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991.
Phenolic endocrine disrupting chemicals are environmental pollutants with xenostrogen effects in wildlife and humans. The aim of this study was to determine 4-nonylphenol, Octylphenol, and Bisphenol A residues in various tissues of carp fish samples from Anzali wetland, Iran. 4-NP, OP, and BPA were detected with GC–MS in the muscle of fish from sampling location with maximal concentrations of 8.17, 9.67 and 5.87 μg/gdw, respectively. The highest concentrations of these compounds were found in the liver by HPLC. Since many endocrine disrupting substances were significantly lipophilic, distributing of these compounds into fish tissue has been correlated with lipid content.  相似文献   
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The aim of this work was to optimize the encapsulation of a third generation bisphosphonate (risedronate sodium RS) into polylactide-co-glycolide (PLGA) microspheres using a double emulsion technique for implant purposes. Microspheres were prepared by w/o/w double emulsion technique using PLGA in the ratio of 50:50 and 75:25. Critical process parameters namely: polymer type and amount, drug amount and internal aqueous phase volume ratio were evaluated for their effect on entrapment efficiency (EE%) of RS. Microspheres were characterized for their entrapment efficiency, morphology and particle size by UV spectrophotometry, scanning electron microscopy, and laser diffraction respectively. A 24 full factorial design was used for model production. High EE% exceeding 80% were obtained through the manipulation of the previously mentioned factors. Microparticles showed smooth surface with few pores and a size ranging from 1-6 µm. The factorial mathematical model was validated by check point analysis revealing good agreement between actual and predicted values. PLGA microspheres successfully encapsulated RS at high levels with suitable size and morphology suggesting their potential use in the treatment of bone diseases as injectable implants.  相似文献   
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The hand motor hot spot (hMHS) is one of the most salient parameters in transcranial magnetic stimulation (TMS) practice, notably used for targeting. It is commonly accepted that the hMHS corresponds to the hand representation within the primary motor cortex (M1). Anatomical and imaging studies locate this representation in a region of the central sulcus called the “hand knob”. The aim of this study was to determine if the hMHS location corresponds to its expected location at the hand knob. Twelve healthy volunteers and eleven patients with chronic neuropathic pain of various origins, but not related to a brain lesion, were enrolled. Morphological magnetic resonance imaging of the brain was normal in all participants. Both hemispheres were studied in all participants except four (two patients and two healthy subjects). Cortical mapping of the hand motor area was conducted using a TMS-dedicated navigation system and recording motor evoked potentials (MEPs) in the contralateral first dorsal interosseous (FDI) muscle. We then determined the anatomical position of the hMHS, defined as the stimulation site providing the largest FDI-MEPs. In 45 % of hemispheres of normal subjects and 25 % of hemispheres of pain patients, the hMHS was located over the central sulcus, most frequently at the level of the hand knob. However, in the other cases, the hMHS was located outside M1, most frequently anteriorly over the precentral or middle frontal gyrus. This study shows that the hMHS does not always correspond to the hand knob and M1 location in healthy subjects or patients. Therefore, image-guided navigation is needed to improve the anatomical accuracy of TMS targeting, even for M1.  相似文献   
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Imatinib is a principal therapeutic agent for targeting colorectal tumours. However, mono‐targeting by imatinib does not always achieve complete cancer eradication. Selenite, a well‐known chemopreventive agent, is commonly used in cancer patients. In this study, we aimed to explore whether selenite can modulate imatinib cytotoxicity in colorectal cancer cells. HCT116 cells were treated with different concentrations of imatinib and/or selenite for 24, 48 and 72 hr. Imatinib–selenite interaction was analysed using isobologram equation. As indicators of apoptosis, DNA fragmentation, caspase‐3 activity, Bcl‐2 expression were explored. Autophagic machinery was also checked by visualizing acidic vesicular organelles and measuring Beclin‐1 expression. Furthermore, reactive oxygen and nitrogen species were also examined. This study demonstrated that selenite synergistically augmented imatinib cytotoxicity in HCT116 cells as demonstrated by combination and dose reduction indices. Supranutritional dose of selenite when combined with imatinib induced apoptotic machinery by decreasing Bcl‐2 expression, increasing caspase‐3 activity and subsequently fragmenting DNA and blunted cytoprotective autophagy by decreasing Beclin‐1 expression and autophagosomes formation. Moreover, their combination induced cell cycle S‐phase block, increased total thiol content and reduced nitric oxide levels. In conclusion, selenite synergizes imatinib cytotoxicity through multi‐barrelled molecular targeting, providing a novel therapeutic approach for colorectal cancer.  相似文献   
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