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1.
J Appl Anim Welf Sci ; : 1-16, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39206681

RESUMO

Research on equine-assisted therapy (EAT) has primarily been centered on human health. Relatively few studies have addressed the impact of EAT on horses. This study sought to monitor four experienced therapy horses' cardiovascular and glucocorticoid activity over the course of standardized EAT sessions designed to support women with intellectual disability. In the control condition, horses completed the EAT protocol solely with the therapist, thereby resembling a training session. Descriptive data analysis revealed higher levels of heart rate during an experimental EAT session and increased salivary cortisol when horses were navigated by the client through an obstacle course during the "challenge" phase of the protocol, pointing at a greater physical demand due to the recipient on horseback. Given the parasympathetic activity and overall heart rate variability across experimental EAT sessions and the cortisol recovery after the sessions, the findings do not give rise to any acute animal welfare concerns. For a more holistic interpretation of the present research results, further investigation into the horse perception of EAT, based on a bigger sample size and additional markers of welfare, is needed.

3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 1777-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26736623

RESUMO

One of the major drawbacks in mobile EEG Brain Computer Interfaces (BCI) is the need for subject specific training data to train a classifier. By removing the need for supervised classification and calibration phase, new users could start immediate interaction with a BCI. We propose a solution to exploit the structural difference by means of canonical polyadic decomposition (CPD) for three-class auditory oddball data without the need for subject-specific information. We achieve this by adding average event-related-potential (ERP) templates to the CPD model. This constitutes a novel similarity measure between single-trial pairs and known-templates, which results in a fast and interpretable classifier. These results have similar accuracy to those of the supervised and cross-validated stepwise LDA approach but without the need for having subject-dependent data. Therefore the described CPD method has a significant practical advantage over the traditional and widely used approach.


Assuntos
Eletroencefalografia/métodos , Potenciais Evocados P300 , Potenciais Evocados Auditivos , Interfaces Cérebro-Computador , Calibragem , Humanos , Modelos Teóricos , Reprodutibilidade dos Testes , Adulto Jovem
4.
Heredity (Edinb) ; 113(1): 42-51, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24619180

RESUMO

Determining the mechanisms responsible for the distribution of genetic diversity in natural populations has occupied a central role in molecular evolution. Our study was motivated by the unprecedented observation that a widespread Eurasian flycatcher, Ficedula albicilla, exhibited no variation at the mitochondrial DNA (mtDNA) ND2 gene in 75 individuals sampled over a 5000-km distance. In contrast, its sister species, F. parva, had low but considerably higher levels of mtDNA variation. We assessed whether natural selection or demographic factors could explain the absence of mtDNA variation in F. albicilla. Eighteen nuclear genes were sequenced to estimate the two species' phylogeographic histories, and for comparison to the mtDNA data. Multilocus coalescence analyses suggested that F. albicilla experienced a population expansion perhaps following a population bottleneck. Simulations based on this demographic history, however, did not replicate the extremely low level of mtDNA variation. Historical range changes based on ecological niche models also failed to explain the observed mtDNA patterns. Neutrality tests (DHEW and ML-HKA) suggested a non-neutral pattern in the mtDNA of F. albicilla. We found a transmembrane-skewed distribution of nonsynonymous substitutions between the two species, three of which caused functional change; the results implied that positive selection could have targeted mtDNA. Several lines of evidence support selection rather than demographic history as the main force influencing the patterns of mtDNA variation. Despite the influence of natural selection, many of the phylogeographic inferences derived from mtDNA were robust, including species limits and a high level of gene flow among populations within species.


Assuntos
DNA Mitocondrial/genética , Evolução Molecular , Variação Genética/genética , Genética Populacional , Seleção Genética/genética , Aves Canoras/genética , Distribuição Animal , Animais , Sequência de Bases , Simulação por Computador , Efeito Fundador , Fluxo Gênico/genética , Modelos Genéticos , Dados de Sequência Molecular , NADH Desidrogenase/genética , Filogeografia , Densidade Demográfica , Análise de Sequência de DNA
5.
Heredity (Edinb) ; 109(1): 29-33, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22354113

RESUMO

In this study, we take advantage of a natural experiment--a 2004 mass die-off of the Common Murre in Alaska to determine whether closely related mtDNA haplotypes differ in their probability of being eliminated during such a short term but a marked event removing hundreds of thousands of individuals. We sequenced complete mtDNA ND2 gene (1041 bp) for 168 Common Murres sampled from seven breeding colonies across Alaska before the 2004 die-off and 127 dead murres washed ashore during the die-off. We found little mtDNA variation and lack of geographical structuring among the seven Common Murre breeding colonies in Alaska. A comparison of the single-dominant mtDNA haplotype's frequency between live murres sampled on breeding colonies before the die-off (73.2%; 95% confidence interval 66.3-79.9%) and dead murres sampled during the die-off (59.1%; 95% confidence interval 50.4-67.4%; Fisher's exact P=0.01) showed that carriers of the dominant haplotype were significantly less likely to die than carriers of other haplotypes. At the same time, the ratio of non-synonymous to synonymous substitutions did not differ between live (10:35) and dead birds (18:34; Fisher's exact P=0.26), indicating that non-synonymous substitutions were as likely to be eliminated as synonymous substitutions. These results are consistent with the possibility of positive selection on the dominant mtDNA haplotype during the die-off.


Assuntos
Aves/genética , DNA Mitocondrial/genética , Haplótipos , Alaska , Animais , Variação Genética , Geografia , Filogenia
6.
Clin Pharmacol Ther ; 91(2): 257-63, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22190063

RESUMO

Variants in ABCB1 and CYP2C19 have been identified as predictors of cardiac events during clopidogrel therapy initiated after myocardial infarction (MI) or percutaneous coronary intervention (PCI). In addition, PON1 has recently been associated with stent thrombosis. The reported effects of these variants have not yet been replicated in a real-world setting. We used BioVU, the Vanderbilt DNA repository linked to de-identified electronic health records (EHRs), to find data on patients who were on clopidogrel treatment after an MI and/or a PCI; among these, we identified those who had experienced one or more recurrent cardiac events while on treatment (cases, n = 225) and those who had not experienced any cardiac event while on treatment (controls, n = 468). We found that CYP2C19*2 (hazard ratio (HR) 1.54, 95% confidence interval (CI) 1.16-2.06, P = 0.003) and ABCB1 (HR 1.28, 95% CI 1.04-1.57, P = 0.018), but not PON1 (HR 0.91, 95% CI 0.73-1.12, P = 0.370), were associated with recurrent events. In this population, genetic signals for clopidogrel resistance in ABCB1 and CYP2C19 were replicated, supporting the use of EHRs for pharmacogenomic studies. Our data do not show an association between PON1 and recurrent cardiovascular events.


Assuntos
Bases de Dados de Ácidos Nucleicos , Registros Eletrônicos de Saúde , Infarto do Miocárdio/tratamento farmacológico , Farmacogenética/métodos , Inibidores da Agregação Plaquetária/uso terapêutico , Trombose/tratamento farmacológico , Ticlopidina/análogos & derivados , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Idoso , Hidrocarboneto de Aril Hidroxilases/genética , Arildialquilfosfatase/genética , Clopidogrel , Citocromo P-450 CYP2C19 , Feminino , Genótipo , Humanos , Masculino , Polimorfismo Genético , Stents , Ticlopidina/uso terapêutico , Resultado do Tratamento
7.
Vet Parasitol ; 161(3-4): 330-4, 2009 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-19285809

RESUMO

The white-tailed deer (Odocoileus virginianus) is considered one of the most important wildlife reservoirs of Neospora caninum and Toxoplasma gondii in the US. Sera from white-tailed deer from Minnesota and Iowa were tested for antibodies to N. caninum by four serologic tests including the indirect fluorescent antibody (IFA) test (cut-off 1:25), Neospora caninum agglutination test (cut-off 1:25), an enzyme-linked immunoabsorbent assay, and Western blot (WB). Sera were also tested for antibodies to T. gondii using the modified agglutination test (cut-off 1:25). Of 62 adult deer from Minnesota antibodies to T. gondii were found in 20 (32.2%), N. caninum in 44 (71%), with dual infections in 18 deer. Of 170 (73 fawns, 9 yearlings, 88 adults) deer from Iowa, T. gondii antibodies were present in 91 (53.5%) with 37.0, 55.6 and 67.0% seropositivity in fawns, yearlings, and adults, respectively. Antibodies to N. caninum were found in 150 of 170 (88.2%) by any of the 3 tests (99 by Western blots, 135 by ELISA, 106 by IFA, and 118 by NAT). Dual infections with T. gondii and N. caninum were detected in 47 deer. Very high (84.9%) seropositivity of N. caninum in fawns suggests high rate of congenital transmission of the parasite. Seropositivity in each test at different titers is discussed.


Assuntos
Coccidiose/veterinária , Cervos , Neospora/imunologia , Toxoplasma/imunologia , Toxoplasmose Animal/imunologia , Animais , Coccidiose/epidemiologia , Coccidiose/imunologia , Coccidiose/parasitologia , Feminino , Iowa/epidemiologia , Minnesota/epidemiologia , Estudos Soroepidemiológicos , Testes Sorológicos/veterinária , Toxoplasmose Animal/epidemiologia
8.
Parasitol Res ; 92(5): 436-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15115001

RESUMO

During a study on the mortality of California sea lion (Zalophus californianus) pups born on San Miguel Island, California in 2002, two adult female hookworms (Uncinaria spp) were found penetrating the serosal surface of the intestinal wall and protruding into the peritoneal cavity of one pup. Documentation and a description of this unexpected finding and associated lesions are presented here. Also, adult hookworms were found in the peritoneal fluid of two other dead Z. californianus pups.


Assuntos
Ancylostomatoidea/patogenicidade , Infecções por Uncinaria/veterinária , Intestino Delgado/parasitologia , Leões-Marinhos/parasitologia , Animais , Líquido Ascítico/parasitologia , Intestino Delgado/patologia , Cavidade Peritoneal/parasitologia , Cavidade Peritoneal/patologia
9.
Rev. chil. enferm. respir ; 19(2): 118-122, abr.-jun. 2003. ilus
Artigo em Espanhol | LILACS | ID: lil-362672

RESUMO

El traumatismo torácico es una entidad patológica emergente, relacionada con accidentes automovilísticos. La lesión más frecuente es la fractura costal. Dependiendo de su gravedad, éste puede provocar tórax volante, contusión cardíaca, lesiones vasculares u otras alteraciones. La ruptura bronquial se observa ocasionalmente en traumatismos torácicos cerrados, y por lo general tiene lugar en el tronco del árbol tráqueo-bronquial. Su diagnóstico y manejo inicial representan un problema mayor. Los signos clásicos son la persistencia de neumotórax y flujo masivo de aire a través del drenaje torácico: sin embargo también hay casos que no son típicos. Es difícil determinar el momento correcto para iniciar la ventilación con presión positiva, la que puede aumentar gravemente el flujo de aire a través de la ruptura bronquial y acentuar el neumotoráx a tensión. Presentamos el caso de un hombre de 25 años con un traumatismo torácico cerrado, causado por un accidente de automóvil, en quien la broncoscopía demostró una fractura del bronquio lobar medio. Comprobamos en este paciente, que la fibrobroncoscopía es el procedimiento más útil tanto en el diagnóstico, como en el tratamiento inicial y en el seguimiento post operatorio de su fractura bronquial.


Assuntos
Humanos , Masculino , Adulto , Traumatismos Torácicos/complicações , Traumatismos Torácicos/diagnóstico , Traumatismos Torácicos/patologia , Acidentes de Trânsito , Broncoscopia , Fraturas Ósseas , Tomografia
10.
Vet Pathol ; 39(5): 546-56, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12243464

RESUMO

Serial sections of brain and palatine tonsil were examined by immunohistochemical staining (IHC) using monoclonal antibody F89/160.1.5 for detecting protease-resistant prion protein (PrP(res)) in 35 hunter-killed mule deer (Odocoileus hemionus) with chronic wasting disease. Serial sections of brain were stained with hematoxylin and eosin and examined for spongiform encephalopathy (SE). Clinical signs of disease were not observed in any of these deer. On the basis of the location and abundance of IHC and the location and severity of SE, deer were placed into four categories. Category 1 (n = 8) was characterized by IHC in the palatine tonsil with no evidence of IHC or SE in the brain. Category 2 (n = 13) was characterized by IHC in the palatine tonsil and IHC with or without SE in the dorsal motor nucleus of the vagus nerve (DMNV). Category 3 (n = 2) was characterized by IHC in the palatine tonsil, IHC with SE in the myelencephalon, and IHC without SE in the hypothalamus. Category 4 (n = 12) was characterized by IHC in the palatine tonsil and IHC with SE throughout the brain. Category I may represent early lymphoid tissue localization of PrP(res). The DMNV appears to be the most consistent single neuroanatomic site of detectable PrP(res). Categories 2-4 may represent a progression of spread of PrP(res) and SE throughout the brain. IHC in tonsil and brain and SE in brain were not detected in 208 control deer.


Assuntos
Encéfalo/metabolismo , Cervos/metabolismo , Tonsila Palatina/metabolismo , Príons/metabolismo , Doença de Emaciação Crônica/metabolismo , Animais , Síndrome de Creutzfeldt-Jakob/metabolismo , Síndrome de Creutzfeldt-Jakob/patologia , Imuno-Histoquímica/veterinária , Príons/isolamento & purificação , Doença de Emaciação Crônica/patologia
11.
Vet Pathol ; 39(1): 110-9, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12102202

RESUMO

In this investigation, the nature and distribution of histologic lesions and immunohistochemical staining (IHC) of a proteinase-resistant prion protein were compared in free-ranging mule deer (Odocoileus hemionus) dying of a naturally occurring spongiform encephalopathy (SE) and captive mule deer dying of chronic wasting disease (CWD). Sixteen free-ranging deer with SE, 12 free-ranging deer without SE, and 10 captive deer with CWD were examined at necropsy. Tissue sections were stained with hematoxylin and eosin, and duplicate sections were stained with a monoclonal antibody (F89/160.1.5). Histological lesions in the free-ranging deer with SE and captive deer with CWD were found throughout the brain and spinal cord but were especially prominent in the myelencephalon, diencephalon, and rhinencephalon. The lesions were characterized by spongiform degeneration of gray matter neuropil, intracytoplasmic vacuolation and degeneration of neurons, and astrocytosis. IHC was found throughout the brain and retina of deer with SE and CWD. Positive IHC was found in lymphoid tissue of deer with SE and CWD. Histologic lesions and IHC were not found in multiple sections of integument, digestive, respiratory, cardiovascular, endocrine, musculoskeletal, and urogenital systems of deer with SE or CWD. Comparison of histologic lesions and IHC in tissues of free-ranging deer with those of captive deer provides strong evidence that these two diseases are indistinguishable morphologically.


Assuntos
Encéfalo/patologia , Cervos , Doenças Priônicas/veterinária , Príons/análise , Medula Espinal/patologia , Animais , Animais Domésticos , Animais Selvagens , Colorado/epidemiologia , Doenças Priônicas/epidemiologia , Doenças Priônicas/patologia , Estudos Retrospectivos
12.
J Vet Diagn Invest ; 14(1): 3-7, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12680636

RESUMO

A new monoclonal antibody (MAb), F99/97.6.1, that has been used to demonstrate scrapie-associated prion protein PrP(Sc) in brain and lymphoid tissues of domestic sheep with scrapie was used in an immunohistochemistry assay for diagnosis of chronic wasting disease (CWD) in mule deer (Odocoileus hemionus). The MAb F99/97.6.1 immunohistochemistry assay was evaluated in brain and tonsil tissue from 100 mule deer that had spongiform encephalopathy compatible with CWD and from 1,050 mule deer outside the CWD-endemic area. This MAb demonstrated abnormal protease-resistant prion protein (PrP(res)) in brains of all of the 100 mule deer and in 99 of the 100 tonsil samples. No immunostaining was seen in samples collected from deer outside the endemic area. MAb F99/97.6.1 demonstrated excellent properties for detection of PrP(res) in fresh, frozen, or mildly to moderately autolytic samples of brain and tonsil. This immunohistochemistry assay is a sensitive, specific, readily standardized diagnostic test for CWD in deer.


Assuntos
Anticorpos Monoclonais/imunologia , Encéfalo/imunologia , Cervos/imunologia , Tonsila Palatina/imunologia , Proteínas PrPSc/imunologia , Doença de Emaciação Crônica/diagnóstico , Doença de Emaciação Crônica/imunologia , Animais , Encéfalo/patologia , Feminino , Imuno-Histoquímica , Masculino , Tonsila Palatina/patologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Doença de Emaciação Crônica/patologia
13.
FEMS Microbiol Ecol ; 36(2-3): 113-121, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11451515

RESUMO

One hundred and six isolates of the genus Bifidobacterium, isolated from different environments (mainly gastrointestinal), were identified and classified taxonomically to species level by amplified ribosomal DNA restriction analysis. Two restriction endonucleases (Sau3AI and BamHI) were chosen for aligning the 16S rRNA sequences of 16 bifidobacterial species retrieved from various databases, to obtain species-specific restriction patterns. A rapid and accurate identification scheme was obtained by comparing the resulting 16S rDNA digestion profiles of 16 Bifidobacterium type-strains and 90 strains of various origins. All of the investigated strains were previously confirmed at the species level as belonging to the genus Bifidobacterium by fluorescence in-situ hybridisation and by polymerase chain reaction amplification with genus- and species-specific primers. The present work demonstrates that species-specific detection of Bifidobacterium adolescentis, Bifidobacterium animalis, Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium catenulatum, Bifidobacterium coryneforme, Bifidobacterium cuniculi, Bifidobacterium dentium, Bifidobacterium infantis, Bifidobacterium lactis, Bifidobacterium longum, Bifidobacterium suis, Bifidobacterium magnum, Bifidobacterium pseudolongum, Bifidobacterium pseudocatenulatum and Bifidobacterium pullorum present in different micro-ecological environments (e.g. gastrointestinal tract) can be accomplished in a reliable, rapid and accurate manner, circumventing the recognised deficiencies of traditional identification techniques.

14.
Appl Environ Microbiol ; 67(6): 2760-5, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11375192

RESUMO

The species Bifidobacterium lactis, with its main representative strain Bb12 (DSM 10140), is a yoghurt isolate used as a probiotic strain and is commercially applied in different types of yoghurts and infant formulas. In order to ensure the genetic identity and safety of this bacterial isolate, species- and strain-specific molecular tools for genetic fingerprinting must be available to identify isolated bifidobacteria or lactic acid bacteria from, e.g., various clinical environments of relevance in medical microbiology. Two opposing rRNA gene-targeted primers have been developed for specific detection of this microorganism by PCR. The specificity of this approach was evaluated and verified with DNA samples isolated from single and mixed cultures of bifidobacteria and lactobacilli (48 isolates, including the type strains of 29 Bifidobacterium and 9 Lactobacillus species). Furthermore, we performed a Multiplex-PCR using oligonucleotide primers targeting a specific region of the 16S rRNA gene for the genus Bifidobacterium and a conserved eubacterial 16S rDNA sequence. The specificity and sensitivity of this detection with a pure culture of B. lactis were, respectively, 100 bacteria/ml after 25 cycles of PCR and 1 to 10 bacteria/ml after a 50-cycle nested-PCR approach.


Assuntos
Bifidobacterium/isolamento & purificação , Microbiologia Ambiental , Reação em Cadeia da Polimerase/métodos , Técnicas de Tipagem Bacteriana , Bifidobacterium/classificação , Bifidobacterium/genética , Primers do DNA , DNA Ribossômico/genética , DNA Ribossômico/isolamento & purificação , Laticínios/microbiologia , Microbiologia de Alimentos , Humanos , Lactente , Alimentos Infantis/microbiologia , Lactobacillus/genética , Probióticos , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/isolamento & purificação , Sensibilidade e Especificidade , Especificidade da Espécie
15.
Chemphyschem ; 2(6): 377-83, 2001 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-23686959

RESUMO

The energy profile for rotation around the central Si-Si bonds of the tetrasilanes SiMe3SiX2SiX2SiMe3 (X=H, F, Cl, Br and I) were examined by ab initio calculations and temperature-dependent Raman spectroscopy. Ethanelike intrinsic barriers to rotation were found for X=H, Cl, Br and I. MP2 calculations predict for SiMe3SiF2SiF2SiMe3 the existence of a gauche minimum with backbone dihedral angle ω≈64° and a twisted minimum with ω≈115°, as shown in the picture (solid line=HF, dashed line=MP2). The curious 115° local minium can be accounted for by a unique intrinsic barrier to rotation superimposed by electrostatic interactions involving strongly polar SiF bonds.

16.
Rev. Hosp. Clin. Univ. Chile ; 12(3): 209-216, 2001. tab
Artigo em Espanhol | LILACS | ID: lil-302623

RESUMO

Se reportan 10 pacientes con miastenia gravis a los cuales se les resecó el timo con técnica videotoracoscópica en este centro universitario. Desde mayo de 1997 a agosto de 2000, 10 pacientes que padecían de miastenia gravis, 7 mujeres y 3 hombres, con una edad promedio de 33 años y un rango de edad de 17 a 52 años, fueron sometidos a timectomía utilizando la técnica de VATS. El tiempo promedio de evolución de la enfermedad fue de aproximadamente 15 meses con un rango de 2 a 26 meses. La técnica quirúrgica incluyó una vía de abordaje por el lado derecho en 9 pacientes y bilateral en 1. El tiempo promedio de operación fue de aproximadamente 3 horas, con un rango de 1 a 4 horas. No hubo mortalidad operatoria y ningún paciente presentó complicaciones intra o postoperatorias. Asimismo no hubo casos que requirieran ventilación mecánica. El tiempo promedio de días postoperatorio fue de aproximadamente 2 días con un rango de 1 a 5 días. El análisis de este grupo nos muestra que los resultados son buenos en dos casos, con mejoría parcial en 4 casos. El tiempo de control aún breve nos sugiere que podrían mejorar. Así mismo el tiempo de evolución parece aconsejar indicaciones quirúrgicas más precoces. Se concluye por los resultados obtenidos que la timectomía por VATS es apropiado para el tratamiento de la miastenia gravis, lo cual concuerda con las informaciones obtenidas de la literatura mundial


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Pessoa de Meia-Idade , Cirurgia Vídeoassistida/métodos , Miastenia Gravis , Toracoscopia , Timectomia , Complicações Intraoperatórias , Resultado do Tratamento
17.
Int J Food Microbiol ; 55(1-3): 41-5, 2000 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-10791715

RESUMO

The presence of the dnaK heat shock gene could be demonstrated for B. longum NCC481, B. longum NCC490, B. longum NCC585, B. adolescentis NCC251, and B. breve NCC298. Induction of dnaK on the transcriptional level was shown for NCC251 and NCC481 by increasing temperatures. NCC251 showed an additional chaperone-induction after salt or bile-salt treatment. In both strains preconditioning with bile-salts protected against otherwise lethal concentrations thereof. NCC251 when subjected to a heat stress was able to survive an otherwise lethal temperature (55 degrees C). Cross-protection was demonstrated for NCC251 since salt pretreatment resulted in increased tolerance after freeze-thawing cycles or lethal heat stress.


Assuntos
Bifidobacterium/fisiologia , Proteínas de Escherichia coli , Proteínas de Choque Térmico HSP70/genética , Bifidobacterium/genética , RNA Mensageiro/análise , Cloreto de Sódio/farmacologia
18.
J Appl Microbiol ; 88(4): 695-703, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10792529

RESUMO

A completely chemically-defined growth medium, containing guanine, thymine, cytidine, 2'-deoxyadenosine and 2'-deoxyuridine as DNA precursors, was developed for Lactobacillus johnsonii, on the basis of statistically designed techniques suitable for other lactobacilli. Particular focus was given to the nucleotide composition of different defined media, and to the specific nucleotide requirements of Lact. johnsonii. Most of the lactobacilli tested grew in a medium containing five free bases, four ribonucleosides or five deoxyribonucleosides. Adenine and guanine were replaceable by inosine. The requirement for thymine and cytosine was satisfied with uracil. The presence of inosine and uracil was identified as being essential for the growth of different Lactobacillus species, displaying their inability to synthesize purines and pyrimidines de novo. Defined recipes with different nucleotide composition were used to investigate iron requirements of lactobacilli. Only marginal differences in growth were observed in iron-depleted media supplemented with five free bases, four ribonucleosides or five deoxyribonucleosides; iron depletion had a greater effect on growth when inosine and uracil were supplied as the only nucleotide sources. The results suggest that iron plays a role in the pyrimidine and purine metabolism of lactobacilli. Lactobacillus spp., particularly Lact. johnsonii, require iron under particular environmental conditions with limited or specific nucleotide sources.


Assuntos
Ferro/metabolismo , Lactobacillus/crescimento & desenvolvimento , Meios de Cultura , Nucleotídeos
19.
Alcohol Clin Exp Res ; 24(3): 265-77, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10776662

RESUMO

BACKGROUND: Hormonal responses to alcohol have been reported to differ in subjects with and without a family history of alcoholism which suggests that alcohol-induced hormonal changes might be used to identify individuals who are at elevated genetic risk for developing alcoholism. However, before a biological response can be used as a marker of genetic risk for disease, it must first be demonstrated that the response is, in fact, heritable. The present study was designed to determine whether hormonal responses to alcohol are heritable. METHODS: The adrenocorticotropic hormone (ACTH), beta-endorphin (beta-E), cortisol (CORT), and prolactin (PRL) responses to alcohol were examined in male and female identical (monozygotic or MZ) and fraternal (dizygotic or DZ) twin pairs. Male subjects consumed 0.35 g ethanol/kg body weight (BW) and females consumed 0.325 g ethanol/kg BW in each of two alcohol drinking sessions administered 1 hr apart (total dose of 0.7 g/kg BW in males and 0.65 g/kg BW in females). Plasma hormone content was analyzed in samples collected before (resting conditions) and at 15, 60, 75, 120, 180, and 240 min after onset of drinking. Hormonal responses to alcohol were examined with twin analyses using the TWINAN90 program. A separate analysis was performed for each of the four hormones. A subset of subjects from each zygosity was seen on two separate occasions to establish retest reliability. Heritability of hormonal responses to alcohol was estimated using the intraclass correlation approach before and after removing the contribution of covariates that have the potential of influencing the plasma levels of these hormones. RESULTS: Resting plasma levels of all four hormones were within the expected range, and the beta-E, ACTH, and PRL responses to the alcohol challenge evidenced good test-retest reliability. Of the four hormones examined, the only one that showed significant heritability after alcohol drinking was beta-E. Heritability estimates were not altered for any of the four hormones after removal of the variance contributed by covariates, such as gender and age. CONCLUSIONS: Taken together with other recent findings, the results suggest that the beta-E response to alcohol may represent a new biomarker that can be used to identify individuals who are at elevated genetic risk for developing alcoholism.


Assuntos
Alcoolismo/genética , beta-Endorfina/genética , Adulto , Alcoolismo/sangue , Biomarcadores/sangue , Testes Respiratórios , Depressores do Sistema Nervoso Central/sangue , Depressores do Sistema Nervoso Central/farmacologia , Etanol/sangue , Etanol/farmacologia , Feminino , Predisposição Genética para Doença , Humanos , Masculino , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , beta-Endorfina/sangue , beta-Endorfina/efeitos dos fármacos
20.
J Biotechnol ; 78(3): 251-8, 2000 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-10751686

RESUMO

The production of foods for an increasingly informed and selective consumer requires the coordinated activities of the various branches of the food chain in order to provide convenient, wholesome, tasty, safe and affordable foods. Also, the size and complexity of the food sector ensures that no single player can control a single process from seed production, through farming and processing to a final product marketed in a retail outlet. Furthermore, the scientific advances in genome research and their exploitation via biotechnology is leading to a technology driven revolution that will have advantages for the consumer and food industry alike. The segment of food processing aids, namely industrial enzymes which have been enhanced by the use of biotechnology, has proven invaluable in the production of enzymes with greater purity and flexibility while ensuring a sustainable and cheap supply. Such enzymes produced in safe GRAS microorganisms are available today and are being used in the production of foods. A second rapidly evolving segment that is already having an impact on our foods may be found in the new genetically modified crops. While the most notorious examples today were developed by the seed companies for the agro-industry directed at the farming sector for cost saving production of the main agronomical products like soya and maize, its benefits are also being seen in the reduced use of herbicides and pesticides which will have long term benefits for the environment. Technology-driven advances for the food processing industry and the consumer are being developed and may be divided into two separate sectors that will be presented in greater detail: 1. The application of genome research and biotechnology to the breeding and development of improved plants. This may be as an aid for the cataloging of industrially important plant varieties, the rapid identification of key quality traits for enhanced classical breeding programs, or the genetic modification of important plants for improved processing properties or health characteristics. 2. The development of advanced microorganisms for food fermentations with improved flavor production, health or technological characteristics. Both yeasts and bacteria have been developed that fulfill these requirements, but are as yet not used in the production of foods.


Assuntos
Indústria Alimentícia , Genoma , Biologia Molecular , Bacteriófagos/genética , Biotecnologia , Cacau/genética , Microbiologia de Alimentos , Genoma de Planta , Lactobacillus/genética , Probióticos , Streptococcus/virologia
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