The thyroid, an endocrine gland located at the base of the neck, produces thyroid hormones (triiodothyronine (T3) and thyroxine (T4)). The production of these hormones is possible by iodine and other nutrients such as...The thyroid, an endocrine gland located at the base of the neck, produces thyroid hormones (triiodothyronine (T3) and thyroxine (T4)). The production of these hormones is possible by iodine and other nutrients such as selenium and certain vitamins. To assess the thyroid disturbances in the mountain population of Benin, a survey was conducted in Natitingou, a mountain town located in the department of Atacora, in the northwest of Benin, on a sample of thirty (30) adults (15 men and 15 women), most of whom are educated. The results of the questionnaire revealed that 43% of the surveyed population acknowledged having knowledge on the mentioned subject and have dietary habits based on the consumption of seafood, and also legumes (20%). The examination of the serum results of the dosage of T3, T4 and TSH hormones revealed cases of thyroid disturbances in the region (36.32% in men and 44.98% in women). The analysis of a comparative table including the “VEDALAB Easy Reader+” and five (05) other readers, presents the performance, reading techniques, principles, advantages and disadvantages of each device. Pending further studies, some recommendations were made at the end of this study to the academic authorities regarding probable cases of dysthyroidism for which additional examinations are required and an awareness for the improvement of dietary habits.展开更多
From the Asteraceaes family, <i>Tridax procumbens</i> is a wild species frequently found in fields, meadows and roadsides. It is traditionally used to treat yellow fever, typhoid fever, high blood pressure...From the Asteraceaes family, <i>Tridax procumbens</i> is a wild species frequently found in fields, meadows and roadsides. It is traditionally used to treat yellow fever, typhoid fever, high blood pressure and diabetes. In this work we used the hydro-ethanolic extract of the leaves and stems of the plant and also the fractions of this extract to determine the preventive and therapeutic activities of the plant against obesity, hyperglycemia and hyperlipidemia. The yields of the fractions obtained by decantation of the hydro-ethanolic extract are respectively 0.160% with hexane, 0.073% with dichloromethane, 0.09% with diethyl ether and 0.150% with ethyl acetate. Hyperglycemia and hyperlipidemia were induced in the rats submitted to a fatty and sweet diet for 28 days. Our results showed a significant increase in glycemia, weight and triglyceride level in rats that were subjected to the diet. On the other hand, the rats treated with the dose of 500 mg/kg of body weight of <i>Tridax procumbens</i> extract during the induction showed a reduction in weight gain and an absence of increase <span style="letter-spacing:-0.1pt;">in blood sugar and triglyceride levels. The ethyl acetate fraction of <i>Tridax pro</i></span><i>cumbens</i> extract administered to fatty and hyperglycemic rats at 50 mg/kg of body weight for 14 days did not induce change in the blood sugar and triglycerides level of fatty and hyperglycemic rats. If it seems obvious that the extract of <i>Tridax procumbens</i> prevents hyperglycemia and hyperlipidemia, the ethyl acetate fraction does not seem to have a therapeutic effect.展开更多
Polymerized liposomes encapsulating L-tryptophan were studied with the aim to characterize them as drug delivery systems for the treatment of several metabolic diseases that need an increased systemic L-tryptophan con...Polymerized liposomes encapsulating L-tryptophan were studied with the aim to characterize them as drug delivery systems for the treatment of several metabolic diseases that need an increased systemic L-tryptophan concentration. polymerized liposomes were obtained by UV irradiation of vesicles containing 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DC8,9PC) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) in a 1:1 molar ratio, in the presence of 10 and 50 mol% of L-tryptophan (respect to total lipid concentration). Polymerization efficiency was studied spectrophotometrically. Also, bilayer packing at the polar head region was followed with the Merocyanine 540 (MC540) and specific interactions in the lipopolymers were studied by FTIR. High L-tryptophan concentrations (50 mol% respect to total lipid concentration) induced a higher amount of six- and nine-unit polymers. This phenomenon was induced because the L-tryptophan located outside the lipid membrane was included in it during the polymerization process and was thus responsible for the better accommodate of the polar head region. This was not possible with the lower amount of L-tryptophan (10 mol%). The stability of lipopolymers with different amounts of L-tryptophan was studied through release profiles. Polymerized liposomes with 50 mol% of L-tryptophan were able to retain around 80% of the amino acid after 24 hours, whereas those with 10 mol % of the amino acid were able to retain 20%. The metabolic activity of the Caco-2 cell line was also studied. Cytotoxic effects were low in the presence of polymerized liposomes, rendering a maximum percentage of cell death of 30%. In summary, this work stresses the relevance of nonspecific drug-polymerized membrane binding on L-tryptophan pharmacological interaction with possible pharmaceutical applications in liposomal drug delivery. Moreover, the absence of significant cytotoxic effects allows the system proposed to be applied in human health.展开更多
Histidine coordinated to Chl a is a distinct characteristic of Chl a in vivo. By usinghistidine analogue of 1-methylimidazole (C4H6N2) and measuring the UV/vis absorption, CD and MCD spectra of the interaction between...Histidine coordinated to Chl a is a distinct characteristic of Chl a in vivo. By usinghistidine analogue of 1-methylimidazole (C4H6N2) and measuring the UV/vis absorption, CD and MCD spectra of the interaction between C4H6N2and Chl a in CCI4, we have obtained that: (i) In pure CCI4 solvent, Chl a molecule is in five-coordinate state, and two Chl a molecules form an asymmetric compact-dimer with strong coupling interaction. We propose that the two Chl a molecules are connected by two unequally coordinated Mg-O bonds (the two oxygen atoms come from the C=O of C131 keto and C17 ester, respectively); (ii) when the molar ratio of C4H6N2/Chl a is 0.5 or 1 (corresponding to 2Chl a #1C4H6N2 and 2Chl a ·2C4H6N2, respectively), significant changes have been observed in the absorption, CD and MCD spectra, which indicate that the Chl a remains in dimer form, but the coupling interaction between them reduces greatly. We postulate that C4H6N2 replaces the ligation of C=O of C17 ester and C131 keto to Mg atoms展开更多
文摘The thyroid, an endocrine gland located at the base of the neck, produces thyroid hormones (triiodothyronine (T3) and thyroxine (T4)). The production of these hormones is possible by iodine and other nutrients such as selenium and certain vitamins. To assess the thyroid disturbances in the mountain population of Benin, a survey was conducted in Natitingou, a mountain town located in the department of Atacora, in the northwest of Benin, on a sample of thirty (30) adults (15 men and 15 women), most of whom are educated. The results of the questionnaire revealed that 43% of the surveyed population acknowledged having knowledge on the mentioned subject and have dietary habits based on the consumption of seafood, and also legumes (20%). The examination of the serum results of the dosage of T3, T4 and TSH hormones revealed cases of thyroid disturbances in the region (36.32% in men and 44.98% in women). The analysis of a comparative table including the “VEDALAB Easy Reader+” and five (05) other readers, presents the performance, reading techniques, principles, advantages and disadvantages of each device. Pending further studies, some recommendations were made at the end of this study to the academic authorities regarding probable cases of dysthyroidism for which additional examinations are required and an awareness for the improvement of dietary habits.
文摘From the Asteraceaes family, <i>Tridax procumbens</i> is a wild species frequently found in fields, meadows and roadsides. It is traditionally used to treat yellow fever, typhoid fever, high blood pressure and diabetes. In this work we used the hydro-ethanolic extract of the leaves and stems of the plant and also the fractions of this extract to determine the preventive and therapeutic activities of the plant against obesity, hyperglycemia and hyperlipidemia. The yields of the fractions obtained by decantation of the hydro-ethanolic extract are respectively 0.160% with hexane, 0.073% with dichloromethane, 0.09% with diethyl ether and 0.150% with ethyl acetate. Hyperglycemia and hyperlipidemia were induced in the rats submitted to a fatty and sweet diet for 28 days. Our results showed a significant increase in glycemia, weight and triglyceride level in rats that were subjected to the diet. On the other hand, the rats treated with the dose of 500 mg/kg of body weight of <i>Tridax procumbens</i> extract during the induction showed a reduction in weight gain and an absence of increase <span style="letter-spacing:-0.1pt;">in blood sugar and triglyceride levels. The ethyl acetate fraction of <i>Tridax pro</i></span><i>cumbens</i> extract administered to fatty and hyperglycemic rats at 50 mg/kg of body weight for 14 days did not induce change in the blood sugar and triglycerides level of fatty and hyperglycemic rats. If it seems obvious that the extract of <i>Tridax procumbens</i> prevents hyperglycemia and hyperlipidemia, the ethyl acetate fraction does not seem to have a therapeutic effect.
文摘Polymerized liposomes encapsulating L-tryptophan were studied with the aim to characterize them as drug delivery systems for the treatment of several metabolic diseases that need an increased systemic L-tryptophan concentration. polymerized liposomes were obtained by UV irradiation of vesicles containing 1,2-bis(10,12-tricosadiynoyl)-sn-glycero-3-phosphocholine (DC8,9PC) and 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) in a 1:1 molar ratio, in the presence of 10 and 50 mol% of L-tryptophan (respect to total lipid concentration). Polymerization efficiency was studied spectrophotometrically. Also, bilayer packing at the polar head region was followed with the Merocyanine 540 (MC540) and specific interactions in the lipopolymers were studied by FTIR. High L-tryptophan concentrations (50 mol% respect to total lipid concentration) induced a higher amount of six- and nine-unit polymers. This phenomenon was induced because the L-tryptophan located outside the lipid membrane was included in it during the polymerization process and was thus responsible for the better accommodate of the polar head region. This was not possible with the lower amount of L-tryptophan (10 mol%). The stability of lipopolymers with different amounts of L-tryptophan was studied through release profiles. Polymerized liposomes with 50 mol% of L-tryptophan were able to retain around 80% of the amino acid after 24 hours, whereas those with 10 mol % of the amino acid were able to retain 20%. The metabolic activity of the Caco-2 cell line was also studied. Cytotoxic effects were low in the presence of polymerized liposomes, rendering a maximum percentage of cell death of 30%. In summary, this work stresses the relevance of nonspecific drug-polymerized membrane binding on L-tryptophan pharmacological interaction with possible pharmaceutical applications in liposomal drug delivery. Moreover, the absence of significant cytotoxic effects allows the system proposed to be applied in human health.
文摘Histidine coordinated to Chl a is a distinct characteristic of Chl a in vivo. By usinghistidine analogue of 1-methylimidazole (C4H6N2) and measuring the UV/vis absorption, CD and MCD spectra of the interaction between C4H6N2and Chl a in CCI4, we have obtained that: (i) In pure CCI4 solvent, Chl a molecule is in five-coordinate state, and two Chl a molecules form an asymmetric compact-dimer with strong coupling interaction. We propose that the two Chl a molecules are connected by two unequally coordinated Mg-O bonds (the two oxygen atoms come from the C=O of C131 keto and C17 ester, respectively); (ii) when the molar ratio of C4H6N2/Chl a is 0.5 or 1 (corresponding to 2Chl a #1C4H6N2 and 2Chl a ·2C4H6N2, respectively), significant changes have been observed in the absorption, CD and MCD spectra, which indicate that the Chl a remains in dimer form, but the coupling interaction between them reduces greatly. We postulate that C4H6N2 replaces the ligation of C=O of C17 ester and C131 keto to Mg atoms