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1.
J Comp Physiol B ; 191(3): 493-502, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33598785

RESUMO

Tambaqui (Colossoma macropomum) are a model species for tropical fish physiology, but details are lacking about their ionoregulatory response to acid waters. To provide specifics, we measured unidirectional Na+ fluxes in low pH waters. Sodium influx ([Formula: see text]) was uninhibited during acute exposure to pH 4.5 and 3.5, and Na efflux ([Formula: see text]) rose only slightly at pH 3.5; net Na+ flux ([Formula: see text]) remained positive at all pH. Similarly, during 24 h transfer to pH 3.5 [Formula: see text], [Formula: see text], and [Formula: see text] were unchanged at all times. Taking a closer look at the mechanism of Na+ transport in the gills of tambaqui we found that [Formula: see text] was uninhibited by HMA, a Na+/H+-exchanger blocker, and Benzamil, a Na+-channel inhibitor, casting doubt on their role in Na+ uptake in this fish. Measurement of Na+/K+-ATPase (NKA) and H+-ATPase (VHA) activity showed that neither changed at low pH compared to measurements at pH 6.5. Western blot analysis of ATPase expression saw no changes in amount of NKA and VHA at low pH, and immunohistochemistry showed expression of both NKA and VHA on lamellae and interlamellar region of tambaqui gills and that both proteins co-localized to the same gill cells. Location of expression also did not change in low pH water. Amazingly, tambaqui seem unaffected by pH 3.5 water, making them one of the most acid-tolerant fish species examined so far. In addition, they appear to share key ionoregulatory traits with other fish of the order Characiformes, which suggest a common origin for the ionoregulatory attributes.


Assuntos
Caraciformes , Brânquias , Animais , Concentração de Íons de Hidrogênio , Sódio , Água
2.
Environ Sci Pollut Res Int ; 22(9): 6766-77, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25424031

RESUMO

The purpose of this research is to develop a direct spectrometric approach to monitor soils and waters, at a lower cost than the widely used chromatographic techniques; a spectrometric approach that is effective, reliable, fast, easy to implement, and without any use of organic solvents whose utilization is subject to law limitation. It could be suitable at least as an alert method in case of massive contamination. Here, we present for the first time a catalog of excitation-emission and total synchronous fluorescence maps that may be considered as fingerprints of a series of homologated pesticides, in large use in Morocco, aiming at a direct detection of their remains in agricultural soils and neighboring waters. After a large survey among farmers, agricultural workers and product distributors in two important agricultural regions of Morocco (Doukkala-Abda and Sebou basin), 48 commercial pesticides, which are fluorescent, were chosen. A multi-component spectral database of these targeted commercial pesticides was elaborated. For each pesticide, dissolved in water at the lowest concentration giving a no-noise fluorescence spectrum, the total excitation-emission matrix (TEEM), the total synchronous fluorescence matrix (TSFM) in addition to synchronous fluorescence spectra (SFS) at those offsets giving the highest fluorescence intensity were recorded. To test this preliminary multi-component database, two real soil samples, collected at a wheat field and at a vine field in the region of Doukkala, were analyzed. Remains of the commercial Pirimor (Carbamate) and Atlantis (Sulfonylurea) were identified by comparison of the recorded TEEM, TSFM, and SFS to those of the preliminary catalog at one hand, and on the basis of the results of a field pre-survey. The developed approach seems satisfactory, and the fluorimetric fingerprint database is under extension to a higher number of fluorescent pesticides in common use among the Moroccan agricultural regions.


Assuntos
Praguicidas/análise , Poluentes do Solo/análise , Poluentes Químicos da Água/análise , Agricultura , Bases de Dados de Compostos Químicos , Marrocos , Espectrometria de Fluorescência/métodos
3.
Oper Dent ; 39(6): 588-94, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25084108

RESUMO

The objective of this longitudinal clinical randomized trial was to evaluate the clinical performance of a nanofilled and a nanohybrid resin composite in Class I occlusal restorations of posterior teeth over the course of 54 months. Forty-one adolescents participated in the study. The teeth were restored with Adper Single Bond 2 (3M ESPE) and nanofilled (Filtek Z350, 3M ESPE), nanohybrid (Esthet-X, Dentsply) and microhybrid Filtek Z250 (3M ESPE) used as a control. After 54 months, the restorations were evaluated in accordance with the modified United States Public Health Service criteria. The McNemar and Friedman tests were used for statistical analysis, at a level of significance of 5%. Five failed restorations were observed during the follow-up. A change to unacceptable restoration occurred for one Esthet-X, two Filtek Z350, and two Filtek Z250 restorations, which received the clinically unacceptable score, Charlie, for both anatomic form and marginal adaptation. Secondary caries and postoperative sensitivity occurred in one Filtek Z250 and one Filtek Z350 restoration. When the five evaluation periods (baseline and six, 12, 30, and 54 months) were compared, significant differences were found in the marginal adaptation of Filtek Z250 and Filtek Z350. Significant differences in the roughness criteria (p=0.005) were also observed when the three composites were compared after 54 months (Filtek Z350 > Filtek Z250 > Esthet-X), always within clinically acceptable limits. The materials investigated showed acceptable clinical performance for Class I restoration after 54 months. Long-term reevaluations are necessary for a more detailed analysis of these composites.


Assuntos
Resinas Compostas , Restauração Dentária Permanente , Feminino , Humanos , Estudos Longitudinais , Masculino
4.
Artigo em Inglês | MEDLINE | ID: mdl-21660258

RESUMO

The efficacy of extracts and essential oils from Allium tuberosum, Coriandrum sativum, Cymbopogon martini, Cymbopogon winterianus, and Santolina chamaecyparissus was evaluated against Candida spp. isolates from the oral cavity of patients with periodontal disease. The most active oil was fractionated and tested against C. albicans biofilm formation. The oils were obtained by water-distillation and the extracts were prepared with macerated dried plant material. The Minimal Inhibitory Concentration-MIC was determined by the microdilution method. Chemical characterization of oil constituents was performed using Gas Chromatography and Mass Spectrometry (GC-MS). C. sativum activity oil upon cell and biofilm morphology was evaluated by Scanning Electron Microscopy (SEM). The best activities against planktonic Candida spp. were observed for the essential oil and the grouped F(8-10) fractions from C. sativum. The crude oil also affected the biofilm formation in C. albicans causing a decrease in the biofilm growth. Chemical analysis of the F(8-10) fractions detected as major active compounds, 2-hexen-1-ol, 3-hexen-1-ol and cyclodecane. Standards of these compounds tested grouped provided a stronger activity than the oil suggesting a synergistic action from the major oil constituents. The activity of C. sativum oil demonstrates its potential for a new natural antifungal formulation.

5.
Pak J Biol Sci ; 10(4): 568-74, 2007 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-19069536

RESUMO

The present research evaluated the influence of a chayotte (Sechium edule) extract (macerated) on the bioavailability of 99TcO4Na as well as in the mass of the organs. In this study, in the biodistribution analysis, the 99mTcO4Na was administrated into female Wistar rats (diabetes and no diabetes induced) which had drunk or not the extract for 7 days. After 10 min, animals were sacrificed, the organs were isolated, the radioactivity determined in a well counter and the percentages of radioactivity per gram (%ATI/g) in the organs and mass of them (g) were calculated. The analysis of the results has indicated that in the diabetes group had been an increase in the uptake of 99mTcO4Na the in pancreas as well as in the diabetes groups treated with chayotte extract. The mass of the spleen, stomach, pancreas, heart and kidney has been altered due to the comparison of the groups. It is possible to suggest that some components of chayotte extracts present an oxidant power able to alter the biodistribution of 99mTcO4Na, as a tip, we speculate that the referred extract when metabolized in the liver may produce reactive metabolites with oxidant properties linked to the stress which is generated by diabetic status, this fact could justify by the increase of %ATI/g in the pancreas which probably may be due to the producing of AGEs in diabetes status as well as by the different molecular and cellular mechanisms related to the effects of the extract and diabetes would promote differences in the mass of the organs.


Assuntos
Cucurbitaceae/química , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/radioterapia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Compostos Radiofarmacêuticos/uso terapêutico , Animais , Diabetes Mellitus Experimental/induzido quimicamente , Tamanho do Órgão/efeitos dos fármacos , Extratos Vegetais/farmacocinética , Compostos Radiofarmacêuticos/farmacocinética , Ratos , Ratos Wistar
6.
Pak J Biol Sci ; 10(5): 823-7, 2007 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-19069873

RESUMO

The use of natural products as medicines has been growing in the entire world. There are concerns that these products may contain potentially toxic ingredients and contaminants such as heavy metals. The labeling of blood constituents with technetium-99m has been influenced by the presence of natural extracts. We evaluated the influence of a chayotte (Sechium edule) extract (100% v/v macerated) on the labeling of blood elements with 99mTc. The animals were treated with the extract during 15 days. Samples of blood were carried out with specific blood biochemistry kits. The present study analyzed the influence ofchayotte in the survival of the strain of Escherichia coli AB1157 submitted to reactive oxygen species induced by stannous chloride. There was a reduction of the lethal effect induced by stannous chloride on the survival of the E. coli culture in the presence of chayotte. The results indicated a decrease in the level of glucose and globulin The effect of the extract could be explained by its metabolic transformation inducing the generation of oxidant metabolites. The culture of bacteria when was treated with stannous chloride and chayotte simultaneously, the extract could be reacting with stannous chloride ions, protecting them against the oxidation avoiding the generation of reactive oxygen species.


Assuntos
Análise Química do Sangue , Cucurbitaceae/química , Extratos Vegetais/farmacologia , Compostos de Estanho/farmacologia , Animais , Ratos , Ratos Wistar
8.
Aten Primaria ; 26(5): 323-6, 2000 Sep 30.
Artigo em Espanhol | MEDLINE | ID: mdl-11100603

RESUMO

OBJECTIVES: To study the attitude of primary care doctors when a high (> or = 4 ng/ml) prostate-specific antigen (PSA) is found and to examine the variables linked to a prostate biopsy and the diagnosis of prostate cancer (PC). DESIGN: Descriptive, observational study. SETTING: Urban health district. PATIENTS: Ninety-four men not previously diagnosed with PC who in 1998 had a PSA figure > or = 4 ng/ml. The list was obtained from the pertinent laboratory. MEASUREMENTS: The following variables were gathered from review of clinical records: family background of PC, age, PSA figure, reason for request for PSA (if not given, it was considered a screening), referral to the urologist, rectal touch, transrectal echography, prostate biopsy and final diagnosis. RESULTS: Average age was 70 (SD, 9.31). The reason for requesting PSA was: urine symptoms in 25 (26.6%), other signs or symptoms in 25 (26.6%), request of patient in 2 cases (2.1%) and screening in 42 (44.7%). Rectal touch took place in 16 cases. Twenty-nine people were referred for examination to the urologist. 36 patients had an echography and biopsy. Variables linked to the prostate biopsy in the logistic model were: higher value of the PSA (OR 1.1; 95% CI, 1.03-1.18), being older (OR 0.92; CI, 0.87-0.98) and rectal touch performed (OR 3.58; CI, 1.02-12.51). Ten cases of PC were diagnosed. CONCLUSIONS: The most common reason for a PSA request was screening. Prostate biopsy was not requested for 58 men. A primary care guide to action concerning PC diagnosis in cases of PSA > or = 4 ng/ml would be useful.


Assuntos
Atenção Primária à Saúde , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/diagnóstico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Atitude do Pessoal de Saúde , Biópsia , Humanos , Modelos Logísticos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Próstata/patologia , Neoplasias da Próstata/patologia
9.
Int J Vitam Nutr Res ; 53(3): 338-44, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6629673

RESUMO

The present study was conducted to evaluate the nutritive value of a multiple level rice and bean diet fed to migrant workers. Nine healthy males, 18 to 28 years old were admitted to our metabolic unit for a three period metabolic balance study. The rice and beans based diet was fed at levels to provide 0.4, 0.6 or 0.8 g of protein/kg body weight. Mean energy intake for the three levels of intake and for all subjects was 46.9 +/- 2.9 kcal/kg Bwt/day. Each nitrogen balance period consisted of a) one day on a nitrogen free diet b) five days on an adaptation period, and c) five days on the balance period. "True digestibility', "true nitrogen balance", biologic value, and net protein utilization (NPU) were calculated. Mean protein requirements were estimated by regression analysis of pooled data of balances at different levels of intake. These results showed values of 103.8 mg N/kg Bwt/day. Mean and standard deviation for protein digestibility at each level of intake were 69.2 +/- 17.0, 75.5 +/- 5.3, and 74.9 +/- 10.6% respectively. Mean and standard deviation for NPU were 49.9 +/- 26.3, 55.6 +/- 10.6, and 57.8 +/- 14.4 respectively. The data support the conclusion that a rice and bean diet is a well balanced food combination and can serve as a fairly good source of protein for the adult human.


Assuntos
Proteínas Alimentares/administração & dosagem , Fabaceae , Oryza , Plantas Medicinais , Adolescente , Adulto , Brasil , Ingestão de Energia , Humanos , Masculino , Nitrogênio/administração & dosagem , Necessidades Nutricionais , Valor Nutritivo , Saúde da População Rural
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