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1.
Australas Psychiatry ; 31(1): 38-42, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36337038

RESUMEN

OBJECTIVE: To assess the COVID-19 vaccination rates of a severe mental illness (SMI) population in Western Australia (WA) in January to March 2022, and to evaluate an inpatient COVID-19 vaccination program available to this group. METHOD: A retrospective audit of the COVID-19 vaccination status of inpatients at the Mental Health Unit (MHU) at a tertiary hospital in WA was conducted and compared with the state average. Additionally, the medical records were interrogated to determine whether eligible inpatients were offered and received COVID-19 vaccination via the inpatient vaccination program. RESULTS: Vaccination rates for the MHU population were substantially lower than those for the WA population, particularly earlier in 2022. During January, just 49.0% of admitted patients had received two doses of the vaccine, compared to 92.8% of WA. Over the three months, 67 (47.2%) of all admissions were eligible for vaccination during their admission and 19 of the eligible patients (28.4%) were successfully vaccinated. CONCLUSION: This audit has demonstrated a slow uptake of COVID-19 vaccinations in the SMI population, despite the wide availability for 12 months prior to this period. This indicates a significant potential for targeted, assertive programs to improve vaccination rates in this population group.


Asunto(s)
COVID-19 , Salud Mental , Humanos , Pacientes Internos , Vacunas contra la COVID-19 , Estudios Retrospectivos , COVID-19/prevención & control , Australia/epidemiología , Vacunación
2.
JAMA ; 325(8): 742-750, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33620405

RESUMEN

Importance: Sepsis is a common syndrome with substantial morbidity and mortality. A combination of vitamin C, thiamine, and corticosteroids has been proposed as a potential treatment for patients with sepsis. Objective: To determine whether a combination of vitamin C, thiamine, and hydrocortisone every 6 hours increases ventilator- and vasopressor-free days compared with placebo in patients with sepsis. Design, Setting, and Participants: Multicenter, randomized, double-blind, adaptive-sample-size, placebo-controlled trial conducted in adult patients with sepsis-induced respiratory and/or cardiovascular dysfunction. Participants were enrolled in the emergency departments or intensive care units at 43 hospitals in the United States between August 2018 and July 2019. After enrollment of 501 participants, funding was withheld, leading to an administrative termination of the trial. All study-related follow-up was completed by January 2020. Interventions: Participants were randomized to receive intravenous vitamin C (1.5 g), thiamine (100 mg), and hydrocortisone (50 mg) every 6 hours (n = 252) or matching placebo (n = 249) for 96 hours or until discharge from the intensive care unit or death. Participants could be treated with open-label corticosteroids by the clinical team, with study hydrocortisone or matching placebo withheld if the total daily dose was greater or equal to the equivalent of 200 mg of hydrocortisone. Main Outcomes and Measures: The primary outcome was the number of consecutive ventilator- and vasopressor-free days in the first 30 days following the day of randomization. The key secondary outcome was 30-day mortality. Results: Among 501 participants randomized (median age, 62 [interquartile range {IQR}, 50-70] years; 46% female; 30% Black; median Acute Physiology and Chronic Health Evaluation II score, 27 [IQR, 20.8-33.0]; median Sequential Organ Failure Assessment score, 9 [IQR, 7-12]), all completed the trial. Open-label corticosteroids were prescribed to 33% and 32% of the intervention and control groups, respectively. Ventilator- and vasopressor-free days were a median of 25 days (IQR, 0-29 days) in the intervention group and 26 days (IQR, 0-28 days) in the placebo group, with a median difference of -1 day (95% CI, -4 to 2 days; P = .85). Thirty-day mortality was 22% in the intervention group and 24% in the placebo group. Conclusions and Relevance: Among critically ill patients with sepsis, treatment with vitamin C, thiamine, and hydrocortisone, compared with placebo, did not significantly increase ventilator- and vasopressor-free days within 30 days. However, the trial was terminated early for administrative reasons and may have been underpowered to detect a clinically important difference. Trial Registration: ClinicalTrials.gov Identifier: NCT03509350.


Asunto(s)
Antiinflamatorios/uso terapéutico , Ácido Ascórbico/uso terapéutico , Hidrocortisona/uso terapéutico , Respiración Artificial , Sepsis/tratamiento farmacológico , Tiamina/uso terapéutico , Vitaminas/uso terapéutico , Adulto , Anciano , Enfermedad Crítica , Método Doble Ciego , Quimioterapia Combinada , Terminación Anticipada de los Ensayos Clínicos , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Puntuaciones en la Disfunción de Órganos , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Sepsis/complicaciones , Sepsis/mortalidad , Sepsis/terapia , Resultado del Tratamiento , Vasoconstrictores/uso terapéutico
3.
Pediatr Crit Care Med ; 20(3): 259-261, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30431555

RESUMEN

OBJECTIVES: Pediatric procedural sedation has been increasingly performed by pediatric intensivists over the past decade. Pediatric Critical Care Medicine fellowship guidelines do not specify how fellows obtain proficiency in pediatric procedural sedation. We sought to survey the state of pediatric procedural sedation training during fellowship and whether fellows thought it was sufficient. DESIGN: A 21-question survey gathered data on pediatric procedural sedation training provided to Pediatric Critical Care Medicine fellows. Surveys were sent to fellowship directors with instructions to distribute to second- and third-year fellows or recent graduates. Over 2 months, up to three e-mail reminders were sent to fellowship directors whose program had not completed at least one survey. SUBJECTS: Senior fellows and graduates of 65 active Accreditation Council for Graduate Medical Education Pediatric Critical Care Medicine fellowship programs. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Sixty-five percent of fellowship programs (42/65) returned at least one response. Ninety senior fellows and 27 recent graduates responded. Of respondents, 38% received pediatric procedural sedation training during the fellowship, and 32% reported mandatory training. Nine percent of programs used simulation. Although 61% who received training felt adequately prepared to perform pediatric procedural sedation, 25% needed additional preceptorship to sedate independently. Nearly one third (31%) reported that completion of a predetermined number of cases was required to sedate independently. Forty-eight percent reported a minimum number of cases was required for hospital credentialing. Nearly 45% were allowed to perform pediatric procedural sedation off the unit after receiving credentials. When asked if inadequate pediatric procedural sedation training would be a deterrent to applying for a position that included pediatric procedural sedation, 8.6% replied yes, 52.6% replied no, and 38.8% replied they were unsure. CONCLUSIONS: Pediatric procedural sedation lacks a clearly defined training pathway. Most fellows find pediatric procedural sedation a valuable skill set. We propose that all Pediatric Critical Care Medicine fellows receive training that includes pediatric procedural sedation critical incident simulation and cases performed outside the PICU to establish proficiency.


Asunto(s)
Anestesia/métodos , Cuidados Críticos/estadística & datos numéricos , Educación de Postgrado en Medicina/estadística & datos numéricos , Becas/estadística & datos numéricos , Adulto , Anestesia/normas , Femenino , Humanos , Masculino , Estados Unidos
4.
Ecotoxicol Environ Saf ; 142: 79-86, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28390242

RESUMEN

Double-crested cormorants (Phalacrocorax auritus, DCCO) were orally exposed to Deepwater Horizon Mississippi Canyon 252 (DWH) oil to investigate oil-induced toxicological impacts. Livers were collected for multiple analyses including cytochrome P4501A (CYP1A) enzymatic activity and protein expression. CYP1A enzymatic activity was measured by alkoxyresorufin O-dealkylase (AROD) assays. Activities specific to the O-dealkylation of four resorufin ethers are reported: benzyloxyresorufin O-debenzylase (BROD), ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), and pentoxyresorufin O-depentylase (PROD). CYP1A protein expression was measured by western blot analysis with a CYP1A1 mouse monoclonal antibody. In study 1, hepatic BROD, EROD, and PROD activities were significantly induced in DCCO orally exposed to 20ml/kg body weight (bw) oil as a single dose or daily for 5 days. Western blot analysis revealed hepatic CYP1A protein induction in both treatment groups. In study 2 (5ml/kg bw oil or 10ml/kg bw oil, 21day exposure), all four hepatic ARODs were significantly induced. Western blots showed an increase in hepatic CYP1A expression in both treatment groups with a significant induction in birds exposed to 10ml/kg oil. Significant correlations were detected among all 4 AROD activities in both studies and between CYP1A protein expression and both MROD and PROD activities in study 2. EROD activity was highest for both treatment groups in both studies while BROD activity had the greatest fold-induction. While PROD activity values were consistently low, the fold-induction was high, usually 2nd highest to BROD activity. The observed induced AROD profiles detected in the present studies suggest both CYP1A4/1A5 DCCO isoforms are being induced after MC252 oil ingestion. A review of the literature on avian CYP1A AROD activity levels and protein expression after exposure to CYP1A inducers highlights the need for species-specific studies to accurately evaluate avian exposure to oil.

5.
Ecotoxicol Environ Saf ; 146: 68-75, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28571624

RESUMEN

Double-crested cormorants (Phalacrocorax auritus, DCCO) were orally exposed to Deepwater Horizon Mississippi Canyon 252 (DWH) oil to investigate oil-induced toxicological impacts. Livers were collected for multiple analyses including cytochrome P4501A (CYP1A) enzymatic activity and protein expression. CYP1A enzymatic activity was measured by alkoxyresorufin O-dealkylase (AROD) assays. Activities specific to the O-dealkylation of four resorufin ethers are reported: benzyloxyresorufin O-debenzylase (BROD), ethoxyresorufin O-deethylase (EROD), methoxyresorufin O-demethylase (MROD), and pentoxyresorufin O-depentylase (PROD). CYP1A protein expression was measured by western blot analysis with a CYP1A1 mouse monoclonal antibody. In study 1, hepatic BROD, EROD, and PROD activities were significantly induced in DCCO orally exposed to 20ml/kg body weight (bw) oil as a single dose or daily for 5 days. Western blot analysis revealed hepatic CYP1A protein induction in both treatment groups. In study 2 (5ml/kg bw oil or 10ml/kg bw oil, 21day exposure), all four hepatic ARODs were significantly induced. Western blots showed an increase in hepatic CYP1A expression in both treatment groups with a significant induction in birds exposed to 10ml/kg oil. Significant correlations were detected among all 4 AROD activities in both studies and between CYP1A protein expression and both MROD and PROD activities in study 2. EROD activity was highest for both treatment groups in both studies while BROD activity had the greatest fold-induction. While PROD activity values were consistently low, the fold-induction was high, usually 2nd highest to BROD activity. The observed induced AROD profiles detected in the present studies suggest both CYP1A4/1A5 DCCO isoforms are being induced after MC252 oil ingestion. A review of the literature on avian CYP1A AROD activity levels and protein expression after exposure to CYP1A inducers highlights the need for species-specific studies to accurately evaluate avian exposure to oil.

6.
Crit Care Med ; 43(8): 1595-602, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25867906

RESUMEN

OBJECTIVES: To determine whether addition of an electronic sepsis evaluation and management tool to electronic sepsis alerting improves compliance with treatment guidelines and clinical outcomes in septic ICU patients. DESIGN: A pragmatic randomized trial. SETTING: Medical and surgical ICUs of an academic, tertiary care medical center. PATIENTS: Four hundred and seven patients admitted during a 4-month period to the medical or surgical ICU with a diagnosis of sepsis established at the time of admission or in response to an electronic sepsis alert. INTERVENTIONS: Patients were randomized to usual care or the availability of an electronic tool capable of importing, synthesizing, and displaying sepsis-related data from the medical record, using logic rules to offer individualized evaluations of sepsis severity and response to therapy, informing users about evidence-based guidelines, and facilitating rapid order entry. MEASUREMENTS AND MAIN RESULTS: There was no difference between the electronic tool (218 patients) and usual care (189 patients) with regard to the primary outcome of time to completion of all indicated Surviving Sepsis Campaign 6-hour Sepsis Resuscitation Bundle elements (hazard ratio, 1.98; 95% CI, 0.75-5.20; p = 0.159) or time to completion of each element individually. ICU mortality, ICU-free days, and ventilator-free days did not differ between intervention and control. Providers used the tool to enter orders in only 28% of available cases. CONCLUSIONS: A comprehensive electronic sepsis evaluation and management tool is feasible and safe but did not influence guideline compliance or clinical outcomes, perhaps due to low utilization.


Asunto(s)
Sistemas de Apoyo a Decisiones Clínicas , Unidades de Cuidados Intensivos/normas , Sepsis/diagnóstico , Sepsis/terapia , Centros Médicos Académicos , Adulto , Anciano , Femenino , Adhesión a Directriz , Mortalidad Hospitalaria , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Guías de Práctica Clínica como Asunto , Índice de Severidad de la Enfermedad , Choque Séptico/diagnóstico , Choque Séptico/terapia , Método Simple Ciego
11.
Crit Care Med ; 40(7): 2096-101, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22584763

RESUMEN

OBJECTIVE: To determine whether automated identification with physician notification of the systemic inflammatory response syndrome in medical intensive care unit patients expedites early administration of new antibiotics or improvement of other patient outcomes in patients with sepsis. DESIGN: : A prospective randomized, controlled, single center study. SETTING: Medical intensive care unit of an academic, tertiary care medical center. PATIENTS: Four hundred forty-two consecutive patients admitted over a 4-month period who met modified systemic inflammatory response syndrome criteria in a medical intensive care unit. INTERVENTION: Patients were randomized to monitoring by an electronic "Listening Application" to detect modified (systemic inflammatory response syndrome) criteria vs. usual care. The listening application notified physicians in real time when modified systemic inflammatory response syndrome criteria were detected, but did not provide management recommendations. MEASUREMENTS AND MAIN RESULTS: The median time to new antibiotics was similar between the intervention and usual care groups when comparing among all patients (6.0 hr vs. 6.1 hr, p = .95), patients with sepsis (5.3 hr vs. 5.1 hr; p = .90), patients on antibiotics at enrollment (5.2 hr vs. 7.0 hr, p = .27), or patients not on antibiotics at enrollment (5.2 hr vs. 5.1 hr, p = .85). The amount of fluid administered following detection of modified systemic inflammatory response syndrome criteria was similar between groups whether comparing all patients or only patients who were hypotensive at enrollment. Other clinical outcomes including intensive care unit length of stay, hospital length of stay, and mortality were not shown to be different between patients in the intervention and control groups. CONCLUSIONS: Realtime alerts of modified systemic inflammatory response syndrome criteria to physicians in one tertiary care medical intensive care unit were feasible and safe but did not influence measured therapeutic interventions for sepsis or significantly alter clinical outcomes.


Asunto(s)
Diagnóstico Precoz , Sistemas de Información en Hospital , Sepsis/diagnóstico , Antibacterianos/uso terapéutico , Femenino , Fluidoterapia/estadística & datos numéricos , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación/estadística & datos numéricos , Masculino , Sistemas de Registros Médicos Computarizados , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y Especificidad , Sepsis/terapia
12.
Arch Environ Contam Toxicol ; 61(4): 653-67, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21424223

RESUMEN

From September to November 2000, United States Fish and Wildlife Service biologists investigated incidents involving 221 bird deaths at 3 mine sites located in New Mexico and Arizona. These bird deaths primarily involved passerine and waterfowl species and were assumed to be linked to consumption of acid metalliferous water (AMW). Because all of the carcasses were found in or near pregnant leach solution ponds, tailings ponds, and associated lakes or storm water retention basins, an acute-toxicity study was undertaken using a synthetic AMW (SAMW) formulation based on the contaminant profile of a representative pond believed to be responsible for avian mortalities. An acute oral-toxicity trial was performed with a mixed-sex group of mallards (Anas platyrhynchos). After a 24-h pretreatment food and water fast, gorge drinking was evident in both SAMW treatment and control groups, with water consumption rates greatest during the initial drinking periods. Seven of nine treated mallards were killed in extremis within 12 h after the initiation of dose. Total lethal doses of SAMW ranged from 69.8 to 270.1 mL/kg (mean ± SE 127.9 ± 27.1). Lethal doses of SAMW were consumed in as few as 20 to 40 min after first exposure. Clinical signs of SAMW toxicity included increased serum uric acid, aspartate aminotransferase, creatine kinase, potassium, and P levels. PCV values of SAMW-treated birds were also increased compared with control mallards. Histopathological lesions were observed in the esophagus, proventriculus, ventriculus, and duodenum of SAMW-treated mallards, with the most distinctive being erosion and ulceration of the kaolin of the ventriculus, ventricular hemorrhage and/or congestion, and duodenal hemorrhage. Clinical, pathological, and tissue-residue results from this study are consistent with literature documenting acute metal toxicosis, especially copper (Cu), in avian species and provide useful diagnostic profiles for AMW toxicity or mortality events. Blood and kidney Cu concentrations were 23- and 6-fold greater, respectively, in SAMW mortalities compared with controls, whereas Cu concentrations in liver were not nearly as increased, suggesting that blood and kidney concentrations may be more useful than liver concentrations for diagnosing Cu toxicosis in wild birds. Based on these findings and other reports of AMW toxicity events in wild birds, we conclude that AMW bodies pose a significant hazard to wildlife that come in contact with them.


Asunto(s)
Patos , Metales Pesados/toxicidad , Metales Ligeros/toxicidad , Contaminantes Químicos del Agua/toxicidad , Administración Oral , Animales , Conducta Animal/efectos de los fármacos , Ingestión de Líquidos/efectos de los fármacos , Conducta de Ingestión de Líquido/efectos de los fármacos , Monitoreo del Ambiente/métodos , Femenino , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/patología , Concentración de Iones de Hidrógeno , Riñón/efectos de los fármacos , Riñón/patología , Longevidad/efectos de los fármacos , Masculino , Metales Pesados/química , Metales Ligeros/química , Ácido Nítrico/química , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/patología , Pruebas de Toxicidad Aguda
13.
J Athl Train ; 55(5): 522-531, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32239964

RESUMEN

CONTEXT: The skill sets of athletic trainers (ATs) provide a unique contribution to the US military's optimization of physical readiness, and these positions are becoming more prevalent. However, knowledge regarding the job characteristics of, and ATs' preparation for, employment in a military setting is limited. OBJECTIVE: To assess the position and clinician characteristics of ATs working with military members and document their perceptions of working in the military setting. DESIGN: Cross-sectional study. SETTING: Online survey. PATIENTS OR OTHER PARTICIPANTS: A total of 53 ATs who currently or formerly worked in the military setting. DATA COLLECTION AND ANALYSIS: A Web-based survey with closed- and open-ended questions was distributed via e-mail and social media. Closed-ended data were analyzed via descriptive statistics, and open-ended questions were evaluated for common themes using thematic analysis. RESULTS: Respondents were primarily males (n = 31, 58.5%), had a master's degree (n = 42, 79.2%), and were not current or former service members (n = 46, 86.8%). Positions were primarily full time (n = 50, 94.3%), contracted with an independent company (n = 27, 50.9%), and within the Army (n = 24, 45.3%). The ATs were highly satisfied with their workload and ability to apply their skill set. Qualitative analysis revealed 3 themes: (1) the context of clinical practice in the military (eg, rewarding, job scope, military environment), (2) the importance of clinical and interpersonal skills, and (3) the existence of multiple barriers (eg, hiring, military culture, lack of recognition). CONCLUSIONS: Overall, ATs working in the military setting were well-qualified practitioners who were very satisfied with their current positions, yet they also reported barriers, such as working within the military culture and lack of recognition of their skill set. Although ATs indicated a neutral belief that professional degree preparation was sufficient for this clinical practice setting, the qualitative themes provided additional career-preparation advice for individuals interested in this setting.


Asunto(s)
Empleo , Personal Militar , Acondicionamiento Físico Humano , Adulto , Estudios Transversales , Femenino , Humanos , Satisfacción en el Trabajo , Masculino , Cultura Organizacional , Acondicionamiento Físico Humano/psicología , Salarios y Beneficios , Habilidades Sociales , Encuestas y Cuestionarios , Carga de Trabajo
14.
Artículo en Inglés | MEDLINE | ID: mdl-32770800

RESUMEN

Efficient biodiversity surveys are critical for successful restoration monitoring and management. We studied the effect of varying sampling effort on the observed species richness of surveys of small mammals (trapping transects), bats (passive acoustic detection), and medium to large mammals (trail cameras). Field studies provided mammalian biodiversity data for 4 bottomland hardwood restoration sites in northeastern Indiana. Subsampled data were used to simulate monitoring surveys with a range of levels of effort. We then used hierarchical Bayesian nonlinear mixed models to analyze how different components of sampling effort affected observed species richness, a key monitoring outcome. We found that observed small mammal richness increased with the increased number of transects in a survey, while observed bat and medium to large mammal richness increased with the increased duration of sampling. Variation between sites was important for the observed richness of small mammals and bats but not for medium to large mammals. The key driver of richness observed in simulated surveys was related to the spatial scale at which target fauna interact with the habitat, with decreasing richness accompanied by a greater spatial scale of animal-habitat interactions. Our findings suggest taxon-specific recommendations for efficiently quantifying the mammalian diversity of managed sites. Integr Environ Assess Manag 2020;00:1-13. © 2020 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

18.
Ecol Appl ; 19(8): 2026-37, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20014576

RESUMEN

Locusts and grasshoppers cause considerable economic damage to agriculture worldwide. The Australian Plague Locust Commission uses multiple pesticides to control locusts in eastern Australia. Avian exposure to agricultural pesticides is of conservation concern, especially in the case of rare and threatened species. The aim of this study was to evaluate the probability of pesticide exposure of native avian species during operational locust control based on knowledge of species occurrence in areas and times of application. Using presence-absence data provided by the Birds Australia Atlas for 1998 to 2002, we developed a series of generalized linear models to predict avian occurrences on a monthly basis in 0.5 degrees grid cells for 280 species over 2 million km2 in eastern Australia. We constructed species-specific models relating occupancy patterns to survey date and location, rainfall, and derived habitat preference. Model complexity depended on the number of observations available. Model output was the probability of occurrence for each species at times and locations of past locust control operations within the 5-year study period. Given the high spatiotemporal variability of locust control events, the variability in predicted bird species presence was high, with 108 of the total 280 species being included at least once in the top 20 predicted species for individual space-time events. The models were evaluated using field surveys collected between 2000 and 2005, at sites with and without locust outbreaks. Model strength varied among species. Some species were under- or over-predicted as times and locations of interest typically did not correspond to those in the prediction data set and certain species were likely attracted to locusts as a food source. Field surveys demonstrated the utility of the spatially explicit species lists derived from the models but also identified the presence of a number of previously unanticipated species. These results also emphasize the need for special consideration of rare and threatened species that are poorly predicted by presence-absence models. This modeling exercise was a useful a priori approach in species risk assessments to identify species present at times and locations of locust control applications, and to discover gaps in our knowledge and need for further focused data collection.


Asunto(s)
Aves/fisiología , Saltamontes/fisiología , Control de Insectos/métodos , Agricultura/economía , Animales , Australia , Conservación de los Recursos Naturales , Demografía , Contaminantes Ambientales/efectos adversos , Modelos Biológicos , Plaguicidas/efectos adversos , Especificidad de la Especie , Factores de Tiempo
19.
Environ Toxicol Chem ; 28(3): 534-41, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18980388

RESUMEN

A century of mining and smelting activity at the Anaconda Smelter site in Anaconda, Montana, USA, has contaminated the surrounding soils and groundwater with metals. Soil microbial communities from six smelter-impacted sites and a nonimpacted site were compared to determine the long-term effects of a gradient of metal concentrations on microbial activity, biomass, functional diversity (Biolog microtiter plates), and structural diversity (denaturant gradient gel electrophoresis of 16S ribosomal DNA). Microbial activity and biomass were decreased in the smelter-impacted soils. Likewise, the functional and structural diversity of the microbial communities native to the smelter-impacted soils were shifted, relative to the microbial community, from the nonimpacted site. These shifts were significantly correlated with soil metal concentration and several soil physicochemical properties (pH, organic matter, NO(3), NH(4), etc.), which provides evidence of the importance of many environmental variables on microbial community dynamics in soils. Preliminary evidence of functional redundancy was observed within microbial communities native to the smelter-impacted sites, based on overlapping carbon substrate utilization patterns. However, due to culture-based selection bias, redundancy pertains only to a subset of the community and may not be ecologically relevant. Nevertheless, the effects of metal contamination on microbial communities in the present study are pronounced and results provide preliminary insight into the complex relationship between soil microbial community structure and function in anthropogenically disturbed soils.


Asunto(s)
Residuos Industriales/análisis , Metales/química , Metales/toxicidad , Microbiología del Suelo , Contaminantes del Suelo/química , Biomasa , Minería , Suelo/análisis
20.
Ecotoxicol Environ Saf ; 72(5): 1572-8, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19328550

RESUMEN

Sensitivities of a wildlife species, deer mice, to oxidants were evaluated. A single dose (1589 mg/kg body weight by intraperitoneal injection) of carbon tetrachloride, a typical hepatotoxicant, caused changes in GCL activity and GSH content in multiple organs of deer mice. Hepatic GCL activity and GSH content were depleted substantially (P<0.01), renal GCL activity increased (P<0.05). Blood, brain and heart GCL activities increased (P<0.05), whereas GSH contents decreased significantly. Deer mice were exposed to Pb, or Pb together with Cu and Zn via drinking water for 4 weeks. GCL activities were not significantly affected by treatments. GSH contents were increased significantly by Pb alone, Pb with medium and high concentrations of Cu and Zn. Effects of multi-metal-contaminated soil were investigated via lactational, juvenile and lifelong exposure to feed supplemented with soils. Metal-contaminated soils did not lead to significant effects in pups via lactation, 50-day exposure altered GSH content marginally, while 100-day exposure resulted in marked GCL activity depletion. After 100-day exposure, GCL activities of the medium soil-, high soil- and Pb-treated deer mice were only 53%, 40% and 46% of the control, respectively (P<0.0001).


Asunto(s)
Tetracloruro de Carbono/toxicidad , Glutamato-Cisteína Ligasa/metabolismo , Glutatión/metabolismo , Metales Pesados/toxicidad , Oxidantes/toxicidad , Estrés Oxidativo/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Envejecimiento , Animales , Encéfalo/efectos de los fármacos , Encéfalo/enzimología , Tetracloruro de Carbono/administración & dosificación , Cobre/toxicidad , Femenino , Glutamato-Cisteína Ligasa/sangre , Glutatión/sangre , Inyecciones Intraperitoneales , Riñón/efectos de los fármacos , Riñón/enzimología , Plomo/toxicidad , Hígado/efectos de los fármacos , Hígado/enzimología , Masculino , Miocardio/enzimología , Oxidantes/administración & dosificación , Peromyscus , Medición de Riesgo , Zinc/toxicidad
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