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Background Mycobacterium abscessus , an emerging pathogen in healthcare settings, has rarely been associated with community outbreaks. During February–May 2013, Idaho public health officials and pediatric infectious disease physicians investigated an outbreak of M abscessus skin infections in children whose only common exposure was an indoor wading pool. Methods Healthcare providers and parents reported possible M abscessus cases. We used a standardized questionnaire to interview parents of affected children. Clinical specimens were submitted for mycobacterial examination. We conducted an environmental investigation of the pool. Microbial isolates from clinical and environmental samples were identified by sequencing polymerase chain reaction amplicons and underwent pulsed-field gel electrophoresis. Results Twelve cases were identified. Specimens from 4 of 7 children grew M abscessus or Mycobacterium abscessus/Mycobacterium chelonae. Ten (83%) of 12 children were female; median age was 3 years (range, 2 to 6 years); and all were immunocompetent. Pool maintenance did not fully comply with Idaho state rules governing pool operation. Mycobacterium abscessus / chelonae was isolated from pool equipment. Pulsed-field gel electrophoresis composite patterns were 87% similar between isolates from the pool ladder and 1 patient, and they were 90% similar between isolates from 2 patients. Environmental remediation included hyperchlorination, scrubbing and disinfection of pool surfaces, draining the pool, and replacement of worn pool materials. Conclusions Immunocompetent children acquired M abscessus cutaneous infection involving hands and feet after exposure to a wading pool. Environmental remediation and proper pool maintenance likely halted transmission. Medical and public health professionals' collaboration effectively detected and controlled an outbreak caused by an emerging recreational waterborne pathogen. [ABSTRACT FROM AUTHOR]

Background: Brucellosis, a zoonosis caused by the genus Brucella, has been eradicated in Northern Europe, Australia, the USA and Canada, but remains endemic in most areas of the world. The strain and biovar typing of Brucella field samples isolated in outbreaks is useful for tracing back source of infection and may be crucial for discriminating naturally occurring outbreaks versus bioterrorist events, being Brucella a potential biological warfare agent. In the last years MLVA-16 has been described for Brucella spp. genotyping. The MLVA band profiles may be resolved by different techniques i.e. the manual agarose gels, the capillary electrophoresis sequencing systems or the microfluidic Lab-on-Chip electrophoresis. In this paper we described a high throughput system of MLVA-16 typing for Brucella spp. by using of the microfluidics technology. Results: The Caliper LabChip 90 equipment was evaluated for MLVA-16 typing of sixty-three Brucella samples. Furthermore, in order to validate the system, DNA samples previously resolved by sequencing system and Agilent technology, were de novo genotyped. The comparison of the MLVA typing data obtained by the Caliper equipment and those previously obtained by the other analysis methods showed a good correlation. However the outputs were not accurate as the Caliper DNA fragment sizes showed discrepancies compared with real data and a conversion table from observed to expected data was created. Conclusion: In this paper we described the MLVA-16 using a rapid, sophisticated microfluidics technology for detection of amplification product sizes. The comparison of the MLVA typing data produced by Caliper LabChip 90 system with the data obtained by different techniques showed a general concordance of the results. Furthermore this platform represents a significant improvement in terms of handling, data acquiring, computational efficiency and rapidity, allowing to perform the strain genotyping in a time equal to one sixth respect to other microfluidics systems as e.g. the Agilent 2100 bioanalyzer. Finally, this platform can be considered a valid alternative to standard genotyping techniques, particularly useful dealing with a large number of samples in short time. These data confirmed that this technology represents a significative advancement in high-throughput accurate Brucella genotyping. [ABSTRACT FROM AUTHOR]

Serovar identification of clinical isolates of Leptospira is generally not performed on a routine basis, yet the identity of an infecting serovar is valuable from both epidemiologic and public health standpoints. Only a small number of reference laboratories worldwide have the capability to perform the cross agglutinin absorption test (CAAT), the reference method for serovar identification. Pulsed-field gel electrophoresis (PFGE) is an alternative method to CAAT that facilitates rapid identification of leptospires to the serovar level. We employed PFGE to evaluate 175 isolates obtained from humans and animals submitted to the Centers for Disease Control and Prevention (CDC) between 1993 and 2007. PFGE patterns for each isolate were generated using the NotI restriction enzyme and compared to a reference database consisting of more than 200 reference strains. Of the 175 clinical isolates evaluated, 136 (78%) were identified to the serovar level by the database, and an additional 27 isolates (15%) have been identified as probable new serovars. The remaining isolates yet to be identified are either not represented in the database or require further study to determine whether or not they also represent new serovars. PFGE proved to be a useful tool for serovar identification of clinical isolates of known serovars from different geographic regions and a variety of different hosts and for recognizing potential new serovars. [ABSTRACT FROM AUTHOR]

In this article the author discusses the prevention the transmission of Clostridium difficile strain or known as the North American pulsed-field gel electrophoresis type I (NAP1) or the polymerase chain reaction ribotype 027 in the U.S. The author is critical on the effect of outbreaks which challenges for infection control programs in long term care facilities and programs in hospitals. Also discussed are the major sources of transmission.

The article summarizes the results of an investigation concerning the multistate outbreak of human Salmonella Typhimurium infections connected with aquatic frogs during 2009 in the U.S. The cases identified by the Utah Department of Health all had isolates indistinguishable by pulsed field gas electrophoresis. The investigation commenced with interviews of salmonellosis patients about exposures in the week prior to illness onset. The likely source of transmission in the outbreak was contact with water from the aquariums of the frogs.

Castor bean (Ricinus communis L.) seeds serve as raw material for the production of nonedible oil used in medicine and industry, whereas the presence of allergenic and toxic proteins in the residue left after oil extraction precludes the use of this protein-rich by-product in animal feeding. To better understand the enzymes involved in the biosynthesis and degradation of fatty acids and to identify proteins with toxic/anti-nutritional properties, extracts of developing and germinating seeds were prepared and prefractionated according to solubility properties of the proteins. An enriched plastid organelle fraction embracing mostly plastids and mitochondria was also prepared. Two-dimensional electrophoresis (2DE) reference maps of these fractions were obtained from which nearly 400 proteins were identified by matrix-assisted laser desorption ionization-time of flight-time of flight (MALDI-TOF-TOF) mass spectrometry after a search in a National Center for Biotechnology Information (NCBI) database and in an expressed sequence tag (EST) primary bank prepared from a cDNA library of developing seeds. These proteomics techniques resulted in the identification of several classes of seed reserve proteins such as 2S albumins, legumin-like and seed storage proteins, as well as other proteins of plastidial or mitochondrial functions and proteins involved in plant defense against biotic and abiotic stresses. It is expected that the collected data will facilitate the application of genetic techniques to improve the quality/profile of castor seed fatty acids, and pave the way for a rational approach to inactivate allergenic and toxic proteins, allowing the use of castor bean meal in animal feeding. [ABSTRACT FROM AUTHOR]

Ampicillin-resistant (Ampr) Salmonella enterica isolates (n = 344) representing 32 serotypes isolated from retail meats from 2002 to 2006 were tested for susceptibility to 21 other antimicrobial agents and screened for the presence of five beta-lactamase gene families (blaCMY, blaTEM, blaSHV, blaOXA, and blaCTX-M) and class 1 integrons. Among the Ampr isolates, 66.9% were resistant to five or more antimicrobials and 4.9% were resistant to 10 or more antimicrobials. Coresistance to other β-lactams was noted for amoxicillin-clavulanic acid (55.5%), ceftiofur (50%), cefoxitin (50%), and ceftazidime (24.7%), whereas less than 5% of isolates were resistant to piperacillin-tazobactam (4.9%), cefotaxime (3.5%), ceftriaxone (2%), and aztreonam (1.2%). All isolates were susceptible to cefepime, imipenem, and cefquinome. No Salmonella producing extended-spectrum beta-lactamases was found in this study. Approximately 7% of the isolates displayed a typical multidrug-resistant (MDR)-AmpC phenotype, with resistance to ampicillin, chloramphenicol, streptomycin, sulfonamide, tetracycline, plus resistance to amoxicillin-clavulanic acid, cefoxitin, and ceftiofur and with decreased susceptibility to ceftriaxone (MIC 4 μg/ml). Pulsed-field gel electrophoresis results showed that several MDR clones were geographically dispersed in different types of meats throughout the five sampling years. Additionally, 50% of the isolates contained blaCMY, 47% carried blaTEM-1, and 2.6% carried both genes. Only 15% of the isolates harbored class I integrons carrying various combinations of aadA, aadB, and dfrA gene cassettes. The blaCMY, blaTEM, and class 1 integrons were transferable through conjugation and/or transformation. Our findings indicate that a varied spectrum of coresistance traits is present in Ampr Salmonella strains in the meat supply of the United States, with a continued predominance of blaCMY and blaTEM genes in β-lactam-resistant isolates. [ABSTRACT FROM AUTHOR]

Objective--To evaluate the usefulness of an antibody detection ELISA and protein electrophoresis (PE) for diagnosing Encephalitozoon cuniculi (ECUN) infection in pet rabbits. Animals--203 pet rabbits. Procedures--Serum and plasma samples from pet rabbits were submitted from veterinary clinics within the United States. Participating veterinarians completed a questionnaire that was used to classify rabbits as clinically normal (n=33), suspected of having an ECUN infection (103), or clinically abnormal but not suspected of having an ECUN infection (67). An ELISA for detection of serum or plasma IgG against ECUN was developed by use of commercially available reagents. Results of the ELISA and PE were used to detect ECUN infection. Results--A high seroprevalence of antibody against ECUN was detected in all 3 groups of rabbits. In rabbits suspected of having an ECUN infection, the mean IgG titer was 1.7 times as high as the values in the other rabbit groups. Rabbits suspected of having an ECUN infection and those that were simply clinically abnormal had a higher concentration of γ-globulins than clinically normal rabbits. This increase in globulins concentration was accompanied by a decrease in the albumin-to-globulin ratio. Results of the ELISA and PE were significantly different between clinically normal rabbits and those suspected of having an ECUN infection. Conclusions and Clinical Relevance--The combination of an ELISA and PE may aid in the diagnosis of ECUN infection in pet rabbits. Impact for Human Medicine--Because ECUN is a potential zoonotic agent, diagnostic methods for pet rabbits need to be improved to protect human health. [ABSTRACT FROM AUTHOR]

Background. Knowledge of the clinical features of infections caused by Escherichia coli strains that produce plasmid-mediated AmpC β-lactamase is limited. Of the several groups of plasmid-mediated AmpC β-lactamases, CMY-type β-lactamase is the most common in the United States. Methods. We prospectively identified patients infected or colonized with E. coli strains that produce CMY-type β-lactamase, and we collected clinical data over a 7-month period. A retrospective cohort study was performed to identify features associated with these cases. Patients with extended-spectrum β-lactamase-producing E. coli were used as a control group. Pulsed-field gel electrophoresis, plasmid analysis, and phylogenetic typing were performed. Results. Twenty-two patients with infection or colonization due to CMY-type β-lactamase-producing E. coli and 25 patients with infection or colonization due to extended-spectrum β-lactamase-producing E. coli were identified. The demographic characteristics of the patients were similar in both cohorts. Patients with CMY-type β-lactamase-producing E. coli were significantly more likely to have symptomatic infection than were patients with extended-spectrum β-lactamase-producing E. coli (Pp.028). The CMY-type β-lactamase was identified as CMY-2 or its variants. Ninety-four percent of the CMY-type β-lactamase-producing isolates belonged to E. coli phylogenetic groups B2 and D, which are associated with virulence. Many of the isolates shared similar plasmid profiles, whereas the pulsed-field gel electrophoresis profiles were diverse. Co-resistance to non-β-lactam antimicrobials was common. Conclusion. In Pittsburgh, Pennsylvania, CMY-type β-lactamase-producing E. coli strains are almost as common as extended-spectrum β-lactamase-producing E. coli strains, and they cause symptomatic infection in the majority of cases. [ABSTRACT FROM AUTHOR]

Biological invasions can be substantially influenced by the genetic sampling associated with a species' introduction. As a result, we assessed the genetic and evolutionary consequences of the entry and spread of the invasive grass Bromus tectorurn (cheatgrass) across the United States midcontinent through an analysis of 54 populations, using enzyme electrophoresis. On average, these populations display 1.04 alleles per locus (A), 4.1% percent polymorphic loci per population (%P) and an expected mean heterozygosity (Hexp) value of 0.009. Heterozygotes, which have been rarely reported for B. tectorum in North America, occur in three populations in the midcontinent and are likely novel multilocus genotypes that arose postimmigration. The midcontinent distribution of multilocus genotypes suggests that plant immigrants came directly from either the native range or the eastern United States, or both. Continued dispersal of preadapted genotypes and the assembly of populations that are genetic admixtures may enhance this invasion by increasing both the genetic diversity within populations and the selection of novel genotypes arising from occasional outcrossing. The potential for postimmigration evolution in most species points to the largely unrecognized need to block the introduction of new, potentially aggressive genotypes of an alien species already in the United States. [ABSTRACT FROM AUTHOR]

We compared 581 Salmonella enterica serotype Schwarzengrund isolates from persons, food, and food animals in Denmark, Thailand, and the United States by antimicrobial drug susceptibility and pulsed-field gel electrophoresis (PFGE) typing. Resistance, including resistance to nalidixic acid, was frequent among isolates from persons and chickens in Thailand, persons in the United States, and food imported from Thailand to Denmark and the United States. A total of 183 PFGE patterns were observed, and 136 (23.4%) isolates had the 3 most common patterns. Seven of 14 isolates from persons in Denmark had patterns found in persons and chicken meat in Thailand; 22 of 390 human isolates from the United States had patterns found in Denmark and Thailand. This study suggests spread of multidrug-resistant S. Schwarzengrund from chickens to persons in Thailand, and from imported Thai food products to persons in Denmark and the United States. [ABSTRACT FROM AUTHOR]

Tularemia in the United States is caused by 2 subspecies of Francisella tularensis, subspecies tularensis (type A) and subspecies holarctica (type B). We compared clinical and demographic features of human tularemia cases from 1964 to 2004 from 39 states in which an isolate was recovered and subtyped. Our data indicate that type A and type B infections differ with respect to affected populations, anatomic site of isolation, and geographic distribution. Molecular subtyping with pulsed-field gel electrophoresis further defined 2 subpopulations of type A (type A-east and type A-west) that differ with respect to geographic distribution, disease outcome, and transmission. Our data suggest that type A-west infections are less severe than either type B or type A-east infections. Through a combined epidemiologic and molecular approach to human cases of tularemia, we provide new insights into the disease for future investigation. [ABSTRACT FROM AUTHOR]

Panicle blight of rice (Oryza saliva), caused by the bacterium Burkholderia glumae, is one of the most important new diseases in rice production areas of the southern United States. In this study, pathogenic strains were isolated from diseased panicles in Arkansas rice fields and examined using the Biolog GN microplate system, whole cell fatty acid methyl ester analysis (FAME), rep-polymerase chain reaction (PCR) genomic DNA fingerprinting, and 16S-23S ribosomal DNA (rDNA) intergenic transcribed spacer (ITS) sequence analysis. The B. glumae isolates from Arkansas can be divided into two major groups, but their genetic diversity was relatively low as revealed by 16S-23S rDNA ETS sequence analysis. Since no practical method existed, up to now, for testing the presence of B. glumae in rice seeds, we have developed in this study a real-time PCR method that is effective in detecting and identifying the pathogen in seed lots and in whole plants. The specific PCR primers were designed based on the 16S-23S rDNA ITS sequence of several representative isolates from Arkansas and Japan. This method is highly sensitive, rapid, and reliable, and has great potential for analyzing large numbers of samples without the need for DNA extraction or agarose gel electrophoresis. Although vertical resistance has not been observed among tested rice cultivars, LM-1 and Drew exhibited considerable resistance to B. glumae infection based on disease lesion size and the bacterial growth in planta. [ABSTRACT FROM AUTHOR]

Background. Multidrug-resistant Salmonella enteriea serotype Typhimurium Definitive Type 104 (DT104) emerged in the 1990s and is associated with greater clinical severity than pansusceptible S. Typhimurium. Although infection with DT1O4 is common in the United States, it is rarely associated with outbreaks. From October to December 2003, a cluster of DT104 infections with indistinguishable pulsed-field gel electrophoresis patterns was identified in the northeastern United States. Methods. A case-control study that assessed exposures compared case patients to age- and geography-matched control subjects. Information on consumer purchasing and grocery store suppliers was used to trace the implicated food to its source. Results. We identified 58 case patients in 9 states by pulsed-field gel electrophoresis. Representative isolates were phage type DT104 and were resistant to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (R-type ACSSuT). Of 27 patients interviewed for the case-control study, 41% were hospitalized (median duration of hospitalization, 4 days). Compared with 71 healthy control subjects, case patients had more medical comorbidities (matched odds ratio, 4.3; 95% confidence interval, 1.5-12.7). Illness was associated with consuming store-bought ground beef prepared as hamburgers at home (matched odds ratio, 5.3; 95% confidence interval, 1.9-15.3) and with eating raw ground beef (P ⩽ .001). Seven case patients (27%), but no control subjects, ate raw ground beef Product traceback linked cases to a single large ground beef manufacturer previously implicated in a multistate outbreak of highly drug-resistant Salmonella enterica Newport infections in 2002. Conclusions. This first multistate outbreak of highly drug-resistant S. Typhimurium DT104 infection associated with ground beef highlights the need for enhanced animal health surveillance and infection control, prudent use of antimicrobials for animals, improved pathogen reduction during processing, and better product tracking and consumer education. [ABSTRACT FROM AUTHOR]

Objective-To compare molecular typing methods for the differentiation of Salmonella enterica serovar Enteritidis phage type (PT) 4 isolates that allowed for the determination of their genetic relatedness. Sample Population-27 Salmonella Enteritidis PT 4 strains isolated in the United States and Europe. Procedure-Several molecular typing methods were performed to assess their ability to genetically differentiate among Salmonella Enteritidis PT 4 isolates. Results of pulse-field gel electrophoresis (PFGE), repetitive polymerase chain reaction (POR) assay, 16S rANA gene sequencing, random amplification of polymorphic DNA (RAPD), PCR-restriction fragment length polymorphism of 16S rRNA, and antimicrobial susceptibility were evaluated. Results-Compared with results for other techniques, results for the RAPD typing method with the RAPD1 primer reveal that it was the most discriminatory fingerprinting technique, and it allowed us to cluster Salmonella Enteritidis PT 4 isolates on the basis of their genetic similarity. Conclusions and Clinical Relevance-This study revealed the value of RAPD with the RAPD1 primer as a tool for epidemiologic investigations of Salmonella Enteritidis PT 4. It can be used in conjunction with PFGE and phage typing to determine the genetic relatedness of Salmonella Enteritidis isolates involved in outbreaks of disease. A reliable and highly discriminatory method for epidemiologic investigations critical to allow investigators to identify the source of infections and consequently prevent the spread of Salmonella Enteritidis PT 4. [ABSTRACT FROM AUTHOR]

Describes the use of comparative genomics in eukaryotic regulatory element conservation analysis and identification in the U.S. Mediation of the CD28 stimulation in T cells; Use of the electrophoretic mobility shift assays and nuclease protection assays; Factors influencing the sequences of yeast species.

Discusses the multistate outbreaks of Salmonella serotype Poona infections associated with eating cantaloupe imported from Mexico in the spring of consecutive years during 2000-2002. Background on pulsed-field gel electrophoresis; Number of cases reported in the U.S.; Information on the traceback investigations of cantaloupe purchased by patients, conducted by the U.S. Food and Drug Administration.

We investigated the breeding system and interfertility of both subspecies of Asclepias incarnata. We performed hand-pollinations in the glasshouse to compare fruit-set from self- vs. cross-pollinations and to assess interfertility in crosses between the subspecies. We also used horizontal starch-gel electrophoresis to infer mating-system parameters from open-pollinated progeny arrays in three natural populations over two consecutive years. Plants of ssp. incarnata were about 1/6 as likely to mature hand self-pollinated fruits as were ssp. pulchra plants. Furthermore, plants varied significantly in both self- and cross-fertility. Fertile offspring resulted from intersubspecific crosses, but hybrid plants showed reduced pollen fertility relative to parental plants, which is similar to what has been reported for wider hybrid crosses among milkweeds. Reduced pollen fertility in hybrids, along with geographical barriers, may contribute to maintaining subspecific differentiation. Based on allozyme markers, naturally pollinated populations were largely outcrossed (tm ranged from 0.881 to 0.986). Plants varied significantly with respect to outcrossed male fertility (rp ranged from 0.186 to 0.396) but not self-fertility (rt was not significantly different from 0). Outcrossing rate did not differ significantly among populations or between years. We found swamp milkweed to be neither fully self-compatible nor self-incompatible, which adds to growing evidence of the complexity of milkweed breeding systems. Variation in frequencies of alleles modifying the expression of the self-incompatibility system could explain some of this complexity. [ABSTRACT FROM AUTHOR]

The article discusses a formal planning process undertaken by the National Human Genome Research Institute (NHGRI) of the U.S. National Institutes of Health that will spearhead technological platforms allowing for affordable sequencing of an entire human genome. This process incorporates a two-phase approach that will attempt to reduce sequencing costs from $10 million using Sanger sequencing with capillary array electrophoresis (CAE) to about $1,000, while also linking the costs to a measurable standard of quality. Approaches to achieving these gaols, such as providing grants to research sequencing by ligation and nanopore approaches, are discussed.

The article presents a summary of the workshop "Emerging Techniques in Glycobiology," organized by R. Reid Townsend of the University of California at San Francisco in the United States. Key issues discussed include the microanalysis of oligosaccharides that are attached to glycoproteins, the capillary electrophoresis of fluorescent carbohydrate derivatives and approaches to automating the enzymatic structural analysis of glycoprotein-derived glycans and chemical release. The references and equipment used for the workshop are also cited.

Presents a calendar events regarding biology in the U.S. from March 18, 1991 to June 1, 1991. Course on applications of sensory evaluation in product development; International meeting of the electrophoresis societies; Symposium on manipulation of the avian genome; North American Wildlife and Natural Resources Conference; Symposium on cytokines and their receptors and wound repair.

The article presents a summary of the workshop "High-Performance Electrophoresis," organized by Lloyd M. Smith of the University of Wisconsin in the United States. Key issues discussed include the performance of capillary array electrophoresis through the use of laser-excited confocal fluorescence detection, high-speed DNA sequencing in ultrathin gels and the use of capillary electrophoresis in the analysis of recombinant proteins. The references and equipment used for the workshop are also cited.