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Oh J, Choi J, Suh J, Liu H, Hwang K, Chung I, Lee S, Kang J, Park H, Jung W, Jo S, Gweon H, Lee Y, Lee W, Kim J, Han S, Hong G, Lee J, Lee B, Yeo C, Kim H, Seo E, Reynaud P, Goff J, Tan H, Tao J. Preliminary design of the ITER AC/DC converters supplied by the Korean Domestic Agency. FUSION ENGINEERING AND DESIGN 2013. [DOI: 10.1016/j.fusengdes.2013.01.099] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Tang VM, Young AH, Tan H, Beasley C, Wang JF. Glucocorticoids increase protein carbonylation and mitochondrial dysfunction. Horm Metab Res 2013; 45:709-15. [PMID: 23670350 DOI: 10.1055/s-0033-1345119] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Many major psychiatric illnesses have been associated with excessive and prolonged release of glucocorticoid stress hormones potentially leading to deleterious neuronal effects. Recent studies have suggested that oxidative stress is associated with psychiatric illnesses. Oxidative stress is an overproduction of reactive oxygen species (ROS) that overwhelms the cellular antioxidant capacity. The mitochondria are responsible for most oxygen consumption and are a major source of ROS production. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase also contributes significantly to ROS production. This study aims to elucidate the effects of glucocorticoids on oxidative damage to protein, mitochondrial function, NADPH oxidase activity, and antioxidant capacity. Rat pheochromocytoma PC12 cells were treated with corticosterone at concentrations of 0.031, 0.063, and 0.125 mmol/l for 24 h. Protein carbonylation, activities of mitochondrial complex I and III, activity of NADPH oxidase, total antioxidant capacity, and activities of superoxide dismutase (SOD) and catalase (CAT) were analyzed. We found that chronic treatment with corticosterone increased the amount of protein carbonylation in PC12 cells. Complex I activity was decreased with corticosterone treatment, while no change was seen in complex III activity or NADPH oxidase activity. Total antioxidant capacity was increased at the lowest dosage level tested. Although corticosterone treatment had no effect on CAT activity, corticosterone at the highest dosage significantly decreased SOD activity. These results suggest that excessive glucocorticoid activity can increase oxidative damage to protein, possibly by inhibiting activities of mitochondrial complex I and antioxidant enzyme SOD.
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Tan H, Ding X, Meng S, Liu C, Wang H, Xia L, Liu Z, Liang S. Antimicrobial Potential of Lycosin-I, a Cationic and Amphiphilic Peptide from the Venom of the Spider Lycosa singorensis. Curr Mol Med 2013; 13:900-10. [DOI: 10.2174/15665240113139990045] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 04/23/2013] [Accepted: 04/29/2013] [Indexed: 11/22/2022]
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Tan H, Gupta P, Harness J, Wolk R, Chapel S, Menter A, Strober B, Langley RG, Krishnaswami S, Papp KA. Dose Response and Pharmacokinetics of Tofacitinib (CP-690,550), an Oral Janus Kinase Inhibitor, in the Treatment of Chronic Plaque Psoriasis. CPT-PHARMACOMETRICS & SYSTEMS PHARMACOLOGY 2013. [PMCID: PMC3674331 DOI: 10.1038/psp.2013.22] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Longitudinal nonlinear mixed effects modeling was used to characterize the dose–response profile of tofacitinib using data from a placebo-controlled dose-ranging study, where tofacitinib 2, 5, and 15 mg twice daily (b.i.d.) were evaluated for plaque psoriasis treatment. Bayesian estimation was applied with prior information derived from the literature: nonclinical and clinical data in psoriasis, as well as other indications. The probability to achieve a certain target effect associated with a given dose was calculated from the posterior samples. On the basis of these probabilities along with safety considerations, tofacitinib 5 and 10 mg b.i.d. were selected for further testing in confirmatory phase III clinical trials. Pharmacokinetics in patients with psoriasis was characterized using a population-based modeling approach, and body weight was identified as an important covariate. A subgroup analysis suggested reduced efficacy of tofacitinib with increasing body weight; however, it is unclear whether this trend could be explained by systemic exposure alone.
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Lu Y, Wang J, Deng Z, Wu H, Deng Q, Tan H, Cao L. Isolation and characterization of fatty acid methyl ester (FAME)-producing Streptomyces sp. S161 from sheep (Ovis aries) faeces. Lett Appl Microbiol 2013; 57:200-5. [PMID: 23692633 DOI: 10.1111/lam.12096] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Revised: 04/23/2013] [Accepted: 04/26/2013] [Indexed: 12/26/2022]
Abstract
An actinomycete producing oil-like mixtures was isolated and characterized. The strain was isolated from sheep faeces and identified as Streptomyces sp. S161 based on 16S rRNA gene sequence analysis. The strain showed cellulase and xylanase activities. The (1) H nuclear magnetic resonance (NMR) spectra of the mixtures showed that the mixtures were composed of fatty acid methyl esters (52·5), triglycerides (13·7) and monoglycerides (9·1) (mol.%). Based on the gas chromatography-mass spectrometry (GC-MS) analysis, the fatty acid methyl esters were mainly composed of C14-C16 long-chain fatty acids. The results indicated that Streptomyces sp. S161 could produce fatty acid methyl esters (FAME) directly from starch. To our knowledge, this is the first isolated strain that can produce biodiesel (FAME) directly from starch.
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Kikuchi T, Tan H, Mihara T, Uchimoto K, Mitsushima D, Takase K, Morita S, Goto T, Andoh T, Kamiya Y. Effects of volatile anesthetics on the circadian rhythms of rat hippocampal acetylcholine release and locomotor activity. Neuroscience 2013; 237:151-60. [DOI: 10.1016/j.neuroscience.2013.01.062] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2012] [Revised: 01/21/2013] [Accepted: 01/22/2013] [Indexed: 10/27/2022]
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Turan MI, Cayir A, Cetin N, Suleyman H, Turan IS, Tan H. An investigation of the effect of thiamine pyrophosphate on cisplatin-induced oxidative stress and DNA damage in rat brain tissue compared with thiamine. Hum Exp Toxicol 2013; 33:14-21. [DOI: 10.1177/0960327113485251] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
This study investigated the effects of thiamine pyrophosphate (TPP) at dosages of 10 and 20 mg/kg on oxidative stress induced in rat brain tissue with cisplatin and compared this with thiamine. Cisplatin neurotoxicity represents one of the main restrictions on the drug being given in effective doses. Oxidative stress is considered responsible for cisplatin toxicity. Our results showed that cisplatin increased the levels of oxidant parameters such as lipid peroxidation (thio barbituric acid reactive substance (TBARS)) and myeloperoxidase (MPO) in brain tissue and suppressed the effects of antioxidants such as total glutathione (GSH) and superoxide dismutase (SOD). TPP, especially at a dosage of 20 mg/kg, significantly reduced TBARS and MPO levels that increase with cisplatin administration compared with the thiamine group, while TPP significantly increases GSH and SOD levels. In addition, the level of 8-Gua (guanine), a product of DNA damage, was 1.7 ± 0.12 8-hydroxyl guanine (8-OH Gua)/105 Gua in brain tissue in the control group receiving cisplatin, compared with 0.97 ± 0.03 8-OH Gua/105 Gua in the thiamine pyrophosphate (20 mg/kg) group and 1.55 ± 0.11 8-OH Gua/105 Gua in the thiamine (20 mg/kg) group. These results show that thiamine pyrophosphate significantly prevents oxidative damage induced by cisplatin in brain tissue, while the protective effect of thiamine is insignificant.
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Wang J, Yang Y, Zhu J, Tan H, Liu L. Predicting factors of short term mortality in patients with acute ST-elevation myocardial infarction complicated by fatal arrhythmia. Int J Cardiol 2013. [DOI: 10.1016/s0167-5273(13)70554-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Puttarajappa C, Yabes J, Bei L, Shah N, Bernardo J, McCauley J, Basu A, Tan H, Shapiro R, Unruh M, Wu C. Cancer risk with alemtuzumab following kidney transplantation. Clin Transplant 2013; 27:E264-71. [PMID: 23480032 DOI: 10.1111/ctr.12094] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/18/2012] [Indexed: 12/16/2022]
Abstract
Alemtuzumab has been employed for induction therapy in kidney transplantation with low rates of acute rejection and excellent graft and patient survival. Antibody induction therapy has been linked to increased vulnerability to cancer. Data regarding malignancy rates with alemtuzumab are limited. We studied 1350 kidney transplant recipients (between 2001 and 2009) at the University of Pittsburgh Starzl Transplant Institute, for post-transplant de novo and recurrent malignancy, excluding non-melanoma skin cancer, among patients receiving alemtuzumab, thymoglobulin, and no induction therapies. Of the 1350 patients, 1002 (74.2%) received alemtuzumab, 205 (15.2%) received thymoglobulin, and 122 (9%) received no induction therapy. After excluding cancers occurring within 60 d post-transplantation, 43 (3.25%) malignancies were observed during a median follow-up time of 4.0 yr. The incidence of malignancy was 5.4% (1.09 per 100 patient-years [PY]) with thymoglobulin, 2.8% (0.74 per 100 PY) with alemtuzumab, and 3.3% (0.66 per 100 PY) with no induction (across all groups; p = 0.2342, thymoglobulin vs. alemtuzumab; p = 0.008). Thus, with the exception of non-melanoma skin cancer which we did not evaluate, alemtuzumab induction was not associated with increased cancer incidence post-kidney transplantation when compared to no induction therapy and was associated with lower cancer incidence when compared to thymoglobulin.
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Tan H, Li R, Peng W, Liu H, Gu Y, Shen X. Radiological and clinical features of adult non-puerperal mastitis. Br J Radiol 2013; 86:20120657. [PMID: 23392197 DOI: 10.1259/bjr.20120657] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
OBJECTIVE To describe the radiological and clinical features of adult non-puerperal mastitis and to determine the most accurate method of preventing unnecessary surgical procedures. METHODS Clinical and imaging findings were retrospectively reviewed in 51 females with non-puerperal mastitis, which was confirmed by biopsy/surgical pathology. All 51 patients had pre-operative MRI; 45 patients also had sonograms and 25 also had mammograms, pre-operatively. RESULTS Of the 51 cases with non-puerperal mastitis, 94.1% (48/51) were confirmed as having acute or chronic inflammation, and the other 3 had plasma cell mastitis; areola papillaris inflammation was found in 39.2% (20/51) of the cases. Overall, 6 of the 25 cases that were examined with mammography and 2 of the 45 cases that were examined with sonography appeared normal, but all 51 lesions were positively identified on MRI. Asymmetrical density (12/25) on mammograms and solitary or separated/contiguous, clustered, hypoechoic mass-like lesions (31/45) on ultrasound were the most common signs of non-puerperal mastitis. On enhanced MRI, 90.2% (46/51) of patients showed non-mass-like enhanced lesions. Multiple regional enhancements in the pattern of distribution (32/46) and separated or contiguous, clustered, rim-like enhancements in the pattern of internal enhancement (29/46) were the most common manifestations in non-mass-like enhanced lesions. Of the 51 patients, mastitis Type 1 and Type 2 in the time-signal intensity curve were detected in 47.1% and 51.0% of the patients, respectively. The breast imaging reporting and data system categories with the highest number of patients were Category 0 (9/25) on mammography, Category 4a on sonography (18/45) and Category 4a on MRI (29/51). CONCLUSION The findings from mammography and ultrasound are non-specific; therefore, using MR can be helpful in the diagnosis, especially in the presence of non-mass-like enhancements that are multiple, regional, separated, or contiguous, clustered and rim-like. ADVANCES IN KNOWLEDGE Mastitis is often neglected because of the lack of typical clinical signs and symptoms. This study has assessed and described the clinical features and imaging findings of adult non-puerperal mastitis on mammograms, sonograms and MRI and found that MRI is more specific in the diagnosis of disease.
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Papp KA, Menter A, Strober B, Langley RG, Buonanno M, Wolk R, Gupta P, Krishnaswami S, Tan H, Harness JA. Efficacy and safety of tofacitinib, an oral Janus kinase inhibitor, in the treatment of psoriasis: a Phase 2b randomized placebo-controlled dose-ranging study. Br J Dermatol 2013; 167:668-77. [PMID: 22924949 DOI: 10.1111/j.1365-2133.2012.11168.x] [Citation(s) in RCA: 233] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Tofacitinib is a novel, oral Janus kinase inhibitor under investigation as a potential treatment for plaque psoriasis. OBJECTIVES This Phase 2b, 12-week, dose-ranging study (A3921047, NCT00678210) aimed to characterize the exposure-response, efficacy and safety of tofacitinib vs. placebo in patients with moderate-to-severe chronic plaque psoriasis. METHODS One hundred and ninety-seven patients were randomized. The primary endpoint was the proportion of patients achieving a ≥ 75% reduction in the Psoriasis Area and Severity Index (PASI 75) score at week 12. RESULTS At week 12, PASI 75 response rates were significantly higher for all tofacitinib twice-daily groups: 25·0% (2 mg; P < 0·001), 40·8% (5 mg; P < 0·0001) and 66·7% (15 mg; P < 0·0001), compared with placebo (2·0%). Significant increases in the proportion of PASI 75 responses were seen by week 4 and were maintained at week 12. Exposure-response over the 0-15 mg tofacitinib twice-daily dose range was successfully characterized. PASI 50, PASI 90 and Physician's Global Assessment response rates were also higher for tofacitinib vs. placebo. The most frequently reported adverse events (AEs) were infections and infestations: 22·4% (2 mg twice daily), 20·4% (5 mg twice daily), 36·7% (15 mg twice daily) and 32·0% (placebo). Discontinuations due to AEs were 6·0%, 2·0%, 4·1% and 6·1% of patients in the placebo, and 2, 5 and 15 mg twice-daily tofacitinib groups, respectively. Dose-dependent increases from baseline in mean serum high-density lipoprotein, low-density lipoprotein and total cholesterol, and decreases in haemoglobin and neutrophils were observed. CONCLUSION Short-term treatment with oral tofacitinib results in significant clinical improvement in patients with moderate-to-severe plaque psoriasis and is generally well tolerated.
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Mamolo C, Harness J, Tan H, Menter A. Tofacitinib (CP-690,550), an oral Janus kinase inhibitor, improves patient-reported outcomes in a phase 2b, randomized, double-blind, placebo-controlled study in patients with moderate-to-severe psoriasis. J Eur Acad Dermatol Venereol 2013; 28:192-203. [DOI: 10.1111/jdv.12081] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2012] [Accepted: 11/26/2012] [Indexed: 11/26/2022]
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Henk HJ, Becker L, Tan H, Yu J, Kavati A, Naeim A, Deeter R, Barron R. Comparative effectiveness of pegfilgrastim, filgrastim, and sargramostim prophylaxis for neutropenia-related hospitalization: two US retrospective claims analyses. J Med Econ 2013; 16:160-8. [PMID: 23016568 DOI: 10.3111/13696998.2012.734885] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE Few studies have compared the effectiveness of filgrastim (FIL), pegfilgrastim (PEG), and sargramostim (SAR) to reduce the risk of febrile neutropenia (FN) associated with myelosuppressive chemotherapy (M-CT). Two large commercial database analyses were separately conducted to examine the incidence of neutropenia-related and all-cause hospitalizations associated with FIL, PEG, and SAR prophylaxis for patients receiving M-CT for non-Hodgkin lymphoma (NHL), Hodgkin lymphoma, or solid tumors. METHODS Separate retrospective US claims database analyses utilized patient data from January 1, 2004 to April 30, 2010 using the HealthCore Integrated Research Database (HIRD(SM)) and January 1, 2001 to August 31, 2009 using OptumInsight's (formerly Ingenix) database. Patients were ≥18 years old and treated with M-CT for NHL, Hodgkin lymphoma, and solid tumors. All identified M-CT cycles with prophylactic (first 5 days of cycle) FIL, PEG, or SAR were included in the analysis. Patterns of administration and incidence rates of all-cause and neutropenia-related hospitalization were examined on a per-cycle basis. RESULTS In total, 9330 and 8762 patients with cancer, representing 30,264 and 24,215 chemotherapy cycles (28,189 and 22,649 (PEG), 1669 and 1351 (FIL), 406 and 215 (SAR)) from the HIRD(SM) and OptumInsight databases, respectively, were included in the separate database analyses. Both the HIRD(SM) and OptumInsight analysis showed that SAR and FIL prophylaxis had a higher risk of neutropenia-related hospitalization (SAR: OR = 3.48 [95%CI = 2.11, 5.74] and 2.81 [1.62, 4.87]; FIL: 1.78 [1.28, 2.48] and 2.36 [1.82, 3.06], respectively) and all-cause hospitalization (SAR: 2.18 [1.41, 3.36] and 2.41 [1.58, 3.68]; FIL:1.57 [1.25, 1.97] and 1.95 [1.60, 2.38], respectively) vs PEG. LIMITATIONS Medical claims do not contain information about chemotherapy dose, and hospitalizations were not validated against the patient's chart. CONCLUSION In this comparative effectiveness study, use of PEG was associated with a lower risk of neutropenia-related and all-cause hospitalizations compared to use of FIL or SAR prophylaxis.
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Banwo K, Sanni A, Tan H. Technological properties and probiotic potential of Enterococcus faecium strains isolated from cow milk. J Appl Microbiol 2012; 114:229-41. [PMID: 23035976 DOI: 10.1111/jam.12031] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Revised: 08/29/2012] [Accepted: 09/29/2012] [Indexed: 11/29/2022]
Abstract
AIM To identify enterococci from the fermentation of milk for the production of nono, an African fermented dairy product, to determine the technological properties for suitability as starter cultures and safety as probiotics. METHODS AND RESULTS Enterococcus faecium CM4 and Enterococcus faecium 2CM1 were isolated from raw cow's milk. The strains were phenotypically and genotypically identified. Technological properties, safety investigations, in vitro adherence properties and antimicrobial characteristics were carried out. Strong acidification and tolerance to bile salts were recorded. The strains were bile salts hydrolytic positive and no haemolysis. There was no resistance to clinically relevant antibiotics. The strains exhibited adherence to human collagen type IV, human fibrinogen and fibronectin. The bacteriocins were active against Bacillus cereus DSM 2301, Bacillus subtilis ATCC 6633, Micrococcus luteus and Listeria monocytogenes. Bacteriocins were stable at pH 4-9 and on treatment with lipase, catalase, α-amylase and pepsin, while their activity was lost on treatment with other proteases. The bacteriocins produced were heat stable at 100°C for 10 min. The bacteriocin produced by the strains was identified as enterocin A. CONCLUSIONS The E. faecium strains in this study exhibited probiotic activity, and the safety investigations indicate their suitability as good candidates for a starter culture fermentation process. SIGNIFICANCE AND IMPACT OF THE STUDY The use of bacteriocin-producing E. faecium strains as starter cultures in fermented foods is beneficial but, however, their safety investigations as probiotics must be greatly emphasized.
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Tan H, Falcone F, Hussain M, Eljamel S. Dysgeusia as a Presenting Complaint of Vestibular Schwannoma. Skull Base Surg 2012. [DOI: 10.1055/s-0032-1314205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Lin W, Li H, Liu W, Cao L, Tan H, Zhong Z. A randomised trial comparing the CEL-100 videolaryngoscope(TM) with the Macintosh laryngoscope blade for insertion of double-lumen tubes. Anaesthesia 2012; 67:771-6. [PMID: 22540996 DOI: 10.1111/j.1365-2044.2012.07137.x] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We performed a randomised trial comparing the CEL-100 videolaryngoscope(TM) with the Macintosh laryngoscope blade in 170 patients undergoing double-lumen tube placement for thoracic surgery. Compared with the Macintosh laryngoscope blade, use of the CEL-100 resulted in significantly more patients with a Cormack and Lehane Grade-1 laryngeal view (90.4% vs 61.0%, p < 0.001), a higher rate of successful intubation on the first attempt (92.8% vs 79.3%, p = 0.012), a lower median (IQR [range]) intubation difficulty score (0 (0-0 [0-60]) vs 15 (0-30 [0-80]), p < 0.001), a higher incidence of correct positioning of the tube (90.3% vs 79.2%, p = 0.041) and significantly fewer patients requiring external laryngeal pressure (19.3% vs 32.9%, p = 0.046). Median (IQR [range]) time to successful intubation was 45 (38-55 [22-132]) s with the CEL-100 compared with 51 (40-61 [30-160] s using the Macintosh laryngoscope blade. We conclude that the CEL-100 videolaryngoscope is superior to the Macintosh laryngoscope blade for double-lumen tube insertion.
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Wen SW, Xie RH, Tan H, Walker MC, Smith GN, Retnakaran R. Preeclampsia and gestational diabetes mellitus: pre-conception origins? Med Hypotheses 2012; 79:120-5. [PMID: 22541860 DOI: 10.1016/j.mehy.2012.04.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Accepted: 04/03/2012] [Indexed: 02/08/2023]
Abstract
Preeclampsia (PE) and gestational diabetes mellitus (GDM) are two of the most common medical complications of pregnancy, with risks for both mother and child. Like many other antepartum complications, PE and GDM occur only in pregnancy. However, it is not clear if pregnancy itself is the cause of these complications or it these conditions are caused by factors that existed prior to gestation. In this paper, we hypothesize that although the clinical findings of PE and GDM are first noted during pregnancy, the origins of both conditions may actually precede pregnancy. We further hypothesize that pathophysiologic changes underlying PE and GDM are present prior to pregnancy, but remain undetected in the non-gravid state either because pregnancy is the trigger that makes these pathologies become clinically detectable or because there has been limited prospective longitudinal data comparing the pre-gravid and antepartum status of women that go on to develop these conditions. Rigorous prospective cohort studies in which women undergo serial systematic evaluation in the pre-conception period, throughout pregnancy and into the postpartum are ideally needed to test this hypothesis of pre-conception origins of PE and GDM. In this context, we are creating a pre-conception cohort, involving about 5000 couples who plan to have a baby within six months in Liuyang county in the Chinese province of Hunan. Results from this pre-conception cohort program should be able to provide definitive answer to the question of whether the underpinnings of PE and GDM originate prior to pregnancy. Ultimately, the significance of addressing this hypothesis is underscored by its potential implications for targeted interventions that could be designed to (i) prevent the deleterious effects of PE/GDM and (ii) thereby interrupt the vicious cycle of disease that links affected women and their offspring.
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Biela A, Khayat M, Tan H, Kong J, Heine A, Hangauer D, Klebe G. Impact of ligand and protein desolvation on ligand binding to the S1 pocket of thrombin. J Mol Biol 2012; 418:350-66. [PMID: 22366545 DOI: 10.1016/j.jmb.2012.01.054] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Revised: 01/16/2012] [Accepted: 01/30/2012] [Indexed: 11/18/2022]
Abstract
In the present study, we investigate the impact of a tightly bound water molecule on ligand binding in the S1 pocket of thrombin. The S1 pocket contains a deeply buried deprotonated aspartate residue (Asp189) that is, due to its charged state, well hydrated in the uncomplexed state. We systematically studied the importance of this water molecule by evaluating a series of ligands that contains pyridine-type P1 side chains that could potentially alter the binding properties of this water molecule. All of the pyridine derivatives retain the original hydration state albeit sometimes with a slight perturbance. In order to prevent a direct H-bond formation with Asp189, and to create a permanent positive charge on the P1 side chain that is positioned adjacent to the Asp189 carboxylate anion, we methylated the pyridine nitrogen. This methylation resulted in displacement of water but was accompanied by a loss in binding affinity. Quantum chemical calculations of the ligand solvation free energy showed that the positively charged methylpyridinium derivatives suffer a large penalty of desolvation upon binding. Consequently, they have a substantially less favorable enthalpy of binding. In addition to the ligand desolvation penalty, the hydration shell around Asp189 has to be overcome, which is achieved in nearly all pyridinium derivatives. Only for the ortho derivative is a partial population of a water next to Asp189 found. Possibly, the gain of electrostatic interactions between the charged P1 side chain and Asp189 helps to compensate for the desolvation penalty. In all uncharged pyridine derivatives, the solvation shell remains next to Asp189, partly mediating interactions between ligand and protein. In the case of the para-pyridine derivative, a strongly disordered cluster of water sites is observed between ligand and Asp189.
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Chen C, Wang R, Tan H, Shao M. 3.149 AN EXPERIMENTAL STUDY OF ESTABLISHING PD DYSKINESIA MODEL THROUGH COMPLETE DAMAGE TO SUBSTANTIA NIGRA IN RATS. Parkinsonism Relat Disord 2012. [DOI: 10.1016/s1353-8020(11)70865-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Tan H, Chen C, Wu Z, Shao M. 1.038 ANALYSIS OF FACTORS CORRELATED TO CONSTIPATION IN PATIENTS WITH PARKINSON'S DISEASE. Parkinsonism Relat Disord 2012. [DOI: 10.1016/s1353-8020(11)70152-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Anzak A, Pogosyan A, Tan H, Foltynie T, Limousin, P, Zrinzo L, Hariz M, Ashkan K, Thevathasan W, Bogdanovic M, Green A, Aziz T, Brown P. 3.320 INSIGHTS INTO THE MECHANISM OF PARADOXICAL KINESIA FROM SUBTHALAMIC NUCLEUS RECORDINGS IN PARKINSON'S DISEASE. Parkinsonism Relat Disord 2012. [DOI: 10.1016/s1353-8020(11)70954-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Pollick F, Steel W, Tan H, Piwek L, Crabbe F, Ahlstrom U. A New Action Library for Localising Brain Activity Specific to Biological Motion. J Vis 2011. [DOI: 10.1167/11.11.683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Zhu Z, Doss M, Tan H, Feigenberg S, Yu JQ. Inadvertent Intraarterial Injection of 18F-FDG: A Case Report and Literature Review of Hot Forearm and Hot Hand Signs. J Nucl Med Technol 2011; 39:249-51. [PMID: 21865286 DOI: 10.2967/jnmt.111.089011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
124
|
Tan H, Yu J, Ahmed M, Inamoto A, Yager S, Deeter RG. Comparative effectiveness of CSFs for hospitalization risk in real-world oncology practice. J Clin Oncol 2011. [DOI: 10.1200/jco.2011.29.15_suppl.e16531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
|
125
|
Gu J, Liu X, Wang X, Shi H, Tan H, Zhou L, Gu J, Jiang W, Wang Y. Beneficial effect of pioglitazone on the outcome of catheter ablation in patients with paroxysmal atrial fibrillation and type 2 diabetes mellitus. Europace 2011; 13:1256-61. [DOI: 10.1093/europace/eur131] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
|