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1.
Rev Clin Esp ; 221(7): 400-403, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33288965

RESUMO

OBJECTIVE: To analyze the association between public health expenditure per capita and the mortality rate due to COVID-19 in Europe and Spain. MATERIAL AND METHODS: Pearson's correlation coefficient was used to compare and contrast the mortality rate due to COVID-19 between countries and autonomous communities with higher and lower public health expenditure per capita than the mean. RESULTS: No correlation between the public health expenditure per capita and the mortality rate due to COVID-19 (r: 0.3; p = 0.14) was found among European countries or Spain's Autonomous Communities (r: 0.03; p = 0.91). No significant differences were found when comparing the mortality rate due to COVID-19 among the public health expenditure per capita groups. CONCLUSIONS: The available evidence does not support association between «low¼ public healthcare expenditure and the poor outcomes observed in Spain during the COVID-19 pandemic. Increased funding for the Spanish National Health System should be earmarked for structural reforms to increase its social efficiency.

2.
Ann Hematol ; 99(7): 1627-1634, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32451707

RESUMO

There is no standard treatment for relapsed follicular lymphoma (FL). Although platinum-based combinations are one of the most used treatments, few data have been reported in this setting. Our aim was to analyse R-ESHAP efficacy in relapsed FL patients. We retrospectively analysed 80 FL patients treated with R-ESHAP in the first or successive relapses. Responding patients received a stem cell transplantation following R-ESHAP. Seventeen histologically transformed patients were included. Median age was 50 years. At R-ESHAP initiation, 85% of the patients were in an advanced stage, 28% had a bulky disease and 40% had increased LDH. There were no statistically significant differences between POD24 and non-POD24 patients in terms of response to R-ESHAP (ORR 72% vs. 93%, p = 0.109). When analyzing R-ESHAP efficacy according to the response to the immediately previous line, patients achieving CR or PR had better CR rates to R-ESHAP than those who did not respond (CR of 57% vs. 15%, respectively, p = 0.009), as well as differences in OS (7.2 vs. 1.4 years, p < 0.0001) and in PFS (2.1 vs. 0.3 years, p < 0.0001). R-ESHAP is an effective treatment in relapsed FL patients who respond to the previous line and has to be considered as an adequate alternative for some patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Linfoma Folicular/tratamento farmacológico , Linfoma Folicular/patologia , Rituximab/administração & dosagem , Terapia de Salvação/métodos , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Citarabina/administração & dosagem , Citarabina/efeitos adversos , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Linfoma Folicular/mortalidade , Masculino , Metilprednisolona/administração & dosagem , Metilprednisolona/efeitos adversos , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva , Estudos Retrospectivos , Rituximab/efeitos adversos , Espanha/epidemiologia , Análise de Sobrevida , Falha de Tratamento , Resultado do Tratamento , Adulto Jovem
3.
Eur J Cancer Care (Engl) ; 27(2): e12794, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29168594

RESUMO

Communication and the care of patients with advanced cancer are a dynamic, interactive and challenging process, often characterised in every day practice by discontinuity and lack of coordination. The objective of this study was to explore the patients' and family-caregivers' needs and preferences regarding communication, quality of life and care over the trajectory of disease. The second aim was to assess health professionals' views on a longitudinally structured, forward-thinking communication approach based on defined milestones. A qualitative approach was chosen incorporating semi-structured interviews with nine patients with metastatic lung cancer and nine relatives, and focus groups with 15 healthcare providers from different professions involved in the care of these patients. Patients and relatives described a situation of shock and coping deficits with moments of insufficient communication and lack of continuity in care. Healthcare providers reported the strong need for improvement in communication within the team and between patients and professionals and welcomed the implementation of a longitudinal communication approach. Requirements for the implementation of a longitudinal communication approach include specific communication training with focus on the process that patients and relatives are involved in. Team-building measures and the necessary flexibility to respect individuality in life should be incorporated.


Assuntos
Atitude do Pessoal de Saúde , Cuidadores/psicologia , Comunicação , Neoplasias Pulmonares/psicologia , Cuidados Paliativos/normas , Relações Profissional-Paciente , Assistência Terminal/normas , Adulto , Idoso , Continuidade da Assistência ao Paciente/normas , Feminino , Grupos Focais , Humanos , Comunicação Interdisciplinar , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Preferência do Paciente , Pesquisa Qualitativa , Qualidade de Vida
5.
Food Microbiol ; 57: 45-53, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27052701

RESUMO

Fresh fruit is highly perishable during postharvest life, mainly due to fungal growth. Thus, fungal control is an important goal for the fruit industry. In this work, a selection of antagonistic yeasts isolated from fig and breba crops were screened in vitro. The isolated yeasts were challenged with three moulds isolated from decayed figs and breba crops, identified as Penicillium expansum M639 and Cladosporium cladosporioides M310 and M624, and pathogenic moulds Botrytis cinerea CECT20518 and Monilia laxa CA1 from culture collections. Two yeast isolates, Hanseniaspora opuntiae L479 and Metschnikowia pulcherrima L672, were selected for their ability to inhibit the growth of aforementioned moulds. These yeasts reduced the radial growth of moulds on PDA by between 45.23% and 66.09%. Antagonistic activity was associated with the interaction of live yeast cells with moulds. M. pulcherrima L672 apparently parasitised C. cladosporioides isolates. In addition, challenges were assayed using wounded apples and nectarines, with significant reductions in percent infection and lesion size for all moulds tested. To our knowledge, this is the first report identifying H. opuntiae as an antagonist against different pathogenic moulds.


Assuntos
Antibiose , Ficus/microbiologia , Frutas/microbiologia , Malus/microbiologia , Doenças das Plantas/prevenção & controle , Leveduras/fisiologia , Botrytis/crescimento & desenvolvimento , Candida/crescimento & desenvolvimento , Penicillium/crescimento & desenvolvimento , Doenças das Plantas/microbiologia , Néctar de Plantas , Leveduras/genética , Leveduras/isolamento & purificação
6.
J Environ Manage ; 177: 65-73, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27082258

RESUMO

This work reports the removal of textile dyes and metallic ions by means of adsorption and coagulation-flocculation using two polyelectrolytes and two macroelectrolytes containing sulfonic acid groups. The adsorption of textile dyes was studied in aqueous solutions containing cationic dyes and in wastewater containing a vat dye. Also, removal of vat and naphthol dyes was studied using the process of coagulation-flocculation. The results show these materials possess elevated adsorption capacity, and they accomplished removal rates above 97% in aqueous solutions. The removal of the vat dye improved the quality of the wastewater notably, and an uncolored effluent was obtained at the end of the treatment. The treatment using adsorption decreased the values for coloration, conductivity, suspended solids, and pH. The removal of vat and naphthol dyes by means of coagulation-flocculation was studied as well, and removal rates of 90% were obtained. The polyelectrolytes and macroelectrolytes also proved effective in the adsorption of metallic ions in wastewater. The treatment using adsorption accomplished high removal rates of metallic ions, and it showed greater selectivity towards Cu(2+), Fe(3+) and Pb(2+). A decrease in the content of solids as well as the values for COD and conductivity was observed in the wastewater as well. The analyses of FT-IR indicated that cationic dyes and metallic ions were chemisorbed by means of ionic exchange.


Assuntos
Corantes/química , Polieletrólitos/química , Ácidos Sulfônicos/química , Indústria Têxtil , Águas Residuárias/química , Poluentes Químicos da Água/química , Adsorção , Corantes/análise , Floculação , Concentração de Íons de Hidrogênio , Troca Iônica , Espectroscopia de Infravermelho com Transformada de Fourier , Têxteis , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/análise
7.
J Econ Entomol ; 108(4): 2117-20, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26470359

RESUMO

Pheromone-lured funnel traps are widely used for pest monitoring and mass trapping in agricultural fields and stores. DDVP vapona (dichlorvos), the insecticide of choice as a killing agent inside traps, has been banned, and research on new products is being pursued. Essential oils (EO) could be an alternative if properly formulated. To test their potential, beads of encapsulated coriander and basil EO were tested in funnel traps in stores of almonds and pet foods during 2 mo. The number of adult moth (Plodia interpunctella (Hübner) and Ephestia kuehniella Zeller) dead captures was similar with either coriander or basil EO beads and with vapona tablets while there were more insects alive in the control. These preliminary results indicate a good potential for the development of such natural products as an alternative to synthetic insecticides to include them inside funnel traps.


Assuntos
Controle de Insetos/métodos , Inseticidas , Mariposas , Óleos Voláteis , Animais
8.
Eur J Dent Educ ; 19(4): 242-50, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25470689

RESUMO

INTRODUCTION: Accumulating evidence amongst dental students indicates an alarming prevalence of stress, which can precipitate the development of burnout--a state of mental or physical exhaustion and disengagement. Understanding individual and educational correlates of burnout is necessary for its prevention. The aims of this study were to determine the prevalence of burnout amongst a large sample of Colombian dental undergraduates and investigate its psychosocial and educational correlates. MATERIALS AND METHODS: Survey data collected from 5647 students participating in the Stress in Colombian Dental Education study were used for this analysis. Burnout was measured using the Maslach Burnout Inventory-Student Survey (MBI-SS). Covariates included participants' socio-demographic characteristics and perceived stress, as well as educational environment factors. Descriptive, bivariate and multivariate methods based on multilevel mixed-effects logistic regression modelling were used for data analysis. RESULTS: Seven per cent of the students surveyed met the criteria for burnout. The prevalence of burnout was higher amongst upper classes, older and married students, those who reported not having passed all required courses and not having dentistry as their first career choice, as well as students in public institutions and those with large class sizes. Moreover, students' perceived stress in the domains of workload and self-efficacy was significantly and positively associated with burnout. CONCLUSIONS: Both personal and educational environment characteristics were found to be associated with burnout. Irrespective of these factors, students' perceived stress with regard to workload and self-efficacy was a strong influence on burnout and its alleviation may be a promising avenue to prevent psychological morbidity.


Assuntos
Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Educação em Odontologia , Estudantes de Odontologia/psicologia , Adolescente , Adulto , Colômbia/epidemiologia , Avaliação Educacional , Feminino , Humanos , Masculino , Razão de Chances , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Estresse Psicológico , Inquéritos e Questionários , Carga de Trabalho , Adulto Jovem
9.
Bull Math Biol ; 76(2): 292-313, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24257901

RESUMO

Numerous therapies have been implemented in an effort to minimize the debilitating effects of the degenerative eye disease Retinitis Pigmentosa (RP), yet none have provided satisfactory long-term solution. To date there is no treatment that can halt the degeneration of photoreceptors. The recent discovery of the RdCVF protein has provided researchers with a potential therapy that could slow the secondary wave of cone death. In this work, we build on an existing mathematical model of photoreceptor interactions in the presence of RP and incorporate various treatment regiments via RdCVF. Our results show that an optimal control exists for the administration of RdCVF. In addition, our numerical solutions show the experimentally observed rescue effect that the RdCVF has on the cones.


Assuntos
Modelos Biológicos , Células Fotorreceptoras de Vertebrados/fisiologia , Retinose Pigmentar/terapia , Tiorredoxinas/fisiologia , Algoritmos , Morte Celular/fisiologia , Sobrevivência Celular/fisiologia , Progressão da Doença , Humanos , Conceitos Matemáticos , Mutação , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/patologia , Epitélio Pigmentado da Retina/patologia , Retinose Pigmentar/patologia , Retinose Pigmentar/fisiopatologia , Tiorredoxinas/administração & dosagem
10.
Indoor Air ; 23(4): 342-52, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23311877

RESUMO

Nearly half of the world's population depends on biomass fuels to meet domestic energy needs, producing high levels of pollutants responsible for substantial morbidity and mortality. We compare carbon monoxide (CO) and particulate matter (PM2.5) exposures and kitchen concentrations in households with study-promoted intervention (OPTIMA-improved stoves and control stoves) in San Marcos Province, Cajamarca Region, Peru. We determined 48-h indoor air concentration levels of CO and PM2.5 in 93 kitchen environments and personal exposure, after OPTIMA-improved stoves had been installed for an average of 7 months. PM2.5 and CO measurements did not differ significantly between OPTIMA-improved stoves and control stoves. Although not statistically significant, a post hoc stratification of OPTIMA-improved stoves by level of performance revealed mean PM2.5 and CO levels of fully functional OPTIMA-improved stoves were 28% lower (n = 20, PM2.5, 136 µg/m(3) 95% CI 54-217) and 45% lower (n = 25, CO, 3.2 ppm, 95% CI 1.5-4.9) in the kitchen environment compared with the control stoves (n = 34, PM2.5, 189 µg/m(3), 95% CI 116-261; n = 44, CO, 5.8 ppm, 95% CI 3.3-8.2). Likewise, although not statistically significant, personal exposures for OPTIMA-improved stoves were 43% and 17% lower for PM2.5 (n = 23) and CO (n = 25), respectively. Stove maintenance and functionality level are factors worthy of consideration for future evaluations of stove interventions.


Assuntos
Poluição do Ar em Ambientes Fechados/prevenção & controle , Culinária/instrumentação , Calefação/instrumentação , Fumaça/análise , Poluição do Ar em Ambientes Fechados/análise , Poluição do Ar em Ambientes Fechados/estatística & dados numéricos , Exposição Ambiental , Eucalyptus , Feminino , Humanos , Peru , População Rural , Madeira
11.
Mol Psychiatry ; 15(10): 1006-15, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19455147

RESUMO

Genetic studies of autism over the past decade suggest a complex landscape of multiple genes. In the face of this heterogeneity, studies that include large extended pedigrees may offer valuable insights, as the relatively few susceptibility genes within single large families may be more easily discerned. This genome-wide screen of 70 families includes 20 large extended pedigrees of 6-9 generations, 6 moderate-sized families of 4-5 generations and 44 smaller families of 2-3 generations. The Center for Inherited Disease Research (CIDR) provided genotyping using the Illumina Linkage Panel 12, a 6K single-nucleotide polymorphism (SNP) platform. Results from 192 subjects with an autism spectrum disorder (ASD) and 461 of their relatives revealed genome-wide significance on chromosome 15q, with three possibly distinct peaks: 15q13.1-q14 (heterogeneity LOD (HLOD)=4.09 at 29 459 872 bp); 15q14-q21.1 (HLOD=3.59 at 36 837 208 bp); and 15q21.1-q22.2 (HLOD=5.31 at 55 629 733 bp). Two of these peaks replicate earlier findings. There were additional suggestive results on chromosomes 2p25.3-p24.1 (HLOD=1.87), 7q31.31-q32.3 (HLOD=1.97) and 13q12.11-q12.3 (HLOD=1.93). Affected subjects in families supporting the linkage peaks found in this study did not reveal strong evidence for distinct phenotypic subgroups.


Assuntos
Transtorno Autístico/genética , Cromossomos Humanos Par 15 , Ligação Genética , Estudo de Associação Genômica Ampla , Adolescente , Criança , Feminino , Heterogeneidade Genética , Genótipo , Humanos , Escore Lod , Masculino , Linhagem , Fenótipo , Utah
12.
Rev Clin Esp (Barc) ; 221(7): 400-403, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34049840

RESUMO

OBJECTIVE: To analyze the association between public health expenditure per capita and the mortality rate due to COVID-19 in Europe and Spain. MATERIAL AND METHODS: Pearson's correlation coefficient was used to compare and contrast the mortality rate due to COVID-19 between countries and autonomous communities with higher and lower public health expenditure per capita than the mean. RESULTS: No correlation between the public health expenditure per capita and the mortality rate due to COVID-19 (r: 0.3; p = 0.14) was found among European countries or Spain's Autonomous Communities (r: 0.03; p = 0.91). No significant differences were found when comparing the mortality rate due to COVID-19 among the public health expenditure per capita groups. CONCLUSIONS: The available evidence does not support association between «low¼ public healthcare expenditure and the poor outcomes observed in Spain during the COVID-19 pandemic. Increased funding for the Spanish National Health System should be earmarked for structural reforms to increase its social efficiency.


Assuntos
COVID-19/mortalidade , Gastos em Saúde , Saúde Pública/economia , Europa (Continente)/epidemiologia , Humanos , Espanha/epidemiologia
14.
Math Med Biol ; 37(1): 1-21, 2020 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30810166

RESUMO

People afflicted with diseases such as retinitis pigmentosa and age-related macular degeneration experience a decline in vision due to photoreceptor degeneration, which is currently unstoppable and irreversible. Currently there is no cure for diseases linked to photoreceptor degeneration. Recent experimental work showed that mesencephalic astrocyte-derived neurotrophic factor (MANF) can reduce neuron death and, in particular, photoreceptor death by reducing the number of cells that undergo apoptosis. In this work, we build on an existing system of ordinary differential equations that represent photoreceptor interactions and incorporate MANF treatment for three experimental mouse models having undergone varying degrees of photoreceptor degeneration. Using MANF treatment levels as controls, we investigate optimal control results in the three mouse models. In addition, our numerical solutions match the experimentally observed surviving percentage of photoreceptors and our uncertainty and sensitivity analysis identifies significant parameters in the math model both with and without MANF treatment.


Assuntos
Fatores de Crescimento Neural/uso terapêutico , Células Fotorreceptoras de Vertebrados/efeitos dos fármacos , Células Fotorreceptoras de Vertebrados/patologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Simulação por Computador , Modelos Animais de Doenças , Humanos , Degeneração Macular/tratamento farmacológico , Degeneração Macular/patologia , Degeneração Macular/fisiopatologia , Conceitos Matemáticos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Modelos Neurológicos , Degeneração Neural/tratamento farmacológico , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Fatores de Crescimento Neural/fisiologia , Células Fotorreceptoras de Vertebrados/fisiologia , Células Fotorreceptoras Retinianas Cones/efeitos dos fármacos , Células Fotorreceptoras Retinianas Cones/patologia , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Fotorreceptoras Retinianas Bastonetes/efeitos dos fármacos , Células Fotorreceptoras Retinianas Bastonetes/patologia , Células Fotorreceptoras Retinianas Bastonetes/fisiologia , Retinose Pigmentar/tratamento farmacológico , Retinose Pigmentar/patologia , Retinose Pigmentar/fisiopatologia
15.
Phys Med ; 77: 194-203, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32882615

RESUMO

PURPOSE: To develop an on-lattice agent-based model describing the growth of multicellular tumor spheroids using simple Monte Carlo tools. METHODS: Cells are situated on the vertices of a cubic grid. Different cell states (proliferative, hypoxic or dead) and cell evolution rules, driven by 10 parameters, and the effects of the culture medium are included. About twenty spheroids of MCF-7 human breast cancer were cultivated and the experimental data were used for tuning the model parameters. RESULTS: Simulated spheroids showed adequate sizes of the necrotic nuclei and of the hypoxic and proliferative cell phases as a function of the growth time, mimicking the overall characteristics of the experimental spheroids. The relation between the radii of the necrotic nucleus and the whole spheroid obtained in the simulations was similar to the experimental one and the number of cells, as a function of the spheroid volume, was well reproduced. The statistical variability of the Monte Carlo model described the whole volume range observed for the experimental spheroids. Assuming that the model parameters vary within Gaussian distributions it was obtained a sample of spheroids that reproduced much better the experimental findings. CONCLUSIONS: The model developed allows describing the growth of in vitro multicellular spheroids and the experimental variability can be well reproduced. Its flexibility permits to vary both the agents involved and the rules that govern the spheroid growth. More general situations, such as, e. g., tumor vascularization, radiotherapy effects on solid tumors, or the validity of the tumor growth mathematical models can be studied.


Assuntos
Neoplasias da Mama , Esferoides Celulares , Feminino , Humanos , Cinética , Método de Monte Carlo , Necrose
16.
Sci Total Environ ; 407(8): 2836-44, 2009 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-19185330

RESUMO

An interdisciplinary investigation, involving environmental geochemists, epidemiologists, nurses, and anthropologists, was undertaken to determine the contamination source and pathway of an on-going outbreak of lead poisoning among migrants originating from Zimatlán, Oaxaca, Mexico and living in Seaside, California, and among their US-born children. An initial investigation in Seaside identified grasshopper foodstuff ("chapulines") imported from Mexico and consumed as snacks, as containing alarmingly high lead concentrations (up to 2300 mg/kg). The focus in the present work concentrates on the Oaxacan area of origin of the problem in Mexico, and two potential sources of contamination were investigated: wind-borne dusts from existing mine residues as potential contaminants of soil, plant, and fauna; and food preparation practices using lead-glazed ceramic cookware. Over a three year period, sampling was conducted in Oaxaca using community-level sampling and also targeted sampling with families of cases with lead poisoning in California. In addition to fresh field chapulines, we analyzed for total lead: soil, water, mine residues, and plant materials, both from areas adjacent to or at an abandoned waste site containing mine tailings, and from fields where chapulines are collected; foodstuffs gathered in community markets or in a food transport business; and foodstuffs and cookware gathered from relatives of case families in California. Also, selected new and used lead-glazed clay cookware was extracted for lead, using 0.02 M citric acid and with 4% acetic acid. The results indicated significant presence of lead in mine wastes, in specific foodstuffs, and in glazed cookware, but no extensive soil contamination was identified. In-situ experiments demonstrated that lead incorporation in food is made very efficient through grinding of spices in glazed cookware, with the combination of a harsh mechanical action and the frequent presence of acidic lime juice, but without heating, resulting in high but variable levels of contamination.


Assuntos
Cerâmica/química , Utensílios de Alimentação e Culinária , Monitoramento Ambiental , Contaminação de Alimentos/análise , Manipulação de Alimentos , Chumbo/análise , Humanos , Resíduos Industriais/análise , Chumbo/química , México , Mineração , Especiarias
17.
Bioresour Technol ; 280: 404-411, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30784990

RESUMO

The improvement of photosynthetic efficiency in a 100 m2 raceway reactor by enhancement of light regime to which the cells are exposed is here reported. From Computational Fluid Dynamics it was calculated that the light exposure times ranged from 0.4 to 3.6 s while the exposure times to darkness were much longer, from 6 to 21 s. It was demonstrated that these times are too long for light integration, the cells fully adapting to local irradiances. This phenomenon was validated in the real outdoor raceway at different seasons. Simulations allows to confirm that if total light integration is achieved biomass productivity can increase up to 40 g/m2·day compared to 29 g/m2·day obtained considering local adaptation, which is close to the experimental value of 25 g/m2·day. This paper provides clear evidence of microalgae cell adaptation to local irradiance because of the unfavourable cell movement pattern in raceway reactors.


Assuntos
Microalgas/metabolismo , Fotossíntese , Biomassa , Hidrodinâmica , Estações do Ano
18.
Open Life Sci ; 14: 165-178, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33817149

RESUMO

A random transposition mutant library of B. gladioli UAPS07070 was analyzed for searching mutants with impaired microbial antagonism. Three derivates showed diminished antimicrobial activity against a sensitive strain. The mutated loci showed high similarity to the quorum sensing genes of the AHL-synthase and its regulator. Another mutant was affected in a gene coding for a LysrR-type transcriptional regulator. The production of toxoflavin, the most well known antimicrobial-molecule and a major virulence factor of plant-pathogenic B. glumae and B. gladioli was explored. The absence of a yellowish pigment related to toxoflavin and the undetectable transcription of toxA in the mutants indicated the participation of the QS system and of the LysR-type transcriptional regulator in the regulation of toxoflavin. Additionally, those genes were found to be related to the swarming phenotype. Lettuce inoculated with the AHL synthase and the lysR mutants showed less severe symptoms. We present evidence of the participation of both, the quorum sensing and for the first time, of a LysR-type transcriptional regulator in antibiosis and swarming phenotype in a strain of B. gladioli.

19.
Arch Environ Contam Toxicol ; 55(4): 566-75, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18320262

RESUMO

The goal of this work was to identify the solid-phase control on lead (Pb) bioaccessibility in soils impacted by smelter activities in the city of San Luis Potosi, in north-central Mexico. Total Pb concentrations in 30 ha of soil terrain from a residential area adjacent to the smelter showed levels above the 400-mg/kg intervention guideline dictated by Mexican Environmental regulations. These concentrations, although raising human health and environmental concerns, showed low water-soluble lead (<0.1 mg/L) and relatively low lead bioaccessibility (2.4-20.5%). X-ray diffraction and electron microscopy techniques showed, in addition to common Pb phases reported in similar contaminated environments [galena (PbS) and anglesite (PbSO(4))], the presence of a solid lead arsenate phase. The Pb solubility measured in soils agrees very well with the low solubility reported for the Pb minerals identified and explains the relatively low Pb bioaccessibility values measured, presumably from their low dissolution during passage through the gastrointestinal tract. The results reported are highly relevant for smelter-originated environmental contamination scenarios in general.


Assuntos
Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Chumbo/análise , Poluentes do Solo/análise , Solo/análise , Extração em Fase Sólida/métodos , Disponibilidade Biológica , Criança , Pré-Escolar , Humanos , Lactente , Chumbo/sangue , Chumbo/química , Metalurgia , México , Microscopia Eletrônica de Varredura , Poluentes do Solo/sangue , Poluentes do Solo/química , Solubilidade , Difração de Raios X
20.
Int J Food Microbiol ; 286: 98-110, 2018 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-30056262

RESUMO

Foods and beverages are nutrient-rich ecosystems in which most microorganisms are able to grow. Moreover, several factors, such as physicochemical characteristics, storage temperature, culinary practices, and application of technologies for storage, also define the microbial population of foods and beverages. The yeast population has been well-characterised in fresh and processed fruit and vegetables, dairy products, dry-cured meat products, and beverages, among others. Some species are agents of alteration in different foods and beverages. Since the most comprehensive studies of spoilage yeasts have been performed in the winemaking process, hence, these studies form the thread of the discussion in this review. The natural yeast populations in raw ingredients and environmental contamination in the manufacturing facilities are the main modes by which food contamination occurs. After contamination, yeasts play a significant role in food and beverage spoilage, particularly in the alteration of fermented foods. Several mechanisms contribute to spoilage by yeasts, such as the production of lytic enzymes (lipases, proteases, and cellulases) and gas, utilisation of organic acids, discolouration, and off-flavours. This review addresses the role of yeasts in foods and beverages degradation by considering the modes of contamination and colonisation by yeasts, the yeast population diversity, mechanisms involved, and the analytical techniques for their identification, primarily molecular methods.


Assuntos
Contaminação de Alimentos/análise , Microbiologia de Alimentos , Leveduras/metabolismo , Bebidas/microbiologia , Laticínios/microbiologia , Manipulação de Alimentos , Frutas/microbiologia , Produtos da Carne/microbiologia , Verduras/microbiologia
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