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2.
Clin Epigenetics ; 16(1): 49, 2024 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-38549146

RESUMO

Acute lymphoblastic leukemia (ALL) is the most prevalent cancer in children, and despite considerable progress in treatment outcomes, relapses still pose significant risks of mortality and long-term complications. To address this challenge, we employed a supervised machine learning technique, specifically random survival forests, to predict the risk of relapse and mortality using array-based DNA methylation data from a cohort of 763 pediatric ALL patients treated in Nordic countries. The relapse risk predictor (RRP) was constructed based on 16 CpG sites, demonstrating c-indexes of 0.667 and 0.677 in the training and test sets, respectively. The mortality risk predictor (MRP), comprising 53 CpG sites, exhibited c-indexes of 0.751 and 0.754 in the training and test sets, respectively. To validate the prognostic value of the predictors, we further analyzed two independent cohorts of Canadian (n = 42) and Nordic (n = 384) ALL patients. The external validation confirmed our findings, with the RRP achieving a c-index of 0.667 in the Canadian cohort, and the RRP and MRP achieving c-indexes of 0.529 and 0.621, respectively, in an independent Nordic cohort. The precision of the RRP and MRP models improved when incorporating traditional risk group data, underscoring the potential for synergistic integration of clinical prognostic factors. The MRP model also enabled the definition of a risk group with high rates of relapse and mortality. Our results demonstrate the potential of DNA methylation as a prognostic factor and a tool to refine risk stratification in pediatric ALL. This may lead to personalized treatment strategies based on epigenetic profiling.


Assuntos
Metilação de DNA , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Canadá , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Resultado do Tratamento , Prognóstico , Recidiva
3.
Br J Haematol ; 204(4): 1529-1535, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38411250

RESUMO

Chronic myelomonocytic leukaemia (CMML) is a rare haematological disorder characterized by monocytosis and dysplastic changes in myeloid cell lineages. Accurate risk stratification is essential for guiding treatment decisions and assessing prognosis. This study aimed to validate the Artificial Intelligence Prognostic Scoring System for Myelodysplastic Syndromes (AIPSS-MDS) in CMML and to assess its performance compared with traditional scores using data from a Spanish registry (n = 1343) and a Taiwanese hospital (n = 75). In the Spanish cohort, the AIPSS-MDS accurately predicted overall survival (OS) and leukaemia-free survival (LFS), outperforming the Revised-IPSS score. Similarly, in the Taiwanese cohort, the AIPSS-MDS demonstrated accurate predictions for OS and LFS, showing superiority over the IPSS score and performing better than the CPSS and molecular CPSS scores in differentiating patient outcomes. The consistent performance of the AIPSS-MDS across both cohorts highlights its generalizability. Its adoption as a valuable tool for personalized treatment decision-making in CMML enables clinicians to identify high-risk patients who may benefit from different therapeutic interventions. Future studies should explore the integration of genetic information into the AIPSS-MDS to further refine risk stratification in CMML and improve patient outcomes.


Assuntos
Leucemia Mielomonocítica Crônica , Leucemia , Síndromes Mielodisplásicas , Humanos , Leucemia Mielomonocítica Crônica/diagnóstico , Leucemia Mielomonocítica Crônica/genética , Leucemia Mielomonocítica Crônica/tratamento farmacológico , Prognóstico , Inteligência Artificial , Síndromes Mielodisplásicas/terapia , Síndromes Mielodisplásicas/tratamento farmacológico , Medição de Risco
4.
Dig Dis Sci ; 68(8): 3442-3450, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37213003

RESUMO

BACKGROUND: Simvastatin administration to decompensated cirrhosis patients improved Child-Pugh (CP) at the end of a safety trial (EST). AIM: To evaluate whether simvastatin reduces cirrhosis severity through a secondary analysis of the safety trial. METHODS: Thirty patients CP class (CPc) CPc A (n = 6), CPc B (n = 22), and CPc C (n = 2) received simvastatin for one year. PRIMARY ENDPOINT: cirrhosis severity. Secondary endpoints: health-related quality of life (HRQoL) and hospitalizations for cirrhosis complications. RESULTS: Cirrhosis severity decreased baseline versus EST only across CP score (7.3 ± 1.3 versus 6.7 ± 1.7, P = 0.041), and CPc: 12 patients lessened from CPc B to CPc A, and three patients increased from CPc A to CPc B (P = 0.029). Due to cirrhosis severity changes and differences in clinical outcomes, 15 patients completed the trial as CPc AEST and another 15 as CPc B/C. At baseline, CPc AEST showed greater albumin and high-density lipoprotein cholesterol concentrations than CPc B/C (P = 0.036 and P = 0.028, respectively). Comparing EST versus baseline, only in CPc AEST, there was a reduction in white-cell blood (P = 0.012), neutrophils (P = 0.029), monocytes (P = 0.035), and C-reactive protein (P = 0.046); an increase in albumin (P = 0.011); and a recovery in HRQoL (P < 0.030). Finally, admissions for cirrhosis complications decreased in CPc AEST versus CPc B/C (P = 0.017). CONCLUSIONS: Simvastatin would reduce cirrhosis severity only in CPc B at baseline in a suitable protein and lipid milieu, possibly due to its anti-inflammatory effects. Furthermore, only in CPc AEST would improve HRQoL and reduce admissions by cirrhosis complications. However, as these outcomes were not primary endpoints, they require validation.


Assuntos
Qualidade de Vida , Sinvastatina , Humanos , Albuminas , Inflamação/tratamento farmacológico , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Cirrose Hepática/tratamento farmacológico , Sinvastatina/uso terapêutico
5.
Stud Health Technol Inform ; 290: 1018-1019, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35673184

RESUMO

There is a need for coordinating and manage the information flow between clinical, nursing, ancillary, cleaning and administrative staff to optimize patient transfers during admission and discharge. TECIPOT project proposes the incorporation of new technologies associated with the optimization of emergency circuits to improve the efficiency in the management of patients in the center, as well as improve the perception of patients and professionals about the processes of transfers of emergency patients, observation and discharge from the Hospital. The project proposes a 24 month study to evaluate the impact on healthcare processes.


Assuntos
Hospitalização , Transferência de Pacientes , Serviço Hospitalar de Emergência , Hospitais , Humanos , Alta do Paciente
6.
J Clin Med ; 11(6)2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35329942

RESUMO

Currently, brachytherapy is the most commonly used therapeutic approach for uveal melanomas. Surgical resection by means of endoresection or exoresection is an alternative approach. The present report recounts our experience over 15 years in the treatment of uveal melanoma using a combined approach of resection surgery with brachytherapy. This is a single-center observational retrospective cohort study in which we describe clinical outcomes, complications and survival in 35 cases of melanoma of the iris or the ciliary body after a combination of surgery and brachytherapy or brachytherapy alone. Local treatment of the tumor was successful in all cases with surgery and brachytherapy. The most frequent complications were scleromalacia, bullous keratopathy, retinal toxicity, cataracts, hypotonia, and photophobia. There were three cases of recurrence, all of which were found in the group of patients who had received brachytherapy alone, and in one case we had to perform a secondary enucleation due to tumor growth after brachytherapy. At present, only one patient has died during follow-up due to liver metastases six years after the start of treatment. In carefully selected patients, this approach can be effective and safe, as long as a close follow-up is carried out after surgery.

7.
Dig Dis Sci ; 66(9): 3199-3208, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33033975

RESUMO

BACKGROUND: The high mortality rate of decompensated cirrhosis underlines the need for new treatments. Experimental models of cirrhosis and its reported relationship with atherosclerotic cardiovascular disease have provided data supporting the rational use of statins in these patients. However, little is known about the safety of statins in this setting. AIM: We evaluate the safety of chronic simvastatin treatment in patients with decompensated cirrhosis. METHODS: We conducted a prospective, open, uncontrolled, phase 2a trial in 30 patients with Child-Pugh class A (n = 6), B (n = 22), and C (n = 2) decompensated cirrhosis. The patients received standard treatment throughout the trial plus simvastatin 20 mg/day for 2 weeks and thereafter simvastatin 40 mg/day up to 1 year. RESULTS: Sixteen out of 30 patients (53.3%) showed adverse events, including gastrointestinal toxicity (36.7%), muscle injury (MI) (36.7%), and headache (13.3%). No liver injury was registered. Due to MI alone, simvastatin dosage was reduced in 23.4% of cases and transiently interrupted in 13.3%. Once these adverse events were overcome, simvastatin was resumed until the end of the trial. MI was associated with baseline MELD score > 12 (p = 0.035) and with baseline Child-Pugh class C. No MI was associated with final Child-Pugh score ≤ 6 (p = 0.030) or final Child-Pugh class A (p = 0.020). CONCLUSIONS: Chronic treatment with simvastatin 40 mg/day in patients with decompensated cirrhosis was associated with several adverse events, being MI the only clinically significant one, which appears to be related to the simvastatin dosage and the degree of cirrhosis severity. Noticeably, no liver injury was recorded.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Cirrose Hepática , Fígado/efeitos dos fármacos , Sinvastatina , Argentina/epidemiologia , Doenças Cardiovasculares/prevenção & controle , Progressão da Doença , Relação Dose-Resposta a Droga , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/diagnóstico , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Feminino , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/diagnóstico , Gastroenteropatias/epidemiologia , Cefaleia/induzido quimicamente , Cefaleia/diagnóstico , Cefaleia/epidemiologia , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Masculino , Pessoa de Meia-Idade , Mialgia/induzido quimicamente , Mialgia/diagnóstico , Mialgia/epidemiologia , Avaliação de Processos e Resultados em Cuidados de Saúde , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricos , Índice de Gravidade de Doença , Sinvastatina/administração & dosagem , Sinvastatina/efeitos adversos
8.
Dig Dis Sci ; 64(3): 718-728, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30511199

RESUMO

BACKGROUND: Biannual ultrasound (US) is recommended as the clinical screening tool for hepatocellular carcinoma (HCC). The effectiveness of surveillance according to the place where US is performed has not been previously reported. AIMS: To compare the effectiveness of US performed in the center responsible for follow-up as opposed to US proceeding from centers other than that of follow-up. METHODS: This is a multicenter cohort study from Argentina. The last US was categorized as done in the same center or done in a different center from the institution of the patient's follow-up. Surveillance failure was defined as HCC diagnosis not meeting Barcelona Clinic Liver Cancer (BCLC) stages 0-A or when no nodules were observed at HCC diagnosis. RESULTS: From 533 patients with HCC, 62.4% were under routine surveillance with a surveillance failure of 38.8%. After adjusting for a propensity score matching, BCLC stage and lead-time survival bias, surveillance was associated with a significant survival benefit [HR of 0.51 (CI 0.38; 0.69)]. Among patients under routine surveillance (n = 345), last US was performed in the same center in 51.6% and in a different center in 48.4%. Similar rates of surveillance failure were observed between US done in the same or in a different center (32% vs. 26.3%; P = 0.25). Survival was not significantly different between both surveillance modalities [HR 0.79 (CI 0.53; 1.20)]. CONCLUSIONS: Routine surveillance for HCC in the daily practice improved survival either when performed in the same center or in a different center from that of patient's follow-up.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Detecção Precoce de Câncer/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Ultrassonografia/métodos , Idoso , Argentina , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo
9.
Biotechnol Prog ; 35(2): e2761, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30507028

RESUMO

This study describes the application of the multivariate curve resolution (MCR) analysis technique for real-time analysis of culture fluorescence during recombinant Pichia pastoris cultivation in a bioreactor. Fluorescence spectra were acquired with an on-line dual excitation wavelength fluorometer and then used to develop a real time MCR-based bioprocess monitoring and diagnostics tool. Initial bioreactor experiments using two similar recombinant antibody secreting P. pastoris cell lines showed significant differences in protein production. To distinguish between the contributions of operating conditions and the specific cell line's genetic composition to the observed differences in protein production, the bioreactor experiments were repeated and accompanied by real time MCR analysis. The tests demonstrated high sensitivity of MCR-derived "pure concentration" profiles to growth as well as to initial conditions, thus enabling real-time cultivation process trend diagnostics and fault detection. © 2018 Her Majesty the Queen in Right of Canada © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 35: e2761, 2019.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células , Fluorescência , Pichia/citologia , Análise Multivariada , Fatores de Tempo
10.
Eur J Gastroenterol Hepatol ; 30(4): 376-383, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29509603

RESUMO

BACKGROUND AND AIM: Adherence to the Barcelona Clinic Liver Cancer (BCLC) staging algorithm for the treatment of hepatocellular carcinoma is challenging in the daily practice. We aimed to analyze adherence to BCLC along with its effect on patient survival. PATIENTS AND METHODS: A cohort study was conducted in 14 hospitals from Argentina including patients with newly diagnosed hepatocellular carcinoma (2009-2016). Adherence was considered when the first treatment was the one recommended by the BCLC. RESULTS: Overall, 708 patients were included. At diagnosis, BCLC stages were as follows: stage 0 4%, A 43%, B 22%, C 9% and D 22%. Overall, 53% of the patients were treated according to BCLC, 24% were undertreated, and 23% overtreated. Adherence to BCLC increased to 63% in subsequent treatments. Independent factors associated with adherence to BCLC were the presence of portal hypertension [odds ratio: 1.63; 95% confidence interval (CI): 1.11-2.39] and BCLC stage C (odds ratio: 0.32; 95% CI: 0.12-0.72). In a multivariable model adjusting for portal hypertension and BCLC stages, adherence to BCLC showed improved survival (hazard ratio: 0.67; 95% CI: 0.52-0.87). CONCLUSION: Adherence to BCLC represents a challenge in the daily practice, with almost half of the patients being treated accordingly, showing that the decision-making process should be tailored to each individual patient.


Assuntos
Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Idoso , Algoritmos , Argentina/epidemiologia , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Feminino , Fidelidade a Diretrizes/estatística & dados numéricos , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Guias de Prática Clínica como Assunto , Sensibilidade e Especificidade , Análise de Sobrevida
11.
Radiother Oncol ; 124(1): 124-129, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28645692

RESUMO

PURPOSE: To report the clinical implementation of a novel external beam radiotherapy technique for accelerated partial breast irradiation treatments based on combined electron and photon modulated beams radiotherapy (MERT+IMRT) with conventional MLC. MATERIALS AND METHODS: A group of patients was selected to test the viability of the technique. The prescribed dose was 38.5Gy, following a hypofractionated schema, and the structures were defined following the NSABP-B39/RTOG-0413 protocol. The plans were calculated with an in-house Monte Carlo based planning system to consider explicitly the particle interactions with the MLC. An ad-hoc breast phantom was designed for a specific QA protocol. A reduced SSD was used for electron beams. Toxicity and cosmetic effects were assessed at every follow-up visit. RESULTS: All the plans achieved the dosimetric objectives and fulfilled the specific quality assurance protocol. Treatment delivery did not entail additional drawbacks for the clinical routine. Moderate or severe grade of toxicity was not reported, and the cosmetic results were comparable to those obtained with other APBI techniques. CONCLUSIONS: Results showed that MERT+IMRT with the MLC is a feasible and secure technique, and easy to be extended to other centers with the implementation of the adequate software for planning.


Assuntos
Neoplasias da Mama/radioterapia , Elétrons/uso terapêutico , Fótons/uso terapêutico , Planejamento da Radioterapia Assistida por Computador/métodos , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Imagens de Fantasmas , Radiometria/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos
12.
Mar Pollut Bull ; 70(1-2): 296-302, 2013 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-23499535

RESUMO

We analyzed polychlorinated biphenyls (PCBs), dichlorodiphenyl dichloroethane and its metabolites, hexachlorocyclohexanes (HCHs), polycyclic aromatic hydrocarbons (PAHs), and hopanes, in plastic resin pellets collected from nine locations along the Portuguese coast. Concentrations of a sum of 13 PCBs were one order of magnitude higher in two major cities (Porto: 307 ng/g-pellet; Lisboa: 273 ng/g-pellet) than in the seven rural sites. Lower chlorinated congeners were more abundant in the rural sites than in the cities, suggesting atmospheric dispersion. At most of the locations, PAH concentrations (sum of 33 PAH species) were ∼100 to ∼300 ng/g-pellet; however, three orders of magnitude higher concentrations of PAHs, with a petrogenic signature, were detected at a small city (Sines). Hopanes were detected in the pellets at all locations. This study demonstrated that multiple sample locations, including locations in both urban and remote areas, are necessary for country-scale pellet watch.


Assuntos
Monitoramento Ambiental/métodos , Hexaclorocicloexano/análise , Plásticos/química , Bifenilos Policlorados/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Oceano Atlântico , Portugal , Água do Mar/química , Poluição Química da Água/estatística & dados numéricos
13.
Microb Cell Fact ; 9: 70, 2010 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-20846434

RESUMO

BACKGROUND: Methylotrophic (methanol-utilizing) bacteria offer great potential as cell factories in the production of numerous products from biomass-derived methanol. Bio-methanol is essentially a non-food substrate, an advantage over sugar-utilizing cell factories. Low-value products as well as fine chemicals and advanced materials are envisageable from methanol. For example, several methylotrophic bacteria, including Methylobacterium extorquens, can produce large quantities of the biodegradable polyester polyhydroxybutyric acid (PHB), the best known polyhydroxyalkanoate (PHA). With the purpose of producing second-generation PHAs with increased value, we have explored the feasibility of using M. extorquens for producing functionalized PHAs containing C-C double bonds, thus, making them amenable to future chemical/biochemical modifications for high value applications. RESULTS: Our proprietary M. extorquens ATCC 55366 was found unable to yield functionalized PHAs when fed methanol and selected unsaturated carboxylic acids as secondary substrates. However, cloning of either the phaC1 or the phaC2 gene from P. fluorescens GK13, using an inducible and regulated expression system based on cumate as inducer (the cumate switch), yielded recombinant M. extorquens strains capable of incorporating modest quantities of C-C double bonds into PHA, starting from either C6= and/or C8=. The two recombinant strains gave poor results with C11=. The strain containing the phaC2 gene was better at using C8= and at incorporating C-C double bonds into PHA. Solvent fractioning indicated that the produced polymers were PHA blends that consequently originated from independent actions of the native and the recombinant PHA synthases. CONCLUSIONS: This work constitutes an example of metabolic engineering applied to the construction of a methanol-utilizing bacterium capable of producing functionalized PHAs containing C-C double bonds. In this regard, the PhaC2 synthase appeared superior to the PhaC1 synthase at utilizing C8= as source of C-C double bonds and at incorporating C-C double bonds into PHA from either C6= or C8=. The M. ex-phaC2 strain is, therefore, a promising biocatalyst for generating advanced (functionalized) PHAs for future high value applications in various fields.


Assuntos
Methylobacterium extorquens/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Aciltransferases/genética , Aciltransferases/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Metanol/metabolismo , Methylobacterium extorquens/genética , Methylobacterium extorquens/crescimento & desenvolvimento , Poli-Hidroxialcanoatos/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
14.
FEMS Microbiol Ecol ; 74(1): 136-45, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20662926

RESUMO

Besides its influence on plant growth and health, plant-associated bacteria exert an impact on fruit quality. Methylotrophic bacteria can enhance the biosynthesis of strawberry flavor compounds, especially the two furanoid compounds 2,5-dimethyl-4-hydroxy-2H-furanone (DMHF) and 2,5-dimethyl-4-methoxy-2H-furanone in vitro. Here, we report the selection and characterization of Methylobacterium extorquens DSM 21961, a strain that was able to enhance the furanone content ad planta under greenhouse conditions. For monitoring the colonization of strawberry plants, a strain-specific quantification system for M. extorquens DSM 21961 was developed. Specificity, linear range and quantitative limit of the system were shown, and successful application was demonstrated in a monitoring experiment of M. extorquens DSM 21961 on strawberry leaves under greenhouse conditions. Furthermore, the quantification of DMHF in strawberry fruits via GC indicated an increased biosynthesis of this compound in strawberry plants. The colonization behavior analyzed by confocal laser scanning microscopy using GFP-tagged cells revealed high colonization of the upper and the lower leaf surfaces, with a specific accumulation of bacterial cells on trichomes. The results support a biotechnological application of this promising flavor-stimulating agent.


Assuntos
4-Butirolactona/análogos & derivados , Fragaria/metabolismo , Furanos/metabolismo , Methylobacterium extorquens/crescimento & desenvolvimento , 4-Butirolactona/metabolismo , Cromatografia Gasosa , DNA Bacteriano/isolamento & purificação , Fragaria/microbiologia , Limite de Detecção , Methylobacterium extorquens/isolamento & purificação , Microscopia Confocal , Folhas de Planta/microbiologia , Reação em Cadeia da Polimerase
15.
Appl Environ Microbiol ; 76(15): 5058-66, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20562288

RESUMO

A novel tightly regulated gene expression system was developed for Escherichia coli by applying the regulatory elements of the Pseudomonas putida F1 cym and cmt operons to control target gene expression at the transcriptional level by using p-isopropylbenzoate (cumate) as an inducer. This novel expression system, referred to as the cumate gene switch, includes a specific expression vector, pNEW, that contains a partial T5 phage promoter combined with the Pseudomonas-based synthetic operator and the cymR repressor protein-encoding gene designed to express constitutively in the host strain. The induction of transcription relies on the addition of the exogenous inducer (cumate), which is nontoxic to the culture, water soluble, and inexpensive. The characteristics and potential of the expression system were determined. Using flow cytometry and fed-batch fermentations, we have shown that, with the newly developed cumate-regulated system, (i) higher recombinant product yields can be obtained than with the pET (isopropyl-beta-D-thiogalactopyranoside [IPTG])-induced expression system, (ii) expression is tightly regulated, (iii) addition of cumate quickly results in a fully induced and homogenous protein-expressing population in contrast to the bimodal expression profile of an IPTG-induced population, (iv) expression can be modulated by varying the cumate concentration, and (v) the cumate-induced population remains induced and fully expressing even at 8 h following induction, resulting in high yields of the target protein Furthermore, the cumate gene switch described in this article is applicable to a wide range of E. coli strains.


Assuntos
Clonagem Molecular/métodos , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Expressão Gênica , Engenharia Genética/métodos , Proteínas Recombinantes/biossíntese , Benzoatos/metabolismo , Vetores Genéticos , Pseudomonas , Pseudomonas putida/genética , Proteínas Recombinantes/genética , Ativação Transcricional
16.
Ann Hepatol ; 9(1): 63-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20332549

RESUMO

BACKGROUND/AIMS: No prospective study has been published investigating etiology of HCC in Latin America. The primary aim of this prospective study was to analyze the etiology of liver disease in patients with HCC from our area. Secondary aims were to evaluate staging using Okuda and BCLC classifications; and percentage of patients receiving treatment. METHODS: The Governing Board of the Latin American Association for the Study of the Liver designed the protocol. During a 18 month period, all members were invited to load their incident HCC cases on line. RESULTS: 240 cases from 9 countries were uploaded, 174 were male (72.5%), median age was 64 years, interquartile range 57-72. In 85.4% of cases, patients had underlying cirrhosis. Main etiological factors were: HCV in 74 patients (30.8%), alcohol in 49 (20.4%), cryptogenic cirrhosis in 35 (14.6%), HBV in 26 (10.8%), HCV plus alcohol in 14 (5.8%). Considering the combinations, hepatitis C was shown in 91 patients (38%); chronic alcoholism in 68 patients (28%); and hepatitis B in 33 patients (14%). There were no significant differences between the groups in the age at diagnosis. Percentage of male gender was higher in groups of alcohol (94%), HCV plus alcohol (93%) and HBV (85%) than in cryptogenic cirrhosis (60%) and HCV (59%) (p<0.001). CONCLUSIONS: Our prospective study showed that hepatitis C is the more frequent etiology of HCC in Latin America, followed by alcoholic cirrhosis. Demographical results showed a male predominance (male:female ratio 2.6) with an important proportion of patients being diagnosed at their sixties.


Assuntos
Carcinoma Hepatocelular/etiologia , Cooperação Internacional , Neoplasias Hepáticas/etiologia , Idoso , Carcinoma Hepatocelular/epidemiologia , Doença Crônica , Feminino , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite C/complicações , Hepatite C/epidemiologia , Humanos , Incidência , América Latina/epidemiologia , Cirrose Hepática Alcoólica/complicações , Cirrose Hepática Alcoólica/epidemiologia , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Retrospectivos
17.
Can J Microbiol ; 55(9): 1103-12, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19898553

RESUMO

We examined the methanotrophs in the Trail Road Landfill soils, Ottawa, Ontario, through cultivation-independent molecular assay and the culturing approach. Denaturing gradient gel electrophoresis (DGGE) analysis of amplified methanotroph-specific 16S rDNA gene fragments revealed a more diverse type I (RuMP pathway) methanotrophic community than type II (serine pathway) in 17 soil samples taken along a 50 m transect. The type II methanotrophic community was less diverse, with the dominance of Methylocystis in almost all samples, and clustering with high similarity (85%-88%). Also, the results showed that the C/N ratio of soil organic matter could significantly affect the methanotrophic community structures. The DGGE results were supported by sequence analysis of cloned pmoA. Members of the genera Methylobacter (type I), Methylocaldum (type X), and Methylocystis (type II) appeared to be the dominant methanotrophs. From methanotrophic enrichments, we isolated type I Methylobacter sp., and 3 type II Methylocystis spp.,which appeared to be one of the dominant bacteria species in the soil sample from which isolates were obtained.


Assuntos
Biodiversidade , Metagenoma , Metano/metabolismo , Microbiologia do Solo , Proteínas de Bactérias/genética , Carbono/análise , Análise por Conglomerados , Impressões Digitais de DNA , Eletroforese em Gel de Poliacrilamida , Dados de Sequência Molecular , Nitrogênio/análise , Desnaturação de Ácido Nucleico , Ontário , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Homologia de Sequência , Solo/análise
18.
Mar Pollut Bull ; 58(10): 1437-46, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19635625

RESUMO

Samples of polyethylene pellets were collected at 30 beaches from 17 countries and analyzed for organochlorine compounds. PCB concentrations in the pellets were highest on US coasts, followed by western Europe and Japan, and were lower in tropical Asia, southern Africa and Australia. This spatial pattern reflected regional differences in the usage of PCBs and was positively correlated with data from Mussel Watch, another monitoring approach. DDTs showed high concentrations on the US west coast and in Vietnam. In Vietnam, DDT was predominant over its metabolites (DDE and DDD), suggesting the principal source may be current usage of the pesticide for malaria control. High concentrations of pesticide HCHs were detected in the pellets from southern Africa, suggesting current usage of the pesticides in southern Africa. This study demonstrates the utility and feasibility of the International Pellet Watch approach to monitor POPs at a global scale.


Assuntos
DDT/análise , Monitoramento Ambiental/estatística & dados numéricos , Poluentes Ambientais/análise , Hidrocarbonetos Halogenados/análise , Bifenilos Policlorados/análise , Polietileno/química , Praias/estatística & dados numéricos , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Geografia
19.
Acta Gastroenterol Latinoam ; 39(1): 47-52, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19408739

RESUMO

Incidence and etiology of hepatocellular carcinoma (HCC) are variable around the world, depending mainly on theprevalence ofchronic hepatitis B carriers in each region. No study has been published analyzing epidemiological features of patients with HCC in Argentina. The aim of this retrospective study was to describe demographical and etiological results in a series of 587 consecutive patients with HCC diagnosed in 15 Hepatology and Gastroenterology Units distributed all around our country. Seventy-two per cent of patients were male, the median age was 62 years (interquartile range 55-68 years), and 93% had cirrhosis. Regarding to etiological data (fully available in 551 cases), main etiologies were chronic alcoholism in 229 patients (41.6%) (the sole risk factor in 182, associated to HCVin 35 and to HBV in 12); hepatitis C in 223 patients (40.5%) (the sole risk factor in 181, associated to alcoholism in 35 and to HBV in 7); hepatitis B in 74 patients (13.4%) (the sole risk factor in 55, associated to alcoholism in 12 and to HCV in 7); cryptogenic cirrhosis in 51 patients (9.2%). There were significant differences in percentages of genders between main groups: males were highly predominant in alcoholic cirrhosis (93%), hepatitis B (87%) and HCV plus alcohol (94%), compared to 63% in cryp togenic cirrhosis and 49% in hepatitis C (p<0.01). There were no differences in age at presentation between the main etiologies. In conclusion, the main causes of HCC in Argentina are alcoholic cirrhosis and hepatitis C (76% of cases). A majority of patients with HCC in our country are cirrhotics, males, and in their 6th or -7th decades of life.


Assuntos
Alcoolismo/complicações , Carcinoma Hepatocelular/etiologia , Hepatite B/complicações , Hepatite C/complicações , Neoplasias Hepáticas/etiologia , Adolescente , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Alcoolismo/epidemiologia , Argentina/epidemiologia , Carcinoma Hepatocelular/epidemiologia , Portador Sadio , Distribuição de Qui-Quadrado , Feminino , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Humanos , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
20.
Liver Int ; 29(3): 415-9, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18803587

RESUMO

BACKGROUND: Patients with spontaneous bacterial peritonitis (SBP) are at a high risk for renal failure and death despite successful treatment of infection. Intravenous (IV) albumin administration combined with antibiotic treatment has been shown to significantly decrease these risks. Clinical evidence is lacking on which patients are appropriate candidates for albumin treatment. AIM: To retrospectively analyse the usefulness of serum creatinine and bilirubin levels in predicting renal failure and mortality of patients hospitalized for SBP. METHODS: Between March 1995 and September 1998, 127 cirrhotic patients with SBP who had not received plasma expansion were evaluated. Eighty-one patients (64%) were classified as having a high risk for renal failure and mortality (serum bilirubin >4 mg/dl or serum creatinine >1 mg/dl) and 46 (36%) as having a low risk. RESULTS: At admission, 36.3% of all patients presented renal failure. Mortality during their hospitalization was 23% among those with a high risk and 6.5% among those with a low risk (P=0.01). Renal failure occurred in 23% of the high-risk patients, compared with 2.6% of the low-risk patients (P=0.006). The presence of hyponatraemia was significantly associated with higher mortality and renal failure in the high-risk group. CONCLUSIONS: Our retrospective review of patients with SBP suggests that serum bilirubin levels >4 mg and serum creatinine levels >1 mg/dl at the time of diagnosis represent significant risk factors for the clinical outcomes of patients with SBP. Patients without these risk factors may have a very low likelihood of death or renal failure.


Assuntos
Bilirrubina/sangue , Creatinina/sangue , Cirrose Hepática/complicações , Peritonite/complicações , Insuficiência Renal/metabolismo , Insuficiência Renal/mortalidade , Adulto , Idoso , Argentina , Humanos , Hiponatremia/etiologia , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Prognóstico , Insuficiência Renal/etiologia , Estudos Retrospectivos , Fatores de Risco
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