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BACKGROUND: Although germline BRCA mutations have been associated with adverse outcomes in prostate cancer (PC), understanding of the association between somatic/germline alterations in homologous recombination repair (HRR) genes and treatment outcomes in metastatic castration-resistant PC (mCRPC) is limited. The aim of this study was to investigate the prevalence and outcomes associated with somatic/germline HRR alterations, particularly BRCA1/2, in patients initiating first-line (1L) mCRPC treatment with androgen receptor signalling inhibitors (ARSi) or taxanes. PATIENTS AND METHODS: Data from 729 mCRPC patients were pooled for CAPTURE from four multicentre observational studies. Eligibility required 1L treatment with ARSi or taxanes, adequate tumour samples and biomarker panel results. Patients underwent paired normal and tumour DNA analyses by next-generation sequencing using a custom gene panel including ATM, BRCA1, BRCA2, BRIP1, CDK12, CHEK2, FANCA, HDAC2, PALB2, RAD51B and RAD54L. Patients were divided into subgroups based on somatic/germline alteration(s): with BRCA1/2 mutations (BRCA); with HRR mutations except BRCA1/2 (HRR non-BRCA); and without HRR alterations (non-HRR). Patients without BRCA1/2 mutations were classified as non-BRCA. Radiographic progression-free survival (rPFS), progression-free survival 2 (PFS2) and overall survival (OS) were assessed. RESULTS: Of 729 patients, 96 (13.2%), 127 (17.4%) and 506 (69.4%) were in the BRCA, HRR non-BRCA and non-HRR subgroups, respectively. BRCA patients performed significantly worse for all outcomes than non-HRR or non-BRCA patients (P < 0.05), while PFS2 and OS were significantly shorter for BRCA than HRR non-BRCA patients (P < 0.05). HRR non-BRCA patients also had significantly worse rPFS, PFS2 and OS than non-HRR patients. Exploratory analyses suggested that for BRCA patients, there were no significant differences in outcomes associated with 1L treatment choice (ARSi or taxanes) or with the somatic/germline origin of the alterations. CONCLUSIONS: Worse outcomes were observed for mCRPC patients in the BRCA subgroup compared with non-BRCA subgroups, either HRR non-BRCA or non-HRR. Despite its heterogeneity, the HRR non-BRCA subgroup presented worse outcomes than the non-HRR subgroup. Screening early for HRR mutations, especially BRCA1/2, is crucial in improving mCRPC patient prognosis.
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Mutação em Linhagem Germinativa , Neoplasias de Próstata Resistentes à Castração , Reparo de DNA por Recombinação , Humanos , Masculino , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Neoplasias de Próstata Resistentes à Castração/patologia , Neoplasias de Próstata Resistentes à Castração/mortalidade , Idoso , Reparo de DNA por Recombinação/genética , Pessoa de Meia-Idade , Proteína BRCA2/genética , Idoso de 80 Anos ou mais , Taxoides/uso terapêutico , Proteína BRCA1/genética , Antagonistas de Receptores de Andrógenos/uso terapêutico , Biomarcadores Tumorais/genética , Intervalo Livre de Progressão , MutaçãoRESUMO
BACKGROUND: Tuberculosis (TB) is the major killer of people living with human immunodeficiency virus (HIV) globally, with suboptimal diagnostics and management contributing to high case-fatality rates. METHODS: A prospective cohort of patients with confirmed TB (Xpert MTB/RIF and/or Determine TB-LAM Ag positive) identified through screening HIV-positive inpatients with sputum and urine diagnostics in Malawi and South Africa (Rapid urine-based Screening for Tuberculosis to reduce AIDS Related Mortality in hospitalized Patients in Africa [STAMP] trial). Urine was tested prospectively (intervention) or retrospectively (standard of care arm). We defined baseline clinical phenotypes using hierarchical cluster analysis, and also used Cox regression analysis to identify associations with early mortality (≤56 days). RESULTS: Of 322 patients with TB confirmed between October 2015 and September 2018, 78.0% had ≥1 positive urine test. Antiretroviral therapy (ART) coverage was 80.2% among those not newly diagnosed, but with median CD4 count 75 cells/µL and high HIV viral loads. Early mortality was 30.7% (99/322), despite near-universal prompt TB treatment. Older age, male sex, ART before admission, poor nutritional status, lower hemoglobin, and positive urine tests (TB-LAM and/or Xpert MTB/RIF) were associated with increased mortality in multivariate analyses. Cluster analysis (on baseline variables) defined 4 patient subgroups with early mortality ranging from 9.8% to 52.5%. Although unadjusted mortality was 9.3% lower in South Africa than Malawi, in adjusted models mortality was similar in both countries (hazard ratio, 0.9; P = .729). CONCLUSIONS: Mortality following prompt inpatient diagnosis of HIV-associated TB remained unacceptably high, even in South Africa. Intensified management strategies are urgently needed, for which prognostic indicators could potentially guide both development and subsequent use.
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Síndrome da Imunodeficiência Adquirida , Infecções por HIV , Mycobacterium tuberculosis , Tuberculose , Idoso , HIV , Infecções por HIV/complicações , Humanos , Malaui/epidemiologia , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Sensibilidade e Especificidade , África do Sul/epidemiologia , Escarro , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológicoRESUMO
The original version of this article unfortunately contained some mistakes.
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BACKGROUND: Testing urine improves the number of tuberculosis diagnoses made among patients in hospital with HIV. In conjunction with the two-country randomised Rapid Urine-based Screening for Tuberculosis to Reduce AIDS-related Mortality in Hospitalised Patients in Africa (STAMP) trial, we used a microsimulation model to estimate the effects on clinical outcomes and the cost-effectiveness of adding urine-based tuberculosis screening to sputum screening for hospitalised patients with HIV. METHODS: We compared two tuberculosis screening strategies used irrespective of symptoms among hospitalised patients with HIV in Malawi and South Africa: a GeneXpert assay (Cepheid, Sunnyvale, CA, USA) for Mycobacterium tuberculosis and rifampicin resistance (Xpert) in sputum samples (standard of care) versus sputum Xpert combined with a lateral flow assay for M tuberculosis lipoarabinomannan in urine (Determine TB-LAM Ag test, Abbott, Waltham, MA, USA [formerly Alere]; TB-LAM) and concentrated urine Xpert (intervention). A cohort of simulated patients was modelled using selected characteristics of participants, tuberculosis diagnostic yields, and use of hospital resources in the STAMP trial. We calibrated 2-month model outputs to the STAMP trial results and projected clinical and economic outcomes at 2 years, 5 years, and over a lifetime. We judged the intervention to be cost-effective if the incremental cost-effectiveness ratio (ICER) was less than US$750/year of life saved (YLS) in Malawi and $940/YLS in South Africa. A modified intervention of adding only TB-LAM to the standard of care was also evaluated. We did a budget impact analysis of countrywide implementation of the intervention. FINDINGS: The intervention increased life expectancy by 0·5-1·2 years and was cost-effective, with an ICER of $450/YLS in Malawi and $840/YLS in South Africa. The ICERs decreased over time. At lifetime horizon, the intervention remained cost-effective under nearly all modelled assumptions. The modified intervention was at least as cost-effective as the intervention (ICERs $420/YLS in Malawi and $810/YLS in South Africa). Over 5 years, the intervention would save around 51â000 years of life in Malawi and around 171â000 years of life in South Africa. Health-care expenditure for screened individuals was estimated to increase by $37 million (10·8%) and $261 million (2·8%), respectively. INTERPRETATION: Urine-based tuberculosis screening of all hospitalised patients with HIV could increase life expectancy and be cost-effective in resource-limited settings. Urine TB-LAM is especially attractive because of high incremental diagnostic yield and low additional cost compared with sputum Xpert, making a compelling case for expanding its use to all hospitalised patients with HIV in areas with high HIV burden and endemic tuberculosis. FUNDING: UK Medical Research Council, UK Department for International Development, Wellcome Trust, US National Institutes of Health, Royal College of Physicians, Massachusetts General Hospital.
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Infecções por HIV/epidemiologia , Lipopolissacarídeos/urina , Tuberculose Pulmonar/diagnóstico , Adulto , Fármacos Anti-HIV/uso terapêutico , Simulação por Computador , Análise Custo-Benefício , Feminino , Infecções por HIV/tratamento farmacológico , Hospitalização , Humanos , Malaui , Masculino , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Mortalidade , Técnicas de Amplificação de Ácido Nucleico , África do Sul , Escarro/microbiologia , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Tuberculose/urina , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/urinaRESUMO
Many mammals enhance their olfactory signals visually by depositing them in conspicuous locations such as well-travelled paths. It is also possible to enhance the odour itself through behaviours aimed at modifying odour emission rates. White rhinos defecate in communal middens. While defecating, territorial males kick sharply with their back feet which disperses their dung. Despite being a ubiquitous trait of territorial male white rhinos, the reason behind this behaviour is unclear. We hypothesised that the purpose of dung kicking was for olfactory signal amplification (OSA) in terms of an increased emission of volatile compounds (i.e. increased signal strength). Using dung collected from non-territorial adult males (because it is not possible to collect whole dung from territorial males), we show that the dispersal of male white rhino dung causes OSA by increasing the emission of hydrocarbon acids. The dung odour of territorial and non-territorial males differs only quantitatively, hence it is likely that the same emission patterns occur for territorial male dung odours following dung dispersal. The volatile compound indicating age of intact dung was toluene, but for dispersed dung it was acetophenone (similar to territorial male dung). Despite the benefits of OSA, dung dispersal carried a cost of decreased odour longevity. Thus, signal detectability is temporally reduced. However, territorial males likely counteract this by defecating in middens both before and during peak visitation times by other individuals (15:00-23:00). As a result, we suggest that dung kicking by territorial males amplifies signal strength, such that their dung odours are the most prominent and easily detectable by individuals visiting the middens. This would then better signal territorial ownership to both potential rivals and potential mates.
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Fezes/química , Perissodáctilos/fisiologia , Olfato , Animais , Comportamento Animal , Cromatografia Gasosa-Espectrometria de Massas , Masculino , Territorialidade , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/químicaRESUMO
BACKGROUND: Current diagnostics for HIV-associated tuberculosis are suboptimal, with missed diagnoses contributing to high hospital mortality and approximately 374â000 annual HIV-positive deaths globally. Urine-based assays have a good diagnostic yield; therefore, we aimed to assess whether urine-based screening in HIV-positive inpatients for tuberculosis improved outcomes. METHODS: We did a pragmatic, multicentre, double-blind, randomised controlled trial in two hospitals in Malawi and South Africa. We included HIV-positive medical inpatients aged 18 years or more who were not taking tuberculosis treatment. We randomly assigned patients (1:1), using a computer-generated list of random block size stratified by site, to either the standard-of-care or the intervention screening group, irrespective of symptoms or clinical presentation. Attending clinicians made decisions about care; and patients, clinicians, and the study team were masked to the group allocation. In both groups, sputum was tested using the Xpert MTB/RIF assay (Xpert; Cepheid, Sunnyvale, CA, USA). In the standard-of-care group, urine samples were not tested for tuberculosis. In the intervention group, urine was tested with the Alere Determine TB-LAM Ag (TB-LAM; Alere, Waltham, MA, USA), and Xpert assays. The primary outcome was all-cause 56-day mortality. Subgroup analyses for the primary outcome were prespecified based on baseline CD4 count, haemoglobin, clinical suspicion for tuberculosis; and by study site and calendar time. We used an intention-to-treat principle for our analyses. This trial is registered with the ISRCTN registry, number ISRCTN71603869. FINDINGS: Between Oct 26, 2015, and Sept 19, 2017, we screened 4788 HIV-positive adults, of which 2600 (54%) were randomly assigned to the study groups (n=1300 for each group). 13 patients were excluded after randomisation from analysis in each group, leaving 2574 in the final intention-to-treat analysis (n=1287 in each group). At admission, 1861 patients were taking antiretroviral therapy and median CD4 count was 227 cells per µL (IQR 79-436). Mortality at 56 days was reported for 272 (21%) of 1287 patients in the standard-of-care group and 235 (18%) of 1287 in the intervention group (adjusted risk reduction [aRD] -2·8%, 95% CI -5·8 to 0·3; p=0·074). In three of the 12 prespecified, but underpowered subgroups, mortality was lower in the intervention group than in the standard-of-care group for CD4 counts less than 100 cells per µL (aRD -7·1%, 95% CI -13·7 to -0·4; p=0.036), severe anaemia (-9·0%, -16·6 to -1·3; p=0·021), and patients with clinically suspected tuberculosis (-5·7%, -10·9 to -0·5; p=0·033); with no difference by site or calendar period. Adverse events were similar in both groups. INTERPRETATION: Urine-based tuberculosis screening did not reduce overall mortality in all HIV-positive inpatients, but might benefit some high-risk subgroups. Implementation could contribute towards global targets to reduce tuberculosis mortality. FUNDING: Joint Global Health Trials Scheme of the Medical Research Council, the UK Department for International Development, and the Wellcome Trust.
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Infecções Oportunistas Relacionadas com a AIDS/urina , Países em Desenvolvimento , Soropositividade para HIV/urina , Programas de Rastreamento , Tuberculose/urina , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/tratamento farmacológico , Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Adulto , Método Duplo-Cego , Farmacorresistência Bacteriana , Feminino , Soropositividade para HIV/tratamento farmacológico , Soropositividade para HIV/mortalidade , Humanos , Malaui , Masculino , Pessoa de Meia-Idade , Rifampina/uso terapêutico , África do Sul , Escarro/microbiologia , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/mortalidade , UrináliseRESUMO
Healthcare workers (HCWs) play a central role in global tuberculosis (TB) elimination efforts but their contributions are undermined by occupational TB. HCWs have higher rates of latent and active TB than the general population due to persistent occupational TB exposure, particularly in settings where there is a high prevalence of undiagnosed TB in healthcare facilities and TB infection control (TB-IC) programmes are absent or poorly implemented. Occupational health programmes in high TB burden settings are often weak or non-existent and thus data that record the extent of the increased risk of occupational TB globally are scarce. HCWs represent a limited resource in high TB burden settings and occupational TB can lead to workforce attrition. Stigma plays a role in delayed diagnosis, poor treatment outcomes and impaired well-being in HCWs who develop TB. Ensuring the prioritization and implementation of TB-IC interventions and occupational health programmes, which include robust monitoring and evaluation, is critical to reduce nosocomial TB transmission to patients and HCWs. The provision of preventive therapy for HCWs with latent TB infection (LTBI) can also prevent progression to active TB. Unlike other patient groups, HCWs are in a unique position to serve as agents of change to raise awareness, advocate for necessary resource allocation and implement TB-IC interventions, with appropriate support from dedicated TB-IC officers at the facility and national TB programme level. Students and community health workers (CHWs) must be engaged and involved in these efforts. Nosocomial TB transmission is an urgent public health problem and adopting rights-based approaches can be helpful. However, these efforts cannot succeed without increased political will, supportive legal frameworks and financial investments to support HCWs in efforts to decrease TB transmission.
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Defesa do Consumidor , Infecção Hospitalar/prevenção & controle , Pessoal de Saúde , Doenças Profissionais/prevenção & controle , Tuberculose/prevenção & controle , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/transmissão , Feminino , Pessoal de Saúde/educação , Direitos Humanos , Humanos , Controle de Infecções/legislação & jurisprudência , Controle de Infecções/organização & administração , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Transmissão de Doença Infecciosa do Profissional para o Paciente/prevenção & controle , Pessoal de Laboratório , Tuberculose Latente/epidemiologia , Masculino , Doenças Profissionais/epidemiologia , Exposição Ocupacional , Serviços de Saúde do Trabalhador/organização & administração , Retorno ao Trabalho , Fatores de Risco , Estudantes de Medicina , Tuberculose/epidemiologia , Tuberculose/transmissãoRESUMO
BACKGROUND: HIV-associated tuberculosis (TB) co-infection remains an enormous burden to international public health. Post-mortem studies have highlighted the high proportion of HIV-positive adults admitted to hospital with TB. Determine TB-LAM and Xpert MTB/RIF assays can substantially increase diagnostic yield of TB within one day of hospital admission. However, it remains unclear if this approach can impact clinical outcomes. The STAMP trial aims to test the hypothesis that the implementation a urine-based screening strategy for TB can reduce all cause-mortality among HIV-positive patients admitted to hospital when compared to current, sputum-based screening. METHODS: The trial is a pragmatic, individually randomised, multi-country (Malawi and South Africa) clinical trial with two study arms (1:1 recruitment). Unselected HIV-positive patients admitted to medical wards, irrespective of presentation, meeting the inclusion criteria and giving consent will be randomized to screening for TB using either: (i) 'standard of care'- testing of sputum using the Xpert MTB/RIF assay (Xpert) or (ii) 'intervention'- testing of sputum using Xpert and testing of urine using (a) Determine TB-LAM lateral-flow assay and (b) Xpert following concentration of urine by centrifugation. Patients will be excluded if they have received TB treatment in the previous 12 months, if they have received isoniazid preventive therapy in the last 6 months, if they are aged <18 years or they live outside the pre-specified geographical area. Results will be provided to the responsible medical team as soon as available to inform decisions regarding TB treatment. Both the study and routine medical team will be masked to study arm allocation. 1300 patients will be enrolled per arm (equal numbers at the two trial sites). The primary endpoint is all-cause mortality at 56 days. An economic analysis will be conducted to project long-term outcomes for shorter-term trial data, including cost-effectiveness. DISCUSSION: This pragmatic trial assesses an intervention to reduce the high mortality caused by HIV-associated TB, which could feasibly be scaled up in high-burden settings if shown to be efficacious and cost-effective. We discuss the challenges of designing a trial to assess the impact on mortality of laboratory-based TB screening interventions given frequent initiation of empirical treatment and a failure of several previous clinical trials to demonstrate an impact on clinical outcomes. We also elaborate on the practical and ethical issues of 'testing a test' in general. TRIAL REGISTRATION: ISRCTN Registry ( ISRCTN71603869 ) prospectively registered 08 May 2015; the South African National Controlled Trials Registry (DOH-27-1015-5185) prospectively registered October 2015.
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Infecções Oportunistas Relacionadas com a AIDS/urina , Síndrome da Imunodeficiência Adquirida/complicações , Infecções por HIV/complicações , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Tuberculose/urina , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Síndrome da Imunodeficiência Adquirida/microbiologia , Síndrome da Imunodeficiência Adquirida/mortalidade , Adulto , Infecções por HIV/microbiologia , Hospitalização , Humanos , Isoniazida/uso terapêutico , Malaui , Programas de Rastreamento , África do Sul , Escarro/microbiologia , Tuberculose/diagnóstico , Tuberculose/prevenção & controle , Urinálise/métodosRESUMO
BACKGROUND: Simple immune capture assays that detect mycobacterial lipoarabinomannan (LAM) antigen in urine are promising new tools for the diagnosis of HIV-associated tuberculosis (HIV-TB). In addition, however, recent prospective cohort studies of patients with HIV-TB have demonstrated associations between LAM in the urine and increased mortality risk during TB treatment, indicating an additional utility of urinary LAM as a prognostic marker. We conducted a systematic review and meta-analysis to summarise the evidence concerning the strength of this relationship in adults with HIV-TB in sub-Saharan Africa, thereby quantifying the assay's prognostic value. METHODS: We searched MEDLINE and Embase databases using comprehensive search terms for 'HIV', 'TB', 'LAM' and 'sub-Saharan Africa'. Identified studies were reviewed and selected according to predefined criteria. RESULTS: We identified 10 studies eligible for inclusion in this systematic review, reporting on a total of 1172 HIV-TB cases. Of these, 512 patients (44 %) tested positive for urinary LAM. After a variable duration of follow-up of between 2 and 6 months, overall case fatality rates among HIV-TB cases varied between 7 % and 53 %. Pooled summary estimates generated by random-effects meta-analysis showed a two-fold increased risk of mortality for urinary LAM-positive HIV-TB cases compared to urinary LAM-negative HIV-TB cases (relative risk 2.3, 95 % confidence interval 1.6-3.1). Some heterogeneity was explained by study setting and patient population in sub-group analyses. Five studies also reported multivariable analyses of risk factors for mortality, and pooled summary estimates demonstrated over two-fold increased mortality risk (odds ratio 2.5, 95 % confidence interval 1.4-4.5) among urinary LAM-positive HIV-TB cases, even after adjustment for other risk factors for mortality, including CD4 cell count. CONCLUSIONS: We have demonstrated that detectable LAM in urine is associated with increased risk of mortality during TB treatment, and that this relationship remains after adjusting for other risk factors for mortality. This may simply be due to a positive test for urinary LAM serving as a marker of higher mycobacterial load and greater disease dissemination and severity. Alternatively, LAM antigen may directly compromise host immune responses through its known immunomodulatory effects. Detectable LAM in the urine is an independent risk factor for mortality among patients receiving treatment for HIV-TB. Further research is warranted to elucidate the underlying mechanisms and to determine whether this vulnerable patient population may benefit from adjunctive interventions.
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Biomarcadores/urina , Infecções por HIV/complicações , Lipopolissacarídeos/urina , Tuberculose/mortalidade , Tuberculose/urina , Adulto , África Subsaariana , Feminino , Humanos , Masculino , Prognóstico , Estudos Prospectivos , Fatores de Risco , Tuberculose/complicaçõesRESUMO
Dr Thato Mosidi never expected to be diagnosed with tuberculosis (TB), despite widely prevalent exposure and very limited infection control measures. The life-threatening diagnosis of primary extensively drug-resistant TB (XDR-TB) came as an even greater shock. The inconvenient truth is that, rather than being protected, Dr Mosidi and thousands of her healthcare colleagues are at an increased risk of TB and especially drug-resistant TB. In this viewpoint paper we debunk the widely held false belief that healthcare workers are somehow immune to TB disease (TB-proof) and explore some of the key factors contributing to the pervasive stigmatization and subsequent non-disclosure of occupational TB. Our front-line workers are some of the first to suffer the consequences of a progressively more resistant and fatal TB epidemic, and urgent interventions are needed to ensure the safety and continued availability of these precious healthcare resources. These include the rapid development and scale-up of improved diagnostic and treatment options, strengthened infection control measures, and focused interventions to tackle stigma and discrimination in all its forms. We call our colleagues to action to protect themselves and those they care for.
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Pessoal de Saúde , Transmissão de Doença Infecciosa do Paciente para o Profissional , Tuberculose Resistente a Múltiplos Medicamentos/transmissão , Tuberculose Extensivamente Resistente a Medicamentos/transmissão , Feminino , Humanos , Controle de Infecções , Prevalência , Risco , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/prevenção & controleRESUMO
Plants are expected to emit floral scent when their pollinators are most active. In the case of long-tubed flowers specialised for pollination by crepuscular or nocturnal moths, scent emissions would be expected to peak during dawn. Although this classic idea has existed for decades, it has rarely been tested quantitatively. We investigated the timing of flower visitation, pollination and floral scent emissions in six long-spurred Satyrium species (Orchidaceae). We observed multiple evening visits by pollinaria-bearing moths on flowers of all study species, but rarely any diurnal visits. The assemblages of moth pollinators differed among Satyrium species, even those that co-flowered, and the lengths of moth tongues and floral nectar spurs were strongly correlated, suggesting that the available moth pollinator fauna is partitioned by floral traits. Pollinarium removal occurred more frequently during the night than during the day in four of the six species. Scent emission, however, was only significantly higher at dusk than midday in two species. Analysis of floral volatiles using gas chromatography coupled with mass spectrometry yielded 168 scent compounds, of which 112 were species-specific. The scent blends emitted by each species occupy discrete clusters in two-dimensional phenotype space, based on multivariate analysis. We conclude that these long-spurred Satyrium species are ecologically specialised for moth pollination, yet the timing of their scent emission is not closely correlated with moth pollination activity. Scent composition was also more variable than expected from a group of closely related plants sharing the same pollinator functional group. These findings reveal a need for greater understanding of mechanisms of scent production and their constraints, as well as the underlying reasons for divergent scent chemistry among closely related plants.
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Mariposas/fisiologia , Óleos Voláteis/metabolismo , Orchidaceae/fisiologia , Polinização/fisiologia , Animais , Flores/química , Flores/fisiologia , Fenótipo , Néctar de Plantas/fisiologia , Especificidade da Espécie , Fatores de TempoRESUMO
BACKGROUND: Although the evidence base regarding the use of the Xpert MTB/RIF assay for diagnosis of pulmonary tuberculosis (TB) when testing respiratory samples is well established, the evidence base for its diagnostic accuracy for extrapulmonary and sputum-scarce pulmonary TB when testing non-respiratory samples is less clearly defined. METHODS: A systematic literature search of 7 electronic databases (Medline, EMBASE, ISI Web of Science, BIOSIS, Global Health Database, Scopus and Cochrane Database) was conducted to identify studies of the diagnostic accuracy of the Xpert assay when testing non-respiratory samples compared with a culture-based reference standard. Data were extracted and study quality was assessed using the QUADAS-2 tool. Sensitivities and specificities were calculated on a per-sample basis, stratified by sample type and smear microscopy status and summarised using forest plots. Pooled estimates were calculated for groups with sufficient data. RESULTS: Twenty-seven studies with a total of 6,026 non-respiratory samples were included. Among the 23 studies comparing Xpert and culture done on the same samples, sensitivity was very heterogeneous with a median sensitivity of 0.83 (IQR, 0.68-0.94) whereas specificities were typically very high (median, 0.98; IQR, 0.89-1.00). The pooled summary estimates of sensitivity when testing smear-positive and smear-negative samples were 0.95 (95% CI 0.91-1.00) and 0.69 (95% CI 0.60-0.80), respectively. Pooled summary estimates of sensitivity varied substantially between sample types: lymph node tissue, 0.96 (95% CI, 0.72-0.99); tissue samples of all types, 0.88 (95% CI, 0.76-0.94); pleural fluid, 0.34 (95% CI, 0.24-0.44); gastric aspirates for diagnosis of sputum-scarce pulmonary TB, 0.78 (IQR, 0.68 - 0.85). Median sensitivities when testing cerebrospinal fluid and non-pleural serous fluid samples were 0.85 (IQR, 0.75-1.00) and 0.67 (IQR, 0.00-1.00), respectively. CONCLUSION: Xpert detects with high specificity the vast majority of EPTB cases with smear-positive non-respiratory samples and approximately two-thirds of those with smear-negative samples. Xpert is a useful rule-in diagnostic test for EPTB, especially when testing cerebrospinal fluid and tissue samples. In addition, it has a high sensitivity for detecting pulmonary TB when using gastric aspirate samples. These findings support recent WHO guidelines regarding the use of Xpert for TB diagnosis from non-respiratory samples.
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Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/diagnóstico , Antibióticos Antituberculose/farmacologia , Farmacorresistência Bacteriana , Exsudatos e Transudatos/microbiologia , Fezes/microbiologia , Humanos , Rifampina/farmacologia , Sensibilidade e Especificidade , Tuberculose Pulmonar/microbiologiaRESUMO
Floral nectar composition has been explained as an adaptation to factors that are either directly or indirectly related to pollinator attraction. However, it is often unclear whether the sugar composition is a direct adaptation to pollinator preferences. Firstly, the lower osmolality of sucrose solutions means that they evaporate more rapidly than hexose solutions, which might be one reason why sucrose-rich nectar is typically found in flowers with long tubes (adapted to long-tongued pollinators), where it is better protected from evaporation than in open or short-tubed flowers. Secondly, it can be assumed that temperature-dependent evaporation is generally lower during the night than during the day so that selection pressure to secrete nectar with high osmolality (i.e. hexose-rich solutions) is relaxed for night-active flowers pollinated at night. Thirdly, the breeding system may affect selection pressure on nectar traits; that is, for pollinator-independent, self-pollinated plants, a lower selective pressure on nectar traits can be assumed, leading to a higher variability of nectar sugar composition independent of pollinator preferences, nectar accessibility and nectar protection. To analyse the relations between flower tube length, day vs. night pollination and self-pollination, the nectar sugar composition was investigated in 78 European Caryophylloideae (Caryophyllaceae) with different pollination modes (diurnal, nocturnal, self-pollination) using high-performance liquid chromatography (HPLC). All Caryophylleae species (Dianthus and relatives) were found to have nectar with more than 50% sucrose, whereas the sugar composition of Sileneae species (Silene and relatives) ranged from 0% to 98.2%. In the genus Silene, a clear dichotomous distribution of sucrose- and hexose-dominant nectars is evident. We found a positive correlation between the flower tube length and sucrose content in Caryophylloideae, particularly in day-flowering species, using both conventional analyses and phylogenetically independent contrasts.
Assuntos
Caryophyllaceae/metabolismo , Néctar de Plantas/química , Polinização , Caryophyllaceae/anatomia & histologia , Caryophyllaceae/classificação , Cromatografia Líquida de Alta Pressão , Ritmo Circadiano , Flores/anatomia & histologia , Flores/metabolismo , Frutose/química , Frutose/metabolismo , Glucose/química , Glucose/metabolismo , Filogenia , Néctar de Plantas/metabolismo , Sacarose/química , Sacarose/metabolismoRESUMO
In 2008 and 2009, severe fire blight (Erwinia amylovora) occurred in Illinois apple orchards, leading to speculation that streptomycin-resistant strains of E. amylovora might be present in some orchards. Statewide surveys were conducted in 2010, 2011, and 2012, and 117, 129, and 170, E. amylovora isolates were collected, respectively, from 20 counties. None of the 416 E. amylovora isolates tested were resistant to streptomycin (Agri-Mycin 17WP) at 50 mg/liter. Seven non-E. amylovora bacterial isolates were collected from E. amylovora-infected shoots that contained both a strA-strB streptomycin resistance gene and IS1133 on transposon Tn5393, which could be a potential source of streptomycin resistance for E. amylovora in Illinois in the future. Colony development of all 84 E. amylovora isolates tested was inhibited on Luria-Bertani medium amended with oxytetracycline at 50 mg/liter and kasugamycin (Kasumin 2L) at 100 mg/liter. Similarly, colony development of the 84 E. amylovora isolates was inhibited on casitone-yeast extract medium amended with copper sulfate at 0.16 mM. In 2011 and 2012, field trials were conducted to evaluate the efficacy of oxytetracycline (Mycoshield 17WP), kasugamycin (Kasumin 2L and ARY-4016-06), copper hydroxide (Kocide-3000 41.6DF), Bacillus subtilis (Serenade Max, QST713), and Pseudomonas fluorescens (Blight Ban A506) for management of fire blight in an apple orchard. Only kasugamycin (Kasumin 2L and ARY-4016-06) reduced blossom infection significantly. There was a significant interaction of kasugamycin (Kasumin 2L) with prohexadione calcium (Apogee 27.5DF) in reducing shoot blight incidence in the field in 2012.
RESUMO
Because of increased interest in the use of local provenances for restoration or landscaping projects, information about the genetic differentiation of plant species is required to delineate provenances for seed collection. To obtain information about population distinctiveness of endangered Rosa species occurring in Brandenburg (northeast Germany), we investigated the genetic differentiation of Rosa inodora, R. sherardii and R. subcollina using RAPD markers. All three species were uncommon in our study region. Φ-statistics, estimated by amova, revealed a low interpopulation differentiation for R. inodora (Φ(PT) = 0.19, P < 0.0001) and higher values for R. sherardii and R. subcollina (Φ(PT) = 0.29 and 0.30, P < 0.0001). UPGMA dendrograms and NMDS showed clear spatial differentiation for all species and a correlation between geographic and genetic distances. Due to predominantly high values of genetic differentiation and spatial patterns of ordination, we suggest small provenance regions for endangered Rosa species for seed collection.
Assuntos
Rosa/genética , DNA de Plantas/genética , Demografia , Espécies em Perigo de Extinção , Marcadores Genéticos , Variação Genética , Alemanha , Técnica de Amplificação ao Acaso de DNA Polimórfico , Rosa/classificaçãoRESUMO
In the Silene latifolia-Hadena bicruris nursery pollination system, the Hadena moth is both pollinator and seed predator of its host plant. Floral scent, which differs among S. latifolia individuals and populations, is important for adult Hadena to locate its host. However, the success of moth larvae is strongly reduced if hosts are infected by the anther smut fungus Microbotryum violaceum, a pathogen that is transmitted by flower visitors. There were no qualitative differences between the scent of flowers from healthy and diseased plants. In addition, electroantennographic measurements showed that Hadena responded to the same subset of 19 compounds in samples collected from healthy and diseased plants. However, there were significant quantitative differences in scent profiles. Flowers from diseased plants emitted both a lower absolute amount of floral scent and had a different scent pattern, mainly due to their lower absolute amount of lilac aldehyde, whereas their amount of (E)-beta-ocimene was similar to that in healthy flowers. Dual choice behavioral wind tunnel tests using differently scented flowers confirmed that moths respond to both qualitative and quantitative aspects of floral scent, suggesting that they could use differences in floral scent between healthy and infected plants to discriminate against diseased plants. Population mean fruit predation rates significantly increased with population mean levels of the emission rates of lilac aldehyde per flower, indicating that selection on floral scent compounds may not only be driven by effects on pollinator attraction but also by effects on fruit predation. However, variation in mean emission rates of scent compounds per flower generally could not explain the higher fruit predation in populations originating from the introduced North American range compared to populations native to Europe.
Assuntos
Basidiomycota/fisiologia , Mariposas/fisiologia , Odorantes , Oviposição , Doenças das Plantas/microbiologia , Silene/fisiologia , Monoterpenos Acíclicos , Aldeídos/química , Aldeídos/metabolismo , Alcenos/química , Alcenos/metabolismo , Animais , Comportamento Animal , Flores/química , Flores/fisiologia , Frutas , Cromatografia Gasosa-Espectrometria de Massas , Interações Hospedeiro-Parasita , Odorantes/análise , Pólen/fisiologiaRESUMO
BACKGROUND: Electroconvulsive therapy, a standard treatment in mood disorders, is sometimes also indicated in psychotic disorders, especially in the treatment of refractory schizophrenia. In this instance, maintenance electroconvulsive therapy (M-ECT) can also become a long-term treatment. This paper presents the effects of M-ECT in the treatment of refractory schizophrenia using a retrospective analysis. Previous works showed that electroconvulsive therapy is effective on catatonia, anxiety with somatisation, lack of compliance, opposition, delusions especially with hallucinations and persecution, anorexia, agitation, carelessness, aggressive behaviour and moral pain. It is ineffective on bewilderment, somatic complaints and negative symptoms. AIM OF THE STUDY: A retrospective analysis of a clinical cohort of patients treated with M-ECT was carried out to determine the specific indications of M-ECT, its effectiveness on clinical symptoms, quality of life, relapse rates and use of medication. Nineteen patients with DSM-IV diagnosis of paranoid schizophrenia (n=5), schizophrenia with neurotic symptoms (n=3), disorganized schizophrenia (n=1), hebephrenia (n=3) and schizoaffective disorder (n=8), treated in the department of the University Hospital of Sainte-Anne in Paris, received M-ECT between 1991 and 2005. Seven patients are still under this treatment. Their mean age at the beginning of treatment was 47.5 years with a mean duration of the illness of 24 years. The indication of M-ECT was the increase of acute episodes, an increase of symptoms intensity, the inefficiency or intolerance to pharmacological treatments or an early relapse after ECT discontinuation. All patients had previously been successfully treated by ECT during an acute episode. Each patient received an average of 47 bilateral M-ECT under general anaesthesia at one to five weeks' intervals for a mean period of 43 months. All of them were also treated by antipsychotics; in addition, 30% received mood stabilizers and 10% antidepressants. The dosage of antidepressants and mood stabilizers was reduced during M-ECT treatment, especially in patients with schizoaffective disorder, probably in relation with the effectiveness of ECT on mood symptoms. RESULTS: During M-ECT, the mean duration of yearly hospitalizations was decreased by 80% and the mean duration of each hospitalization by 40% with a better ability to take part in activities, sometimes even to return home or go back to work. There was also a positive effect on quality of life considering the severity of symptoms and the long psychiatric history of these patients. The possibility to go from a full time hospitalization to a day-care facility or to live in a halfway house can be considered as a huge progress. M-ECT was efficient on mood symptoms, delusions, anorexia, suicidal impetus, anxiety symptoms and increased cooperation and treatment compliance. Efficacy on obsessive compulsive symptoms was less obvious. There was no effect on dissociation and negative symptoms. Relapses essentially occurred after a stressful life event, a too long interval between the M-ECT sessions or, in 50% of the cases, without any obvious etiology. It required a revision of the M-ECT program and, most of the time, an hospitalization for full ECT treatment. DISCUSSION: There is no consensus on the rate and number of M-ECT as it varies from patient to patient and depends upon the extent of the clinical response and side effects. The discontinuation of M-ECT will depend on the clinical symptoms, compliance and tolerance to ECT. As it is the case with ECT treatment for an acute episode, available evidence suggests that treatment with antipsychotics should continue during the maintenance ECT course. CONCLUSION: Maintenance electroconvulsive therapy combined with medication may be an efficient alternative to pharmacological treatment alone in refractory schizophrenia. Alternative therapeutical strategies are crucial in this domain, due to the important public health problem it raises. There are few randomised prospective controlled clinical trials regarding this treatment and further clinical investigations are necessary, notably to define standardized criteria for M-ECT programs.
Assuntos
Eletroconvulsoterapia , Transtornos Psicóticos/terapia , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Doença Aguda , Adulto , Estudos de Coortes , Feminino , Humanos , Acontecimentos que Mudam a Vida , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/psicologia , Recidiva , Retratamento , Estudos Retrospectivos , Resultado do TratamentoRESUMO
The flowers of Canada thistle, Cirsium arvense (L.), attract a wide range of insects, including pollinators and herbivorous species. This attraction is primarily mediated by floral odor, which offers potential for developing generic insect attractants based on odor. In this study, we have analyzed the chemical composition of the volatiles produced by Canada thistle flowers. Nineteen floral compounds were identified in the headspace, including phenylacetaldehyde (55%), methyl salicylate (14%), dimethyl salicylate (8%), pyranoid linalool oxide (4.5%), and benzaldehyde (3.5%). Other minor compounds include benzyl alcohol, methylbenzoate, linalool, phenylethyl alcohol, furanoid linalool oxide, p-anisaldehyde, 2,6-dimethyl-1,3,5,7-octatetraene, benzylacetate, benzyl tiglate, (E,E)-alpha-farnesene, benzyl benzoate, isopropyl myristate, and 2-phenylethyl ester benzoic acid. The relative attractiveness of various doses of the main floral volatile compound phenylacetaldehyde (i.e., 10, 100, 200, and 400 mg) was tested for insect attraction. Both the total catch and the biodiversity of insect species trapped increased as the loading of phenylacetaldehyde increased. Volatiles were chosen from the odors from the flowers of Canada thistle and formulated and tested in the field. An 11-component blend was the most attractive of several floral blends tested. These findings indicate that chemical components of flower odors of Canada thistle can serve as a generic insect attractant for monitoring of invasive pest species.
Assuntos
Cirsium/parasitologia , Flores/química , Insetos/fisiologia , Odorantes , Feromônios , Animais , Cirsium/química , Insetos/classificação , Insetos/patogenicidade , Óleos Voláteis/análise , Especificidade da EspécieRESUMO
Since the 1970s it has been known that the nursery pollinator Hadena bicruris is attracted to the flowers of its most important host plant, Silene latifolia, by their scent. Here we identified important compounds for attraction of this noctuid moth. Gas chromatographic and electroantennographic methods were used to detect compounds eliciting signals in the antennae of the moth. Electrophysiologically active compounds were tested in wind-tunnel bioassays to foraging naïve moths, and the attractivity of these compounds was compared with that to the natural scent of whole S. latifolia flowers. The antennae of moths detected substances of several classes. Phenylacetaldehyde elicited the strongest signals in the antennae, but lilac aldehydes were the most attractive compounds in wind-tunnel bioassays and attracted 90% of the moths tested, as did the scent of single flowers. Our results show that the most common and abundant floral scent compounds in S. latifolia, lilac aldehydes, attracted most of the moths tested, indicating a specific adaptation of H. bicruris to its host plant.