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1.
Artigo em Inglês | MEDLINE | ID: mdl-27821447

RESUMO

Invasive Candida albicans infections are a serious health threat for immunocompromised individuals. Fluconazole is most commonly used to treat these infections, but resistance due to the overexpression of multidrug efflux pumps is of grave concern. This study evaluated the ability of five synthetic organotellurium compounds to reverse the fluconazole resistance of C. albicans clinical isolates. Compounds 1 to 4, at <10 µg/ml, ameliorated the fluconazole resistance of Saccharomyces cerevisiae strains overexpressing the major C. albicans multidrug efflux pumps Cdr1p and Mdr1p, whereas compound 5 only sensitized Mdr1p-overexpressing strains to fluconazole. Compounds 1 to 4 also inhibited efflux of the fluorescent substrate rhodamine 6G and the ATPase activity of Cdr1p, whereas all five of compounds 1 to 5 inhibited Nile red efflux by Mdr1p. Interestingly, all five compounds demonstrated synergy with fluconazole against efflux pump-overexpressing fluconazole-resistant C. albicans clinical isolates, isolate 95-142 overexpressing CDR1 and CDR2, isolate 96-25 overexpressing MDR1 and ERG11, and isolate 12-99 overexpressing CDR1, CDR2, MDR1, and ERG11 Overall, organotellurium compounds 1 and 2 were the most promising fluconazole chemosensitizers of fluconazole-resistant C. albicans isolates. Our data suggest that these novel organotellurium compounds inhibit pump efflux by two very important and distinct families of fungal multidrug efflux pumps: the ATP-binding cassette transporter Cdr1p and the major facilitator superfamily transporter Mdr1p.


Assuntos
Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Fluconazol/farmacologia , Candida albicans/genética , Candida albicans/metabolismo , Farmacorresistência Fúngica/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/genética , Testes de Sensibilidade Microbiana , Compostos de Organotecnécio/farmacologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
3.
Lett Appl Microbiol ; 65(4): 306-312, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28712134

RESUMO

Infectious wastes are potential sources of pathogenic micro-organisms, which may represent a risk to the professionals who manage them. In this study, we aimed to characterize the infectious bacteria present in dental waste and waste workers. The dental waste produced over 24 h was collected and waste workers were sampled by swabbing. Isolate resistance profiles were characterized by Vitek® and PCR and biofilm formation by Congo Red agar, string test and microtitre assay. To assess similarity between the waste and the workers' samples, a random amplified polymorphic DNA test was used. Twenty-eight bacteria were identified as clinically relevant. The most frequent gene was blaTEM present in five Gram-negative micro-organisms, and one blaSHV in Klebsiella pneumoniae. All Pseudomonas aeruginosa were positive to extracellular polymeric substances formation, except one isolated from a worker. Klebsiella pneumoniae had negative results for the string test. Pseudomonas aeruginosa showed better adherence at 25°C after 48 h of incubation and K. pneumonia had the best biofilm formation at the same temperature, after 24 h. The similarity between P. aeruginosa recovered from dental waste and from workers was low, however, it is important to note that a pathogen was found on a worker's hands and that improvements in biosafety are required. SIGNIFICANCE AND IMPACT OF THE STUDY: Infectious dental waste can contain clinically relevant bacteria with important resistance and biofilm profiles. These micro-organisms could be transmitted to waste workers, other professionals and patients if the principles of biosafety measures are neglected. To our knowledge, no study has ever evaluated the microbial characterization and the potential contamination risk of dental infectious waste and waste handlers. The presence of clinically relevant bacteria in the hands and nasal mucosa of waste workers highlights the need for studies in this field to clarify the risk of these pathogens in dental healthcare services, and to stress the need for an efficient waste management.


Assuntos
Resíduos Odontológicos/análise , Mãos/microbiologia , Klebsiella pneumoniae/isolamento & purificação , Mucosa/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Biofilmes/crescimento & desenvolvimento , Instrumentos Odontológicos/microbiologia , Humanos , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/genética , Pseudomonas aeruginosa/classificação , Pseudomonas aeruginosa/genética , Gerenciamento de Resíduos , beta-Lactamases/genética
4.
Opt Express ; 24(26): 30149-30163, 2016 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-28059292

RESUMO

Qudits, d-level quantum systems, have been shown to provide a better resource for quantum key distribution and other Quantum Information protocols. It is customary to generate photonic qudits using more than one degree of freedom of the same photon. In much the same way, multi-qubit states are generated using only a pair of photons and ingenious ways to manipulate more than one degree of freedom independently. In contrast to such costly implementations in terms of quantum resources, we present the controlled generation of two copies of two-qudit states using four photons and a single degree of freedom, transverse momentum. The degree of entanglement within each pair was inferred by exploiting the availability of two copies of the same state, without the need of a full tomographic reconstruction of the states, and both highly-entangled and separable states were generated. We show theoretically that the set of states obtainable using our setup is very diverse, ranging from maximally entangled states of qudits to separable states.

5.
Microb Pathog ; 100: 312-318, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27725281

RESUMO

Coagulase-negative staphylococci (CNS) represent one of the most prevalent microorganisms in nosocomial infections worldwide, nevertheless little is known about their pathogenicity features. Thus, our aim was to characterize virulence aspects of CNS isolated from patients with bloodstream infections assisted in hospitals of Belo Horizonte, MG, Brazil. Strains were identified using bioMérieuxVitek® and for biofilm production evaluation, Congo Red Agar (CRA) and polystyrene plates were used. PCR was applied to detect icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr. For statistical analyses were used hierarchical cluster, chi-square test and correspondence. 59 strains were analyzed, being S. haemolyticus the most prevalent. On CRA, 96.5% were biofilm producer, whereas on polystyrene plate, 100% showed adhesion at different times evaluated. Regarding genotypic analyses, 15.2%, 38.9%, 8.4%, 49.1%, 76.2%, 23.7%, 1.6%, 30.5% and 38.9% were positive for icaA, icaB, icaC, atlE, sea, sec, sed, tsst-1 and agr, respectively. Six clusters were formed and frequency distributions of agr, atlE, icaA, icaB, sea, sec, tsst-1 differed (P < 0.001). In conclusion, all strains were biofilm producer, with high prevalence of atlE, and had potential of toxin production, with high prevalence of sea. According to the group-analyses, icaB showed relationship with the strong adherence in samples.


Assuntos
Toxinas Bacterianas/análise , Biofilmes/crescimento & desenvolvimento , Sepse/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/fisiologia , Aderência Bacteriana , Toxinas Bacterianas/genética , Técnicas de Tipagem Bacteriana , Brasil , Análise por Conglomerados , Infecção Hospitalar/microbiologia , Genótipo , Hospitais , Humanos , Reação em Cadeia da Polimerase , Staphylococcus/classificação , Staphylococcus/isolamento & purificação , Staphylococcus/metabolismo , Fatores de Virulência/análise , Fatores de Virulência/genética
6.
Acta Paediatr ; 105(5): e228-31, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26821362

RESUMO

AIM: The association between Helicobacter pylori infection and gastrointestinal symptoms is debatable in childhood. We examined the potential relationship between H. pylori infection and gastrointestinal symptoms in Brazilian children with nonulcer dyspepsia. METHODS: This prospective observational study analysed 240 Brazilian children and adolescents (68.7% girls) with chronic nonulcer dyspepsia, who underwent upper gastrointestinal endoscopy and biopsy. Their mean age was 9.8 years (range 4-17). Upper gastrointestinal symptoms, including abdominal pain, nausea, burning, early satiety, belching and weigh loss, were evaluated by a questionnaire and H. pylori infection was determined by histopathology of gastric biopsies. RESULTS: H. pylori infection was identified in 123/240 patients (52%). There was no significant association between the H. pylori infection and gastrointestinal symptoms and no relationship between the infection and abdominal pain or pain characteristics. However, nausea was significantly associated with the H. pylori infection, with an odds ratio of 1.76 and 95% confidence interval of 1.1-2.94 p < 0.03. Symptoms lasting longer than 12 months were significantly more frequent in children with pangastritis than in those with antral gastritis (p < 0.05). CONCLUSION: The prevalence of H. pylori infection was high in Brazilian children with nonulcer dyspepsia, but was not associated with specific signs and symptoms, except for nausea.


Assuntos
Dispepsia/microbiologia , Infecções por Helicobacter/complicações , Helicobacter pylori/isolamento & purificação , Dor Abdominal/microbiologia , Adolescente , Criança , Pré-Escolar , Doença Crônica , Dispepsia/diagnóstico por imagem , Dispepsia/patologia , Endoscopia Gastrointestinal , Feminino , Infecções por Helicobacter/diagnóstico , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/patologia , Humanos , Modelos Logísticos , Masculino , Náusea/microbiologia , Prevalência , Estudos Prospectivos
7.
Dis Aquat Organ ; 121(1): 49-57, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27596859

RESUMO

Monthly samples of smelt Osmerus eperlanus (Linnaeus, 1758) were collected from July 1985 to May 1986, in the river Elbe (Germany), and examined for infections with microsporidians. Two microsporidians were found: Glugea hertwigi Weissenberg, 1911, infecting the digestive tract and Pleistophora ladogenis Voronin, 1978, infecting the skeletal musculature. G. hertwigi infection led to the formation of xenomas, whereas P. ladogensis was characterized by diffuse infections, with the production of macroscopic visible thread-like or oval-shaped infection foci. Development of G. hertwigi in the host cells showed characteristics typical of the genus Glugea. The ultrastructural development of P. ladogensis showed features typical of the genus Pleistophora, without evidence of the production of 2 types of spores. Host reaction consisted of inflammatory tissue surrounding some of the infection foci as well as phagocytosis of spores. G. hertwigi was only found in juvenile smelt (<10 cm in length), whereas P. ladogensis infected smelts from 6 to 26 cm in length. Prevalence increased with fish length to a maximum value of 9.6%. Seasonal fluctuations in prevalence of infection were also found, with the lowest value in the winter months (2.5% in January 1986) and the highest in summer (11.8% in July 1985). The differences in prevalence of infection with fish length and date of sampling were significant. Additionally, samples of smelt caught in April 1986 from the rivers Eider and Ems revealed infections with P. ladogensis in the first river system only.


Assuntos
Doenças dos Peixes/parasitologia , Glugea/isolamento & purificação , Microsporidiose/veterinária , Osmeriformes , Pleistophora/isolamento & purificação , Animais , Doenças dos Peixes/epidemiologia , Alemanha/epidemiologia , Lansoprazol , Microsporidiose/epidemiologia , Microsporidiose/microbiologia , Mar do Norte/epidemiologia
8.
J Hum Nutr Diet ; 28(6): 666-74, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25420921

RESUMO

BACKGROUND: Current methods for assessing children's dietary intake, such as interviewer-administered 24-h dietary recall (24-h DR), are time consuming and resource intensive. Self-administered instruments offer a low-cost diet assessment method for use with children. The present study assessed the validity of the Portuguese self-administered, computerised, 24-h DR (PAC24) against the observation of school lunch. METHODS: Forty-one, 7-10-year-old children from two elementary schools, in Lisbon, were observed during school lunch followed by completion of the PAC24 the next day. Accuracy for reporting items was measured in terms of matches, intrusions and omissions; accuracy for reporting amounts was measured in terms of arithmetic and absolute differences for matches and amounts for omissions and intrusions; and accuracy for reporting items and amounts combined was measured in terms of total inaccuracy. The ratio of the estimated weight of food consumed with the actual weight consumed was calculated along with the limits of agreement using the method of Bland and Altman. RESULTS: Comparison of PAC24 against observations at the food level resulted in values of 67.0% for matches, 11.5% for intrusions and 21.5% for omissions. The mean for total inaccuracy was 3.44 servings. For amounts, accuracy was high for matches (-0.17 and 0.23 servings for arithmetic and absolute differences, respectively) and lower for omissions (0.61 servings) and intrusions (0.55 servings). PAC24 was found to under-estimate the weight of food on average by 32% of actual intake. CONCLUSIONS: PAC24 is a lower-burden procedure for both respondents and researchers and, with slight modification, comprises a promising method for assessing diet among children.


Assuntos
Registros de Dieta , Inquéritos sobre Dietas/métodos , Inquéritos sobre Dietas/estatística & dados numéricos , Comportamento Alimentar , Almoço , Autorrelato , Criança , Computadores , Feminino , Humanos , Masculino , Rememoração Mental , Portugal , Reprodutibilidade dos Testes , Instituições Acadêmicas , Sensibilidade e Especificidade
9.
J Dairy Sci ; 98(2): 947-59, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25434339

RESUMO

Our hypothesis was that fertility could be increased in a timed artificial insemination (TAI) protocol based on estradiol (E2) and progesterone (P4) by combining GnRH with E2-benzoate at the start of the protocol to increase circulating P4 during preovulatory follicle development and by using 2 prostaglandin F2α (PGF) treatments at the end to decrease P4 near TAI. Lactating Holstein cows (n=1,808) were randomly assigned during the cool or hot season of the year to receive TAI (d 0) following 1 of 3 treatments: (1) control: controlled internal drug-release insert + 2mg of E2-benzoate on d -11, PGF on d -4, controlled internal drug-release insert withdrawal + 1.0mg of E2-cypionate on d -2, and TAI on d 0; (2) 2PGF: identical to control protocol with addition of a second PGF treatment on d -2; (3) GnRH: identical to 2PGF protocol with addition of a 100-µg GnRH treatment on d -11. Pregnancy diagnoses were performed on d 32 and 60 after TAI. Season had major effects on many reproductive measures, with cool season greater than hot season in percentage of cows with corpus luteum (CL) at PGF (62.9 vs. 56.2%), ovulatory follicle diameter (15.7 vs. 14.8mm), expression of estrus (86.7 vs. 79.9%), ovulation following the protocol (89.7 vs. 84.3%), and pregnancies per artificial insemination (P/AI; 45.4 vs. 21.4%). The GnRH protocol increased percentage of cows with CL (control=56.9%; 2PGF=55.8%; GnRH=70.5%) and P4 at PGF (control=3.28±0.22; 2PGF=3.35±0.22; GnRH=3.70±0.21ng/mL), compared with control and 2PGF protocols. The GnRH protocol increased P/AI at the pregnancy diagnosis at 32d [37.3% (219/595)] and 60d [31% (179/595)] after TAI, compared with control [30.0% (177/604); 25.1% (145/604)], with intermediate results with 2PGF protocol [33.2% (196/609); 28.0% (164/609)]. The positive effects of GnRH treatment on P/AI were only detected during the cool season (GnRH=50.9%; 2PGF=44.2%; control=41.0%) and not during the hot season. In addition, the effect of GnRH was only observed in cows with low P4 (<3ng/mL) at the start of the protocol and not in cows that began the protocol with high P4. Furthermore, presence of CL at PGF interacted with follicle diameter such that cows with a CL at PGF had greater P/AI if they ovulated larger rather than smaller follicles near TAI. Thus, fertility to TAI can be improved by inducing ovulation at the beginning of an E2/P4-based protocol using GnRH treatment, particularly during the cool season of the year and in cows with low P4 at the start of the protocol.


Assuntos
Dinoprosta/farmacologia , Estradiol/farmacologia , Sincronização do Estro/métodos , Inseminação Artificial/veterinária , Estações do Ano , Animais , Bovinos , Corpo Lúteo/efeitos dos fármacos , Estro/efeitos dos fármacos , Feminino , Fertilidade/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/farmacologia , Gonadotropinas , Inseminação Artificial/métodos , Lactação , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Indução da Ovulação , Ocitócicos/farmacologia , Gravidez , Progesterona/farmacologia , Reprodução/efeitos dos fármacos , Temperatura
10.
Genet Mol Res ; 13(3): 7826-38, 2014 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-25299097

RESUMO

Hylidae is one of the most species-rich families of anurans, and 40% of representatives in this group occur in Brazil. In spite of such remarkable diversity, little is known about this family and its taxonomical and systematic features. Most hylids have 2n = 24, even though most of the cytogenetic data are mainly obtained based on the conventional chromosomal staining and are available for only 16% of Hypsiboas species, a genus accounting for about 10% of the hylid diversity. In this study, cytogenetic data of distinct species and populations of Hypsiboas were analyzed, and the evolutionary dynamics of chromosomal macro- and microstructure of these amphibians were discussed. Contrary to the conservativeness of 2n = 24, this genus is characterized by a high variation of chromosomal morphology with as much as 8 karyotype patterns. Differences in the number and location of nucleolus organizer regions and C-bands allowed the identification of geographical variants within nominal species and cytotaxonomical chromosomal markers. Comparative analyses revealed a strong phylogeographic relationship between chromosomal patterns in this group.


Assuntos
Anuros/genética , Cromossomos , Evolução Molecular , Animais , Cariotipagem , Especificidade da Espécie
11.
DNA Repair (Amst) ; 129: 103532, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37453244

RESUMO

Organisms have evolved a complex system, called the DNA damage response (DDR), which maintains genome integrity. The DDR is responsible for identifying and repairing a variety of lesions and alterations in DNA. DDR proteins coordinate DNA damage detection, cell cycle arrest, and repair, with many of these events regulated by protein phosphorylation. In the human proteome, 23 proteins contain the BRCT (BRCA1 C-Terminus domain) domain, a modular signaling domain that can bind phosphopeptides and mediate protein-protein interactions. BRCTs can be found as functional single units, tandem (tBRCT), triplet (tpBRCT), and quartet. Here we examine the evolution of the tpBRCT architecture present in TOPBP1 (DNA topoisomerase II binding protein 1) and ECT2 (epithelial cell transforming 2), and their respective interaction partners RAD9 (Cell cycle checkpoint control protein RAD9) and CYK-4 (Rac GTPase-activating protein 1), with a focus on the conservation of the phosphopeptide-binding residues. The pair TOPBP1-RAD9 arose with the Eukaryotes and ECT2-CYK-4 with the Eumetazoans. Triplet structural and functional characteristics were conserved in almost all organisms. The first unit of the triplet (BRCT0) is different from the other two BRCTs but conserved between orthologs for both TOPBP1 and ECT2. BRCT domain evolution simulations suggest a trend to retain the singlet or towards two or three BRCT copies per protein consistent with functional tBRCT and tpBRCT architectures. Our results shed light on the emergence of the function and architecture of multiple BRCT domain organizations and provide information about the evolution of the BRCT triplet. Knowledge of BRCT domain evolution can improve the understanding of DNA damage response mechanisms and signal transduction in DDR.


Assuntos
Proteína BRCA1 , Proteínas de Ciclo Celular , Humanos , Proteína BRCA1/metabolismo , Domínios Proteicos , Proteínas de Ciclo Celular/metabolismo , Dano ao DNA , Transdução de Sinais , Fosforilação , Ligação Proteica
12.
Braz J Biol ; 83: e274888, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38055577

RESUMO

Ateleia glazioveana Baill. is a pioneer, rustic and can be used for forest recovery. This work aimed to study the process of physiological maturation of this species. The research was carried out in the city of Alegre - ES, the trees were identified in the floral anthesis and accompanied during the filling of the fruits and development of the seeds until the complete maturation. The fruits were harvested at the following stages 7, 14, 21, 28, 35 and 42 days after anthesis, and characterized according to: morphometry, moisture, fresh and dry mass of fruits and seeds, germination, germination speed index, shoot and root length and dry mass of seedlings. The regression equations were adjusted for the main characteristics analyzed as a function of the harvest period. The point of physiological maturity of timbó occurred at 42 days after anthesis.


Assuntos
Fabaceae , Sementes , Germinação/fisiologia , Plântula , Frutas
13.
Br J Cancer ; 107(6): 977-87, 2012 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-22892389

RESUMO

BACKGROUND: Fatty acid synthase (FASN) is overexpressed and associated with poor prognosis in several human cancers. Here, we investigate the effect of FASN inhibitors on the metastatic spread and angiogenesis in experimental melanomas and cultured melanoma cells. METHODS: The lung colonisation assay and cutaneous melanomas were performed by the inoculation of mouse melanoma B16-F10 cells in C57BL6 mice. Blood vessel endothelial cells (RAEC and HUVEC) were applied to determine cell proliferation, apoptosis, and the formation of capillary-like structures. Vascular endothelial growth factor A (VEGFA) expression was evaluated by quantitative RT-PCR and ELISA in B16-F10, human melanoma (SK-MEL-25), and human oral squamous carcinoma (SCC-9) cells. Conditioned media from these cancer cell lines were used to study the effects of FASN inhibitors on endothelial cells. RESULTS: B16-F10 melanoma-induced metastases and angiogenesis were significantly reduced in orlistat-treated mice. Fatty acid synthase inhibitors reduced the viability, proliferation, and the formation of capillary-like structures by RAEC cells, as well as the tumour cell-mediated formation of HUVEC capillary-like structures. Cerulenin and orlistat stimulated the production of total VEGFA in B16-F10, SK-MEL-25, and SCC-9 cells. Both drugs also enhanced VEGFA(121), (165), (189,) and (165b) in SK-MEL-25 and SCC-9 cells. CONCLUSION: FASN inhibitors reduce metastasis and tumour-induced angiogenesis in experimental melanomas, and differentially modulate VEGFA expression in B16-F10 cells.


Assuntos
Antineoplásicos/farmacologia , Inibidores Enzimáticos/farmacologia , Ácido Graxo Sintases/antagonistas & inibidores , Lactonas/farmacologia , Neoplasias Pulmonares/prevenção & controle , Melanoma Experimental/tratamento farmacológico , Melanoma/tratamento farmacológico , Neovascularização Patológica/prevenção & controle , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/secundário , Melanoma/irrigação sanguínea , Melanoma/secundário , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Bucais/tratamento farmacológico , Orlistate , RNA Interferente Pequeno , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos
14.
Br Poult Sci ; 53(1): 71-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22404807

RESUMO

1. The objective was to evaluate the occurrence of cultivable components of the Bacteroides fragilis group in faeces of broiler chickens and their antimicrobial susceptibility patterns. 2. Faecal samples of 36 × 45-d-old Cobb broilers of both sexes from 15 different flocks on one farm were diluted 10-fold and plated on to Bacteroides-bile-esculin agar for colony count and isolation. Identification was by molecular methods and antimicrobial susceptibility in the agar dilution assay. 3. A total of 236 isolates was recovered from a mean population of 3·32 × 10(7 )colony-forming units/g of faeces. B. fragilis was shown to be the predominant Bacteroides species (45·3%), followed by B. distasonis (35·6%), B. vulgatus (8·9%), B. ovatus (2·5%) and B. stercoris (1·3%). 4. Among 204 bacterial isolates tested, high resistance to ampicillin (98·5%), norfloxacin (95·1%) and tetracycline (88·2%) were observed. High (89·7%) multi-drug resistance was observed to 3-7 of the tested drugs. 5. Components of the B. fragilis group were sub-dominant in broiler faecal microbiota, with a different species pattern compared with human and high antimicrobial multi-drug resistance.


Assuntos
Antibacterianos/farmacologia , Bacteroides/classificação , Bacteroides/efeitos dos fármacos , Galinhas , Farmacorresistência Bacteriana Múltipla , Fezes/microbiologia , Animais , Bacteroides/isolamento & purificação , Feminino , Masculino
15.
J Helminthol ; 86(3): 368-72, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21875447

RESUMO

The helminth parasite fauna of the oceanic horse mackerel Trachurus picturatus Bowdich 1825, caught off the Madeira Islands was composed of six different taxa. Prevalence and abundance of larval Anisakis sp. (Nematoda: Anisakidae) and Nybelinia lingualis (Trypanorhyncha: Tentaculariidae), the most common parasite taxa, were 24.3%, 0.9 and 37.9%, 0.7, respectively. Bolbosoma vasculosum (Acanthocephala: Polymorphidae) and the monogeneans Heteraxinoides atlanticus (Monogenea: Heteraxinidae) and Pseudaxine trachuri (Monogenea: Gastrocotylidae) were comparatively rare. The depauperate helminth fauna of the oceanic horse mackerel at Madeira compared to other geographical regions of the north-eastern Atlantic, namely the Azores banks and the West African coast, may be attributed to the paucity of nutrients off oceanic islands and to a low density of the fish population.


Assuntos
Perciformes/parasitologia , Trematódeos/isolamento & purificação , Animais , Portugal
16.
Braz J Med Biol Res ; 55: e12381, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36350974

RESUMO

Glial cells have been implicated in temporal lobe epilepsy in humans and in its models. Astrocytes are lost in several brain regions after acute seizures induced by pilocarpine and may suffer hyperplasia at subsequent time points. This study investigated the effect of N-methyl-(2S,4R)-trans-4-hydroxy-L-proline (NMP) on astrocytes exposed to cytotoxic concentrations of pilocarpine. Astrocytes were incubated with pilocarpine (half maximal inhibitory concentration (IC50)=31.86 mM) for 24 h. Afterwards, they were treated with NMP at concentrations ranging from 3.12 to 100 µg/mL for 24 h. Cell viability was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cytoplasmic reactive oxygen species (ROS) and mitochondrial transmembrane potential (ΔΨm) were analyzed by flow cytometry using 2',7'-dichlorofluorescein diacetate (DCFH-DA) and rhodamine-123 (Rho123), respectively. Expression of glial fibrillary acidic protein (GFAP) and voltage-dependent anion channel-1 (VDAC-1) were measured by western blot. Pilocarpine significantly decreased cell viability and mitochondrial potential and increased ROS concentration significantly by 6.7 times compared to the control. NMP concentrations ≥25 µg/mL protected astrocytes against pilocarpine-induced injury in a concentration-dependent manner. Concomitantly, NMP reduced cytoplasmic ROS accumulation to 27.3, 24.8, and 12.3% in the groups treated with 25, 50, and 100 µg/mL NMP, respectively. NMP also protected mitochondria from pilocarpine-induced depolarization. These effects were associated with improvement of pilocarpine-induced GFAP and VDAC-1 overexpression, which are important biomarkers of astrocyte dysfunction. In conclusion, the improvement of ROS accumulation, VDAC-1 overexpression, and mitochondrial depolarization are possible mechanisms of the NMP protective action on reactive astrocytes.


Assuntos
Pilocarpina , Sapotaceae , Humanos , Pilocarpina/farmacologia , Astrócitos , Espécies Reativas de Oxigênio/metabolismo , Sapotaceae/metabolismo
17.
Opt Express ; 19(4): 3715-29, 2011 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-21369197

RESUMO

Control of spatial quantum correlations in bi-photons is one of the fundamental principles of Quantum Imaging. Up to now, experiments have been restricted to controlling the state of a single bi-photon, by using linear optical elements. In this work we demonstrate experimental control of quantum correlations in a four-photon state comprised of two pairs of photons. Our scheme is based on a high-efficiency parametric downconversion source coupled to a double slit by a variable linear optical setup, in order to obtain spatially encoded qubits. Both entangled and separable pairs have been obtained, by altering experimental parameters. We show how the correlations influence both the interference and diffraction on the double slit.

18.
Opt Express ; 18(24): 24423-33, 2010 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-21164789

RESUMO

We report minimal quantum state tomography with spatial qubits created by a pair of parametric down converted twin-photons passing through a double-slit. A novel experimental setup is used, which includes a Spatial Light Modulator, as a fundamental tool, to reconstruct the state density matrix. The theory needed to perform a minimal quantum tomography is described. The density matrix is experimentally obtained for the two-qubit photonic states in spatial variables.

19.
Amino Acids ; 39(1): 135-44, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19946788

RESUMO

LyeTx I, an antimicrobial peptide isolated from the venom of Lycosa erythrognatha, known as wolf spider, has been synthesised and its structural profile studied by using the CD and NMR techniques. LyeTx I has shown to be active against bacteria (Escherichia coli and Staphylococcus aureus) and fungi (Candida krusei and Cryptococcus neoformans) and able to alter the permeabilisation of L: -alpha-phosphatidylcholine-liposomes (POPC) in a dose-dependent manner. In POPC containing cholesterol or ergosterol, permeabilisation has either decreased about five times or remained unchanged, respectively. These results, along with the observed low haemolytic activity, indicated that antimicrobial membranes, rather than vertebrate membranes seem to be the preferential targets. However, the complexity of biological membranes compared to liposomes must be taken in account. Besides, other membrane components, such as proteins and even specific lipids, cannot be discarded to be important to the preferential action of the LyeTx I to the tested microorganisms. The secondary structure of LyeTx I shows a small random-coil region at the N-terminus followed by an alpha-helix that reached the amidated C-terminus, which might favour the peptide-membrane interaction. The high activity against bacteria together with the moderate activity against fungi and the low haemolytic activity have indicated LyeTx I as a good prototype for developing new antibiotic peptides.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Venenos de Aranha/química , Animais , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antifúngicos/química , Antifúngicos/isolamento & purificação , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/isolamento & purificação , Candida/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Relação Dose-Resposta a Droga , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Fosfatidilcolinas/antagonistas & inibidores , Estrutura Secundária de Proteína , Aranhas , Staphylococcus aureus/efeitos dos fármacos
20.
Lett Appl Microbiol ; 51(4): 370-6, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20723041

RESUMO

AIMS: This study was undertaken to detect, identify and determine antifungal susceptibility of yeast strains isolated from dental solid waste and to evaluate airborne fungi in the Brazilian dental health care environment and in the waste storage room. METHODS AND RESULTS: A group of 17 yeast strains were identified by macroscopic and microscopic characteristics, API 20C Aux system and Multiplex PCR. All 104 airborne fungal colonies were identified by macroscopic and microscopic morphology. The CLSI broth microdilution method was utilized as the susceptibility test. Candida parapsilosis was the prevailing yeast species recovered from waste, followed by Rhodotorula glutinis. Three strains of Candida guilliermondii presented minimal inhibitory concentration values considered to be susceptible dose dependent (2 µg ml(-1)) to voriconazole. Of all airborne fungal species, 69% were recovered from the waste storage room and 31% were recovered from the clinical/surgical environment. Most of them were identified as Cladosporium spp. CONCLUSIONS: These findings reinforce the potential risk of waste handling and point out the need for safe management to minimize the spread of these agents to the environment. Filamentous fungi isolation in almost all sampled environments indicates that a periodic monitoring of airborne microbiota in the dental health care service environment is required. SIGNIFICANCE AND IMPACT OF THE STUDY: The survival of yeast strains for 48 h suggests that dental waste should be carefully controlled and monitored.


Assuntos
Microbiologia do Ar , Serviços de Saúde Bucal , Resíduos Odontológicos/análise , Fungos/isolamento & purificação , Antifúngicos/farmacologia , Brasil , Candida/classificação , Candida/efeitos dos fármacos , Candida/isolamento & purificação , Fungos/classificação , Fungos/efeitos dos fármacos , Fungos/genética , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase/métodos , Rhodotorula/classificação , Rhodotorula/efeitos dos fármacos , Rhodotorula/isolamento & purificação , Especificidade da Espécie
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