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991.
A 43 kDa α-amylase was purified from Tinospora cordifolia by glycogen precipitation, ammonium sulfate precipitation, gel filtration chromatography, and HPGPLC. The enzyme was optimally active in pH 6.0 at 60 °C and had specific activity of 546.2 U/mg of protein. Activity was stable in the pH range of 4-7 and at temperatures up to 60 °C. PCMB, iodoacetic acid, iodoacetamide, DTNB, and heavy metal ions Hg2+ > Ag+ > Cd2+ inhibited enzyme activity while Ca2+ improved both activity and thermostability. The enzyme was a thiol amylase (3 SH group/mole) and DTNB inhibition of activity was released by cysteine. N-terminal sequence of the enzyme had poor similarity (12-24%) with those of plant and microbial amylases. The enzyme was equally active on soluble starch and amylopectin and released maltose as the major end product. 相似文献
992.
Koichi Matsumura Maryanne Opiekun Hiroaki Oka Anil Vachani Steven M. Albelda Kunio Yamazaki Gary K. Beauchamp 《PloS one》2010,5(1)
A potential strategy for diagnosing lung cancer, the leading cause of cancer-related death, is to identify metabolic signatures (biomarkers) of the disease. Although data supports the hypothesis that volatile compounds can be detected in the breath of lung cancer patients by the sense of smell or through bioanalytical techniques, analysis of breath samples is cumbersome and technically challenging, thus limiting its applicability. The hypothesis explored here is that variations in small molecular weight volatile organic compounds (“odorants”) in urine could be used as biomarkers for lung cancer. To demonstrate the presence and chemical structures of volatile biomarkers, we studied mouse olfactory-guided behavior and metabolomics of volatile constituents of urine. Sensor mice could be trained to discriminate between odors of mice with and without experimental tumors demonstrating that volatile odorants are sufficient to identify tumor-bearing mice. Consistent with this result, chemical analyses of urinary volatiles demonstrated that the amounts of several compounds were dramatically different between tumor and control mice. Using principal component analysis and supervised machine-learning, we accurately discriminated between tumor and control groups, a result that was cross validated with novel test groups. Although there were shared differences between experimental and control animals in the two tumor models, we also found chemical differences between these models, demonstrating tumor-based specificity. The success of these studies provides a novel proof-of-principle demonstration of lung tumor diagnosis through urinary volatile odorants. This work should provide an impetus for similar searches for volatile diagnostic biomarkers in the urine of human lung cancer patients. 相似文献
993.
994.
Adult and immature stages of a new whitefly species Dialeurodes swidi Ko are described and illustrated. It can be distinguished from other species by the abundant large tubercles scattered over its dorsum, each of them bearing a geminate pore. The biology, comparative notes and identification keys to puparia and adults of Dialeurodes species of Taiwan are provided. 相似文献
995.
Cyclooxygenase (COX) isoenzyme is known to play an important role in the pathophysiology of Parkinson's disease. The present study evaluated the neuroprotective effect of nimesulide, a preferential COX-2-inhibitor against 1-methyl-4-phenyl-1,2,3,6-tertahydropyridine (MPTP)-model of Parkinson's disease. Intrastriatal administration of MPTP (32 micromol in 2 microl) produced a significant decrease in the locomotor activity. Biochemical investigation of striatal region revealed a significant enhancement in the oxidative stress as evidenced by increased lipid peroxidation levels, nitrite levels and myeloperoxidase activity along with depleted antioxidant pool (reduced glutathione and superoxide dismutase levels) and reduced redox (GSH/GSSG) ratio. MPTP administration also showed significant mitochondrial complex-I inhibition and reduction in the mitochondrial viability. Histological examination of the MPTP-treated brain sections revealed alteration in the histo-architecture as well as undifferentiated bodies of varying contour and lesions. Chronic administration of nimesulide (5 or 10 mg/kg, po) for 12 days, significantly reversed the behavioral, biochemical, mitochondrial and histological alterations induced by MPTP. In conclusion, the findings of the present study implicate the possible neuroprotective potential of nimesulide in MPTP-treated rats and thus highlight the therapeutic potential of COX-inhibitors in treatment of Parkinson's disease. 相似文献
996.
M. K. Ratheesh Narayanan K. M. Manudev P. Sujanapal N. Anil Kumar M. Sivadasan Ahmed H. Alfarhan 《Nordic Journal of Botany》2010,28(6):713-715
Oberonia swaminathanii, a new species of Orchidaceae from Wayanad district, Kerala, India is described and illustrated. The new species resembles Oberonia balakrishnanii, O. chandrasekharanii and O. seidenfadeniana by its 3‐lobed labellum and 2‐lobuled midlobe; but differs in having brick‐red coloured flowers, triangular labellum disc, and a subglobose column. 相似文献
997.
998.
Anil Pooran Helen Booth Robert F Miller Geoff Scott Motasim Badri Jim F Huggett Graham Rook Alimuddin Zumla Keertan Dheda 《BMC pulmonary medicine》2010,10(1):1-14
Background
Obesity and asthma have reached epidemic proportions in the US. Their concurrent rise over the last 30 years suggests that they may be connected. Numerous observational studies support a temporally-correct, dose-response relationship between body mass index (BMI) and incident asthma. Weight loss, either induced by surgery or caloric restriction, has been reported to improve asthma symptoms and lung function. Due to methodological shortcomings of previous studies, however, well-controlled trials are needed to investigate the efficacy of weight loss strategies to improve asthma control in obese individuals.Methods/Design
BE WELL is a 2-arm parallel randomized clinical trial (RCT) of the efficacy of an evidence-based, comprehensive, behavioral weight loss intervention, focusing on diet, physical activity, and behavioral therapy, as adjunct therapy to usual care in the management of asthma in obese adults. Trial participants (n = 324) are patients aged 18 to 70 years who have suboptimally controlled, persistent asthma, BMI between 30.0 and 44.9 kg/m2, and who do not have serious comorbidities (e.g., diabetes, heart disease, stroke). The 12-month weight loss intervention to be studied is based on the principles of the highly successful Diabetes Prevention Program lifestyle intervention. Intervention participants will attend 13 weekly group sessions over a four-month period, followed by two monthly individual sessions, and will then receive individualized counseling primarily by phone, at least bi-monthly, for the remainder of the intervention. Follow-up assessment will occur at six and 12 months. The primary outcome variable is the overall score on the Juniper Asthma Control Questionnaire measured at 12 months. Secondary outcomes include lung function, asthma-specific and general quality of life, asthma medication use, asthma-related and total health care utilization. Potential mediators (e.g., weight loss and change in physical activity level and nutrient intake) and moderators (e.g., socio-demographic characteristics and comorbidities) of the intervention effects also will be examined.Discussion
This RCT holds considerable potential for illuminating the nature of the obesity-asthma relationship and advancing current guidelines for treating obese adults with asthma, which may lead to reduced morbidity and mortality related to the comorbidity of the two disorders.Trial registration
NCT00901095 相似文献999.
1000.
Shilpi Sinha Mushir Ali Sanjula Baboota Alka Ahuja Anil Kumar Javed Ali 《AAPS PharmSciTech》2010,11(2):518-527
Ritonavir is an antiretroviral drug characterized by low solubility and high permeability which corresponds to BCS class II
drug. The purpose of the study was to develop solid dispersion by different methods and investigate them for in vitro and in vivo performance for enhancing dissolution and bioavailability, respectively. Since the drug possesses food-related absorption,
the effect of biorelevant media (FaSSIF and FeSSIF state) on dissolution behavior was also studied. The solid dispersion was
prepared using Gelucire as carrier in 1:4 ratio by different methods and were characterized for differential scanning calorimetry
(DSC), X-ray diffractometry, scanning electron microscopy, and FT-IR. Oral bioavailability of 10 mg of ritonavir in solid
dispersion prepared by solvent evaporation (SE1) and melt method (MM1) was compared with pure drug after oral administration
of solid dispersion and pure drug to Albino Wistar rats of either sex. The results suggested formation of eutectic solid dispersion.
In vitro dissolution studies was performed in 0.1 N HCl and biorelevant media showed enhanced dissolution rate as compared to pure
drug in both FeSSIF media and 0.1 N HCl. The apparent rate of absorption of ritonavir from SE1 (C
max 20221.37 ng/ml, t
max 0.5 h) was higher than that of MM1 (C
max 2,462.2, t
max 1 h) and pure drug (C
max 1,354.8 ng/ml, t
max 0.5 h). On the basis of the result obtained, it was concluded that solid dispersion is a good approach to enhance solubility
and bioavailability of poorly water-soluble ritonavir. 相似文献