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81.
The immunoprophylactic and therapeutic potentials of root extracts of Withania somnifera chemotypes (NMITLI‐118, NMITLI‐101) and pure withanolide–withaferin A was investigated against Leishmania donovani infection in hamsters. The naive animals, fed orally with immunostimulatory doses of chemotypes 101R, 118R (10 and 3 mg/kg) and withaferin A (9 and 3 mg/kg) for five consecutive days and challenged with Leishmania parasites on day 6, were euthanized on days 30 and 45 p.c. for the assessment of parasite clearance, real‐time analysis of mRNAs of Th1/Th2 cytokines (IFN‐γ, IL‐12, TNF‐α, iNOS/IL‐4, IL‐10 and TGF‐β), NO production, reactive oxygen species (ROS) generation, lymphocyte transformation test and antibody responses. By day 45 p.c., there was a significant increase in the mRNA expression of iNOS, IFN‐γ, IL‐12 and TNF‐α but decrease in IL‐4, IL‐10 and TGF‐β, an enhanced Leishmania‐specific LTT response as well as ROS, NO and antileishmanial IgG2 levels in 101R‐treated hamsters followed by 118R‐ and withaferin A‐treated ones, respectively. When these chemotypes were given to L. donovani‐infected hamsters at different doses, there was moderate therapeutic efficacy of chemotype 101R (~50%) at 30 mg/kg × 5 followed by the other two. The results established that the 101R is the most potential chemotype and can be evaluated for combination therapy along with available antileishmanials.  相似文献   
82.

Purpose

Long-term use of rosuvastatin may be associated with myotoxicity. Statins are one of the groups commonly found to be associated with neuromuscular weakness. The present study was designed to investigate the interaction between rosuvastatin and rocuronium in vivo by using a sciatic-gastrocnemius nerve-muscle preparation of rat.

Methods

In our study groups, animals received rosuvastatin 2 mg/kg for 14 and 28 days. Train of four (TOF) stimulation was applied to the sciatic nerve, and gastrocnemius muscle contractions were recorded in Wistar albino rats. Intravenous infusion of rocuronium was given until the twitch responses were abolished. We ultimately compared the effective dose required for a desired effect in 95% of the population (ED95), duration 25 %, deep block, recovery index, and time for returning of TOF ratio to 0.9 between the active control and study groups.

Results

Chronic administration of rosuvastatin at a dose of 2 mg/kg for 28 days significantly reduced the ED95 of rocuronium as compared to the active control group. Deep block and duration 25 % were increased by 3.5 and 2.5 times, respectively, compared to the active control group. The spontaneous recovery of neuromuscular block was delayed, as evidenced by the prolonged recovery index and increase in time required for a return of the TOF ratio to 0.9.

Conclusion

The neuromuscular blocking potency of rocuronium is increased and recovery is delayed in rats that pre-treated with rosuvastatin.  相似文献   
83.
The present study investigates the process of internalization for bulk ZnO particles in macrophages, and further elucidates the underlying mechanism. Since macrophages are active phagocytes and phagocytosis is a size dependent phenomenon, therefore we hypothesized that bulk ZnO may internalize into macrophages by phagocytic pathways. Interestingly, the phagocytic activity got enhanced in bulk ZnO treated macrophages. Moreover, the bulk ZnO treated macrophages internalized via FcγR-II/III, complement and scavenger–receptor pathways. To confirm the specificity of phagocytic pathway, the uptake was also analyzed in splenocytes where phagocytic (monocytes) and non-phagocytic cells (lymphocytes) are present. It was observed that no significant uptake of bulk ZnO in case of lymphocytes whereas significant uptake in monocytes. Henceforth, our quest for uptake mechanisms also revealed that severe plasma membrane extensions (pseudopodia), FcγR clustering over the surface of macrophages and activation of FcγR signaling were the key players for bulk ZnO uptake; whereas clathrin or caveolae mediated endocytic pathways contributed less. Uptake of these particles was further strengthened by the ZnO-induced activation of the Src-kinase p-Lyn, phospho-tyrosine kinases Syk (spleen tyrosine kinase), p-PLC-γ and PI3K (phosphatidylinositol 3-kinase). Our findings illustrate that the phagocytic nature of macrophages could have led to higher uptake of bulk ZnO.  相似文献   
84.
85.
In patients with congenital heart disease (CHD), the association between supraventricular tachycardia (SVT), type of pathophysiology, and therapeutic interventions in a population-based cohort warrants further examination. A retrospective, longitudinal 15-year data set (1996–2010) was analyzed. Inclusion criteria included age ≤17 years, enrolled in South Carolina State Medicaid, and diagnosed as having one or more CHDs as well as SVT. SVT was diagnosed in 6.5 % of CHD patients (N = 1,169) during the 15-year epoch investigated. SVT was less likely to occur in African-American (hazard ratio [HR] = 0.76) or male patients (HR = 0.88), but it was significantly more likely to occur in patients age ≤12 months or in adolescents ≥13 years in those undergoing multiple surgeries/medical interventions for their CHD (HR = 1.14), those receiving antiarrhythmic/diuretic/preload-/afterload-reducing medications (HR = 5.46), and those with severe/cyanotic CHDs (HR = 1.52) or chromosomal abnormalities (HR = 1.64). Children who had an atrial septal defect secundum (adjusted odds ratio [aOR] = 3.03) and those treated with diuretic or antiarrhythmic medication (aOR = 1.80) were significantly more likely to undergo SVT ablation, whereas those with late-onset pulmonary hypertension (ages 6–12 years old) were significantly less likely to undergo SVT ablation. SVT recurred in only 14 of 166 patients who underwent SVT ablation. Multiple medical interventions at an early age may increase the risk of SVT occurrence in young CHD patients regardless of the severity/complexity of the CHD.  相似文献   
86.
Molecular Imaging and Biology - Scintigraphic imaging of malignant glioblastoma (MG) continues to be challenging. We hypothesized that VPAC1 cell surface receptors can be targeted for positron...  相似文献   
87.
We have investigated the effect of shilajit on lipid peroxidation and glutathione content in rat liver homogenate. It inhibited lipid peroxidation induced by cumene hydroperoxide and ADP/Fe++ complex in a dose dependent manner. It also reduced the rate of oxidation of reduced glutathione content and inhibited ongoing lipid peroxidation, induced by these agents immediately after its addition to the incubation system.  相似文献   
88.
Ursolic acid isolated from the leaves and stems of Duboisia myoporoides (Solanaceae) was bioassayed by leaf disc method for feeding deterrence using Spilosoma obliqua and Spodoptera litura as test insects. This compound was proved to be a potent antifeedant under laboratory conditions. Azadirachtin was used as standard. Ursolic acid produced 90.12% and 91.96% inhibition at 5000 ppm concentration, respectively, against S. obliqua and S. litura .  相似文献   
89.
90.
A simple and efficient route to develop various novel functionalized MOF materials for rapid and excellent recovery of U(vi) from aqueous medium, along with selective sensing has been demonstrated in the present study. In this connection, a set of four distinct post synthetically modified (PSM) iso-reticular metal organic frameworks were synthesized from IRMOF-3 namely, IRMOF-PC (2-pyridine carboxaldehyde), IRMOF-GA (glutaric anhydride), IRMOF-SMA (sulfamic acid), and IRMOF-DPC (diphenylphosphonic chloride) for the recovery and sensing of U(vi) from aqueous medium. The MOFs were characterized by Fourier transform infrared spectroscopy (FTIR), powder XRD, BET surface area analysis, thermogravimetric analysis (TGA), NMR (13C, 1H and 31P), Scanning Electron Microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX). Among all MOFs, post synthetically modified IRMOF-SMA showed enhanced thermal stability of about 420 °C. The MOFs were investigated for U(vi) sorption studies using a batch technique. All the MOFs exhibit excellent sorption capacity towards U(vi) (>90%) and maximum uptake was observed at pH 6. Sorption capacity of MOFs have the following order; IRMOF-3-DPC (300 mg U g−1) > IRMOF-SMA (292 mg U g−1) > IRMOF-PC (289 mg U g−1) > IRMOF-GA (280 mg U g−1) > IRMOF-3 (273 mg U g−1). IRMOF-DPC shows rapid sorption of uranium within 5 min with excellent uptake of U(vi) (>99%). The desorption of U(vi) was examined with different eluents and 0.01 M HNO3 was found to be most effective. The fluorescence sensing studies of U(vi) via IRMOF-3 and its PSM MOFs revealed high sensitivity and selectivity towards U(vi) over other competing rare earth metal ions (La3+, Ce4+, Sm3+, Nd3+, Gd3+, and Eu3+), wherein IRMOF-GA displayed an impressive detection limit of 0.36 mg L−1 for U(vi).

Four IRMOFs following PSM strategy were prepared. The MOFs were characterized by different techniques and were investigated for U(vi) sorption. PSM MOFs displayed impressive fluorescent sensing and selectivity of U(vi) over competing metal ions.  相似文献   
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