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1.
Mar Pollut Bull ; 119(2): 68-73, 2017 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-28431744

RESUMO

Marine debris such as plastic fragments and fishing gears are accumulating in the ocean at alarming rates. This study assesses the incidence of debris in the gastrointestinal tracts of seabirds feeding at different depths and found stranded along the Brazilian coast in the period 2010-2013. More than half (55%) of the species analysed, corresponding to 16% of the total number of individuals, presented plastic particles in their gastrointestinal tracts. The incidence of debris was higher in birds feeding predominantly at intermediate (3-6m) and deep (20-100m) waters than those feeding at surface (<2m). These results suggest that studying the presence of debris in organisms mainly feeding at the ocean surface provides a limited view about the risks that this form of pollution has on marine life and highlight the ubiquitous and three-dimensional distribution of plastic in the oceans.


Assuntos
Aves , Monitoramento Ambiental , Plásticos/farmacocinética , Animais , Brasil , Dieta , Incidência , Oceanos e Mares , Água
2.
Clin Neurophysiol ; 122(4): 719-24, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21051281

RESUMO

OBJECTIVE: The limited evidence and inconsistency of purposeful behaviors in patients in a minimally conscious state (MCS) asks for objective electrophysiological marker of the level of consciousness. Here, a comparison between event-related potentials (ERPs) was investigated using different level of stimulus complexity. METHODS: The patients in vegetative state were 11 and the MCS patients were 6 [corrected]. Three oddball paradigms with different level of complexity were applied: sine tones, the subject's own name versus sine tones and other first names. Latencies and amplitudes of N1 and P3 waves were compared. RESULTS: Cortical responses were found in all MCS patients, and in 6 of 11 patients in VS. Healthy controls and MCS patients showed a progressive increase of P3 latency in relation to the level of stimulus complexity. No modulation of P3 latency was observed in the vegetative patients. CONCLUSIONS: These results suggest that the modulation of P3 latency related to stimulus complexity may represent an objective index of higher-order processing integration that predicts the recovery of consciousness from VS to MCS when clinical manifestations are inconsistent. SIGNIFICANCE: Modulation of P3 latency related to stimulus complexity could provide valuable information about the cognitive capabilities of unresponsive patients.


Assuntos
Dano Encefálico Crônico/fisiopatologia , Potenciais Evocados/fisiologia , Estimulação Acústica , Adulto , Análise de Variância , Encéfalo/fisiologia , Dano Encefálico Crônico/diagnóstico , Córtex Cerebral/fisiopatologia , Estado de Consciência/fisiologia , Diagnóstico Diferencial , Avaliação da Deficiência , Eletroencefalografia , Feminino , Humanos , Masculino , Estado Vegetativo Persistente/diagnóstico , Estado Vegetativo Persistente/fisiopatologia , Estado Vegetativo Persistente/psicologia , Reprodutibilidade dos Testes
3.
Int J Food Microbiol ; 130(3): 238-44, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19237217

RESUMO

Eighty four isolates of Brettanomyces bruxellensis, were collected during fermentation of Sangiovese grapes in several Tuscan wineries and characterized by restriction analysis of 5.8S-ITS and species-specific PCR. The isolates were subsequently analysed, at strain level, by the combined use of the RAPD-PCR assay with primer OPA-02 and the mtDNA restriction analysis with the HinfI endonuclease. This approach showed a high degree of polymorphism and allowed to identify seven haplotypes, one of them being the most represented and widely distributed (72 isolates, 85.7%). Physiological traits of the yeasts were investigated under a wine model condition. Haplotypes clustered into two groups according to their growth rates and kinetics of production of 4-ethylphenol and 4-ethylguaiacol. Hexylamine was the biogenic amine most produced (up to 3.92 mg l(-1)), followed by putrescine and phenylethylamine. Formation of octapamine was detected by some haplotypes, for the first time.


Assuntos
Brettanomyces/genética , Brettanomyces/fisiologia , Vinho/classificação , Vinho/microbiologia , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , DNA Intergênico , Variação Genética , Itália , Reação em Cadeia da Polimerase/métodos , Especificidade da Espécie
4.
Artigo em Inglês | MEDLINE | ID: mdl-17065052

RESUMO

The pyrimidine catabolic pathway is of crucial importance in cancer patients because it is involved in degradation of several chemotherapeutic drugs, such as 5-fluorouracil; it also is important in plants, unicellular eukaryotes, and bacteria for the degradation of pyrimidine-based biocides/antibiotics. During the last decade we have developed a yeast species, Saccharomyces kluyveri, as a model and tool to study the genes and enzymes of the pyrimidine catabolic pathway. In this report, we studied degradation of uracil and its putative degradation products in 38 yeasts and showed that this pathway was present in the ancient yeasts but was lost approximately 100 million years ago in the S. cerevisiae lineage.


Assuntos
Antineoplásicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Pirimidinas/química , Evolução Molecular , Fluoruracila/farmacologia , Proteínas Fúngicas/química , Regulação Fúngica da Expressão Gênica , Genes Fúngicos , Genoma Fúngico , Modelos Genéticos , Filogenia , Saccharomyces/metabolismo , Fatores de Tempo , Uracila/química , Uracila/metabolismo
5.
Virology ; 332(2): 676-90, 2005 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-15680433

RESUMO

Feline immunodeficiency virus (FIV) made defective in the accessory gene ORF-A were previously shown to be greatly attenuated in its ability to replicate in lymphocytes but to grow normally or near normally in other cell types. Here, we examined whether FIV thus mutated could protect specific pathogen-free cats against challenge with ex vivo fully virulent homologous virus. No reversion of the vaccinating infections to wild type ORF-A was noted over 22 months of in vivo infection. Following challenge, 6/6 unvaccinated control cats became readily and heavily infected. In contrast, 3/9 vaccinees showed no evidence of the challenge virus over a 15-month observation period. In the other vaccinees, the challenge virus was predominant for various periods of time, but pre-existing viral loads and CD4 lymphocyte counts were either unaffected or altered only marginally and transiently. These findings show that ORF-A-defective FIV should be further examined as a candidate live attenuated vaccine.


Assuntos
Síndrome de Imunodeficiência Adquirida Felina/virologia , Vírus da Imunodeficiência Felina/genética , Vírus da Imunodeficiência Felina/imunologia , RNA Viral/genética , Vacinas Atenuadas , Vacinas Virais , Sequência de Aminoácidos , Animais , Sequência de Bases , Gatos , DNA Viral/genética , Vírus Defeituosos/genética , Vírus Defeituosos/imunologia , Dados de Sequência Molecular , RNA Viral/imunologia , Alinhamento de Sequência
6.
Yeast ; 18(9): 775-80, 2001 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-11427959

RESUMO

The ZbTPI1 gene encoding triose phosphate isomerase (TIM) was cloned from a Zygosaccharomyces bailii genomic library by complementation of the Saccharomyces cerevisiae tpi1 mutant strain. The nucleotide sequence of a 1.5 kb fragment showed an open reading frame (ORF) of 746 bp, encoding a protein of 248 amino acid residues. The deduced amino acid sequence shares a high degree of homology with TIMs from other yeast species, including some highly conserved regions. The analysis of the promoter sequence of the ZbTPI1 revealed the presence of putative motifs known to have regulatory functions in S. cerevisiae. The GenBank Accession No. of ZbTPI1 is AF325852.


Assuntos
Triose-Fosfato Isomerase/genética , Zygosaccharomyces/enzimologia , Zygosaccharomyces/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Genes Fúngicos/genética , Teste de Complementação Genética , Dados de Sequência Molecular , Saccharomyces cerevisiae/genética , Alinhamento de Sequência , Análise de Sequência de DNA , Triose-Fosfato Isomerase/química , Triose-Fosfato Isomerase/metabolismo , Zygosaccharomyces/crescimento & desenvolvimento
7.
Brain Res ; 854(1-2): 35-41, 2000 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-10784104

RESUMO

The wide therapeutic spectrum of fluoxetine (e.g., antidepressant, antipanic, antiphobic, antiobsessive, analgesic, antimigraine) requires long-term administration and adaptive changes. To test whether adaptation involves the serotonin (5-HT) transporters, we measured the effects of fluoxetine on the regional cerebral metabolic rate for glucose (rCMRglc) in control rats or in rats pretreated for 2 weeks with fluoxetine (8 mg/kg, i.p., daily, 2 days wash out); rCMRglc was measured in 56 brain regions, using the quantitative [14C]deoxyglucose technique, at 30 min after i.p. administration of fluoxetine 0.4, 4 or 40 mg/kg, i.p., to non-pretreated rats or fluoxetine 4 mg/kg to pretreated rats. In non-pretreated rats, fluoxetine reduced rCMRglc in a dose-dependent fashion in 4 (7%, mean decrease 11%), 28 (50%, mean decrease 23%) and 37 (66%, mean decrease 32%) brain regions. In chronic fluoxetine-pretreated rats, fluoxetine decreased rCMRglc to a substantially lesser degree (eight regions, 14%; mean decrease, 10%). Subcortical brain regions (i.e., hypothalamic paraventricular, locus coeruleus and basal ganglia nuclei) that mediate the physiological responses to stress were very sensitive to fluoxetine acutely and subsensitive after chronic treatment. As kinetic tolerance to fluoxetine does not occur during chronic administration, the diminished rCMRglc responsivity to fluoxetine reflects dynamic, adaptive tolerance of 5-HT transporters and, consequently, increased synaptic 5-HT concentrations; the findings suggest that fluoxetine may be therapeutic by increasing the 5-HT-negative modulation upon areas that drive the abnormally hyperactive responses to stress found in several neuropsychiatric conditions.


Assuntos
Encéfalo/metabolismo , Fluoxetina/farmacologia , Glucose/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Fluoxetina/uso terapêutico , Masculino , Ratos , Ratos Endogâmicos F344 , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Fatores de Tempo , Distribuição Tecidual
8.
Vaccine ; 18(1-2): 119-30, 1999 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-10501242

RESUMO

The feline immunodeficiency virus (FIV) provides an excellent model system for AIDS vaccination studies. In the present experiments we investigated the immunogenicity and the protective activity of two inactivated vaccines prepared from a primary virus isolate. One vaccine was composed of whole virus inactivated with paraformaldehyde and then purified (WIV) and the other of viral proteins extracted with Tween-ether (TEV). Both vaccines elicited robust antiviral responses, but neither conferred appreciable levels of resistance against systemic challenge with the homologous virus. In addition, we tested whether the WIV vaccine, that had appeared more immunogenic, could protect against nontraumatic intravaginal exposure to FIV-infected cells. Although the proportions of control and vaccinated animals that became infected following mucosal challenge were similar, the vaccinees had significantly lower viral burdens than the controls, thus suggesting that immunisation with the WIV vaccine had limited FIV replication following intravaginal challenge.


Assuntos
Síndrome de Imunodeficiência Adquirida Felina/prevenção & controle , Vírus da Imunodeficiência Felina/imunologia , Viremia/prevenção & controle , Animais , Anticorpos Antivirais/sangue , Gatos , Feminino , Imunização , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Vacinas de Produtos Inativados/imunologia , Vagina
9.
J Virol ; 73(1): 1-10, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9847300

RESUMO

The feline immunodeficiency virus (FIV) cat model is extensively used to investigate possible vaccination approaches against AIDS in humans. Although consistent levels of protection have been achieved with FIV, as with other model systems, by immunizing with whole inactivated virus or fixed infected cells, the mechanisms responsible for protection are elusive. In previous studies we showed that cats immunized with a vaccine consisting of fixed infected cells were protected or unprotected against cell-free or cell-associated FIV challenge depending on the time interval between completion of vaccination and challenge. In an attempt to define possible humoral immune correlates of protection, selected sera harvested at the times of challenge from such cats were examined for anti-FIV-antibody titers and properties by using binding and functional immunological assays. Binding assays included quantitative Western blotting, enzyme-linked tests for antibodies to FIV glycoproteins and immunodominant linear epitopes, and tests for measuring conformation dependence and avidity of anti-viral-envelope antibodies. Functional assays included virus neutralization performed with two different cell substrates, complement- and antibody-dependent virolysis, blocking of reverse transcriptase, and an assay that measured the ability of sera to prevent FIV growth in cocultures of infected and uninfected cells. Despite the wide spectrum of parameters investigated, no correlation between vaccine-induced protection and the humoral parameters measured was noted.


Assuntos
Vacinas contra a AIDS/imunologia , Anticorpos Antivirais/sangue , Vírus da Imunodeficiência Felina/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Afinidade de Anticorpos , Gatos , Produtos do Gene env/imunologia , Vacinação
10.
Neuropsychopharmacology ; 13(3): 215-22, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8602894

RESUMO

To determine if reported reductions of regional cerebral metabolic rates for glucose (rCMRglc) induced by the tryciclic antidepressant clomipramine (CMI) (10 mg/kg) are due to a presynaptic action on serotonin (5-HT) terminals, 3-month-old Fischer-344 rats were given parachloroamphetamine (PCA), a serotonin neurotoxin. rCMRglc was measured 3 weeks later in 55 brain regions after the administration of saline or CMI using the quantitative autoradiographic [14C]2-deoxyglucose procedure. PCA alone increased rCMRglc in the visual cortex. CMI alone reduced rCMRglc in 18 (33%) of the studied regions, including telencephalic, diencephalic, limbic, and brain stem areas. In PCA-lesioned rats, metabolic responses to CMI (10 mg/kg) were greatly reduced, and significant rCMRglc decreases were observed only in 4 (7%) of the brain areas, including the hippocampus and raphe nuclei. Abolition by PCA of the metabolic responses to CMI confirms that CMI, at the dose studied, reduces rCMRglc via a presynaptic mechanism, likely the 5-HT reuptake sites.


Assuntos
Antidepressivos Tricíclicos/farmacologia , Encéfalo/metabolismo , Clomipramina/farmacologia , Desoxiglucose/metabolismo , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Serotoninérgicos/administração & dosagem , p-Cloroanfetamina/administração & dosagem , Animais , Encéfalo/efeitos dos fármacos , Química Encefálica , Metabolismo Energético , Masculino , Ratos , Ratos Endogâmicos F344
11.
Brain Res ; 677(2): 213-20, 1995 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-7552245

RESUMO

In this study we compared the effects of the anxiolytic buspirone on behavior and regional cerebral metabolic rates for glucose (rCMRglc) with those of the reference serotonin (5-HT)1A agonist 8-hydroxy-2(di-N-propylamino)tetralin (DPAT). Behavioral effects were assessed by scoring the 5-HT syndrome. rCMRglc was measured in 56 brain regions by using the quantitative autoradiographic [14C]2-deoxyglucose technique, at 10 min after i.p. injection of DPAT (1 mg/kg) or buspirone (0.4, 4 and 40 mg/kg) in awake male Fischer-344 rats. Whereas DPAT produced an intense 5-HT syndrome, buspirone had no behavioral effect. A low dose (0.4 mg/kg) of buspirone reduced rCMRglc in 18 brain areas (32%), more markedly in limbic areas and raphe nuclei. These were the only rCMRglc effects buspirone had in common with the potent 5-HT1A agonist DPAT and suggest that low dose buspirone activates preferentially 5-HT1A receptors. Hence, this receptor subtype may mediate buspirone functional effects on the limbic system and, given the role of these brain areas in mood control, possibly buspirone therapeutic actions. High doses (4 and 40 mg/kg) of buspirone produced widespread rCMRglc decreases in 46 (82%) and 44 (79%) of the areas studied and increased rCMRglc in one brain area, the lateral habenula, that was not affected by DPAT or a low dose of buspirone. The topographic distribution and direction of rCMRglc changes by high doses of buspirone differ from those produced by the 5-HT1A agonist DPAT. Instead these changes resemble the rCMRglc effects of dopaminergic D2 antagonists like haloperidol and are consistent with some pharmacological and binding properties of buspirone.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/metabolismo , Buspirona/farmacologia , Glucose/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Desoxiglucose , Agonistas de Dopamina/farmacologia , Relação Dose-Resposta a Droga , Haloperidol/farmacologia , Masculino , Monitorização Fisiológica , Ratos , Ratos Endogâmicos F344 , Receptores de Dopamina D2/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Agonistas do Receptor de Serotonina/farmacologia , Tetra-Hidronaftalenos/farmacologia
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