of post-infectious IBS. However, the overall contribution of gastroenteritis to the total IBS prevalence is unknown. In this exercise we try to estimate the contribution of gastroenteritis in IBS using the published literature and a longitudinal approach. Methods Existing literature was reviewed to determine the incidence of IBS after gastroenteritis, the rate of remission over time, data on rates of gastroenteritis in a given population and any patterns of resistance to these effects in human populations. This produced 3 models. The first assumed all humans were susceptible to gastroenteritis and its ability to produce IBS. The second assumed (using meta-analysis data) that 90% of humans in a given outbreak would be resistant to this effect. The third model used a high gastroenteritis exposure rate as might be seen in military deployment. Results In model 1, the prevalence was unrealistically high with an eventual steady state of 43.6% of the population affected by IBS. In a very conservative approach (model 2), steady state was achieved after 10 years to an overall prevalence of 8.9%. Interestingly, based on a high 1 year exposure rate such as military deployment, the maximum prevalence (steady state) was reached before 1 year suggesting high risk. Conclusions Although hypothetical in approach, based on conservative estimates in existing literature the contribution of gastroenteritis to the overall prevalence of IBS is substantial.