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1.
Eur J Cancer Care (Engl) ; 27(4): e12852, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29667288

RESUMEN

Treatment of cancer-related symptoms represents a major challenge for physicians. The purpose of this pilot study was to determine whether a brief bedside visual art intervention (BVAI) facilitated by art educators improves mood, reduces pain and anxiety in patients with haematological malignancies. Thirty-one patients (21 women and 10 men) were invited to participate in a BVAI where the goal of the session was to teach art technique for ~30 min. Primary outcome measures included the change in visual analog scale, the State-Trait Anxiety Inventory and the Positive and Negative Affect Schedule scale, from baseline prior to and immediately post-BVAI. Total of 21 patients (19 women and two men) participated. A significant improvement in positive mood and pain scores (p = .003 and p = .017 respectively) as well as a decrease in negative mood and anxiety (p = .016 and p = .001 respectively) was observed. Patients perceived BVAI as overall positive (95%) and wished to participate in future art-based interventions (85%). This accessible experience, provided by artists within the community, may be considered as an adjunct to conventional treatments in patients with cancer-related mood symptoms and pain, and future studies with balanced gender participation may support the generalisability of these findings.


Asunto(s)
Afecto , Ansiedad/terapia , Arteterapia/métodos , Dolor en Cáncer/terapia , Neoplasias Hematológicas/terapia , Adulto , Anciano , Ansiedad/psicología , Dolor en Cáncer/psicología , Femenino , Neoplasias Hematológicas/psicología , Humanos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Proyectos Piloto , Adulto Joven
2.
J Periodontal Res ; 52(6): 1032-1041, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28643938

RESUMEN

BACKGROUND AND OBJECTIVES: Epidemiological studies suggest a close association between periodontitis and prediabetes/insulin resistance (IR) but whether periodontitis causes prediabetes in humans is not known. Using various animal models, we have recently established that periodontitis can be an initiator of prediabetes, which is characterized by glucose intolerance, hyperinsulinemia and IR. In addition, our in vitro studies indicated that Porphyromonas gingivalis (Pg) induced insulin secretion in MIN6 ß cells and this induction was in part SerpinE1 (plasminogen activator inhibitor 1, PAI1) dependent. However, the mechanism(s) by which periodontitis induces prediabetes is not known. As α and ß cells in pancreatic islets are the major modulators of glucose levels, we investigated whether experimental periodontitis by oral application of a periodontal pathogen caused molecular and/or cellular alterations in pancreatic islets and whether SerpinE1 was involved in this process. MATERIAL AND METHODS: We induced periodontitis in C57BL/6 mice by oral application of a periodontal pathogen, Pg, and determined changes that occurred in islets following 22 weeks of Pg application. Pancreatic islet architecture was determined by 2-D and 3-D immunofluorescence microscopy and SerpinE1 and its target, urokinase plasminogen activator (uPA), as well as insulin, glucagon and Pg/gingipain in islets were detected by immunofluorescence. The presence of apoptotic islet cells was determined by both histochemical and immunofluorescence TUNEL assays. To investigate further the direct effect of Pg on apoptosis and the involvement of SerpinE1 in this process, we used SerpinE1 knockdown and scrambled control clones of the MIN6 pancreatic ß-cell line. RESULTS: Pg/gingipain was detected in both the periodontium and pancreas in the experimental group. Islets from animals that were administered Pg orally (experimental group) developed significant changes in islet architecture, upregulation of SerpinE1, and increased ß-cell apoptosis compared with the control group. We also observed that exposure of MIN6 cells to Pg in vitro resulted in apoptosis. However, apoptosis was significantly reduced when SerpinE1 expression by MIN6 cells was knocked down. CONCLUSION: Oral application of the periodontal pathogen Pg to C57BL/6 mice induces periodontitis, translocation of Pg/gingipain to the pancreas and results in complex alterations in pancreatic islet morphology. SerpinE1 appears to be involved in this process.


Asunto(s)
Islotes Pancreáticos/patología , Periodontitis/complicaciones , Inhibidor 1 de Activador Plasminogénico/metabolismo , Porphyromonas gingivalis/metabolismo , Estado Prediabético/etiología , Animales , Apoptosis , Infecciones por Bacteroidaceae/complicaciones , Western Blotting , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente
3.
Science ; 364(6441)2019 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-31097641

RESUMEN

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU69, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU69 is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU69's origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.

4.
Lab Anim ; 40(2): 144-52, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16600074

RESUMEN

Parvoviruses remain one of the most common viral infections seen in laboratory mouse colonies. The purpose of this study was to develop an antemortem polymerase chain reaction (PCR) assay to detect mice infected with mouse parvovirus-1 (MPV) and mice minute virus (MMV) using faecal samples. The MMV PCR assay consistently detected as few as 100 plasmid copies of MMV in faecal samples, while the MPV PCR assay detected as few as 10 plasmid copies of MPV. Faecal pellets from infected mice held at room temperature from 1 to 7 days tested positive by MMV and MPV PCR, respectively. This demonstrates that parvovirus DNA is stable in faecal samples kept at room temperature. PCR assays were also used to follow the length of MMV and MPV shedding in faeces from SENCAR mice, which were endemically infected with multiple agents. MMV faecal shedding was detected in 60-70% of the mice 5-7 weeks old, and by 13 weeks of age, faecal samples from all mice were negative for MMV. MPV faecal shedding was detected in 90-100% of the mice 5-11 weeks old; however, by 19 weeks of age, faecal samples from all mice were negative for MPV. These findings confirm that faecal shedding occurs for a limited time and suggest that 5-9-week-old mice are the most appropriate age group in endemically infected mice for faecal testing by MMV and MPV PCR.


Asunto(s)
Virus Diminuto del Ratón/aislamiento & purificación , Infecciones por Parvoviridae/virología , Parvovirus/aislamiento & purificación , Enfermedades de los Roedores/virología , Animales , Anticuerpos Antivirales/sangre , ADN Viral/química , ADN Viral/genética , Electroforesis en Gel de Agar/veterinaria , Ensayo de Inmunoadsorción Enzimática/veterinaria , Heces/virología , Ratones , Ratones Endogámicos SENCAR , Virus Diminuto del Ratón/genética , Infecciones por Parvoviridae/sangre , Parvovirus/genética , Reacción en Cadena de la Polimerasa/veterinaria , Enfermedades de los Roedores/diagnóstico
5.
Lab Anim ; 40(1): 63-9, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16460590

RESUMEN

Two newly recognized parvovirus species, rat parvovirus 1 (RPV-1) and rat minute virus 1 (RMV-1), were recently identified in naturally infected rats. In this study, two polymerase chain reaction (PCR) assays were developed to specifically detect RPV-1 and RMV-1. The RPV-1 PCR assay amplified the expected 487-bp deoxyribonucleic acid (DNA) fragment only in the presence of RPV-1 DNA; the RMV-1 PCR assay amplified the expected 843-bp product only from RMV-1 DNA, not from other rodent parvoviruses. The RPV-1 and the RMV-1 PCR assays detected approximately 18 and 70 copies of DNA template, respectively. These two PCR assays were shown to be sensitive, specific and rapid methods for detecting RPV-1 and RMV-1 infections in rats. These assays may also be valuable for evaluation of biological specimens for parvovirus contamination.


Asunto(s)
Infecciones por Parvoviridae/veterinaria , Parvovirus/aislamiento & purificación , Reacción en Cadena de la Polimerasa/veterinaria , Enfermedades de los Roedores/diagnóstico , Animales , Animales Recién Nacidos , Bioensayo , Cricetinae , Cartilla de ADN/química , ADN Viral/análisis , Humanos , Ratones , Virus Diminuto del Ratón/genética , Virus Diminuto del Ratón/aislamiento & purificación , Infecciones por Parvoviridae/diagnóstico , Infecciones por Parvoviridae/virología , Parvovirus/genética , Reacción en Cadena de la Polimerasa/métodos , Ratas , Enfermedades de los Roedores/virología , Análisis de Secuencia de ADN
6.
J Ethnopharmacol ; 96(1-2): 19-29, 2005 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-15588646

RESUMEN

Cordyceps sinensis is a medicinal fungus of Traditional Chinese Medicine. While there are a wide range of reported uses of Cordyceps sinensis in the literature, the reports that extracts of this fungus may alter apoptotic homeostasis are most intriguing. However, there are significant challenges regarding research surrounding Cordyceps sinensis, such as the difficulty identifying the various species of Cordyceps and the many conflicting reports of pharmacological function in the literature. In this review we outline what is known about the ability of Cordyceps sinensis to alter apoptotic homeostasis, attempt to reconcile the differences in reported function, identify the challenges surrounding future Cordyceps sinensis research, and delineate options for overcoming these critical hurdles.


Asunto(s)
Apoptosis , Cordyceps , Medicina Tradicional China , Apoptosis/efectos de los fármacos , Productos Biológicos/uso terapéutico , Humanos
7.
J Ethnopharmacol ; 96(1-2): 57-70, 2005 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-15588651

RESUMEN

Collaborating with traditional healers remains a valid method for the identification of potential lead compounds for novel pharmaceuticals. However, the knowledge of these traditional healers is rapidly being lost. Historic herbal texts provide a unique window to identify plants whose specific uses are no longer known. We have identified nine plants in the 17th century Ambonese Herbal: Volume I which were documented as having medicinal properties but which have not been examined in the current literature. We demonstrate that by evaluating plant and herb efficacy reports from historic texts, in the context of comprehensive modern databases such as NAPRALERT, we can ultimately identify candidate specimens deserving further pharmacological study.


Asunto(s)
Medicina de Hierbas , Medicina Tradicional , Extractos Vegetales/farmacología , Plantas Medicinales , Etnobotánica/historia , Medicina de Hierbas/historia , Historia del Siglo XVII , Historia del Siglo XVIII , Humanos , Manuscritos Médicos como Asunto , Medicina Tradicional/historia , Fitoterapia/historia , Extractos Vegetales/historia
8.
Mayo Clin Proc ; 75(8): 835-41, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10943239

RESUMEN

The use of herbal medicine in the United States has been increasing at a steady pace over the past decade. Most recent estimates suggest that the US population spends $5 billion per year for herbal supplements alone. Herbal supplements are receiving increasing exposure through national media, in lay journals, and more recently in the scientific press. Interest in herbal medicine has been facilitated by multiple factors, including the perception that pharmaceutical medications are expensive, overprescribed, and often dangerous. Alternatively, herbal medicine is often perceived as being "natural" and is therefore considered safe. While the growth of the herbal medicine industry in the United States can probably not continue at this accelerated pace indefinitely, there is little indication of any major slowing. Therefore, patients will continue to use herbal medications. Knowledge of these preparations (including their potential benefits and risks as well as their ability to interact with pharmaceutical medications) will enable physicians to provide a balanced and objective view to patients seeking information on herbal therapy.


Asunto(s)
Educación del Paciente como Asunto , Fitoterapia , Plantas Medicinales , Consejo , Aprobación de Drogas , Europa (Continente) , Conocimientos, Actitudes y Práctica en Salud , Humanos , Jurisprudencia , Pacientes , Estados Unidos
9.
Chest ; 111(2): 303-10, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9041973

RESUMEN

STUDY OBJECTIVE: To estimate the incidence of asthma in an elderly population and to describe the clinical characteristics, use of health services, and long-term survival of persons with onset of asthma after age 65 years. DESIGN: Retrospective cohort study. SETTING: Rochester, Minn. PATIENTS: All Rochester, Minn, residents age 65 years or older who met criteria for onset of definite or probable asthma from 1964 through 1983. INTERVENTIONS: None. MEASUREMENTS AND RESULTS: Ninety-eight Rochester residents (52 female, 46 male) with onset of asthma at or after age 65 years were identified. The age- and sex-adjusted incidence was 95/100,000 (95% confidence interval, 76 to 115/100,000). The age-specific incidence of asthma was 103/100,000 in residents aged 65 to 74 years, 81/100,000 in those aged 75 to 84 years, and 58/100,000 in residents older than 85 years. Only 11% had allergy skin tests, 24% had at least one office peak flow measurement, and 43% had at least one spirometry measurement. After the diagnosis of asthma, 40% had unscheduled ambulatory visits, 22% had emergency department visits, and 42% had at least one hospitalization for asthma. Observed survival was not significantly different from expected survival. CONCLUSIONS: Asthma is common in the elderly. Diagnostic evaluation was less intensive than present guidelines recommend. Following the diagnosis of asthma, a substantial proportion of these individuals required unscheduled ambulatory visits, emergency department visits, or hospitalizations. Asthma with onset after age 65 years was not associated with reduced survival.


Asunto(s)
Asma/epidemiología , Anciano , Anciano de 80 o más Años , Asma/diagnóstico , Asma/fisiopatología , Asma/terapia , Femenino , Humanos , Incidencia , Masculino , Minnesota/epidemiología , Pruebas de Función Respiratoria , Estudios Retrospectivos , Tasa de Supervivencia
10.
J Appl Physiol (1985) ; 71(6): 2346-51, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1723405

RESUMEN

Exercise is associated with release of catecholamines and vasoactive intestinal polypeptides. Recurrent exposure to catecholamines modifies the sensitivity of adrenoceptors. To test the hypothesis that exercise training may affect the sensitivity of the epicardial coronary arteries, we performed studies on isolated coronary arteries from male dogs capable of running on a treadmill. The animals were separated randomly into two groups: sedentary and exercise training. After 11 wk, rings of left circumflex and left anterior descending coronary arteries were studied in vitro. Contractions to alpha 1-adrenergic agonists (norepinephrine and phenylephrine) were not affected by exercise training. During contractions with prostaglandin F2 alpha, endothelium-dependent relaxations to alpha 2-adrenergic agonists (norepinephrine and UK 14304) were not reduced significantly by exercise training. The concentration-relaxation curves to beta-adrenergic agonists (norepinephrine, isoproterenol, and epinephrine) were shifted to the right after training. The concentration-response curves to vasoactive intestinal polypeptide, but not that to substance P, were shifted to the right in rings with endothelium from exercise-trained animals. These findings demonstrate a decrease in responsiveness of canine vascular smooth muscle to beta-adrenergic agonists and to vasoactive intestinal polypeptide after exercise training.


Asunto(s)
Vasos Coronarios/fisiología , Esfuerzo Físico/fisiología , Animales , Tartrato de Brimonidina , Vasos Coronarios/efectos de los fármacos , Perros , Técnicas In Vitro , Isoproterenol/farmacología , Masculino , Norepinefrina/farmacología , Fenilefrina/farmacología , Condicionamiento Físico Animal , Quinoxalinas/farmacología , Sustancia P/farmacología , Vasodilatación/efectos de los fármacos
11.
Med Sci Sports Exerc ; 21(5): 558-62, 1989 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2691817

RESUMEN

In dogs the concentrations of conjugated dopamine in plasma have previously been shown to increase after exercise training. This study was done to determine whether conjugated norepinephrine and epinephrine also increase. Fifteen dogs were randomly divided into training (N = 8) or sedentary (N = 7) groups. All dogs were exercised acutely for 5 min at 4 mph with a 12% grade, following a 3-min warm-up, before and after either a 12-wk training or a 12-wk sedentary period. Free and conjugated catecholamines were determined in blood drawn at rest and during acute exercise using high-performance liquid chromatography (HPLC) with electrochemical detection. Before training, free norepinephrine, epinephrine, dopamine, and conjugated norepinephrine increased in plasma during acute exercise. Following the 12-wk training period, there were significant increases in free and conjugated dopamine and in conjugated norepinephrine in plasma taken at rest. There were no such increases in resting catecholamines after a 12-wk sedentary period. After either training or sedentary periods, dogs responded to acute exercise with an increase in free norepinephrine and a decrease in conjugated norepinephrine. Thus, after training both conjugated norepinephrine and dopamine, but not conjugated epinephrine, increased in plasma. The data suggest that sulfation of catecholamines increases as a result of exercise training.


Asunto(s)
Dopamina/sangre , Epinefrina/sangre , Norepinefrina/sangre , Condicionamiento Físico Animal , Animales , Peso Corporal , Cromatografía Líquida de Alta Presión , Ensayos Clínicos como Asunto , Perros , Frecuencia Cardíaca , Masculino , Resistencia Física
12.
Med Sci Sports Exerc ; 21(4): 437-40, 1989 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-2674596

RESUMEN

Skeletal muscle biopsies from highly trained endurance athletes have been shown to contain an increased percentage of the creatine kinase MB (CK-MB) isoenzyme, which has been attributed to continuous regeneration of the skeletal muscle fibers in response to exercise-induced injury. The purpose of this study was to determine whether myocardium undergoes a similar degenerative-regenerative process as a result of exercise training. Fifteen mongrel dogs underwent a 12-wk period of training (N = 8) or cage confinement (N = 7). The animals were then sacrificed, and samples of left and right ventricular myocardium were analyzed for total CK activity and CK-MB isoenzyme content. Percentages of CK-MB were slightly but insignificantly higher from both ventricles of exercise-trained as compared with cage-confined dogs: left ventricle, 4.6 +/- 0.6% vs 3.3 +/- 0.6%, respectively (P = 0.15); right ventricle, 4.0 +/- 0.4% vs 3.0 +/- 0.8%, respectively (P = 0.29). We conclude that chronic exercise training does not induce physiologically important degenerative changes in myocardium.


Asunto(s)
Creatina Quinasa/metabolismo , Miocardio/enzimología , Condicionamiento Físico Animal , Animales , Perros , Isoenzimas
13.
J Ethnopharmacol ; 90(1): 57-62, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14698509

RESUMEN

Aqueous and alcohol extracts of Cordyceps sinensis (Berk) Succ. are used as a traditional medicine in China for the treatment of a wide range of diseases and are reported to have antioxidant and antiapoptotic properties. We therefore examined the ability of aqueous, organic, and alcohol extracts of Cordyceps sinensis to inhibit apoptosis induced either by hydrogen peroxide or Fas-receptor ligation; both stimuli induce apoptosis dependent on reactive oxygen species. Cells pre-incubated with Cordyceps sinensis extracts were equally sensitive to hydrogen peroxide and Fas-mediated apoptosis. Thus, the putative antioxidant and antiapoptotic properties of Cordyceps sinensis are insufficient to rescue cells from apoptosis induced by these stimuli in vitro.


Asunto(s)
Apoptosis/efectos de los fármacos , Cordyceps , Peróxido de Hidrógeno/farmacología , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Receptor fas/metabolismo , Frutas , Humanos , Células Jurkat , Medicina Tradicional China , Extractos Vegetales/farmacología
14.
Am J Occup Ther ; 31(7): 447-53, 1977 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-888906

RESUMEN

The Tactile Sensitivity Behavioral Responses Checklist was used to rate behavioral responses that demonstrate tactile defensiveness by children being administered the Southern California Kinesthesia and Tactile Perception Test battery. Hypothesizing that a group of five-year-old boys with hyperactive behaviors would have greater frequencies of tactile-sensitive behaviors than a group of nonhyperactive boys, and that tactile sensitivity would be negatively correlated with tactile discrimination, videotapes of 15 hyperactive and 25 nonhyperative boys being administered the test battery were rated on the checklist. Using the Mann-Whitney U test to compare each group for behavioral response, significant results at the .05 level were reached between groups for seven out of nine categories. A significant negative correlation between tactile sensitivity and tactile discrimination was reached for those children who completed the test battery. These findings support the research hypotheses and provide a more objective data base for recognizing and further researching tactile sensitivity.


Asunto(s)
Conducta Infantil , Hipercinesia , Tacto , Preescolar , Humanos , Masculino
15.
Am J Occup Ther ; 31(6): 357-61, 1977 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-879251

RESUMEN

Tactile defensiveness or sensitivity to being touched is a phenomenon observed by therapists during clinical testing and is reported based only on subjective data. The purpose of this study was to develop a more objective means of identifying this phenomenon. Videotaped observations of five-year-old boys being administered the Southern California Kinesthesia and Tactile Perception Test battery were used to identify behavioral reactions indicative of sensitivity to tactile stimulation. The population tested for a wide range of behaviors included hyperactive and normal five-year-old boys. These reactions were defined and categorized into a checklist of tactile-sensitive behaviroal responses. This checklist was then used on videotapes of 10 five-year-old boys by two raters to establish a measure of the reliability of this method of observing and recording behaviors. A reliability of .89 agreement with consensus was reached. These behavioral categories offer objective guides in identifying children with tactile defensiveness or sensitivity to tactile stimulation.


Asunto(s)
Conducta Infantil , Hipercinesia , Tacto , Preescolar , Humanos , Masculino , Pruebas Psicológicas , Grabación de Cinta de Video
19.
Clin Physiol Biochem ; 2(4): 137-45, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6237837

RESUMEN

The activities of phosphofructokinase, aldolase and pyruvate kinase were diminished in extracts from skeletal muscle of streptozotocin diabetic rats, whereas the activities of glucose phosphate isomerase and phosphoglucomutase were not changed. Treatment of diabetic rats with insulin restored the activity of phosphofructokinase to normal. A kinetic study of the partially purified enzyme from normal and diabetic rats showed identical Michaelis constants for ATP and equal sensitivity to inhibition by excess of this substrate. Extracts of quick frozen muscle from diabetic rats had higher levels of citrate (an inhibitor of phosphofructokinase) and lower levels of D-fructose-1,6-bisphosphate and D-glucose-1,6-bisphosphate (activators of this enzyme). The levels of D-fructose-6-phosphate, D-glucose-6-phosphate, ATP, ADP and AMP were the same for the two groups. Our data suggest that the in vivo decrease of phosphofructokinase activity in skeletal muscle of diabetic rats is due to a decrease in the level of the enzymatically active protein as well as to an unfavorable change in the level of several of its allosteric modulators.


Asunto(s)
Diabetes Mellitus Experimental/enzimología , Músculos/enzimología , Fosfofructoquinasa-1/deficiencia , Animales , Glucemia/metabolismo , Electroforesis en Gel de Poliacrilamida/métodos , Insulina/farmacología , Cinética , Músculos/metabolismo , Proteínas/metabolismo , Ratas , Ratas Endogámicas
20.
Infect Immun ; 67(2): 899-907, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9916106

RESUMEN

Haemophilus ducreyi lipooligosaccharide (LOS) is capable of inducing an inflammatory response in skin (A. A. Campagnari, L. M. Wild, G. Griffiths, R. J. Karalus, M. A. Wirth, and S. M. Spinola, Infect. Immun. 59:2601-2608, 1991) and likely contributes to the virulence of this sexually transmitted pathogen (B. A. Bauer, M. K. Stevens, and E. J. Hansen, Infect. Immun. 68:4290-4298, 1998). An open reading frame in H. ducreyi 35000 was found to encode a predicted protein that was 59% identical to the protein product of the rfaF (waaF) gene of Salmonella typhimurium. The H. ducreyi waaF gene was able to complement an S. typhimurium rfaF (waaF) mutant, a result which confirmed the identity of this gene. In contrast to the rfaF (waaF) gene of enteric bacteria, the H. ducreyi waaF gene was not located adjacent to other genes involved in lipopolysaccharide expression. Inactivation of the H. ducreyi waaF gene by insertion mutagenesis resulted in expression of a LOS that migrated much faster than wild-type LOS in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The LOS of this mutant also did not bind a monoclonal antibody directed against a cell surface-exposed epitope of wild-type H. ducreyi LOS. Testing of the wild-type H. ducreyi strain and its isogenic waaF mutant in the temperature-dependent rabbit model for dermal lesion production by H. ducreyi revealed that this waaF mutant was less virulent than the wild-type parent strain. Complementation of the H. ducreyi waaF mutant with the wild-type H. ducreyi waaF gene resulted in expression of both wild-type LOS and wild-type virulence by this mutant.


Asunto(s)
Glicosiltransferasas/genética , Haemophilus ducreyi/genética , Secuencia de Aminoácidos , Secuencia de Bases , ADN Bacteriano , Genes Bacterianos , Prueba de Complementación Genética , Haemophilus ducreyi/patogenicidad , Datos de Secuencia Molecular , Homología de Secuencia de Aminoácido , Virulencia
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