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1.
Appl Microbiol Biotechnol ; 97(14): 6263-9, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23129183

RESUMEN

Laccases produced by white rot fungi have been extensively evaluated for their potential to decolorize textile wastewaters which contain salts like sodium chloride and sodium sulfate. The effect of sodium chloride and sodium sulfate on Trametes versicolor laccase during the decolorization of an anthraquinone dye (Reactive Blue 19) and the oxidation of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were evaluated by steady-state kinetic analysis. The results showed that, while sodium sulfate did not affect laccase activity, sodium chloride inhibited both ABTS oxidation and dye decolorization. However, the type of inhibition was substrate-dependent: it was hyperbolic, noncompetitive with ABTS and parabolic, noncompetitive with Reactive Blue 19. Furthermore, the results suggested that two chlorides may bind to laccase in the presence of the dye unlike recent inhibition models which suggest that there is only one inhibition site. This investigation is the first to provide evidence for and to propose a two-site model of laccase inhibition, providing new insight into NaCl inhibition of laccase. The proposed model is also useful to predict decolorization rates in the presence of sodium chloride and to determine operating conditions that will minimize inhibition.


Asunto(s)
Antraquinonas/metabolismo , Benzotiazoles/química , Colorantes/metabolismo , Inhibidores Enzimáticos/química , Proteínas Fúngicas/metabolismo , Lacasa/metabolismo , Cloruro de Sodio/química , Ácidos Sulfónicos/química , Trametes/enzimología , Antraquinonas/química , Biodegradación Ambiental , Colorantes/química , Proteínas Fúngicas/antagonistas & inhibidores , Proteínas Fúngicas/química , Cinética , Lacasa/antagonistas & inhibidores , Lacasa/química , Oxidación-Reducción
2.
Vaccine ; 41(48): 7250-7258, 2023 11 22.
Artículo en Inglés | MEDLINE | ID: mdl-37903680

RESUMEN

OBJECTIVES: We evaluated the frequency of moderate and severe adverse events following coadministration of seasonal influenza vaccine (SIV) versus placebo with COVID-19 vaccines among adults to support practice guidelines. METHODS: FluVID is a participant-blinded, phase IV, randomised control trial. On the same day as the participant's scheduled COVID-19 vaccine, participants were randomised to receive SIV or saline placebo; those assigned placebo at visit one then received SIV a week later, and vice versa. Self-reported adverse events were collected daily for seven days following each visit. The primary endpoint was any solicited adverse event of at least moderate severity occurring up to seven days following receipt of SIV or placebo. This was modelled using a Bayesian logistic regression model. Analyses were performed by COVID-19 vaccine type and dose number. RESULTS: Overall, 248 participants were enrolled; of these, 195 had received BNT162b2 and 53 had received mRNA1273 COVID-19 vaccines according to national guidelines. After randomisation, 119 were assigned to receive SIV and 129 were assigned to receive placebo at visit one. Adverse events were most frequently reported as mild (grade 1) in nature. Among 142 BNT162b2 booster dose one and 43 BNT162b2 booster dose two recipients, the posterior median risk difference for moderate/severe adverse events following SIV versus placebo was 13% (95% credible interval [CrI] -0.03 to 0.27) and 13% (95%CrI -0.37 to 0.12), respectively. Among 18 mRNA1273 booster dose one and 35 mRNA1273 booster dose two recipients, the posterior median risk difference of moderate/severe adverse events following influenza vaccine versus placebo was 6% (95%CrI -0.29 to 0.41) and -4% (95%CrI -0.30 to 0.23), respectively. CONCLUSION: Adverse events following SIV and COVID-19 co-administration were generally mild and occurred with similar frequency to events following COVID-19 vaccine alone. We found no evidence to justify routine separation of SIV and COVID-19 vaccine doses. CLINICAL TRIAL REGISTRATION: ACTRN12621001063808.


Asunto(s)
COVID-19 , Vacunas contra la Influenza , Gripe Humana , Adulto , Humanos , Vacunas contra la COVID-19/efectos adversos , Gripe Humana/prevención & control , COVID-19/prevención & control , Vacuna BNT162 , Teorema de Bayes , Estaciones del Año , Método Doble Ciego
3.
Biodegradation ; 20(4): 551-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19132327

RESUMEN

Although aerobic degradation of ethylene glycol is well documented, only anaerobic biodegradation via methanogenesis or fermentation has been clearly shown. Enhanced ethylene glycol degradation has been demonstrated by microorganisms in the rhizosphere of shallow-rooted plants such as alfalfa and grasses where conditions may be aerobic, but has not been demonstrated in the deeper rhizosphere of poplar or willow trees where conditions are more likely to be anaerobic. This study evaluated ethylene glycol degradation under nitrate-, and sulphate-reducing conditions by microorganisms from the rhizosphere of poplar and willow trees planted in the path of a groundwater plume containing up to 1.9 mol l(-1) (120 g l(-1)) ethylene glycol and, the effect of fertilizer addition when nitrate or sulphate was provided as a terminal electron acceptor (TEA). Microorganisms in these rhizosphere soils degraded ethylene glycol using nitrate or sulphate as TEAs at close to the theoretical stoichiometric amounts required for mineralization. Although the added nitrate or sulphate was primarily used as TEA, TEAs naturally present in the soil or CO(2) produced from ethylene glycol degradation were also used, demonstrating multiple TEA usage. Anaerobic degradation produced acetaldehyde, less acetic acid, and more ethanol than under aerobic conditions. Although aerobic degradation rates were faster, close to 100% disappearance was eventually achieved anaerobically. Degradation rates under nitrate-reducing conditions were enhanced upon fertilizer addition to achieve rates similar to aerobic degradation with up to 19.3 mmol (1.20 g) of ethylene glycol degradation l(-1) day(-1) in poplar soils. This is the first study to demonstrate that microorganisms in the rhizosphere of deep rooted trees like willow and poplar can anaerobically degrade ethylene glycol. Since anaerobic biodegradation may significantly contribute to the phytoremediation of ethylene glycol in the deeper subsurface, the need for "pump and treat" or an aerobic treatment would be eliminated, hence reducing the cost of treatment.


Asunto(s)
Glicol de Etileno/metabolismo , Populus/metabolismo , Salix/metabolismo , Anaerobiosis , Cromatografía de Gases , Fertilizantes , Populus/microbiología , Salix/microbiología
4.
Chemosphere ; 61(7): 956-64, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-15878190

RESUMEN

Alginate-immobilized Trametes versicolor decolorized Amaranth at similar rates in repeated batch culture when the dye was present in either (i) modified Kirk's medium containing 0.22 gl(-1) ammonium tartrate, (ii) the same buffer, thiamine, trace elements and glucose concentrations as in the modified Kirk's medium, or (iii) glucose alone at either 1, 5 or 10 gl(-1). With glucose alone (0.5 gl(-1)), Amaranth, Reactive Black 5, Reactive Blue 19 and Direct Black 22 had first-order decoloration rate constants of 0.56, 0.76, 0.52, and 0.15 h(-1), respectively. Mixtures of these dyes were also completely decolorized. After four successive decolorations, beads were kept in storage solutions for 48 d at 6 degrees C. CaCl2 (1g l(-1)) was the best storage solution as the beads were easier to handle and had the fastest decoloration rates after storage. Decoloration rates were faster with lower viscosity (less than 2000 cps) alginates and with softer beads which had a lower resistance to compression. Fungal colonization of the beads resulted in higher biomass concentrations with a corresponding higher decoloration rate but the beads became larger, had a lower resistance to compression and a higher percentage of bead breakage in a stirred tank reactor. Biomass, recovered from beads in which there was no growth, could be dispersed while the biomass from colonized beads formed a hollow, spherical shell due to growth on and near the bead surface and no growth in the bead interior. If alginate-immobilized T. versicolor is to be used in a stirred tank reactor, a high biomass loading during the immobilization phase and no fungal growth in the beads is recommended to have high decoloration rates and low bead breakage.


Asunto(s)
Alginatos , Basidiomycota/metabolismo , Colorantes/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Purificación del Agua/métodos , Biomasa , Células Inmovilizadas , Color , Colorantes/metabolismo , Medios de Cultivo , Ácido Glucurónico , Ácidos Hexurónicos , Textiles , Contaminantes Químicos del Agua/metabolismo
5.
J Invest Dermatol ; 105(1): 22-6, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7615970

RESUMEN

Although the Breslow measurement of tumor thickness of melanoma is the most significant predictor of survival, the biologic behavior of thick lesions remains unpredictable. MIB-1, a monoclonal antibody to a Ki-67 epitope, recognizes all proliferating cells. Unlike Ki-67 antibody, which requires frozen tissue, MIB-1 can be used on formalin-fixed tissue. Proliferation, measured by MIB-1 expression and mitotic index, was assessed as a prognostic factor in a group of patients with clinical stage I thick cutaneous melanoma (tumor thickness 4 mm or greater), for which predicted survival is low. From a melanoma data base, 97 patients with this type of melanoma were identified. Of these, 64 had lesional tissue available for study. The median follow-up time was 3.8 years (range 0.42-13.6 years). The percentage of MIB-1 reactivity was scored as low at less than 10% (n = 33), intermediate at 10% to 20% (n = 17), and high at greater than 20% (n = 14). Melanomas with high MIB-1 reactivity were associated with significantly poorer cause-specific survival compared with tumors with intermediate (p < 0.0001) or low MIB-1 reactivity (p = 0.0025). Multivariate analysis demonstrated that MIB-1 reactivity was a significant independent prognostic factor related to cause-specific survival (p = 0.0002) and was more sensitive than tumor thickness or mitotic index in this select group of high-risk patients. Identification of individuals with stage I thick cutaneous melanoma who are at risk of recurrent disease may improve patient management as new therapeutic modalities become available.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Melanoma/patología , Proteínas de Neoplasias/análisis , Proteínas Nucleares/análisis , Neoplasias Cutáneas/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Inmunohistoquímica , Antígeno Ki-67 , Masculino , Melanoma/mortalidad , Persona de Mediana Edad , Pronóstico , Neoplasias Cutáneas/mortalidad , Tasa de Supervivencia
6.
Am J Surg Pathol ; 11(6): 480-6, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3592062

RESUMEN

A case of bilateral adrenal pheochromocytomas with unusual morphologic features is reported in a 27-year-old man with a family history of von Hippel-Lindau disease. In both glands, the medulla was replaced by neoplasms with two distinct gross and microscopic appearances. There was typical pheochromocytoma in areas of dusky red tissue. The yellow nodules noted on gross examination were microscopically composed of large cells with vacuolated cytoplasm. Fat stains confirmed the presence of lipid in these areas. Immunohistochemistry revealed positivity for neuron-specific enolase and chromogranin in the cytoplasm of pheochromocytes, as well as in the perinuclear cytoplasm and processes of cells scattered in the yellow nodules. Ultrastructural examination of the yellow lesions showed characteristics of pheochromocytoma and an extensive accumulation of lipid. Although gross and light-microscopic examination of the yellow tissue suggested adrenal cortical nodules, immunohistochemistry and electon microscopy elucidated lipid degeneration within pheochromocytoma, a finding not previously described.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/patología , Neoplasias de las Glándulas Suprarrenales/patología , Metabolismo de los Lípidos , Feocromocitoma/patología , Neoplasias de la Corteza Suprarrenal/metabolismo , Neoplasias de las Glándulas Suprarrenales/metabolismo , Adulto , Diagnóstico Diferencial , Humanos , Masculino , Feocromocitoma/metabolismo
7.
Am J Med Genet ; 77(4): 306-9, 1998 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-9600741

RESUMEN

Ring X chromosomes that do not undergo inactivation may cause malformations and mental retardation. We report on a fetus with anencephaly, total dorsal rachischisis, and diaphragmatic hernia that was found to have a mosaic 45,X/46,X,r(X)(p11.22q12) karyotype. Fluorescent in situ hybridization (FISH) confirmed that the ring chromosome was X-derived. This report expands the phenotypic spectrum of mosaic monosomy X and small ring X chromosomes.


Asunto(s)
Anomalías Múltiples/genética , Aberraciones Cromosómicas , Trastornos de los Cromosomas , Feto/anomalías , Mosaicismo , Cromosoma X , Anomalías Múltiples/embriología , Anomalías Múltiples/patología , Humanos , Cromosomas en Anillo
8.
Med Sci Sports Exerc ; 22(5): 605-14, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-2233199

RESUMEN

Possible changes in muscle size and function due to resistance training were examined in prepubertal boys. Thirteen boys (9-11 yr) volunteered for each of the training and control groups. Progressive resistance training was performed three times weekly for 20 wk. Measurements consisted of the following: 1 repetition maximum (RM) bench press and leg press; maximal voluntary isometric and isokinetic elbow flexion and knee extension strength; evoked isometric contractile properties of the right elbow flexors and knee extensors; muscle cross-sectional area (CSA) by computerized tomography at the mid-right upper arm and thigh; and motor unit activation (MUA) by the interpolated twitch procedure. Training significantly increased 1 RM bench press (35%) and leg press (22%), isometric elbow flexion (37%) and knee extension strength (25% and 13% at 90 degrees and 120 degrees, respectively), isokinetic elbow flexion (26%) and knee extension (21%) strength, and evoked twitch torque of the elbow flexors (30%) and knee extensors (30%). There were no significant effects of training on the time-related contractile properties (time to peak torque, half-relaxation time), CSA, or %MUA of the elbow flexors or knee extensors. There was, however, a trend toward increased MUA for the elbow flexors and knee extensors in the trained group. Strength gains were independent of changes in muscle CSA, and the increases in twitch torque suggest possible adaptations in muscle excitation-contraction coupling. Improved motor skill coordination (especially during the early phase of training), a tendency toward increased MUA, and other undetermined neurological adaptations, including better coordination of the involved muscle groups, are likely the major determinants of the strength gains in this study.


Asunto(s)
Músculos/fisiología , Resistencia Física/fisiología , Esfuerzo Físico , Antropometría , Fenómenos Biomecánicos , Composición Corporal , Niño , Potenciales Evocados , Humanos , Contracción Isométrica , Masculino , Músculos/anatomía & histología , Educación y Entrenamiento Físico , Tomografía Computarizada por Rayos X
9.
Ultrasound Med Biol ; 22(7): 845-53, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8923704

RESUMEN

The incidence and mortality rate of cutaneous melanoma continue to increase throughout the world, making the study of melanoma biology an important area of current research. While recent breakthroughs in transgenic mouse technology have led to promising mouse skin models of melanoma, there is presently no technique available for quantitatively studying subsurface melanoma progression, in vivo. We demonstrate the first application of an imaging method called ultrasound backscatter microscopy (UBM) for imaging early murine melanomas with spatial resolution of 30 microns axial and 60 microns lateral. Murine B16 F10 melanomas have been imaged from their earliest detection, over several days, until they are 2 to 5 mm in diameter. Melanoma dimensions measured by UBM were found to be in excellent agreement with those determined histopathologically on the excised tumours. The relative rms errors in UBM-determined melanoma height and width were found to be 8.7% and 4.2%, respectively. The mean rate of increase in tumour height of early murine melanoma was found to be 0.37 +/- 0.06 mm/day. Computer-generated volumetric renderings of melanomas have been produced from three-dimensional image data, allowing quantitative comparisons of tumour volumes to be made. Using a priori assumptions of ellipsoid tumour shape, the relative error in UBM-determined volume was shown to be less than 17%. These results should be of considerable interest to investigators studying melanoma biology using mouse skin models, and have implications in the use of high frequency ultrasound imaging for the clinical assessment of cutaneous melanoma.


Asunto(s)
Melanoma Experimental/diagnóstico por imagen , Neoplasias Cutáneas/diagnóstico por imagen , Animales , Procesamiento de Imagen Asistido por Computador , Melanoma Experimental/patología , Ratones , Ratones Endogámicos C57BL , Microscopía , Procesamiento de Señales Asistido por Computador , Neoplasias Cutáneas/patología , Ultrasonografía/métodos
10.
J Pediatr Surg ; 33(6): 893-5, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9660223

RESUMEN

Although mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland neoplasm in childhood and adolescence, it is rarely found in children under the age of 10. A 6-year-old girl had an asymptomatic neck mass for 5 months. Clinical examination findings showed a 1.5-cm smooth and firm but mobile nontender mass located in the upper left anterior cervical triangle, clinically separate from the parotid gland. Ultrasound examination findings showed a vascular mass, with a cystic component, possibly within the tail of the parotid gland. An excisional biopsy was performed and frozen section showed a low-grade MEC. A left superficial parotidectomy was then performed. Final histopathologic examination showed one positive resection margin. Subsequently, reexcision of the surgical site and an upper modified neck dissection was undertaken. This unusual presentation of MEC as a neck mass in one of the youngest reported patients illustrates that the anatomic region for parotid tumors is large. Possibly some of these tumors may arise from heterotopic or accessory parotid tissue.


Asunto(s)
Carcinoma Mucoepidermoide/diagnóstico , Neoplasias de la Parótida/diagnóstico , Carcinoma Mucoepidermoide/patología , Carcinoma Mucoepidermoide/cirugía , Niño , Femenino , Humanos , Neoplasias de la Parótida/patología , Neoplasias de la Parótida/cirugía
11.
Bioresour Technol ; 101(7): 2230-5, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20015643

RESUMEN

The decolorization and detoxification of textile dyes by fungal laccase immobilized on porous glass beads were evaluated. Anthraquinone (Reactive blue 19 and Dispersed blue 3) and indigoid (Acid blue 74) dyes were degraded more rapidly than the azo dyes (Acid red 27 and Reactive black 5). There was no dye sorption to the enzyme bed when decolorization rates were high (>12 microM dye/U-h) but at moderate rates (8 to>0.06 microM/U-h), there was a transient color which disappeared upon prolonged exposure. With Reactive black 5, permanent adsorption occurred most likely because laccase had been totally inactivated. Although laccase treatment was more efficient at decolorizing the anthraquinone dyes, their toxicity (as determined by the Microtox assay) increased while the less efficiently decolorized solutions of azo and indigoid dyes became less toxic. These results demonstrate the potential and limitations of using immobilized laccase to enzymatically decolorize a range of different dye classes and reduce dye toxicity in a single step.


Asunto(s)
Colorantes/metabolismo , Enzimas Inmovilizadas/metabolismo , Vidrio/química , Lacasa/metabolismo , Microesferas , Trametes/enzimología , Absorción/efectos de los fármacos , Biodegradación Ambiental/efectos de los fármacos , Color , Colorantes/química , Colorantes/toxicidad , Inactivación Metabólica , Porosidad/efectos de los fármacos , Trametes/efectos de los fármacos
12.
Appl Microbiol Biotechnol ; 77(4): 819-23, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17917725

RESUMEN

Laccase (31.5 U of activity/g or 4.39 mug of protein/m(2)) from Trametes versicolor was immobilized on controlled-porosity-carrier silica beads and evaluated for the decolouration of Reactive blue 19, an anthraquinone dye. Although there was an initial, rapid adsorption of the dye to the packed bed in a recirculating reactor, about 97.5% of Reactive blue 19 removal was due to enzymatic degradation. The free enzyme lost 52% of its activity in 48 h. However, the activity of the immobilized laccase was unchanged after 4 months of storage in phosphate buffer under ambient conditions followed by three successive decolourations over 120 h. Treating the laccase immobilized beads with ethanolamine reduced dye adsorption by 40%.


Asunto(s)
Antraquinonas/aislamiento & purificación , Basidiomycota/enzimología , Enzimas Inmovilizadas/química , Microbiología Industrial , Lacasa/metabolismo , Antraquinonas/metabolismo , Color , Lacasa/biosíntesis , Dióxido de Silicio/química
14.
Philos Trans R Soc Lond B Biol Sci ; 274(932): 203-26, 1976 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-8799

RESUMEN

In the so-called "cryptonephric" condition of the excretory system in insects the distal ends of the Malpighian tubules are closely applied to the rectum and enclosed with it in a special chamber, the perinephric space, separated from the rest of the body cavity by the perinephric membrane. The term "rectal complex" refers to this association of tubules and rectum, which is found in the larvae (but not in the adults) of most Lepidoptera. In the mealworm (Coleoptera) the rectal complex has notable ability to remove water from the faeces, but this ability is not conspicuously developed in the larvae of the two species of Lepidoptera here studied: Pieris brassicae and Manduca sexta. On the other hand these larvae have notable ability to maintain salt balance under heavy dietary loading, and in this the rectal complex plays an important part. A study of salt balance in more detail has shown that more sodium can be eliminated in the faeces than enters the rectal complex from the intestine. Consideration of other possible routes of entry points strongly to the Malpighian tubules. Superimposed upon a new flow of tubule fluid out of the rectal complex there is a tidal flow, brought about by the rectal musculature and amplified by dilatations of the cryptonephric tubules, which could bring in fluid from the free tubules and afford opportunity for the uptake of salts. Evidence is presented in support of this view. This tidal flow of tubule fluid and uptake of salts could be the basis of the build-up of high osmolarity in the perinephric fluid and could contribute to the removal of water from the faeces. It could also be the basic mechanism in the mealworm, the leptophragmal mechanism being superimposed upon it.


Asunto(s)
Lepidópteros/fisiología , Animales , Cloruros/metabolismo , Larva , Lepidópteros/anatomía & histología , Túbulos de Malpighi/anatomía & histología , Túbulos de Malpighi/metabolismo , Túbulos de Malpighi/fisiología , Potasio/metabolismo , Recto/anatomía & histología , Recto/metabolismo , Recto/fisiología , Sodio/metabolismo , Agua/metabolismo , Equilibrio Hidroelectrolítico
15.
Med Care ; 20(6): 615-22, 1982 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-7109744

RESUMEN

Patients have the option to participate in many investigations of non-compliance for medical recommendations. The question can therefore be raised about whether a tendency to volunteer for medical research is consistent with a tendency to comply with other medical treatment requests. In short, are volunteers or participants generally compliant relative to nonparticipants? This study examined past compliance for recommended follow-up appointments in patients who were requested to participate in a blood pressure assessment program and in a subsequent study on compliance for hypertensive regimens. Hospital records of the patients were reviewed for the two-year period that preceded the request to participate. Analysis of variance demonstrated significant differences in past compliance for participants and nonparticipants. The results of this study suggest that investigations of noncompliance have used samples that are select for compliant behavior. The implications of this study on compliance research are discussed.


Asunto(s)
Servicio Ambulatorio en Hospital/estadística & datos numéricos , Cooperación del Paciente , Muestreo , Adulto , Citas y Horarios , Etnicidad , Femenino , Humanos , Hipertensión/terapia , Masculino , Manitoba , Persona de Mediana Edad , Proyectos de Investigación , Factores Socioeconómicos
16.
Appl Environ Microbiol ; 69(9): 5255-62, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12957911

RESUMEN

An enrichment culture capable of naphthalene mineralization reduced Fe(III) oxides without direct contact in anaerobic soil microcosms when the Fe(III) was placed in dialysis membranes or entrapped within alginate beads. Both techniques demonstrated that a component in soil, possibly humic materials, facilitated Fe(III) reduction when direct contact between cells and Fe(III) was not possible. The addition of the synthetic Fe(III) chelator, nitrilotriacetic acid (NTA), to soil enhanced Fe(III) reduction across the dialysis membrane and alginate beads, with the medium changing from clear to a dark brown color. An NTA-soil extract was more effective in Fe(III) reduction than the extracted soil itself. Characteristics of the NTA extract were consistent with that of humic substances. The results indicate that NTA improved Fe(III) reduction not by Fe(III) solubilization but by extraction of humic substances from soil into the aqueous medium. This is the first study in which stimulation of Fe(III) reduction through the addition of chemical chelators is shown to be due to the extraction of electron-shuttling compounds from the soil and not to solubilization of the Fe(III) and indicates that mobilization of humic materials could be an important component of anaerobic biostimulation.


Asunto(s)
Bacterias Anaerobias/metabolismo , Compuestos Férricos/metabolismo , Ácido Nitrilotriacético/farmacología , Microbiología del Suelo , Anaerobiosis , Bacterias Anaerobias/efectos de los fármacos , Bacterias Anaerobias/crecimiento & desarrollo , Sustancias Húmicas , Cinética , Oxidación-Reducción , Factores de Tiempo
17.
Appl Environ Microbiol ; 55(3): 584-9, 1989 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16347867

RESUMEN

The possibility of using the nutritionally versatile bacterium Pseudomonas cepacia to produce poly-beta-hydroxyalkanoic acid was evaluated. Chemostat culture showed that growth of P. cepacia became nitrogen limited when the molar carbon-to-nitrogen ratio of the medium fed into the fermentor was above 15. When grown under nitrogen limitation in batch culture with fructose as the sole source of carbon, P. cepacia accumulated poly-beta-hydroxybutyric acid (PHB) in excess of 50% of the dry weight of its biomass. In batch culture, almost no PHB was produced until the onset of nitrogen limitation. After this point, PHB was produced at a linear rate of 0.12 g liter h (from a constant value of 1.6 g of cellular protein liter). PHB produced by P. cepacia had a weight-average molecular weight of 5.37 x 10 g mol and a polydispersivity index of 3.9. Poly(beta-hydroxybutyric acid-beta-hydroxyvaleric acid) copolymer was produced with a poly-beta-hydroxybutyric acid-poly-beta-hydroxyvaleric acid ratio of up to 30% by weight when propionic acid was added to the medium.

18.
Can J Surg ; 39(1): 53-6, 1996 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8599793

RESUMEN

A 38-year-old woman with stage T4N0M0 adenocarcinoma of the cecum presented with what seemed to be an appendiceal abscess. She had a 10-month history of intermittent abdominal pain in the right lower quadrant. Initial laparotomy revealed an abscess in that quadrant. The abscess was drained. A mass in the cecum, associated with dense fibrous tissue and abscess formation, was found on subsequent surgical exploration. Pathological examination revealed a well-differentiated mucinous adenocarcinoma of the cecum with transmural invasion. The lesion had replaced most of the vermiform appendix and was associated with a periappendiceal abscess. Colonic carcinoma masquerading as acute appendicitis or an appendiceal abscess is a well-recognized entity in the elderly but may be overlooked in younger patients because malignant disease is not suspected.


Asunto(s)
Absceso/etiología , Adenocarcinoma Mucinoso/diagnóstico , Apéndice , Neoplasias del Ciego/diagnóstico , Adenocarcinoma Mucinoso/patología , Adenocarcinoma Mucinoso/cirugía , Adulto , Enfermedades del Ciego/etiología , Neoplasias del Ciego/patología , Neoplasias del Ciego/cirugía , Femenino , Humanos
19.
Mod Pathol ; 8(2): 150-4, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7777475

RESUMEN

Since the discovery of bcl-2 proto-oncogene in follicular lymphomas, the protein product has been detected in a variety of normal tissues including skin, where it is expressed in basal keratinocytes. Recent studies indicate that bcl-2 protein is detected in nonlymphoid malignancies such as neuroblastoma and carcinomas of the lung and prostate. This study investigates the presence of bcl-2 protein in benign and malignant melanocytic neoplasms of the skin. Immunohistochemical analysis of bcl-2 protein expression was performed on 39 nevi and 60 malignant melanomas, including 21 metastases. There was diffuse strong immunopositivity for bcl-2 protein in 100% of nevi and 65% (43/60) of primary and metastatic melanomas. bcl-2 protein was diffusely expressed in 67% (30/39) of primary melanomas and 54% (11/21) of metastases. Although bcl-2 immunoreactivity was observed in all levels of primary cutaneous malignant melanomas, in 43% (9/21) of deep melanomas (Clark level > or = III), and 100% (7/7) of thick tumors (thickness > or = 4.00 mm), there was focal loss of immunoreactivity. Metastatic melanomas showed focal loss of bcl-2 expression in 10% (2/21) of cases and total loss of bcl-2 protein in 39% (8/21). We conclude from our results that bcl-2 protein is expressed by benign and malignant melanocytic tumors of the skin, but there is loss of bcl-2 protein expression with increasing tumor progression.


Asunto(s)
Melanoma/metabolismo , Melanoma/patología , Proteínas Proto-Oncogénicas/biosíntesis , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Biomarcadores de Tumor/análisis , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática , Melanoma/genética , Melanoma/secundario , Nevo Pigmentado/metabolismo , Nevo Pigmentado/patología , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas/análisis , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas c-bcl-2 , Neoplasias Cutáneas/genética
20.
Am J Public Health ; 72(1): 55-7, 1982 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7053621

RESUMEN

Data from 40 patients attending a hypertension clinic staffed by physicians were compared to data from 40 patients attending a hypertension clinic staffed by nurses over a period of 15 months. Nurses appeared to have more success in handling obesity and to achieve somewhat better control of hypertension. Attrition rate was 50 per cent, but particularly high in patients not receiving medication in the physician clinic. There were no differences in appointment keeping.


Asunto(s)
Enfermeras Practicantes , Médicos , Atención Primaria de Salud , Femenino , Humanos , Hipertensión/terapia , Masculino , Manitoba , Persona de Mediana Edad , Obesidad/terapia , Calidad de la Atención de Salud
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