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1.
PLoS Genet ; 16(11): e1009200, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33137105

RESUMO

Lateral gene transfer (LGT) has impacted prokaryotic genome evolution, yet the extent to which LGT compromises vertical evolution across individual genes and individual phyla is unknown, as are the factors that govern LGT frequency across genes. Estimating LGT frequency from tree comparisons is problematic when thousands of genomes are compared, because LGT becomes difficult to distinguish from phylogenetic artefacts. Here we report quantitative estimates for verticality across all genes and genomes, leveraging a well-known property of phylogenetic inference: phylogeny works best at the tips of trees. From terminal (tip) phylum level relationships, we calculate the verticality for 19,050,992 genes from 101,422 clusters in 5,655 prokaryotic genomes and rank them by their verticality. Among functional classes, translation, followed by nucleotide and cofactor biosynthesis, and DNA replication and repair are the most vertical. The most vertically evolving lineages are those rich in ecological specialists such as Acidithiobacilli, Chlamydiae, Chlorobi and Methanococcales. Lineages most affected by LGT are the α-, ß-, γ-, and δ- classes of Proteobacteria and the Firmicutes. The 2,587 eukaryotic clusters in our sample having prokaryotic homologues fail to reject eukaryotic monophyly using the likelihood ratio test. The low verticality of α-proteobacterial and cyanobacterial genomes requires only three partners-an archaeal host, a mitochondrial symbiont, and a plastid ancestor-each with mosaic chromosomes, to directly account for the prokaryotic origin of eukaryotic genes. In terms of phylogeny, the 100 most vertically evolving prokaryotic genes are neither representative nor predictive for the remaining 97% of an average genome. In search of factors that govern LGT frequency, we find a simple but natural principle: Verticality correlates strongly with gene distribution density, LGT being least likely for intruding genes that must replace a preexisting homologue in recipient chromosomes. LGT is most likely for novel genetic material, intruding genes that encounter no competing copy.


Assuntos
Archaea/genética , Bactérias/genética , Evolução Molecular , Transferência Genética Horizontal , Genoma Arqueal/genética , Genoma Bacteriano/genética , Filogenia
2.
Br J Cancer ; 122(12): 1760-1768, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32350413

RESUMO

BACKGROUND: Nab-paclitaxel plus gemcitabine (nabP+gemcitabine) offers modest survival gains for patients with metastatic pancreatic ductal adenocarcinoma (PDAC). Sequential scheduling of nabP+gemcitabine in a PDAC mouse model improved efficacy; this hypothesis was tested in a clinical trial. METHODS: Patients with previously untreated metastatic PDAC were randomised to receive nabP+gemcitabine administered either concomitantly on the same day, or sequentially, with gemcitabine administered 24 h after nabP. The primary outcome measure was progression-free survival (PFS). Secondary outcome measures were objective response rate (ORR), overall survival (OS), safety, quality of life (QoL) and predictive biomarkers. RESULTS: In total, 71 patients received sequential (SEQ) and 75 concomitant (CON) treatment. Six-month PFS was 46% with SEQ and 32% with CON scheduling. Median PFS (5.6 versus 4.0 months, hazard ratio [HR] 0.67, 95% confidence interval [95% CI] 0.47-0.95, p = 0.022) and ORR (52% versus 31%, p = 0.023) favoured the SEQ arm; median OS was 10.2 versus 8.2 months (HR 0.93, 95% CI 0.65-1.33, p = 0.70). CTCAE Grade ≥3 neutropaenia incidence doubled with SEQ therapy but was not detrimental to QoL. Strongly positive tumour epithelial cytidine deaminase (CDA) expression favoured benefit from SEQ therapy (PFS HR 0.31, 95% CI 0.13-0.70). CONCLUSIONS: SEQ delivery of nabP+gemcitabine improved PFS and ORR, with manageable toxicity, but did not significantly improve OS. CLINICAL TRIAL REGISTRATION: ISRCTN71070888; ClinialTrials.gov (NCT03529175).


Assuntos
Albuminas/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Desoxicitidina/análogos & derivados , Paclitaxel/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/mortalidade , Desoxicitidina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Intervalo Livre de Progressão , Gencitabina , Neoplasias Pancreáticas
3.
Br J Cancer ; 116(10): 1264-1270, 2017 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-28376080

RESUMO

BACKGROUND: SCALOP, a randomised, phase II trial, tested the activity and safety of gemcitabine (GEM)-based and capecitabine (CAP)-based chemoradiation (CRT) for locally advanced pancreatic cancer (LAPC). Here we present the long-term outcomes. METHODS: Eligibility: histologically proven LAPC ⩽7 cm. Following 12 weeks of induction GEMCAP chemotherapy (three cycles: GEM 1000 mg m-2 days 1, 8, 15; CAP 830 mg m-2 days 1-21 q28 days) patients with stable/responding disease, tumour ⩽6 cm, and WHO Performance Status 0-1 were randomised to receive one cycle GEMCAP followed by CAP (830 mg m-2 b.d. on weekdays only) or GEM (300 mg m-2 weekly) with radiation (50.4 Gy per 28 fractions). RESULTS: One-hundred fourteen patients (28 UK centres) were registered between 24 December 2009 and 25 October 2011, and 74 were randomised (CAP-RT=36; GEM-RT=38). At the time of this analysis, 105 of the 114 patients had died and the surviving 9 patients had been followed up for a median of 10.9 months (IQR: 2.9-18.7). Updated median OS was 17.6 months (95% CI: 14.6-22.7) in the CAP-CRT arm and 14.6 months (95% CI: 11.1-16.0) in the GEM-CRT arm (intention-to-treat adjusted hazard ratio (HR): 0.68 (95% CI: 0.38-1.21, P=0.185)); median progression-free survival (PFS) was 12.0 months (95% CI: 10.0-15.2) in the CAP-CRT arm and 10.4 months (95% CI: 8.8-12.7) in the GEM-CRT arm (intention-to-treat adjusted HR: 0.60 (95% CI: 0.32-1.14, P=0.120)). In baseline multivariable model, age ⩾65 years, better performance status, CA19.9<613 IU l-1, and shorter tumour diameter predicted improved OS. CAP-CRT, age ⩾65 years, better performance status, CA19.9 <46 IU ml-1 predicted improved OS and PFS in the pre-radiotherapy model. Nine-month PFS was highly predictive of OS. CONCLUSIONS: CAP-CRT remains the superior regimen. SCALOP showed that patients with CA19.9 <46 IU ml-1 after induction chemotherapy are more likely to benefit from CRT.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Antígeno CA-19-9/sangue , Quimiorradioterapia , Neoplasias Pancreáticas/terapia , Idoso , Capecitabina/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Fracionamento da Dose de Radiação , Feminino , Seguimentos , Humanos , Quimioterapia de Indução/métodos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/patologia , Curva ROC , Índice de Gravidade de Doença , Taxa de Sobrevida , Fatores de Tempo , Carga Tumoral , Gencitabina
4.
Br J Cancer ; 116(6): 709-716, 2017 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-28196063

RESUMO

BACKGROUND: The SCOPE-1 study tested the role of adding cetuximab to conventional definitive chemoradiotherapy (dCRT), and demonstrated greater toxicity and worse survival outcomes. We present the long-term outcomes and patterns of recurrence. METHODS: SCOPE-1 was a phase II/III trial in which patients were randomised to cisplatin 60 mg m-2 (day 1) and capecitabine 625 mg m-2 bd (days 1-21) for four cycles +/- cetuximab 400 mg m-2 day 1 then by 250 mg m-2 weekly. Radiotherapy consisted of 50 Gy/25# given concurrently with cycles 3 and 4. Recruitment was between February 2008 and February 2012, when the IDMC recommended closure on the basis of futility. RESULTS: About 258 patients (dCRT=129; dCRT+cetuximab (dCRT+C)=129) were recruited from 36 centres. About 72.9% (n=188) had squamous cell histology. The median follow-up (IQR) was 46.2 (35.9-48.3) months for surviving patients. The median overall survival (OS; months; 95% CI) was 34.5 (24.7-42.3) in dCRT and 24.7 (18.6-31.3) in dCRT+C (hazard ratio (HR)=1.25, 95% CIs: 0.93-1.69, P=0.137). Median progression-free survival (PFS; months; 95% CI) was 24.1 (15.3-29.9) and 15.9 (10.7-20.8) months, respectively (HR=1.28, 95% CIs: 0.94-1.75; P=0.114). On multivariable analysis only earlier stage, full-dose RT, and higher cisplatin dose intensity were associated with improved OS. CONCLUSIONS: The mature analysis demonstrates that the dCRT regimen used in the study provided useful survival outcomes despite its use in patients who were largely unfit for surgery or who had inoperable disease. Given the competing risk of systemic and local failure, future studies should continue to focus on enhancing local control as well as optimising systemic therapy.


Assuntos
Adenocarcinoma/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/terapia , Quimiorradioterapia , Neoplasias Esofágicas/terapia , Recidiva Local de Neoplasia/terapia , Adenocarcinoma/patologia , Idoso , Capecitabina/administração & dosagem , Carcinoma de Células Escamosas/patologia , Cetuximab/administração & dosagem , Cisplatino/administração & dosagem , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Masculino , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida
5.
Tech Coloproctol ; 20(10): 683-93, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27510524

RESUMO

BACKGROUND: The optimal time of rectal resection after long-course chemoradiotherapy (CRT) remains unclear. A feasibility study was undertaken for a multi-centre randomized controlled trial evaluating the impact of the interval after chemoradiotherapy on the technical complexity of surgery. METHODS: Patients with rectal cancer were randomized to either a 6- or 12-week interval between CRT and surgery between June 2012 and May 2014 (ISRCTN registration number: 88843062). For blinded technical complexity assessment, the Observational Clinical Human Reliability Analysis technique was used to quantify technical errors enacted within video recordings of operations. Other measured outcomes included resection completeness, specimen quality, radiological down-staging, tumour cell density down-staging and surgeon-reported technical complexity. RESULTS: Thirty-one patients were enrolled: 15 were randomized to 6 and 16-12 weeks across 7 centres. Fewer eligible patients were identified than had been predicted. Of 23 patients who underwent resection, mean 12.3 errors were observed per case at 6 weeks vs. 10.7 at 12 weeks (p = 0.401). Other measured outcomes were similar between groups. CONCLUSIONS: The feasibility of measurement of operative performance of rectal cancer surgery as an endpoint was confirmed in this exploratory study. Recruitment of sufficient numbers of patients represented a challenge, and a proportion of patients did not proceed to resection surgery. These results suggest that interval after CRT may not substantially impact upon surgical technical performance.


Assuntos
Quimiorradioterapia/métodos , Colectomia/métodos , Terapia Neoadjuvante/métodos , Neoplasias Retais/terapia , Tempo para o Tratamento , Idoso , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
6.
Br J Cancer ; 113(4): 603-10, 2015 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-26203761

RESUMO

BACKGROUND: Limited data describe patient-reported outcomes (PROs) of localised oesophageal cancer treated with definitive chemoradiotherapy(CRT). The phase 2/3 SCOPE-1 trial assessed the effectiveness of CRT±cetuximab. The trial for the first time provided an opportunity to describe PROs from a multi-centre group of patients treated with CRT that are presented here. METHODS: Patients undergoing CRT±cetuximab within the SCOPE-1 trial (258 patients from 36 UK centres) completed generic-, disease- and treatment-specific health-related quality of life (HRQL) questionnaires (EORTC QLQ-C30, QLQ-OES18, Dermatology Life-Quality Index (DLQI)) at baseline and at 7, 13, 24, 52 and 104 weeks. Mean EORTC functional scale scores (>15 point change significant), DLQI scores (>4 point change significant) and proportions of patients (>15% significant) with 'minimal' or 'severe' symptoms are presented. RESULTS: Questionnaire response rates were good. At baseline, EORTC functional scores were high (>75%) and few symptoms were reported except for severe problems with fatigue, insomnia and eating-related symptoms (e.g., appetite loss, dysphagia, dry mouth) in both groups(>15%). Functional aspects of health deteriorated and symptoms increased with treatment and by week 13 global quality of life, physical, role and social function significantly deteriorated and more problems with fatigue, dyspnoea, appetite loss and trouble with taste were reported. Recovery occurred by 6 months (except severe fatigue and insomnia in >15% of patients) and maintained at follow-up with no differences between groups. CONCLUSIONS: CRT for localised oesophageal cancer has a significant detrimental impact on many aspects of HRQL; however, recovery is achieved by 6 months and maintained with the exception of persisting problems with severe fatigue and insomnia. The data suggest that the HRQL recovery after definitive CRT is quicker, and there is little lasting deficit compared with treatment including surgery. These data need to be compared with HRQL data from studies evaluating treatments including surgery for oesophageal cancer.


Assuntos
Neoplasias Esofágicas/terapia , Anticorpos Monoclonais Humanizados/uso terapêutico , Cetuximab , Quimiorradioterapia/métodos , Humanos , Avaliação de Resultados da Assistência ao Paciente , Qualidade de Vida , Inquéritos e Questionários
7.
Dis Esophagus ; 28(2): 156-63, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24438540

RESUMO

Accurate evaluation of radical radiotherapy requires well designed research with valid and appropriate outcomes. This study reviewed standards of outcome reporting and study design in randomized controlled trials (RCTs) of radiation-based therapy for esophageal cancer and made recommendations for future work. Randomized controlled trials reporting outcomes of definitive radiation-based treatment alone or in combination with chemotherapy were systematically identified and summarized. The types, frequency, and definitions of all clinical and patient-reported outcomes (PROs) reported in the methods and results sections of papers were examined. Studies providing a definition for at least one outcome and presenting all outcomes reported in the methods were classified as high quality. From 1425 abstracts, 16 RCTs including 1803 patients were identified. The primary outcome was overall survival in 13 studies, but five different definitions were reported. Outcomes for treatment failure included local, regional, and distant failures, and inconsistent definitions were applied. An observer assessment of dysphagia was reported in seven RCTs but PROs were reported in only one. Only three RCTs were at low risk of bias, with all lacking reports of sequence generation and only a minority reporting allocation concealment. The quality of outcome reporting in RCTs was inconsistent and risked bias. A core outcome set including clinical and PROs is needed to improve reporting of trials of definitive radiation-based treatment for esophageal cancer.


Assuntos
Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/mortalidade , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
8.
Br J Cancer ; 111(2): 234-40, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24921919

RESUMO

BACKGROUND: The optimal treatment for localised oesophageal squamous cell carcinoma (SCC) is uncertain. We assessed the feasibility of an RCT comparing neoadjuvant treatment and surgery with definitive chemoradiotherapy. METHODS: A feasibility RCT in three centres examined incident patients and reasons for ineligibility using multi-disciplinary team meeting records. Eligible patients were offered participation in the RCT with integrated qualitative research involving audio-recorded recruitment appointments and interviews with patients to inform recruitment training for staff. RESULTS: Of 375 patients with oesophageal SCC, 42 (11.2%) were eligible. Reasons for eligibility varied between centres, with significantly differing proportions of patients excluded because of total tumour length (P=0.002). Analyses of audio-recordings and patient interviews showed that recruiters had challenges articulating the trial design in simple terms, balancing treatment arms and explaining the need for randomisation. Before analyses of the qualitative data and recruiter training no patients were randomised. Following training in one centre 5 of 16 eligible patients were randomised. CONCLUSIONS: An RCT of surgical vs non-surgical treatment for SCC of the oesophagus is not feasible in the UK alone because of the low number of incident eligible patients. A trial comparing diverse treatment approaches may be possible with investment to support the recruitment process.


Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Capecitabina , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/cirurgia , Quimiorradioterapia , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/cirurgia , Carcinoma de Células Escamosas do Esôfago , Estudos de Viabilidade , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Masculino , Terapia Neoadjuvante , Projetos Piloto , Resultado do Tratamento
9.
FEBS Lett ; 598(14): 1692-1714, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38750628

RESUMO

Molecular oxygen is a stable diradical. All O2-dependent enzymes employ a radical mechanism. Generated by cyanobacteria, O2 started accumulating on Earth 2.4 billion years ago. Its evolutionary impact is traditionally sought in respiration and energy yield. We mapped 365 O2-dependent enzymatic reactions of prokaryotes to phylogenies for the corresponding 792 protein families. The main physiological adaptations imparted by O2-dependent enzymes were not energy conservation, but novel organic substrate oxidations and O2-dependent, hence O2-tolerant, alternative pathways for O2-inhibited reactions. Oxygen-dependent enzymes evolved in ancestrally anaerobic pathways for essential cofactor biosynthesis including NAD+, pyridoxal, thiamine, ubiquinone, cobalamin, heme, and chlorophyll. These innovations allowed prokaryotes to synthesize essential cofactors in O2-containing environments, a prerequisite for the later emergence of aerobic respiratory chains.


Assuntos
Oxigênio , Oxigênio/metabolismo , Aerobiose , Filogenia , Células Procarióticas/metabolismo , Evolução Molecular , Oxirredução , Enzimas/metabolismo , Enzimas/genética
10.
Science ; 383(6688): eadj9223, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484069

RESUMO

Humans, like all mammals, depend on the gut microbiome for digestion of cellulose, the main component of plant fiber. However, evidence for cellulose fermentation in the human gut is scarce. We have identified ruminococcal species in the gut microbiota of human populations that assemble functional multienzymatic cellulosome structures capable of degrading plant cell wall polysaccharides. One of these species, which is strongly associated with humans, likely originated in the ruminant gut and was subsequently transferred to the human gut, potentially during domestication where it underwent diversification and diet-related adaptation through the acquisition of genes from other gut microbes. Collectively, these species are abundant and widespread among ancient humans, hunter-gatherers, and rural populations but are rare in populations from industrialized societies thus indicating potential disappearance in response to the westernized lifestyle.


Assuntos
Celulose , Fibras na Dieta , Microbioma Gastrointestinal , Ruminococcus , Humanos , Celulose/metabolismo , Microbioma Gastrointestinal/genética , Microbioma Gastrointestinal/fisiologia , Ruminococcus/classificação , Ruminococcus/enzimologia , Ruminococcus/genética , Fibras na Dieta/metabolismo , Filogenia , Desenvolvimento Industrial
11.
Br J Cancer ; 108(11): 2399-406, 2013 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-23652303

RESUMO

BACKGROUND: Women treated with supradiaphragmatic radiotherapy (sRT) for Hodgkin lymphoma (HL) at young ages have a substantially increased breast cancer risk. Little is known about how menarcheal and reproductive factors modify this risk. METHODS: We examined the effects of menarcheal age, pregnancy, and menopausal age on breast cancer risk following sRT in case-control data from questionnaires completed by 2497 women from a cohort of 5002 treated with sRT for HL at ages <36 during 1956-2003. RESULTS: Two-hundred and sixty women had been diagnosed with breast cancer. Breast cancer risk was significantly increased in patients treated within 6 months of menarche (odds ratio (OR) 5.52, 95% confidence interval (CI) (1.97-15.46)), and increased significantly with proximity of sRT to menarche (Ptrend<0.001). It was greatest when sRT was close to a late menarche, but based on small numbers and needing reexamination elsewhere. Risk was not significantly affected by full-term pregnancies before or after treatment. Risk was significantly reduced by early menopause (OR 0.55, 95% CI (0.35-0.85)), and increased with number of premenopausal years after treatment (Ptrend=0.003). CONCLUSION: In summary, this paper shows for the first time that sRT close to menarche substantially increases breast cancer risk. Careful consideration should be given to follow-up of these women, and to measures that might reduce their future breast cancer risk.


Assuntos
Neoplasias da Mama/epidemiologia , Doença de Hodgkin/radioterapia , Neoplasias Induzidas por Radiação/epidemiologia , Adulto , Fatores Etários , Neoplasias da Mama/etiologia , Estudos de Casos e Controles , Estudos de Coortes , Inglaterra/epidemiologia , Feminino , Humanos , Menarca , Pessoa de Meia-Idade , Neoplasias Induzidas por Radiação/etiologia , Gravidez , História Reprodutiva , País de Gales/epidemiologia
12.
Ann Oncol ; 24(3): 702-9, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23108952

RESUMO

BACKGROUND: Peri-operative chemotherapy and surgery is a standard treatment of localised oesophagogastric adenocarcinoma; however, the outcomes remain poor. PATIENTS AND METHODS: ST03 is a multicentre, randomised, phase II/III study comparing peri-operative ECX with or without bevacizumab (ECX-B). The primary outcome measure of phase II (n = 200) was safety, specifically gastrointestinal (GI) perforation rates and cardiotoxicity. RESULTS: Two hundred patients were randomised between October 2007 and April 2010. Ninety-one/101 (90%) ECX and 86/99 (87%) ECX-B patients completed pre-operative chemotherapy; 7 ECX and 9 ECX-B patients stopped due to toxicity. Gastrointestinal perforations (3 ECX, 1 ECX-B), cardiac events (1 ECX, 4 ECX-B) and venous thromboembolic events (VTEs, 8 ECX, 7 ECX-B) were uncommon. Arterial thromboembolic events (ATEs, myocardial infarction (MI) or cerebrovascular accident) were more frequent with ECX-B (5 versus 1 with ECX). Delayed wound healing, anastomotic leaks and GI bleeding rates were similar. More asymptomatic left ventricular ejection fraction (LVEF) falls (≥15% and/or to <50%) occurred with ECX-B (21.2% versus 11.1% with ECX). Clinically significant falls (≥10% to below lower limit of normal, LLN) occurred in (15.3%) and (8.9%) respectively, with no associated cardiac failure (median 22 months follow-up). CONCLUSIONS: Addition of bevacizumab to peri-operative ECX chemotherapy is feasible with acceptable toxicity and no negative impact on surgical outcomes.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Gástricas/tratamento farmacológico , Adenocarcinoma/cirurgia , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Bevacizumab , Capecitabina , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Epirubicina/administração & dosagem , Neoplasias Esofágicas/cirurgia , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/análogos & derivados , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/induzido quimicamente , Infarto do Miocárdio/fisiopatologia , Neoplasias Gástricas/cirurgia , Volume Sistólico/efeitos dos fármacos , Tromboembolia/induzido quimicamente , Tromboembolia/fisiopatologia , Resultado do Tratamento
13.
Eur Rev Med Pharmacol Sci ; 27(21): 10563-10568, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37975380

RESUMO

OBJECTIVE: This study aimed to determine the bacteriological profile of childhood acute bacterial meningitis in Pakistan. PATIENTS AND METHODS: The study included a total of 100 children aged between 1 month and 5 years, who were admitted with a diagnosis of meningitis based on clinical findings and positive cerebrospinal fluid (CSF) tests. Out of the 100 CSF samples collected, 21 isolates were confirmed to contain Enterobacteriaceae. The most prevalent Enterobacteriaceae species were Pseudomonas (n=8, 38.09%), Klebsiella (n=4, 19.04%), E. coli (n=4, 19.04%), and Acinetobacter (n=4, 19.04%), while Citrobacter (n=1, 4.76%) was less common. Antibiotic susceptibility patterns were analyzed for these isolates. RESULTS: Pseudomonas (n=8) exhibited 25% resistance to cefepime and 38% resistance to imipenem. Klebsiella (n=4) showed 75% resistance to imipenem. Acinetobacter (n=4) demonstrated 50% resistance to imipenem, along with varying resistance to cefepime, amikacin, ciprofloxacin, and gentamicin. E. coli (n=4) showed 0% resistance to imipenem and amikacin. However, Citrobacter (n=1) showed 0% resistance to ciprofloxacin, aztreonam, gentamicin, amikacin, levofloxacin, and cefepime. Acute bacterial meningitis primarily affects children under 1 year of age. CONCLUSIONS: CSF culture revealed that Gram-negative bacteria, specifically Pseudomonas spp., were the predominant pathogens in this family based on Pakistani data.


Assuntos
Antibacterianos , Meningites Bacterianas , Criança , Recém-Nascido , Humanos , Lactente , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Enterobacteriaceae , Cefepima , Amicacina , Escherichia coli , Centros de Atenção Terciária , Imipenem , Bactérias Gram-Negativas , Ciprofloxacina , Gentamicinas , Meningites Bacterianas/diagnóstico , Meningites Bacterianas/tratamento farmacológico , Testes de Sensibilidade Microbiana , Farmacorresistência Bacteriana
14.
Arch Environ Contam Toxicol ; 62(4): 696-703, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22108952

RESUMO

Approximately 15,000 tons of wild boar meats (Sus scrofa) are consumed per year in Germany. Boar meat therefore plays a definite role in regard to human diet. Because they are omnivores and because of their high body fat quotient, wild boar may accumulate large concentrations of persistent organic compounds, such as halogenated hydrocarbons, and could thus possibly serve as bioindicators for persistent xenobiotics. In addition, consumption of wild boar meat and liver could lead to increased contaminant levels in humans. Between 2007 and 2009, we tested a total of 529 livers and 506 muscle tissue samples from wild boar for the presence of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). PFOA concentrations ≤45 µg/kg and PFOS concentrations ≤1,780 µg/kg were detected in the liver samples. PFOA concentrations ≤7.4 µg/kg and PFOS concentrations ≤28.6 µg/kg were detected in muscle tissue. Our results show that PFOS may be detected in considerably greater concentrations than PFOA in organs and tissues, which is in agreement with results from other published studies. The comparisons between both organs for the same substance, as well as the comparisons between the substances within an organ, showed clear and statistically significant differences at P < 0.0001. Assuming a tolerable daily intake value of PFOA (1.5 µg/kg bw/d) and PFOS (0.15 µg/kg bw/d) as recommended by the European Food Safety Authority, the results of model calculations based on the maximum concentrations of PFOA and PFOS found in wild boar indicate that there should be no PFC-related health danger resulting from moderate consumption of wild boar meat or liver.


Assuntos
Ácidos Alcanossulfônicos/análise , Caprilatos/análise , Fluorocarbonos/análise , Contaminação de Alimentos , Fígado/química , Músculos/química , Sus scrofa , Animais , Alemanha , Política Nutricional , Medição de Risco
15.
Clin Transl Radiat Oncol ; 28: 24-31, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33748440

RESUMO

BACKGROUND: The RAS/RAF/MEK/ERK signalling pathway has a pivotal role in cancer proliferation and modulating treatment response. Selumetinib inhibits MEK and enhances effects of radiotherapy in preclinical studies. PATIENTS AND METHODS: Single-arm, single-centre, open-label phase I trial. Patients with stage III NSCLC unsuitable for concurrent chemo-radiotherapy, or stage IV with dominant thoracic symptoms, were recruited to a dose-finding stage (Fibonacci 3 + 3 design; maximum number = 18) then an expanded cohort (n = 15). Oral selumetinib was administered twice daily (starting dose 50 mg) commencing 7 days prior to thoracic radiotherapy, then with radiotherapy (6-6.5 weeks; 60-66 Gy/30-33 fractions). The primary objective was to determine the recommended phase II dose (RP2D) of selumetinib in combination with thoracic radiotherapy. RESULTS: 21 patients were enrolled (06/2010-02/2015). Median age: 62y (range 50-73). M:F ratio 12(57%):9(43%). ECOG PS 0:1, 7(33%):14(67%). Stage III 16(76%); IV 5(24%). Median GTV 64 cm3 (range 1-224 cm3). 15 patients comprised the expanded cohort at starting dose. All 21 patients completed thoracic radiotherapy as planned and received induction chemotherapy. 13 (62%) patients received the full dose of selumetinib.In the starting cohort no enhanced radiotherapy-related toxicity was seen. Two patients had dose-limiting toxicity (1x grade 3 diarrhoea/fatigue and 1x pulmonary embolism). Commonest grade 3-4 adverse events: lymphopaenia (19/21 patients) and hypertension (7/21 patients). One patient developed grade 3 oesophagitis. No patients developed grade ≥3 radiation pneumonitis. Two patients were alive at the time of analysis (24 and 26 months follow-up, respectively). Main cause of first disease progression: distant metastases ± locoregional progression (12/21 [57.1%] patients). Six patients had confirmed/suspected pneumocystis jiroveci pneumonia. CONCLUSION: We report poor outcome and severe lymphopenia in most patients treated with thoracic radiotherapy and selumetinib at RP2D in combination, contributing to confirmed/clinically suspected pneumocystis jiroveci pneumonia. These results suggest that this combination should not be pursued in a phase II trial.ClinicalTrials.gov reference: NCT01146756.

16.
Genome Biol Evol ; 13(5)2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33739376

RESUMO

The last eukaryote common ancestor (LECA) possessed mitochondria and all key traits that make eukaryotic cells more complex than their prokaryotic ancestors, yet the timing of mitochondrial acquisition and the role of mitochondria in the origin of eukaryote complexity remain debated. Here, we report evidence from gene duplications in LECA indicating an early origin of mitochondria. Among 163,545 duplications in 24,571 gene trees spanning 150 sequenced eukaryotic genomes, we identify 713 gene duplication events that occurred in LECA. LECA's bacterial-derived genes include numerous mitochondrial functions and were duplicated significantly more often than archaeal-derived and eukaryote-specific genes. The surplus of bacterial-derived duplications in LECA most likely reflects the serial copying of genes from the mitochondrial endosymbiont to the archaeal host's chromosomes. Clustering, phylogenies and likelihood ratio tests for 22.4 million genes from 5,655 prokaryotic and 150 eukaryotic genomes reveal no evidence for lineage-specific gene acquisitions in eukaryotes, except from the plastid in the plant lineage. That finding, and the functions of bacterial genes duplicated in LECA, suggests that the bacterial genes in eukaryotes are acquisitions from the mitochondrion, followed by vertical gene evolution and differential loss across eukaryotic lineages, flanked by concomitant lateral gene transfer among prokaryotes. Overall, the data indicate that recurrent gene transfer via the copying of genes from a resident mitochondrial endosymbiont to archaeal host chromosomes preceded the onset of eukaryotic cellular complexity, favoring mitochondria-early over mitochondria-late hypotheses for eukaryote origin.


Assuntos
Evolução Biológica , Eucariotos/genética , Duplicação Gênica , Mitocôndrias/genética , Evolução Molecular , Transferência Genética Horizontal , Genes Arqueais , Genes Bacterianos
18.
Br J Cancer ; 101(4): 621-7, 2009 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-19672264

RESUMO

BACKGROUND: We assessed the activity of gemcitabine (G) and cisplatin/gemcitabine (C/G) in patients with locally advanced (LA) or metastatic (M) (advanced) biliary cancers (ABC) for whom there is no standard chemotherapy. METHODS: Patients, aged > or =18 years, with pathologically confirmed ABC, Karnofsky performance (KP) > or =60, and adequate haematological, hepatic and renal function were randomised to G 1000 mg m(-2) on D1, 8, 15 q28d (Arm A) or C 25 mg m(-2) followed by G 1000 mg m(-2) D1, 8 q21d (Arm B) for up to 6 months or disease progression. RESULTS: In total, 86 patients (A/B, n=44/42) were randomised between February 2002 and May 2004. Median age (64/62.5 years), KP, primary tumour site, earlier surgery, indwelling biliary stent and disease stage (LA: 25/38%) are comparable between treatment arms. Grade 3-4 toxicity included (A/B, % patients) anaemia (4.5/2.4), leukopenia (6.8/4.8), neutropenia (13.6/14.3), thrombocytopenia (9.1/11.9), lethargy (9.1/28.6), nausea/vomiting (0/7.1) and anorexia (2.3/4.8). Responses (WHO criteria, % of evaluable patients: A n=31 vs B n=36): no CRs; PR 22.6 vs 27.8%; SD 35.5 vs 47.1% for a tumour control rate (CR+PR+SD) of 58.0 vs 75.0%. The median TTP and 6-month progression-free survival (PFS) (the primary end point) were greater in the C/G arm (4.0 vs 8.0 months and 45.5 vs 57.1% in arms A and B, respectively). CONCLUSION: Both regimens seem active in ABC. C/G is associated with an improved tumour control rate, TTP and 6-month PFS. The study has been extended (ABC-02 study) and powered to determine the effect on overall survival and the quality of life.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias do Sistema Biliar/tratamento farmacológico , Colangiocarcinoma/tratamento farmacológico , Cisplatino/administração & dosagem , Desoxicitidina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Desoxicitidina/administração & dosagem , Desoxicitidina/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Gencitabina
20.
J Clin Invest ; 59(5): 786-93, 1977 May.
Artigo em Inglês | MEDLINE | ID: mdl-16037

RESUMO

Tubular fluid flow, urine osmolality, and pH were selectively altered to determine the relative protective roles of these factors in a rat model of acute urate nephrophathy. Various prehyper uricemic conditions were established in five groups of animals: (a) normopenic Wistar rats given no pretreatment (Group I); (b) Wistar rats given acetazolamide, 20 mg/kg, and isotonic NaHCO3 to produce urine alkalinization (Group II); (c) Wistar rats in which a moderate diuresis, similar to that observed in Group II but without urine alkalinization, was induced with furosemide, 2 mg/kg (Group III); (d) Wistar rats in which a high-flow solute diuresis was induced with furosemide, 15 mg/kg (Group IV); (e) Brattleboro rats, homozygous for pituitary diabetes insipidus, that had a spontaneous high-flow water diuresis (Group V). A comparable level of hyperuricemia (19.4+/-2.2 mg/100 ml) was achieved in all animals with intravenous urate infusion. Clearance and micropuncture studies were performed before and 1 h after induction of hyperuicemia. Group I rats had mean falls in renal plasma flow and glomerular filtration rate of 83 and 86%, respectively; nephron filtration rate decreased 66%, and tubular and microvascular pressures increased twofold. In Group II there were 45 and 47% declines in renal plasma flow and glomerular filtration rate, respectively, a 66% fall in nephron filtration rate, and a 30% increase in tubular and vascular pressures. Moderate amounts of urate were seen in the kidneys. Group III had changes in renal function identical to Group II suggesting that the moderate prehyperuricemic diuresis in the latter group and not urine alkalinization produced the partial protection observed. Groups IV and V were completely and comparably protected with renal function studies unchanged from controls. It is concluded that high tubular fluid flow, whether induced by a solute or water diuresis, is the primary mechanism of protection in acute urate nephropathy. At most, urine alkalinization plays a minor preventive role.


Assuntos
Diabetes Insípido/fisiopatologia , Rim/efeitos dos fármacos , Ácido Oxônico/farmacologia , Triazinas/farmacologia , Ácido Úrico/farmacologia , Animais , Pressão Sanguínea , Diurese , Taxa de Filtração Glomerular , Concentração de Íons de Hidrogênio , Inulina/urina , Rim/irrigação sanguínea , Rim/fisiologia , Masculino , Concentração Osmolar , Ratos , Fluxo Sanguíneo Regional , Ácido Úrico/sangue , Ácido Úrico/urina , Ácido p-Aminoipúrico/urina
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