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1.
Environ Res ; 258: 119423, 2024 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-38889839

RESUMEN

High concentration of chromium in aquatic environments is the trigger for researchers to remediate it from wastewater environments. However, conventional water treatment methods have not been satisfactory in removing chromium from water and wastewater over the last decade. Similarly, many adsorption studies have been focused on one aspect of the treatment, but this study dealt with all aspects of adsorption packages to come up with a concrete conclusion. Therefore, this study aimed to prepare pinecone biochar (PBC) via pyrolysis and apply it for Cr(VI) removal from wastewater. The PBC was characterized using FTIR, SEM-EDX, BET surface area, pHpzc, Raman analyses, TGA, and XRD techniques. Chromium adsorption was studied under the influence of PBC dose, solution pH, initial Cr(VI) concentration, and contact time. The characteristics of PBC are illustrated by FTIR spectroscopic functional groups, XRD non-crystallite structure, SEM rough surface morphology, and high BET surface area125 m2/g, pore volume, 0.07 cm3/g, and pore size 1.4 nm. On the other hand, the maximum Cr (VI) adsorption of 69% was found at the experimental condition of pH 2, adsorbent dosage 0.25 mg/50 mL, initial Cr concentration 100 mg/L, and contact time of 120 min. Similarly, the experimental data were well-fitted with the Langmuir adsorption isotherm at R2 0.96 and the pseudo-second-order kinetics model at R2 0.99. This implies the adsorption process is mainly attributed to monolayer orientation between the adsorbent and adsorbate. In the thermodynamics study of adsorption, ΔG was found to be negative implying the adsorption process was feasible and spontaneous whereas the positive values of ΔH and ΔS indicated the adsorption process was endothermic and increasing the degree of randomness, respectively. Finally, adsorbent regeneration and reusability were successful up to three cycles. In conclusion, biochar surface modification and reusability improvements are urgently required before being applied at the pilot scale.

2.
Heliyon ; 8(2): e08945, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35243067

RESUMEN

The present study aimed to characterize the bacterial community and functional diversity in co-composting microcosms of crude oil waste sludge amended with different animal manures, and to evaluate the scope for biostimulation based in situ bioremediation. Gas chromatography-mass spectrometry (GC-MS) analyses revealed enhanced attenuation (>90%) of the total polyaromatic hydrocarbons (PAHs); the manure amendments significantly enhancing (up to 30%) the degradation of high molecular weight (HMW) PAHs. Microbial community analysis showed the dominance (>99% of total sequences) of sequences affiliated to phyla Proteobacteria, Firmicutes, Actinobacteria and Bacteroidetes. The core genera enriched were related to hydrocarbon metabolism (Pseudomonas, Delftia, Methylobacterium, Dietzia, Bacillus, Propionibacterium, Bradyrhizobium, Streptomyces, Achromobacter, Microbacterium and Sphingomonas). However, manure-treated samples exhibited high number and heterogeneity of unique operational taxonomic units (OTUs) with enrichment of additional hydrocarbon-degrading bacterial taxa (Proteiniphilum, unclassified Micrococcales, unclassified Lachnospiraceae, Sphingobium and Stenotrophomonas). Thirty-three culturable hydrocarbon-degrading microbes were isolated from the co-composting microcosms and mainly classified into Burkholderia, Sanguibacter, Pseudomonas, Bacillus, Rhodococcus, Lysinibacillus, Microbacterium, Brevibacterium, Geobacillus, Micrococcus, Arthrobacter, Cellulimicrobacterium, Streptomyces Dietzia,etc,. that was additionally affirmed with the presence of catechol 2,3-dioxygenase gene. Finally, enhanced in situ degradation of total (49%), LMW (>75%) and HMW PAHs (>35%) was achieved with an enriched bacterial consortium of these microbes. Overall, these findings suggests that co-composting treatment of crude oil sludge with animal manures selects for intrinsically diverse bacterial community, that could be a driving force behind accelerated bioremediation, and can be exploited for engineered remediation processes.

3.
HIV Med ; 20(9): 628-633, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31274241

RESUMEN

OBJECTIVES: Since 2013, the London HIV Mortality Review Group has conducted annual reviews of deaths among people with HIV to reduce avoidable mortality. METHODS: All London HIV care Trusts reported data on 2016 patient deaths in 2017. Deaths were submitted using a modified Causes of Death in HIV reporting form and categorized by a specialist HIV pathologist and two HIV clinicians. RESULTS: There were 206 deaths reported; 77% were among men. Median age at death was 56 years. Cause was established for 82% of deaths, with non-AIDS-related malignancies and AIDS-defining illnesses being the most common causes reported. Risk factors in the year before death included: tobacco smoking (37%), excessive alcohol consumption (19%), non-injecting drug use (10%), injecting drug use (7%) and opioid substitution therapy (6%). Thirty-nine per cent of patients had a history of depression, 33% chronic hypertension, 27% dyslipidaemia, 17% coinfection with hepatitis B virus and/or hepatitis C virus and 14% diabetes mellitus. At the time of death, 81% of patients were on antiretroviral therapy (ART), 61% had a CD4 count < 350 cells/µL, and 24% had a viral load ≥ 200 HIV-1 RNA copies/mL. Thirty-six per cent of deaths were unexpected; 61% of expected deaths were in hospital. Two-thirds of expected deaths had a prior end-of-life care discussion documented. CONCLUSIONS: In 2016, most deaths were attributable to non-AIDS-related conditions and the majority of patients were on ART and virally suppressed. However, several potentially preventable deaths were identified and underlying risk factors were common. As London HIV patients are not representative of people with HIV in the UK, a national mortality review is warranted.


Asunto(s)
Terapia Antirretroviral Altamente Activa/estadística & datos numéricos , Causas de Muerte , Coinfección/mortalidad , Infecciones por VIH/mortalidad , Síndrome de Inmunodeficiencia Adquirida , Adulto , Recuento de Linfocito CD4 , Enfermedades Cardiovasculares/mortalidad , Diabetes Mellitus/mortalidad , Femenino , Encuestas Epidemiológicas , Hepatitis Viral Humana/mortalidad , Humanos , Londres/epidemiología , Masculino , Persona de Mediana Edad , Neoplasias/mortalidad , Factores de Riesgo , Trastornos Relacionados con Sustancias/mortalidad , Carga Viral
4.
Springerplus ; 5(1): 1946, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27933233

RESUMEN

BACKGROUND: The use of microorganisms in remediating environmental contaminants such as crude oil sludge has become a promising technique owing to its economy and the fact it is environmentally friendly. Polycyclic aromatic hydrocarbons (PAHs), as the major components of oil sludge, are hydrophobic and recalcitrant. An important way of enhancing the rate of PAH desorption is to compost crude oil sludge by incorporating commercial surfactants, thereby making them available for microbial degradation. In this study, crude oil sludge was composted for 16 weeks during which surfactants were added in the form of a solution. RESULTS: Molecular characterisation of the 16S rRNA genes indicated that the isolates obtained on a mineral salts medium belonged to different genera, including Stenotrophmonas, Pseudomonas, Bordetella, Brucella, Bacillus, Achromobacter, Ochrobactrum, Advenella, Mycobacterium, Mesorhizobium, Klebsiella, Pusillimonas and Raoultella. The percentage degradation rates of these isolates were estimated by measuring the absorbance of the 2,6-dichlorophenol indophenol medium. Pseudomonas emerged as the top degrader with an estimated percentage degradation rate of 73.7% after 7 days of incubation at 28 °C. In addition, the presence of the catabolic gene, catechol-2,3-dioxygenase was detected in the bacteria isolates as well as in evolutionary classifications based on phylogeny. CONCLUSIONS: The bacteria isolated in this study are potential agents for the bioremediation of crude oil sludge.

5.
Environ Monit Assess ; 185(12): 10201-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23856811

RESUMEN

Constructing various green wetland examples for mangrove wetland systems is a useful way to use natural power to remediate the polluted wetlands at intertidal zones. Metallothioneins (MT) are involved in heavy metal tolerance, homeostasis, and detoxification of intracellular metal ions in plants. In order to understand the mechanism of heavy metal uptake in Aegiceras corniculatum, we isolated its metallothionein gene and studied the MT gene expression in response to heavy metals contamination. Here, we report the isolation and characterization of MT2 genes from young stem tissues of A. corniculatum growing in the cadmium (Cd) and lead (Pb) polluted wetlands of Quanzhou Bay, southeast of China. The obtained cDNA sequence of MT is 512 bp in length, and it has an open reading frame encoding 79 amino acid residues with a molecular weight of 7.92 kDa and the theoretical isoelectric point of 4.55. The amino acids include 14 cysteine residues and 14 glycine residues. It is a non-transmembrane hydrophilic protein. Sequence and homology analysis showed the MT protein sequence shared more than 60% homology with other plant type 2 MT-like protein genes. The results suggested that the expression level of MT gene of A. corniculatum young stems induced by a certain range concentration of Cd(2+) and Pb(2+) stresses (0.2 mmol L(-1) Pb(2+), 1 mmol L(-1) Pb(2+), 0.2 mmol L(-1) Pb(2+), and 40 µmmol L(-1) Cd(2+); 1 mmol L(-1) Pb(2+) and 40 µmol L(-1) Cd(2+)) compared with control might show an adaptive protection. The expression levels of MT gene at 20 h stress treatment were higher than those at 480 h stress treatment. The expression levels of MT gene with 0.2 mmol L(-1) Pb(2+) stress treatment were higher than those with 0.2 mmol L(-1) Pb(2+) and 40 µmol L(-1) Cd(2+) stress treatment, and the MT gene expression levels with 1 mmol L(-1) Pb(2+) treatment were higher than those with 1 mmol L(-1) Pb(2+) and 40 µmol L(-1) Cd(2+) treatment. There exists an antagonistic action between Pb(2+) and Cd(2+) in the MT metabolization of A. corniculatum.


Asunto(s)
Metalotioneína/genética , Metales Pesados/toxicidad , Primulaceae/genética , Secuencia de Aminoácidos , Secuencia de Bases , Cadmio/análisis , Cadmio/toxicidad , China , ADN Complementario/metabolismo , Monitoreo del Ambiente , Expresión Génica , Plomo/análisis , Plomo/toxicidad , Metalotioneína/metabolismo , Metales Pesados/análisis , Datos de Secuencia Molecular , Primulaceae/metabolismo , Humedales
6.
J Chem Phys ; 136(6): 061101, 2012 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-22360161

RESUMEN

Effusive molecular beam measurements of angle-resolved thermal dissociative sticking coefficients for CH(4) impinging on a Pt(111) surface, at a temperature of 700 K, are reported and compared to theoretical predictions. The reactivity falls off steeply as the molecular angle of incidence increases away from the surface normal. Successful modeling of the thermal dissociative sticking behavior, consistent with existent CH(4) supersonic molecular beam experiments involving rotationally cold molecules, required that rotation be treated as a spectator degree of freedom.

7.
Rev Sci Instrum ; 82(4): 044102, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21529024

RESUMEN

An effusive molecular beam technique is described to measure alkane dissociative sticking coefficients, S(T(g), T(s); ϑ), on metal surfaces for which the impinging gas temperature, T(g), and surface temperature, T(s), can be independently varied, along with the angle of incidence, ϑ, of the impinging gas. Effusive beam experiments with T(g) = T(s) = T allow for determination of angle-resolved dissociative sticking coefficients, S(T; ϑ), which when averaged over the cos (ϑ)/π angular distribution appropriate to the impinging flux from a thermal ambient gas yield the thermal dissociative sticking coefficient, S(T). Nonequilibrium S(T(g), T(s); ϑ) measurements for which T(g) ≠ T(s) provide additional opportunities to characterize the transition state and gas-surface energy transfer at reactive energies. A resistively heated effusive molecular beam doser controls the T(g) of the impinging gas striking the surface. The flux of molecules striking the surface from the effusive beam is determined from knowledge of the dosing geometry, chamber pressure, and pumping speed. Separate experiments with a calibrated leak serve to fix the chamber pumping speed. Postdosing Auger electron spectroscopy is used to measure the carbon of the alkyl radical reaction product that is deposited on the surface as a result of alkane dissociative sticking. As implemented in a typical ultrahigh vacuum chamber for surface analysis, the technique has provided access to a dynamic range of roughly 6 orders of magnitude in the initial dissociative sticking coefficient for small alkanes on Pt(111).

8.
Virology ; 415(1): 47-55, 2011 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-21514617

RESUMEN

Lv2 is a human factor that restricts infection of some HIV-2 viruses after entry into particular target cells. HIV-2 MCR is highly susceptible to Lv2 whereas HIV-2 MCN is not. The block is after reverse transcription but prior to nuclear entry. The viral determinants for this restriction have been mapped to the HIV-2 envelope and the capsid genes. Our model of Lv2 restriction suggests that the route taken into a cell is important in determining whether a productive infection occurs. Here we characterised the infectious routes used by MCN and MCR using chemical compounds and molecular techniques to distinguish between potential pathways. Our results suggest that susceptible MCR can enter restrictive HeLa(CD4) cells via two pathways; a clathrin/AP2 mediated endocytic route that is sensitive to Lv2 restriction and an alternative, non-clathrin mediated route, which results in more efficient infection.


Asunto(s)
Actinas/metabolismo , Clatrina/metabolismo , Endocitosis , VIH-2/fisiología , Internalización del Virus/efectos de los fármacos , Complejo 2 de Proteína Adaptadora/metabolismo , Western Blotting , Línea Celular Tumoral , Endocitosis/efectos de los fármacos , Productos del Gen env/genética , Productos del Gen env/metabolismo , VIH-2/genética , Células HeLa , Humanos , Lípidos de la Membrana/genética , Mutación , ARN Interferente Pequeño , Proteínas del Envoltorio Viral/efectos de los fármacos , Proteínas del Envoltorio Viral/genética
9.
Psychol Med ; 38(1): 79-88, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17532864

RESUMEN

BACKGROUND: The impact of co-morbid substance use in first-episode schizophrenia has not been fully explored. METHOD: This naturalistic follow-up of a cohort of 152 people with first-episode schizophrenia examined substance use and clinical outcome in terms of symptoms and social and neuropsychological function. RESULTS: Data were collected on 85 (56%) of the patient cohort after a median period of 14 months. Over the follow-up period, the proportion of smokers rose from 60% at baseline to 64%. While 30% reported lifetime problem drinking of alcohol at baseline, only 15% had problem drinking at follow-up. Furthermore, while at baseline 63% reported lifetime cannabis use and 32% were currently using the drug, by the follow-up assessment the latter figure had fallen to 18.5%. At follow-up, persistent substance users had significantly more severe positive and depressive symptoms and greater overall severity of illness. A report of no lifetime substance use at baseline was associated with greater improvement in spatial working memory (SWM) at follow-up. CONCLUSIONS: Past substance use may impede recovery of SWM performance in people with schizophrenia in the year or so following first presentation to psychiatric services. The prevalence of substance use other than tobacco tends to diminish over this period, in the absence of specific interventions. Persistent substance use in first-episode schizophrenia is associated with more severe positive and depressive symptoms but not negative symptoms, and should be a target for specific treatment intervention.


Asunto(s)
Esquizofrenia/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Adulto , Trastornos Relacionados con Alcohol/diagnóstico , Trastornos Relacionados con Alcohol/epidemiología , Estudios de Cohortes , Comorbilidad , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/epidemiología , Diagnóstico Dual (Psiquiatría) , Femenino , Estudios de Seguimiento , Humanos , Londres/epidemiología , Masculino , Abuso de Marihuana/diagnóstico , Abuso de Marihuana/epidemiología , Pruebas Neuropsicológicas/estadística & datos numéricos , Prevalencia , Escalas de Valoración Psiquiátrica/estadística & datos numéricos , Esquizofrenia/diagnóstico , Índice de Severidad de la Enfermedad , Ajuste Social , Trastornos Relacionados con Sustancias/diagnóstico , Tabaquismo/diagnóstico , Tabaquismo/epidemiología
10.
Sci Total Environ ; 385(1-3): 262-71, 2007 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-17673277

RESUMEN

Agrochemical contamination in groundwater poses a significant long term threat to water quality and is of concern for legislators, water utilities and consumers alike. In the dual porosity, dual permeability aquifers such as the Chalk aquifer, movement of pesticides and their metabolites through the unsaturated zone to groundwater is generally considered to be through one of two pathways; a rapid by-pass flow and a slower 'piston-flow' route via the rock matrix. However, the dissolved form or 'colloidal species' in which pesticides move within the water body is poorly understood. Following heavy rainfall, very high peaks in pesticide concentration have been observed in shallow Chalk aquifers. These concentrations might be well explained by colloidal transport of pesticides. We have sampled a Chalk groundwater beneath a deep (30 m) unsaturated zone known to be contaminated with the pesticide diuron. Using a tangential flow filtration technique we have produced colloidal fractions from 0.45 microm to 1 kDa. In addition, we have applied agricultural grade diuron to a typical Chalk soil and created a soil water suspension which was also subsequently fractionated using the same filtration system. The deep groundwater sample showed no evidence of association between colloidal material and pesticide concentration. In comparison, despite some evidence of particle trapping or sorption to the filters, the soil water clearly showed an association between the <0.45 microm and <0.1 microm colloidal fractions which displayed significantly higher pesticide concentrations than the unfiltered sample. Degradation products were also observed and found to behave in a similar manner to the parent compound. Although relatively large colloids can be generated in the Chalk soil zone, it appears transport to depth in a colloidal-bound form does not occur. Comparison with other field and monitoring studies suggests that rapid by-pass flow is unlikely to occur beneath 4-5 m. Therefore, shallow groundwaters are most at risk from rapid transport of high concentrations of pesticide-colloidal complexes. The presence of a deep unsaturated zone will mean that most of the colloidal-complexes will be filtered by the narrow Chalk pores and the majority of pesticide transport will occur in a 'dissolved' form through the more gradual 'piston-flow' route.


Asunto(s)
Carbonato de Calcio/química , Coloides/química , Agua Dulce/análisis , Sedimentos Geológicos/química , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Porosidad , Reino Unido , Movimientos del Agua
11.
J Contam Hydrol ; 53(3-4): 319-40, 2001 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11820476

RESUMEN

Investigation of a groundwater plume containing up to 24 g l(-1) phenolic compounds suggested that over a period of nearly 50 years, little degradation had occurred despite the presence of a microbial community and electron acceptors within the core of the plume. In order to study the effect of contaminant concentration on degradation behaviour, laboratory microcosm experiments were performed under aerobic and anaerobic conditions at four different concentrations obtained by diluting contaminated with uncontaminated groundwater. The microcosms contained groundwater with total phenols at ca. 200, 250, 660 and 5000 mg l(-1), and aquifer sediment that had been acclimatised within the plume for several months. The microcosms were operated for a period of 390-400 days along with sterile controls to ascertain whether degradation was microbially mediated or abiotic. Under aerobic conditions, degradation only occurred at concentrations up to 660 mg l(-1) total phenols. At phenol concentrations below 250 mg l(-1) a benzoquinone intermediate, thought to originate from the degradation of 2,5-dimethylphenol, was isolated and identified. This suggested an unusual degradative pathway for this compound; its aerobic degradation more commonly proceeding via catecholic intermediates. Under anaerobic conditions, degradation only occurred in the most dilute microcosm (total phenols 195 mg l(-1)) with a loss of p-cresol accompanied by a nonstoichiometric decrease in nitrate and sulphate. By inference, iron(III) from the sediment may also have been used as a terminal electron acceptor, in which case the amount of biologically available iron released was calculated as 1.07 mg Fe(III)/g of sediment. The study shows that natural attenuation is likely to be stimulated by dilution of the plume.


Asunto(s)
Bacterias/metabolismo , Alquitrán , Fenoles/análisis , Microbiología del Agua , Contaminantes Químicos del Agua/análisis , Aerobiosis , Anaerobiosis , Biodegradación Ambiental , Relación Dosis-Respuesta a Droga , Cinética , Eliminación de Residuos , Reino Unido
12.
Cytopathology ; 8(4): 230-5, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9252740

RESUMEN

A breast FNA cytology service for palpable breast lumps was commenced in 1989 using the cytospin method. Over the following 6 years 2314 aspirates were received. The results were audited in detail in 1990, 1991/1992 and 1994. Multidisciplinary clinical audit meetings followed each audit cycle. Practice change was agreed after each audit. Each audit cycle was followed by demonstrable improvement in the complete sensitivity of the technique, being respectively 79%, 88% and 96%. The cytospin method is a viable alternative to the conventional smear method.


Asunto(s)
Biopsia con Aguja/estadística & datos numéricos , Neoplasias de la Mama/diagnóstico , Auditoría Médica , Humanos , Sensibilidad y Especificidad
13.
Cornell Vet ; 81(4): 351-6, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1954739

RESUMEN

Excisional biopsy of a skin lesion was performed in 4 horses after stretching the surrounding skin with mattress sutures. The technique of presuturing allowed all biopsy wounds to be closed without excessive tension on the suture lines.


Asunto(s)
Biopsia/veterinaria , Procedimientos Quirúrgicos Dermatologicos , Caballos/cirugía , Técnicas de Sutura/veterinaria , Animales , Femenino , Masculino
14.
Radiat Res ; 127(3): 248-56, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1886979

RESUMEN

Flow cytometry and cell sorting techniques have been used together with repeated measurement in an attempt to define better the radiation survival response of asynchronously dividing Chinese hamster V79-171 cells under aerobic and hypoxic conditions. Although the first two decades of cell inactivation have been examined, particular attention has been given to the low-dose range of a few grays, as used in individual radiation therapy treatments. A single linear-quadratic dose-response function was consistently unable to fit both the low-dose and high-dose data satisfactorily, suggesting a two-component response. Separate fitting of the low-dose and high-dose portions of the response yielded alpha and beta values which differed significantly (P = 0.001 to 0.002). The data are consistent with the hypothesis that the observed substructure simply reflects the presence of subpopulations of sensitive (G1-, G2-phase) and resistant (late S-phase) cells, which are resolved in these measurements. These results may have significance for certain situations in radiation therapy and in biophysical modeling of the radiation response.


Asunto(s)
División Celular/fisiología , Supervivencia Celular/efectos de la radiación , Aerobiosis , Anaerobiosis , Animales , Células Cultivadas , Relación Dosis-Respuesta en la Radiación , Factores de Tiempo
15.
Radiat Res ; 127(3): 243-7, 1991 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1886978

RESUMEN

The dose dependence of the oxygen enhancement ratio (OER) has been examined through multiple measurements of the response of Chinese hamster V79-171 cells to low and high doses of radiation under aerobic and hypoxic conditions. In this series of experiments the cells were maintained at 37 degrees C throughout the gassing and irradiation periods, to simulate normal physiological conditions. Flow cytometry and cell sorting techniques were used to facilitate accurate measurement of cell survival throughout the dose range, but particularly at low dose. The OER was found to decrease significantly at low dose, qualitatively confirming earlier reports from this laboratory, though the decrease was somewhat smaller in the present series. This difference may be a temperature effect since in the earlier experiments irradiation was at 0 degree C. This report shows that the OER decreases from a value of 2.87 +/- 0.16 (standard deviation of mean) at S = 0.01 to 2.36 +/- 0.19 at S = 0.80. Both alpha and beta are altered by the presence of oxygen. The OER is presented as a function of dose in nitrogen.


Asunto(s)
Supervivencia Celular/efectos de la radiación , Oxígeno/fisiología , Aerobiosis , Anaerobiosis , Animales , Células Cultivadas , Relación Dosis-Respuesta en la Radiación
16.
Gut ; 32(5): 467-9, 1991 May.
Artículo en Inglés | MEDLINE | ID: mdl-2040465

RESUMEN

There are several reliable methods for detecting Helicobacter pylori but all have as a major disadvantage the time required to yield a definitive result. We have modified the standard urease test so that a positive result is available in one minute. We describe the use of this test in biopsy specimens from the gastric antrum from 220 consecutive patients referred for upper gastrointestinal endoscopy. The performance of the 'one minute test' was compared with a standard urease test, Gram stain, and microbiological culture. Using culture as the 'gold standard' 80 (36%) of the patients were H pylori positive. The one minute test produced no false positives and showed a sensitivity of 89% and specificity of 100%, while the predictive values of a positive and negative test were 100% and 94% respectively. The diagnostic efficiency of the test was 96% compared to 85% for both the Gram stain and direct urease test. All positive results using the one minute test were available within one minute. The test is easy to prepare and costs approximately pounds 0.04. This new modification of the urease test should be superior to the currently available urease tests because a reliable result will be available in almost 90% of infected individuals even before endoscopy is completed.


Asunto(s)
Mucosa Gástrica/microbiología , Infecciones por Helicobacter/diagnóstico , Helicobacter pylori/aislamiento & purificación , Adulto , Anciano , Anciano de 80 o más Años , Técnicas Bacteriológicas , Reacciones Falso Positivas , Femenino , Helicobacter pylori/enzimología , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Factores de Tiempo , Ureasa/metabolismo
17.
Cornell Vet ; 80(3): 279-84, 1990 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-2114253

RESUMEN

A nine-year-old gelding was presented to the Auburn University Large Animal Clinic with discharge of saliva and food material from both nostrils. A diagnosis of esophageal diverticulum was made; treatment is described.


Asunto(s)
Divertículo Esofágico/veterinaria , Enfermedades de los Caballos/cirugía , Heridas Penetrantes/veterinaria , Animales , Divertículo Esofágico/etiología , Divertículo Esofágico/cirugía , Esofagoscopía/veterinaria , Enfermedades de los Caballos/etiología , Caballos , Masculino , Heridas Penetrantes/complicaciones
18.
Surgery ; 105(6): 797-800, 1989 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2543093

RESUMEN

A case of synchronous carcinoma of the colon and the kidney with solitary metastatic nodules to each lung from each cancer is presented. The time interval between the original surgery and the first metastasis was 3 months and between the first and second metastases, 7 months. The patient underwent wedge resection of both metastases. Eight years after surgery he remains free of tumor.


Asunto(s)
Adenocarcinoma Mucinoso/secundario , Adenocarcinoma/secundario , Carcinoma de Células Renales/secundario , Neoplasias del Colon/patología , Neoplasias Renales/patología , Neoplasias Pulmonares/secundario , Neoplasias Primarias Múltiples , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Adenocarcinoma Mucinoso/patología , Adenocarcinoma Mucinoso/cirugía , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/cirugía , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad
19.
J Invest Surg ; 2(1): 75-84, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2487401

RESUMEN

This study evaluated the pony as a potentially suitable model for vascular implant research. Healthy, conditioned ponies were randomly assigned to one of three groups: group I, carotid artery autografts (n = 6); group II, e-PTFE carotid interpositional grafts (n = 5); and group III, e-PTFE carotid interpositional grafts plus aspirin (10 mg/kg) and dipyridamole (3.5 mg/kg) drug administration. It was found that autografts remained patent longest (mean = 396.2 days; grafts were still patent at time of writing) followed by group III grafts (157.5 days), with group II grafts remaining patent for the shortest duration (61.1 days), (p less than 0.01). Patency was determined using two-dimensional real-time ultrasonography with Doppler velocimetry and/or arteriography. It was demonstrated that the pony's response to antithrombotic drugs was consistent and comparable to that in other animal models, both with respect to platelet function and affect on patency rate. The combination of the ease of surgical manipulation, drug administration, and platelet function testing, the comparable size of the pony and its heart and blood vessels to that of an adult human, the long life span of ponies, and the patency results of this study have demonstrated that the pony is a valuable animal model for vascular research.


Asunto(s)
Prótesis Vascular , Arterias Carótidas/cirugía , Animales , Arterias Carótidas/diagnóstico por imagen , Arterias Carótidas/trasplante , Caballos , Ensayo de Materiales , Modelos Biológicos , Agregación Plaquetaria , Politetrafluoroetileno , Trombosis/etiología , Ultrasonografía
20.
Vet Surg ; 17(5): 252-7, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-3227636

RESUMEN

Left-sided partial arytenoidectomy was performed in eight horses to evaluate healing. Four horses underwent conventional partial arytenoidectomy with suture apposition of the mucosa. In four horses, most of the arytenoid cartilage, including overlying mucosa, vocal fold, and laryngeal saccule, were excised en bloc without mucosal closure. The horses were monitored clinically by endoscopic examination. One horse from each group was euthanatized at weeks 2, 4, 8, and 16. Complete necropsies with gross and histologic examination of the arytenoidectomy sites were performed. Postoperative complications such as coughing, dysphagia, and aspiration pneumonia were not encountered and problems with wound healing were minimal in both groups. The defect created by partial arytenoidectomy without mucosal closure initially filled to the level of the luminal surface with granulation tissue, with a gradual transition to mature fibrous connective tissue. Grossly, the defect appeared to be healed and was completely epithelialized by week 16 without apparent narrowing of the laryngeal lumen. Partial arytenoidectomy sites with mucosal closure healed in a similar pattern by week 8. Partial dehiscence of the dorsal portion of the sutured mucosa occurred in three horses.


Asunto(s)
Cartílago Aritenoides/cirugía , Enfermedades de los Caballos/cirugía , Cartílagos Laríngeos/cirugía , Enfermedades de la Laringe/veterinaria , Animales , Caballos , Enfermedades de la Laringe/cirugía , Mucosa Laríngea/patología , Masculino
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