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1.
Sci Total Environ ; 942: 173494, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-38810746

RESUMO

The soil is a vital resource that hosts many microorganisms crucial in biogeochemical cycles and ecosystem health. However, human activities such as the use of metal nanoparticles (MNPs), pesticides and the impacts of global climate change (GCCh) can significantly affect soil microbial communities (SMC). For many years, pesticides and, more recently, nanoparticles have contributed to sustainable agriculture to ensure continuous food production to sustain the significant growth of the world population and, therefore, the demand for food. Pesticides have a recognized pest control capacity. On the other hand, nanoparticles have demonstrated a high ability to improve water and nutrient retention, promote plant growth, and control pests. However, it has been reported that their accumulation in agricultural soils can also adversely affect the environment and soil microbial health. In addition, climate change, with its variations in temperature and extreme water conditions, can lead to drought and increased soil salinity, modifying both soil conditions and the composition and function of microbial communities. Abiotic stressors can interact and synergistically or additively affect soil microorganisms, significantly impacting soil functioning and the capacity to provide ecosystem services. Therefore, this work reviewed the current scientific literature to understand how multiple stressors interact and affect the SMC. In addition, the importance of molecular tools such as metagenomics, metatranscriptomics, proteomics, or metabolomics in the study of the responses of SMC to exposure to multiple abiotic stressors was examined. Future research directions were also proposed, focusing on exploring the complex interactions between stressors and their long-term effects and developing strategies for sustainable soil management. These efforts will contribute to the preservation of soil health and the promotion of sustainable agricultural practices.


Assuntos
Mudança Climática , Nanopartículas Metálicas , Praguicidas , Microbiologia do Solo , Nanopartículas Metálicas/toxicidade , Poluentes do Solo , Solo/química , Ecossistema , Microbiota/efeitos dos fármacos , Agricultura/métodos
2.
Pharmacol Res Perspect ; 11(2): e01070, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36914963

RESUMO

To investigate and compare the pharmacokinetic (PK) profiles of MB02 products, before and after optimizing the manufacturing process, and reference bevacizumab to establish bioequivalence between them. In this randomized, double-blind, single dose, parallel study, 114 healthy male volunteers were randomized 1:1:1 to receive a 1 mg/kg intravenous dose of MB02-SP, MB02-DM, or US-bevacizumab. The follow-up period was 100 days. PK similarity between them was determined using the standard bioequivalence criteria (0.80-1.25) for the area under the serum concentration-time curve from time 0 extrapolated to infinity and the maximum observed serum concentration. Study results showed that the PK profiles of bevacizumab were similar. Statistical analysis demonstrated that for each pairwise comparison there were no differences. The 90% CIs for the ratios of geometric least squares means were fully contained within the predefined similarity acceptance limits and ranged from 0.899 to 1.12 for area under the curve and from 0.887 to 1.11 for maximum concentration. A total of 159 adverse events were reported by 76 subjects who received the study drug. The majority (90.6%) of the reported adverse events were grade 1 in severity, with 9.4% as grade 2 in severity. None were considered as grade 3, 4, or 5. Treatment-induced anti-drug antibodies incidence was 21.6%, 33.3%, and 23.7% for the treatment of MB02-SP, MB02-DM, and US-bevacizumab, respectively. No subjects showed treatment-induced neutralizing anti-drug antibodies. This study demonstrates the PK, safety, and immunogenicity similarity and bioequivalence of MB02-SP, MB02-DM, and the reference product bevacizumab.


Assuntos
Medicamentos Biossimilares , Humanos , Masculino , Bevacizumab/efeitos adversos , Bevacizumab/farmacocinética , Equivalência Terapêutica , Administração Intravenosa , Método Duplo-Cego
3.
Trials ; 22(1): 674, 2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34600562

RESUMO

BACKGROUND: Moderate/severe cases of COVID-19 present a dysregulated immune system with T cell lymphopenia and a hyper-inflammatory state. This is a study protocol of an open-label, multi-center, double-arm, randomized, dose-finding phase I/II clinical trial to evaluate the safety, tolerability, alloreactivity, and efficacy of the administration of allogeneic memory T cells and natural killer (NK) cells in COVID-19 patients with lymphopenia and/or pneumonia. The aim of the study is to determine the safety and the efficacy of the recommended phase 2 dose (RP2D) of this treatment for patients with moderate/severe COVID-19. METHODS: In the phase I trial, 18 patients with COVID-19-related pneumonia and/or lymphopenia with no oxygen requirement or with an oxygen need of ≤ 2.5 liters per minute (lpm) in nasal cannula will be assigned to two arms, based on the biology of the donor and the patient. Treatment of arm A consists of the administration of escalating doses of memory T cells, plus standard of care (SoC). Treatment of arm B consists of the administration of escalating doses of NK cells, plus SoC. In the phase II trial, a total of 182 patients with COVID-19-related pneumonia and/or lymphopenia requiring or not oxygen supplementation but without mechanical ventilation will be allocated to arm A or B, considering HLA typing. Within each arm, they will be randomized in a 1:1 ratio. In arm A, patients will receive SoC or RP2D for memory T cells plus the SoC. In arm B, patients will receive SoC or RP2D for NK cells plus the SoC. DISCUSSION: We hypothesized that SARS-CoV-2-specific memory T-lymphocytes obtained from convalescent donors recovered from COVID-19 can be used as a passive cell immunotherapy to treat pneumonia and lymphopenia in moderate/severe patients. The lymphopenia induced by COVID-19 constitutes a therapeutic window that may facilitate donor engraftment and viral protection until recovery. TRIAL REGISTRATION: ClinicalTrials.gov NCT04578210 . First Posted : October 8, 2020.


Assuntos
COVID-19 , Linfopenia , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Humanos , Memória Imunológica , Células Matadoras Naturais , Linfopenia/diagnóstico , Linfopenia/terapia , Estudos Multicêntricos como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Linfócitos T , Resultado do Tratamento
4.
EClinicalMedicine ; 39: 101086, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34405140

RESUMO

BACKGROUND: Effective treatments are still needed to reduce the severity of symptoms, time of hospitalization, and mortality of COVID-19. SARS-CoV-2 specific memory T-lymphocytes obtained from convalescent donors recovered can be used as passive cell immunotherapy. METHODS: Between September and November 2020 a phase 1, dose-escalation, single centre clinical trial was conducted to evaluate the safety and feasibility of the infusion of CD45RA- memory T cells containing SARS-CoV-2 specific T cells as adoptive cell therapy against moderate/severe cases of COVID-19. Nine participants with pneumonia and/or lymphopenia and with at least one human leukocyte antigen (HLA) match with the donor were infused. The first three subjects received the lowest dose (1 × 105 cells/kg), the next three received the intermediate dose (5 × 105 cells/kg) and the last three received the highest dose (1 × 106 cells/kg) of CD45RA- memory T cells. Clinicaltrials.gov registration: NCT04578210. FINDINGS: All participants' clinical status measured by National Early Warning Score (NEWS) and 7-category point ordinal scales showed improvement six days after infusion. No serious adverse events were reported. Inflammatory parameters were stabilised post-infusion and the participants showed lymphocyte recovery two weeks after the procedure. Donor microchimerism was observed at least for three weeks after infusion in all patients. INTERPRETATION: This study provides preliminary evidence supporting the idea that treatment of COVID-19 patients with moderate/severe symptoms using convalescent CD45RA- memory T cells is feasible and safe. FUNDING: Clinical Trial supported by Spanish Clinical Research Network PT17/0017/0013. Co-funded by European Regional Development Fund/European Social Fund. CRIS CANCER Foundation Grant to AP-M and Agencia Valenciana de Innovación Grant AVI-GVA COVID-19-68 to BS.

5.
J Hazard Mater ; 390: 121974, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32062374

RESUMO

Silver nanoparticles (AgNPs) have attracted remarkable attention due to their powerful antimicrobial action as well as their particular physicochemical properties. This has led to their application in a wide variety of products with promising results. However, their interaction with the environment and toxicity in live terrestrial or aquatic organisms is still a matter of intense debate. More detailed knowledge is still required about the toxicity of AgNPs, their possible uptake mechanisms and their adverse effects in live organisms. Several studies have reported the interactions and potential negative effects of AgNPs in different organisms. In this review, we report and discuss the current state of the art and perspectives for the impact of AgNPs on different organisms present in the environment. Recent progress in interpreting uptake, translocation and accumulation mechanisms in different organisms and/or living animals are discussed, as well as the toxicity of AgNPs and possible tolerance mechanisms in live organisms to cope with their deleterious effects. Finally, we discuss the challenges of accurate physicochemical characterization of AgNPs and their ecotoxicity in environmentally realistic conditions such as soil and water media.


Assuntos
Poluentes Ambientais/toxicidade , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Animais , Organismos Aquáticos/efeitos dos fármacos , Humanos , Plantas/efeitos dos fármacos , Microbiologia do Solo
7.
Rev. cuba. med. trop ; 71(2): e353, mayo.-ago. 2019. tab, graf
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1093556

RESUMO

Introducción: Aedes aegypti (L) (Diptera: Culicidae), es una especie cosmopolita y vector de arbovirosis. Las variaciones de la temperatura y salinidad del agua influyen en la eclosión y supervivencia de fases larvales. Objetivo: Evaluar el efecto de diferentes temperaturas y salinidades en la eclosión de huevos y la supervivencia de larvas, pupas y adultos bajo condiciones de laboratorio. Métodos: Se colectaron larvas de Ae. aegypti, de reservorios artificiales en la zona periurbana de Puerto Vallarta, Jalisco, México, y se mantuvieron hasta la fase adulta. Los huevos obtenidos se sometieron a ocho temperaturas (15, 17, 20, 25, 27, 30, 32 y 35 °C). Se colocaron 15 huevos por quintuplicado y se evaluó la eclosión durante 96 h. Se colocaron 100 huevos con agua ajustada a 0.3, 2, 5, 10, 15,18 y 22 ups y se evaluó la eclosión hasta las 96 h. Adicionalmente se utilizaron larvas del estadio IV, por quintuplicado, sometiéndose a las mismas salinidades y se evaluó la supervivencia hasta las 48 h. El efecto de la salinidad en la ovoposición de las hembras se llevó a cabo introduciendo recipientes con las mismas concentraciones salinas, dentro en las jaulas entomológicas. Resultados: Se registró el 100 por ciento de eclosión a las 24 y 48 h; la temperatura de 35° C no registró eclosión. Las salinidades de 22 y 18 ups, provocaron mortalidad del 100 por ciento a las 24 h. En la salinidad de 15 ups, sobrevivió el 50 por ciento. Las concentraciones de 2, 5 y 10 ups demostraron 100 por ciento de supervivencia hasta la fase de adulto. La supervivencia de larvas del estadio IV en los tratamientos 2, 5 y 10 fue del 100 por ciento y en 15,18 y 22 ups disminuyó a 50, 80 y 100 por ciento, respectivamente (p˂ 0,05). Las diferentes concentraciones salinas no afectaron significativamente la ovoposición. La eclosión solo se presentó en las concentraciones de 0,3; 2; 5 y 10 ups. Los huevos ovopositados en concentraciones de 15, 18 y 22 ups no eclosionaron hasta que fueron transferidos a agua dulce con porcentajes de eclosión de entre el 80 y 90 por ciento. Conclusiones: Los embriones de Ae. aegypti poseen una amplia plasticidad para soportar cambios drásticos de temperatura y salinidad. El control efectivo de sus poblaciones debe incluir la revisión de charcas o reservorios que contengan aguas salobres hasta 18 ups(AU)


Introduction: Aedes aegypti (L) (Diptera: Culicidae) is a cosmopolitan species and a vector of arboviruses. Variations in the temperature and salinity of the water affect eclosion and survival during the larval stages. Objective: Evaluate the effect of different temperatures and salinities on the eclosion of eggs and the survival of larvae, pupae and adults in laboratory conditions. Methods: Ae. aegypti larvae were collected from artificial reservoirs in a peri-urban area of Puerto Vallarta, Jalisco, Mexico, and maintained until the adult stage. The eggs obtained were subjected to eight temperatures (15, 17, 20, 25, 27, 30, 32 and 35 °C). Fifteen eggs were placed in quintuplicate and eclosion was evaluated for 96 h. One hundred eggs were placed with water adjusted to 0.3, 2, 5, 10, 15, 18 and 22 psu and eclosion was evaluated until 96 h. Additionally, stage IV larvae were used in quintuplicate, subjecting them to the same salinities and evaluating survival until 48 h. The effect of salinity on oviposition by females was determined by introducing containers with the same salinity into the entomological cages. Results: 100 percent eclosion was recorded at 24 and 48 h, whereas no eclosion occurred at a temperature of 35 °C. Salinities of 22 and 18 psu caused 100 percent mortality at 24 h, whereas 50 percent survived at a salinity of 15 psu. At concentrations of 2, 5 and 10 psu 100 percent of the larvae survived until the adult stage. Survival of stage IV larvae in treatments 2, 5 and 10 was 100%, whereas in 15, 18 and 22 psu it fell to 50, 80 and 100 percent, respectively (p˂ 0.05). The different salinities did not affect oviposition significantly. Eclosion only occurred at concentrations of 0.3, 2, 5 and 10 psu. Oviposited eggs at concentrations of 15, 18 and 22 psu did not eclose until they were transferred to fresh water, where eclosion percentages ranged between 80 percent and 90 percent. Conclusions: Ae. aegypti embryos have great plasticity to endure drastic changes in temperature and salinity. Effective control of their populations should include inspection of ponds and reservoirs containing brackish water of up to 18 psu(AU)


Assuntos
Animais , Temperatura , Microbiologia da Água , Aedes/crescimento & desenvolvimento , Larva/microbiologia , Salinidade , Mosquitos Vetores/imunologia , Sobrevivência
8.
Sci Total Environ ; 670: 1068-1074, 2019 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-31018422

RESUMO

Copper nanoparticles (NCu) may co-exist with other pollutants in agricultural soils, such as pesticides. However, this has been little evaluated yet. Thus, possible effects of the simultaneous applications of pesticides and NCu on biogeochemical cycles are expected, for example on the nitrogen cycle. Therefore, the aim of this work was to evaluate the effect of simultaneous application of the herbicide atrazine (ATZ) and NCu on the abundance of total bacteria and nitrifying communities: ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB). Moreover, the ATZ dissipation was evaluated. A soil-plant system containing ATZ at field dose (3 mg a.i. kg-1) was mixed with two doses of NCu (0.05% or 0.15% w/w). Changes in the abundance of 16S rRNA and ammonia monooxygenase (amoA) genes of AOA and AOB were evaluated by real-time quantitative PCR (qPCR) at three sampling times (1, 15 and 30 days). The residual ATZ and nitrate production were also measured. The results showed significant differences in microbial composition and abundance over the 30 days of the experiment. Particularly, an initial decrease was observed in total bacterial abundance due to the presence of ATZ and NCu respect to ATZ alone (~60%). The abundance of AOA was also remarkably reduced (~85%), but these communities gradually recovered towards the end of the experiment. Conversely, AOB abundance initially increased (>100%) and remained mainly unaltered in soil exposed to ATZ and NCu 0.15% w/w, where nitrate formation was also constant. Moreover, NCu decreased the ATZ dissipation, which was translated in a 2-fold increase on the ATZ half-life values (T1/2). This study demonstrates that the simultaneous presence of NCu and ATZ may represent a risk for the total bacteria present in soil and sensitive microorganisms such as nitrifying communities, and changes in the dissipation of the pesticide could influence this process.


Assuntos
Archaea/fisiologia , Atrazina/efeitos adversos , Fenômenos Fisiológicos Bacterianos , Cobre/efeitos adversos , Herbicidas/efeitos adversos , Nanopartículas Metálicas/efeitos adversos , Poluentes do Solo/efeitos adversos , Genes Bacterianos , Ciclo do Nitrogênio , RNA Bacteriano/análise , RNA Ribossômico 16S/análise , Microbiologia do Solo
9.
J Hazard Mater ; 361: 228-236, 2019 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-30196035

RESUMO

Copper nanoparticles (NCu) have been proposed as an antimicrobial agent in agriculture. Therefore, NCu may interact with numerous pollutants including pesticides. Little is known about the combined effects of NCu and pesticides in soil. This study aimed at assessing the impact of NCu combined with the herbicide atrazine (ATZ) on soil. We focused on assessing the adsorption and dissipation of ATZ in the presence of NCu and the changes in microbial community profiles. First, ATZ adsorption isotherms (described using the Freundlich equation) were evaluated. After that, soil samples were spiked with NCu (40-60 nm) at 0.05 and 0.15% w/w and ATZ (3 mg a.i kg-1) and incubated for 30 days. The results showed that ATZ adsorption is favored by the presence of NCu. On the other hand, NCu at 0.15% w/w caused a significant decrease in ATZ dissipation, increasing its half-life from 6 to 37 days. Microbial community profiles (bacteria, fungi and nitrifying bacteria) remained relatively stable throughout the evaluated period. Therefore, our findings suggest that NCu can increase the persistence of ATZ in soil, which may be mostly associated to physical-chemical interaction with soil particles more than a microbial impact.


Assuntos
Atrazina/análise , Cobre/análise , Nanopartículas/análise , Praguicidas/análise , Microbiologia do Solo , Poluentes do Solo/análise , Atrazina/metabolismo , Biodegradação Ambiental , Cobre/metabolismo , Microbiota/efeitos dos fármacos , Nanopartículas/metabolismo , Praguicidas/metabolismo , Solo/química , Poluentes do Solo/metabolismo
10.
Crit Rev Biotechnol ; 39(2): 157-172, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30396282

RESUMO

Metal nanoparticles and metal oxides nanoparticles (MNPs/MONPs) have been widely included in a great diversity of products and industrial applications and they are already a part of our everyday life. According to estimation studies, their production is expected to increase exponentially in the next few years. Consequently, soil has been suggested as the main sink of MNPs/MONPs once they are deliberately or accidentally released into the environment. The potential negative perturbations that may result on soil microbial communities and ecological processes are resulting in concerns. Several nano-toxicological studies of MNPs/MONPs, reported so far, have focused on aquatic organisms, animals, and soil invertebrates. However, during recent years, the studies have been oriented to understand the effects of MNPs/MONPs on microbial communities and their interaction with soil components. The studies have suggested that MNPs/MONPs are one of the most toxic type to soil biota, amongst different types of nanomaterials. This may threaten soil health and fertility, since microbial communities are known to support important biological processes and ecosystem services such as the nutrient cycling, whereby their protection against the environmental pollution is imperative. Therefore, in this review we summarize the actual knowledge available from the last five years (2013-2018) and gaps about the potential negative, positive or neutral effects produced on soil by different classes of MNPs/MONPs. A particular emphasis has been placed on the associated soil microorganisms and biological processes. Finally, perspectives about future research are discussed.


Assuntos
Nanopartículas Metálicas , Metais , Óxidos , Microbiologia do Solo , Poluentes do Solo , Nanopartículas Metálicas/química , Nanopartículas Metálicas/toxicidade , Metais/química , Metais/toxicidade , Microbiota , Nanotecnologia , Óxidos/química , Óxidos/toxicidade , Solo/química , Poluentes do Solo/química , Poluentes do Solo/toxicidade
11.
J Fluoresc ; 29(1): 15-25, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30361861

RESUMO

The discoloration of methylene blue in aqueous solution was studied under illumination by a fluorescent lamp, LEDs of red, green, and blue light, and a UV-A black light bulb. Overall results showed that methylene blue was discolored with and without the presence of any photoactive semiconductor. Outcomes depended on the combination substrate-light source employed. Photosensitization was assumed as the discoloration mechanism followed upon visible light irradiation. Fluorescence spectroscopy and high-performance liquid chromatography were used to investigate the possible intermediates formed in the irradiated solutions. The detailed nature of formed species was not stablished, but it was proved that the dye molecule photo-bleached and partially defragmented in several intermediates including leuco dyes, demethylated phenothiazine dyes, and probably humic substances. Since the fluorescence intermediates found were similar for most of the irradiated solutions, it was assumed that comparable reactive species were responsible for the discoloration of the molecule in solution. Results proved the misconception of discoloration experiments found in the literature when employing visible light near the absorption region of the dye.

12.
Rev. clín. periodoncia implantol. rehabil. oral (Impr.) ; 10(3): 145-148, dic. 2017. tab, graf
Artigo em Inglês | LILACS | ID: biblio-900296

RESUMO

ABSTRACT: Aim: The objective of this work was to determine the concentrations of irrigating solutions and the residual content of parachloroaniline (PCA) formed after endodontic irrigation, using 5% NaOCl, 0.9% NaCl, 10% EDTA and 2% CHX 2%. Methodology Twenty premolars were used and 13 samples were collected per tooth from each of the treatment phases. Samples of: NaOCl, EDTA, CHX and PCA were quantified by UV and visible spectrophotometry. Results: Sodium hypochlorite decreased its concentration from 3.8% to 3.4% in phases 1 to 4. In phases 5, 6 and 7, residual NaOCl was measured with concentrations of 0.007%, 0.003% and 0.001% %. The concentration of EDTA decreased to 8.85% in phase 8. In phases 9, 10 and 11, irrigated with serum, EDTA was quantified with concentrations of 0.013% to 0.002% and NaOCl values of 0.0011% to 0, 0006%. In phases 12 and 13, CHX concentrations were 1.850% and 1.812% and PCA values were 0.0005% and 0.0007%. PCA formation occurred in presence of 2% CHX and residual NaClO and was detected colorimetrically in phases 12 and 13. Conclusions. During endodontic irrigation the concentration of 5% NaOCl decreases significantly in the first four phases and the concentrations of EDTA and CHX also decrease. There is PCA training in the last stages of the procedure.


Assuntos
Humanos , Irrigantes do Canal Radicular/química , Hipoclorito de Sódio/química , Clorexidina/química , Compostos de Anilina/análise , Irrigantes do Canal Radicular/administração & dosagem , Hipoclorito de Sódio/administração & dosagem , Espectrofotometria , Clorexidina/administração & dosagem , Ácido Edético/química , Interações Medicamentosas , Endodontia
13.
Epidemiol Infect ; 145(3): 568-574, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27834167

RESUMO

The importance of pork in the transmission of Salmonella spp. to humans has led to the development of control programmes worldwide. For this, knowledge on the epidemiology of the infection in the production system is fundamental to the efficacy of the regulations. Our objective was to determine the prevalence and spatial distribution of Salmonella-infected farms in the central region of Argentina, and to identify the predominant serotypes and epidemiological factors associated with an increased risk of infection. Salmonella was isolated from 22 of 52 sampled farms, for a farm prevalence of 42·3% (95% confidence interval 28·4-56·1). The most frequent serotypes isolated were S. Typhimurium and S. Derby, which have often been considered of public health concern in the region. Limited evidences of global and local clustering in the region under study were found, and the type of feed and presence of diarrhoeic pigs were significantly associated with having Salmonella shedders in the farm. This highlights the need to evaluate microbiological controls at the farm level, and demonstrates the usefulness of the spatial tools to identify areas of greatest risk when processing pork at slaughterhouse, which could contribute to increasing the food safety of pork products.


Assuntos
Salmonelose Animal/epidemiologia , Salmonelose Animal/microbiologia , Salmonella enterica/isolamento & purificação , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/microbiologia , Topografia Médica , Animais , Argentina/epidemiologia , Análise por Conglomerados , Prevalência , Fatores de Risco , Salmonella enterica/classificação , Sorogrupo , Análise Espacial , Suínos
14.
Vet Rec Open ; 2(2): e000117, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26495127

RESUMO

Because of the lack of information about both the genetic characteristics of Mycoplasma hyopneumoniae commercial vaccines and their relationship with field strains, the authors attempted to identify genetic subtypes of some M hyopneumoniae bacterins, and to compare them with M. hyopneumoniae field strains. Six commercial M hyopneumoniae bacterins and 28 bronchoalveolar lavages from pigs at slaughter from three herds were analysed by Multiple-Locus Variable number tandem repeat Analysis (MLVA) on p146R1, p146R3, H4, H5 and p95 loci. The results obtained showed the presence of more than one M hyopneumoniae genotype in some pigs and also in one of the bacterins analysed. It is also worth noting that MLVA typing allowed the distinction among circulating field strains and also when comparing them with vaccine strains, which, knowing the relatedness among them, could be useful in the research of the efficacy of the vaccines.

15.
J Nutrigenet Nutrigenomics ; 5(3): 117-31, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22965187

RESUMO

The salivary α-amylase is a calcium-binding enzyme that initiates starch digestion in the oral cavity. The α-amylase genes are located in a cluster on the chromosome that includes salivary amylase genes (AMY1), two pancreatic α-amylase genes (AMY2A and AMY2B) and a related pseudogene. The AMY1 genes show extensive copy number variation which is directly proportional to the salivary α-amylase content in saliva. The α-amylase amount in saliva is also influenced by other factors, such as hydration status, psychosocial stress level, and short-term dietary habits. It has been shown that the average copy number of AMY1 gene is higher in populations that evolved under high-starch diets versus low-starch diets, reflecting an intense positive selection imposed by diet on amylase copy number during evolution. In this context, a number of different aspects can be considered in evaluating the possible impact of copy number variation of the AMY1 gene on nutrition research, such as issues related to human diet gene evolution, action on starch digestion, effect on glycemic response after starch consumption, modulation of the action of α-amylases inhibitors, effect on taste perception and satiety, influence on psychosocial stress and relation to oral health.


Assuntos
Variações do Número de Cópias de DNA , alfa-Amilases Salivares/genética , Animais , Sequência de Bases , Dieta , Genômica , Humanos , Hiperglicemia , Mastigação , Modelos Genéticos , Dados de Sequência Molecular , Família Multigênica , Nutrigenômica , Ciências da Nutrição , Pan troglodytes , Ratos , Homologia de Sequência do Ácido Nucleico , Amido/metabolismo , Estresse Psicológico , Fatores de Tempo
16.
Bioresour Technol ; 118: 603-6, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22704830

RESUMO

Phytase production by Aspergillus niger F3 by solid state fermentation (SSF) on citrus peel was evaluated at pilot scale under different aeration conditions. The best airflow intensity was 1 VkgM (Lair kg medium(-1) min(-1)), which allowed to produce 65 units of phytases per gram in dry basis (65 Ug(-1) d.b.) as it removed the metabolic heat generated by the microorganism, Agitation did not improve heat removal. Airflow intensity was considered as scale-up criterion. When the airflow intensity was maintained at 1 VkgM for SSF with 2 and 20 kg of medium, the kinetics parameters for biomass and enzyme concentration at the end of fermentation differed by less than 2. The air flow intensity was required to maintain the temperature and cool the SSF and to provide oxygen for microbial growth. Air flow intensity is a key a factor that must be considered when scale-up of SSF is attempted.


Assuntos
6-Fitase/biossíntese , Movimentos do Ar , Aspergillus niger/enzimologia , Biotecnologia/métodos , Fermentação/fisiologia , Aerobiose , Temperatura Alta , Cinética
17.
Water Sci Technol ; 63(11): 2478-85, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22049738

RESUMO

A comparison of two different medium scale MBRs (ultrafiltration and microfiltration) using respirometric methods has been achieved. The ultrafiltration membrane plant (0.034 microm pore size) maintained recirculation sludge flow at seven times the influent flow, and membranes were backwashed every 5 min and chemically cleaned weekly. The microfiltration membrane plant (0.4 microm pore size) maintained recirculation sludge flow at four times the influent flow, membrane-relax was applied after the production phase and membranes were chemically cleaned in the event of high trans-membrane pressure. Both technologies showed a similar performance with regard to heterotrophic kinetic and stoichiometric parameters and organic matter effluent concentrations. The influent was characterized by means of its COD fractions and the average removal percentages for COD concentrations were around 97% for both plants in spite of influent COD fluctuation, temperature variations and sludge retention time (SRT) evolution. Both SRT evolution and temperature affect the heterotrophic yield (Y(H)) and the decay coefficient (bH) in the same range for both plants. Y(H) values of over 0.8 mg COD/mg COD were obtained during the unsteady periods, while under steady state conditions these values fell to less than 0.4 mg COD/mg COD. bH by contrast reached values of less than 0.05 d(-1).


Assuntos
Filtração/métodos , Consumo de Oxigênio , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Biomassa , Reatores Biológicos , Cinética , Projetos Piloto , Esgotos/microbiologia , Temperatura , Poluentes Químicos da Água/química
18.
Food Sci Technol Int ; 17(3): 187-204, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21593288

RESUMO

Starch is the most important source of energy for humans, and it is present in many products derived from cereals, legumes and tubers. Interestingly, some of these food products can have different metabolic effects (e.g. change of postprandial blood glucose concentration) although the total amount of starch is the same. This review focuses on a microstructural perspective of the glycemic response, in search of an alternative and complementary explanation of this phenomenon. Several starch and food microstructures are responsible for the change in starch bioaccessibility. Aspects such as the characterization of the microstructure of starchy products and, its relation to the metabolic problem, the crucial role of the food matrix and other components in the ingested meal, and the gaps in our present knowledge are discussed.


Assuntos
Glicemia/efeitos dos fármacos , Carboidratos da Dieta/análise , Carboidratos da Dieta/metabolismo , Análise de Alimentos , Amido/química , Amido/metabolismo , Humanos , Fenômenos Fisiológicos da Nutrição
19.
Transplant Proc ; 42(10): 4295-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21168686

RESUMO

Although respiratory viral infections have been associated with acute rejection and bronchiolitis obliterans syndrome, the long-term impact of the novel pandemic influenza A (2009 H1N1) virus on lung transplant patients has not been defined. We describe the diagnostic challenges and long-term consequences of 2009 H1N1 infection in a lung transplant patient, discuss the potential implications for prevention and treatment, and conclude that even timely antiviral therapy may be insufficient to prevent long-term morbidity.


Assuntos
Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Influenza Humana/diagnóstico , Transplante de Pulmão , Adulto , Antivirais/uso terapêutico , Biópsia , Fibrose Cística/cirurgia , Feminino , Humanos , Influenza Humana/tratamento farmacológico , Influenza Humana/patologia , Influenza Humana/prevenção & controle
20.
Vaccine ; 28(32): 5185-96, 2010 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-20558243

RESUMO

Intranasal immunization was assayed in C57BL/6 mice against Angiostrongylus costaricensis using a synthetic and a recombinant peptide belonging to the catalytic region of the serine/threonine phosphatase 2 A (PP2A) of the parasite. Immunization was carried out with the synthetic peptide (SP) polymerized either with itself or with the beta fraction of the cholera toxin (CTB) and then enclosed in nanocapsules of phosphatidyl choline, cholesterol and Quil A (ISCOM). Another group of mice was immunized with recombinant peptide. Immunization consisted of two intranasal inoculations at two-week intervals, and the challenge with L3 larvae was made one month after the last vaccination. The effectiveness of immunization was evaluated 30 days after infection by analysis of the number of parasites in the arteries of the immunized mice, as well as by measuring spleen sizes in the experimental groups. The response induced was determined by identifying the isotypes of IgG as well as the IgE and IgA specific antigen response. The interleukins produced by the splenocyte culture of the different groups were assessed after exposing them to the peptide used in the immunization. From our results, 60%, 80%, and 100% protection against the A. costaricensis challenge was achieved in mice immunized with polymerized synthetic peptide in ISCOM, synthetic peptide polymerized with the CTB in ISCOM and inclusion bodies respectively. Splenomegaly was found to be less evident in the immunized mice than in the controls. A significant increase in IFN gamma and IL-17 levels was observed in the group with 100% protection. The results showed that vaccination through the nasal mucosa may constitute a useful method of immunization and result in a protective immune response against A. costaricensis.


Assuntos
Antígenos de Helmintos/imunologia , Proteína Fosfatase 2/imunologia , Infecções por Strongylida/prevenção & controle , Vacinas Sintéticas/imunologia , Administração Intranasal , Sequência de Aminoácidos , Angiostrongylus/enzimologia , Angiostrongylus/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Sequência de Bases , Toxina da Cólera/imunologia , Feminino , ISCOMs/imunologia , Interleucinas/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Nanocápsulas , Mucosa Nasal/imunologia , Tamanho do Órgão , Baço/citologia , Baço/imunologia , Infecções por Strongylida/imunologia
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