RESUMEN
Seasonal trends and the parasitoid complex of Chinese wax scale (Ceroplastes sinensis) was studied from July 2010 to February 2013. Six commercial citrus groves located in northeastern Spain were sampled fortnightly. Chinese wax scale completed a single annual generation. Egg oviposition started in May and continued until mid-July. Egg hatching began in mid-June, and in the first quarter of August, the maximum percentage of hatched eggs was reached. In the same groves, the parasitoid species of C. sinensis were determined together with their seasonal trends, relative abundance and occurrence on C. sinensis. Four hymenoptera were found parasitizing C. sinensis, mainly on third instars and females: Coccophagus ceroplastae (Aphelinidae), Metaphycus helvolus (Encyrtidae), Scutellista caerulea (Pteromalidae) and Aprostocetus ceroplastae (Eulophidae). The most abundant species was A. ceroplastae, corresponding to 54% of the parasitoids emerged. Coccophagus ceroplastae and M. helvolus represented 19%, whereas S. caerulea comprised 8% of the total. This study is the first published record of C. ceroplastae in Spain and the first record of M. helvolus on C. sinensis in Spain. Concerning the economical thresholds normally used, sampling plans developed for the management of C. sinensis in citrus groves should target population densities of around 12-20% of invaded twigs, equivalent to 0.2-0.5 females per twig. The sample size necessary to achieve the desired integrated pest management precision is 90-160 twigs per grove for the enumerative plan and about 160-245 twigs per grove for the binomial plan.
Asunto(s)
Hemípteros/fisiología , Control Biológico de Vectores/métodos , Estaciones del Año , Avispas/fisiología , Animales , Citrus/fisiología , Citrus sinensis/fisiología , Femenino , Hemípteros/parasitología , Larva/fisiología , Masculino , Ninfa , Dinámica Poblacional , Tamaño de la Muestra , España , Manejo de Especímenes , Avispas/crecimiento & desarrolloRESUMEN
Tetranychus urticae is a key pest of citrus in Spain, especially of clementine mandarin trees. The effects of this mite on fruit production were assessed in 24 clementine trees for three consecutive years. Trees were visited weekly and spider mite and phytoseiid mite populations and leaf flush patterns were estimated. At the end of the season, mandarins were harvested, weighed, and mite damage (scarring on the fruit) characterized. Negative relationships between spider mite density and yield (kg/tree) and fruit damage (% scarred fruit rind) were found. The multivariate regressions highlighted the key role of phytoseiid mites and leaf flush patterns, which were negatively related to fruit damage. The shortest sampling period that satisfactorily predicted fruit damage at harvest, extended from August to mid-October. For IPM purposes, an action threshold of 31.1 mites m⻲ of symptomatic leaf was estimated. Taking into account spider mite dynamics, the economic threshold ranged from 10 to 15 mites m⻲ of symptomatic leaf. When this threshold is exceeded growers would have a 1-week window to apply the control technologies against T. urticae of their choice.
Asunto(s)
Citrus , Frutas , Control de Insectos/economía , Tetranychidae , Animales , Citrus/economía , Femenino , Frutas/economíaRESUMEN
In the present study, we quantified the proportion of skeletal involvement of Paget disease of bone (PDB) not captured by an abdominal X-ray. We also analyzed extension and severity over time and tested the hypothesis that X-rays from selected areas could replace bone scans for mapping PBD. We examined whole skeletal (99m)TC-MDP bone scans from 208 consecutive untreated patients. Pagetic bones included in an abdominal X-ray were delimited; disease extension and activity were calculated using Coutris's index as well as Renier's index and serum alkaline phosphatase (AP) values, respectively. The study period (1965-2007) was divided into quartiles according to the date of the diagnosis. The percentage of patients with PDB captured by an abdominal X-ray was 79 % (95 % CI 74-85 %). In the last quartile vs. the first quartile, PDB was diagnosed at a more advanced age (67 ± 11 vs. 57 ± 9 years, respectively), with a lower median extension (4 vs. 7) and similar median activity (32 vs. 35) but less activity through median AP values (183 vs. 485 UI/L). The skeletal locations to X-ray in order to capture up to 93 % of PDB extension were the abdomen, skull with facial bones, and both tibias. In conclusion, one-fifth of patients are underdiagnosed when assessing prevalence of PDB by an X-ray of the abdomen, and there is a secular trend to presentation in older patients with a decreasing extension of the disease. A set of X-rays that includes abdomen, skull with facial bones, and both tibias provides a reliable alternative to bone scans.
Asunto(s)
Huesos/diagnóstico por imagen , Osteítis Deformante/diagnóstico por imagen , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteítis Deformante/epidemiología , Cintigrafía , Cráneo/diagnóstico por imagen , Tibia/diagnóstico por imagenRESUMEN
The adult body size of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (Diptera: Tephritidae), varies in natural conditions. Body size is an important fitness indicator in the Mediterranean fruit fly; larger individuals are more competitive at mating and have a greater dispersion capacity and fertility. Both temperature during larval development and host fruit quality have been cited as possible causes for this variation. We studied the influence of host fruit and temperature during larval development on adult body size (wing area) in the laboratory, and determined body size variation in field populations of the Mediterannean fruit fly in eastern Spain. Field flies measured had two origins: 1) flies periodically collected throughout the year in field traps from 32 citrus groves, during the period 2003-2007; and 2) flies evolved from different fruit species collected between June and December in 2003 and 2004. In the lab, wing area of male and female adults varied significantly with temperature during larval development, being larger at the lowest temperature. Adult size also was significantly different depending on the host fruit in which larvae developed. The size of the flies captured at the field, either from traps or from fruits, varied seasonally showing a gradual pattern of change along the year. The largest individuals were obtained during winter and early spring and the smallest during late summer. In field conditions, the size of the adult Mediterannean fruit fly seems apparently more related with air temperature than with host fruit. The implications of this adult size pattern on the biology of C. capitata and on the application of the sterile insect technique are discussed.
Asunto(s)
Tamaño Corporal , Citrus/parasitología , Prunus/parasitología , Temperatura , Tephritidae/crecimiento & desarrollo , Animales , Femenino , Interacciones Huésped-Patógeno , Larva/crecimiento & desarrollo , MasculinoRESUMEN
Stromal-epithelial interactions dictate prostate tumorigenesis and response to castration. Hydrogen peroxide-inducible clone 5 (Hic-5/ARA55) is a transforming growth factor-beta (TGF-ß)-induced coactivator of androgen receptor (AR) expressed in the prostate stroma. Interestingly, following castration, we identified epithelial expression of Hic-5/ARA55 in mouse and human prostate tissues. To determine the role of epithelial Hic-5 in prostate cancer progression and castration responsiveness, we compared LNCaP cells having Hic-5 stably expressed with the parental LNCaP cells following tissue recombination xenografts with mouse prostate stromal cells. We previously identified knocking out prostate stromal TGF-ß signaling potentiated castrate-resistant prostate tumors, in a Wnt-dependent manner. The LNCaP chimeric tumors containing prostate fibroblasts conditionally knocked out for the TGF-ß type II receptor (Tgfbr2-KO) resulted in larger, more invasive, and castration-resistant tumors compared those with floxed (control) stromal cells. However, the LNCaP-Hic5 associated with Tgfbr2-KO fibroblasts generated chimeric tumors with reduced tumor volume, lack of invasion and restored castration dependence. Neutralization of canonical Wnt signaling is shown to reduce prostate tumor size and restore regression following castration. Thus, we hypothesized that epithelial Hic-5/ARA55 expression negatively regulated Wnt signaling. The mechanism of the Hic-5/ARA55 effects on castration was determined by analysis of the c-myc promoter. C-myc luciferase reporter activity suggested Hic-5/ARA55 expression inhibited c-myc activity by ß-catenin. Sequential ChIP analysis indicated ß-catenin and T-cell-specific 4 (TCF4) bound the endogenous c-myc promoter in the absence of Hic-5 expression. However, the formation of a TCF4/Hic-5 repressor complex inhibited c-myc promoter activity, by excluding ß-catenin binding with TCF4 on the promoter. The data indicate Hic-5/ARA55 expression in response to castration-enabled epithelial regression through the repression of c-myc gene at the chromatin level.
Asunto(s)
Transformación Celular Neoplásica/patología , Proteínas del Citoesqueleto/metabolismo , Proteínas de Unión al ADN/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias de la Próstata/patología , Animales , Factores de Transcripción Básicos con Cremalleras de Leucinas y Motivos Hélice-Asa-Hélice/metabolismo , Línea Celular Tumoral , Transformación Celular Neoplásica/metabolismo , Genes myc , Humanos , Proteínas con Dominio LIM , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones SCID , Orquiectomía , Regiones Promotoras Genéticas , Neoplasias de la Próstata/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Receptor Tipo II de Factor de Crecimiento Transformador beta , Receptores Androgénicos/metabolismo , Receptores de Factores de Crecimiento Transformadores beta/metabolismo , Células del Estroma/metabolismo , Células del Estroma/patología , Factor de Transcripción 4 , Factores de Transcripción/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismoRESUMEN
La osteonecrosis, también conocida como necrosis avascular, se ha asociado a numerosos procesos. Su patogenia y, especialmente, su tratamiento son motivo de controversia. En este artículo se revisan la etiología y la patogenia de la osteonecrosis y sus principales opciones terapéuticas (AU)
Osteonecrosis, also known as aseptic necrosis, is a pathological process that has been associated with numerous conditions. The pathogenesis of osteonecrosis and especially the treatment both remain an area of controversy. In this article we review the etiology and pathogenesis of osteonecrosis as well as the main therapeutic options (AU)
Asunto(s)
Humanos , Osteonecrosis/epidemiología , Artroplastia de Reemplazo , Lupus Eritematoso Sistémico/complicaciones , Glucocorticoides/efectos adversos , Tacrolimus/uso terapéutico , Factores de Riesgo , Difosfonatos/uso terapéuticoRESUMEN
Osteonecrosis, also known as aseptic necrosis, is a pathological process that has been associated with numerous conditions. The pathogenesis of osteonecrosis and especially the treatment both remain an area of controversy. In this article we review the etiology and pathogenesis of osteonecrosis as well as the main therapeutic options.
RESUMEN
Tetranychus urticae Koch (Acari: Tetranychidae) is an important pest of clementine mandarins, Citrus reticulata Blanco, in Spain. As a first step toward the development of an integrated crop management program for clementines, dispersion patterns of T. urticae females were determined for different types of leaves and fruit. The study was carried out between 2001 and 2003 in different commercial clementine orchards in the provinces of Castelló and Tarragona (northeastern Spain). We found that symptomatic leaves (those exhibiting typical chlorotic spots) harbored 57.1% of the total mite counts. Furthermore, these leaves were representative of mite dynamics on other leaf types. Therefore, symptomatic leaves were selected as a sampling unit. Dispersion patterns generated by Taylor's power law demonstrated the occurrence of aggregated patterns of spatial distribution (b > 1.21) on both leaves and fruit. Based on these results, the incidence (proportion of infested samples) and mean density relationship were developed. We found that optimal binomial sample sizes for estimating low populations of T. urticae on leaves (up to 0.2 female per leaf) were very large. Therefore, enumerative sampling would be more reliable within this range of T. urticae densities. However, binomial sampling was the only valid method for estimating mite density on fruit.
Asunto(s)
Citrus/parasitología , Tetranychidae , Animales , Femenino , Frutas/parasitología , Modelos Biológicos , Hojas de la Planta/parasitología , Densidad de Población , Tamaño de la MuestraRESUMEN
The Wider system is a newly developed computer-assisted image-processing device for both bacterial identification and antimicrobial susceptibility testing. It has been adapted to be able to read and interpret commercial MicroScan panels. Two hundred forty-four fresh consecutive clinical isolates (138 isolates of the family Enterobacteriaceae, 25 nonfermentative gram-negative rods [NFGNRs], and 81 gram-positive cocci) were tested. In addition, 100 enterobacterial strains with known beta-lactam resistance mechanisms (22 strains with chromosomal AmpC beta-lactamase, 8 strains with chromosomal class A beta-lactamase, 21 broad-spectrum and IRT beta-lactamase-producing strains, 41 extended-spectrum beta-lactamase-producing strains, and 8 permeability mutants) were tested. API galleries and National Committee for Clinical Laboratory Standards (NCCLS) microdilution methods were used as reference methods. The Wider system correctly identified 97.5% of the clinical isolates at the species level. Overall essential agreement (+/-1 log(2) dilution for 3,719 organism-antimicrobial drug combinations) was 95.6% (isolates of the family Enterobacteriaceae, 96.6%; NFGNRs, 88.0%; gram-positive cocci, 95.6%). The lowest essential agreement was observed with Enterobacteriaceae versus imipenem (84.0%), NFGNR versus piperacillin (88.0%) and cefepime (88.0%), and gram-positive isolates versus penicillin (80.4%). The category error rate (NCCLS criteria) was 4.2% (2.0% very major errors, 0.6% major errors, and 1. 5% minor errors). Essential agreement and interpretive error rates for eight beta-lactam antibiotics against isolates of the family Enterobacteriaceae with known beta-lactam resistance mechanisms were 94.8 and 5.4%, respectively. Interestingly, the very major error rate was only 0.8%. Minor errors (3.6%) were mainly observed with amoxicillin-clavulanate and cefepime against extended-spectrum beta-lactamase-producing isolates. The Wider system is a new reliable tool which applies the image-processing technology to the reading of commercial trays for both bacterial identification and susceptibility testing.
Asunto(s)
Bacterias/clasificación , Infecciones Bacterianas/microbiología , Técnicas de Tipificación Bacteriana/instrumentación , Procesamiento de Imagen Asistido por Computador/instrumentación , Procesamiento de Imagen Asistido por Computador/métodos , Pruebas de Sensibilidad Microbiana/instrumentación , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Enterobacteriaceae/clasificación , Enterobacteriaceae/efectos de los fármacos , Estudios de Evaluación como Asunto , Humanos , Estándares de Referencia , Resistencia betalactámicaRESUMEN
The activities of ampicillin-sulbactam and amoxicillin-clavulanate were studied with 100 selected clinical Escherichia coli isolates with different beta-lactam susceptibility phenotypes by standard agar dilution and disk diffusion techniques and with a commercial microdilution system (PASCO). A fixed ratio (2:1) and a fixed concentration (clavulanate, 2 and 4 micrograms/ml; sulbactam, 8 micrograms/ml) were used in the agar dilution technique. The resistance frequencies for amoxicillin-clavulanate with different techniques were as follows: fixed ratio agar dilution, 12%; fixed concentration 4-micrograms/ml agar dilution, 17%; fixed ratio microdilution, 9%; and disk diffusion, 9%. Marked discrepancies were found when these results were compared with those obtained with ampicillin-sulbactam (26 to 52% resistance), showing that susceptibility to amoxicillin-clavulanic acid cannot be predicted by testing the isolate against ampicillin-sulbactam. Interestingly, the discrimination between susceptible and intermediate isolates was better achieved with 4 micrograms of clavulanate per ml than with the fixed ratio. In contrast, amoxicillin susceptibility was not sufficiently restored when 2 micrograms of clavulanate per ml was used, particularly in moderate (mean beta-lactamase activity, 50.8 mU/mg of protein) and high-level (215 mU/mg) TEM-1 beta-lactamase producer isolates. Four micrograms of clavulanate per milliliter could be a reasonable alternative to the 2:1 fixed ratio, because most high-level beta-lactamase-hyperproducing isolates would be categorized as nonsusceptible, and low- and moderate-level beta-lactamase-producing isolates would be categorized as nonresistant. This approach cannot be applied to sulbactam, either with the fixed 2:1 ratio or with the 8-micrograms/ml fixed concentration, because many low-level beta-lactamase-producing isolates would be classified in the resistant category. These findings call for a review of breakpoints for beta-lactam-beta-lactamase inhibitors combinations.
Asunto(s)
Quimioterapia Combinada/farmacología , Escherichia coli/efectos de los fármacos , Resistencia betalactámica/fisiología , Amoxicilina/farmacología , Ampicilina/farmacología , Ácido Clavulánico/farmacología , Escherichia coli/enzimología , Escherichia coli/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana , Fenotipo , Sulbactam/farmacología , beta-Lactamasas/metabolismoRESUMEN
The emergence of clinical methicillin-resistant Staphylococcus aureus with reduced susceptibility to glycopeptides has recently been documented. Heterogeneous levels of glycopeptides susceptibility have been demonstrated in these isolates. Prospectively, we investigated the presence of S. aureus isolates with reduced susceptibility to vancomycin in our hospital from October 1997 to January 1998. The vancomycin and teicoplanin susceptibility of 248 consecutively methicillin-susceptible and -resistant S. aureus isolates from clinical and surveillance specimens was studied by broth microdilution and agar dilution methods. In addition, 108 CFU/mI of overnight cultures were plated onto BHI-agar plates containing 6 and 10 microg/ml of vancomycin and were incubated for 48 hours at 35 degrees C. Under these conditions selected colonies were subcultured onto vancomycin plates and vancomycin susceptibility (E-test) was determined again. Vancomycin MIC(90) values by the agar dilution technique for methicillin-susceptible and -resistant isolates were 2 and 4 microg/ml, respectively No selected colonies were observed on 10 microg/ml vancomycin plates. In contrast, 12 isolates, including 8 (3.9%) methicillin-susceptible and 4 (9. 1%) methicillin-resistant isolates, showed subpopulations at a frequency rate of 10(-6)-10(-7) on 6 microg/ml vancomycin plates. Nevertheless, a significant increase in MIC values for vancomycin was not observed in these S. aureus subpopulations.
Asunto(s)
Antibacterianos/farmacología , Resistencia a la Meticilina , Staphylococcus aureus/efectos de los fármacos , Teicoplanina/farmacología , Resistencia a la Vancomicina , Humanos , Pruebas de Sensibilidad Microbiana , Estudios ProspectivosRESUMEN
The in-vitro effects of several concentrations of Ureaplasma urealyticum on the motility, membrane integrity and morphology of washed spermatozoa from healthy donors were studied. A significant reduction in sperm motility and signs of membrane alteration, directly related to U.urealyticum concentration and contact time were observed. Scanning electron microscopy examination showed masses of U. urealyticum attached to the head and middle piece of some of deformed spermatozoa. It is suggested that U.urealyticum is involved in sperm changes leading to male infertility, particularly when there is heavy U. urealyticum colonization or specific infections with this microorganism.
Asunto(s)
Motilidad Espermática , Espermatozoides/microbiología , Ureaplasma urealyticum/patogenicidad , Adhesión Bacteriana , Permeabilidad de la Membrana Celular , Humanos , Técnicas In Vitro , Infertilidad Masculina/etiología , Infertilidad Masculina/patología , Infertilidad Masculina/fisiopatología , Masculino , Microscopía Electrónica de Rastreo , Presión Osmótica , Espermatozoides/fisiología , Espermatozoides/ultraestructura , Infecciones por Ureaplasma/complicaciones , Infecciones por Ureaplasma/patología , Infecciones por Ureaplasma/fisiopatologíaRESUMEN
MIC values and inhibition zone diameters for penicillin, cefotaxime, and erythromycin where determined in 75 consecutive Streptococcus pneumoniae blood isolates by microdilution (PASCO), disc-diffusion and Etest. Using the Etest, 40% and 29.3% of the isolates showed low- or high-level resistance to penicillin and erythromycin respectively, whereas 9.3% were intermediate to cefotaxime. No high-level resistance to cefotaxime was found. No errors were found with the comparison of penicillin and cefotaxime results by microdilution and Etest, with just 2 (2.7%) and 3 (4%) minor errors appearing respectively. On the other hand, when comparing penicillin susceptibility results by disc-diffusion (1 mg oxacillin disc) and Etest, 6 (8%) major errors and 18 (24%) minor errors were found.
Asunto(s)
Antibacterianos/farmacología , Pruebas de Sensibilidad Microbiana/métodos , Streptococcus pneumoniae/efectos de los fármacos , Medios de Cultivo , Difusión , Técnicas de Dilución del IndicadorRESUMEN
OBJECTIVES: To identify characteristics associated with methicillin-resistant Staphylococcus aureus (MRSA) colonization and infection, and to evaluate the efficacy of systemic and topical antimicrobials in the eradication of MRSA carriage among hospitalized patients. DESIGN: A case-control study was done to identify associations. Odds ratios were estimated by unconditional multiple logistic regression. Cohort study was done to evaluate MRSA decolonization efficacy by an oral regimen. Patients infected or colonized with MRSA received a 5-day course of oral (160 mg/800 mg) trimethoprim-sulfametroxazole twice daily and 600 mg of rifampin once daily as decolonization treatment. The proportion of MRSA-free patients after decolonization treatment was determined. Persistence of clearing was estimated by the Kaplan-Meier method. SETTING: Ramón y Cajal Hospital, a 1,249-bed, tertiary-care teaching hospital in Madrid, Spain. PATIENTS: One hundred ninety-two patients with hospital-acquired MRSA infection/colonization and 195 MRSA-free random controls. RESULTS: Six factors were associated independently with MRSA infection/colonization: age (every 10 years of age, odds ratio [OR] = 1.3); ward (surgical, OR = 1; medical, OR = 3.1; intensive care unit, OR = 60); previous hospitalization (OR = 6.9); coma (OR = 25.3); invasive procedures (each, OR = 1.7); 3 or more weeks of hospitalization (OR = 3.8). We failed to show antibiotic therapy to be an independent risk factor for MRSA hospital infection/colonization. Overall, MRSA eradication was 64.2% by day 2 to 9 after completion of treatment. Kaplan-Meier product limit survival analysis showed that the probability of remaining MRSA-free was 65.3% (SE = 0.09) at 32 days after completion of treatment. CONCLUSIONS: The results offer a rationale for reduction of MRSA infection/colonization in the hospital by interventions aimed at early identification of patients at higher risk, at prompt discharge of patients, and at preventing dissemination while performing invasive procedures. They also provide estimates of antibiotic treatment efficacy to reduce the reservoir of MRSA in the hospital.
Asunto(s)
Infección Hospitalaria/prevención & control , Resistencia a la Meticilina , Infecciones Estafilocócicas/prevención & control , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Antiinfecciosos/uso terapéutico , Estudios de Casos y Controles , Niño , Estudios de Cohortes , Infección Hospitalaria/tratamiento farmacológico , Infección Hospitalaria/epidemiología , Femenino , Humanos , Incidencia , Tiempo de Internación , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , España/epidemiología , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Procedimientos Quirúrgicos Operativos/efectos adversos , Análisis de SupervivenciaRESUMEN
The binding of acetazolamide, p-fluorobenzensulfonamide, p-toluenesulfonamide, and sulfanilamide to nickel(II)-substituted carbonic anhydrase II has been studied by 1H NMR and electronic absorption spectroscopies. These inhibitors bind to the metal ion forming 1:1 complexes and their affinity constants were determined. The 1H NMR spectra of the formed complexes show a number of isotropically shifted signals corresponding to the histidine ligands. The complexes with benzene-sulfonamides gave rise to very similar 1H NMR spectra. The NMR data suggest that these aromatic sulfonamides bind to the metal ion altering its coordination sphere. In addition, from the temperature dependence of 1H NMR spectra of the p-fluorobenzenesulfonamide adduct, a conformational change is suggested. The T1 values of the meta-like protons of the coordinated histidines have been measured and resonance assignments based on NOE experiments were performed.
Asunto(s)
Anhidrasas Carbónicas/metabolismo , Níquel/metabolismo , Sulfonamidas/metabolismo , Acetazolamida/metabolismo , Animales , Bovinos , Espectroscopía de Resonancia Magnética/métodos , Unión Proteica , Conformación Proteica , Espectrofotometría/métodos , Espectrofotometría UltravioletaRESUMEN
The pH dependence of the apparent affinity constants of perchlorate for cobalt(II)bovine carbonic anhydrase II has been measured by electronic absorption spectroscopy. The obtained data have been analyzed in terms of the ionization of two acidic groups of CoBCAII, and the affinity of perchlorate for the two water-containing species of the enzyme have been estimated. Furthermore, the affinity constants of nitrate, perchlorate, and azide for CoBCAII in the temperature range 5 degrees C-30 degrees C have been determined by spectrophotometric titrations at pH 7. The affinity constants for these ligands decrease with increasing temperatures. The temperature dependence of binding was used to estimate the enthalpy and entropy parameters for the formation of the corresponding 1:1 adducts. The obtained results indicate that binding of these anions to the cobalt enzyme is an enthalpy driven process which is opposed by a moderate entropy change.
Asunto(s)
Inhibidores de Anhidrasa Carbónica/farmacología , Anhidrasas Carbónicas/metabolismo , Cobalto/metabolismo , Animales , Aniones , Azidas/farmacología , Bovinos , Cinética , Matemática , Nitratos/farmacología , Percloratos/farmacología , Espectrofotometría , TermodinámicaRESUMEN
We describe two patients with acute diffuse external otitis (swimmer's otitis) acquired in the Mediterranean shore, with Vibrio alginolyticus recovered from ear fluid. We describe the biochemical profile and sensitivity pattern (MIC) of both strains, comparing it to previously published data. A literature review was also performed, in which we found evidence for increasing concern of V. alginolyticus as an human pathogen. Also there is a need for considering halophilic vibrio as potential pathogens, specially if there is also epidemiologic support.
Asunto(s)
Otitis Externa/microbiología , Natación , Vibriosis/microbiología , Vibrio/aislamiento & purificación , Adulto , Farmacorresistencia Microbiana , Femenino , Infecciones por Bacterias Gramnegativas/complicaciones , Humanos , Incidencia , Masculino , Maryland/epidemiología , Persona de Mediana Edad , Plesiomonas/aislamiento & purificación , Infecciones por Proteus/complicaciones , Proteus mirabilis/aislamiento & purificación , España/epidemiología , Especificidad de la Especie , Infecciones Estafilocócicas/complicaciones , Vibrio/clasificación , Vibrio/efectos de los fármacos , Vibrio/patogenicidad , Vibriosis/complicaciones , Vibriosis/epidemiología , Microbiología del Agua , Xanthomonas/aislamiento & purificaciónRESUMEN
Bacteria-laden skin squames, detached bacterial clumps and isolated bacteria floating in skin fluids are the major infective units in hand and skin transmission of microorganisms. These units have differing ability to colonize new surfaces and may have different susceptibility to antiseptics. MIC-MBC testing on isolated bacteria serves to confirm the expected susceptibility of particular isolates and is useful for surveillance of the evolution of antiseptic resistance; however, it is often unreliable in predicting the in-vivo effect. In-vitro tests aimed at duplicating natural conditions (including the effect of antiseptics on bacterial biofilms, or better, on the different infective units) are under evaluation. Meanwhile, tests involving natural skin surfaces, like the Story test, offer reproducible and useful data.
Asunto(s)
Antiinfecciosos Locales/farmacología , Bacterias/efectos de los fármacos , Mano/microbiología , Pruebas de Sensibilidad Microbiana , Piel/microbiología , Desinfección de las Manos , Humanos , Pruebas de Sensibilidad Microbiana/métodosRESUMEN
The interaction between Cobalt(II)-Bovine Carbonic Anhydrase II and the inhibitors sulphate and chloride have been investigated through 1H NMR and electronic absorption spectroscopies. Both inhibitors bind to the metal ion forming a 1:1 adduct and the corresponding affinity constants have been determined. These inhibitors interact weakly with CoBCA II and this interaction only occurs at low pH values. The T1 values of the meta-like protons of the coordinated histidines have been measured. The coordination number of the metal ion in the adducts is discussed on the basis of temperature dependence of the isotropic shifts, T1, and molar absorbance values.
Asunto(s)
Anhidrasas Carbónicas/metabolismo , Cloruros/metabolismo , Cobalto , Sulfatos/metabolismo , Inhibidores de Anhidrasa Carbónica , Cloruros/farmacología , Concentración de Iones de Hidrógeno , Espectroscopía de Resonancia Magnética , Concentración Osmolar , Espectrofotometría , Sulfatos/farmacología , TemperaturaRESUMEN
Antagonism between fosfomycin and antipseudomonal penicillins, cefotaxime, and ceftriaxone was observed in Pseudomonas aeruginosa RYC212. Fosfomycin, a non-beta-lactam antibiotic that acts on bacterial cell wall synthesis, decreased the expression of penicillin-binding protein 3 and induced beta-lactamase. The antagonistic effect was reduced in the presence of high concentrations of the beta-lactamase inhibitor tazobactam or in fosfomycin-resistant mutants. We suggest that products resulting from fosfomycin cell wall damage could interact with a system that regulates penicillin-binding protein and beta-lactamase production.