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1.
Rev. bras. cir. cardiovasc ; 37(5): 622-627, Sept.-Oct. 2022. tab
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1407282

RESUMO

ABSTRACT Introduction: Although endovascular correction is a promising perspective, the gold-standard treatment for thoracoabdominal aortic aneurisms and type-B dissections with visceral involvement remains open surgery, particularly due to its well-established long-term durability. This study aims to describe and evaluate public data from patients treated for thoracoabdominal aortic aneurism in the Brazilian public health system in a 12-year interval. Methods: Data from procedures performed between 2008 and 2019 were extracted from the national public database (Departamento de Informática do Sistema Único de Saúde, or DATASUS) using web scraping techniques. Procedures were evaluated regarding the yearly frequency of elective or urgency surgeries, in-hospital mortality, and governmental costs. All tests were done with a level of significance P<0.05. Results: A total of 812 procedures were analyzed. Of all surgeries, 67.98% were elective cases. There were 328 in-hospital deaths (mortality of 40.39%). In-hospital mortality was lower in elective procedures (26.92%) than in urgency procedures (46.74%) (P=0.008). Total governmental expenditure was $3.127.051,56 — an average of $3.774,22 for elective surgery and $3.791,93 for emergency surgery (P=0.999). Conclusion: The proportion of urgency procedures is higher than that recommended by international literature. Mortality was higher for urgent admissions, although governmental costs were equal for elective and urgent procedures; specialized referral centers should be considered by health policy makers.

2.
J Public Health Manag Pract ; 28(5 Suppl 5): S212-S222, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35867491

RESUMO

CONTEXT: Community health workers (CHWs) are vital frontline public health workers. Given their trusted roles and connection to and understanding of the communities they serve, CHWs are able to link underserved communities to resources and public health agencies. With CHWs' increased prominence in the public health workforce, calls have been made for expanding and supporting CHW training and career development opportunities. PROGRAM: Public health training centers (PHTCs) are mandated to assess public health workforce needs, provide evidence-based professional development trainings, and increase students' aptitude for working with underserved and underresourced communities through applied practice experiences. Public health training centers can support CHWs in each of these areas. DESIGN: Case studies from 3 PHTCs are provided to exemplify how PHTCs are well positioned to support the critical CHW workforce via assessment, training, and student field placements. IMPLEMENTATION: A regional needs assessment survey with a designated section for CHWs, the provision of accessible and relevant CHW training, and CHW-focused student field placements were implemented in PHTC Regions 6/South Central, 1/New England, and 5/Great Lakes, respectively. EVALUATION: The Region 6 needs assessment found that CHWs in Oklahoma had multiple core roles and training interests. A crosswalk of needs and available training in the region guided the creation of tailored CHW trainings. Across 35 CHW-targeted trainings in Region 1, 88.5% of trainees were satisfied with the trainings and identified actions they could take to apply information they learned to their work. Significant improvements ( P < .001) in knowledge occurred across the 13 trainings that had pre-/posttests. In Region 5, students engaged with CHW-based organizations in Wisconsin to inform statewide CHW priority action items and deliverables and found the field placements meaningful for their academic experience. DISCUSSION: Public health training centers' strengths in workforce development can complement and extend existing efforts to support the CHW workforce.


Assuntos
Agentes Comunitários de Saúde , Saúde Pública , Agentes Comunitários de Saúde/educação , Humanos , Avaliação das Necessidades , Saúde Pública/educação , Desenvolvimento de Pessoal , Estudantes
3.
Braz J Cardiovasc Surg ; 37(5): 622-627, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-35657309

RESUMO

INTRODUCTION: Although endovascular correction is a promising perspective, the gold-standard treatment for thoracoabdominal aortic aneurisms and type-B dissections with visceral involvement remains open surgery, particularly due to its well-established long-term durability. This study aims to describe and evaluate public data from patients treated for thoracoabdominal aortic aneurism in the Brazilian public health system in a 12-year interval. METHODS: Data from procedures performed between 2008 and 2019 were extracted from the national public database (Departamento de Informática do Sistema Único de Saúde, or DATASUS) using web scraping techniques. Procedures were evaluated regarding the yearly frequency of elective or urgency surgeries, in-hospital mortality, and governmental costs. All tests were done with a level of significance P<0.05. RESULTS: A total of 812 procedures were analyzed. Of all surgeries, 67.98% were elective cases. There were 328 in-hospital deaths (mortality of 40.39%). In-hospital mortality was lower in elective procedures (26.92%) than in urgency procedures (46.74%) (P=0.008). Total governmental expenditure was $3.127.051,56 - an average of $3.774,22 for elective surgery and $3.791,93 for emergency surgery (P=0.999). CONCLUSION: The proportion of urgency procedures is higher than that recommended by international literature. Mortality was higher for urgent admissions, although governmental costs were equal for elective and urgent procedures; specialized referral centers should be considered by health policy makers.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Procedimentos Endovasculares , Humanos , Aneurisma da Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/etiologia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/métodos , Saúde Pública , Brasil/epidemiologia , Procedimentos Endovasculares/métodos , Resultado do Tratamento , Estudos Retrospectivos , Complicações Pós-Operatórias/etiologia
4.
Einstein (Sao Paulo) ; 20: eAO6724, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35352768

RESUMO

OBJECTIVE: Despite the development of endovascular procedures, open repair remains the gold standard for the treatment of aortic thoracoabdominal aneurysms and some type B dissections, with well-established good outcomes and long-term durability at high-volume centers. The present study described and analyzed public data from patients treated in the public system in a 12-year interval, in a city where more than 5 million inhabitants depend on the Public Health System. METHODS: Public data from procedures performed between 2008 and 2019 were extracted using web scraping techniques. The variables available in the database include sex, age, elective or emergency hospital admission, number of surgeries, in-hospital mortality, length of stay, and information on reimbursement values. RESULTS: A total of 556 procedures were analyzed. Of these, 60.79% patients were men, and 41.18% were 65 years of age or older. Approximately 60% had a residential address registered in the municipality. Of all surgeries, 65.83% were elective cases. There were 178 in-hospital deaths (mortality of 32%). In the elective context, there were 98 deaths 26.78% versus 80 deaths (42.10%) in the emergency context (p=0.174). Mortality was lower in the hospitals that performed more surgeries. A total of USD 3,038,753.92 was paid, an average of USD 5,406.95 for elective surgery and USD 5,074.76 for emergency surgery (p=0.536). CONCLUSION: Mortality was no different between groups, and hospitals with higher volume presented more favorable outcomes. Specialized referral centers should be considered by health policy makers.


Assuntos
Aneurisma da Aorta Abdominal , Aneurisma da Aorta Torácica , Aneurisma da Aorta Abdominal/cirurgia , Aneurisma da Aorta Torácica/epidemiologia , Aneurisma da Aorta Torácica/cirurgia , Brasil/epidemiologia , Humanos , Tempo de Internação , Masculino , Saúde Pública
5.
Einstein (Säo Paulo) ; 20: eAO6724, 2022. tab
Artigo em Inglês | LILACS | ID: biblio-1364793

RESUMO

ABSTRACT Objective Despite the development of endovascular procedures, open repair remains the gold standard for the treatment of aortic thoracoabdominal aneurysms and some type B dissections, with well-established good outcomes and long-term durability at high-volume centers. The present study described and analyzed public data from patients treated in the public system in a 12-year interval, in a city where more than 5 million inhabitants depend on the Public Health System. Methods Public data from procedures performed between 2008 and 2019 were extracted using web scraping techniques. The variables available in the database include sex, age, elective or emergency hospital admission, number of surgeries, in-hospital mortality, length of stay, and information on reimbursement values. Results A total of 556 procedures were analyzed. Of these, 60.79% patients were men, and 41.18% were 65 years of age or older. Approximately 60% had a residential address registered in the municipality. Of all surgeries, 65.83% were elective cases. There were 178 in-hospital deaths (mortality of 32%). In the elective context, there were 98 deaths 26.78% versus 80 deaths (42.10%) in the emergency context (p=0.174). Mortality was lower in the hospitals that performed more surgeries. A total of USD 3,038,753.92 was paid, an average of USD 5,406.95 for elective surgery and USD 5,074.76 for emergency surgery (p=0.536). Conclusion Mortality was no different between groups, and hospitals with higher volume presented more favorable outcomes. Specialized referral centers should be considered by health policy makers.


Assuntos
Humanos , Masculino , Aneurisma da Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/epidemiologia , Aneurisma da Aorta Abdominal/cirurgia , Brasil/epidemiologia , Saúde Pública , Tempo de Internação
6.
J Environ Manage ; 285: 112134, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33588162

RESUMO

Pollution due to waste generated by the oil industry has led to serious damage to ecosystems and the environment. Therefore, preventive and corrective actions must be taken to mitigate the ecological impact of waste resulting from oil-related activities, to explore and implement environment-friendly approaches, and achieve sustainable development. In this study, an alternative treatment for cuttings generated during the drilling of oil wells was investigated by extracting the hydrocarbons present in such cuttings through the use of carbon dioxide under supercritical conditions. The extractions were performed in a Supercritical Fluid Technologies Inc. Model SFT-150 extractor, under varying pressure (2300-6600 psi) and temperature (52-109 °C), while maintaining constant carbon dioxide flow rate and extraction time, to analyse the effect of these two thermodynamic variables on the extraction efficiency. During supercritical extraction, 21.51 g of total hydrocarbons from drill cuttings (oil/kg) were recovered at 6000 psi and 100 °C. The results indicated that pressure had the strongest effect on the extraction yield, with only a small amount of hydrocarbons recovered at the lowest pressure for all fractions. At <3000 psi pressure, increasing the temperature led to a decrease in the amount of recovered hydrocarbons; at >3000 psi pressure, increasing the temperature led to an increase in the extraction yield.


Assuntos
Dióxido de Carbono , Ecossistema , Hidrocarbonetos , Campos de Petróleo e Gás , Temperatura
7.
Eur J Cardiothorac Surg ; 59(1): 276-277, 2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-32840317

RESUMO

Superior vena cava aneurysms are rare mediastinal vascular lesions. Aneurysms are classified as fusiform and saccular, with the latter being rarer than the former. We report the case of an asymptomatic 75-year-old woman who presented with a superior mediastinal mass. She underwent chest computed tomography angiography, which demonstrated a saccular aneurysm in the superior vena cava.


Assuntos
Aneurisma , Doenças do Mediastino , Idoso , Aneurisma/diagnóstico por imagem , Aneurisma/cirurgia , Feminino , Humanos , Mediastino/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Veia Cava Superior/diagnóstico por imagem
8.
Ann Vasc Surg ; 72: 666.e23-666.e32, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33333194

RESUMO

Saccular superior vena cava aneurysms (SVCAs) are one of the rarest causes of mediastinal masses. Seventy years after the first published case report, to the best of our knowledge, fewer than 30 cases have been described in the literature. This article provides an overview of the peculiarities regarding diagnosis and treatment performed in these cases and addresses the protocol adopted in our case report. We present a saccular aneurysm resected through median sternotomy, under cardiopulmonary bypass and superior vena cava reconstruction using a bovine pericardial patch.


Assuntos
Aneurisma/cirurgia , Pericárdio/transplante , Procedimentos de Cirurgia Plástica , Procedimentos Cirúrgicos Vasculares , Veia Cava Superior/cirurgia , Adolescente , Adulto , Idoso , Aneurisma/diagnóstico por imagem , Animais , Ponte Cardiopulmonar , Bovinos , Feminino , Xenoenxertos , Humanos , Masculino , Pessoa de Meia-Idade , Esternotomia , Resultado do Tratamento , Veia Cava Superior/diagnóstico por imagem , Adulto Jovem
9.
Chemosphere ; 259: 127418, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32574848

RESUMO

This work evaluated the effect of different initial biomass ratios in a co-culture of an alkaliphilic methanotrophic bacteria consortium (AMB) and the green microalga Scenedesmus obtusiusculus (GM) on the maximum CH4 specific biodegradation rate and global carbon uptake. The highest maximum specific biodegradation rate was 589 ± 0.01 mgCH4 gbiomass-1 d-1 obtained for a proportion of 3:1 AMB-GM (w w-1) and 8% of initial CH4 in the headspace. The methane degradation rate was 1.5 times lower than the value obtained solely by the AMB consortium, and it was associated with pH increases due to the evolved CO2 consumption by the microalga. Increased activity of the AMB consortium along the experiments was due to progressive adaptation. Massive sequencing revealed the presence of methanotrophic/methylotrophic species such as Methylocystis sp., Methylomicrobium sp., Methylophaga sp., and Hyphomicrobium sp. Successful complete methane and carbon dioxide uptake was obtained with the 3:1, 4:1, and 5:1 AMB-GM biomass ratios, while for the rest of the ratios tested, more than 70% of the initial methane was transformed into biomass and inorganic carbon. This study showed that methanotrophic-microalgal co-cultures lead to a promising strategy for greenhouse gases mitigation in one step.


Assuntos
Biodegradação Ambiental , Gases de Efeito Estufa , Metano/metabolismo , Microalgas/fisiologia , Biomassa , Dióxido de Carbono/metabolismo , Técnicas de Cocultura , Methylocystaceae , Microalgas/metabolismo , Scenedesmus/metabolismo
10.
Environ Sci Pollut Res Int ; 27(23): 28561-28574, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32130637

RESUMO

The microalga Scenedesmus obtusiusculus AT-UAM efficiently captured CO2 from two flue gas streams in a hybrid photobioreactor located in a greenhouse. Uptake rates of CO2, NO, and SO2 from a formulated gas stream were 160.7 mg L-1 day-1, 0.73 mg L-1 day-1, and 1.56 mg L-1 day-1, respectively, with removal efficiencies of 100% for all gases. Exhaust gases of a motor generator were also removed with uptake rates of 111.4 mg L-1 day-1, 0.42 mg L-1 day-1, and 0.98 mg L-1 day-1, obtaining removal efficiencies of 77%, 71%, and 53% for CO2, NOx, and SO2, respectively. On average, 61% of the CO2 from both flue gas streams was assimilated as microalgal biomass. The maximum CO2 uptake rate of 182 mg L-1 day-1 was achieved for formulated flue gas flow rate above 100 mL min-1. The biomass recovery of 88% was achieved using a 20-L electro-coagulation-flotation chamber coupled to a settler with a low specific power consumption of 0.27 kWh kg-1. The photobioreactor was operated for almost 7 months without contamination of invasive species or a decrease in the activity. It is a very encouraging result for long-term operation in flue gas treatment.


Assuntos
Microalgas , Scenedesmus , Biomassa , Dióxido de Carbono , Gases , Fotobiorreatores
11.
J Phycol ; 55(4): 898-911, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31012104

RESUMO

A population of Desertifilum (Cyanobacteria, Oscillatoriales) from an oligotrophic desertic biotope was isolated and characterized using a polyphasic approach including molecular, morphological, and ecological information. The population was initially assumed to be a new species based on ecological and biogeographic separation from other existing species, however, phylogenetic analyses based on sequences of the 16S rRNA gene and 16S-23S ITS region, placed this strain clearly within the type species, Desertifilum tharense. Comparative analysis of morphology, 16S rRNA gene similarity, 16S-23S ITS secondary structure, and percent dissimilarity of the ITS regions for all characterized strains supports placing the six Desertifilum strains (designated as PD2001/TDC17, UAM-C/S02, CHAB7200, NapGTcm17, IPPAS B-1220, and PMC 872.14) into D. tharense. The recognition of Desertifilum salkalinema and Desertifilum dzianense is not supported, although our analysis does support continued recognition of Desertifilum fontinale. Pragmatic criteria for recognition of closely related species are proposed based on this study and others, and more rigorous review of future taxonomic papers is recommended.


Assuntos
Cianobactérias , DNA Bacteriano , Filogenia , RNA Ribossômico 16S , Análise de Sequência de DNA
12.
Ann Vasc Surg ; 59: 1-4, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30802575

RESUMO

BACKGROUND: Duplex ultrasonography (DUS), although consolidated as the primary tool for the estimation of carotid stenosis, may be impaired by calcified plaques that promote acoustic shadow (AcS). AcS seems to hamper the quantification of the main parameter used in the determination of percentage stenosis, that is, the maximal peak systolic velocity (PSV) at the lesion site. The aim of our study was to compare the degrees of carotid artery stenosis in DUS/PSV and computed tomography angiography (CTA) in the presence of AcS. METHODS: During 36 months, 1,178 carotid DUS tests were performed. A total of 164 carotids in 139 patients showed AcS resulting from calcified plaques. Carotids with AcS were referred for a second imaging examination; thus, 62 carotids were analyzed by both DUS/PSV and CTA. CTA measured the area reduction at the lesion site to calculate the percent stenosis. PSV was measured immediately after the end of the AcS. According to velocities-based DUS criteria, stenoses were classified as mild (PSV < 125 cm/s), moderate (125 ≤ PSV ≤ 230 cm/s), and severe (PSV > 230). CTA and DUS/PSV measurements were compared to determine the accuracy of PSV in characterizing the severity of carotid stenosis with AcS. RESULTS: Of the 62 lesions, PSV characterized 10 as severe, 21 as moderate, and 31 as mild. According to the CTA study, there were 36 severe, 8 moderate, and 18 mild lesions. PSV underestimated in 27.79% the incidence of cases of severe carotid artery stenosis detected by the CTA. In addition, PSV overestimated the incidence of the cases of moderate and mild stenosis in 61.91% and 37.78%, respectively. The agreement ratio between the imaging examinations used in this study was 50%. DUS/PSV discretely correlated with CTA (r = 0.668, P < 0.0001, 95% confidence interval = 0.502-0.786). Using PSVs >125 and >230 as predictors of carotid lesions higher than 50% and 70%, respectively, the sensitivities were 63.3% and 27.8%, the specificities were 100%, the positive predictive values were 100%, and the negative predictive values were 71.9% and 50%. CONCLUSION: PSV alone is inadequate to quantify carotid stenosis in the presence of calcified plaques and AcS. Another image tool, such as CTA, could be recommendable for clinical decision-making.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Placa Aterosclerótica , Ultrassonografia Doppler Dupla , Calcificação Vascular/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Artérias Carótidas/patologia , Artérias Carótidas/fisiopatologia , Estenose das Carótidas/patologia , Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/terapia , Tomada de Decisão Clínica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Calcificação Vascular/patologia , Calcificação Vascular/fisiopatologia , Calcificação Vascular/terapia
13.
FEMS Microbiol Lett ; 365(3)2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29228188

RESUMO

Microalgae are among the most productive biological systems for converting sunlight into chemical energy, which is used to capture and transform inorganic carbon into biomass. The efficiency of carbon dioxide capture depends on the cultivation system configuration (photobioreactors or open systems) and can vary according to the state of the algal physiology, the chemical composition of the nutrient medium, and environmental factors such as irradiance, temperature and pH. This mini-review is focused on some of the most important environmental factors determining photosynthetic activity, carbon dioxide biofixation, cell growth rate and biomass productivity by microalgae. These include carbon dioxide and O2 concentrations, light intensity, cultivation temperature and nutrients. Finally, a review of the operation of microalgal cultivation systems outdoors is presented as an example of the impact of environmental conditions on biomass productivity and carbon dioxide fixation.


Assuntos
Reatores Biológicos , Dióxido de Carbono/metabolismo , Meio Ambiente , Microalgas/metabolismo , Concentração de Íons de Hidrogênio , Luz , Microalgas/crescimento & desenvolvimento , Microalgas/fisiologia , Nutrientes/metabolismo , Oxigênio/metabolismo , Fotossíntese , Temperatura
14.
Biotechnol Rep (Amst) ; 17: 16-23, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29276696

RESUMO

Scenedesmus obtusiusculus AT-UAM, isolated from Cuatro Ciénegas wetlands in Mexico was taxonomically, molecularly and biochemically compared to S. obtusiusculus CCAP 276/25 (Culture Collection of Algae and Protozoa, Scotland, UK). Analysis of Internal Transcribed Spacer 2 (ITS2) secondary structures confirmed that the mexican strain belongs to S. obtusiusculus with one change in the ITS2 nucleotide sequence. However, both strains exhibited different biochemical and fatty acid profiles and therefore biotechnological potential, emphasizing the need for deeper studies among strains of the same species. Furthermore, the biochemical variations of S. obtusiusculus AT-UAM under nitrogen starvation and different levels of irradiance were evaluated. The maximum lipid production (1730 mg L-1) was obtained at 613 µmol m-2 s-1 while the highest carbohydrate content (49%) was achieved at 896 µmol m-2 s-1. Additionally, this strain was capable of storing lipids (∼52%) and carbohydrates (∼40%) under outdoor condition depending on the light availability in the cultivation broth.

15.
Genome Announc ; 5(33)2017 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-28818899

RESUMO

Sphingobacterium sp. CZ-UAM was isolated from a methanotrophic consortium in mineral medium using methane as the only carbon source. A draft genome of 5.84 Mb with a 40.77% G+C content is reported here. This genome sequence will allow the investigation of potential methanotrophy in this isolated strain.

16.
Sci Total Environ ; 584-585: 1310-1316, 2017 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-28187940

RESUMO

The extensive microalgae diversity offers considerable versatility for a wide range of biotechnological applications in environmental and production processes. Microalgal cultivation is based on CO2 fixation via photosynthesis and, consequently, it is necessary to evaluate, in a short time and reliable way, the effect of the CO2 gas concentration on the consumption rate and establish the tolerance range of different strains and the amount of inorganic carbon that can be incorporated into biomass in order to establish the potential for industrial scale application. Dynamic experiments allow calculating the short-term microalgal photosynthetic activity of strains in photobioreactors. In this paper, the effect of step-changes in CO2 concentration fed to a 20L bubble column photobioreactor on the CO2 consumption rate of Scenedesmus obtusiusculus was evaluated at different operation times. The highest apparent CO2 consumption rate (336µmolm-2s-1 and 5.6% of CO2) was 6530mgCO2gb-1d-1 and it decreased to 222mgCO2gb-1d-1 when biomass concentration increased of 0.5 to 3.1gbL-1 and 5.6% of CO2 was fed. For low CO2 concentrations (<3.8%) the pH remained close to the optimal value (7.5 and 8). The CO2 consumption rates show that S. obtusiusculus was not limited by CO2 availability for concentrations above of 3.8%. The CO2 mass balance showed that 90% of the C-CO2 transferred was used for S. obtusiusculus growth.


Assuntos
Dióxido de Carbono/metabolismo , Fotobiorreatores , Scenedesmus/metabolismo , Biomassa , Microalgas/metabolismo
17.
Bioresour Technol ; 226: 238-246, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28011238

RESUMO

A Rhodobacter capsulatus strain and a photoheterotrophic culture (IZT) were cultivated to produce hydrogen under different light-dark cycles. A dark fermentation effluent (DFE) was used as substrate. It was found that IZT culture had an average cumulative hydrogen production (Paccum H2) of 1300±43mLH2L-1 under continuous illumination and light-dark cycles of 30 or 60min. In contrast, R. capsulatus reduced its Paccum H2 by 20% under 30:30min light-dark cycles, but tripled its poly-ß-hydroxybutyrate (PHB) content (308±2mgPHB gdw-1) compared to continuous illumination. The highest PHB content by IZT culture was 178±10mgPHB gdw-1 under 15:15min light-dark cycles. PCR-DGGE analysis revealed that the IZT culture was mainly composed of Rhodopseudomonas palustris identified with high nucleotide similarity (99%). The evaluated cultures might be used for hydrogen and PHB production. They might provide energy savings by using light-dark cycles and DFE valorization.


Assuntos
Hidroxibutiratos/química , Poliésteres/química , Rhodobacter capsulatus/metabolismo , Análise da Demanda Biológica de Oxigênio , DNA/química , Eletroforese em Gel de Gradiente Desnaturante , Fermentação , Hidrogênio/química , Cinética , Luz , Nucleotídeos/química , Fotoperíodo , Poliésteres/metabolismo , Rodopseudomonas/metabolismo
18.
Bioresour Technol ; 181: 128-35, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25647022

RESUMO

This paper evaluates the effect of the irradiance, pH and temperature on the photosynthetic activity (PA) of Scenedesmus obtusiusculus under N-replete and N-deplete conditions through oxygen measurements. The highest PA values were 160 mgO2 gb(-1) h(-1) at 620 µmol m(-2) s(-1), 35 °C and pH of 8 under N-replete conditions and 3.3 mgO2 gb(-1) h(-1) at 100 µmol m(-2) s(-1), 28.5 °C and pH of 5.5 for N-deplete conditions. Those operation conditions were tested in a flat-panel photobioreactor. The biomass productivity was 0.97 gb L(-1) d(-1) under N-replete conditions with a photosynthetic efficiency (PE) of 4.4% yielding 0.85 gb mol photon(-1). Similar biomass productivity was obtained under N-deplete condition; and the lipid productivity was 0.34 gL L(-1) d(-1) with a PE of 7.8% yielding 0.39 gL mol photon(-1). The apparent activation and deactivation energies were 16.1 and 30 kcal mol(-1), and 11.9 and 15.3 kcal mol(-1), for N-replete and N-deplete conditions, respectively.


Assuntos
Luz , Nitrogênio/farmacologia , Fotossíntese/efeitos dos fármacos , Fotossíntese/efeitos da radiação , Scenedesmus/fisiologia , Temperatura , Biomassa , Concentração de Íons de Hidrogênio , Lipídeos/biossíntese , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Oxigênio/metabolismo , Fotobiorreatores/microbiologia , Scenedesmus/efeitos dos fármacos , Scenedesmus/efeitos da radiação
19.
Biotechnol Lett ; 37(4): 807-14, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25432418

RESUMO

Pseudomonas citronellolis UAM-Ps1 co-metabolically transforms methyl tert-butyl ether (MTBE) to tert-butyl alcohol with n-pentane (2.6 mM), n-octane (1.5 mM) or dicyclopropylketone (DCPK) (4.4 mM), a gratuitous inducer of alkane hydroxylase (AlkB) activity. The reverse transcription quantitative real-time PCR was used to quantify the alkane monooxygenase (alkB) gene expression. The alkB gene was expressed in the presence of n-alkanes and DCPK and MTBE oxidation occurred only in cultures when alkB was transcribed. A correlation between the number of alkB transcripts and MTBE consumption was found (ΜΤΒΕ consumption in µmol = 1.44e(-13) x DNA copies, R(2) = 0.99) when MTBE (0.84 mM) was added. Furthermore, alkB was cloned and expressed into Escherichia coli and the recombinant AlkB had a molecular weight of 42 kDa. This is the first report where the expression of alkB is related to the co-metabolic oxidation of MTBE.


Assuntos
Éteres Metílicos/metabolismo , Oxigenases de Função Mista/metabolismo , Pseudomonas/metabolismo , terc-Butil Álcool/metabolismo , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Oxigenases de Função Mista/genética , Peso Molecular , Oxirredução , Pseudomonas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação
20.
Bioresour Technol ; 129: 686-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23298771

RESUMO

Methylobacterium organophilum CZ-2 synthesized polyhydroxyalkanoates (PHAs) under nitrogen limitation with CH4 as carbon source and when either citrate or propionate was added as cosubstrates. The highest PHAs content (yPHA) in closed flasks was obtained in the CH4-citrate and CH4-propionate experiments attaining values of 0.82 and 0.68, respectively. M. organophilum CZ-2 cultivated in bioreactors with citrate and continuous CH4 addition yielded a final PHAs concentration of 143 gm(-3) containing hydroxybutyrate (HB), hydroxyvalerate (HV) and hydroxyoctanoate (HO), in a 55:35:10 ratio, with, yPHA of 0.88 and a CH4 elimination capacity (EC) of 20 gm(-3) h(-1). With propionate, the yPHA was 0.3 and the EC around 8 gm(-3) h(-1). From 1H and 13C NMR experiments it was found that the polymer produced with CH4-citrate contained six different monomers: 3HB, 3HV, 4HV, 4-hydroxyheptanoate (4HH), 3HO and 4HO, showing the great versatility of this PHAs producing bacterium.


Assuntos
Ácido Cítrico/metabolismo , Metano/metabolismo , Methylobacterium/metabolismo , Poli-Hidroxialcanoatos/biossíntese , Poli-Hidroxialcanoatos/isolamento & purificação , Propionatos/metabolismo , Methylobacterium/classificação , Especificidade da Espécie
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