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1.
Braz J Biol ; 83: e269317, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36722663

RESUMO

Bacteria may be the initial cause of certain pathologies as well as a secondary agent responsible for the development of complications such as pressure ulcer infections. Pressure ulcers are a persistent health problem, especially in immunocompromised patients, and associated with infection by opportunistic microorganisms with antimicrobial resistance, such as Klebsiella pneumoniae, highlight the need for the development of new antimicrobial approaches. Thus, the aim of this study was to evaluate the antibacterial and anti-adherent activity of Origanum vulgare L. (oregano) essential oil against Klebsiella pneumoniae strains, as well as the effect of its association with synthetic antimicrobials. To this end, the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) analyses were performed on microdilution plates. The assay of the Minimum Inhibitory Adherence Concentration (MIAC), with test tubes. As well as, the association study through the infusion disc method containing ampicillin (AMP), gentamicin (GEN), ciprofloxacin (CIP) and ceftriaxone (CEF). Therefore, it was possible to obtain that the essential oil of oregano presents antimicrobial and bactericidal activity, with MIC ranging between 128µg/mL and 256 µg/mL and MBC between 256 µg/mL and 512 µg/mL, on the tested K. pneumoniae strains. When used in association with ampicillin and gentamicin, oregano essential oil showed synergistic effect for some strains. Therefore, it is observed that the tested essential oil can act as a promising antibacterial in the treatment of diseases caused by K. pneumoniae.


Assuntos
Óleos Voláteis , Origanum , Humanos , Klebsiella pneumoniae , Antibacterianos/farmacologia , Ampicilina , Gentamicinas , Óleos Voláteis/farmacologia
2.
Braz J Biol ; 83: e269245, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36629625

RESUMO

The present study sought to evaluate the antibacterial activity of trans-anethole against food-borne strains of Enterobacter cloacae and Enterococcus faecalis. The study was performed using Minimum Inhibitory Concentration (MIC), and Minimum Bactericidal Concentration (MBC) methods, in addition, disc diffusion technique was used to evaluate the association of trans-anethole with synthetic antimicrobials. Minimum Inhibitory Concentration for Adherence (MICA) testing was also performed. The results revealed that trans-anethole presents no antibacterial activity at any of the concentrations used against the E. cloacae strains tested. However, trans-anethole presented antibacterial effect against five of the six E. faecalis bacterial strains tested, with MIC values ranging from 500 µg/mL to 1000 µg/mL. Further, when analyzing the MBC results against E. faecalis, it was observed that the compound presented values ranging from 500 µg/mL to 1000 µg/mL. As for the associations, it was observed that trans-anethole when combined with the antimicrobials ampicillin, gentamicin, ciprofloxacin, and ceftriaxone presented synergistic effect against most strains of E. faecalis. However, both trans-anethole and the control chlorhexidine (0.12%) presented no antibiofilm effects against strains of E. faecalis. In short, trans-anethole presented potential antibacterial against E. faecalis strains of food origin, and may upon further study, it may be used alone or in association with synthetic antimicrobials to combat infections caused by this bacterium.


Assuntos
Anti-Infecciosos , Enterococcus faecalis , Enterococcus , Antibacterianos/farmacologia , Anisóis/farmacologia , Anti-Infecciosos/farmacologia , Testes de Sensibilidade Microbiana
3.
Int Arch Occup Environ Health ; 94(3): 495-501, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33156391

RESUMO

PURPOSE: The present work aims to study the effects of whole body vibration (WBV) on bus fare collectors through the use of cognitive tests. It is of interest for all individuals working as bus fare collectors or any other activity where logic is of paramount importance and that is performed on a vibrating environment. METHODS: Laboratory simulations were performed in 24 volunteers employing a vibrating platform subjected to vertical vibration. The influence of WBV on cognition was assessed using the performance on a logic game. The frequencies used were 5 Hz and 30 Hz. The acceleration amplitude values were set up as 0.7 m/s2 and 0.2 m/s2. A daily commute was simulated, based on data of the public transport system in the city of Belo Horizonte. A vibration-free test was initially performed to serve as a basis for comparison. RESULTS: The data obtained in all situations were compared and statistically analyzed. At 5 Hz, variation only shows significant after 5 min of vibration ceased as if the residual effect had passed after 5 min of rest. The gender variable was not significant. However, the older the volunteer, the worse the performance. Regarding 30 Hz frequency, the hypotheses did not meet the condition of significance at 5% but showed an opposite tendency indicating, in this situation, a score increase. It is noticed that the female volunteers presented a better performance in relation to the male gender The residual effect lasts for less than 10 min for short exposure intervals, since the score of test 8, in 5 Hz and 30 Hz, show a reduction of performance. CONCLUSIONS: From the results, it was possible to conclude that the frequency of 5 Hz may be related to reduced performance for long exposure times while the 30 Hz frequency has positive effects on cognition as the exposure time increases. In fact, it is a tendency much more than a clear statistical finding. Regarding comfort, most reports related to the frequency of 5 Hz are linked to the sensation of discomfort and difficulty in focusing visually, whereas, for the frequency of 30 Hz, the reports indicate a feeling of muscular comfort and increased easiness of concentration.


Assuntos
Cognição , Veículos Automotores , Exposição Ocupacional , Vibração , Encéfalo , Feminino , Humanos , Masculino , Aplicativos Móveis , Testes Neuropsicológicos , Ocupações
4.
Soft Matter ; 16(34): 7950-7957, 2020 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-32766622

RESUMO

The aim of this work was to investigate the shear and lateral normal responses of a soft unidirectional fiber-reinforced material subjected to simple shear. The Poynting effect was also investigated. Soft composites were manufactured from a flexible adhesive reinforced by a single family of parallel and continuous fibers of nylon. Specimens with fibers oriented at an angle (-45°, 0°, 45° and 90°) with respect to the applied shear force were tested. A simple shear test apparatus was developed to measure shear and normal forces simultaneously. A standard reinforcing model based on strain-energy density function was used to verify the mechanical behavior of the soft composite with different fiber orientation. Results showed that the initial stiffness of the composite with fibers oriented at -45° and 45° was approximately the same and was higher than those at 0° and 90°. Also, there was no significant difference between values of initial stiffness for angles of 0° and 90° and the neat matrix. The effect of the stretching resistance of the fibers was more pronounced for fibers oriented at 45° and 90°. There was no Poynting effect for the neat matrix or for the composite with fibers at 0° while positive and negative Poynting effects were observed for fibers oriented at -45° and 45° (and 90°), respectively. The standard reinforcing model was only verified for a limited range of amount of shear due to composite failure. Fiber debonding and fiber buckling were observed in the composites with fibers oriented at 45° (and 90°) and -45°, respectively, at large deformations.

5.
Braz J Med Biol Res ; 44(11): 1177-83, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22052375

RESUMO

The aim of this study was to determine the impact of antiretroviral therapy on the lipid profile of human immunodeficiency virus (HIV) patients before and after the initiation of highly active antiretroviral therapy (HAART). This was a cross-sectional analysis of patients receiving HAART at a reference center in Belo Horizonte, Brazil, on the basis of medical records from 2002 to 2006. Patients were included if they had at least one lipid test or a clinical or laboratory diagnosis of dyslipidemia/lipodystrophy. Among the 692 patients, 620 met the eligibility criteria. The majority were males (66.5%), middle age (average 39 years), had a low educational level (60.4%), and low income (51.0%). HAART duration ranged from 11 days to 4.6 years, with a mean of 28.6 months (SD = ± 470.19 days). The prevalence of dyslipidemia/lipodystrophy nearly tripled (11.3% pre- and 32.4% post-HAART). Dyslipidemia was associated with older age (P = 0.007), nucleoside reverse transcriptase inhibitor (NRTI) + protease inhibitor (PI) regimens (P = 0.04), NRTI + non-NRTI (NNRTI) regimens (P = 0.026), the use of stavudine (d4T) in any regimen (P = 0.002) or in NRTI-based regimens (P = 0.006), and longer exposure to HAART (P < 0.000). In addition, there was no correlation between dyslipidemia and gender (P = 0.084). Only 2.0% of the patients received treatment for dyslipidemia during the trial. These results show a need for continuous monitoring of patients under antiretroviral therapy, particularly those using NRTI-based regimens, especially when combined with d4T and PIs. Secondly, interventions should be developed to correct metabolic changes.


Assuntos
Dislipidemias/epidemiologia , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/efeitos adversos , Lipodistrofia/epidemiologia , Inibidores da Transcriptase Reversa/efeitos adversos , Estavudina/efeitos adversos , Adolescente , Adulto , Idoso , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Brasil/epidemiologia , Estudos Transversais , Quimioterapia Combinada/efeitos adversos , Dislipidemias/induzido quimicamente , Feminino , Humanos , Lipodistrofia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Estatísticas não Paramétricas , Resultado do Tratamento , Adulto Jovem
6.
Braz. j. med. biol. res ; 44(11): 1177-1183, Nov. 2011. tab
Artigo em Inglês | LILACS | ID: lil-604282

RESUMO

The aim of this study was to determine the impact of antiretroviral therapy on the lipid profile of human immunodeficiency virus (HIV) patients before and after the initiation of highly active antiretroviral therapy (HAART). This was a cross-sectional analysis of patients receiving HAART at a reference center in Belo Horizonte, Brazil, on the basis of medical records from 2002 to 2006. Patients were included if they had at least one lipid test or a clinical or laboratory diagnosis of dyslipidemia/lipodystrophy. Among the 692 patients, 620 met the eligibility criteria. The majority were males (66.5 percent), middle age (average 39 years), had a low educational level (60.4 percent), and low income (51.0 percent). HAART duration ranged from 11 days to 4.6 years, with a mean of 28.6 months (SD = ± 470.19 days). The prevalence of dyslipidemia/lipodystrophy nearly tripled (11.3 percent pre- and 32.4 percent post-HAART). Dyslipidemia was associated with older age (P = 0.007), nucleoside reverse transcriptase inhibitor (NRTI) + protease inhibitor (PI) regimens (P = 0.04), NRTI + non-NRTI (NNRTI) regimens (P = 0.026), the use of stavudine (d4T) in any regimen (P = 0.002) or in NRTI-based regimens (P = 0.006), and longer exposure to HAART (P < 0.000). In addition, there was no correlation between dyslipidemia and gender (P = 0.084). Only 2.0 percent of the patients received treatment for dyslipidemia during the trial. These results show a need for continuous monitoring of patients under antiretroviral therapy, particularly those using NRTI-based regimens, especially when combined with d4T and PIs. Secondly, interventions should be developed to correct metabolic changes.


Assuntos
Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Dislipidemias/epidemiologia , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV/efeitos adversos , Lipodistrofia/epidemiologia , Inibidores da Transcriptase Reversa/efeitos adversos , Estavudina/efeitos adversos , Terapia Antirretroviral de Alta Atividade/efeitos adversos , Brasil/epidemiologia , Estudos Transversais , Quimioterapia Combinada/efeitos adversos , Dislipidemias/induzido quimicamente , Lipodistrofia/induzido quimicamente , Estatísticas não Paramétricas , Resultado do Tratamento
7.
Thromb Haemost ; 86(5): 1215-20, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11816710

RESUMO

We compared the anticoagulant, antithrombotic and bleeding effects of highly sulfated dermatan sulfates from invertebrates and their mammalian counterpart. An invertebrate dermatan sulfate containing 2-O-sulfated alpha-L-iduronic acid and 4-O-sulfated N-acetyl-beta-D-galactosamine residues is a potent anticoagulant due to a high heparin cofactor II activity. It inhibits thrombin due to the formation of a covalent complex with heparin cofactor II, as in the case of mammalian dermatan sulfate, but the effect occurs at lower concentrations for the invertebrate polysaccharide. Surprisingly, the invertebrate dermatan sulfate has a lower potency to prevent thrombus formation on an experimental model and a lower bleeding effect in rats than the mammalian dermatan sulfate. In contrast, another invertebrate dermatan sulfate, also enriched in 2-O-sulfated alpha-L-iduronic acid, but in this case sulfated at O-6 position of the N-acetyl-beta-D-galactosamine units, has no in vitro or in vivo anticoagulant activity, does not prevent thrombus formation but shows a bleeding effect similar to the mammalian glycosaminoglycan. Overall, these results demonstrate unbalanced effects of dermatan sulfates with different sulfation patterns on coagulation, thrombosis and bleeding, and raise interesting questions concerning the relationship among these three biological actions of sulfated polysaccharides.


Assuntos
Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Dermatan Sulfato/farmacologia , Hemorragia/induzido quimicamente , Trombose/tratamento farmacológico , Animais , Anticoagulantes/administração & dosagem , Anticoagulantes/química , Bovinos , Dermatan Sulfato/administração & dosagem , Dermatan Sulfato/química , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Cofator II da Heparina/metabolismo , Masculino , Ligação Proteica/efeitos dos fármacos , Ratos , Ratos Wistar , Especificidade da Espécie , Trombina/antagonistas & inibidores , Trombina/metabolismo , Trombose/prevenção & controle , Urocordados
8.
Rev Bras Biol ; 59(4): 663-78, 1999 Nov.
Artigo em Português | MEDLINE | ID: mdl-23505654

RESUMO

"Carrasco" is a closed, tall-shrubby, xerophilous vegetation on Quartz Sand soils between altitudes of 700 and 900 m on Ibiapaba and Araripe plateaus in the Brazilian semi-arid domain. As it is still very poorly known, this paper aims to describe the structure and composition of the woody community and its spatial variation in relation to the soil. One-hundred 10 x 10 m plots were located by pairs of random numbers in a coordinate system at the locality of Jaburuna (3 degrees 54'34"S, 40 degrees 59'24"W, about 830 m altitude), municipality of Ubajara, north Ibiapaba. All woody plants with a minimum stem diameter of 3 cm at ground level had their vertical height (not for climbers) and stem perimeter recorded. A soil extract from 0-50 cm depth was taken at the centre of each plot. Published surveys of other carrasco areas on the south Ibiapaba were considered for comparison. The community structure showed great dominance concentration, the most abundant species (Acacia langsdorffii, Piptadenia moniliformis, Thiloa glaucocarpa) varied between surveys. At Jaburuna 81% of all sampled plants were shrubs, 14% trees (the most with less than 10 cm of trunk diameter and 6 m height), and 5% climbers. Canberra distances and Jaccard's Indices were calculated from a primary matrix of 87 species (with 5 or more individuals) and 175 plots. Several methods of cluster analysis were employed, all showed great floristic variation from place to place. A matrix of soil physical and chemical variates per plot was constructed, and the canonical correspondence analysis was applied to both primary and soil matrices. Lower pH and higher sum of bases (e. g. Brunfelsia cuneifolia, Neojeobertia candoleana), higher content of gross sand (e. g. Acacia glomerosa, Aspidosperma subincanumn) and higher content of fine sand (e. g. Aspidosperma discolor, Hymenaea velutina) were the main variates separating species. The floristic richness at Jaburuna was of 74 species, and the surveys showed no difference in Shannon's diversity, which varied from 2.87 to 3.16 nats/individual.


Assuntos
Plantas/classificação , Altitude , Brasil , Ecossistema , Concentração de Íons de Hidrogênio , Microclima , Estruturas Vegetais/anatomia & histologia , Plantas/anatomia & histologia , Solo/química , Especificidade da Espécie
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