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1.
WMJ ; 123(2): 106-112, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38718238

RESUMO

INTRODUCTION: Implicit racial bias, defined as unreasoned judgement based solely on an individual's skin color, is a persistent barrier to quality medical care for people of color in the United States. Early, learner-centered intervention is crucial to establish cultural competence within health professional training programs. METHODS: Over 3 academic years, preclinical, second-year medical students were asked to submit an anonymous critical reflection regarding skin tone in medicine (n=794). Critical reflection is an instructional approach that encourages students to investigate their own thoughts and actions. Course credit was given based on the honor system. Reflection submission content and student feedback were analyzed quantitatively and qualitatively using constructivist thematic analysis. RESULTS: Most students completed the assignment (93.0%) and reported feeling comfortable expressing themselves honestly in the anonymous format (84.6%). Students' comfort level with honesty declined if they would have had to identify themselves (50.8%). Student comments indicated relief to have a place to process experiences and emphasized the importance of anonymity for value of this assignment. Thematic analysis identified 2 themes and 13 subthemes among student submissions. Submissions varied in format and typically contained multiple codes (4.08 ± 1.77 subthemes), indicating that students participated meaningfully in the assignment. CONCLUSIONS: Although some educators may hesitate to address these topics, students at our institution appreciated having a space to process their thoughts. This assignment structure is an effective way for educators to address a difficult, sensitive, and important topic in a meaningful way with students.


Assuntos
Atitude do Pessoal de Saúde , Educação de Graduação em Medicina , Estudantes de Medicina , Humanos , Estudantes de Medicina/psicologia , Feminino , Masculino , Pigmentação da Pele , Racismo , Adulto , Wisconsin , Competência Cultural , Estados Unidos
2.
J Pediatr Hematol Oncol ; 46(2): e131-e136, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38132672

RESUMO

Mexican and Hispanic children in Mexico and the United States, respectively, have the highest incidence and worst outcomes of pre-B acute lymphoblastic leukemia (ALL) compared with other racial/ethnic groups. Terminal deoxynucleotidyl transferase (TdT) is an intranuclear DNA polymerase normally present on immature lymphocytes (TdT-positive) and distinguishes ALL from mature lymphoid malignancies. We performed a multisite retrospective study to determine the incidence of TdT-negative precursor B-cell acute lymphoblastic leukemia (pre-B ALL) among Mexican, Caucasian, and US-born Hispanic children to correlate TdT expression with patient characteristics and known prognostic factors. Fisher exact test was performed for categorical variables and the Wilcoxon rank-sum test was used for continuous variables. TdT-negative pre-B ALL was most frequently identified in patients with National Cancer Institute high-risk disease ( P =0.014). TdT-negative expression was also most frequently associated with hypodiploid pre-B ALL ( P =0.001) and KMT2A gene rearrangement ( P =0.0012). Mexican children had the highest incidence of TdT-negative ALL compared with Caucasians and US Hispanics ( P <0.001), with an increased incidence of poor prognostic features as well. This study demonstrates significant differences in TdT-negative expression, genomic alterations, and leukemic ploidy based on race and ethnicity.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia , Prognóstico , Estudos Retrospectivos , México/epidemiologia , Incidência , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , DNA Nucleotidilexotransferase/metabolismo , Doença Aguda
3.
Methods Mol Biol ; 2706: 97-124, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37558944

RESUMO

Kinases represent one of the most therapeutically tractable targets for drug discovery in the twenty-first century. However, confirming engagement and achieving intracellular kinase selectivity for small-molecule kinase inhibitors can represent noteworthy challenges. The NanoBRETTM platform enables broad-spectrum live-cell kinase selectivity profiling in most laboratory settings, without advanced instrumentation or expertise. However, the prototype workflow for this selectivity profiling is currently limited to manual liquid handling and 96-well plates. Herein, we describe a scalable workflow with automation and acoustic dispensing, thus dramatically improving the throughput. Such adaptations enable profiling of larger compound sets against 192 full-length protein kinases in live cells, with statistical robustness supporting quantitative analysis.


Assuntos
Ensaios de Triagem em Larga Escala , Proteínas Quinases , Proteínas Quinases/metabolismo , Descoberta de Drogas
4.
Cureus ; 14(10): e30413, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36407215

RESUMO

Introduction The virtual fracture clinic (VFC) can be an effective means of managing specific musculoskeletal injuries, including through protocol-driven direct discharge from the emergency department (ED) or minor injury unit (MIU). This study aimed to measure the efficiency of the VFC triage process while quantifying patient satisfaction after direct discharge from the VFC without routine face-to-face review. Methods We conducted a retrospective analysis of a prospectively collected database to ascertain VFC outcomes for 9064 patients from February 2017 to July 2018. We analysed consultant variation in VFC review and the mean time taken per patient. Patient satisfaction was investigated in 100 chronological patients initially managed via the VFC. Results The mean time to triage each patient was 74 seconds, and a mean of 503 patients was triaged each month. The telephone helpline received a mean of 0.9 calls per week. Seventy-seven percent of patients stated they were happy to be managed without a fracture clinic appointment, and 82% of patients received virtual leaflets in the ED or MIU as per protocol. The number of fracture clinic appointments was reduced by 24% as patients were discharged directly or seen instead by allied health professionals. The median patient satisfaction with VFC management was 90%, and the mean satisfaction with VFC communication was 80%. Conclusion Virtual review of fracture clinic referral enables stratification of patients according to clinical urgency and saves patients from attending unnecessary appointments. This is achieved in a patient population generally satisfied with their overall management. Our study results support the growing trend of VFCs as pivotal systems in streamlining the care of musculoskeletal injuries while adhering to British Orthopaedic Association Standards for Trauma guidelines for Fracture Clinic Services.

5.
Injury ; 53(7): 2605-2616, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35595550

RESUMO

BACKGROUND: The use of bone cement for implant fixation in the surgical management of intracapsular hip fractures (IHFs) remains controversial. Although UK national guidance supports cementation, many surgeons remain cautious of its use. In this systematic review and meta-analysis, we aimed to evaluate evidence surrounding post-operative mortality associated with cemented and uncemented total hip replacement and hemiarthroplasty implants. METHODS: We conducted a search of MEDLINE and Embase databases for randomised controlled trials (RCTs) from commencement until 17 June 2020. Articles reporting mortality or patient survival as an outcome following total hip replacement (THR) or hemiarthroplasty (HA) to manage IHFs were included. Articles not comparing cemented and uncemented fixation were excluded. A meta-analysis on mortality stratified by post-operative follow-up period was conducted using a fixed-effects model. The Revised Cochrane risk-of-bias tool for randomized trials was used to assess risk of bias. RESULTS: Our initial search found 77 references, 13 of which were eligible for full-text review. Mortality data from 12 studies were pooled and included in the meta-analysis. 1 599 operations were reported: 882 involved cemented fixation; 717, uncemented. Mortality outcome reporting ranged from less than 7 days to 5 years post-operation. No significant difference was observed between the two groups in mortality at any follow-up period. Study quality assessment revealed low certainty in mortality estimates. CONCLUSION: Existing evidence indicates that cementation has no effect on mortality at any reported follow-up time period. Even with the use of evidence synthesis, the sample size remains relatively low for mortality outcomes and insufficiently powered to reliably determine differences between groups.


Assuntos
Artroplastia de Quadril , Fraturas do Colo Femoral , Hemiartroplastia , Fraturas do Quadril , Prótese de Quadril , Cimentos Ósseos , Cimentação , Fraturas do Colo Femoral/cirurgia , Fraturas do Quadril/cirurgia , Humanos , Resultado do Tratamento
6.
J Clin Apher ; 37(4): 367-375, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35405029

RESUMO

INTRODUCTION: Therapeutic plasma exchange (TPE) has well-documented applications in the adult population, outlined by the American Society for Apheresis (ASFA) 2019 guidelines. Limited data exist regarding the use of TPE in critically ill pediatric patients; however, these reports rarely include patients with oncological diseases. METHODS: We highlight the use of TPE in the acute management of seven pediatric patients with leukemia treated at Children's Mercy Hospital ICU from 2015 to 2020, including TPE specifications, baseline and interval laboratory evaluation, and outcome measures. Analysis compared those who did (n = 4) and did not (n = 3) survive 30 days post-TPE. RESULTS: Multiorgan failure (MOF) prompted the initiation of TPE in 85.7% of patients, 57.1% of whom were also diagnosed with hemophagocytic lymphohistiocytosis (HLH). Baseline laboratory evaluations prior to initiation of TPE were similar between the two groups. With subsequent TPE treatments, C-reactive protein (CRP) and lactic acid decreased. CRP and lactic acid following the last TPE treatment were significantly higher for those deceased 30 days post-TPE (P = .023 and .031, respectively). No TPE-associated adverse events necessitated discontinuation of TPE treatment. Several surviving patients required chemotherapy dose reductions or alterations. CONCLUSION: Our cohort demonstrated MOF and HLH consistently as indications for TPE, currently ASFA category III indications (optimal role of apheresis is not yet established). Recognition of this treatment modality earlier in the clinical course for critically ill oncological patients may lead to the development of formal protocols that may result in earlier initiation of TPE and improved outcomes.


Assuntos
Remoção de Componentes Sanguíneos , Leucemia , Adulto , Criança , Estado Terminal/terapia , Humanos , Ácido Láctico , Leucemia/complicações , Leucemia/terapia , Insuficiência de Múltiplos Órgãos/etiologia , Insuficiência de Múltiplos Órgãos/terapia , Troca Plasmática/métodos , Estudos Retrospectivos
7.
Bone Joint J ; 102-B(9): 1113-1121, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32862675

RESUMO

AIMS: We conducted a systematic review and meta-analysis to compare the mortality, morbidity, and functional outcomes of cemented versus uncemented hemiarthroplasty in the treatment of intracapsular hip fractures, analyzing contemporary and non-contemporary implants separately. METHODS: PubMed, Medline, EMBASE, CINAHL, and Cochrane Library were searched to 2 February 2020 for randomized controlled trials (RCTs) comparing the primary outcome, mortality, and secondary outcomes of function, quality of life, reoperation, postoperative complications, perioperative outcomes, pain, and length of hospital stay. Relative risks (RRs) and mean differences (with 95% confidence intervals (CIs)) were used as summary association measures. RESULTS: A total of 18 studies corresponding to 16 non-overlapping RCTs with a total of 2,819 intracapsular hip fractures were included. Comparing contemporary cemented versus uncemented hemiarthroplasty, RRs (95% CIs) for mortality were 1.32 (0.44 to 3.99) perioperatively, 1.01 (0.48 to 2.10) at 30 days, and 0.90 (0.71 to 1.15) at one year. The use of contemporary cemented hemiarthroplasty reduced the risk of intra- and postoperative periprosthetic fracture. There were no significant differences in the risk of other complications, function, pain, and quality of life. There were no significant differences in perioperative outcomes except for increases in operating time and overall anaesthesia for contemporary cemented hemiarthroplasty with mean differences (95% CIs) of 6.67 (2.65 to 10.68) and 4.90 (2.02 to 7.78) minutes, respectively. The morbidity and mortality outcomes were not significantly different between non-contemporary cemented and uncemented hemiarthroplasty. CONCLUSION: There are no differences in the risk of mortality when comparing the use of contemporary cemented with uncemented hemiarthroplasty in the management of intracapsular hip fractures. Contemporary cemented hemiarthroplasty is associated with a substantially lower risk of intraoperative and periprosthetic fractures. Cite this article: Bone Joint J 2020;102-B(9):1113-1121.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia de Quadril/métodos , Cimentos Ósseos , Hemiartroplastia/efeitos adversos , Fraturas do Quadril/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Humanos , Complicações Pós-Operatórias/mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Resultado do Tratamento
8.
Pediatr Blood Cancer ; 67(9): e28331, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32667140

RESUMO

BACKGROUND: The objective was to investigate factors associated with patient-related timing (PRT) to seek healthcare and health service-related timing (HSRT) to diagnose cancer and provide treatment to children without social security in Mexico. PROCEDURE: A cross-sectional survey was conducted in 13 Ministry of Health hospitals in the states of Chihuahua, Jalisco, Mexico City, Morelos, Oaxaca, Puebla, Queretaro, State of Mexico, and Tlaxcala. Study participants were parents of recently diagnosed pediatric cancer patients (≤ 17 years of age). Three groups of factors were investigated: (1) patients (child and parent characteristics); (2) healthcare providers (HCPs) (first-contact HCP, institution, perceptions of barriers to healthcare, etc.); and (3) disease factors (cancer type/site, stage/risk at diagnosis). PRT and HSRT-associated factors were identified using multiple negative binomial regressions. RESULTS: The study included 265 children; 49% sought care when symptoms first appeared. The median PRT was seven days, and the median HSRT was 40 days. Parents' perceptions of long wait times for appointments were associated with longer PRT and HSRT. Residing in the lowest or highest socioeconomic regions and persistent or worsening symptoms increased the probability of longer PRT. Older patient age, HCP requests for imaging tests or prescription for steroids, a higher number of doctors consulted, having a urinary tract cancer, and having an advanced stage or high-risk cancer increased the probability of longer HSRT. CONCLUSION: Strategies to shorten lag time from symptom onset to diagnosis and treatment are urgently needed for childhood cancers in Mexico.


Assuntos
Atenção à Saúde/estatística & dados numéricos , Neoplasias/terapia , Previdência Social/estatística & dados numéricos , Tempo para o Tratamento/estatística & dados numéricos , Populações Vulneráveis/estatística & dados numéricos , Criança , Pré-Escolar , Estudos Transversais , Feminino , Pessoal de Saúde , Serviços de Saúde/estatística & dados numéricos , Humanos , Masculino , México , Neoplasias/diagnóstico , Pais/psicologia , Fatores Socioeconômicos
9.
Cureus ; 11(6): e4877, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31417822

RESUMO

OBJECTIVES: Surgeons require high-quality surgical instruments to carry out successful procedures. Poor quality instruments may break intraoperatively leading to a failed procedure or causing harm to the patient. By examining the National Reporting and Learning Service (NRLS) database, the study aims to define the scale of the problem and provide evidence for the formation of surgical instrument quality control. METHODS: The NRLS was searched from August 2004 - December 2010. The search revealed 2036 incidents, 250 of which were randomly selected and analyzed by a clinical reviewer. RESULTS: One hundred and sixty-one incidents were identified causing five reoperations, one incident of severe harm, six incidents of moderate harm, 35 of low harm, and 119 no harm incidents. No patient deaths were discovered. Drillbits were the most commonly broken instrument. CONCLUSIONS: This report is likely to only be the tip of the iceberg. Poor reporting of patient safety incidents means that there may be as many as 1500 incidents a year of poor quality surgical instruments causing harm. We suggest that forming a Surgical Instrument Quality Service at Trusts within the National Health Service (NHS) could prevent harm coming to patients, reduce cost, and improve the outcomes of surgical procedures.

10.
Cureus ; 11(5): e4642, 2019 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-31312568

RESUMO

INTRODUCTION:  Medical students across the United Kingdom (UK) report poor satisfaction with surgical teaching. The Surgical Skills Day (SSD) begins to address this by exposing medical students to surgery through an easily accessible one-day practical workshop. This study shows how the SSD encourages undergraduate engagement in surgery. METHOD:  Feedback forms were emailed to attendees of the SSD and their anonymised responses were used to evaluate the SSD. RESULTS:  A total of 144 students attended the SSD across three years and the feedback response rate was 74% (n = 107). Key findings were that 100% of respondents (n = 107) would like the SSD to be an annual event, 79% (n = 83) were more inclined to pursue a surgical career following the event, and 97% (n = 103) would like to see practical surgical skills incorporated into the curriculum. The SSD was able to engage undergraduates with surgery through mentorship, practical skills, specialty exposure, and teaching of the General Medical Council (GMC) mandated skills. CONCLUSIONS:  Undergraduate surgical teaching in the UK is insufficient. The student-led annual SSD showed improved engagement in practical surgical skills and increased enthusiasm for a surgical career. In light of this, the authors feel the SSD or similar event should be integrated into the UK medical school curriculum.

11.
J Electrocardiol ; 52: 109-111, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30551061

RESUMO

Lyme disease is the most common tick-borne illness in North America. A 23-year-old female presented to our emergency department with a chief complaint of sudden dyspnea and chest pain. An electrocardiogram revealed a third degree heart block. She was a resident of the Northeast region of Mexico and referred a recent travel to an endemic area for Borrelia burgdorferi in the center of Mexico in the past weeks. Lyme carditis was diagnosed after enzyme linked immunosorbent assay for IgM antibodies against B. burgdorferi was reported positive and corroborated by a confirmatory immunoblot analysis. Persistent AV block was the only manifestation in our patient, a presentation scarcely reported in literature.


Assuntos
Bloqueio Atrioventricular/diagnóstico , Bradicardia/diagnóstico , Doença de Lyme/diagnóstico , Antibacterianos/uso terapêutico , Bloqueio Atrioventricular/fisiopatologia , Bloqueio Atrioventricular/terapia , Bradicardia/fisiopatologia , Bradicardia/terapia , Diagnóstico Diferencial , Eletrocardiografia , Feminino , Humanos , Doença de Lyme/tratamento farmacológico , Doença de Lyme/fisiopatologia , Marca-Passo Artificial , Adulto Jovem
13.
New Dir Child Adolesc Dev ; 2018(160): 75-87, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29633538

RESUMO

This article considers how the global "academic pipeline problem" constrains immigrant, low-income, and ethnic minority students' pathways to higher education, and how some students build pathways to college and career identities. After aligning theories of social capital, alienation/belonging, and challenge and their integration in Bridging Multiple Worlds Theory, we summarize six longitudinal studies based on this theory from a 23-year university-community partnership serving low-income, primarily U.S. Mexican immigrant youth. Spanning from childhood to early adulthood, the studies revealed two overarching findings: First, students built pathways to college and career identities while experiencing capital, alienation/belonging, and challenges across their evolving cultural worlds. Second, by "giving back" to families, peers, schools, and communities, students became cultural brokers and later, institutional agents, transforming institutional cultures. Findings highlight the value of integrating interdisciplinary theories, research evidence, and educational systems serving diverse communities to open individual pathways and academic pipelines in multicultural societies.


Assuntos
Escolha da Profissão , Emigrantes e Imigrantes/psicologia , Americanos Mexicanos/psicologia , Alienação Social/psicologia , Capital Social , Identificação Social , Estudantes/psicologia , Universidades , Adolescente , Adulto , Criança , Humanos , México/etnologia , Estados Unidos/etnologia , Adulto Jovem
15.
Patholog Res Int ; 2015: 132326, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26634172

RESUMO

The prognostic role of N-glycolyl GM3 ganglioside (NeuGcGM3) expression in non-small cell lung carcinoma (NSCLC) still remains controversial. In this study, the NeuGcGM3 expression was reevaluated using an increased number of NSCLC cases and the 14F7 Mab (a highly specific IgG1 raised against NeuGcGM3). An immunohistochemical score integrating the percentage of 14F7-positive cells and the intensity of reaction was applied to reassess the relationship between NeuGcGM3 expression, some clinicopathological features, and the overall survival (OS) of NSCLC patients. The double and the triple expression of NeuGcGM3 with the epidermal growth factor receptor (EGFR) and/or its ligand, the epidermal growth factor (EGF), were also evaluated. NeuGcGM3 expression correlates with both S-Phase fraction (p = 0.006) and proliferation index (p = 0.000). Additionally, NeuGcGM3 expression was associated with a poor OS of patients in both univariate (p = 0.020) and multivariate (p = 0.010) analysis. Moreover, the double and/or the triple positivity of tumors to NeuGcGM3, EGFR, and/or EGF permitted us to identify phenotypes of NSCLC with a more aggressive biological behavior. Our results are in agreement with the negative prognostic significance of NeuGcGM3 expression in NSCLC patients. However, standardization of techniques to determine the expression of NeuGcGM3 in NSCLC as well as the implementation of a universal scoring system is recommended.

16.
FEMS Microbiol Ecol ; 66(2): 401-10, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18717738

RESUMO

Arsenic oxidation is recognized as being mediated by both heterotrophic and chemoautotrophic microorganisms. Enrichment cultures were established to determine whether chemoautotrophic microorganisms capable of oxidizing arsenite As(III) to arsenate As(V) are present in selected contaminated but nonextreme environments. Three new organisms, designated as strains OL-1, S-1 and CL-3, were isolated and found to oxidize 10 mM arsenite to arsenate under aerobic conditions using CO2-bicarbonate (CO2/HCO3-) as a carbon source. Based on 16S rRNA gene sequence analyses, strain OL-1 was 99% most closely related to the genus Ancylobacter, strain S-1 was 99% related to Thiobacillus and strain CL-3 was 98% related to the genus Hydrogenophaga. The isolates are facultative autotrophs and growth of isolated strains on different inorganic electron donors other than arsenite showed that all three had a strong preference for several sulfur species, while CL-3 was also able to grow on ammonium and nitrite. The RuBisCO Type I (cbbL) gene was positively amplified and sequenced in strain CL-3, and the Type II (cbbM) gene was detected in strains OL-1 and S-1, supporting the autotrophic nature of the organisms.


Assuntos
Arsenitos/metabolismo , Processos Autotróficos , Sedimentos Geológicos/microbiologia , Proteobactérias/classificação , Microbiologia do Solo , Meios de Cultura , DNA Bacteriano/análise , DNA Bacteriano/isolamento & purificação , Genes de RNAr , Dados de Sequência Molecular , Oxirredução , Filogenia , Proteobactérias/crescimento & desenvolvimento , Proteobactérias/isolamento & purificação , Proteobactérias/metabolismo , RNA Ribossômico 16S/genética , Ribulose-Bifosfato Carboxilase/genética , Ribulose-Bifosfato Carboxilase/metabolismo , Análise de Sequência de DNA
18.
Environ Sci Technol ; 39(24): 9569-73, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16475337

RESUMO

Naturally occurring arsenic is found predominantly as arsenate [As(V)] or arsenite [As(III)], and can be readily oxidized or reduced by microorganisms. Given the health risks associated with arsenic in groundwater and the interest in arsenic-active microorganisms, we hypothesized that environmental microorganisms could mediate a redox cycling of arsenic that is linked to their metabolism. This hypothesis was tested using an As(V) respiring reducer (strain Y5) and an aerobic chemoautotrophic As(II) oxidizer (strain OL1 ) both isolated from a Superfund site, Onondaga Lake, in Syracuse, NY. Strains were grown separately and together in sealed serum bottles, and the oxic/anoxic condition was the only parameter changed. Initially, under anoxic conditions when both isolates were grown together, 2 mM As(V) was stoichiometrically reduced to As(III) within 14 days. Following complete reduction, sterile ambient air was added and within 24 h As(III) was completely oxidized to As(V). The anoxic-oxic cycle was repeated, and sterile controls showed no abiotic transformation within the 28-day incubation period. These results demonstrate that microorganisms can cycle arsenic in response to dynamic environmental conditions, thereby affecting the speciation, and hence mobility and toxicity of arsenic in the environment.


Assuntos
Arsênio/metabolismo , Ecossistema , Microbiologia do Solo , Microbiologia da Água , Poluentes Químicos da Água/metabolismo , Anaerobiose , Arseniatos/metabolismo , Arsenitos/metabolismo , Hipóxia/metabolismo , New York , Oxirredução , Fatores de Tempo , Poluentes Químicos da Água/toxicidade
19.
FEMS Microbiol Ecol ; 48(3): 323-32, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-19712302

RESUMO

A novel anaerobic bacterium was isolated from the sediment of Onondaga Lake (Syracuse, NY), which can use arsenate [As(V)] as a respiratory electron acceptor. The isolate, designated strain Y5 is a spore-forming, motile rod, with lateral flagella. It is Gram-negative though it phylogenetically falls within the low G + C Gram-positive organisms. In addition to the more usual electron donors such as lactate and succinate, strain Y5 also can use H(2)+ CO(2) chemoautotrophically and metabolize aromatic compounds such as syringic acid, ferulic acid, phenol, benzoate and toluene, coupled to arsenate reduction. Aside from As(V), nitrate, sulfate, thiosulfate and Fe(III) can also serve as electron acceptors. Based on 16S rDNA phylogeny and its physiological characteristics, strain Y5 was identified as most closely related to the genus Desulfosporosinus. The ability of microorganisms to reduce arsenate for respiration appears to be widely distributed and may be relevant in the biogeochemical cycling of arsenic in environments containing mixed contaminants.


Assuntos
Arseniatos/metabolismo , Hidrocarbonetos Aromáticos/metabolismo , Peptococcaceae/classificação , Peptococcaceae/metabolismo , Anaerobiose , Dióxido de Carbono/metabolismo , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Água Doce/microbiologia , Hidrogênio/metabolismo , Dados de Sequência Molecular , New York , Nitratos/metabolismo , Oxirredução , Peptococcaceae/isolamento & purificação , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Sulfatos/metabolismo , Tiossulfatos/metabolismo
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