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1.
Animal ; 16(7): 100544, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35777298

RESUMEN

Resilience can be defined as the ability of an animal to remain productive in the face of diverse environmental challenges. Several factors contribute to an animal's resilience including its ability to resist disease, cope with climatic extremes and respond to stressors. Immune competence, a proxy trait for general disease resistance, is expected to contribute to an animal's resilience. This research aimed to develop a practical method to assess immune competence in Merino sheep which would not restrict the future sale of tested animals, and to estimate genetic parameters associated with the novel trait. We also aimed to explore associations between immune competence and other industry-relevant disease resistance and fitness-related traits and to assess the ability of immune competence phenotypes to predict health outcomes. Here, the ability of Merino wethers (n = 1 339) to mount both an antibody-mediated and cell-mediated immune response was used to define their immune competence phenotype. For that purpose, antigens in a commercial vaccine were administered at the commencement of weaning and their responses were assessed. Univariate sire models were used to estimate variance components and heritabilities for immune competence and its component traits. Bivariate sire models were used to estimate genetic correlations between immune competence and a range of disease resistance and fitness-related traits. The heritability of immune competence and its component traits, antibody-mediated immune response and cell-mediated immune response were estimated at 0.49 ±â€¯0.14, 0.52 ±â€¯0.14 and 0.36 ±â€¯0.11, respectively. Immune competence was favourably genetically correlated with breech flystrike incidence (-0.44 ±â€¯0.39), worm egg count (-0.19 ±â€¯0.23), dag score (-0.26 ±â€¯0.31) and fitness compromise (-0.35 ±â€¯0.24) but not fleece rot (0.17 ±â€¯0.23). Results suggest that selection for immune competence has the potential to improve the resilience of Merino sheep; however, due to the large standard errors associated with correlation estimates reported here, further studies will be required in larger populations to validate associations between immune competence and disease resistance and fitness traits in Australian Merino sheep.


Asunto(s)
Resistencia a la Enfermedad , Animales , Australia , Fenotipo , Destete
2.
Pneumologie ; 73(9): 538-543, 2019 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-31533175

RESUMEN

A 47-year-old man presented with fever, weight loss and pulmonary consolidations and cavitation in the x-ray of the thorax. The comprehensive diagnostics resulted pulmonary epitholoid cell granulomas, therefore an immunosuppressive therapy was applied on suspicion of sarcoidosis. Progressivly the pulmonary infiltration increased and cerebral and abdominal abscesses were determined with microbiological detection of Nocardia farcinica. Despite antibiotic therapy, the patient died in a septic shock with multiple organ failure.Nocardiosis is a rare granulomatous bacterial infectious disease. Risk factors include immunosuppression and structural lung diseases. Characteristic is an abscess formation that can occur in any organ, while pulmonary onset is common.The case demonstrates the importance of considering rare differential diagnoses in the detection of pulmonary epithelioid granulomas.


Asunto(s)
Fiebre/etiología , Enfermedad Granulomatosa Crónica/microbiología , Pulmón/microbiología , Nocardiosis/microbiología , Diagnóstico Diferencial , Granuloma/patología , Humanos , Masculino , Persona de Mediana Edad , Nocardia , Nocardiosis/diagnóstico , Pérdida de Peso
3.
Res Vet Sci ; 122: 72-80, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30468879

RESUMEN

DTS: Diathermic Syncope® (DTS) is a novel system for rendering animals insensible prior to slaughter, utilizing microwave energy to induce a rise in temperature in the brain to a point at which the animal is expected to lose consciousness. During development and optimisation of the system, two trials were carried out utilizing non-anaesthetized adult cattle, to gather data on behavioural outcomes and EEG changes following energy application. In trial1, ten cattle received DTS treatments (high energy >290 kJ, n = 3; low energy <200 kJ, n = 4; and intermediate 200 < 290 kJ, n = 3), and seven received captive bolt stunning, prior to exsanguination. In trial 2, following improvements to the efficiency of energy delivery, 20 cattle received DTS (200-360 kJ). Post treatment EEG was characterized by seizure-like activity and reductions in 95% spectral edge and median frequencies; with EEG suppression persisting for at least 80 s up to over 4 min post treatment application. Animals showed: Loss of posture, Loss of corneal responses; Loss of withdrawal response (pinprick); Eye staring, not following movement. The animals remained unresponsive to stimuli for up to 4 min post DTS, and behavioural expression of distress was not observed. Seventeen of the 30 animals showed indications of returning reflex responses after 100 s post treatment, suggesting that animals receiving lower energy applications may recover from the stun.


Asunto(s)
Mataderos , Bienestar del Animal , Bovinos/fisiología , Microondas , Inconsciencia/veterinaria , Animales , Encéfalo/efectos de la radiación , Electroencefalografía/veterinaria , Reflejo
4.
J Anim Sci ; 88(6): 2144-52, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20154169

RESUMEN

To identify long-distance transport durations compatible with acceptable animal welfare, the aim of this study was to determine the responses of healthy sheep to road transport under good conditions for 12, 30, or 48 h. Merino ewes (n = 120; 46.9 +/- 0.39 kg) were allocated to road transport treatments of 12, 30, or 48 h, with 2 replicates per treatment. Blood and urine samples and BW were taken pretransport and at 0, 24, 48, and 72 h posttransport. Lying time was measured using data loggers. Increasing transport durations resulted in reduced (P < 0.001) BW and increased (P < 0.05) hemoconcentration, but these effects did not exceed clinically normal ranges for any transport duration, and sheep generally recovered to pretransport values within 72 h posttransport. Sheep transported for 30 and 48 h had less BW on arrival than sheep transported for 12 h (P < 0.001). There were no differences (P > 0.05) between the 12- and 30-h treatments in sheep BW at 24, 48, or 72 h after arrival. Sheep transported for 30 and 48 h had greater total plasma protein concentrations on arrival than sheep transported for 12 h (P < 0.001). Although the white cell count and neutrophil:lymphocyte ratio increased with transport, there were no consistent effects of transport duration. There were also no effects (P = 0.10) of transport duration on plasma cortisol concentrations. There were no treatment differences (P > 0.05) in lying times during the first 18 h after arrival. Sheep transported for 30 or 48 h lay down less (P < 0.05) than sheep transported for 12 h between 18 and 24 h after arrival, but there were no other differences over 72 h. These findings indicate that healthy adult sheep, transported under good conditions, can tolerate transport durations of up to 48 h without undue compromise to their welfare.


Asunto(s)
Bienestar del Animal , Conducta Animal/fisiología , Hidrocortisona/sangre , Ovinos/fisiología , Estrés Fisiológico/fisiología , Ácido 3-Hidroxibutírico/sangre , Animales , Recuento de Células Sanguíneas/veterinaria , Peso Corporal/fisiología , Creatina Quinasa/sangre , Femenino , Haptoglobinas/análisis , Hematócrito/veterinaria , Hemoglobinas/análisis , Masculino , Concentración Osmolar , Albúmina Sérica/análisis , Transportes
5.
Appl Environ Microbiol ; 73(22): 7465-70, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17890329

RESUMEN

Francisella tularensis subsp. holarctica is widely disseminated in North America and the boreal and temperate regions of the Eurasian continent. Comparative genomic analyses identified a 1.59-kb genomic deletion specific to F. tularensis subsp. holarctica isolates from Spain and France. Phylogenetic analysis of strains carrying this deletion by multiple-locus variable-number tandem repeat analysis showed that the strains comprise a highly related set of genotypes, implying that these strains were recently introduced or recently emerged by clonal expansion in France and the Iberian Peninsula.


Asunto(s)
Francisella tularensis/genética , Eliminación de Gen , Genoma Bacteriano , Análisis por Conglomerados , ADN Bacteriano/análisis , ADN Bacteriano/genética , Electroforesis en Gel de Agar , Francia , Francisella/genética , Francisella/aislamiento & purificación , Francisella tularensis/clasificación , Francisella tularensis/aislamiento & purificación , Genes Bacterianos/genética , Reacción en Cadena de la Polimerasa , España , Especificidad de la Especie
6.
Arch Virol ; 151(9): 1863-74, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16736092

RESUMEN

Currently circulating influenza B viruses can be divided into two antigenically and genetically distinct lineages referred to by their respective prototype strains, B/Yamagata/16/88 and B/Victoria/2/87, based on amino acid differences in the hemagglutinin surface glycoprotein. During May and July 2005, clinical specimens from two early season influenza B outbreaks in Arizona and southeastern Nepal were subjected to antigenic (hemagglutinin inhibition) and nucleotide sequence analysis of hemagglutinin (HA1), neuraminidase (NA), and NB genes. All isolates exhibited little reactivity with the B/Shanghai/361/2002 (B/Yamagata-like) vaccine strain and significantly reduced reactivity with the previous 2003/04 B/Hong Kong/330/2001 (B/Victoria-like) vaccine strain. The majority of isolates were antigenically similar to B/Hawaii/33/2004, a B/Victoria-like reference strain. Sequence analysis indicated that 33 of 34 isolates contained B/Victoria-like HA and B/Yamagata-like NA and NB proteins. Thus, these outbreak isolates are both antigenically and genetically distinct from the current Northern Hemisphere vaccine virus strain as well as the previous 2003-04 B/Hong Kong/330/2001 (B/Victoria lineage) vaccine virus strain but are genetically similar to B/Malaysia/2506/2004, the vaccine strain proposed for the coming seasons in the Northern and Southern Hemispheres. Since these influenza B outbreaks occurred in two very distant geographical locations, these viruses may continue to circulate during the 2006 season, underscoring the importance of rapid molecular monitoring of HA, NA and NB for drift and reassortment.


Asunto(s)
Virus de la Influenza B/genética , Virus de la Influenza B/aislamiento & purificación , Gripe Humana/epidemiología , Gripe Humana/virología , Análisis por Conglomerados , Reacciones Cruzadas , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Glicoproteínas Hemaglutininas del Virus de la Influenza/inmunología , Humanos , Virus de la Influenza B/inmunología , Datos de Secuencia Molecular , Nepal/epidemiología , Filogenia , Análisis de Secuencia de ADN , Estados Unidos/epidemiología , Proteínas Virales/genética , Proteínas Virales/inmunología
7.
J Clin Microbiol ; 39(10): 3446-51, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11574554

RESUMEN

Molecular surveillance of pathogens has shown the need for rapid and dependable methods for the identification of organisms of clinical and epidemiological importance. As the leading cause of community-acquired pneumonia, Streptococcus pneumoniae was used as a model organism to develop and refine a real-time fluorescence PCR assay and enhanced DNA purification method. Seventy clinical isolates of S. pneumoniae, verified by latex agglutination, were screened against 26 negative control clinical isolates employing a TaqMan assay on a thermocycler (LightCycler). The probe, constructed from the lytA gene, correctly detected all S. pneumoniae genomes without cross-reaction to negative controls. The speed and ease of this approach will make it adaptable to identification of many bacterial pathogens and provide potential for adaptation to direct detection from patient specimens.


Asunto(s)
Neumonía Neumocócica/diagnóstico , Neumonía Neumocócica/microbiología , Reacción en Cadena de la Polimerasa/métodos , Streptococcus pneumoniae/clasificación , Cartilla de ADN/genética , ADN Bacteriano/análisis , ADN Bacteriano/aislamiento & purificación , Fluorescencia , Humanos , N-Acetil Muramoil-L-Alanina Amidasa/genética , Sensibilidad y Especificidad , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/aislamiento & purificación , Polimerasa Taq/metabolismo
8.
J Bacteriol ; 183(17): 5163-70, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11489870

RESUMEN

It is thought that in the gram-negative soil bacterium Sinorhizobium meliloti the protein ExoP is involved in biosynthesis of the acidic exopolysaccharide succinoglycan (EPS I). The amounts and compositions of EPS I produced by mutants expressing ExoP proteins characterized by specific amino acid substitutions in the C-terminal cytoplasmic domain were analyzed. The cytoplasmic domain of the ExoP protein was shown to have ATPase activity. Mutations in the highly conserved Walker A ATP-binding motif prevented ATPase activity of the ExoP protein. Phenotypically, these mutations resulted in much lower levels of succinoglycan which consisted only of monomers of the octasaccharide repeating unit. The ExoP protein has similarities to proteins with autophosphorylating protein tyrosine kinase activity. We found that ExoP was phosphorylated on tyrosine and that site-directed mutagenesis of specific tyrosine residues in the cytoplasmic domain of ExoP resulted in an altered ratio of low-molecular-weight succinoglycan to high-molecular-weight succinoglycan.


Asunto(s)
Adenosina Trifosfatasas/metabolismo , Proteínas Bacterianas/metabolismo , Citoplasma/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de Transporte de Membrana , Polisacáridos Bacterianos/metabolismo , Sinorhizobium meliloti/metabolismo , Tirosina/metabolismo , Adenosina Trifosfato/metabolismo , Proteínas Bacterianas/genética , Sitios de Unión , Proteínas de la Membrana/genética , Peso Molecular , Mutagénesis Sitio-Dirigida , Mutación , Fenotipo , Fosforilación , Conformación Proteica , Sinorhizobium meliloti/genética , Tirosina/genética
9.
Appl Environ Microbiol ; 66(11): 4854-62, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11055935

RESUMEN

Antibiotic resistance plasmids were exogenously isolated in biparental matings with piggery manure bacteria as plasmid donors in Escherichia coli CV601 and Pseudomonas putida UWC1 recipients. Surprisingly, IncQ-like plasmids were detected by dot blot hybridization with an IncQ oriV probe in several P. putida UWC1 transconjugants. The capture of IncQ-like plasmids in biparental matings indicates not only their high prevalence in manure slurries but also the presence of efficiently mobilizing plasmids. In order to elucidate unusual hybridization data (weak or no hybridization with IncQ repB or IncQ oriT probes) four IncQ-like plasmids (pIE1107, pIE1115, pIE1120, and pIE1130), each representing a different EcoRV restriction pattern, were selected for a more thorough plasmid characterization after transfer into E. coli K-12 strain DH5alpha by transformation. The characterization of the IncQ-like plasmids revealed an astonishingly high diversity with regard to phenotypic and genotypic properties. Four different multiple antibiotic resistance patterns were found to be conferred by the IncQ-like plasmids. The plasmids could be mobilized by the RP4 derivative pTH10 into Acinetobacter sp., Ralstonia eutropha, Agrobacterium tumefaciens, and P. putida, but they showed diverse patterns of stability under nonselective growth conditions in different host backgrounds. Incompatibility testing and PCR analysis clearly revealed at least two different types of IncQ-like plasmids. PCR amplification of total DNA extracted directly from different manure samples and other environments indicated the prevalence of both types of IncQ plasmids in manure, sewage, and farm soil. These findings suggest that IncQ plasmids play an important role in disseminating antibiotic resistance genes.


Asunto(s)
Bacterias/genética , Farmacorresistencia Microbiana/genética , Variación Genética , Estiércol/microbiología , Plásmidos/genética , Animales , Bacterias/efectos de los fármacos , Conjugación Genética , Escherichia coli/genética , Hibridación de Ácido Nucleico/métodos , Reacción en Cadena de la Polimerasa/métodos , Pseudomonas putida/genética , Porcinos , Transformación Genética
10.
J Clin Microbiol ; 38(9): 3407-12, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10970392

RESUMEN

Methicillin-resistant staphylococci (MRS) are one of the most common causes of nosocomial infections and bacteremia. Standard bacterial identification and susceptibility testing frequently require as long as 72 h to report results, and there may be difficulty in rapidly and accurately identifying methicillin resistance. The use of the PCR is a rapid and simple process for the amplification of target DNA sequences, which can be used to identify and test bacteria for antimicrobial resistance. However, many sample preparation methods are unsuitable for PCR utilization in the clinical laboratory because they either are not cost-effective, take too long to perform, or do not provide a satisfactory DNA template for PCR. Our goal was to provide same-day results to facilitate rapid diagnosis and therapy. In this report, we describe a rapid method for extraction of bacterial DNA directly from blood culture bottles that gave quality DNA for PCR in as little as 20 min. We compared this extraction method to the standard QIAGEN method for turnaround time (TAT), cost, purity, and use of template in PCR. Specific identification of MRS was determined using intragenic primer sets for bacterial and Staphylococcus 16S rRNA and mecA gene sequences. The PCR primer sets were validated with 416 isolates of staphylococci, including methicillin-resistant Staphylococcus aureus (n = 106), methicillin-sensitive S. aureus (n = 134), and coagulase-negative Staphylococcus (n = 176). The total supply cost of our extraction method and PCR was $2.15 per sample with a result TAT of less than 4 h. The methods described herein represent a rapid and accurate DNA extraction and PCR-based identification system, which makes the system an ideal candidate for use under austere field conditions and one that may have utility in the clinical laboratory.


Asunto(s)
Sangre/microbiología , ADN Bacteriano/aislamiento & purificación , Resistencia a la Meticilina/genética , Reacción en Cadena de la Polimerasa/métodos , Infecciones Estafilocócicas/microbiología , Staphylococcus/clasificación , Técnicas de Tipificación Bacteriana , Coagulasa/metabolismo , ADN Bacteriano/análisis , Genes Bacterianos , Genes de ARNr , Humanos , Meticilina/farmacología , Pruebas de Sensibilidad Microbiana , Reacción en Cadena de la Polimerasa/economía , ARN Ribosómico 16S/genética , Infecciones Estafilocócicas/sangre , Infecciones Estafilocócicas/diagnóstico , Staphylococcus/efectos de los fármacos , Staphylococcus/genética , Staphylococcus/aislamiento & purificación , Factores de Tiempo
11.
Mil Med ; 165(11): 816-20, 2000 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11143425

RESUMEN

At present, the use of molecular probes and polymerase chain reaction (PCR) for the identification of microorganisms in body fluids or tissues is becoming more commonplace. There is an added advantage when serological or culture methods are difficult, expensive, or unavailable. Slow-growing or fastidious microorganisms, including Mycobacterium tuberculosis, spirochetes, viruses, and the dimorphic fungi, can be detected rapidly using these techniques. The presence of different chromosomal or plasmid-mediated antibiotic-resistant markers can also be determined. PCR is an extremely powerful tool that has been applied to research, and more recently it has been used to augment standard clinical applications. It is a very simple process that can amplify nucleic acid sequences, both DNA and RNA, a million times over. The sensitivity, rapidity, broad applicability, and compactness of this technology make it an ideal candidate for use in the military arena. We recently established a molecular biology laboratory at a Deployable Medical System at the Camp Parks Army Reserve Training Facility in Dublin, California. This article will briefly summarize the use of PCR and its applicability in the air-transportable hospital field environment. Proper handling, processing, and testing as well as the requirements for setting up a molecular biology laboratory will be discussed. Finally, the benefits and disadvantages of using PCR-based techniques in the deployed field environment will be considered.


Asunto(s)
Medicina Aeroespacial , ADN Bacteriano/sangre , Hospitales Militares , Unidades Móviles de Salud , Reacción en Cadena de la Polimerasa/estadística & datos numéricos , Estudios de Factibilidad , Humanos , Laboratorios de Hospital , Estados Unidos
12.
Plasmid ; 42(1): 42-4, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10413664

RESUMEN

We have cloned and identified an insertion sequence, IS1485, that was present in several members of the genus Enterococcus. IS1485 exists in varying copy numbers with at least 12 copies in E. durans (ATCC 11576), 3 copies in E. faecium (ATCC 19434), and one copy each in E. faecalis (ATCC 19433) and E. avium (ATCC 14024). It was also detected in clinical strains of E. gallinarum, E. casseliflavus, and E. saccharolyticus. IS1485 is 1366 bp in length, it has imperfect terminal inverted repeats with 25 of the terminal 39 residues matched, and it contains three open reading frames exceeding 50 codons, designated orfA, orfB, and orfC. The largest, orfB, was located 36 bp downstream and in the -1 reading frame relative to orfA; orfC is oriented in the opposite direction and overlaps orfA. The genetic organization of IS1485 resembles that of members of the IS3 family of transposable elements. Sequence homology exists with several members of the IS3 family especially with IS199 from Streptococcus mutans.


Asunto(s)
Elementos Transponibles de ADN/genética , Enterococcus/genética , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , ADN Bacteriano/genética , Enterococcus/aislamiento & purificación , Humanos , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Especificidad de la Especie , Streptococcus mutans/genética
13.
Mil Med ; 163(4): 226-8, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9575767

RESUMEN

Polymerase chain reaction (PCR) is a multi-faceted technology that is advancing disease detection. For pathology and clinical laboratories, PCR will be the tool of choice into the next century as scientists continue to develop and refine new uses. An amazingly simple process that amplifies nucleic acid sequences, PCR will change the practice of medicine because it will play a role in all aspects of the patient care continuum from diagnosis to treatment monitoring. Some striking applications range from detecting infectious and inherited diseases to assessing pharmacologic interventions. Additionally, the remarkable sensitivity of PCR will allow determination of a patient's genetic predisposition to diseases, thereby improving prevention modalities. Thus, medical practitioners should gain a basic understanding of this phenomenal cornerstone of molecular diagnostics. This article briefly reviews the history, theory, and uses of PCR and discusses relevant applications for military medicine.


Asunto(s)
Reacción en Cadena de la Polimerasa , Humanos , Medicina Militar
14.
J Bacteriol ; 178(18): 5464-71, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8808937

RESUMEN

The gene required for methicillin resistance in staphylococci, mecA, encodes the low-affinity penicillin-binding protein 2a (PBP2a). Transcriptional regulation of mecA is accomplished in some isolates by mecR1 and mecI, cotranscribed chromosomal genes that encode a putative signal transducer and a transcriptional repressor, respectively. Two Staphylococcus aureus strains that have identical mecR1-mecI nucleotide sequences, BMS1 and N315P, both exhibit low-level, heterotypic expression of methicillin resistance and contain no beta-lactamase coregulatory sequences. mecR1-mecI was amplified from BMS1 by PCR and was shown to be functional on a high-copy-number plasmid when introduced into an S. aureus strain with a deleted mecR1-mecI locus. Cloned mecR1-mecI repressed phenotypic expression of methicillin resistance, mecA transcription and PBP2a production and mediated PBP2a induction in response to certain beta-lactam antibiotics. However, mecR1-mecI had different regulatory activities in its native chromosomal location in N315P compared with those in BMS1. Uninduced mecA transcription was markedly repressed in N315P, and mecI inactivation increased mecA transcription and PBP2a production 5- and 40-fold, respectively. Furthermore, the N315P phenotype changed from low-level, heterotypic resistance with intact mecI to high-level, homotypic resistance in strains with disrupted mecI. In contrast, uninduced BMS1 produced abundant mecA transcript and PBP2a, while the disruption of mecI had no effect on phenotype and little effect on mecA transcription or PBP2a production. Thus, mecI-mediated repression of mecA appears to be dysfunctional in BMS1 because of the presence or absence of additional regulatory cofactors. Furthermore, heterotypic resistance expression in this strain is independent of mecA transcriptional regulation.


Asunto(s)
Proteínas Portadoras/metabolismo , Regulación Bacteriana de la Expresión Génica , Hexosiltransferasas , Resistencia a la Meticilina/genética , Muramoilpentapéptido Carboxipeptidasa/metabolismo , Peptidil Transferasas , Staphylococcus aureus/genética , Transcripción Genética , Proteínas Bacterianas/genética , Clonación Molecular , Mutagénesis , Proteínas de Unión a las Penicilinas , Reacción en Cadena de la Polimerasa , ARN Bacteriano/análisis , ARN Mensajero/análisis , Secuencias Reguladoras de Ácidos Nucleicos , Proteínas Represoras/genética , Especificidad de la Especie
15.
Antimicrob Agents Chemother ; 40(4): 924-9, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8849253

RESUMEN

We have previously shown (G. L. Archer, D. M. Niemeyer, J. A. Thanassi, and M. J. Pucci, Antimicrob. Agents Chemother. 38:447-454, 1994) that some methicillin-resistant staphylococcal isolates contain a partial deletion of the genes (mecR1 and mecI) that regulate the transcription of the methicillin resistance structural gene (mecA). When a fragment of DNA inserted at the point of the mecR1 deletion was used as a probe, hybridization with multiple bands was detected for Staphylococcus haemolyticus genomic DNA. In the present study, DNA sequencing of four unique clones recovered from a lambda library of S. haemolyticus revealed identical 1,934-bp elements. Each element, designated IS1272, contained 16-bp terminal inverted repeats (sequence identity, 15 of 16 bp) and two open reading frames of 819 and 687 bp; there were no flanking target site duplications. Database searches yielded amino acid homology with proteins predicted to be encoded by open reading frames from a putative insertion sequence element from Enterococcus hirae. DNA probes from each end and the middle of IS1272 were hybridized with restriction endonuclease-digested genomic DNA from clinical S. haemolyticus, Staphylococcus epidermidis, and Staphylococcus aureus isolates. Each of the 20 or more copies of the element found in S. haemolyticus isolates was intact, and copies were found in most chromosomal SmaI fragments. S. aureus and S. epidermidis isolates contained mostly incomplete fragments of the element, and there were many more hybridizing fragments in methicillin-resistant than in methicillin-susceptible isolates. IS1272, which appears to be primarily resident in S. haemolyticus, has disseminated to multiple staphylococcal species and is prevalent in multiresistant isolates.


Asunto(s)
Elementos Transponibles de ADN/genética , Staphylococcus/genética , Secuencia de Aminoácidos , Secuencia de Bases , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico
16.
Artículo en Inglés | MEDLINE | ID: mdl-8563403

RESUMEN

The physicians of the Children's Asthma Center and the computer scientists of Information Services at Texas Children's Hospital set out to design a system that is comfortable to use, structured enough to effectively measure outcomes, yet flexible enough to conserve the individuality of the patient. To achieve these goals, we examined how the differential diagnosis process is applied to clinical decision making and implemented it in a clinical workstation. Unique patterns representing the state of the patient's disease are formed by dynamically selecting pertinent sets of observations, assigning attributes to these observations, and describing relationships between observations and/or sets of observations.


Asunto(s)
Sistemas de Registros Médicos Computarizados , Sistemas en Línea , Asma , Sistemas de Información en Hospital , Humanos , Registros de Enfermería , Proyectos Piloto , Sistemas de Atención de Punto , Texas , Interfaz Usuario-Computador
17.
Mil Med ; 159(12): 732-5, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7723996

RESUMEN

Infections caused by drug-resistant microorganisms have posed a medical challenge since the advent of antimicrobial therapy. With the emergence of resistant strains, new antibiotics were available and introduced with great success until this decade. The appearance of multiresistant microorganisms pose a real and immediate public health concern. Are we entering into the post-antibiotic era? Will we return to pre-antimicrobial-era conditions, with morbidity and mortality resulting from untreatable infectious complications? The race to stay ahead of multiresistance involves not only continued drug development and selective use but elucidation of bacterial regulation of resistance. One way to ensure continued success of antimicrobial therapy is the identification of new bacterial targets--genes and their products involved in regulating or mediating resistance. Discussion will focus on one well-defined resistance mechanism in Gram-negative bacteria, the chromosomally located amp operon, responsible for one mechanism of beta-lactam resistance.


Asunto(s)
Antibacterianos/farmacología , Regulación Enzimológica de la Expresión Génica , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/enzimología , Resistencia betalactámica/genética , beta-Lactamasas/genética , Carbapenémicos/farmacología , Cefalosporinas/farmacología , Resistencia a Múltiples Medicamentos/genética , Monobactamas/farmacología , Penicilinas/farmacología , beta-Lactamasas/biosíntesis
18.
Trends Microbiol ; 2(10): 343-7, 1994 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7850198

RESUMEN

The gene mediating resistance to methicillin in staphylococci (mecA) and its flanking sequences (mec DNA) make up a chromosomal DNA locus that is unique to methicillin-resistant bacteria; no equivalent locus exists in methicillin-susceptible cells. The origin of mec DNA is not known, but evidence supports horizontal transfer of mec DNA between different staphylococcal species and of the mecA gene between different Gram-positive genera.


Asunto(s)
ADN Bacteriano/genética , Resistencia a la Meticilina/genética , Staphylococcus/genética , Mapeo Cromosómico , Clonación Molecular , Eliminación de Gen , Genes Bacterianos/genética , Homología de Secuencia de Aminoácido
19.
Antimicrob Agents Chemother ; 38(3): 447-54, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7911288

RESUMEN

DNA probes consisting of pUC19 containing cloned Staphylococcus aureus chromosomal fragments were constructed from two methicillin-resistant S. aureus strains with different DNA sequences 5' to mecA, the gene that mediates methicillin resistance. The probe from one strain, BMS1, contained a portion of the regulatory sequences (the terminal 641 bp of mecR1 and all of mecI) associated with the induction and repression of mecA transcription (pGO195). The second probe, from strain COL (pGO198), contained DNA not found in strain BMS1. This DNA was within the sequences added at the site of a mecR1 deletion. Genomic digests of 14 S. aureus isolates recovered between 1961 and 1969 all hybridized with pGO198. In contrast, 78% (36 of 46) of the S. aureus organisms isolated since 1988 hybridized with pGO195 but not with pGO198; the remainder hybridized with pGO198. No S. aureus isolates hybridized with both probes. Staphylococcus epidermidis digests hybridized with pGO198 (46%), pGO195 (14%), or both probes (35%); all 20 Staphylococcus haemolyticus isolates hybridized with pGO198. The restriction fragment length polymorphism patterns of all pGO198-hybridizing regions in S. aureus were identical to those in strain COL. In addition, the mecR1 deletion junction nucleotide sequences of eight S. aureus and six S. epidermidis isolates were identical. However, 21 of 23 S. epidermidis and all 20 S. haemolyticus isolates had from 5 to more than 20 additional chromosomal bands that hybridized with pGO198; none of 21 S. aureus isolates had additional hybridizing bands. These data suggest that the additional DNA responsible for the mecR1 deletion was part of a repetitive, and possibly mobile, element resident in coagulase-negative staphylococci but not in S. aureus. These data also support a hypothesis that the deletion event occurred in a coagulase-negative staphylococcus with subsequent acquisition of the interrupted sequences by S. aureus.


Asunto(s)
ADN Bacteriano/genética , Resistencia a la Meticilina/genética , Staphylococcus/genética , Secuencia de Bases , Clonación Molecular , Sondas de ADN , Elementos Transponibles de ADN , ADN Bacteriano/análisis , Humanos , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Fenotipo , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Infecciones Estafilocócicas/microbiología , Staphylococcus/química , Staphylococcus aureus/química , Staphylococcus aureus/genética , Staphylococcus epidermidis/química , Staphylococcus epidermidis/genética
20.
JAMA ; 264(12): 1570-4, 1990 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-2395199

RESUMEN

Cigarette smoking continues to be the leading preventable cause of death in California and the United States. Although substantial progress has been made over the past 25 years, there is growing recognition of the need for large-scale efforts to reduce tobacco use. Given their central roles in implementing public health programs and their ability to reach many of the groups most at risk of tobacco use uptake and tobacco-related disease, state health agencies have an important challenge before them. This article describes the development and operation of a statewide, publicly funded anti-tobacco use campaign currently undertaken by the California Department of Health Services under the auspices of the state's Tobacco Tax and Health Promotion Act of 1988 (Proposition 99), which increased excise taxes on cigarettes by 25 cents per pack sold in the state. A discussion of problems in implementation and operation being incurred may be relevant to the planning of similar campaigns elsewhere.


Asunto(s)
Promoción de la Salud/organización & administración , Prevención del Hábito de Fumar , Adolescente , Adulto , Publicidad , California , Femenino , Educación en Salud/economía , Promoción de la Salud/economía , Promoción de la Salud/legislación & jurisprudencia , Necesidades y Demandas de Servicios de Salud/economía , Humanos , Masculino , Persona de Mediana Edad , Plantas Tóxicas , Fumar/economía , Impuestos , Tabaco sin Humo
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