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1.
PLoS Pathog ; 7(3): e1001320, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21445237

RESUMO

The presence of bacteria in the midgut of mosquitoes antagonizes infectious agents, such as Dengue and Plasmodium, acting as a negative factor in the vectorial competence of the mosquito. Therefore, knowledge of the molecular mechanisms involved in the control of midgut microbiota could help in the development of new tools to reduce transmission. We hypothesized that toxic reactive oxygen species (ROS) generated by epithelial cells control bacterial growth in the midgut of Aedes aegypti, the vector of Yellow fever and Dengue viruses. We show that ROS are continuously present in the midgut of sugar-fed (SF) mosquitoes and a blood-meal immediately decreased ROS through a mechanism involving heme-mediated activation of PKC. This event occurred in parallel with an expansion of gut bacteria. Treatment of sugar-fed mosquitoes with increased concentrations of heme led to a dose dependent decrease in ROS levels and a consequent increase in midgut endogenous bacteria. In addition, gene silencing of dual oxidase (Duox) reduced ROS levels and also increased gut flora. Using a model of bacterial oral infection in the gut, we show that the absence of ROS resulted in decreased mosquito resistance to infection, increased midgut epithelial damage, transcriptional modulation of immune-related genes and mortality. As heme is a pro-oxidant molecule released in large amounts upon hemoglobin degradation, oxidative killing of bacteria in the gut would represent a burden to the insect, thereby creating an extra oxidative challenge to the mosquito. We propose that a controlled decrease in ROS levels in the midgut of Aedes aegypti is an adaptation to compensate for the ingestion of heme.


Assuntos
Aedes/microbiologia , Heme/metabolismo , Hemoglobinas/metabolismo , Proteínas de Insetos/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Animais , Heme/farmacologia , Hemoglobinas/farmacologia , Humanos , Coelhos
2.
Neuroepidemiology ; 41(3-4): 146-55, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23942583

RESUMO

BACKGROUND: The prevalence and incidence of neurogenic overactive bladder (nOAB) are poorly defined. This systematic literature review identified nOAB epidemiological data and estimated the incidence and prevalence of urinary incontinence (UI) and detrusor overactivity (DO) in patients with multiple sclerosis (MS), spinal cord injury (SCI), Parkinson's disease (PD), stroke and spina bifida. An initial search of MEDLINE, Embase, PubMed, and the Cochrane library was supplemented by an internet search for grey literature and manual searching of the bibliographies of retrieved articles. Additional study selection identified comparable studies for statistical analysis. A descriptive statistical analysis, single-arm meta-analysis and stratified analysis were conducted using predefined criteria. SUMMARY: Initial selection identified 189 articles containing prevalence data. Secondary selection for statistical analysis identified 39 and 52 articles with prevalence of UI and DO, respectively. Random-effect meta-analysis found the prevalence of UI was 50.9% in patients with MS, 52.3% with SCI, 33.1% with PD and 23.6% with stroke. Spina bifida was excluded due to insufficient data. The prevalence of DO may be biased and artificially elevated because it can only be measured with urodynamic investigations. KEY MESSAGES: A substantial proportion of patients with neurological conditions develop UI that may be attributable to nOAB.


Assuntos
Bexiga Urinaria Neurogênica/epidemiologia , Bexiga Urinária Hiperativa/epidemiologia , Incontinência Urinária/epidemiologia , Comorbidade , Humanos , Esclerose Múltipla/epidemiologia , Doença de Parkinson/epidemiologia , Traumatismos da Medula Espinal/epidemiologia , Disrafismo Espinal/epidemiologia , Acidente Vascular Cerebral/epidemiologia
3.
Emerg Med J ; 30(2): 101-5, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22396383

RESUMO

OBJECTIVES: To determine whether patients with elevated creatinine who present to the emergency department (ED) with potential acute coronary syndrome (ACS) are at an increased risk of acute myocardial infarction (AMI) or 30-day cardiovascular (CV) events. METHODS: A secondary analysis of a cohort study of patients presenting to the ED with potential ACS with serum creatinine measurements. Research assistants collected demographics, history, symptoms, hospital course and 30-day follow-up. Outcomes measured were in-hospital AMI and 30-day CV events (death, nonfatal AMI, revascularisation). Prespecified multivariable models included age, gender, race and cardiac risk factors and presenting electrocardiogram (ECG). We used a creatinine cut-off point of 132.6 mmol/l. Data are presented as OR and 95% CI. RESULTS: 3451 patients were enrolled (age, 52.9±13.2; 55% female patients; 64% black patients). There were 120 AMI during initial visit and 232 patients had 30-day CV events (43 deaths, 128 AMI, 120 revascularisations). Creatinine values were normal in 3086 (89.4%) and abnormal in 365 (10.5%) patients. In multivariable models the adjusted OR (95% CI) for the association between abnormal creatinine and AMI was 1.43 (0.88 to 2.30) and 30-day CV events was 1.57 (1.10 to 2.25). The odds of 30-day CV events were increased for patients who were older, male subjects, white, had hyperlipidaemia, hypertension or a history of CAD, or presented with an abnormal ECG. CONCLUSION: In patients with potential ACS in the ED, renal dysfunction predicts a higher likelihood of 30-day CV events, but not an independent predictor after controlling for other risk factors. It appears to be a marker of other CV risks.


Assuntos
Nefropatias/complicações , Infarto do Miocárdio/etiologia , Síndrome Coronariana Aguda/sangue , Adulto , Idoso , Biomarcadores/sangue , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Estudos de Coortes , Creatinina/sangue , Serviço Hospitalar de Emergência/estatística & dados numéricos , Feminino , Humanos , Incidência , Nefropatias/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Infarto do Miocárdio/epidemiologia , Fatores de Risco
4.
Pediatr Nephrol ; 27(5): 813-9, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22116578

RESUMO

BACKGROUND: Conventional immunosuppressive therapy for primary pediatric focal segmental glomerulosclerosis (FSGS) is potentially toxic and only moderate evidence supports its effectiveness. Renin-angiotensin-aldosterone (RAAS) inhibition monotherapy is anecdotally used in selected patients as an alternative to conventional therapy. METHODS: We performed a retrospective cohort study of children with primary FSGS seen at a tertiary care academic hospital between 1986 and 2008. We classified patients into two groups based upon initial treatment: RAAS inhibition monotherapy (RIM) and conventional therapy (CT). The primary endpoint was progression to end-stage renal disease (ESRD). Secondary endpoints were remission of proteinuria, relapse, and death. RESULTS: The cohort consisted of 67 patients. Mean baseline urine protein/creatinine ratio (Up/c) was 8.0 (5.2, 10.7) mg/mg, and mean baseline estimated glomerular filtration rate (eGFR) was 115.0 (101.8, 128.1) mL/min/1.73 m(2). Patients in the RIM group were more likely to have lower eGFR (100.8 mL/min/1.73 m(2) vs 132.9 mL/min/1.73 m(2), p = 0.01) and less proteinuria (4.4 vs.14.4, p < 0.01). Renal failure occurred in 22.9% of the RIM group vs 40.6% in the CT group (log-rank p = 0.07). After adjustment for African-American race, time period of presentation, baseline age, eGFR, and Up/c, patients in the RIM group had a 0.11 hazard ratio of progressing to renal failure compared with patients in the CT group (p < 0.01). CONCLUSIONS: Children treated initially with RIM may have better outcomes than those treated with CT.


Assuntos
Glomerulosclerose Segmentar e Focal/tratamento farmacológico , Sistema Renina-Angiotensina/efeitos dos fármacos , Adolescente , Pressão Sanguínea , Criança , Estudos de Coortes , Feminino , Taxa de Filtração Glomerular , Humanos , Imunossupressores/uso terapêutico , Estimativa de Kaplan-Meier , Testes de Função Renal , Masculino , Proteinúria/etiologia , Insuficiência Renal/etiologia , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
5.
Appl Microbiol Biotechnol ; 95(3): 565-75, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22695801

RESUMO

The USA has proposed that 30 % of liquid transportation fuel be produced from renewable resources by 2030 (Perlack and Stokes 2011). It will be impossible to reach this goal using corn kernel-based ethanol alone. Pectin-rich biomass, an under-utilized waste product of the sugar and juice industry, can augment US ethanol supplies by capitalizing on this already established feedstock. Currently, pectin-rich biomass is sold (at low value) as animal feed. This review focuses on the three most studied types of pectin-rich biomass: sugar beet pulp, citrus waste and apple pomace. Fermentations of these materials have been conducted with a variety of ethanologens, including yeasts and bacteria. Escherichia coli can ferment a wide range of sugars including galacturonic acid, the primary component of pectin. However, the mixed acid metabolism of E. coli can produce unwanted side products. Saccharomyces cerevisiae cannot naturally ferment galacturonic acid nor pentose sugars but has a homoethanol pathway. Erwinia chrysanthemi is capable of degrading many of the cell wall components of pectin-rich materials, including pectin. Klebsiella oxytoca can metabolize a diverse array of sugars including cellobiose, one degradation product of cellulose. However, both E. chrysanthemi and K. oxytoca produce side products during fermentation, similar to E. coli. Using pectin-rich residues from industrial processes is beneficial because the material is already collected and partially pretreated to facilitate enzymatic deconstruction of the plant cell walls. Using biomass already produced for other purposes is an attractive practice because fewer greenhouse gases (GHG) will be anticipated from land-use changes.


Assuntos
Bactérias/metabolismo , Etanol/metabolismo , Fungos/metabolismo , Pectinas/metabolismo , Biomassa , Fermentação , Indústria Alimentícia , Resíduos Industriais
6.
Appl Environ Microbiol ; 77(15): 5184-91, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21666025

RESUMO

Ethanologenic Escherichia coli strain KO11 was sequentially engineered to contain the Klebsiella oxytoca cellobiose phosphotransferase genes (casAB) as well as a pectate lyase (pelE) from Erwinia chrysanthemi, yielding strains LY40A (casAB) and JP07 (casAB pelE), respectively. To obtain an effective secretion of PelE, the Sec-dependent pathway out genes from E. chrysanthemi were provided on a cosmid to strain JP07 to construct strain JP07C. Finally, oligogalacturonide lyase (ogl) from E. chrysanthemi was added to produce strain JP08C. E. coli strains LY40A, JP07, JP07C, and JP08C possessed significant cellobiase activity in cell lysates, while only strains JP07C and JP08C demonstrated extracellular pectate lyase activity. Fermentations conducted by using a mixture of pure sugars representative of the composition of sugar beet pulp (SBP) showed that strains LY40A, JP07, JP07C, and JP08C were able to ferment cellobiose, resulting in increased ethanol production from 15 to 45% in comparison to that of KO11. Fermentations with SBP at very low fungal enzyme loads during saccharification revealed significantly higher levels of ethanol production for LY40A, JP07C, and JP08C than for KO11. JP07C ethanol yields were not considerably higher than those of LY40A; however, oligogalacturonide polymerization studies showed an increased breakdown of biomass to small-chain (degree of polymerization, ≤6) oligogalacturonides. JP08C achieved a further breakdown of polygalacturonate to monomeric sugars, resulting in a 164% increase in ethanol yields compared to those of KO11. The addition of commercial pectin methylesterase (PME) further increased JP08C ethanol production compared to that of LY40A by demethylating the pectin for enzymatic attack by pectin-degrading enzymes.


Assuntos
Biocombustíveis , Biomassa , Escherichia coli/metabolismo , Etanol/metabolismo , Lignina/metabolismo , Pectinas/metabolismo , beta-Glucosidase/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Hidrolases de Éster Carboxílico/farmacologia , Cosmídeos/genética , Dickeya chrysanthemi/genética , Dickeya chrysanthemi/metabolismo , Escherichia coli/genética , Fermentação , Engenharia Genética , Klebsiella oxytoca/genética , Klebsiella oxytoca/metabolismo , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/genética , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/metabolismo , Polissacarídeo-Liases/genética , Polissacarídeo-Liases/metabolismo
7.
Ann Emerg Med ; 58(6): 501-7, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21802776

RESUMO

STUDY OBJECTIVE: Although lay people often assume that severe pain is more commonly associated with worse outcomes, the relationship between pain severity and outcome for patients presenting with potential acute coronary syndrome has not been well described. We hypothesize that pain severity will not be associated with acute myocardial infarction or 30-day cardiovascular complications. METHODS: We conducted a secondary analysis of a prospective cohort study of patients presenting to the emergency department (ED) with potential acute coronary syndrome. Trained research assistants collected data, including demographics, medical history, symptoms, hospital course, and 30-day outcomes (record review and telephone). Pain score on arrival (0 to 10) was abstracted from nurses' triage documentation in the electronic record. Severe pain was defined as 9 or 10. The main outcomes were the prevalence of acute myocardial infarction during index visit and composite of death, acute myocardial infarction, revascularization including percutaneous coronary intervention, or coronary bypass artery grafting at 30 days. Multivariable modeling was prespecified to adjust for age, race, sex, pain duration, thrombolysis in myocardial infarction (TIMI) score, and mode of arrival. Data are presented as relative risk (RR) with 95% confidence intervals (CI). RESULTS: Patients (3,306) had pain documented (mean age 51.0 years; SD 12.6 years; 57% women; 66% black). Follow-up was 93%. By 30 days, 34 patients had died, 105 patients underwent revascularization (94 percutaneous coronary intervention, 14 coronary bypass artery grafting), and 111 patients experienced acute myocardial infarction. There was not a relationship between severe pain and acute myocardial infarction (RR 1.28; 95% CI 0.93 to 1.76) or 30-day composite outcome (1.19; 95% CI 0.91 to 1.56). After adjusting for potential confounding variables, we found that the prevalence of inhospital acute myocardial infarction was related to TIMI score (adjusted relative risk [aRR] 2.00; 95% CI 1.05 to 3.80), male sex (aRR 1.48; 95% CI 1.00 to 2.18), and arrival by emergency medical services (EMS) (aRR 1.73; 95% CI 1.13 to 2.63) but not age (aRR 1.42; 95% CI 0.68 to 2.95), white race (aRR 1.25; 95% CI 0.85 to 1.86), pain duration greater than 1 hour (aRR 1.36; 95% CI 0.89 to 2.07), or severe pain (aRR 1.43; 95% CI 0.91 to 2.22). Thirty-day composite outcome was related to male sex (aRR 1.53; 95% CI 1.16 to 2.01), white race (aRR 1.43; 95% CI 1.09 to 1.87), and higher TIMI score (aRR 2.24; 95% CI 1.39 to 3.60) but was not related to age (aRR 1.26; 95% CI 0.75 to 2.11), pain duration greater than 1 hour (aRR 0.8; 95% CI 0.60 to 1.06), EMS arrival (aRR 1.23; 95% CI 0.96 to 1.60), or severe pain (aRR 1.39; 95% CI 0.95 to 1.97). CONCLUSION: For patients who present to the ED with potential acute coronary syndrome, severe pain is not related to likelihood of acute myocardial infarction at presentation or death, acute myocardial infarction or revascularization within 30 days.


Assuntos
Síndrome Coronariana Aguda/diagnóstico , Dor no Peito/etiologia , Síndrome Coronariana Aguda/complicações , Fatores Etários , Dor no Peito/diagnóstico , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico , Medição da Dor , Prognóstico , Estudos Prospectivos , Risco , Fatores Sexuais
8.
Physiol Plant ; 138(1): 113-21, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20070846

RESUMO

Brief (1-100 min) irradiations with three different ultraviolet-B (UV-B) and ultraviolet-C (UV-C) wave bands induced increases the UV-absorbing pigments extracted from cucumber (Cucumis sativus L.) and Arabidopsis. Spectra of methanol/1% HCl extracts from cucumber hypocotyl segments spanning 250-400 nm showed a single defined peak at 317 nm. When seedlings were irradiated with 5 kJ m(-2) UV-B radiation containing proportionally greater short wavelength UV-B (37% of UV-B between 280 and 300 nm; full-spectrum UV-B, FS-UVB), tissue extracts taken 24 h after irradiation showed an overall increase in absorption (91% increase at 317 nm) with a second defined peak at 263 nm. Irradiation with 1.1 kJ m(-2) UV-C (254 nm) caused similar changes. In contrast, seedlings irradiated with 5 kJ m(-2) UV-B including only wavelengths longer than 290 nm (8% of UV-B between 290 and 300 nm; long-wavelength UV-B, LW-UVB) resulted only in a general increase in absorption (80% at 317 nm). The increases in absorption were detectable as early as 3 h after irradiation with FS-UVB and UV-C, while the response to LW-UVB was first detectable at 6 h after irradiation. In extracts from whole Arabidopsis seedlings, 5 kJ m(-2) LW-UVB caused only a 20% increase in total absorption. Irradiation with 5 kJ m(-2) FS-UVB caused the appearance of a new peak at 270 nm and a concomitant increase in absorption of 72%. The induction of this new peak was observed in seedlings carrying the fah1 mutation which disrupts the pathway for sinapate synthesis. The results are in agreement with previously published data on stem elongation indicating the existence of two response pathways within the UV-B, one operating at longer wavelengths (>300 nm) and another specifically activated by short wavelength UV-B (<300 nm and also by UV-C).


Assuntos
Arabidopsis/efeitos da radiação , Cucumis sativus/efeitos da radiação , Pigmentos Biológicos/análise , Raios Ultravioleta , Absorção , Arabidopsis/crescimento & desenvolvimento , Cucumis sativus/crescimento & desenvolvimento , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação
9.
Elife ; 72018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29313490

RESUMO

As part of the Reproducibility Project: Cancer Biology, we published a Registered Report (Blum et al., 2015), that described how we intended to replicate selected experiments from the paper 'Transcriptional amplification in tumor cells with elevated c-Myc' (Lin et al., 2012). Here we report the results. We found overexpression of c-Myc increased total levels of RNA in P493-6 Burkitt's lymphoma cells; however, while the effect was in the same direction as the original study (Figure 3E; Lin et al., 2012), statistical significance and the size of the effect varied between the original study and the two different lots of serum tested in this replication. Digital gene expression analysis for a set of genes was also performed on P493-6 cells before and after c-Myc overexpression. Transcripts from genes that were active before c-Myc induction increased in expression following c-Myc overexpression, similar to the original study (Figure 3F; Lin et al., 2012). Transcripts from genes that were silent before c-Myc induction also increased in expression following c-Myc overexpression, while the original study concluded elevated c-Myc had no effect on silent genes (Figure 3F; Lin et al., 2012). Treating the data as paired, we found a statistically significant increase in gene expression for both active and silent genes upon c-Myc induction, with the change in gene expression greater for active genes compared to silent genes. Finally, we report meta-analyses for each result.


Assuntos
Linfoma de Burkitt/patologia , Proteínas Proto-Oncogênicas c-myc/análise , Transcrição Gênica , Humanos , Regulação para Cima
10.
ANZ J Surg ; 72(9): 655-9, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12269918

RESUMO

INTRODUCTION: Accurate staging of the axilla for metastatic disease is critical in deciding on the optimal management of patients with breast cancer. Lymph node status is the most powerful prognostic factor. Current standard surgical management of breast cancer involves axillary dissection for staging. Pathological staging by routine histology, however, is known to understage the disease extent because only one or two sections are taken from each node, a sampling of less than 1% of most nodes. Sentinel node biopsy is currently under trial to determine if thorough pathological staging of the most likely involved node is more accurate than standard pathological assessment of all nodes. The present pilot study was undertaken to investigate an alternative method of assessing all axillary nodes for cancer cells. METHODS: After routine material was taken from lymph nodes for standard pathological assessment, discarded parts of nodes were used for the study technique. These node parts were mechanically disaggregated, and the cell suspension centrifuged on a density gradient to separate any tumour cells (into the pellet) from lymphocytes (at the top of the gradient). The pellet was then assessed by haematoxylin and eosin and immunohistochemistry. RESULTS: The results of the present study proved highly significant. The technique detected metastatic cells in three nodes which were negative on routine pathology, in one case changing the status of the patient from node-negative to node-positive. DISCUSSION: It is concluded that the technique examined in the present paper has the potential to reduce sampling error, may offer far more accurate axillary staging than routine histopathology, and should be further evaluated in a controlled trial.


Assuntos
Neoplasias da Mama/patologia , Estadiamento de Neoplasias/métodos , Axila/patologia , Separação Celular , Feminino , Humanos , Metástase Linfática/diagnóstico , Projetos Piloto
11.
Acad Emerg Med ; 17(12): 1322-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21122014

RESUMO

Patient-centered care is defined by the Institute of Medicine (IOM) as care that is responsive to individual patient needs and values and that guides the treatment decisions. This article is a result of a breakout session of the 2010 Academic Emergency Medicine (AEM) consensus conference and describes the process of developing consensus-based recommendations for providing patient-centered emergency care. The objectives of the working group were to identify and describe the critical gaps in the provision of patient-centered care, develop a consensus-based research agenda, and create a list of future research priorities. Using e-mail and in-person meetings, knowledge gaps were identified in the areas of respect for patient preferences, coordination of clinical care, and communication among health care providers. Four consensus-based recommendations were developed on the following themes: enhancing communication and patient advocacy in emergency departments (EDs), facilitating care coordination after discharge, defining metrics for patient-centered care, and placing the locus of control of medical information into patients' hands. The set of research priorities based on these recommendations was created to promote research and advance knowledge in this dimension of clinical care.


Assuntos
Serviços Médicos de Emergência/métodos , Assistência Centrada no Paciente , Relações Profissional-Paciente , Área Programática de Saúde , Registros Eletrônicos de Saúde , Prioridades em Saúde , Acessibilidade aos Serviços de Saúde , Humanos , Comunicação Interdisciplinar , National Academies of Science, Engineering, and Medicine, U.S., Health and Medicine Division , Defesa do Paciente , Pesquisa , Estados Unidos
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