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371.
We aimed to investigate the effect of maternal exposure to NaF on mandibular bone microarchitecture and phosphocalcic plasma parameters of the offspring. For this purpose, 10-, 15-, and 21-day-old pups (n?=?6–8 per group) from two groups of mothers, control and NaF 50mg/L treated dams, were used. Plasma calcium (Ca) and phosphorus (P) levels and alkaline phosphatase activity (ALP) were measured. Fluoride concentration (F?) in bone and in stomach content was measured using potentiometry after isothermal distillation. Morphometric, histological, and histomorphometric analyses of the jaw bones were performed. Plasma Ca and P levels and ALP activity increased in 10-day and decreased in 21-day-old pups from NaF-treated mothers. Fluoride concentration in stomach content samples of 15- and 21-day-old nursing pups from mothers exposed to NaF in their drinking water was higher compared to that observed in control dam offspring. Mandibular F? content was higher in 21-day-old pups born to F?-exposed dams compared to those observed in age-matched control pups. Mandibular area increased in 21-day-old pups born to treated mothers as compared to controls. Mandibular bone volume BV/TV (%) was higher in offspring from NaF-exposed dams than in controls at all the studied times. The increase in bone volume after exposure to F? was concomitant with the increase in trabecular thickness and the decrease in trabecular separation. Altogether, our results showed that exposure to NaF during gestation and lactation increased mandibular area and bone volume of pups, with concomitant changes in phosphocalcic parameters associated with the bone modeling process.  相似文献   
372.
There have been few investigations of trace elements in the urine and hair of populations exposed to high levels of arsenic (As) in drinking water. Therefore, concentrations of selected metals in urine and hair samples from a population in a study area where arsenism was endemic and a control area were determined. It was found that the median concentrations of barium (Ba), cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), molybdenum (Mo), nickel (Ni), lead (Pb), zinc (Zn), and As in the urine samples from the population in the study area were 3.87, 0.47, 0.50, 61.84, 26.82, 1.33, 128.45, 7.05, 1.10, 233.75, and 339.63 μg/L, respectively. The corresponding values in the urine samples from a population in the control area were 29.08, 0.19, 0.21, 27.77, 10.32, 4.61, 14.01, 2.19, 3.90, 113.92, and 20.28 μg/L, respectively. In the study area, Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, and Zn excreted in the urine were likely to be mainly derived from drinking water with high levels of arsenic. The median concentrations of Ba, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Zn, and As in the hair samples from the study area were 4.16, 0.03, 0.09, 1.09, 6.54, 1.97, 0.06, 0.53, 1.64, 144.28, and 1.67 mg/kg, respectively. The corresponding values from the control area were 4.76, 0.03, 0.02, 1.41, 8.31, 1.34, 0.07, 0.39, 0.86, 154.58, and 0.29 mg/kg, respectively. Significant positive correlations were observed between As and Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, and Zn in the urine in the study area. However, As was not positively associated with these metals in the hair samples. Exposure to high levels of As in drinking water increased the accumulation of Ba and Mn in the hair and the excretion of Cd, Cu, and Mo in the urine in the study area. The population in the study area might experience Cu and Mo deficiencies for an increasing excretion of Cu and Mo.  相似文献   
373.
Ficus carica L. is one of the oldest trees belonging to the mulberry family. It has both nutritional and medicinal benefits, as it is a source of potential bioactive compounds. Fig leaves were collected at four maturation stages, to evaluate the variation in polyphenolic compounds, antioxidant activity, and different pigments level. Polyphenols were identified using HPLC–DAD. Different pigments level, total phenolic contents, and radical scavenging activity were quantified. The HPLC analysis revealed the presence of fourteen polyphenolic compounds in the fig leaves. Quercetin-3-glucoside, caftaric acid, quercetin-3, 7-diglucoside, and coumaroyl-hexose were the major phenolic compounds. Kaempferol-3-O-sophorotrioside, cichoric acid and sinapic acid glucoside were identified for the first time. Significant quantitative changes were observed during maturation, particularly in polyphenolic compounds. There were significant changes in pigments level, total phenolic contents, and radical scavenging activity. It was observed that fig leaves are a rich source of polyphenolic compounds during all stages of maturation.  相似文献   
374.
375.
The use of natural remedies and pharmacological mineral supplements for liver disease treatment has a long history. In present study, the levels of selenium (Se) and zinc (Zn) were determined in biological samples (serum and whole blood) of female hepatitis C patients (n?=?132), age ranged 30–45 years, before and after 30 days treatment with herbal/pharmaceutical supplements. For comparative study, 128 age-matched female subjects, residing in the same residential areas and have socioeconomic status, were selected as referents. The Se and Zn in supplements, blood, and sera were determined by atomic absorption spectrometry. It was observed that Zn and Se in blood and serum samples of viral hepatitis C (HCV) patients were reduced in the range of 28.6–39 % and 24–36 %, respectively, as compared to those of referents. After herbal/pharmaceutical supplementations, 20.6–25.0 and 9.15–13.2 % of Zn and 10.6–12.1 and 19.6–21.4 % of Se were enhanced in sera and blood samples of HCV patients, respectively. The resulted data indicated that the levels of Se and Zn in addition to some biochemical parameters were improved in HCV patients after herbal/pharmaceutical supplementation. The effects of both supplements were not significantly different (p?>?0.05).  相似文献   
376.
In present study, lead (Pb) level in biological samples of children with physiological disorders (liver, bone, and gastrointestinal; age ranged 1–10 years) have been assessed. For comparison purpose, age-matched healthy children were also selected. Cloud point extraction (CPE) was employed for preconcentration of Pb in acid-digested biological samples prior to its determination by flame atomic absorption spectrometry (FAAS). Dithizone (diphenylthiocarbazone) and nonionic surfactant Triton X-114 (TX-114) were used as complexing reagent and extractant, respectively. The effects of several experimental variables on proposed CPE were evaluated. Under the optimum experimental conditions, the observed detection limit (LOD) and the enhancement factor (EF) were 0.08 μg L?1 and 53, respectively. Relative standard deviation (RSD) of 10 μg L?1 Pb was 3.4 %. It was observed that children with liver-, bone-, and gastrointestinal-related disorders had three- to fourfold higher Pb level in blood and scalp hair samples.  相似文献   
377.
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379.
Bacillus thuringiensis is an insecticidal bacterium whose chitinolytic system has been exploited to improve insect resistance in crops. In the present study, we studied the CBP24 from B. thuringiensis using homology modeling and molecular docking. The primary and secondary structure analyses showed CBP24 is a positively charged protein and contains single domain that belongs to family CBM33. The 3D model after refinement was used to explore the chitin binding characteristics of CBP24 using AUTODOCK. The docking analyses have shown that the surface exposed hydrophilic amino acid residues Thr-103, Lys-112 and Ser-162 interact with substrate through H-bonding. While, the amino acids resides Glu-39, Tyr-46, Ser-104 and Asn-109 were shown to have polar interactions with the substrate. The binding energy values evaluation of docking depicts a stable intermolecular conformation of the docked complex. The functional characterization of the CBP24 will elucidate the substrate-interaction pathway of the protein in specific and the carbohydrate binding proteins in general leading towards the exploration and exploitation of the prokaryotic substrate utilization pathways.  相似文献   
380.
This paper presents an in silico characterization of the chitin binding protein CBP50 from B. thuringiensis serovar konkukian S4 through homology modeling and molecular docking. The CBP50 has shown a modular structure containing an N-terminal CBM33 domain, two consecutive fibronectin-III (Fn-III) like domains and a C-terminal CBM5 domain. The protein presented a unique modular structure which could not be modeled using ordinary procedures. So, domain wise modeling using MODELLER and docking analyses using Autodock Vina were performed. The best conformation for each domain was selected using standard procedure. It was revealed that four amino acid residues Glu-71, Ser-74, Glu-76 and Gln-90 from N-terminal domain are involved in protein-substrate interaction. Similarly, amino acid residues Trp-20, Asn-21, Ser-23 and Val-30 of Fn-III like domains and Glu-15, Ala-17, Ser-18 and Leu-35 of C-terminal domain were involved in substrate binding. Site-directed mutagenesis of these proposed amino acid residues in future will elucidate the key amino acids involved in chitin binding activity of CBP50 protein.  相似文献   
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