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51.
There is general belief that only pure phytomolecules may be used as molecular therapeutic agent through one to one action. However, the traditional systems of medicine e.g. Ayurveda, uses the crude extracts, mostly water decoctions and oils, as drug. A comparative study of hexane, ethyl acetate and methanol fractions of N. Sativa seeds has been carried out on fresh rat-peritoneal-macrophage culture with reference to their role on various targets of lipopolysaccharide induced release of nitric oxide (NO) and inducible nitric oxide synthase (iNOS) expression. The results indicated significant antioxidant potential with methanolic extract as most effective. Its mechanism of action was proposed primarily through its antioxidant potential and not through direct inhibition of other kinases, involved in its signaling cascade.  相似文献   
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Transrectal palpation of an 18-mo-old, anestrous Holstein nulligravida revealed an enlarged left ovary. Ultrasonographically, the mass resembled known equine granulosa cell tumor (GCT) images. Slowly, virilism developed. Fifty-five days after initial diagnosis, unilateral ovariectomy was performed The presurgical serum concentration of testosterone was equal to that of a mature bull. During the 3 mo period following surgery, estrus expression resumed, the serum testosterone concentration returned to baseline, and the heifer was diagnosed pregnant following AI. A low grade, malignant GCT was the final histopathologically diagnosis. Clinical diagnosis of GCT should involve ultrasonography and steroid hormone assay. An ultrasound image, similar to the one shown, may be characteristic of GCT in the bovine.  相似文献   
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High altitude pulmonary edema (HAPE) is experienced by non-acclimatized sea level individuals on exposure to high altitude hypoxic conditions. Available evidence suggests that genetic factors and perturbed mitochondrial redox status may play an important role in HAPE pathophysiology. However, the precise mechanism has not been fully understood. In the present study, sequencing of mitochondrial DNA (mtDNA) from HAPE subjects and acclimatized controls was performed to identify pathogenic mutations and to determine their role in HAPE. Hypobaric hypoxia induced oxidative stress and metabolic alterations were also assessed in HAPE subjects. mtDNA copy number, mitochondrial oxidative phosphorylation (mtOXPHOS) activity, mitochondrial biogenesis were measured to determine mitochondrial functions. The data revealed that the mutations in Complex I genes affects the secondary structure of protein in HAPE subjects. Further, increased oxidative stress during hypobaric hypoxia, reduced mitochondrial biogenesis and mtOXPHOS activity induced metabolic reprogramming appears to contribute to mitochondrial dysfunctions in HAPE individuals. Haplogroup analysis suggests that mtDNA haplogroup H2a2a1 has potential contribution in the pathobiology of HAPE in lowlanders. This study also suggests contribution of altered mitochondrial functions in HAPE susceptibility.  相似文献   
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Fatty acid synthase (FASN) catalyzes the de novo synthesis of palmitate, a fatty acid utilized for synthesis of more complex fatty acids, plasma membrane structure, and post-translational palmitoylation of host and viral proteins. We have developed a potent inhibitor of FASN (TVB-3166) that reduces the production of respiratory syncytial virus (RSV) progeny in vitro from infected human lung epithelial cells (A549) and in vivo from mice challenged intranasally with RSV. Addition of TVB-3166 to the culture medium of RSV-infected A549 cells reduces viral spread without inducing cytopathic effects. The antiviral effect of the FASN inhibitor is a direct consequence of reducing de novo palmitate synthesis; similar doses are required for both antiviral activity and inhibition of palmitate production, and the addition of exogenous palmitate to TVB-3166-treated cells restores RSV production. TVB-3166 has minimal effect on RSV entry but significantly reduces viral RNA replication, protein levels, viral particle formation and infectivity of released viral particles. TVB-3166 substantially impacts viral replication, reducing production of infectious progeny 250-fold. In vivo, oral administration of TVB-3166 to RSV-A (Long)-infected BALB/c mice on normal chow, starting either on the day of infection or one day post-infection, reduces RSV lung titers 21-fold and 9-fold respectively. Further, TVB-3166 also inhibits the production of RSV B, human parainfluenza 3 (PIV3), and human rhinovirus 16 (HRV16) progeny from A549, HEp2 and HeLa cells respectively. Thus, inhibition of FASN and palmitate synthesis by TVB-3166 significantly reduces RSV progeny both in vitro and in vivo and has broad-spectrum activity against other respiratory viruses. FASN inhibition may alter the composition of regions of the host cell membrane where RSV assembly or replication occurs, or change the membrane composition of RSV progeny particles, decreasing their infectivity.  相似文献   
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Adrenergic stimulation of the heart initiates a signaling cascade in cardiac myocytes that increases the concentration of cAMP. Although cAMP elevation may occur over a large area of a target-organ cell, its effects are often more restricted due to local concentration of its main effector, protein kinase A (PKA), through A-kinase anchoring proteins (AKAPs). The HERG potassium channel, which produces the cardiac rapidly activating delayed rectifying K(+) current (I (Kr)), is a target for cAMP/PKA regulation. PKA regulation of the current may play a role in the pathogenesis of hereditary and acquired abnormalities of the channel leading to cardiac arrhythmia. We examined the possible role for AKAP-mediated regulation of HERG channels. Here, we report that the PKA-RII-specific AKAP inhibitory peptide AKAP-IS perturbs the distribution of PKA-RII and diminishes the PKA-dependent phosphorylation of HERG protein. The functional consequence of AKAP-IS is a reversal of cAMP-dependent regulation of HERG channel activity. In further support of AKAP-mediated targeting of kinase to HERG, PKA activity was coprecipitated from HERG expressed in HEK cells. Velocity gradient centrifugation of solubilized porcine cardiac membrane proteins showed that several PKA-RI and PKA-RII binding proteins cosediment with ERG channels. A physical association of HERG with several specific AKAPs with known cardiac expression, however, was not demonstrable in heterologous cotransfection studies. These results suggest that one or more AKAP(s) targets PKA to HERG channels and may contribute to the acute regulation of I (Kr) by cAMP.  相似文献   
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Cartilage grafting has been used extensively to correct both the functional and aesthetic aspects of the nasal framework. The technique described by Erol ( 105: 2229, 2000) uses Surgicel-wrapped diced cartilage grafts in rhinoplasties. The advantages include its ease of preparation, the large volume of graft substrate available for use, and the avoidance of contour irregularities in the areas of placement. A retrospective case review of 67 consecutive patients who were treated with a Surgicel-wrapped diced cartilage graft as part of an aesthetic and/or functional rhinoplasty, in a 5-year period between 1995 and 2000, was performed in this study. All cases of congenital nasal deformities or deformities caused by trauma or tumors in which the technique was used were excluded. The charts were reviewed to determine demographic variables, the surgical procedures performed, prior operations, the rhinoplasty approach used, and the graft donor and recipient sites. Preoperative and postoperative photographs were examined, and the results were assessed. Data on the donor and recipient sites, complications, and the necessity for revisionary procedures were tabulated. There were two complications, namely, an infection, which resolved with aspiration and oral antibiotic therapy, and a recurrence of a dorsal depression, which necessitated repeated augmentation within 6 months. The technique of using Surgicel-wrapped diced cartilage proved to be effective for the augmentation of various areas of the nose. The complication and revision rates were acceptable and comparable to those of other techniques. Patient satisfaction with the aesthetic results was rated highly, with no reports of graft extrusion or contour irregularities. This technique is recommended for nasal augmentation and contouring for selected rhinoplasty patients.  相似文献   
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RNA has attracted recent attention for its key role in gene expression and hence targeting by small molecules for therapeutic intervention. This study is aimed to elucidate the specificity of RNA binding affinity of parent compound of N-arylhydroxamic acids series, N-phenylbenzohydroxamic acid trivially named as PBHA,C6H5NOH.C6H5C ? O. The binding behavior was examined by various biophysical methods such as absorption, fluorescence, and viscosity measurements. Molecular docking was also done. The value of affinity constant and overall binding constant was calculated 5.79 ± 0.03 × 104 M?1 and K’ = 1.09 ± 0.03 × 105 M?1, respectively. The Stern-Volmer constant Ksv obtained was 2.28 ± 0.04 × 104 M?1. The compound (PBHA) shows a concentration-based enhancement of fluorescence intensity with increasing RNA concentration. Fluorescence quenching of PBHA–RNA complex in presence of K4 [Fe(CN)6] was also observed. Viscometric studies complimented the UV results where a continuous increase in relative viscosity of the RNA solution was observed with added optimal PBHA concentration. All the experimental evidences indicate that PBHA can strongly bind to RNA through an intercalative mode.  相似文献   
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