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1.
mSphere ; 8(1): e0026322, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36598226

RESUMO

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus is thought to have originated in wild bats from Asia, and as the resulting pandemic continues into its third year, concerns have been raised that the virus will expand its host range and infect North American wildlife species, including bats. Mexican free-tailed bats (Tadarida brasiliensis) live in large colonies in the southern United States, often in urban areas and, as such, could be exposed to the virus from infected humans. We experimentally challenged wild T. brasiliensis with SARS-CoV-2 to determine the susceptibility, reservoir potential, and population impacts of infection in this species. Of 10 bats oronasally inoculated with SARS-CoV-2, 5 became infected and orally excreted moderate amounts of virus for up to 18 days postinoculation. These five subjects all seroconverted and cleared the virus before the end of the study with no obvious clinical signs of disease. We additionally found no evidence of viral transmission to uninoculated subjects. These results indicate that while T. brasiliensis are susceptible to SARS-CoV-2 infection, infection of wild populations of T. brasiliensis would not likely cause mortality. However, the transmission of SARS-CoV-2 from T. brasiliensis to or from humans, or to other animal species, is a possibility requiring further investigation to better define. IMPORTANCE As the COVID-19 pandemic has continued for 3+ years, there has been increasing concern that the SARS-CoV-2 virus will enter wildlife populations and potentially create new reservoirs where the virus could adapt to a new host and create variants. This is particularly possible with species that reside in man-made structures, in proximity to infected human populations. Mexican free-tailed bats (Tadarida brasiliensis) live in large colonies, often in urban settings and, thus, can be exposed by infected humans and potentially transmit the virus to new hosts. We experimentally challenged T. brasiliensis with SARS-CoV-2 and revealed that they are susceptible to the virus and excrete moderate amounts for up to 18 days postinoculation. This is important information for wildlife biologists, wildlife rehabilitation workers, and the general public that may contact these animals.


Assuntos
COVID-19 , Quirópteros , Animais , Humanos , SARS-CoV-2 , Pandemias , Animais Selvagens
2.
bioRxiv ; 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35898345

RESUMO

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus originated in wild bats from Asia, and as the resulting pandemic continues into its third year, concerns have been raised that the virus will expand its host range and infect North American wildlife species, including bats. Mexican free-tailed bats ( Tadarida brasiliensis : TABR) live in large colonies in the southern United States, often in urban areas, and as such, could be exposed to the virus from infected humans. We experimentally challenged wild TABR with SARS-CoV-2 to determine the susceptibility, reservoir potential, and population impacts of infection in this species. Of nine bats oronasally inoculated with SARS-CoV-2, five became infected and orally excreted moderate amounts of virus for up to 18 days post inoculation. These five subjects all seroconverted and cleared the virus before the end of the study with no obvious clinical signs of disease. We additionally found no evidence of viral transmission to uninoculated subjects. These results indicate that while TABR are susceptible to SARS-CoV-2 infection, infection of wild populations of TABR would not likely cause mortality. However, the transmission of SARS-CoV-2 from TABR to or from humans, or to other animal species, is a distinct possibility requiring further investigation to better define.

3.
Food Chem ; 271: 309-317, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30236682

RESUMO

In the present work it was analyzed the water mobility by characterizing the thermo-gravimetric analysis of the cookie dough with the incorporation of dietary fibers. The fibers analyzed were: inulin (IN), oat fiber (OF), high amylose maize starch (RSII) and phosphate distarch-phosphate (RSIV). Four tests were performed: thermo-gravimetric analysis (TGA), pasting profile analysis using water and a solution of 50% sucrose as a solvent, and the study of the ultrastructure of the flour and fiber by SEM and particle size distribution. Changes in the thermo-gravimetric profile were explained by the pasting profile of composites and the ultrastructure of the wheat flour and fibers. OF and IN incorporation changed substantially dough water loss profile and rate. The addition of fibers produced a decrease in the starch pasting profile and inulin showed the highest reduction since less water was available for the hydration of wheat flour starch granules.


Assuntos
Fibras na Dieta , Água/química , Farinha , Amido , Temperatura , Triticum
4.
Food Chem ; 192: 950-7, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26304434

RESUMO

The effect of fiber addition on the distribution and mobility of protons in biscuits is studied by using low resolution time domain nuclear magnetic resonance (TD-NMR). The proportion of flour is reduced in order to incorporate inulin and oat fiber. NMR temperature dependent experiments are carried out in order to gain insight on the processes occurring in biscuit baking. Proton populations were identified measuring spin-spin relaxation times (T2). The major change in the relaxation profiles upon incorporation of fibers corresponds to mobile water molecules, which appear to be related to dough spreading behavior and biscuit quality. Biscuit samples baked in a commercial oven were studied by two dimensional spin-lattice/spin-spin (T1-T2) relaxation maps. The T1/T2 ratio is used as an indicator of the population mobility, where changes in the mobility of water in contact with flour components as starch, proteins and pentosans are observed.


Assuntos
Fibras na Dieta/análise , Farinha/análise , Espectroscopia de Ressonância Magnética/métodos , Prótons , Avena/química , Proteínas Alimentares/química , Tecnologia de Alimentos , Inulina/química , Amido/química , Água/química
5.
Food Sci Technol Int ; 17(3): 213-21, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21593287

RESUMO

The development of dietary fiber-enriched foods permits to obtain products with functional properties but can cause several problems in technological quality. The aim of this study was to study the quality of pasta obtained by replacing bread wheat flour with resistant starch II (RSII), resistant starch IV (RSIV), oat bran (OB) and inulin (IN) with the purpose of improving their nutritional quality. RSII, RSIV, OB and IN were substituted for a portion of bread wheat flour at levels 2.5%, 5.0%, 7.5% and 10.0%. Cooking properties, amylose and inulin losses, color and texture were measured. Finally, nutritional quality of enriched pasta was evaluated by protein losses during cooking and total dietary fiber. Microstructure of pasta was analyzed by scanning electron microscopy. Addition of RSII into pasta formulation improved the quality of the final product. RSIV-enriched pasta presented an improvement in textural characteristics and OB affected cooking properties positively up to 5% of substitution. Inulin was lost during cooking; besides, its addition negatively affected the technological quality of pasta. The results obtained in this study prove that it is possible to elaborate pasta with acceptable cooking quality and with improved nutritional characteristics by adding 10% of RSII and RSIV and 5% of OB.


Assuntos
Fibras na Dieta , Análise de Alimentos , Culinária , Proteínas Alimentares , Farinha , Inulina/química , Microscopia Eletrônica de Varredura , Triticum , Água/química
6.
J Med Food ; 6(4): 397-9, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14977451

RESUMO

In this work we evaluated the efficacy and safety of a bread formulation containing chitosan in dyslipidemic type 2 diabetic subjects. For this purpose a total of 18 patients were allowed to incorporate to their habitual diets 120 g/day of bread containing 2% (wt/wt) chitosan (chitosan group, n= 9) or standard bread (control group, n= 9). Before the study and after 12 weeks on the modified diet, the following parameters were evaluated: body weight, plasma cholesterol, high-density lipoprotein (HDL)-cholesterol, low-density lipoprotein (LDL)-cholesterol, triglyceride, and hemoglobin A(1c) (HbA(1c)). Compared with the control group, the patients receiving chitosan-containing bread decreased their mean levels of LDL-cholesterol and significantly increased their mean levels of HDL-cholesterol at the end of the study. There were no significant differences in the body weight, serum triglyceride, and HbA(1c). These results suggest that chitosan incorporated into bread formulations could improve the lipoprotein balance similar to typical biliary salts trappers, increasing the HDL- and lowering the LDL-cholesterol, without changing the triglyceride levels. These results warrant further studies over a longer period of time to evaluate if a persistent improvement in levels of lipoproteins can be attained with this strategy.


Assuntos
Pão , Quitina/análogos & derivados , Quitina/administração & dosagem , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/dietoterapia , Hiperlipidemias/dietoterapia , Glicemia/metabolismo , Peso Corporal/efeitos dos fármacos , Quitina/efeitos adversos , Quitosana , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Aditivos Alimentares/farmacologia , Aditivos Alimentares/uso terapêutico , Hemoglobinas Glicadas/análise , Humanos , Hiperlipidemias/sangue , Hiperlipidemias/complicações , Resultado do Tratamento , Triglicerídeos/sangue
7.
J Agric Food Chem ; 49(2): 913-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11262049

RESUMO

The effects of freezing and storage in frozen conditions on bread quality, crumb properties, and aggregative behavior of glutenins were analyzed. The effect of different additives on bread quality was also studied. The results obtained showed that freezing and storage at -18 degrees C decreased the bread quality. Samples stored in frozen conditions supplemented with diacetyl-tartaric acid ester of monoglycerides, gluten, and guar gum produced breads of greater volume and more open crumb structure than those prepared with the base formulation (without additives). All additives analyzed increased the proof time. Crumb firmness increased with dough frozen storage and bread aging time at 4 degrees C. A decrease in the amount of glutenin subunits of high molecular mass was observed by electrophoresis analysis of the SDS-soluble proteins aggregates extracted from the frozen dough. This result suggested that the protein matrix of bread underwent depolymerization during storage in frozen conditions.


Assuntos
Pão/normas , Alimentos Congelados/normas , Glutens/análogos & derivados , Culinária , Aditivos Alimentares , Congelamento , Glutens/química , Fatores de Tempo
8.
Epilepsia ; 32(3): 310-21, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1904342

RESUMO

Centromedian thalamic nuclei (CM) epileptiform EEG activities were recorded in children with intractable generalized seizures of Lennox-Gastaut syndrome (LGS) through implanted recording-stimulating electrodes used for seizure control. Ictal CM epileptiform activities were consistently correlated to widespread surface cortical EEG activities and symptoms in all patients and all types of generalized seizures; i.e., fast spike discharges at CM correlated at onset of tonic and tonic-clonic generalized seizures; slow (1-2 Hz) spike-wave complex discharges at CM correlated for atypical absence seizures; slow polyspike-wave complex discharges correlated for myoclonic seizures; and spike bursts and suppression patterns correlated for combined tonic-atonic-myoclonic seizures. Ictal EEG activities occurred simultaneously at right and left CM and surface at onset of all seizure types, with the exception of myoclonic seizures where CM complete discharges and individual spike-wave complexes significantly lead those of the surface. Brief tonic-atonic spasms clinically undistinguishable from "real" epileptic seizures showed no EEG counterparts at CM and surface. Interictal CM spike-wave complete discharges and individual spike-wave complexes showed variable amplitude-temporal patterns. Amplitude emphasis on CM and frontopolar regions was observed in most of complete discharges, however, and phase shifts between CM and frontopolar regions were observed in individual spike-wave complexes.


Assuntos
Eletroencefalografia , Epilepsia/fisiopatologia , Núcleos Talâmicos/fisiopatologia , Adulto , Fatores Etários , Encéfalo/fisiopatologia , Córtex Cerebral/fisiopatologia , Criança , Pré-Escolar , Eletrodos Implantados , Eletroencefalografia/métodos , Epilepsias Mioclônicas/fisiopatologia , Lateralidade Funcional/fisiologia , Humanos , Masculino , Vias Neurais/fisiopatologia , Formação Reticular/fisiopatologia , Sono/fisiologia , Síndrome , Telemetria , Tálamo/fisiopatologia , Vigília/fisiologia
9.
Int J Neurosci ; 54(3-4): 325-37, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2125031

RESUMO

Continuous all night recordings of epileptiform EEG activities from right frontal scalp and thalamic Centromedian regions and EMG activities from left deltoid muscular region were performed on a child with intractable epilepsia partialis continua, with depth stimulating-recording electrodes used for neuroaugmentive seizure control. In addition, "normal" and "mature" sleep indicators in the same child were simultaneously recorded according to the International Procedures. During wakefulness (W), type B seizures consisted of isolated, high amplitude, negative-positive EEG sharp waves recorded from the right Centromedian region (RCM sharp) correlated with isolated bursts of high amplitude EMG potentials recorded from the left deltoid muscle (LEMG jerks). Type C seizures consisted of clusters of repetitive RCM sharp and LEMG jerks, where individual EEG-EMG activities showed poor correlations. Number and amplitude of type B RCM sharp and LEMG jerks significantly decreased when patient directly shifted from W to slow wave sleep I and II (SWSI and II). Number and amplitude of RCM sharp increased while those of LEMG jerks decreased directly from SWS I and II to slow wave sleep III (SWS III); all forms of EEG-EMG epileptiform type B activities significantly decreased directly or indirectly from W and SWS to paradoxical sleep (PS). Scalp EEG spikes from right frontal and central regions showed almost parallel changes to those of RCM sharp, except during SWS II, when amplitude increased in the former and decreased in the later. Occurrence of type C seizures only decreased during PS and duration decreased directly from SWS I to II and indirectly from SWS I to SWS II and PS; and from W to SWS II and III and PS.


Assuntos
Eletroencefalografia , Eletromiografia , Epilepsias Parciais/fisiopatologia , Sono/fisiologia , Vigília/fisiologia , Pré-Escolar , Epilepsias Mioclônicas/fisiopatologia , Epilepsias Parciais/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética
10.
Int J Neurosci ; 43(1-2): 123-31, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3215728

RESUMO

We had previously observed that in groups of children with low socioeconomic and cultural level the EEG spectral parameters did not correlate with age due to the great variance in the distribution of such EEG parameters. In this paper we have made several statistical analyses in order to look for other factors that may explain the great variance observed. EEG during rest was recorded in 14 monopolar leads from 119 children. After FFT the following measures were calculated: absolute power, relative power, dominant frequency, coherence and left power/right power ratio for the delta, theta, alpha and beta bands in each derivation. For each measure, in each derivation, ANOVA analyses were performed taking age as covariable and sex, presence or absence of antecedents of risk factors and of learning disorders (LD) as independent variables. Age had its main effect on absolute power in the different bands and in the dominant frequency in the alpha band. Sex affected absolute and relative power in the alpha band. Risk factors per se had no effect. Presence of LD showed its main effect on absolute power. Many interactions between risk and LD and sex and LD were observed. Other analyses, such as MANCOVA, corroborated these results: significant differences between girls and boys, significant differences between children with and without LD and no differences between children with and without antecedents of risk factors.


Assuntos
Eletroencefalografia , Deficiências da Aprendizagem/fisiopatologia , Adolescente , Fatores Etários , Criança , Feminino , Humanos , Masculino , México , Fatores de Risco , Fatores Sexuais , Fatores Socioeconômicos
11.
Int J Neurosci ; 41(1-2): 103-13, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3410648

RESUMO

It has been shown that EEG maturation can be described in terms of regression equations on age of broad band EEG frequency parameters. In the present paper six groups of children with different economic and psychosocial characteristics of three countries were studied. Regression equations on age of the EEG relative power (expressed in percentages of the total EEG activity) in the delta, theta, alpha and beta bands in 8 bipolar derivations were computed in each group of children and the slopes compared with those previously published by John et al. (1980). Those children who grew up with adequate nutritional, sanitary and cultural environmental conditions showed the same slopes as U.S. and Swedish children selected with strict criteria of normality. Children nourished in poor socioeconomic and sanitary environments and who frequently had pathological personal antecedents with risk factors associated with brain damage showed either a slow maturation of the EEG characterized by smaller slopes of theta relative power or a great variance of EEG parameters and no relation of these parameters to age.


Assuntos
Desenvolvimento Infantil , Eletroencefalografia , Carência Psicossocial , Fatores Socioeconômicos , Criança , Cuba , Feminino , Humanos , Masculino , México , Análise de Regressão , Venezuela
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