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1.
Am J Rhinol Allergy ; 25(5): 369, 2011 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-29021069

RESUMEN

INTRODUCTION: To establish the efficacy of bepotastine besilate ophthalmic solution (bepotastine) 1.5%, a dual acting histamine H1 receptor antagonist approved for treatment of ocular itching associated with allergic conjunctivitis, compared to placebo in relieving ocular itching and redness for subjects with active allergic rhinoconjunctivitis. METHODS: A randomized, double-masked, placebo-controlled, confirmatory natural exposure study of bepotastine 1.5% and placebo was conducted during allergy season at 12 clinical sites throughout the U.S. Following a 7-day screening period, eligible subjects ≥12 years old were assigned in a 1:1 ratio to dosing OU b.i.d. either bepotastine 1.5% (n = 123) or placebo (n = 122). Subjects recorded instantaneous grades for their ocular symptoms prior to their next dose for 14 consecutive days. Clinically significant reduction in ocular sign or symptom grades between treatment groups required p ≤ 0.05 as determined by ANCOVA analysis. RESULTS: Significant clinical effectiveness with bepotastine 1.5% was demonstrated over the 2-week treatment period in comparison to placebo in the intent-to-treat population for reducing mean instantaneous grades for both ocular itching (p = 0.007) and redness (p = 0.001). Investigator rating of efficacy over the 2-week treatment period across response categories was also superior for bepotastine 1.5% compared to placebo (p = 0.024). Only one subject discontinued participation in the study due to an adverse event. CONCLUSIONS: These data support bepotastine 1.5% as an effective treatment for allergen-induced signs and symptoms in a clinical study designed to closely resemble the conditions under which patients with allergic rhinoconjunctivitis would require treatment.

3.
Can J Microbiol ; 47(5): 382-91, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11400727

RESUMEN

In the first part of this study, generation times relative to temperature, together with cardinal and conceptual temperatures, were determined for four strains of Xenorhabdus bacteria that represented three geographically distinct species. The data showed that the NF strain of Xenorhabdus bovienii, like the Umeå strain of the same species, is psychrotrophic, while Xenorhabdus sp. TX strain resembles Xenorhabdus nematophila All strain in being mesophilic. In the second part, the capacity of these bacteria to adapt to changes in temperature, shown by changes in fatty acid composition, was investigated. As temperature declined, the proportions of the two major unsaturated fatty acids, palmitoleic (16:1omega7) acid and oleic (18:1omega9) acid, increased significantly in all of the strains. The proportion of the prevalent saturated fatty acid, which was palmitic acid (16:0), decreased. In the All, NF, and Umeå strains, myristic acid (14:0), margaric acid (17:0), cyclopropane (17:0c), and arachidic acid (20:0) decreased with decreasing temperature. In the third part of the study, the synthesis of isozymes in response to changing temperature was investigated. For the seven enzymes studied, the numbers for which isozyme synthesis was temperature related were as follows: five for Umeå, four for All, three for NF, and two for TX. Where the study dealt with fatty acid composition and isozyme synthesis, the results show a broad capacity for physiological temperature adaptation among strains of different climatic origin.


Asunto(s)
Ácidos Grasos/análisis , Rabdítidos/microbiología , Simbiosis , Xenorhabdus/enzimología , Animales , Técnicas de Tipificación Bacteriana , Isoenzimas/análisis , Temperatura , Xenorhabdus/clasificación
4.
Can J Microbiol ; 46(7): 618-22, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10932355

RESUMEN

Two bacterial symbionts of entomopathogenic nematodes, one of which originated from Texas, U.S.A., and the other from Newfoundland, Canada, were characterized phenotypically. These strains belonged to the genus Xenorhabdus. The Newfoundland (NF) strain was shown to be X. bovienii but the Texas (TX) strain was not identified at the species level. Four additional cultures of Xenorhabdus were included in the study. These were a strain of X. bovienii (Umeå), which was from a nematode of European origin, and strains of X. nematophilus, X. beddingii, and X. poinarii. The tests used in this study indicated identical properties for the NF (North American) and Umeå (European) strains of X. bovienii. These could be differentiated from the other strains studied by their failure to grow at 34 degrees C and resistance to low concentrations of a mixture of amoxilline and clavulanic acid. The Xenorhabdus TX strain could be differentiated from the other strains studied by its failure to grow at 10 degrees C. Of the tests done, approximately 30 were useful in distinguishing between the strains and species studied.


Asunto(s)
Nematodos/microbiología , Simbiosis , Xenorhabdus/clasificación , Animales , Control de Insectos , Terranova y Labrador , Fenotipo , Texas
5.
Can J Microbiol ; 44(3): 251-8, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9643966

RESUMEN

Bacteria belonging to the family Vibrionaceae were suspended using saline and a solution prepared from a marine-cations supplement. The effect of this on the profile of oxidized substrates obtained when using Biolog GN MicroPlates was investigated. Thirty-nine species belonging to the genera Aeromonas, Listonella, Photobacterium, and Vibrio were studied. Of the strains studied, species of Listonella, Photobacterium, and Vibrio could be expected to benefit from a marine-cations supplement that contained Na+, K+, and Mg2+. Bacteria that are not of marine origin are usually suspended in normal saline. Of the 39 species examined, 9 were not included in the Biolog data base and were not identified. Of the 30 remaining species, 50% were identified correctly using either of the suspending solutions. A further 20% were correctly identified only when suspended in saline. Three species, or 10%, were correctly identified only after suspension in the marine-cations supplemented solution. The remaining 20% of species were not correctly identified by either method. Generally, more substrates were oxidized when the bacteria had been suspended in the more complex salts solution. Usually, when identifications were incorrect, the use of the marine-cations supplemented suspending solution had resulted in many more substrates being oxidized. Based on these results, it would be preferable to use saline to suspend the cells when using Biolog for identification of species of Vibrionaceae. A salts solution containing a marine-cations supplement would be preferable for environmental studies where the objective is to determine profiles of substrates that the bacteria have the potential to oxidize. If identifications are done using marine-cations supplemented suspending solution, it would be advisable to include reference cultures to determine the effect of the supplement. Of the Vibrio and Listonella species associated with human clinical specimens, 8 out of the 11 studied were identified correctly when either of the suspending solutions was used.


Asunto(s)
Técnicas de Tipificación Bacteriana , Cloruro de Magnesio/farmacología , Cloruro de Potasio/farmacología , Cloruro de Sodio/farmacología , Vibrionaceae/clasificación , Vibrionaceae/metabolismo , Aeromonas/clasificación , Aeromonas/metabolismo , Medios de Cultivo , Oxidación-Reducción , Photobacterium/clasificación , Photobacterium/metabolismo , Agua de Mar/microbiología , Vibrio/clasificación , Vibrio/metabolismo
6.
J Refract Surg ; 11(3 Suppl): S280-3, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7553108

RESUMEN

Radial keratotomy has been used for the treatment of myopia since 1979. Until recently, patients with undercorrected myopia had recourse only to repeated keratotomy. Now patients undercorrected after two or more radial keratotomy procedures can be treated with the excimer laser to reduce the residual myopia. Nineteen eyes of 17 patients with undercorrected myopia after repeated radial had excimer photoradial keratectomy performed. The mean residual spherical equivalent refractive error after radial keratotomy was -2.74 +/- 1.06 diopters (D). This was further reduced after PRK. Final uncorrected visual acuity ranged from 20/20 to 20/70. Excimer laser PRK offers a safe and more controlled method of treating residual after radial keratotomy.


Asunto(s)
Córnea/cirugía , Queratotomía Radial/efectos adversos , Miopía/cirugía , Queratectomía Fotorrefractiva , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Humanos , Láseres de Excímeros , Masculino , Persona de Mediana Edad , Miopía/etiología , Miopía/fisiopatología , Complicaciones Posoperatorias , Refracción Ocular , Reoperación , Agudeza Visual/fisiología
7.
Can J Microbiol ; 40(6): 446-55, 1994 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8050065

RESUMEN

Eighty regional strains of Vibrio isolated from the seasonally cold waters of coastal Newfoundland, and a number of Vibrio reference cultures, were studied. The regional strains had been isolated from the brown macroalga Alaria esculenta and the giant scallop Placopecten magellanicus and were known to grow at 4 degrees C. The strains were grouped according to their arginine-dihydrolase reactions and examined by numerical analysis. According to phenotypic properties the arginine-dihydrolase positive strains closely resembled Vibrio splendidus biovar I. Most clusters of the arginine-dihydrolase negative strains appeared to be unique but the closest phenotypic resemblance among some strains was with Vibrio ordalii. Some strains were examined using the random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR) technique for fingerprinting and it was shown that the regional strains were significantly different from either V. splendidus biovar I or V. ordalii. Generally, the strains from seaweed clustered separately from those that were from scallops. Strains in some clusters, especially those from the seaweed, were able to utilize most of the compounds that were tested as sole sources of carbon and energy.


Asunto(s)
Agua de Mar , Vibrio/clasificación , Microbiología del Agua , Animales , Técnicas de Tipificación Bacteriana , Secuencia de Bases , Frío , Dermatoglifia del ADN , ADN Bacteriano/análisis , Hidrolasas/metabolismo , Datos de Secuencia Molecular , Moluscos/microbiología , Terranova y Labrador , Phaeophyceae , Fenotipo , Reacción en Cadena de la Polimerasa , Vibrio/genética , Vibrio/aislamiento & purificación , Vibrio/fisiología
8.
Artículo en Inglés | MEDLINE | ID: mdl-8361987

RESUMEN

We compared the effect of different aspirin schedules, dosages, and formulations on various bleeding time parameters including bleeding time, plasma and total blood volume, and levels of the stable metabolites of thromboxane A2 (TXA2) and prostacyclin (PGI2) (respectively, TXB2 and 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha)) to determine the optimal dosage and formulation of aspirin to inhibit TXA2 production while sparing PGI2. In a randomized, parallel study, 52 healthy male volunteers (62 independent observations) with no history of bleeding disorders were given 80 mg or 325 mg of regular aspirin, or 325 mg of enteric-coated aspirin to ingest daily (14 pills) or every other day (7 pills) for a continuous 14 day period. Bleeding times were performed on day 1 before aspirin, 6 h after aspirin on day 1, and before aspirin on day 14. Bleeding times, plasma volume, and total volume increased significantly from before aspirin to after 6 h and 14 days (p < 0.0001 for all parameters) for all aspirin formulations. For day 1 before aspirin ingestion to 6 h later, both TX and PGI2 (p < 0.008) decreased significantly. 6 h after ingestion of aspirin on day 1 to day 14, both TX and PGI2 levels also significantly decreased (p < 0.0001). There was a highly significant decrease in PGI2 production on every other day aspirin schedules (p = 0.0001) particularly with 80 mg of aspirin, while the decrease in PGI2 production on daily aspirin was not significant (p = 0.10). The most favourable ratio of 6-keto-PGF1 alpha to TXB2 occurred with 80 mg daily.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Aspirina/administración & dosificación , Tiempo de Sangría , Eicosanoides/sangre , 6-Cetoprostaglandina F1 alfa/sangre , Adulto , Anciano , Aspirina/farmacología , Formas de Dosificación , Epoprostenol/sangre , Humanos , Masculino , Persona de Mediana Edad , Comprimidos Recubiertos/administración & dosificación , Comprimidos Recubiertos/farmacología , Tromboxano A2/sangre , Tromboxano B2/sangre
9.
Microbios ; 52(210): 39-49, 1987.
Artículo en Inglés | MEDLINE | ID: mdl-3121984

RESUMEN

The extraction of adenosine triphosphate (ATP) from six strains of bacteria, chosen for differences in cell-wall composition and habitat, was performed. The solvents were two in common use, Tris-ethylenediaminetetraacetate (Tris-EDTA) and trichloroacetic acid (TCA), and two promising, though less utilized solvents, dimethylsulphoxide (DMSO) and acetone. ATP was determined by the luciferin-luciferase reaction. Of the solvents used, DMSO and acetone were the most effective considering the different kinds of bacteria tested and, of these two, DMSO was the most convenient to use. Tris-EDTA was not as effective as the other solvents tested and TCA, which was effective with most strains, gave low yields when used with cultures grown in artificial seawater broth. Internal standards were used to determine if there were substances present that could inhibit the reaction of released ATP with the luciferin-luciferase reagent. Extracts of ATP, stored at -20 degrees C, were stable for up to 3 weeks.


Asunto(s)
Acetona , Adenosina Trifosfato/análisis , Bacterias/análisis , Dimetilsulfóxido , Solventes , Bacillus megaterium/análisis , Ácido Edético , Luciferina de Luciérnaga , Luciferasas , Pseudomonas/análisis , Pseudomonas fluorescens/análisis , Salmonella typhimurium/análisis , Staphylococcus/análisis , Ácido Tricloroacético , Trometamina
10.
Appl Environ Microbiol ; 47(1): 213-5, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6696419

RESUMEN

Optimal incubation times and temperatures were determined for populations of psychrophilic and psychrotrophic bacteria from a seasonally cold ocean. The application of conventional pragmatic criteria did not differentiate the two populations, although they could be distinguished by growth at two temperatures.


Asunto(s)
Bacterias/crecimiento & desarrollo , Frío , Microbiología del Agua , Agua de Mar
11.
Can J Microbiol ; 27(3): 350-7, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7237281

RESUMEN

Studies of the marine bacterium Alteromonas haloplanktis 214 (formerly referred to as marine pseudomonad B-16) showed that as the Na+ concentration in the growth medium decreased from 230 to 34 mM, the lowest concentration permitting growth, the length of the lag period preceding exponential growth increased. Once growth had begun, except for a slight reduction in rate of growth at 34 mM Na+, the generation time and extent of growth remained essentially constant over the range of Na+ concentrations tested. Plate counts showed that during the lag period the numbers of viable cells introduced as inoculum into a complex medium containing 33 mM Na+ decreased exponentially before increasing. Repeated subculture of the cells at 33 mM Na+ failed to eliminate the lag period or reduce the loss of viability of the cells. The viability loss and the lag period could be eliminated either by raising the NaCl concentration to 130 mM or by adding sufficient sucrose to make the osmotic pressure of the medium equal to that obtained by adding 130 mM NaCl. In a chemically defined medium, sucrose added to maintain tonicity reduced but did not eliminate the lag periods obtained at suboptimal Na+ concentrations. Increasing the number of cells plated on trypticase agar medium reduced the Na+ concentration required to permit growth. Evidence was obtained of a requirement of A. haloplanktis for Ca2+ for growth. Ca2+ spared to a small extent the requirement for Na+ for growth. Some 10(10) cells of a histidine-requiring, streptomycin-resistant mutant of A. haloplanktis 214, still viable after treatment with N-methyl-N'-nitro-N-nitrosoguanidine, were screened for capacity to grow in the absence of Na+. Since no non-Na+-requiring mutants were isolated, the requirement of this organism for Na+ would appear to be extremely stable.


Asunto(s)
Pseudomonadaceae/crecimiento & desarrollo , Sodio/metabolismo , Microbiología del Agua , Calcio/metabolismo , Metilnitronitrosoguanidina , Mutación , Pseudomonadaceae/genética , Pseudomonadaceae/metabolismo , Agua de Mar
12.
Can J Microbiol ; 27(3): 358-63, 1981 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7237282

RESUMEN

Cells of a histidine-auxotrophic, streptomycin-resistant mutant of marine bacterium Alteromonas haloplanktis 214 were grown at or near the lowest concentration of Na+ permitting growth (30-33 mM Na+). When suspended in solutions containing 10 mMKCl and either 30, 100, or 300 mM NaCl, the intracellular to extracellular K+ ratios were similar to those obtained with cells of the parent organism grown at more nearly optimum Na+ concentrations, whereas the Na+ ratios were somewhat larger. Cells of the parent organism grown at 32 mM Na+ transported alpha-aminoisobutyric acid (AIB) at only one-third the rate and to less than one-quarter of the extent of cells grown at 130 mM Na+ even when the NaCl concentration during transport was raised to optimum levels. The Km for uptake of AIB by cells grown at 32 and 130 mM Na+ was the same but the Vmax was higher for cells grown at 130 mM. The Vmax for cells grown at both concentrations of Na+ increased as the Na+ concentration in the uptake medium increased. It was concluded that none of the observations made could account for the fact that both parent and mutant of A. haloplanktis grow at 30-32 mM Na+ only after a very long lag period, and then grow at near normal rates once logarithmic growth begins despite the fact that the osmotic pressure of the medium is very low.


Asunto(s)
Ácidos Aminoisobutíricos/metabolismo , Pseudomonadaceae/crecimiento & desarrollo , Sodio/metabolismo , Microbiología del Agua , Transporte Biológico Activo , Mutación , Potasio/metabolismo , Pseudomonadaceae/genética , Pseudomonadaceae/metabolismo , Agua de Mar
13.
Can J Microbiol ; 26(2): 107-14, 1980 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7407699

RESUMEN

Differential centrifugation of stationary phase broth culture of Rhizobium japonicum yielded two distinct morphological types of bacterial cells, rods, and small coccoid forms with capsulated and non-capsulated cells in each group. The rods usually had polar capsules which resulted in "star" formation. The coccoid bacteria were either free with thick capsular material surrounding the cells or held together in a common capsular sheath forming clusters and chains. 125I soybean. lectin bound to the two types of cells. The binding sites were localized in the capsular material as revealed by colloidal gold- and ferritin-labelled lectin. Both fractions were capable of nodule formation in the soybean.


Asunto(s)
Rhizobium/citología , Lectinas/metabolismo , Rhizobium/aislamiento & purificación , Rhizobium/metabolismo
14.
Appl Environ Microbiol ; 37(5): 836-40, 1979 May.
Artículo en Inglés | MEDLINE | ID: mdl-384899

RESUMEN

Two variations of the multiple-tube fermentation technique were used to enumerate fecal coliforms in commercially processed, frozen crab meat. These were the EC confirmation test and a more rapid method that requires medium A-1. The method with medium A-1 was more specific than the EC confirmation test for detecting Escherichia coli type 1. E. coli was isolated from 84% of the positive medium A-1 tubes, whereas it was isolated from only 64% of the positive tubes of EC broth. When samples of crab meat were inoculated with known amounts of E. coli, better estimates of the known numbers were obtained by the medium A-1 method. Several species of nonfecal coliforms were isolated from cultures in EC broth. These belonged to the genera Klebsiella, Citrobacter, Enterobacter, and Serratia. Apparently these strains were naturally adapted to growth at an elevated temperature because the majority were able to grow at 44.5 degrees C when retested in EC broth. Fewer species of nonfecal coliforms were isolated from medium A-1. Those that were isolated belonged to the genera Citrobacter and Enterobacter.


Asunto(s)
Braquiuros , Medios de Cultivo , Escherichia coli/aislamiento & purificación , Microbiología de Alimentos , Enterobacteriaceae/aislamiento & purificación , Alimentos Congelados
15.
Microbios ; 15(61-62): 209-19, 1976.
Artículo en Inglés | MEDLINE | ID: mdl-189162

RESUMEN

Bordetella pertussis strain number 18334 was grown in media which yielded cells with either a normal complement of surface antigens (X-model), or cells which were phenotypically altered (C-model). Neither X- nor C-mode bacteria incorporated more than traces of radioactivity when exposed to Na 125 I, lactoperoxidase and a source of H2O2 under conditions which gave substantial labelling of BSA and other soluble proteins. In contrast, envelope preparations were readily labelled. Analysis by sodium dodecyl sulphate-polyacrylamide gel electrophoresis showed that several polypeptides had incorporated 125 I but not in amounts proportional to their abundance in the envelopes. Envelopes from C-mode cells gave a labelling pattern similar to those of X-mode except in one region. Control experiments suggested that the failure of intact cells to become labelled may be due to bacterial inhibition of the reagents.


Asunto(s)
Proteínas Bacterianas/aislamiento & purificación , Bordetella pertussis/análisis , Autorradiografía/métodos , Proteínas Bacterianas/análisis , Pared Celular/análisis , Radioisótopos de Yodo , Lactoperoxidasa , Peso Molecular , Péptidos/análisis
19.
J Bacteriol ; 97(3): 1026-32, 1969 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-4975743

RESUMEN

Purification of beta-hemolysin was achieved by ammonium sulfate precipitation, Sephadex G-100 gel filtration, carboxymethyl cellulose column chromatography, and density gradient electrophoresis. Active fractions eluted from carboxymethyl cellulose contained at least one nonhemolytic protein, and omission of this step was not detrimental to the purification process. Density gradient electrophoresis yielded approximately 1.6 mg of highly active purified beta-hemolysin per liter of culture supernatant liquid. Purified beta-hemolysin gave a single line on gel double diffusion and immunoelectrophoresis. A single symmetrical peak formed in the analytical ultracentrifuge, and the sedimentation coefficient was calculated to be 1.7S. The purified beta-hemolysin was stable at 4 C and could be lyophilized. Magnesium cations were required for full expression of beta-hemolytic activity. beta-Hemolysin was lethal for rabbits when injected intravenously in amounts between 40 and 160 mug. Crude beta-hemolysin was more stable than purified beta-hemolysin when heated at 60 C for 30 min. Purified beta-hemolysin lost almost all of its activity on subsequent heating at 100 C for 10 min.


Asunto(s)
Proteínas Hemolisinas , Staphylococcus , Animales , Centrifugación por Gradiente de Densidad , Precipitación Química , Cromatografía , Cromatografía en Gel , Electroforesis , Proteínas Hemolisinas/análisis , Proteínas Hemolisinas/aislamiento & purificación , Proteínas Hemolisinas/toxicidad , Calor , Inmunodifusión , Inmunoelectroforesis , Conejos
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