Mycobacterium shottsii sp nov., a slowly growing species isolated from Chesapeake Bay striped bass (Morone saxatilis)

Slowly growing, non-pigmented mycobacteria were isolated from striped bass (Morone saxatilis) during an epizootic of mycobacteriosis in the Chesapeake Bay. Growth characteristics, acid-fastness and results of 16S rRNA gene sequencing were consistent with those of the genus Mycobacterium. A unique profile of biochemical reactions was observed among the 21 isolates. A single cluster of eight peaks identified by analysis of mycolic acids (HPLC) resembled those of reference patterns but differed in peak elution times from profiles of reference species of the Mycobacterium tuberculosis complex. One isolate (M175(T)) was placed within the slowly growing mycobacteria by analysis of aligned 16S rRNA gene sequences and was proximate in phylogeny to Mycobacterium ulcerans and Mycobacterium marinum. However, distinct nucleoticle differences were detected in the 16S rRNA gene sequence among M175(T), M. ulcerans and M. marinum (99-2% similarity). Isolate IM175(T) could be differentiated from other slowly growing, nonpigmented mycobacteria by its inability to grow at 37degreesC, production of niacin and urease, absence of nitrate reductase and resistance to isoniazid (1 mug ml(-1)), thiacetazone and thiophene-2-carboxylic hydrazide. Based upon these genetic and phenotypic differences, isolate IM175T (= ATCC 700981(T) = NCTC 13215(T)) is proposed as the type strain of a novel species, Mycobacterium shottsii sp. nov

Evolution of Mycobacterium ulcerans and other mycolactone-producing mycobacteria from a common Mycobacterium marinum progenitor

It had been assumed that production of the cytotoxic polyketide mycolactone was strictly associated with Mycobacterium ulcerans, the causative agent of Buruli ulcer. However, a recent study has uncovered a broader distribution of mycolactone-producing mycobacteria (MPM) that includes mycobacteria cultured from diseased fish and frogs in the United States and from diseased fish in the Red and Mediterranean Seas. All of these mycobacteria contain versions of the M. ulcerans pMUM plasmid, produce mycolactones, and show a high degree of genetic relatedness to both M. ulcerans and Mycobacterium marinum. Here, we show by multiple genetic methods, including multilocus sequence analysis and DNA-DNA hybridization, that all MPM have evolved from a common M. marinum progenitor to form a genetically cohesive group among a more diverse assemblage of M. marinum strains. Like M. ulcerans, the fish and frog MPM show multiple copies of the insertion sequence IS2404. Comparisons of pMUM and chromosomal gene sequences demonstrate that plasmid acquisition and the subsequent ability to produce mycolactone were probably the key drivers of speciation. Ongoing evolution among MPM has since produced at least two genetically distinct ecotypes that can be broadly divided into those typically causing disease in ectotherms (but also having a high zoonotic potential) and those causing disease in endotherms, such as humans

Mycobacterium pseudoshottsii sp nov., a slowly growing chromogenic species isolated from Chesapeake Bay striped bass (Morone saxatilis)

A group of slowly growing photochromogenic mycobacteria was isolated from Chesapeake Bay striped bass (Morone saxatilis) during an epizootic of mycobacteriosis. Growth characteristics, acid-fastness and 16S rRNA gene sequencing results were consistent with those of the genus Mycobacterium, Biochemical reactions, growth characteristics and mycolic acid profiles (HPLC) resembled those of Mycobacterium shottsii, a non-pigmented mycobacterium also isolated during the same epizootic. Sequencing of the 16S rRNA genes, the gene encoding the exported repeated protein (erp) and the gene encoding the 65 kDa heat-shock protein (hsp65) and restriction enzyme analysis of the hsp65 gene demonstrated that this group of isolates is unique. Insertion sequences associated with Mycobacterium ulcerans, IS2404 and IS2606, were detected by PCR. These isolates could be differentiated from other slowly growing pigmented mycobacteria by their inability to grow at 37 degrees C, production of niacin and urease, absence of nitrate reductase, negative Tween 80 hydrolysis and resistance to isoniazid (1 mu g ml(-1)), p-nitrobenzoic acid, thiacetazone and thiophene-2-carboxylic hydrazide. On the basis of this polyphasic study, it is proposed that these isolates represent a novel species, Mycobacterium pseudoshottsii sp. nov. The type strain, L15(T), has been deposited in the American Type Culture Collection as ATCC BAA-883(T) and the National Collection of Type Cultures (UK) as NCTC 13318(T)

Mycobacterial infections in striped bass (Morone saxatilis) from Delaware Bay

Much of what is known of mycobacteriosis in wild striped bass from the mid-Atlantic region of the United States is based on our observations from Chesapeake Bay and its tributaries, where high infection prevalence and lesioned fish are frequently observed. Comparatively, the occurrence and severity of mycobacteriosis in striped bass from watersheds adjacent to Chesapeake Bay are relatively unknown. This study represents the first report on mycobacterial infection in striped bass harvested from two sites in Delaware Bay.https://scholarworks.wm.edu/vimsbooks/1082/thumbnail.jp

The social production of substance abuse and HIV/HCV risk: an exploratory study of opioid-using immigrants from the former Soviet Union living in New York City

<p>Abstract</p> <p>Background</p> <p>Several former Soviet countries have witnessed the rapid emergence of major epidemics of injection drug use (IDU) and associated HIV/HCV, suggesting that immigrants from the former Soviet Union (FSU) may be at heightened risk for similar problems. This exploratory study examines substance use patterns among the understudied population of opioid-using FSU immigrants in the U.S., as well as social contextual factors that may increase these immigrants' susceptibility to opioid abuse and HIV/HCV infection.</p> <p>Methods</p> <p>In-depth interviews were conducted with 10 FSU immigrants living in New York City who initiated opioid use in adolescence or young adulthood, and with 6 drug treatment providers working with this population. Informed by a grounded theory approach, interview transcripts were inductively coded and analyzed to identify key themes.</p> <p>Results</p> <p>The "trauma" of the immigration/acculturation experience was emphasized by participants as playing a critical role in motivating opioid use. Interview data suggest that substance use patterns formed in the high-risk environment of the FSU may persist as behavioral norms within New York City FSU immigrant communities - including a predilection for heroin use among youth, a high prevalence of injection, and a tolerance for syringe sharing within substance-using peer networks. Multiple levels of social context may reproduce FSU immigrants' vulnerability to substance abuse and disease such as: peer-based interactional contexts in which participants typically used opioids; community workplace settings in which some participants were introduced to and obtained opioids; and cultural norms, with roots in Soviet-era social policies, stigmatizing substance abuse which may contribute to immigrants' reluctance to seek disease prevention and drug treatment services.</p> <p>Conclusion</p> <p>Several behavioral and contextual factors appear to increase FSU immigrants' risk for opioid abuse, IDU and infectious disease. Further research on opioid-using FSU immigrants is warranted and may help prevent increases in HIV/HCV prevalence from occurring within these communities.</p

The actin-myosin regulatory MRCK kinases: regulation, biological functions and associations with human cancer

The contractile actin-myosin cytoskeleton provides much of the force required for numerous cellular activities such as motility, adhesion, cytokinesis and changes in morphology. Key elements that respond to various signal pathways are the myosin II regulatory light chains (MLC), which participate in actin-myosin contraction by modulating the ATPase activity and consequent contractile force generation mediated by myosin heavy chain heads. Considerable effort has focussed on the role of MLC kinases, and yet the contributions of the myotonic dystrophy-related Cdc42-binding kinases (MRCK) proteins in MLC phosphorylation and cytoskeleton regulation have not been well characterized. In contrast to the closely related ROCK1 and ROCK2 kinases that are regulated by the RhoA and RhoC GTPases, there is relatively little information about the CDC42-regulated MRCKα, MRCKβ and MRCKγ members of the AGC (PKA, PKG and PKC) kinase family. As well as differences in upstream activation pathways, MRCK and ROCK kinases apparently differ in the way that they spatially regulate MLC phosphorylation, which ultimately affects their influence on the organization and dynamics of the actin-myosin cytoskeleton. In this review, we will summarize the MRCK protein structures, expression patterns, small molecule inhibitors, biological functions and associations with human diseases such as cancer

Training in childhood obesity management in the United States: a survey of pediatric, internal medicine-pediatrics and family medicine residency program directors

<p>Abstract</p> <p>Background</p> <p>Information about the availability and effectiveness of childhood obesity training during residency is limited.</p> <p>Methods</p> <p>We surveyed residency program directors from pediatric, internal medicine-pediatrics (IM-Peds), and family medicine residency programs between September 2007 and January 2008 about childhood obesity training offered in their programs.</p> <p>Results</p> <p>The response rate was 42.2% (299/709) and ranged by specialty from 40.1% to 45.4%. Overall, 52.5% of respondents felt that childhood obesity training in residency was extremely important, and the majority of programs offered training in aspects of childhood obesity management including prevention (N = 240, 80.3%), diagnosis (N = 282, 94.3%), diagnosis of complications (N = 249, 83.3%), and treatment (N = 242, 80.9%). However, only 18.1% (N = 54) of programs had a formal childhood obesity curriculum with variability across specialties. Specifically, 35.5% of IM-Peds programs had a formal curriculum compared to only 22.6% of pediatric and 13.9% of family medicine programs (p < 0.01). Didactic instruction was the most commonly used training method but was rated as only somewhat effective by 67.9% of respondents using this method. The most frequently cited significant barrier to implementing childhood obesity training was competing curricular demands (58.5%).</p> <p>Conclusions</p> <p>While most residents receive training in aspects of childhood obesity management, deficits may exist in training quality with a minority of programs offering a formal childhood obesity curriculum. Given the high prevalence of childhood obesity, a greater emphasis should be placed on development and use of effective training strategies suitable for all specialties training physicians to care for children.</p

Condom Negotiations among Female Sex Workers in the Philippines: Environmental Influences

BackgroundSocial and structural influences of condom negotiation among female sex workers (FSWs) remain understudied. This study assesses environmental and individual factors associated with condom negotiation among FSWs at high risk for acquiring HIV in a large urban setting of Metro Manila, Philippines.MethodsFemale bar/spa workers (N = 498), aged 18 and over, underwent interview-led surveys examining their sexual health practices in the context of their risk environments. Data were collected from April 2009-January 2010 from 54 venues. Multiple logistic regressions were conducted to assess socio-behavioral factors (e.g., age, education, length of time employed as an entertainer, and alcohol/drug use) and socio-structural factors (e.g., venue-level peer/manager support, condom rule/availability, and sex trafficking) associated with condom negotiation, adjusting for individuals nested within venues.ResultsOf 142 FSWs who traded sex in the previous 6 months (included in the analysis), 24% did not typically negotiate condom use with venue patrons. Factors in the physical environment--trafficked/coerced into work (AOR = 12.92, 95% CI = 3.34-49.90), economic environment--sex without a condom to make more money (AOR = 1.52, 95% CI 1.01-2.30), policy environment--sex without a condom because none was available (AOR = 2.58, 95% CI = 1.49-4.48), and individual risk--substance use (AOR = 2.36, 95% CI = 1.28-4.35) were independently associated with FSWs' lack of condom negotiation with venue patrons.ConclusionsFactors in the physical, economic, and policy environments, over individual (excepting substance use) and social level factors, were significantly associated with these FSWs' condom negotiations in the Philippines. Drawing upon Rhodes' risk environment framework, these results highlight the need for policies that support safer sex negotiations among sex workers in the context of their risk environments. Interventions should reduce barriers to condom negotiation for FSWs trafficked/coerced into their work, substance using, and impacted by economic conditions and policies that do not support condom availability

Mining expressed sequence tags identifies cancer markers of clinical interest

BACKGROUND: Gene expression data are a rich source of information about the transcriptional dis-regulation of genes in cancer. Genes that display differential regulation in cancer are a subtype of cancer biomarkers. RESULTS: We present an approach to mine expressed sequence tags to discover cancer biomarkers. A false discovery rate analysis suggests that the approach generates less than 22% false discoveries when applied to combined human and mouse whole genome screens. With this approach, we identify the 200 genes most consistently differentially expressed in cancer (called HM200) and proceed to characterize these genes. When used for prediction in a variety of cancer classification tasks (in 24 independent cancer microarray datasets, 59 classifications total), we show that HM200 and the shorter gene list HM100 are very competitive cancer biomarker sets. Indeed, when compared to 13 published cancer marker gene lists, HM200 achieves the best or second best classification performance in 79% of the classifications considered. CONCLUSION: These results indicate the existence of at least one general cancer marker set whose predictive value spans several tumor types and classification types. Our comparison with other marker gene lists shows that HM200 markers are mostly novel cancer markers. We also identify the previously published Pomeroy-400 list as another general cancer marker set. Strikingly, Pomeroy-400 has 27 genes in common with HM200. Our data suggest that a core set of genes are responsive to the deregulation of pathways involved in tumorigenesis in a variety of tumor types and that these genes could serve as transcriptional cancer markers in applications of clinical interest. Finally, our study suggests new strategies to select and evaluate cancer biomarkers in microarray studies