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51.
Zenker's diverticulum, though counnon in western countries is uncommon in India. This diverticuham is an extension of umcosa through Killian's dehiscence. Various surgical methods have been described for the treatment of this condition including the use of lasers but none in Indian Journals. In this paper we describe a case of Zenker's diverticulum where diverticulotomy using KTP532 laser was successfully performed. Its advantages over other techniques are mentioned.  相似文献   
52.
The series of vasicine (1) analogues, an alkaloid from Adhatoda vasica Nees., were synthesized with changes in A, B or C rings. Compounds 13-19 were evaluated for in vitro bronchodilatory activity using isolated guinea pig tracheal chain. Compounds 3-8 were also synthesized in good yields using microwave-mediated synthesis under solvent free conditions. Compounds 5 and 8 with seven-member C ring were more active than etofylline and caused 100% relaxation of both the histamine and acetycholine pre-contracted guinea pig tracheal chain. The structure-activity relationship studies showed that the quinazoline and oxo functionalities were essential for activity. The compounds without C ring and instead having aliphatic and phenyl substitutions in B ring showed relaxation against histamine pre-contracted tracheal chain only, 2-methyl substituted analogues, 12 and 13, being most active with 100% relaxation effect.  相似文献   
53.
Statins are a class of lipid-lowering medications used worldwide by millions of people and are safe for frequent use in most patients. However, they cause necrotizing autoimmune myopathy in some patients. We reviewed case reports of 80 patients from 2010 to present diagnosed with statin-induced necrotizing autoimmune myopathy (SINAM), aiming to analyze the clinical, physiological, serologic characteristics and outcomes of SINAM. The mean age of these patients was 66 ±9.4, the majority being male (61.3%). All patients reported proximal muscle weakness, and a few had myalgias, extra muscular symptoms such as dysphagia, and pulmonary complications. Most of the patients were on atorvastatin, simvastatin, or rosuvastatin. The mean creatine kinase was 10,094.2 ±7,351.7 U/l, and anti-3-hydroxy-3-methylglutaryl-coenzyme A reductase enzyme was positive for 93.8% of patients. The majority of patients were started on steroids; other treatments were also used. Prompt cessation of statins and initiation of immunosuppressants reduced morbidity and mortality.  相似文献   
54.

Ethnopharmacological relevance

The bark of Tecomella undulata is primarily used in the treatment of syphilis, painful swellings and cancer by traditional healers. Also, it is claimed to be useful in treating urinary discharges, enlargement of spleen, leucorrhoea, leukoderma, tumors, liver disorders, gonorrhea, gout and promotes wound healing in Indian traditional system of medicine.

Aim

To establish a scientific validation for the antitumor effects of Tecomella undulata bark and explore the mechanistic pathway in chronic myeloid leukemia cell line, K562. The study was further extended to standardize the extract using quercetin as biomarker.

Methods

Induction of apoptosis by chloroform extract of Tecomella undulata bark (CTUB) was determined by MTT, Annexin V and caspase activation assays. The cell cycle analysis was done by flow cytometer and nuclear staining by DAPI. The standardization of the extract was performed through reverse phase-HPLC method under PDA detection.

Result

Results clearly showed the induction of apoptosis by CTUB in K562 cells. The effect was found to be dose dependent, having IC50 of 30 μg/ml with activation of FAS, FADD, caspase 8, caspase 3/7 and fragmentation of DNA. The bioactive CTUB was determined to possess 0.03% (w/w) of quercetin.

Conclusion

The investigation clearly demonstrated the potential antitumor effect of CTUB, thereby validating the traditional claim. Quercetin, known to have anticancer activity is being reported and quantified for the first time from the bark of Tecomella undulata.  相似文献   
55.
In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis.  相似文献   
56.
57.
Primary simian varicella virus (SVV) infection and reactivation in nonhuman primates is a valuable animal model in the study of varicella zoster virus disease [varicella (chickenpox) and herpes zoster (shingles)]. To understand SVV pathogenesis in skin, we inoculated 10 rhesus macaques with SVV, resulting in varicella rash. After the establishment of latency, eight of the monkeys were immunosuppressed using tacrolimus with or without irradiation and prednisone and two monkeys were not immunosuppressed. Zoster rash developed in all immunosuppressed monkeys and in one non-immunosuppressed monkey. Five monkeys had recurrent zoster. During varicella and zoster, SVV DNA in skin scrapings ranged from 50 to 107 copies/100 ng of total DNA and 2–127 copies/100 ng of total DNA, respectively. Detection of SVV DNA in blood during varicella was more frequent and abundant compared to that of zoster. During varicella and zoster, SVV antigens colocalized with neurons expressing β-III tubulin in epidermis, hair follicles, and sweat glands, suggesting axonal transport of the virus. Together, we have demonstrated that both SVV DNA and antigens can be detected in skin lesions during varicella and zoster, providing the basis for further studies on SVV skin pathogenesis, including immune responses and mechanisms of peripheral spread.  相似文献   
58.
The fabrication of fiber-reinforced metal matrix composites (MMCs) mainly consists of two stages: infiltration and solidification, which have a significant influence on the properties of MMCs. The present study is primarily focused on the simulation of the solidification process and the effect of the active cooling of fibers with and without nickel coating for making the continuous carbon fiber-reinforced aluminum matrix composites. The thermomechanical finite element model was established to investigate the effects of different cooling conditions on the temperature profile and thermal stress distributions based on the simplified physical model. The predicted results of the temperature distribution agree well with the results of the references. Additionally, a three-dimensional cellular automata (CA) finite element (FE) model is used to simulate the microstructure evolution of the solidification process by using ProCAST software. The results show that adding a nickel coating can make the heat flux smaller in the melt, which is favorable for preventing debonding at the coating/fiber and alloy interface and obtaining a finer microstructure. In the presence of the nickel coating, the number of grains increases significantly, and the average grain size decreases, which can improve the properties of the resultant composite materials. Meanwhile, the predicting results also show that the interfaces of fiber–coating, fiber–melt, and coating–melt experience higher temperature gradients and thermal stresses. These results will lead to the phenomenon of stress concentration and interface failure. Thus, it was demonstrated that these simulation methods could be helpful for studying the solidification of fiber-reinforced MMCs and reducing the number of trial-and-error experiments.  相似文献   
59.
60.
The effects of morphine sulfate on rectal temperature and on Ca++-stimulated Mg++ATPase activity in crude synaptosomal fraction (P2) of cortex, hypothalamus and cerebellum were investigated in rat. Morphine (3-15 mg/kg, SC) produced hyperthermia at 30-120 min after the drug administration. The Ca++/Mg++ ATPase activity in hypothalamus and cortex was decreased while there was no change in Mg++ ATPase activity. The enzyme activity in cerebellum was not affected. The opiate antagonist naloxone hydrochloride (5 mg/kg, SC) antagonized the effect of morphine on rectal temperature and Ca++/Mg++ ATPase activity. The effects of different calcium channel antagonists (nimodipine 1 mg/kg, verapamil 2.5 mg/kg and diltiazem 10 mg/kg, SC) on the changes induced by morphine were also investigated. These antagonists not only antagonized morphine hyperthermia, but also the inhibitory effect of morphine on Ca++/Mg++ ATPase activity in hypothalamus. The calcium channel agonist BAY K8644 (3 mg/kg, SC) produced hypothermia and also stimulation of Ca++/Mg++ ATPase activity in hypothalamus. Naloxone failed to alter these effects of BAY K8644. These studies demonstrate that Ca++ transport in hypothalamus, as indicated by Ca++/Mg++ ATPase activity, plays an important role in thermoregulation and thermoregulatory changes induced by opiates.  相似文献   
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