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1.
J Appl Microbiol ; 132(2): 1457-1466, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34465011

RESUMO

AIMS: To generate a murine experimental model of colonization by Campylobacter coli DSPV458. METHODS AND RESULTS: Twelve adult Balb/cCmedc female mice were housed in a treated group (T-G) and a control group (C-G) for 4 weeks. Both experimental groups received antibiotics for 5 days during the first week. The T-G was administered with 6.68log10 CFU of C. coli DSPV458 by oesophageal gavage. Necropsies were performed weekly to evaluate translocation and intestinal colonization in the spleen and liver and in the ileum and cecum respectively. Samples were cultured to quantify intestinal microbiota members. Faeces were cultured weekly for a C. coli DSPV458 count. Campylobacter coli DSPV458 was isolated from all the inoculated mice. The recovered level of C. coli DSPV458 was, on average, 6.9 log10 CFUg-1 , 8.0 log10 CFUg-1 and 1.6 log10 CFUg-1 in faeces, cecum and ileum respectively. Colonization by C. coli DSPV458 does not alter the normal clinical and physiological status. CONCLUSIONS: Campylobacter coli DSPV458 does not have an invasive capacity, and the model is suitable for evaluating strategies to reduce intestinal loads. SIGNIFICANCE AND IMPACT OF STUDY: Farm animals have an important impact on thermotolerant Campylobacter transmission to humans. Extremely few colonization models by C. coli have been reported to date. In food-producing animals, infection is mild or absent and thermotolerant Campylobacter colonize the intestines of animals. Colonization models are specific models that do not cause infection as they do not generally result in diarrhoea or other signs of disease. Therefore, this model will allow to evaluate the evolution of colonization by thermotolerant Campylobacter and the alternative tools development to antibiotics that limit their colonization in food-producing animals.


Assuntos
Infecções por Campylobacter , Campylobacter coli , Campylobacter jejuni , Campylobacter , Animais , Campylobacter/genética , Infecções por Campylobacter/veterinária , Campylobacter coli/genética , Ceco , Fezes , Feminino , Intestinos , Camundongos
2.
Benef Microbes ; 12(6): 553-565, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34590533

RESUMO

Thermotolerant Campylobacter species are the leading cause of foodborne bacterial diarrheal disease worldwide. Campylobacter coli, abundant in pigs and pork products, have been identified as a source of human infection. In this study, we propose the use of Lactiplantibacillus plantarum LP5 as a probiotic to reduce colonisation of this intestinal pathogen in a murine colonisation model of C. coli DSPV458. Six-week-old adult female Balb/cCmedc mice were housed in groups: Control, Campy and Pro-Campy. Control and Pro-Campy groups received antibiotics for 5 days and the Campy group for 12 days. Pro-Campy group was inoculated for 7 days with 8.78 log10 cfu total of L. plantarum LP5 suspended in De Man, Rogosa and Sharpe broth. All groups were inoculated with 6.72 log10 cfu of C. coli DSPV458 suspended in brain heart infusion broth. L. plantarum LP5 was recovered only in the Pro- Campy group. C. coli DSPV458 was recovered at higher levels in the Control and Campy groups. The differences with the Pro-Campy group were significant. As regards faeces, Control and Campy groups reached 7.41 and 7.84 log10 cfu/g, respectively, and the Pro-Campy group only 4.62 log10 cfu/g. In the caecum, Control and Campy groups reached 8.01 and 9.26 log10cfu/g, respectively, and the Pro-Campy group only 4.51 log10 cfu/g. In the ileum, Control and Campy groups reached 3.43 and 3.26 log10 cfu/g, respectively, and the Pro-Campy group did not show detectable levels. The reduction of C. coli DSPV458 in the Pro-Campy group compared to the Control group in faeces, caecum and ileum was 99.55, 99.98 and 100%, respectively. Animals were maintained under normal health conditions, and haematological parameters were within the standard values for Balb/cCmedc. The incorporation of a probiotic generated a protective effect in the mice colonisation model. The protective effect would also apply to intestinal colonisation by indigenous enterobacteria. Therefore, the strategy used in this study is of great importance to understand the protection mechanisms in a murine model, as well as its application in food-producing animals.


Assuntos
Infecções por Campylobacter/terapia , Intestinos/microbiologia , Lactobacillus plantarum , Probióticos , Animais , Campylobacter coli , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Fezes , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Probióticos/uso terapêutico , Suínos
3.
Arch Microbiol ; 203(7): 4161-4171, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34061232

RESUMO

The objective of this work was to determine the antibacterial effect of Lactobacillus plantarum strains of pork origin against Campylobacter coli strains, and to conduct experimental colonization pilot models in mice for both microorganisms. Inhibition assays allowed evaluation and selection of L. plantarum LP5 as the strain with the highest antagonistic activity against C. coli and with the best potential to be used in in vivo study. Adult 6-week-old female Balb/cCmedc mice were lodged in two groups. The treated group was administered with 9.4 log10CFU/2 times/wk of L. plantarum LP5. L. plantarum LP5 was recovered from the feces and cecum of the inoculated mice. However, when bacteria stopped being administered, probiotic counts decreased. Experimental colonization with C. coli was carried out in five groups of mice. All animals were treated with antibiotics in their drinking water to weaken the indigenous microbiota and to allow colonization of C. coli. Four groups were administered once with different C. coli strains (DSPV458: 8.49 log10CFU; DSPV567: 8.09 log10CFU; DSPV570: 8.46 log10CFU; DSPV541: 8.86 log10CFU, respectively). After 8 h, mice inoculated with different C. coli strains were colonized because the pathogen was detected in their feces. L. plantarum LP5 tolerated the gastrointestinal conditions of murine model without generating adverse effects on the animals. C. coli DSPV458 colonized the mice without causing infection by lodging in their digestive tract, thus generating a reproducible colonization model. Both models combined could be used as protection murine models against pathogens to test alternative control tools to antibiotics.


Assuntos
Antibiose , Campylobacter coli , Lactobacillus plantarum , Probióticos , Animais , Campylobacter coli/fisiologia , Fezes/microbiologia , Feminino , Trato Gastrointestinal/microbiologia , Lactobacillus plantarum/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Modelos Animais , Probióticos/metabolismo
4.
Infect Genet Evol ; 81: 104207, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-31991176

RESUMO

During the acute phase of HIV-1 infection, a strong readaptation occurs in the viral population. Our objective was to analyze the post-transmission mutations associated with escape to the cytotoxic immune response and its relationship with the progression of the infection. In this study, a total of 17 patients were enrolled during acute/early primary HIV infection and 8 subjects that were the HIV positive partner resulting in 8 transmission pairs. Genotyping of the genetic polymorphisms of HLA class I A and B was performed using PCR-SSOP. Viral RNA extraction was from plasma. 570 single Gag-gene amplifications were obtained by limiting-dilution RT-PCR. Epitope prediction was performed with NetMHC CBS prediction server for the 19 HLA-A and B alleles. Cytotoxic response prediction was performed by using the IEDB Analysis Resource. From our results, we deduce that the transmitted CTL / gag escape frequency in the founder virus was at least double compared to the post-transmission events. Additionally, by means of an algorithm that combines these frequencies, we observed that the founder viruses better adapted to the HLA A / B alleles of the recipient could contribute to a greater progression of the infection. Our results suggest that there is a large adaptation of HIV-1 to the HLA A / B alleles prevalent in our population. However, despite this adaptive advantage, the virus needs to make "readjustments" through new escape and compensatory mutations. Interestingly, according to our results, this readaptation could have a role in the progression of the infection.


Assuntos
Infecções por HIV/virologia , HIV-1/genética , Adulto , Alelos , Argentina , Biologia Computacional , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/imunologia , Feminino , Genótipo , Infecções por HIV/imunologia , HIV-1/imunologia , Humanos , Masculino , Mutação/genética , Mutação/imunologia , RNA Viral/genética , RNA Viral/imunologia , Linfócitos T Citotóxicos/imunologia , Produtos do Gene gag do Vírus da Imunodeficiência Humana/genética , Produtos do Gene gag do Vírus da Imunodeficiência Humana/imunologia
5.
Bull Entomol Res ; 109(2): 178-190, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29784067

RESUMO

Anastrepha fraterculus (Wiedemann), a pest of great economic importance in South America, needs urgently to be controlled by environmentally friendly methods such as the sterile insect technique for which mass rearing of insects is required. Because oogenesis takes place during the adult stage, mass-rearing facilities should provide the females a diet that maximizes egg production at the lowest cost. Accordingly, we investigated the effect of artificial protein sources in the adult diet (yeast derivatives of different cost but with similar amino acids profiles, and the addition of wheat germ) on fecundity. Additionally, we evaluated different ratios of yeast derivatives or wheat germ on ovary maturation, fecundity, and fertility as well as their association with the nutrient content of females. Females fed hydrolyzed yeast and yeast extract attained the highest fecundity level, and those fed brewer's yeast the lowest. Reducing the amount of hydrolyzed yeast, an expensive protein source, in the diet negatively affected fecundity and ovary maturation. Increasing the amount of brewer's yeast, a low-cost protein source, did not favor fecundity. The addition of wheat germ in the adult diet improved fecundity regardless of the yeast derivate considered. Percentage of egg hatch was not affected by the diet. Nutrient content of A. fraterculus females varied according to the adult diet provided and mating status. Our findings provide novel baseline information to understand the role of nutrition on reproductive performance of A. fraterculus females and are discussed in the context of resource allocation. They also provide valuable advances in the search for cost-effective adult diets at fruit fly mass rearing facilities.


Assuntos
Dieta , Oviparidade , Tephritidae/fisiologia , Animais , Feminino , Fertilidade , Ovário/fisiologia , Triticum , Leveduras
6.
J Insect Physiol ; 57(12): 1622-30, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21896276

RESUMO

This work tested if carbohydrates and proteins ingestion is regulated in the South American fruit fly, Anastrepha fraterculus, to optimize survival and reproduction. Adult food treatments were established by providing sugar and hydrolyzed yeast in various combinations either alone or mixed at a standard 3:1 ratio (sugar:hydrolyzed yeast). Individual food consumption was assessed and related to survival patterns. The effects of adult feeding on fecundity and fertility patterns were investigated in groups of flies. Sugar consumption was the lowest in the treatment where it was provided with hydrolyzed yeast at a fixed 3:1 ratio. Consumption of hydrolyzed yeast did not differ between this treatment and the one in which this solution was complemented with one solution of sugar. It seems that a mixture of sugar and hydrolyzed yeast at a fixed ratio of 3:1, respectively, restricts extra ingestion of sugar; most probably because of negative response of the fly to overconsumption of protein. Survival was affected by the treatments, being lower in those cases where protein was at the fixed ratio. Group experiments revealed that protein restriction expanded longevity and decreased egg production. In contrast, egg production was enhanced when flies were kept continuously with a mixture of yeast and sugar plus an extra source of sugar, and this was not in detriment of survival. Our results suggest that fixed sugar-protein ratios in which protein is in excess affects fitness components such as longevity and reproduction. These findings are discussed from a theoretical and applied perspective in the context of pest control by means of the sterile insect technique.


Assuntos
Dieta com Restrição de Proteínas , Preferências Alimentares , Longevidade , Oviparidade , Tephritidae/fisiologia , Animais , Carboidratos da Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Feminino , Masculino
7.
Clin Transl Oncol ; 12(4): 292-8, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20462839

RESUMO

INTRODUCTION: A survey regarding radiobiological questions in the treatment of lung cancer (LC) was done to study the clinical aspects of radiotherapy in Spain, in order to standardise treatment decisions. METHODS AND MATERIALS: From November 2007 to March 2008, a survey was performed among radiation oncologists in Spain specialising in LC treatment via e-mail, which included questions regarding different radiobiological aspects of radiotherapy LC treatment. The extent of the resulting material made it necessary to divide it into two parts; the first is presented in this article. The second, which includes items about alpha/beta-NTCP/TCP values and reirradiation criteria, will be reported elsewhere. RESULTS: Thirty-one radiation therapists from 29 radiation oncology departments answered the survey. 77.4-93.5% of responders used the basic formula from the linear-quadratic model and/or computer software for radiobiological calculations; 100% used lung (mostly V20, median <30%) and spinal cord constraints (mostly a median of physical maximum dose <45.5 Gy); and 90.3% used heart and oesophagus constraints (very heterogeneous parameters in both organs). CONCLUSIONS: Radiobiological considerations are clearly present in the planning process of radiotherapy of LC in Spain, with a high coincidence with the literature regarding lung and spinal cord constraints. The heterogeneity shown for oesophagus and heart results demonstrates the need for continuing investigation into the standardisation of clinical, dosimetric and radiobiologic aspects of the treatment of this cancer.


Assuntos
Neoplasias Pulmonares/radioterapia , Padrões de Prática Médica/estatística & dados numéricos , Padrões de Prática Médica/normas , Radioterapia (Especialidade)/estatística & dados numéricos , Radioterapia (Especialidade)/normas , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos , Coleta de Dados , Humanos , Radioterapia (Especialidade)/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Planejamento da Radioterapia Assistida por Computador/normas , Espanha
8.
Anal Bioanal Chem ; 393(6-7): 1733-43, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19198813

RESUMO

In this stir bar sorptive extraction (SBSE) method, 16 pesticides were extracted from surface water samples by sorption onto 1 mm polydimethylsiloxane layer coated on a 10-mm-length stir bar magnet. After liquid desorption of the analytes with 1 ml of methanol, the detection was performed on a liquid chromatography-tandem mass spectrometry with a triple quadrupole (QqQ) analyzer using selected reaction monitoring mode via electrospray ionization. Parameters affecting SBSE operation, including sample volume, salt addition, extraction time, stirring rate, and desorption conditions, have been evaluated. The optimized SBSE method required two 50 ml aliquots of surface water samples, one aliquot was added of 30% NaCl and stirred at 900 rpm during 1 h for testing five pesticides with log K(o/w) < 3, and the other aliquot was directly extracted following the same procedure for the rest of the pesticides with log K(o/w) > 3. The method was validated in spiked surface water samples at limits of quantifications (LOQs) and ten times the LOQs showing recoveries <62%, and the LOQs reached were from 0.03 microg l(-1) for diazinon to 3 microg l(-1) for simazine. The proposed methodology was applied to the determination of these compounds in samples from Albufera Lake and surrounding channels, showing that SBSE is a powerful tool for routine control analysis of pesticide residues in surface water.


Assuntos
Fracionamento Químico/métodos , Água Doce/química , Resíduos de Praguicidas/análise , Cromatografia Líquida/métodos , Diazinon/análise , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Simazina/análise , Cloreto de Sódio/química , Espectrometria de Massas em Tandem/métodos
9.
Rev Biol Trop ; 44(2A): 653-7, 1996 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-9246371

RESUMO

A culture system, consisting of a semi-rigid net, with an ABS frame filled with styrofoam was used for the culture of the Pacific oyster Crassostrea gigas, from 3.0 mm length seed. The culture system was tested in three locations, two inside San Quintín Bay and one in San Martín Island. The mean monthly growth was 8.69 mm and 8.96 mm in the Bay and 7.33 mm in San Martín Island. These growth rates show that this species can attain commercial sizes in 6 months, using the culture system tested.


Assuntos
Ostreidae/crescimento & desenvolvimento , Animais , México
10.
Oncol. (Quito) ; 2(1): 7-12, jun. 1994.
Artigo em Espanhol | LILACS | ID: lil-235389

RESUMO

Presenta la experiencia del Hospital 12 de Octubre sobre el tratamiento conservador del cáncer del seno, durante el período de observación de 1978 a 1990 que alcanza 218 pacientes. Propicia este tratamiento como la línea más racional, como garantía de la calidad asistencial, ya que mutilación no es sinónimo de curación y la extirpación contribuye a crear insatisfacción e imperfección. Apoyábamos el tratamiento no mutilante en los resultados obtenidos por otros autores, así como en nuestra propia experiencia, pero no consignábamos todavía los resultados de estudios randomizados. Considerábamos la terapéutica conservadora como la sumación de esfuerzos quirúrgicos (tumurectomía y vaciamiento axilar) y radioterápicos (irradicación de la mama y en ocasiones de las áreas ganglionares) e implicábamos los tratamientos sistémicos en dependencia de factores pronósticos específicos para cada caso...


Assuntos
Feminino , Neoplasias da Mama/terapia , Radioterapia , Pacientes
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