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2.
Isr J Health Policy Res ; 12(1): 16, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-37098565

RESUMO

BACKGROUND: Maternal CMV infection during pregnancy, either primary or non-primary, may be associated with fetal infection and long-term sequelae. While guidelines recommend against it, screening for CMV in pregnant women is a prevalent clinical practice in Israel. Our aim is to provide updated, local, clinically relevant, epidemiological information about CMV seroprevalence among women at childbearing age, the incidence of maternal CMV infection during pregnancy and the prevalence of congenital CMV (cCMV), as well as to provide information about the yield of CMV serology testing. METHODS: We performed a descriptive, retrospective study of women at childbearing age who were members of Clalit Health Services in the district of Jerusalem and had at least one gestation during the study period (2013-2019). We utilized serial serology tests to determine CMV serostatus at baseline and at pre/periconception and identified temporal changes in CMV serostatus. We then conducted a sub-sample analysis integrating inpatient data on newborns of women who gave birth in a single large medical center. cCMV was defined as either positive urine CMV-PCR test in a sample collected during the first 3 weeks of life, neonatal diagnosis of cCMV in the medical records, or prescription of valganciclovir during the neonatal period. RESULTS: The study population Included 45,634 women with 84,110 associated gestational events. Initial CMV serostatus was positive in 89% women, with variation across different ethno-socioeconomic subgroups. Based on consecutive serology tests, the detected incidence rate of CMV infection was 2/1000 women follow-up years, among initially seropositive women, and 80/1000 women follow-up years, among initially seronegative women. CMV infection in pregnancy was identified among 0.2% of women who were seropositive at pre/periconception and among 10% of women who were seronegative. In a subsample, which included 31,191 associated gestational events, we identified 54 newborns with cCMV (1.9/1000 live births). The prevalence of cCMV among newborns of women who were seropositive at pre/periconception was lower than among newborns of women who were seronegative (2.1 vs. 7.1/1000). Frequent serology tests among women who were seronegative at pre/periconception detected most primary CMV infections in pregnancy that resulted in cCMV (21/24). However, among women who were seropositive, serology tests prior to birth detected none of the non-primary infections that resulted in cCMV (0/30). CONCLUSIONS: In this retrospective community-based study among women of childbearing age characterized by multiparity and high seroprevalence of CMV, we find that consecutive CMV serology testing enabled to detect most primary CMV infections in pregnancy that led to cCMV in newborns but failed to detect non-primary CMV infections in pregnancy. Conducting CMV serology tests among seropositive women, despite guidelines' recommendations, has no clinical value, while it is costly and introduces further uncertainties and distress. We thus recommend against routine CMV serology testing among women who were seropositive in a prior serology test. We recommend CMV serology testing prior to pregnancy only among women known to be seronegative or women whose serology status is unknown.


Assuntos
Infecções por Citomegalovirus , Citomegalovirus , Feminino , Humanos , Recém-Nascido , Gravidez , Masculino , Estudos Retrospectivos , Estudos Soroepidemiológicos , Idade Materna , Israel/epidemiologia , Infecções por Citomegalovirus/diagnóstico , Infecções por Citomegalovirus/epidemiologia
3.
Sci Rep ; 11(1): 22777, 2021 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-34815503

RESUMO

New Coronavirus Disease 2019 (COVID-19) vaccines are available to prevent the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. We compared the efficacy of new COVID-19 vaccines to prevent symptomatic and severe disease in the adult population and to prevent symptomatic COVID-19 among the elderly. Leading medical databases were searched until August 30, 2021. Published phase 3 randomized controlled trials (RCTs) evaluated efficacy of the vaccine to prevent symptomatic and sever COVID-19 in adults were included. Two reviewers independently evaluated the literature search results and independently extracted summary data. The risk of bias was evaluated using the Cochrane Risk of Bias Assessment Tool. We performed a network meta-analysis (NMA) according to PRISMA-NMA 2015 to pool indirect comparisons between different vaccines regarding their relative efficacy. The primary outcomes were the efficacy of the vaccine against symptomatic COVID-19 in adults (PROSPERO registration number: CRD42021235364). Above 200,000 adult participants from eight phase 3 RCTs were included in NMA, of whom 52% received the intervention (active COVID-19 vaccine). While each of nine vaccines was tested in the unique clinical trial as compared to control, based on indirect comparison, BNT162b2 and mRNA-1273 vaccines were ranked with the highest probability of efficacy against symptomatic COVID-19 (P-scores 0.952 and 0.843, respectively), followed by Gam-COVID-Vac (P-score 0.782), NVX-CoV23730 (P-score 0.700), CoronaVac (P-score 0.570), BN02 (P-score 0.428), WIV04 (P-score 0.327), and Ad26.COV2.S (P-score 0.198). No statistically significant difference was seen in the ability of the vaccines to prevent symptomatic disease in the elderly population. No vaccine was statistically significantly associated with a decreased risk for severe COVID-19 than other vaccines, although mRNA-1273 and Gam-COVID-Vac have the highest P-scores (0.899 and 0.816, respectively), indicating greater protection against severe disease than other vaccines. In our indirect comparison, the BNT162b2 and mRNA-1273 vaccines, which use mRNA technology, were associated with the highest efficacy to prevent symptomatic COVID-19 compared to other vaccines. This finding may have importance when deciding which vaccine to use, together with other important factors as availability of the vaccines, costs, logistics, side effects, and patient acceptability.


Assuntos
Vacinas contra COVID-19/farmacologia , COVID-19/prevenção & controle , SARS-CoV-2/efeitos dos fármacos , Biometria , COVID-19/epidemiologia , Humanos , Metanálise em Rede , Pandemias , SARS-CoV-2/patogenicidade , Resultado do Tratamento , Vacinas
4.
N Engl J Med ; 385(23): 2140-2149, 2021 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-34614328

RESUMO

BACKGROUND: Approximately 5.1 million Israelis had been fully immunized against coronavirus disease 2019 (Covid-19) after receiving two doses of the BNT162b2 messenger RNA vaccine (Pfizer-BioNTech) by May 31, 2021. After early reports of myocarditis during adverse events monitoring, the Israeli Ministry of Health initiated active surveillance. METHODS: We retrospectively reviewed data obtained from December 20, 2020, to May 31, 2021, regarding all cases of myocarditis and categorized the information using the Brighton Collaboration definition. We analyzed the occurrence of myocarditis by computing the risk difference for the comparison of the incidence after the first and second vaccine doses (21 days apart); by calculating the standardized incidence ratio of the observed-to-expected incidence within 21 days after the first dose and 30 days after the second dose, independent of certainty of diagnosis; and by calculating the rate ratio 30 days after the second dose as compared with unvaccinated persons. RESULTS: Among 304 persons with symptoms of myocarditis, 21 had received an alternative diagnosis. Of the remaining 283 cases, 142 occurred after receipt of the BNT162b2 vaccine; of these cases, 136 diagnoses were definitive or probable. The clinical presentation was judged to be mild in 129 recipients (95%); one fulminant case was fatal. The overall risk difference between the first and second doses was 1.76 per 100,000 persons (95% confidence interval [CI], 1.33 to 2.19), with the largest difference among male recipients between the ages of 16 and 19 years (difference, 13.73 per 100,000 persons; 95% CI, 8.11 to 19.46). As compared with the expected incidence based on historical data, the standardized incidence ratio was 5.34 (95% CI, 4.48 to 6.40) and was highest after the second dose in male recipients between the ages of 16 and 19 years (13.60; 95% CI, 9.30 to 19.20). The rate ratio 30 days after the second vaccine dose in fully vaccinated recipients, as compared with unvaccinated persons, was 2.35 (95% CI, 1.10 to 5.02); the rate ratio was again highest in male recipients between the ages of 16 and 19 years (8.96; 95% CI, 4.50 to 17.83), with a ratio of 1 in 6637. CONCLUSIONS: The incidence of myocarditis, although low, increased after the receipt of the BNT162b2 vaccine, particularly after the second dose among young male recipients. The clinical presentation of myocarditis after vaccination was usually mild.


Assuntos
Vacina BNT162/efeitos adversos , COVID-19/prevenção & controle , Miocardite/etiologia , Adolescente , Adulto , Distribuição por Idade , Comorbidade , Ecocardiografia , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Incidência , Israel/epidemiologia , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Miocardite/epidemiologia , Gravidade do Paciente , Estudos Retrospectivos , Distribuição por Sexo , Adulto Jovem
5.
Euro Surveill ; 25(29)2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32720636

RESUMO

On 13 March 2020, Israel's government declared closure of all schools. Schools fully reopened on 17 May 2020. Ten days later, a major outbreak of coronavirus disease (COVID-19) occurred in a high school. The first case was registered on 26 May, the second on 27 May. They were not epidemiologically linked. Testing of the complete school community revealed 153 students (attack rate: 13.2%) and 25 staff members (attack rate: 16.6%) who were COVID-19 positive.


Assuntos
Infecções por Coronavirus/epidemiologia , Coronavirus , Pneumonia Viral/epidemiologia , Instituições Acadêmicas , Estudantes/estatística & dados numéricos , Adolescente , Adulto , Betacoronavirus , COVID-19 , Criança , Infecções por Coronavirus/diagnóstico , Surtos de Doenças , Feminino , Humanos , Incidência , Israel/epidemiologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/diagnóstico , SARS-CoV-2
6.
Euro Surveill ; 23(38)2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30255835

RESUMO

We report preliminary findings of a large outbreak of human leptospirosis with 36 confirmed/probable and 583 suspected cases from June-August 2018, linked to contaminated water bodies in Northern Israel. There was a travel-associated case in Germany; additional cases are being investigated in other countries. The presumed chain of transmission, implicating wild boar and cattle, raises multiple challenges for risk assessment, risk management and risk communication currently being addressed by a public health response team.


Assuntos
Surtos de Doenças , Leptospira/classificação , Leptospirose/epidemiologia , Poluição da Água/efeitos adversos , Animais , Bovinos , Epidemias , Feminino , Alemanha , Humanos , Israel/epidemiologia , Leptospirose/diagnóstico , Leptospirose/transmissão , Saúde Pública , Gestão de Riscos , Suínos , Viagem , Microbiologia da Água
7.
Biomed Res Int ; 2014: 135416, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25013756

RESUMO

Congenital cytomegalovirus (CMV) is the leading infectious cause of sensorineural hearing loss and delayed psychomotor development. Viral transmission to the fetus is far more likely to occur following a primary than a secondary maternal infection. Primary prevention seems to be the best means to reduce the burden of congenital CMV due to the lack of treatment options during pregnancy. We evaluated this approach on a cohort of 500 women planning pregnancy who attended our fertility clinic. Of the 444 who underwent CMV screening, 18 (4.1%) had positive IgM serology for CMV; of these, IgG avidity was high in 12 (remote infection) and low in 6 (recent infection). The latter were advised to delay pregnancy. All women who were seroimmune for CMV (366/444, 82.4%), including the 12 with remote infection, continued fertility treatment. The remaining patients (72/444, 16.2%), who were not immune to CMV at the initial screen, were advised to minimize CMV exposure by improving personal hygiene and to continue fertility treatment. None of the 69/72 (95.8%) women who were followed for one year were infected with CMV. Cytomegalovirus testing and counselling at preconception seemed effective in reducing CMV exposure in pregnancy.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Citomegalovirus/sangue , Citomegalovirus/isolamento & purificação , Diagnóstico Pré-Natal , Adulto , Citomegalovirus/imunologia , Citomegalovirus/patogenicidade , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Feminino , Feto/imunologia , Feto/virologia , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Neurossensorial/virologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Gravidez , Transtornos Psicomotores/diagnóstico , Transtornos Psicomotores/virologia
9.
Isr Med Assoc J ; 13(6): 325-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21809726

RESUMO

BACKGROUND: Influenza vaccination of community-dwelling elderly is widely recommended. Observational studies have shown a strong association between physicians' personal vaccination status and their reported level of recommendation to patients and possibly their patients' actual vaccination. No published trials have examined whether increasing vaccination rates of primary care staff raises vaccination among their patients. Proof of a positive effect would support the notion that vaccinating health care workers benefits their patients. OBJECTIVES: To examine whether an intervention to increase staff vaccination also increases vaccination of their patients aged 65 and over. METHODS: A trial examining an intervention aiming to raise staff immunization rates was performed in primary care community clinics in the Jerusalem area. The study population comprised the staff of 13 randomly chosen intervention clinics during the season of 2007-2008, with another 14 clinics serving as controls. The intervention resulted in a staff vaccination rate of 52.8% compared to 26.5% in the control clinics (66.1% and 32.2% among physicians). No intervention was directed at the patients. Data on patient vaccination and other patient characteristics were extracted from the health funds' computerized databases. RESULTS: The percentage of patients vaccinated during the intervention season was 57.8% in both intervention and control groups, reflecting an increase of 14.4% compared to the previous season in the intervention clinics and of 13.4% in the control clinics. Logistic regression demonstrated a statistically significant association between intervention and patient vaccination with an odds ratio of 1.10 (95% confidence interval 1.03-1.18). However, analysis adjusting for clustering did not show a significant association. CONCLUSIONS: Increasing influenza vaccination of the medical staff did not substantially increase patient vaccination. These results do not show any patient benefit from staff vaccination in primary care.


Assuntos
Serviços de Saúde Comunitária , Vacinas contra Influenza/administração & dosagem , Influenza Humana/prevenção & controle , Atenção Primária à Saúde , Vacinação/estatística & dados numéricos , Idoso , Feminino , Seguimentos , Humanos , Incidência , Influenza Humana/epidemiologia , Israel/epidemiologia , Masculino , Estudos Retrospectivos
11.
Prehosp Disaster Med ; 26(5): 386-90, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22281092

RESUMO

INTRODUCTION: Mass-casualty triage is implemented when available resources are insufficient to meet the needs of all patients in a disaster situation. The basic principle is to do the maximum good for the most casualties with the least amount of resources. There are limited data to support the applicability of this principle in massive disasters such as the January 2010 earthquake in Haiti, in which the number of patients seeking medical attention overwhelmed the local resources. OBJECTIVE: To analyze the application of a triage system developed for use in a mass-casualty setting with limited resources. The system was designed to admit only those patients who had medical conditions requiring urgent treatment that were within the capabilities of the hospital and had a good chance of survival after discharge. Priority was given to those whose treatment could be administered within a short hospital stay. METHOD: A retrospective, observational review of computerized registration forms of Haitian earthquake victims who sought medical care at a 72-bed field hospital within four to 14 days after the event. An analysis of the efficacy of the triage protocol that was used followed, using length of hospital stay to measure consumption of resources. RESULTS: A total of 1,111 patients were triaged for treatment in the field hospital within 14 days of the earthquake. The median length of stay for all patients for whom data was available was 16 hours (mean = 29.7 hours). The majority of patients (n = 620, 65%) were discharged within 24 hours. Two hundred five patients underwent surgery and were discharged within a median of 39 hours (mean = 52.6 hours); of these, 124 (62%) were discharged within 48 hours. The total mortality of the treated patients was 1.5% (n = 17). CONCLUSIONS: Currently accepted triage principles for the most part are appropriate for efficiently providing medical care in a disaster area with extremely limited resources, but require extensive adaptation to local conditions.


Assuntos
Terremotos , Incidentes com Feridos em Massa , Triagem/estatística & dados numéricos , Haiti , Humanos
14.
Infect Control Hosp Epidemiol ; 31(9): 951-7, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20645864

RESUMO

After the January 12, 2010, earthquake in Haiti, Project Medishare and the University of Miami organized, built, and staffed a 200-bed field hospital (the University of Miami Hospital in Haiti [UMHH]) on the outskirts of Port-au-Prince. We describe the operational challenges of providing a safe environment at the UMHH. Furthermore, we compared how these issues were addressed at this ad hoc hospital with how they were addressed at the field hospital of the Israel Defense Force, a fully deployable hospital with an organization fine-tuned as a result of prior disaster situations, also in Haiti.


Assuntos
Medicina de Desastres/organização & administração , Desastres , Terremotos , Controle de Infecções/organização & administração , Unidades Móveis de Saúde/organização & administração , Socorro em Desastres/organização & administração , Feminino , Haiti , Humanos , Cooperação Internacional , Masculino
15.
Ann Fam Med ; 8(4): 293-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20644183

RESUMO

PURPOSE: Although vaccination of health care workers against influenza is widely recommended, vaccination uptake is low. Data on interventions to increase staff immunization in primary care are lacking. We examine the effect of a promotional and educational intervention program, not addressing vaccine availability, to raise the influenza vaccination rate among staff in primary care clinics. METHODS: The study included all 344 staff members with direct patient contact (physicians, nurses, pharmacists, and administrative and ancillary staff) in 27 primary care community clinics in the Jerusalem area during the 2007-2008 influenza season. Thirteen clinics were randomly selected for an intervention that consisted of a lecture session given by a family physician, e-mail-distributed literature and reminders, and a key figure from the local staff who personally approached each staff member. RESULTS: Influenza immunization rate was 52.8% (86 of 163) in the intervention group compared with 26.5% (48 of 181) in the control group (P<.001). When compared with the rate of immunization for the previous season, the absolute increase in immunization rate was 25.8% in the intervention clinics and 6.6% in the control clinics. Multivariate analysis showed a highly significant (P<.001) independent association between intervention and immunization, with an odds ratio of 3.51 (95% confidence interval, 2.03-6.09). CONCLUSION: We have developed an effective intervention program to increase previously low vaccination rates among primary health care workers. This simple intervention could be reproduced easily in other clinics and organizations with an expected substantial increase in influenza immunization rates.


Assuntos
Vacinas contra Influenza , Influenza Humana/prevenção & controle , Corpo Clínico/organização & administração , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Educação de Pacientes como Assunto , Atenção Primária à Saúde/organização & administração , Adulto , Idoso , Instituições de Assistência Ambulatorial/organização & administração , Intervalos de Confiança , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Sistemas Pré-Pagos de Saúde , Política de Saúde , Humanos , Israel , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Estatística como Assunto , Inquéritos e Questionários , Adulto Jovem
16.
Isr Med Assoc J ; 12(12): 742-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21348402

RESUMO

BACKGROUND: Appropriate antibiotic use is of both clinical and economic significance to any health system and should be given adequate attention. Prior to this study, no in-depth information was available on antibiotic use patterns in the emergency department of Hadassah Medical Center. OBJECTIVES: To describe the use and misuse of antibiotics and their associated costs in the emergency department of Hadassah Medical Center. METHODS: We analyzed the charts of 657 discharged patients and 45 admitted patients who received antibiotics in Hadassah's emergency department during a 6 week period (29 April - 11 June 2007). A prescription was considered appropriate or inappropriate if the choice of antibiotic, dose and duration by the prescribing physician after diagnosis was considered suitable or wrong by the infectious diseases consultant evaluating the prescriptions according to Kunin's criteria. RESULTS: The overall prescribing rate of antibiotics was 14.5% (702/4830) of which 42% were broad-spectrum antibiotics. The evaluated antibiotic prescriptions numbered 1105 (96 prescriptions containing 2 antibiotics, 2 prescriptions containing 3 antibiotics), and 54% of them were considered appropriate. The total inappropriate cost was 3583 NIS (1109 USD PPP) out of the total antibiotic costs of 27,300 NIS (8452 USD PPP). The annual total antibiotic cost was 237,510 NIS (73,532 USD PPP) and the annual total inappropriate cost was 31,172 NIS (9648 USD PPP). The mean costs of inappropriate prescriptions were highest for respiratory (112 NIS, 35 USD PPP) and urinary tract infection (93 NIS, 29 USD PPP). There were more cases when the optimal cost was lower than the actual cost (N = 171) than when optimal cost was higher than the actual cost (N = 9). In the first case, the total inappropriate costs were 3805 NIS (1178 USD PPP), and in the second case, -222 NIS (68.7 USD PPP). CONCLUSIONS: The use of antibiotics in emergency departments should be monitored, especially in severely ill patients who require broad-spectrum antibiotics and for antibiotics otherwise restricted in the hospital wards. Our findings indicate that 12% of the total antibiotic costs could have been avoided if all prescriptions were optimal.


Assuntos
Antibacterianos/economia , Serviço Hospitalar de Emergência/estatística & dados numéricos , Prescrição Inadequada/economia , Antibacterianos/uso terapêutico , Uso de Medicamentos , Fidelidade a Diretrizes , Humanos , Prescrição Inadequada/estatística & dados numéricos , Israel
17.
Environ Sci Technol ; 43(8): 2950-6, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19475976

RESUMO

Sludge age or mean cell residence time (MCRT) plays a crucial role in design and operation of wastewater treatment plants. The change in performance, for example micropollutant removal, associated with changes in MCRT is often attributed to changes in microbial diversity. We operated four identical laboratory-scale sequencing batch reactors (two test and two control) in parallel for 212 days. Sludge age was decreased gradually (from 10.4to 2.6 days) in experimental reactors whereas it was kept constant (10.4 days) in control reactors. The reactor performance and biomass changed in a manner consistent with our understanding of the effect of sludge age on a reactors performance: the effluent quality and biomass declined with decreasing MCRT. The composition of the bacterial and ammonia-oxidizing bacterial communities in four reactors was analyzed using denaturing gradient gel electrophoresis (DGGE), and similarities in band patterns were measured using the Dice coefficient. The overall similarity between the communities in reactors run at different sludge ages was indistinguishable from the similarity in communities in reactors run at identical sludge ages. This was true for both the general bacterial communities and putative AOB communities. The number of detectable bands in DGGE profiles was also unaffected by sludge age (p approximately 0.5 in both cases). Initially, the detectable diversity of activated sludge communities in all four reactors clustered with time, regardless of their designation or sludge age; however, these clusters were only weakly supported by bootstrap analysis. However, after 135 days, a sludge age specific clustering was observed in the bacterial community but not the putative ammonia-oxidizing bacterial community. The mean self-similarity of each reactor decreased, variance increased, and the number of detectable bands in DGGE profiles decreased over time in all reactors. The changes observed with time are consistent with ecological drift. Sludge age has a subtler and slower effect than we anticipated. However, we postulate that sludge age may be more evident in the taxa occurring below the detection limit of DGGE. New sequencing technology may help us address this hypothesis.


Assuntos
Bactérias/classificação , Reatores Biológicos , Esgotos , Bactérias/metabolismo , Eletroforese em Gel de Poliacrilamida , Reação em Cadeia da Polimerase
18.
Environ Microbiol ; 6(7): 669-77, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15186345

RESUMO

Changes in the abundance of sympatric Achromatium spp. in response to the artificial manipulation of redox conditions in sediment microcosms was determined by fluorescence in situ hybridization (FISH). Adaptation to different redox conditions was shown to be one mechanism that supported the coexistence of functionally similar Achromatium spp. In sediment microcosms, in which the overlying water was oxygenated, Achromatium community size and composition remained unchanged over time. However, imposition of anoxic conditions induced changes in community structure. Anoxia caused a reduction in the relative abundance of Achromatium sp. RY8 (72 +/- 4% to 49 +/- 2%) and an increase in Achromatium sp. RY5 (19 +/- 5% to 32 +/- 3%) and a newly identified Achromatium sp., RYKS (14 +/- 4% to 27 +/- 2%). In anoxic microcosms supplemented with a single addition of nitrate at different initial concentrations the relative decline in Achromatium sp. RY8 was dependent on the initial nitrate concentration. In these experiments nitrate was rapidly removed. In contrast, when high levels of nitrate were maintained by periodic replacement of the overlying water with nitrate supplemented anoxic water, the composition of the Achromatium community remained stable over time. This suggested that all of the coexisting Achromatium spp. are obligate or facultative anaerobes, but, Achromatium sp. RY8 was more sensitive to sediment redox conditions than the other Achromatium species. Given the heterogeneous nature of sedimentary environments, redox-related niche differentiation may promote coexistence of sympatric Achromatium spp.


Assuntos
Adaptação Fisiológica , Sedimentos Geológicos/microbiologia , Bactérias Aeróbias Gram-Negativas/crescimento & desenvolvimento , Bactérias Aeróbias Gram-Negativas/metabolismo , Aerobiose , Anaerobiose , Contagem de Colônia Microbiana , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/isolamento & purificação , Ecossistema , Genes de RNAr/genética , Bactérias Aeróbias Gram-Negativas/isolamento & purificação , Hibridização In Situ , Dados de Sequência Molecular , Nitratos/metabolismo , Oxirredução , Oxigênio/análise , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Coloração e Rotulagem , Enxofre/metabolismo , Água/química , Microbiologia da Água
20.
Environ Microbiol ; 4(3): 158-68, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12000316

RESUMO

The occurrence, distribution and activity of archaeal populations within two aerated, activated sludge wastewater treatment systems, one treating domestic waste and the second treating mixed domestic and industrial wastewater, were investigated by denaturing gradient gel electrophoresis (DGGE) analysis of polymerase chain reaction (PCR)-amplified ribosomal RNA gene fragments and process measurements. In the plant receiving mixed industrial and domestic waste the archaeal populations found in the mixed liquor were very similar to those in the influent sewage, though a small number of DGGE bands specific to the mixed liquor were identified. In contrast, the activated sludge treating principally domestic waste harboured distinct archaeal populations associated with the mixed liquor that were not prevalent in the influent sewage. We deduce that the Archaea in the plant treating mixed wastewater were derived principally from the influent, whereas those in the plant treating solely domestic waste were actively growing in the treatment plant. Archaeal 16S rRNA gene sequences related to the Methanosarcinales, Methanomicrobiales and the Methanobacteriales were detected. Methanogenesis was measured in activated sludge samples incubated under oxic and anoxic conditions, demonstrating that the methanogens present in both activated sludge plants were active only in anoxic incubations. The relatively low rates of methanogenesis measured indicated that, although active, the methanogens play a minor role in carbon turnover in activated sludge.


Assuntos
Archaea/crescimento & desenvolvimento , Esgotos/microbiologia , Purificação da Água , Archaea/genética , Archaea/metabolismo , Sequência de Bases , DNA Arqueal/química , DNA Arqueal/genética , Metano/metabolismo , Dados de Sequência Molecular , Filogenia , Reação em Cadeia da Polimerase , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , Reino Unido
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