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81.
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Journal of Autism and Developmental Disorders - Atypical eating behaviors displayed by children with autism spectrum disorder (ASD) predispose them to unhealthy weight gain. We determined the...  相似文献   
83.
In humans, the offspring of maternal cocaine misusers are known to have subtle cognitive and motor impairments in later life. It was therefore hypothesized that such exposure in animals would also affect the morphological structure of the brain. This possibility was investigated by exposing rats to cocaine between embryonic day 15 and postnatal day 6. Samples of the cocaine-exposed and control rats were killed for examination at 22 and 150 postnatal days of age. Stereological procedures (the Cavalieri principle together with the physical disector method) were utilized to estimate the total number of pyramidal and granule cells in defined regions of the hippocampal formation. At 22 days of age, the control offspring had about 373 000 pyramidal cells whereas the cocaine-treated animals only had about 310,000 cells in the CA1 + CA2 + CA3 region. By 150 days of age the values were about 396,000 and 348,000, respectively. The differences between age-matched groups were statistically significant. There were about 626,000 and 687,000 dentate gyrus granule cells in the 22-day-old control and cocaine-treated groups, respectively. By postnatal day 150 the control rats had about 832,000 granule cells whilst the cocaine-treated rats had about 693,000. There was a significant main effect of age as well as group-age interaction in this measure. These results show that even moderate exposure to cocaine during the late gestation and early postnatal period in rats is a potent teratogen and can markedly influence the development of neurons in the hippocampal formation.  相似文献   
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Bergenin and menisdaurin are biologically active components which are found in plant Flueggea virosa (Phyllanthaceae). Bergenin has pharmacological actions such as chemopreventive and antihepatotoxic while menisdaurin has an anti-viral activity which needs its evaluation by an analytical method (UPLC-PDA method) that can be applied to the quality control of pharmaceutical preparations. The developed UPLC-PDA method was applied for identification and quantification of standards bergenin and menisdaurin in the methanol extract of F. virosa (FVME). The analysis was carried out using Eclipse C18 (4.6?×?100?mm, 3.5?µm) UPLC column. The optimized chromatographic condition was achieved at 0.16?mL/min flow rate using gradient system with acetonitrile and water as mobile phase. Both biomarkers were measured at λmax 235?nm in PDA detector at ambient temperature. The developed method furnished sharp and intense peaks of menisdaurin and bergenin at Rt?=?2.723 and 3.068?min, respectively along with r2?>?0.99 for both. The recoveries of bergenin and menisdaurin were found in the range of 99.37–101.49% and 98.20–100.08%, respectively. With other validation data, including precision, specificity, accuracy, and robustness, this method demonstrated excellent reliability and sensitivity. The separation parameters i.e. retention, separation, and resolution factors for resolved standards (bergenin and menisdaurin) were >1, which showed good separation. The quantity of bergenin and menisdaurin in the FVME sample was found as 15.16 and 3.28% w/w, respectively. The developed UPLC-PDA method could be conveniently adopted for the routine quality control analysis.  相似文献   
86.
Context: Eurycoma longifolia Jack (Simaroubaceae) commonly known as Tongkat Ali is one of the most important plants in Malaysia. The plant extracts (particularly roots) are widely used for the treatment of cough and fever besides having antimalarial, antidiabetic, anticancer and aphrodisiac activities.

Objectives: This study assesses the extent of adulteration of E. longifolia herbal medicinal products (HMPs) using DNA barcoding validated by HPLC analysis.

Materials and methods: Chloroplastic rbcL and nuclear ITS2 barcode regions were used in the present study. The sequences generated from E. longifolia HMPs were compared to sequences in the GenBank using MEGABLAST to verify their taxonomic identity. These results were verified by neighbor-joining tree analysis in which branches of unknown specimen are compared to the reference sequences established from this study and other retrieved from the GenBank. The HMPs were also analysed using HPLC analysis for the presence of eurycomanone bioactive marker.

Results: Identification using DNA barcoding revealed that 37% of the tested HMPs were authentic while 27% were adulterated with the ITS2 barcode region proven to be the ideal marker. The validation of the authenticity using HPLC analysis showed a situation in which a species which was identified as authentic was found not to contain the expected chemical compound.

Discussion and conclusions: DNA barcoding should be used as the first screening step for testing of HMPs raw materials. However, integration of DNA barcoding with HPLC analysis will help to provide detailed knowledge about the safety and efficacy of the HMPs.  相似文献   

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Purpose

The aim of the present study was to formulate and optimize lipid blend-based olmesartan medoxomil (OLM) loaded nanoparticulate scaffolds (NLCs) for enhanced oral bioavailability.

Method

The OLM-NLCs were formulated using dependent variables in different concentrations of solid lipid, liquid lipid, surfactant, and co-surfactant by using melt emulsification combined with ultrasonication technique. The formulations were experimentally optimized using a three-factor, three-level statistical design approach. The formulated OLM-NLCs were evaluated for various pharmaceutical quality evaluation parameters and further optimized formulation (OLM-NLCopt) was assessed for release kinetics, thermal behavior, and in vivo absorption assessment.

Result

The optimized formulation (OLM-NLCopt) showed particle size (138.7 nm), PDI (0.18), and entrapment efficiency (83.65%). The comparative in vitro release study revealed OLM-NLCopt showed significantly higher (p?<?0.05) drug release compare to OLM-susp. The in vivo study showed the OLM-NLCopt indicated nearly 3-fold improvement in oral bioavailability vis-a-vis OLM-susp in mice model.

Conclusion

The results of the release study and pharmacokinetic study suggest the potential of OLM-NLCs for improved oral delivery.
  相似文献   
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This study was designed to test the pre-treatment doses of guggulipid (50?mg/kg), aspirin (100?mg/kg) per orally and co-administration of both drugs for 28 days followed by middle cerebral artery occlusion – a model of focal cerebral ischemia in rats. Middle cerebral artery was occluded for two hours, followed by reperfusion for 22 hours for the induction of focal cerebral ischemia in rats. Neurobehavioral tests like locomotor activity and grip strength tests were performed before sacrificing the animal. After neurobehavioral tests, the animals were sacrificed for the measurement of infarction areas and biochemical estimations in brain. Locomotor activity and grip strength were significantly improved in guggulipid and aspirin pre-treated rats. Guggulipid and aspirin pre-treatment reduced the infarction areas as compared with middle cerebral occluded (MCAO) rats. An elevation of nitrite, thiobarbituric acid reactive substance (TBARS), acetylcholine esterase activity (AchE) and reduction in antioxidant enzymes like superoxide dismutase (SOD), glutathione (GSH) and catalase were observed following MCAO. Pre-treatment with guggulipid and aspirin caused a reduction in TBARS and nitrite levels, AchE, but elevated GSH level, SOD and catalase activities as compared with MCAO rats. The protective effects observed in this study were due to antioxidant, anti-inflammatory and anti-hyperlipidemic properties of guggulipid. The protective effect of guggulipid in cerebral ischemia, that it may have a role in reversing the symptoms and may offer significant neuroprotection in stroke.  相似文献   
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