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1.
In light of the pharmacophoric structural requirements for achieving anticonvulsant activity, a series of N-(1-methyl-4-oxo-2-un/substituted-1,2-dihydroquinazolin-3[4H]-yl)benzamide (4a-g) and N-(1-methyl-4-oxo-2-un/substituted-1,2-dihydroquinazolin-3[4H]-yl)-2-phenylacetamide (4h-n) derivatives were synthesized in two steps starting from the reaction of N-methyl isatoic anhydride with the appropriate hydrazide and followed by condensation with the appropriate aldehyde. The anticonvulsant activities of the synthesized compounds were evaluated according to the anticonvulsant drug development (ADD) programme protocol. Among the synthesized compounds, 4n showed promising activity in both the maximal electroshock (MES) and pentylenetetrazole (PTZ) tests with median effective dose (ED50) values of 40.7 and 6 mg/kg, respectively. The six most promising derivatives, 4b , 4a , 4c , 4f , 4j , and 4i , showed very low ED50 values in the PTZ test (3.1, 4.96, 8.68, 9.89, 12, and 13.53 mg/kg, respectively). All the tested compounds showed no to low neurotoxicity in the rotarod test with a wide therapeutic index. Docking studies of compound 4n suggested that GABAA binding could be the mechanism of action of these derivatives. The in silico drug likeliness parameters indicated that none of the designed compounds violate Lipinski's rule of five and that they are able to cross the blood–brain barrier.
Hit, Lead & Candidate Discovery
  相似文献   
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We study the image formation of vibro-acoustography systems based on a concave sector array transducer taking into account depth-of-field effects. The system point-spread function (PSF) is defined in terms of the acoustic emission of a point-target in response to the dynamic radiation stress of ultrasound. The PSF on the focal plane and the axis of the transducer are presented. To extend the obtained PSF to the 3D-space, we assume it is a separable function in the axial direction and the focal plane of the transducer. In this model, an image is formed through the 3D convolution of the PSF with an object function. Experimental vibro-acoustography images of a breast phantom with lesion-like inclusions were compared with simulated images. Results show that the experimental images are in good agreement with the proposed model.  相似文献   
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Cell lines derived from tumors contain numerous chromosomal aberrations and are the focus of study in tumor evolution. The ovarian teratocarcinoma cell line PA-1 demonstrates a single chromosomal aberration: a reciprocal t(15;20)(p11.2;q11.2). A complete molecular genetic analysis was undertaken to characterize this cell line. The PA-1 cell line was studied with fluorescence in situ hybridization (FISH), spectral karyotyping (SKY), bacterial artificial chromosome (BAC) microarray, and Western blotting. Amplification of 20q is frequently implicated in both breast and ovarian cancer; this region contains a number of oncogenes including MDM2, ZNF217, and the ovarian tumor marker WFDC2 (alias HE4). FISH revealed gene amplification of AIB1 (now known as NCOA3) but not STK15 (now known as AURKA). Immunoblot analysis demonstrated 3.6-fold overexpression of the AIB1 protein product, but no elevation of the STK15. BAC cancer gene microarray analysis showed gene amplification of > or =1.20 for five oncogenes. The presence of a consistent single change in PA-1, the t(15;20)(p11.2;q11.2), suggests that the aberration is significant with respect to the transformation status of the cell line. This translocation appears to cause overexpression of AIB1 (and perhaps other proteins), which may provide an immortalizing effect on this cell line.  相似文献   
4.
Intestinal iron transport requires an iron importer (Dmt1) and an iron exporter (Fpn1). The hormone hepcidin regulates iron absorption by modulating Fpn1 protein levels on the basolateral surface of duodenal enterocytes. In the genetic, iron-loading disorder hereditary hemochromatosis (HH), hepcidin production is low and Fpn1 protein expression is elevated. High Fpn1-mediated iron export depletes intracellular iron, causing a paradoxical increase in Dmt1-mediated iron import. Increased activity of both transporters causes excessive iron absorption, thus initiating body iron loading. Logically then, silencing of intestinal Dmt1 or Fpn1 could be an effective therapeutic intervention in HH. It was previously established that Dmt1 knock down prevented iron-loading in weanling Hamp (encoding hepcidin) KO mice (modeling type 2B HH). Here, we tested the hypothesis that Dmt1 silencing combined with dietary iron restriction (which may be recommended for HH patients) will mitigate iron loading once already established. Accordingly, adult Hamp KO mice were switched to a low-iron (LFe) diet and (non-toxic) folic acid-coupled, ginger nanoparticle-derived lipid vectors (FA-GDLVs) were used to deliver negative-control (NC) or Dmt1 siRNA by oral, intragastric gavage daily for 21 days. The LFe diet reduced body iron burden, and experimental interventions potentiated iron losses. For example, Dmt1 siRNA treatment suppressed duodenal Dmt1 mRNA expression (by ~50%) and reduced serum and liver non-heme iron levels (by ~60% and >85%, respectively). Interestingly, some iron-related parameters were repressed similarly by FA-GDLVs carrying either siRNA, including 59Fe (as FeCl3) absorption (~20% lower), pancreatic non-heme iron (reduced by ~65%), and serum ferritin (decreased 40–50%). Ginger may thus contain bioactive lipids that also influence iron homeostasis. In conclusion, the combinatorial approach of FA-GDLV and Dmt1 siRNA treatment, with dietary iron restriction, mitigated pre-existing iron overload in a murine model of HH.  相似文献   
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Metformin (Met) has been shown to have pleiotropic effects such as neuroprotective, antioxidant, and anti‐inflammatory properties making that a potential candidate for the treatment of central nervous system (CNS) disorders. This study was designed to investigate the possible effect of Met on the d ‐galactose (d ‐gal)‐induced aging in ovariectomized mice. The female mice underwent bilateral ovariectomy. d ‐gal was administered orally at a dose of 500 mg/kg, and Met was administrated orally at doses of 1 and 10 mg/kg for 6 weeks. Anxiety‐like behavior was evaluated by the elevated plus‐maze. Physical power was assessed by vertical grid holding test and forced swimming capacity test. The brains were assessed for the level of superoxide dismutase (SOD) and brain‐derived neurotrophic factor (BDNF). Ovariectomy caused anxiety and declined the physical power as well as BDNF and SOD levels. d ‐gal administration in ovariectomized mice exacerbated these deleterious effects. Met hampered the anxiety‐like behavior and strengthened the physical power of d ‐gal‐treated ovariectomized mice. Met also increased the SOD and BDNF levels in the brains of d ‐gal‐treated ovariectomized animals. Based on the obtained results, we suggest Met administration as a novel therapeutic approach for the treatment of age‐related conditions in the absence of female sex hormones.  相似文献   
7.
Ultrasound bladder vibrometry (UBV) parameters have been shown in previous studies to strongly correlate with measurements from urodynamic studies. Just like urodynamic studies, UBV can be performed in supine and sitting positions. The objective of this study is to compare UBV parameters obtained in the two different positions using statistical methods. We recruited eight volunteers with healthy bladders for this purpose. The elasticity, group velocity squared and thickness of the bladder were the UBV parameters of interest, and their values were recorded at different bladder volumes for each volunteer. The results presented indicate that the measurements made in the two positions are in agreement using the Bland–Altman method and a parameter q which compares the values at each bladder volume for each volunteer. UBV parameters were also repeatable for measurements recorded in the supine and sitting positions.  相似文献   
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Study ObjectiveTo compare time to awakening and upper airway morbidity between desflurane and sevoflurane using a Laryngeal Mask Airway (LMA) and a balanced anesthetic regimen inclusive of opioids.DesignRandomized, double-blinded, placebo-controlled clinical trial.SettingAmbulatory surgery unit of a university hospital.Patients80 subjects receiving general anesthesia for outpatient gynecological surgery using a LMA.InterventionsDesflurane/fentanyl or sevoflurane/fentanyl were used for anesthetic maintenance.MeasurementsPatients were randomly assigned to receive desflurane or sevoflurane. The primary outcome was time to awakening as determined by an observer who was blinded to study group allocation. Secondary outcomes included the frequency of sore throat, cough, and pain perioperatively and at 2 and 24 hours postoperatively. Quality of recovery (QoR; via QoR-40 questionnaire) at 24 hours also was determined.Main ResultsThe median (IQR) time to eye opening following desflurane was 6.8 (5.0 - 9.8) minutes versus 11.8 (8.8 - 14.6) minutes following sevoflurane (P < 0.001), or a difference of 5.0 (99% CI 2.3 - 6.8) minutes. The median difference in response to verbal commands was 5.3 (99% CI 2.4 - 7.1) minutes. The frequency of cough, laryngospasm, sore throat, and hoarseness did not differ between groups. Quality of recovery at 24 hours was better in the desflurane group: difference in medians 6 (99% CI 0 – 12; P = 0.003).ConclusionsDesflurane retains faster awakening properties than does sevoflurane when used in combination with fentanyl as part of anesthetic maintenance in outpatient surgery with a LMA. The balanced anesthetic maintenance regimen seems to reduce the potential airway reactivity properties of desflurane.  相似文献   
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