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61.
Alain Vuylsteke Palanikumar Saravanan Caroline Gerrard Fay Cafferty 《BMC anesthesiology》2006,6(1):1-11
Background
Cervicogenic headache (CEH) is a unilateral headache localised in the neck or occipital region, projecting to the frontal and temporal regions. Since the pathogenesis of this syndrome appears to have an anatomical basis in the cervical region, several surgical procedures aimed at reducing the nociceptive input on the cervical level, have been tested. We developed a sequence of various cervical radiofrequency neurotomies (facet joint denervations eventually followed by upper dorsal root ganglion neurotomies) that proved successful in a prospective pilot trial with 15 CEH patients. To further evaluate this sequential treatment program we conducted a randomised controlled trialMethods
30 patients with cervicogenic headache according to the Sjaastad diagnostic criteria, were randomised. 15 patients received a sequence of radiofrequency treatments (cervical facet joint denervation, followed by cervical dorsal root ganglion lesions when necessary), and the other 15 patients underwent local injections with steroid and anaesthetic at the greater occipital nerve, followed by transcutaneous electrical nerve stimulation (TENS) when necessary. Visual analogue scores for pain, global perceived effects scores, quality of life scores were assessed at 8, 16, 24 and 48 weeks. Patients also kept a headache diary.Results
There were no statistically significant differences between the two treatment groups at any time point in the trial.Conclusion
We did not find evidence that radiofrequency treatment of cervical facet joints and upper dorsal root ganglions is a better treatment than the infiltration of the greater occipital nerve, followed by TENS for patients fulfilling the clinical criteria of cervicogenic headache. 相似文献62.
63.
Kanagavel Deepankumar Nadarajan Saravanan Prabhu June-Hyung Kim Hyungdon Yun 《Biotechnology and Bioprocess Engineering》2017,22(3):248-255
In this study, we demonstrate the application of multiple functional properties of proteins generated through coupling of residue-specific and site-specific incorporation method. With green fluorescent protein (GFP) as a model protein, we constructed multifunctional GFP through sitespecific incorporation of L-3,4-dihydroxyphenylalanine (DOPA) and residue-specific incorporation of (2S, 4S)-4- fluoroproline (4S-FP) or L-homopropargylglycine (hpg). Fluorescence analysis revealed a conjugation efficiency of approximately 20% for conjugation of DOPA-containing variants GFPdopa, GFPdp[4S-FP], and GFPdphpg onto chitosan. While incorporation of 4S-FP improved protein folding and stability, hpg incorporation into GFP allowed conjugation with fluorescent dye/polyethylene glycol (PEG). In addition, the modification of GFPhpg and GFPdphpg with PEG through Cu(I)-catalyzed click reaction increased protein thermal stability by about two-fold of the wild-type GFP. 相似文献
64.
S Ramachandran Y Sridhar S Kishore Gnana Sam M Saravanan J Thomas Leonard N Anbalagan S K Sridhar 《Phytomedicine》2004,11(2-3):165-168
In the present study, the aphrodisiac activity of Butea frondonsa Koen. ex Roxb (Papillionaceae) bark extract was investigated. The extract (400 mg/kg body wt./day) was administered orally by gavage for 28 days. Mount latency (ML), intromission latency (IL), ejaculation latency (EL), mounting frequency (MF), intromission frequency (IF), ejaculation frequency (EF) and post-ejaculatory interval (PEI) were the parameters observed before and during the sexual behavior study at day 0, 7, 10, 14, 21, and 28. The extract reduced significantly ML, IL, EL and PEI (p < 0.05). The extract also increased significantly MF, IF and EF (p < 0.05). These effects were observed in sexually active and inactive male rats. 相似文献
65.
Baskaran Yogalakshmi Saravanan Bhuvaneswari S. Sreeja Carani Venkatraman Anuradha 《Journal of cell communication and signaling》2014,8(1):13-22
Key pathways like insulin signaling, AMP activated kinase (AMPK) activation and inflammatory signaling are involved in the complex pathological network of hepatic insulin resistance. Our aim is to investigate whether grape seed proanthocyanidins (GSP) and metformin (MET) target any of these pathways in insulin resistant rat liver. Albino Wistar rats were rendered insulin resistant by feeding a high fat-fructose diet (HFFD). Either GSP (100 mg/kg b.w), MET(50 mg/kg b.w) or both were administered to insulin resistant rats as therapeutic options. HFFD-feeding caused hyperglycemia, hyperinsulinemia, increased gluconeogenesis, decreased tyrosine phosphorylation of insulin receptor-β(IR-β) and insulin receptor substrate-1 (IRS-1) and increased serine phosphorylation of IRS-1. The association of p85α subunit of phosphotidyl inositol 3 kinase(PI3K) with IRS-1 and subsequent Akt phosphorylation were reduced while the expression of mitogen activated protein kinases (MAPK) were increased in HFFD rats. Both MET and GSP reduced hyperglycemia and hyperinsulinemia and improved glycolysis, tyrosine phosphorylation of IR-β and IRS-1, IRS-1-PI3K association and Akt activation. However, activation of tumor necrosis factor-α, interleukin-6, leptin and suppressor of cytokine signaling-3 and reduction in adiponectin caused by chronic HFFD feeding were reversed by GSP better than by MET. Activation of AMPK by GSP was much less compared to that by MET. These findings suggest that GSP might activate PI3K pathway and promote insulin action by reducing serine kinase activation and cytokine signaling and MET by targeting AMPK. The beneficial effects were enhanced during combination therapy. Thus, combination therapy with MET and GSP may be considered for the management of metabolic syndrome. 相似文献
66.
Andrew Wilson Joseph Paul O’Hare Ainsley Hardy Neil Raymond Ala Szczepura Ric Crossman Darrin Baines Kamlesh Khunti Sudhesh Kumar Ponnusamy Saravanan the C C D trial group 《PloS one》2014,9(4)
Background
Configuring high quality care for the rapidly increasing number of people with type 2 diabetes (T2D) is a major challenge worldwide for both providers and commissioners. In the UK, about two thirds of people with T2D are managed entirely in primary care, with wide variation in management strategies and achievement of targets. Pay for performance, introduced in 2004, initially resulted in improvements but disparities exist in ethnic minorities and the improvements are levelling off. Community based, intermediate care clinics for diabetes (ICCDs) were considered one solution and are functioning across the UK. However, there is no randomised trial evidence for the effectiveness of such clinics.Trial Design, Methods and Findings
This is a cluster-randomised trial, involving 3 primary care trusts, with 49 general practices randomised to usual care (n = 25) or intervention (ICCDs; n = 24). All eligible adult patients with T2D were invited; 1997 were recruited and 1280 followed-up after 18-months intervention. Primary outcome: achievement of all three of the NICE targets [(HbA1c≤7.0%/53 mmol/mol; Blood Pressure <140/80 mmHg; cholesterol <154 mg/dl (4 mmol/l)]. Primary outcome was achieved in 14.3% in the intervention arm vs. 9.3% in the control arm (p = 0.059 after adjustment for covariates). The odds ratio (95% CI) for achieving primary outcome in the intervention group was 1.56 (0.98, 2.49). Primary care and community clinic costs were significantly higher in the intervention group, but there were no significant differences in hospital costs or overall healthcare costs. An incremental cost-effectiveness ratio (ICER) of +£7,778 per QALY gained, indicated ICCD was marginally more expensive at producing health gain.Conclusions
Intermediate care clinics can contribute to improving target achievement in patients with diabetes. Further work is needed to investigate the optimal scale and organisational structure of ICCD services and whether, over time, their role may change as skill levels in primary care increase.Trial Registration
ClinicalTrials.gov ; National Research Register (NRR) NCT00945204M0014178167. 相似文献67.
Konda Mani Saravanan A. Keith Dunker 《Journal of biomolecular structure & dynamics》2013,31(16):4338-4351
More than 60 prediction methods for intrinsically disordered proteins (IDPs) have been developed over the years, many of which are accessible on the World Wide Web. Nearly, all of these predictors give balanced accuracies in the ~65%–~80% range. Since predictors are not perfect, further studies are required to uncover the role of amino acid residues in native IDP as compared to predicted IDP regions. In the present work, we make use of sequences of 100% predicted IDP regions, false positive disorder predictions, and experimentally determined IDP regions to distinguish the characteristics of native versus predicted IDP regions. A higher occurrence of asparagine is observed in sequences of native IDP regions but not in sequences of false positive predictions of IDP regions. The occurrences of certain combinations of amino acids at the pentapeptide level provide a distinguishing feature in the IDPs with respect to globular proteins. The distinguishing features presented in this paper provide insights into the sequence fingerprints of amino acid residues in experimentally determined as compared to predicted IDP regions. These observations and additional work along these lines should enable the development of improvements in the accuracy of disorder prediction algorithm. 相似文献
68.
69.
The human bifunctional dehydrogenase-cyclohydrolase domain catalyzes the interconversion of 5,10-methylene-H(4)folate and 10-formyl-H(4)folate. Although previous structure and mutagenesis studies indicated the importance of lysine 56 in cyclohydrolase catalysis, the role of several surrounding residues had not been explored. In addition to further defining the role of lysine 56, the work presented in this study explores the functions of glutamine 100 and aspartate 125 through the use of site-directed mutagenesis and chemical modification. Mutants at position 100 are inactive with respect to cyclohydrolase activity while preserving significant dehydrogenase levels. We succeeded in producing a K56Q/Q100K double mutant, which has no cyclohydrolase yet retains more than two-thirds of wild type dehydrogenase activity. Neither activity is detectable in aspartate 125 mutants with the exception of D125E. The results indicate that the function of glutamine 100 is to activate lysine 56 for cyclohydrolase catalysis and that aspartate 125 is involved in the binding of the H(4)folate substrates. In highlighting the importance of these residues, catalytic mechanisms are proposed for both activities as well as an explanation for the differences in channeling efficiency in the forward and reverse directions. 相似文献
70.
Rajamanickam Anuradha Saravanan Munisankar Yukthi Bhootra Jeeva Jagannathan Chandrakumar Dolla Paul Kumaran Thomas B. Nutman Subash Babu 《PLoS neglected tropical diseases》2016,10(1)