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author:("Patel, hendra")
1.  Identification of virulence associated loci in the emerging broad host range plant pathogen Pseudomonas fuscovaginae 
BMC Microbiology  2014;14(1):274.
Background
Pseudomonas fuscovaginae (Pfv) is an emerging plant pathogen of rice and also of other gramineae plants. It causes sheath brown rot disease in rice with symptoms that are characterized by brown lesions on the flag leaf sheath, grain discoloration and sterility. It was first isolated as a high altitude pathogen in Japan and has since been reported in several countries throughout the world. Pfv is a broad host range pathogen and very little is known about its virulence mechanisms.
Results
An in planta screen of 1000 random independent Tn5 genomic mutants resulted in the isolation of nine mutants which showed altered virulence. Some of these isolates are mutated for functions which are known to be virulence associated factors in other phytopathogenic bacteria (eg. pil gene, phytotoxins and T6SS) and others might represent novel virulence loci.
Conclusions
Being an emerging pathogen worldwide, the broad host range pathogen Pfv has not yet been studied for its virulence functions. The roles of the nine loci identified in the in planta screen are discussed in relation to pathogenicity of Pfv. In summary, this article reports a first study on the virulence of this pathogen involving in planta screening studies and suggests the presence of several virulence features with known and novel functions in the Pseudomonas group of bacteria.
Electronic supplementary material
The online version of this article (doi:10.1186/s12866-014-0274-7) contains supplementary material, which is available to authorized users.
doi:10.1186/s12866-014-0274-7
PMCID: PMC4237756  PMID: 25394860
2.  The Kiwifruit Emerging Pathogen Pseudomonas syringae pv. actinidiae Does Not Produce AHLs but Possesses Three LuxR Solos 
PLoS ONE  2014;9(1):e87862.
Pseudomonas syringae pv. actinidiae (Psa) is an emerging phytopathogen causing bacterial canker disease in kiwifruit plants worldwide. Quorum sensing (QS) gene regulation plays important roles in many different bacterial plant pathogens. In this study we analyzed the presence and possible role of N-acyl homoserine lactone (AHL) quorum sensing in Psa. It was established that Psa does not produce AHLs and that a typical complete LuxI/R QS system is absent in Psa strains. Psa however possesses three putative luxR solos designated here as PsaR1, PsaR2 and PsaR3. PsaR2 belongs to the sub-family of LuxR solos present in many plant associated bacteria (PAB) that binds and responds to yet unknown plant signal molecules. PsaR1 and PsaR3 are highly similar to LuxRs which bind AHLs and are part of the canonical LuxI/R AHL QS systems. Mutation in all the three luxR solos of Psa showed reduction of in planta survival and also showed additive effect if more than one solo was inactivated in double mutants. Gene promoter analysis revealed that the three solos are not auto-regulated and investigated their possible role in several bacterial phenotypes.
doi:10.1371/journal.pone.0087862
PMCID: PMC3909224  PMID: 24498215
3.  Correction: Quantitative Analysis of BTF3, HINT1, NDRG1 and ODC1 Protein Over-Expression in Human Prostate Cancer Tissue 
PLoS ONE  2014;9(1):10.1371/annotation/80c6bb6d-657b-46be-ba77-3de5d528c89e.
doi:10.1371/annotation/80c6bb6d-657b-46be-ba77-3de5d528c89e
PMCID: PMC3890231
4.  Cell Wall Degrading Enzyme Induced Rice Innate Immune Responses Are Suppressed by the Type 3 Secretion System Effectors XopN, XopQ, XopX and XopZ of Xanthomonas oryzae pv. oryzae 
PLoS ONE  2013;8(9):e75867.
Innate immune responses are induced in plants and animals through perception of Damage Associated Molecular Patterns. These immune responses are suppressed by pathogens during infection. A number of studies have focussed on identifying functions of plant pathogenic bacteria that are involved in suppression of Pathogen Associated Molecular Pattern induced immune responses. In comparison, there is very little information on functions used by plant pathogens to suppress Damage Associated Molecular Pattern induced immune responses. Xanthomonasoryzae pv. oryzae, a gram negative bacterial pathogen of rice, secretes hydrolytic enzymes such as LipA (Lipase/Esterase) that damage rice cell walls and induce innate immune responses. Here, we show that Agrobacterium mediated transient transfer of the gene for XopN, a X. oryzae pv. oryzae type 3 secretion (T3S) system effector, results in suppression of rice innate immune responses induced by LipA. A xopN- mutant of X. oryzae pv. oryzae retains the ability to suppress these innate immune responses indicating the presence of other functionally redundant proteins. In transient transfer assays, we have assessed the ability of 15 other X. oryzae pv. oryzae T3S secreted effectors to suppress rice innate immune responses. Amongst these proteins, XopQ, XopX and XopZ are suppressors of LipA induced innate immune responses. A mutation in any one of the xopN, xopQ, xopX or xopZ genes causes partial virulence deficiency while a xopN- xopX- double mutant exhibits a greater virulence deficiency. A xopN- xopQ- xopX- xopZ- quadruple mutant of X. oryzae pv. oryzae induces callose deposition, an innate immune response, similar to a X. oryzae pv. oryzae T3S- mutant in rice leaves. Overall, these results indicate that multiple T3S secreted proteins of X. oryzae pv. oryzae can suppress cell wall damage induced rice innate immune responses.
doi:10.1371/journal.pone.0075867
PMCID: PMC3784402  PMID: 24086651
5.  Role of Activating FcγR Gene Polymorphisms in Kawasaki Disease Susceptibility and Intravenous Immunoglobulin Response 
Background
A functional polymorphism in the inhibitory IgG-Fc receptor FcγRIIB influences intravenous immunoglobulin (IVIG) response in Kawasaki Disease (KD) a vasculitis preferentially affecting the coronary arteries in children. We tested the hypothesis that the polymorphisms in the activating receptors (Fcγ RIIA, Fcγ RIIIA and Fcγ RIIIB) also influence susceptibility, IVIG treatment response, and coronary artery disease (CAD) in KD patients.
Methods and Results
We genotyped polymorphisms in the activating FcγRIIA, FcγRIIIA and FcγRIIIB genes using pyrosequencing in 443 KD patients, including 266 trios and 150 single parent-child pairs, in northwest US and genetically determined race with 155 ancestry information markers. We used the FBAT program to test for transmission disequilibrium and further generated pseudo-sibling controls for comparisons to the cases. The FcγRIIA-131H variant showed an association with KD (p = 0.001) with ORadditive = 1.51 [1.16–1.96], p = 0.002) for the primary combined population, which persisted in both Caucasian (p = .04) and Asian (p = .01) subgroups and is consistent with the recent genome-wide association study. We also identified over-transmission of FcγRIIIB-NA1 among IVIG non-responders (p = 0.0002), and specifically to Caucasian IVIG non-responders (p = 0.007). Odds ratios for overall and Caucasian non-responders were respectively 3.67 [1.75–7.66], p = 0.0006 and 3.60 [1.34–9.70], p = 0.01. Excess NA1 transmission also occurred to KD with CAD (ORadditive = 2.13 [1.11–4.0], p = 0.02).
Conclusion
A common variation in FcγRIIA is associated with increased KD susceptibility. The FcγRIIIB-NA1, which confers higher affinity for IgG compared to NA2, is a determining factor for treatment response. These activating FcγRs play an important role in KD pathogenesis and mechanism of IVIG anti-inflammatory.
doi:10.1161/CIRCGENETICS.111.962464
PMCID: PMC3444514  PMID: 22565545
coronary disease; pediatrics; Kawasaki disease; IVIG treatment response; FcγR
6.  Bacterial LuxR solos have evolved to respond to different molecules including signals from plants 
A future challenge will be understanding the extensive communication that most likely takes place in bacterial interspecies and interkingdom signaling between plants and bacteria. A major bacterial inter-cellular signaling system in Gram-negative bacteria is LuxI/R quorum sensing (QS) based on the production (via the LuxI-family proteins) and detection (via the LuxR-family proteins) of N-acyl homoserine lactones (AHLs) signaling molecules. LuxR proteins which have the same modular structure of QS LuxRs but are devoid of a cognate LuxI AHL synthase are called solos. LuxR solos have been shown to be responsible to respond to exogenous AHLs produced by neighboring cells as well endogenously produced AHLs. It is now also evident that some LuxR proteins have evolved from the ability to binding AHLs and respond to other molecules/signals. For example, recent research has shown that a sub-family of LuxR solos responds to small molecules produced by plants. This indicates the presence of a uni-directional interkingdom signaling system occurring from plants to bacteria. In addition LuxR solos have now been also implicated to respond to endogenously produced signals which are not AHLs. In this Mini Review article we will discuss current trends and implications of the role of LuxR solos in bacterial responses to other signals using proteins related to AHL QS systems.
doi:10.3389/fpls.2013.00447
PMCID: PMC3824090  PMID: 24273546
quorum sensing; N-acyl homoserine lactones; interkingdom signaling; LuxR solos; plant signals
7.  Draft Genome Sequence of Pseudomonas fuscovaginae, a Broad-Host-Range Pathogen of Plants 
Journal of Bacteriology  2012;194(10):2765-2766.
Pseudomonas fuscovaginae was first reported as a pathogen of rice causing sheath rot in plants grown at high altitudes. P. fuscovaginae is now considered a broad-host-range plant pathogen causing disease in several economically important plants. We report what is, to our knowledge, the first draft genome sequence of a P. fuscovaginae strain.
doi:10.1128/JB.00341-12
PMCID: PMC3347198  PMID: 22535942
8.  Functional FcγRIIB Gene Variants Influence Intravenous Immunoglobulin (IVIG) Response in Kawasaki Disease (KD) Patients 
Capsule Summary
In Kawasaki Disease patients, the authors show associations between high-dose intravenous immunoglobulin (IVIG) response and a polymorphism in the FCγRIIB. This provides basis for defining the IVIG regulatory mechanisms and pharmacogenomic approach to IVIG therapy.
doi:10.1016/j.jaci.2011.04.027
PMCID: PMC3444515  PMID: 21601260
Kawasaki disease; IVIG treatment response; FcγR
9.  Triiodothyronine Supplementation in Infants and Children Undergoing Cardiopulmonary Bypass (TRICC) A Multicenter Placebo-Controlled Randomized Trial: Age Analysis 
Circulation  2010;122(11 Suppl):S224-S233.
Background
Triiodothyronine levels decrease in infants and children after cardiopulmonary bypass. We tested the primary hypothesis that triiodothyronine (T3) repletion is safe in this population and produces improvements in postoperative clinical outcome.
Methods and Results
The TRICC study was a prospective, multicenter, double-blind, randomized, placebo-controlled trial in children younger than 2 years old undergoing heart surgery with cardiopulmonary bypass. Enrollment was stratified by surgical diagnosis. Time to extubation (TTE) was the primary outcome. Patients received intravenous T3 as Triostat (n=98) or placebo (n=95), and data were analyzed using Cox proportional hazards. Overall, TTE was similar between groups. There were no differences in adverse event rates, including arrhythmia. Prespecified analyses showed a significant interaction between age and treatment (P=0.0012). For patients younger than 5 months, the hazard ratio (chance of extubation) for Triostat was 1.72. (P=0.0216). Placebo median TTE was 98 hours with 95% confidence interval (CI) of 71 to 142 compared to Triostat TTE at 55 hours with CI of 44 to 92. TTE shortening corresponded to a reduction in inotropic agent use and improvement in cardiac function. For children 5 months of age, or older, Triostat produced a significant delay in median TTE: 16 hours (CI, 7–22) for placebo and 20 hours (CI, 16–45) for Triostat and (hazard ratio, 0.60; P=0.0220).
Conclusions
T3 supplementation is safe. Analyses using age stratification indicate that T3 supplementation provides clinical advantages in patients younger than 5 months and no benefit for those older than 5 months.
Clinical Trial Registration
URL: http://www.clinicaltrials.gov. Unique identifier: NCT00027417.
doi:10.1161/CIRCULATIONAHA.109.926394
PMCID: PMC3090076  PMID: 20837917
cardiopulmonary bypass; congenital heart surgery; thyroid hormone
10.  Patient-Reported Validated Functional Outcome After Extraperitoneal Robotic-Assisted Nerve-Sparing Radical Prostatectomy 
Background and Objectives:
Erectile function after prostate surgery is an important criterion for patients when they are choosing a treatment modality for prostate cancer. Improved visualization, dexterity, and precision afforded by the da Vinci robot allow a precise dissection of the neurovascular bundles. We objectively assessed erectile function after robot-assisted extraperitoneal prostatectomy by using the SHIM (IIEF-5) validated questionnaire.
Methods:
Between July 2003 and September 2004, 150 consecutive men underwent da Vinci robot-assisted extraperitoneal radical prostatectomy for clinically localized prostate cancer. The IIEF-5 questionnaire was used to assess postoperative potency in 67 patients who were at least 6 months postsurgery. Erectile function was classified as impotent <11), moderate dysfunction (11 to 15), mild dysfunction (16 to 21), and potent (22 to 25). All patients used oral pharmacological assistance postprocedure.
Results:
Sixty-seven patients were available to complete the IIEF-5 questionnaire 6 months to 1 year postprostatectomy. Twelve patients were excluded from the study who abstained from all sexual activity after surgery for emotional or social reasons. Of the 55 patients evaluated, 22 (40%) were impotent, 3 (5.5%) had moderate erectile dysfunction (ED), 12 (21.8%) had mild ED, and 18 (32.7%) were fully potent. The table compares IIEF-5 scores with nerve-sparing status. Of patients who had bilateral nerve sparing, 28/45 (62.2%) had mild or no ED within 6 to 12 months postsurgery, and all expressed satisfaction with their current sexual function or rate of improvement after robotic prostatectomy.
Conclusion:
Robot-assisted extraperitoneal prostatectomy provides comparable outcomes to those of open surgery with regards to erectile function. Assessment of the ultimate maximal erectile function will require continued analysis, as this is likely to further improve beyond 6 to 12 months.
PMCID: PMC3015850  PMID: 18237507
Robotics; Prostatectomy; Sexual dysfunction; Postoperative complications
11.  Patient-Reported Validated Functional Outcome After Extraperitoneal Robotic-Assisted Nerve-Sparing Radical Prostatectomy 
Background and Objectives:
Erectile function after prostate surgery is an important criterion for patients when they are choosing a treatment modality for prostate cancer. Improved visualization, dexterity, and precision afforded by the da Vinci robot allow a precise dissection of the neurovascular bundles. We objectively assessed erectile function after robot-assisted extraperitoneal prostatectomy by using the SHIM (IIEF-5) validated questionnaire.
Methods:
Between July 2003 and September 2004, 150 consecutive men underwent da Vinci robot-assisted extraperitoneal radical prostatectomy for clinically localized prostate cancer. The IIEF-5 questionnaire was used to assess postoperative potency in 67 patients who were at least 6 months postsurgery. Erectile function was classified as impotent (<11), moderate dysfunction (11 to 15), mild dysfunction (16 to 21), and potent (22 to 25). All patients used oral pharmacological assistance postprocedure.
Results:
Sixty-seven patients were available to complete the IIEF-5 questionnaire 6 months to 1 year postprostatectomy. Twelve patients were excluded from the study who abstained from all sexual activity after surgery for emotional or social reasons. Of the 55 patients evaluated, 22 (40%) were impotent, 3 (5.5%) had moderate ED, 12 (21.8%) had mild ED, and 18 (32.7%) were fully potent. The table compares IIEF-5 scores with nerve-sparing status. Of patients who had bilateral nerve sparing, 28/45 (62.2%) had mild or no ED within 6 to 12 months postsurgery, and all expressed satisfaction with their current sexual function or rate of improvement after robotic prostatectomy.
Conclusion:
Robot-assisted extraperitoneal prostatectomy provides comparable outcomes to those of open surgery with regards to erectile function. Assessment of the ultimate maximal erectile function will require continued analysis, as this is likely to further improve beyond 6 to 12 months.
PMCID: PMC3015835  PMID: 17931513
Robotics; Prostatectomy; Sexual dysfunction; Postoperative complications

Results 1-12 (12)