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2.
Hernia ; 19(3): 423-8, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25249251

RESUMEN

BACKGROUND: The aim of our study is to report our initial clinical experience with robotically assisted single-site transabdominal preperitoneal (RASS-TAPP) hernia repair, to verify the safety and efficacy of the procedure and to describe the surgical procedure. METHODS: We retrospectively reviewed all patients undergoing RASS-TAPP at our institution from March 2013 through December 2013. Data regarding patient demographics, type and location of hernia, operative time and clinical outcomes were collected and analyzed. RESULTS: Fourty five hernias were repaired in 34 patients (30M, 4F) by a single surgeon. The mean age was 49.3 years and mean BMI was 26.5. 31 lateral defects, 13 medial defects and 1 femoral defect were repaired. Three patients presented with recurrent hernias and nine had bilateral defects. The mean operative time for all cases was 80.5 min and for all unilateral hernias 69 min. Considering just the unilateral hernias without any additional procedures, operative time was 63 min. The mean follow-up time was 5.5 months. There has been one superficial surgical site infection, but no observed clinical recurrence or neuralgia to date. CONCLUSION: Robotically assisted single-site transabdominal preperitoneal hernia repair is safe and effective. The absence of clinical evidence of recurrence or neuralgia is encouraging and should promote further study.


Asunto(s)
Hernia Inguinal/cirugía , Herniorrafia/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Procedimientos Quirúrgicos Robotizados , Resultado del Tratamiento , Adulto Joven
4.
Vaccine ; 29(29-30): 4771-7, 2011 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-21570437

RESUMEN

Cynomolgus macaques, immunised at the 80 µg dose level with an rF1+rV vaccine (two doses, three weeks apart), were fully protected against pneumonic plague following inhalational exposure to a clinical isolate of Yersinia pestis (strain CO92) at week 8 of the schedule. At this time, all the immunised animals had developed specific IgG titres to rF1 and rV with geometric mean titres of 96.83±20.93 µg/ml and 78.59±12.07 µg/ml, respectively, for the 40 µg dose group; by comparison, the 80 µg dose group had developed titres of 114.4±22.1 and 90.8±15.8 µg/ml to rF1 and rV, respectively, by week 8. For all the immunised animals, sera drawn at week 8 competed with the neutralising and protective Mab7.3 for binding to rV antigen in a competitive ELISA, indicating that a functional antibody response to rV had been induced. All but one of the group immunised at the lower 40 µg dose-level were protected against infection; the single animal which succumbed had significantly reduced antibody responses to both the rF1 and rV antigens. Although a functional titre to rV antigen was detected for this animal, this was insufficient for protection, indicating that there may have been a deficiency in the functional titre to rF1 and underlining the need for immunity to both vaccine antigens to achieve protective efficacy against plague. This candidate vaccine, which has been evaluated as safe and immunogenic in clinical studies, has now been demonstrated to protect cynomolgus macaques, immunised in the clinical regimen, against pneumonic plague.


Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Vacuna contra la Peste/inmunología , Peste/prevención & control , Proteínas Citotóxicas Formadoras de Poros/inmunología , Animales , Anticuerpos Antibacterianos/sangre , Anticuerpos Neutralizantes/sangre , Antígenos Bacterianos/administración & dosificación , Antígenos Bacterianos/genética , Proteínas Bacterianas/administración & dosificación , Proteínas Bacterianas/genética , Modelos Animales de Enfermedad , Ensayo de Inmunoadsorción Enzimática , Inmunización Secundaria/métodos , Macaca fascicularis , Vacuna contra la Peste/administración & dosificación , Vacuna contra la Peste/genética , Proteínas Citotóxicas Formadoras de Poros/administración & dosificación , Proteínas Citotóxicas Formadoras de Poros/genética , Enfermedades de los Primates/prevención & control , Vacunación/métodos , Vacunas Sintéticas/administración & dosificación , Vacunas Sintéticas/genética , Vacunas Sintéticas/inmunología , Yersinia pestis/inmunología , Yersinia pestis/patogenicidad
6.
J Appl Microbiol ; 104(6): 1790-6, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18217940

RESUMEN

AIMS: To advance diagnostics and phylogenetics of Edwardsiella ictaluri by sequencing and characterizing its rrn operons. METHODS AND RESULTS: The Edw. ictaluri rrn operons were identified from a 5-7 kbp insert lambda library and from Edw. ictaluri fosmid clones. We present the complete sequences and analysis of all eight Edw. ictaluri rrn operons and unique regions located upstream and downstream. Two rrn operons were located in tandem with 169 bp separating them, which is apparently a conserved feature between Edw. ictaluri and Edwardsiella tarda. I-CeuI enzyme digestion of Edw. ictaluri genomic DNA and analysis by pulsed field gel electrophoresis indicated that rrn operon number and chromosomal locations are conserved within the species Edw. ictaluri. CONCLUSIONS: The rrn operons of Edw. ictaluri have similar structure and flanking regions compared with other members of the family Enterobacteriaceae; however, the presence of eight copies of the rrn operon makes Edw. ictaluri unique within the family. SIGNIFICANCE AND IMPACT OF THE STUDY: This research clarifies previous phylogenetic analyses of Edw. ictaluri and provides support for the Edw. ictaluri genome sequencing project. In addition, we identified a unique feature of two rrn operons that shows potential for the development of a diagnostic PCR method.


Asunto(s)
Edwardsiella ictaluri/genética , Explotaciones Pesqueras , Ictaluridae/microbiología , Microbiología Industrial , Operón de ARNr/genética , Animales , Secuencia de Bases , Cartilla de ADN/genética , Edwardsiella tarda/genética , Electroforesis en Gel de Campo Pulsado/métodos , Infecciones por Enterobacteriaceae/diagnóstico , Enfermedades de los Peces/diagnóstico , Enfermedades de los Peces/microbiología , Biblioteca Genómica , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa/métodos
7.
J Vet Pharmacol Ther ; 25(5): 363-9, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12423227

RESUMEN

Ioudina, M. V., Dyer, D. C. Pharmacological characterization of alpha1-adrenoceptor subtypes in the bovine tail artery. J. vet. Pharmacol. Therap. 25, 363-369. The purpose of this study was to identify the alpha1-adrenoreceptor subtypes present in the bovine tail artery which mediate contractions to adrenergic agonists. A61603, an alpha1A-selective agonist, was more potent compared with norepinephrine and phenylephrine. The pKA value of A61603 was 6.93 +/- 0.19 microM (n=6). Antagonists, BMY 7378, WB 4101 and 5-methylurapidil, caused a parallel shift to the right of the concentration-response curve to A61603 with pA2 values of 6.62, 9.27 and 8.86, respectively. Prazosin, BMY 7378 and WB 4101 inhibited phenylephrine induced contraction with pA2 values of 9.47, 7.17 and 9.73, respectively. The pA2 values obtained for 5-methylurapidil, WB 4101, BMY 7378 and prazosin against alpha1-adrenoceptor agonists were significantly correlated with pKi values (Zhu, Zhang & Han, 1997, Eur. J. Pharmacol.329, 55-61) for the cloned alpha1a-adrenoceptor but not with the cloned alpha1b- or alpha1d-adrenoceptor. BMY 7378, a selective alpha1D-adrenoceptor antagonist, was significantly more potent against the nonsubtype selective agonist phenylephrine than to A61603. Chloroethylclonidine (50 microM for 10 min) did not affect contractile responses to A61603, but caused a significant inhibition of contractile responses to phenylephrine. In conclusion, it appears that alpha1A- and alpha1D-adrenoceptors play a role in adrenergic mediated contraction in the bovine tail artery.


Asunto(s)
Agonistas alfa-Adrenérgicos/farmacología , Imidazoles/farmacología , Receptores Adrenérgicos alfa 1/efectos de los fármacos , Tetrahidronaftalenos/farmacología , Vasoconstricción/efectos de los fármacos , Agonistas alfa-Adrenérgicos/administración & dosificación , Agonistas alfa-Adrenérgicos/sangre , Antagonistas Adrenérgicos alfa/farmacología , Animales , Arterias/efectos de los fármacos , Bovinos , Dioxanos/farmacología , Relación Dosis-Respuesta a Droga , Imidazoles/administración & dosificación , Imidazoles/sangre , Norepinefrina/administración & dosificación , Norepinefrina/sangre , Norepinefrina/farmacología , Fenilefrina/administración & dosificación , Fenilefrina/sangre , Fenilefrina/farmacología , Piperazinas/farmacología , Prazosina/farmacología , Receptores Adrenérgicos alfa 1/clasificación , Cola (estructura animal)/irrigación sanguínea , Tetrahidronaftalenos/administración & dosificación , Tetrahidronaftalenos/sangre
8.
Mol Microbiol ; 43(2): 335-54, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11985713

RESUMEN

We have characterized the interaction of the Neisseria meningitidis TonB-dependent receptor HpuAB with haemoglobin (Hb). Protease accessibility assays indicated that HpuA and HpuB are surface exposed, HpuB interacts physically with HpuA, and TonB energization affects the conformation of HpuAB. Binding assays using [125I]-Hb revealed that the bipartite receptor has a single binding site for Hb (Kd 150 nM). Competitive binding assays using heterologous Hbs revealed that HpuAB Hb recognition was not species specific. The binding kinetics of Hb to HpuAB were dramatically altered in a TonB- mutant and in wild-type meningococci treated with the protonophore carbonylcyanide m-chlorophenylhydrazone (CCCP), indicating that TonB and an intact proton motive force are required for normal Hb binding and release from HpuAB. Our results support a model in which both HpuA and HpuB are required to form a receptor complex in the outer membrane with a single binding site, whose structure and ligand interactions are significantly affected by the TonB-mediated energy state of the receptor.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas/metabolismo , Hemoglobinas/metabolismo , Proteínas de la Membrana/metabolismo , Neisseria meningitidis/metabolismo , Receptores de Superficie Celular/metabolismo , Proteínas de la Membrana Bacteriana Externa/genética , Cinética , Ligandos , Neisseria meningitidis/genética , Neisseria meningitidis/crecimiento & desarrollo , Receptores de Superficie Celular/genética , Tripsina/metabolismo
9.
Mol Ecol ; 10(5): 1165-77, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11380875

RESUMEN

A dominant plant of the California grasslands, purple needlegrass [Nassella pulchra (Hitchc.) Barkworth] is an important revegetation species in its native range. The amplified fragment length polymorphism (AFLP) method was used to elucidate mode of reproduction and nucleotide variation among 11 natural populations and three selected natural germplasm releases of N. pulchra. A total of 12 co-dominant AFLPs, informative within eight populations, failed to reveal any heterozygous individuals, indicating very high selfing rates (S(H)=1). Estimates of nucleotide diversity within populations ranged from 0 to 0.00069 (0.00035 average), whereas the total nucleotide divergence among populations ranged from 0.00107 to 0.00382 (0.00247 average). Measures of population differentiation (GS) in terms of Shannon-Weaver diversity values and estimated nucleotide substitutions were 0.90 and 0.86, respectively. Although some of the sample populations contained a mixture of true breeding genotypes, most populations could be distinguished unambiguously. Moreover, geographical distance between the natural source populations was significantly correlated with genetic distance (r = 0.60) among the corresponding sample populations. Results indicate that inbreeding, combined with founder effects and/or selection, has contributed to the differentiation of N. pulchra populations. Foundation seed populations of the selected natural germplasm releases were genetically well defined and most similar to natural seed collected near the corresponding source populations. Thus, these commercial germplasm sources will be made practically available and useful for conservation plantings within the intended areas of utilization.


Asunto(s)
Variación Genética , Poaceae/genética , Polimorfismo Genético , California , Poaceae/fisiología , Polimorfismo de Nucleótido Simple , Reproducción/fisiología
10.
Infect Immun ; 69(4): 2137-43, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11254568

RESUMEN

One means by which Bordetella bronchiseptica scavenges iron is through production of the siderophore alcaligin. A nonrevertible alcaligin mutant derived from the virulent strain 4609, designated DBB25, was constructed by insertion of a kanamycin resistance gene into alcA, one of the genes essential for alcaligin biosynthesis. The virulence of the alcA mutant in colostrum-deprived, caesarean-delivered piglets was compared with that of the parent strain in two experiments. At 1 week of age, piglets were inoculated with phosphate-buffered saline, 4609, or DBB25. Two piglets in each group were euthanatized on day 10 postinfection. The remainder were euthanatized at 21 days postinfection. Clinical signs, including fever, coughing, and sneezing, were present in both groups. Nasal washes performed 7, 14, and 21 days postinoculation demonstrated that strain DBB25 colonized the nasal cavity but did so at levels that were significantly less than those achieved by strain 4609. Analysis of colonization based on the number of CFU per gram of tissue recovered from the turbinate, trachea, and lung also demonstrated significant differences between DBB25 and 4609, at both day 10 and day 21 postinfection. Mild to moderate turbinate atrophy was apparent in pigs inoculated with strain 4609, while turbinates of those infected with strain DBB25 developed no or mild atrophy. We conclude from these results that siderophore production by B. bronchiseptica is not essential for colonization of swine but is required for maximal virulence. B. bronchiseptica mutants with nonrevertible defects in genes required for alcaligin synthesis may be candidates for evaluation as attenuated, live vaccine strains in conventionally reared pigs.


Asunto(s)
Bordetella bronchiseptica/patogenicidad , Ácidos Hidroxámicos , Sideróforos/fisiología , Animales , Animales Recién Nacidos , Infecciones por Bordetella/etiología , Infecciones por Bordetella/patología , Pulmón/microbiología , Pulmón/patología , Mutación , Cavidad Nasal/microbiología , Porcinos , Virulencia
12.
J Clin Periodontol ; 28(2): 121-7, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11168736

RESUMEN

BACKGROUND AND AIMS: A limited amount of data using flat trim multitufted toothbrushes shows that abrasion of substrate surfaces by a standard toothpaste varies dependent on filament stiffness and configuration; soft brushes producing the most abrasion. The aims of these studies in vitro were to assess toothpaste abrasion of acrylic and stain removal by 5 proprietary medium toothbrushes with different head filament arrangements, and a prototype brush with rectangular filaments. The prototype brush had a medium texture in the long axis and soft texture at right angles to the long axis. MATERIAL AND METHOD: Optically clear acrylic was used as the substrate for abrasion by a standard toothpaste. Loss of substrate was determined by profilometry after 5000, 10000, 15000 and 20000 linear or rotary brushing actions. Stain removal was determined spectrophotometrically from optically clear acrylic specimens stained by chlorhexidine tea soaking sequences. Stained specimens were brushed with water using linear or rotary actions and measurements taken every 10 s to 60 s. RESULTS: Abrasion was progressive with increasing strokes and the pattern for each brush and brush action was to a first approximation linear. Overall, abrasion was significantly greater with linear compared to rotary action. Also overall brushes differed in the abrasion produced with both actions and particularly at greater exposure times. Within brush differences for the two motions were all significant by 20000 strokes except for the prototype brush. Stain removal was progressive over time with each brush but the pattern was non-linear. For the proprietary brushes the rotary motion removed less stain. For the prototype brush more stain was removed with the rotary action. Overall brushes differed significantly in stain removal within each motion and for each motion most differences between the proprietary and prototype brushes reached significance. CONCLUSIONS: The differences between brushes for both abrasion and stain removal must in large part relate to the filament contact area with the substrate surface. Whilst the model may not be predictive of clinical differences, it could find use to establish minimum criteria for toothbrush action.


Asunto(s)
Abrasión de los Dientes/etiología , Decoloración de Dientes/terapia , Cepillado Dental/efectos adversos , Cepillado Dental/instrumentación , Resinas Acrílicas , Análisis de Varianza , Humanos , Estadísticas no Paramétricas , Cepillado Dental/métodos , Pastas de Dientes/efectos adversos
13.
J Sch Nurs ; 17(5): 258-65, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11885342

RESUMEN

Hand washing is the most effective way to prevent the spread of communicable disease. The purpose of this double-blind, placebo-controlled study was to assess whether an alcohol-free, instant hand sanitizer containing surfactants, allantoin, and benzalkonium chloride could reduce illness absenteeism in a population of 769 elementary school children and serve as an effective alternative when regular soap and water hand washing was not readily available. Prior to the study, students were educated about proper hand washing technique, the importance of hand washing to prevent transmission of germs, and the relationship between germs and illnesses. Children in kindergarten through the 6th grade (ages 5-12) were assigned to the active or placebo hand-sanitizer product and instructed to use the product at scheduled times during the day and as needed after coughing or sneezing. Data on illness absenteeism were tracked. After 5 weeks, students using the active product were 33% less likely to have been absent because of illness when compared with the placebo group.


Asunto(s)
Absentismo , Desinfección de las Manos , Educación en Salud , Servicios de Enfermería Escolar , Niño , Preescolar , Método Doble Ciego , Humanos , Modelos Teóricos , Placebos , Distribución Aleatoria , Investigación
14.
Fam Med ; 32(9): 633-8, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11039151

RESUMEN

UNLABELLED: BACKGROUND AND HYPOTHESES: A substantial percentage of school absenteeism among children is related to transmissible infection. Rates of transmission can be reduced by hand washing with soap and water, but such washing occurs infrequently. This study tested whether an alcohol-free instant hand sanitizer (CleanHands) could reduce illness absenteeism in school-age children. METHODS: A 10-week, open-label, crossover study was performed on 420 elementary school-age children (ages 5-12). Students were given a brief orientation immediately prior to the start of the study on the relationship of germs, illness, and hand washing. Each student in the treatment group then received the test product in individual bottles, with instructions to apply one to two sprays to the hands after coming into the classroom, before eating, and after using the restroom, in addition to their normal hand washing with soap and water. The control group was instructed to continue hand washing as normal with non-medicated soap. After 4 weeks of treatment and a 2-week wash-out period, the control and experimental groups were reversed. Data gathered on absenteeism were classified as gastrointestinal or respiratory related and normalized for nonillness-related absenteeism and school holidays. RESULTS: Compared to the hand washing-only control group, students using CleanHands were found to have 41.9% fewer illness-related absence days, representing a 28.9% and a 49.7% drop in gastrointestinal- and respiratory-related illnesses, respectively. Likewise, absence incidence decreased by 31.7%, consisting of a 44.2% and 50.2% decrease in incidence of gastrointestinal- and respiratory-related illnesses, respectively. No adverse events were reported during the study. CONCLUSIONS: Daily use of the instant hand sanitizer was associated with significantly lower rates of illness-related absenteeism.


Asunto(s)
Absentismo , Enfermedades Gastrointestinales/prevención & control , Desinfección de las Manos , Enfermedades Respiratorias/prevención & control , Saneamiento , Estudiantes , Niño , Estudios Cruzados , Humanos
15.
J Trauma ; 48(4): 673-82; discussion 682-3, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10780601

RESUMEN

BACKGROUND: Thoracic aortic injury (TAI) is a devastating condition in which prompt recognition can obviate morbidity and mortality. It is a long-held belief that TAI is more likely when there is a "major mechanism of injury." The purposes of this prospective study were to determine mechanism characteristics that are predictive of TAI and to evaluate chest computed tomography (CT) as a screening tool for TAI. METHODS: Over a 5 1/2 year period, blunt chest trauma patients at two Level I trauma centers were evaluated for potential TAI. Patients were assigned mechanism and radiograph scores from 1 (low suspicion for TAI) to 5 (very high suspicion for TAI). Immediate aortography was obtained when suspicion for TAI was very high. The remaining patients were evaluated with contrast-enhanced chest CT. Confirmatory aortography was obtained on all positive chest CT scans and on all patients with mechanism scores of 4 or 5 even if the CT was negative. Mechanism and radiographic data were correlated with the results of aortic imaging. RESULTS: Of the 1,561 patients evaluated for TAI, 30 aortic injuries were found. The assessment of mechanism was imperfect with a reliance on often incomplete and subjective data. The subjective mechanism score proved to be the most useful predictor of TAI. Radiographic scores were useful but insensitive for intimal injuries. Computed tomography was found to have 100% and 100% NPV for TAI. CONCLUSION: Considering the inherent difficulties in identifying patients at risk for TAI and the effectiveness of chest CT as a screening tool for aortic injury, we recommend liberal use of chest CT in blunt chest trauma. Guidelines for determining the need for aortic imaging are outlined.


Asunto(s)
Aorta Torácica/diagnóstico por imagen , Aorta Torácica/lesiones , Tomografía Computarizada por Rayos X , Heridas no Penetrantes/diagnóstico por imagen , Heridas no Penetrantes/etiología , Accidentes por Caídas , Accidentes de Tránsito , Aortografía , Femenino , Humanos , Masculino , Estudios Prospectivos , Radiografía Torácica
16.
J Clin Periodontol ; 27(2): 99-103, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10703654

RESUMEN

BACKGROUND: Loss of dentine at the buccal cervical region of teeth has a multifactorial aetiology. However, a considerable amount of circumstantial evidence, supported by laboratory experiments, implicates toothbrushing with toothpaste as a consistent factor. Most interest has centred around the abrasivity of toothpastes, particularly since a toothbrush alone has negligible effects on dentine. The influence of filament stiffness on toothpaste abrasion was the subject of some studies, mostly at least 2 decades ago, and produced conflicting conclusions. Numerous changes to toothbrush design and construction have taken place in recent years. AIMS: The aim of this study was to measure the abrasion of a standard substrate, acrylic, by a standard toothpaste carried on modern brands of toothbrushes classified by manufacturers as hard (3 brands), medium (3 brands) and soft (6 brands). METHOD: The substrate was brushed for 20,000 strokes with at least 6 heads from each brand. Measurements of substrate loss were made at 5000 stroke increments by profilometry. RESULTS: Substrate loss for all brushes showed a pattern of abrasion which was to a first approximation linear. Overall, hard brushes caused least abrasion and soft brushes the most, with differences between groups being significant. Within-group differences between brands reached significance for soft and medium brushes but not hard brushes. CONCLUSIONS: The results could be explained by increased retention of toothpaste by smaller diameter filaments and denser tufts on soft brushes and the greater flexion of filaments increasing the area of contact with the surface. Calculations on the clinical outcome of these data in vitro indicate that toothbrushing with toothpaste alone would produce minimal damage to dentine even over many years. Differences between brushes therefore are probably of little clinical significance. Certainly, the data do not support the use of hard brushes, particularly in view of the potential detrimental effects to gingival tissues.


Asunto(s)
Abrasión de los Dientes/etiología , Cepillado Dental/efectos adversos , Pastas de Dientes/efectos adversos , Dureza , Humanos , Técnicas In Vitro , Abrasión de los Dientes/patología , Cepillado Dental/instrumentación , Cepillado Dental/estadística & datos numéricos
17.
Radiology ; 213(1): 195-202, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10540662

RESUMEN

PURPOSE: To determine whether chest computed tomography (CT) can be used to exclude aortic injury. MATERIALS AND METHODS: Patients in whom there was very high suspicion of traumatic aortic injury were examined with aortography only. Other patients were examined with contrast material-enhanced CT. Follow-up aortography was performed in all patients with moderate to high suspicion of traumatic aortic injury and in all patients with CT scans that were positive for traumatic aortic injury. CT scans were regarded as positive when they showed mediastinal hematoma or direct findings of aortic injury. During a 4 1/2-year period, 1,009 patients (263 female, 746 male; age range, 3-90 years) were evaluated for possible traumatic aortic injury. RESULTS: Of the 207 patients who underwent aortography directly without CT, 10 had traumatic aortic injury. Of the 802 patients who were examined with CT, 382 underwent follow-up aortography. In this group, there were 10 true-positive and no false-negative CT scans. CT had 100% sensitivity and a 100% negative predictive value for the detection of traumatic aortic injury.


Asunto(s)
Aorta/lesiones , Aortografía , Radiografía Torácica , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aortografía/economía , Niño , Preescolar , Medios de Contraste , Costos y Análisis de Costo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Radiografía Torácica/economía , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/economía
18.
AJR Am J Roentgenol ; 173(1): 53-8, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10397099

RESUMEN

OBJECTIVE: In a multicenter study, we evaluated the relationships between the extent and severity of bronchiectasis on CT and clinical symptoms, spirometric abnormality, and sputum characteristics. SUBJECTS AND METHODS: The study population included 261 patients with symptomatic, physiologically significant bronchiectasis, who were enrolled in another study evaluating the clinical efficacy of deoxyribonudease in treatment of bronchiectasis. Patients with cystic fibrosis, allergic bronchopulmonary aspergillosis, and fungal or mycobacterial infection were excluded. In addition to high-resolution CT scanning, all patients underwent clinical evaluation, spirometry, and sputum culture. CT features scored by consensus of two observers included the extent of bronchiectasis, type of bronchiectasis (cylindric, varicose, or cystic), extent of mucoid impaction, and degree of bronchial wall thickening. RESULTS: Scores for the severity and extent of bronchiectasis correlated with the forced expiratory volume in 1 sec (FEV1) (r = -.362, p < .0001) and with the forced vital capacity (FVC) (r = -.362, p < .0001). Scores for bronchial wall thickening correlated with the FEV1 (r = -.367, p < .0001) and FVC (r = -.239, p < .001). Patients with cystic bronchiectasis were significantly more likely to grow Pseudomonas from their sputa and to have purulent sputa than were patients with cylindric or varicose bronchiectasis. Patients with cystic bronchiectasis had significantly lower FEV1 and FVC values than did patients with cylindric or varicose bronchiectasis. CONCLUSION: In this patient population, we found weak but significant correlations between the degree of morphologic abnormality on CT and the extent of physiologic impairment. Cystic bronchiectasis was associated with sputum purulence and with the growth of Pseudomonas. CT classification of the type of bronchiectasis may be useful as an index of severity of disease.


Asunto(s)
Bronquiectasia/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Bronquios/patología , Bronquiectasia/diagnóstico , Bronquiectasia/etiología , Femenino , Volumen Espiratorio Forzado , Humanos , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Espirometría , Esputo/microbiología , Capacidad Vital
19.
Protein Sci ; 8(6): 1342-9, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10386884

RESUMEN

The structure of a bifunctional 5,10-methylene-tetrahydrofolate dehydrogenase/cyclohydrolase from Escherichia coli has been determined at 2.5 A resolution in the absence of bound substrates and compared to the NADP-bound structure of the homologous enzyme domains from a trifunctional human synthetase enzyme. Superposition of these structures allows the identification of a highly conserved cluster of basic residues that are appropriately positioned to serve as a binding site for the poly-gamma-glutamyl tail of the tetrahydrofolate substrate. Modeling studies and molecular dynamic simulations of bound methylene-tetrahydrofolate and NADP shows that this binding site would allow interaction of the nicotinamide and pterin rings in the dehydrogenase active site. Comparison of these enzymes also indicates differences between their active sites that might allow the development of inhibitors specific to the bacterial target.


Asunto(s)
Aminohidrolasas/química , Escherichia coli/enzimología , Metilenotetrahidrofolato Deshidrogenasa (NADP)/química , Complejos Multienzimáticos/química , Aminohidrolasas/metabolismo , Sitios de Unión , Cristalografía por Rayos X , Dimerización , Humanos , Metilenotetrahidrofolato Deshidrogenasa (NADP)/metabolismo , Modelos Moleculares , Complejos Multienzimáticos/metabolismo , Conformación Proteica , Tetrahidrofolatos/metabolismo
20.
Mol Microbiol ; 32(5): 977-89, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10361300

RESUMEN

We have previously described HpuAB, a two-component receptor that mediates binding to haemoglobin (Hb), haemoglobin-haptoglobin (Hb-Hp) and apo-haptoglobin (Hp). In this communication, we constructed non-polar mutations in the hpuA and hpuB loci to examine the individual roles of HpuA and HpuB. Our results indicate that both HpuA and HpuB are required for the acquisition of Fe from Hb and Hb-Hp. We isolated Hb utilization-positive (Hb+) variants of our Hb utilization-negative (Hb-) hpu mutants at a frequency of 10(-3) and demonstrated that the Hb+ phenotype resulted from the expression of a second Hb receptor, HmbR. Expression of HmbR in DNM2 was found to be controlled by translational frameshifting involving a polyguanine (G) tract located within the hmbR locus. The hpuA locus also contains a poly(G) tract, which suggested that meningococci could phase vary each Hb receptor independently by slip-strand mispairing in the poly(G) tracts found in hpuA and hmbR. Thus, we isolated a naturally occurring Hb- variant of DNM2, designated DNM2 Hb-, which did not express either HpuAB or HmbR. Hb+ variants of DNM2Hb- were selected and examined for HpuAB and HmbR expression. In each instance, acquisition of HpuAB or HmbR expression was correlated with phase variation in the poly(G) tract of each Hb receptor.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa/metabolismo , Hemoglobinas/metabolismo , Hierro/metabolismo , Neisseria meningitidis/metabolismo , Receptores de Superficie Celular/metabolismo , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Western Blotting , Haptoglobinas/metabolismo , Datos de Secuencia Molecular , Mutagénesis Insercional , Neisseria meningitidis/genética , Neisseria meningitidis/crecimiento & desarrollo , Receptores de Superficie Celular/genética
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