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McDermott MM, Greenland P, Liu K, Guralnik JM, Criqui MH, Dolan NC, Chan C, Celic L, Pearce WH, Schneider JR, Sharma L, Clark E, Gibson D, Martin GJ. Leg symptoms in peripheral arterial disease: associated clinical characteristics and functional impairment. JAMA 2001; 286:1599-606. [PMID: 11585483 DOI: 10.1001/jama.286.13.1599] [Citation(s) in RCA: 598] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Persons with lower-extremity peripheral arterial disease (PAD) are often asymptomatic or have leg symptoms other than intermittent claudication (IC). OBJECTIVE To identify clinical characteristics and functional limitations associated with a broad range of leg symptoms identified among patients with PAD. DESIGN, SETTING, AND PARTICIPANTS Cross-sectional study of 460 men and women with PAD and 130 without PAD, who were identified consecutively, conducted between October 1998 and January 2000 at 3 Chicago-area medical centers. MAIN OUTCOME MEASURES Ankle-brachial index score of less than 0.90; scores from 6-minute walk, accelerometer-measured physical activity over 7 days, repeated chair raises, standing balance (full tandem stand), 4-m walking velocity, San Diego claudication questionnaire, Geriatric Depression Score Short-Form, and the Walking Impairment Questionnaire. RESULTS All groups with PAD had poorer functioning than participants without PAD. The following values are for patients without IC vs those with IC. Participants in the group with leg pain on exertion and rest (n = 88) had a higher (poorer) score for neuropathy (5.6 vs 3.5; P<.001), prevalence of diabetes mellitus (48.9% vs 26.7%; P<.001), and spinal stenosis (20.8% vs 7.2%; P =.002). The atypical exertional leg pain/carry on group (exertional leg pain other than IC associated with walking through leg pain [n = 41]) and the atypical exertional leg pain/stop group (exertional leg pain other than IC that causes one to stop walking [n = 90]) had better functioning than the IC group. The group without exertional leg pain/inactive (no exertional leg pain in individual who walks </=6 blocks per week [n = 28]) and the leg pain on exertion and rest group had poorer functioning than those with IC. Adjusting for age, sex, race, and comorbidities and compared with IC, participants with atypical exertional leg pain/carry on achieved a greater distance on the 6-minute walk (404.3 vs 328.5 m; P<.001) and were less likely to stop during the 6-minute walk (6.8% vs 36%; P =.002). The group with pain on exertion and rest had a slower time for completing 5 chair raises (13.5 vs 11.9 seconds; P =.009), completed the tandem stand less frequently (37.5% vs 60.0%; P =.004), and had a slower 4-m walking velocity (0.80 vs 0.90 m/s; P<.001). CONCLUSIONS There is a wide range of leg symptoms in persons with PAD beyond that of classic IC. Comorbid disease may contribute to these symptoms in PAD. Functional impairments are found in every PAD symptom group, and the degree of functional limitation varies depending on the type of leg symptom.
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Poirier MA, Xiao W, Macosko JC, Chan C, Shin YK, Bennett MK. The synaptic SNARE complex is a parallel four-stranded helical bundle. NATURE STRUCTURAL BIOLOGY 1998; 5:765-9. [PMID: 9731768 DOI: 10.1038/1799] [Citation(s) in RCA: 390] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The heterotrimeric synaptic soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex, consisting of the synaptic vesicle-associated membrane protein 2 (VAMP2) and presynaptic plasma membrane proteins SNAP-25 (synaptosome-associated protein of 25,000 Mr) and syntaxin 1A, is a critical component of the exocytotic machinery. We have used spin labeling electron paramagnetic resonance spectroscopy to investigate the structural organization of this complex, particularly the two predicted helical domains contributed by SNAP-25. Our results indicate that the N- and C-terminal domains of SNAP-25 are parallel to each other and to the C-terminal domain of syntaxin 1A. Based on these findings, we propose a parallel four-stranded coiled coil model for the structure of the synaptic SNARE complex.
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Gross CA, Chan C, Dombroski A, Gruber T, Sharp M, Tupy J, Young B. The functional and regulatory roles of sigma factors in transcription. COLD SPRING HARBOR SYMPOSIA ON QUANTITATIVE BIOLOGY 1999; 63:141-55. [PMID: 10384278 DOI: 10.1101/sqb.1998.63.141] [Citation(s) in RCA: 286] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Review |
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Gillard J, Ford-Hutchinson AW, Chan C, Charleson S, Denis D, Foster A, Fortin R, Leger S, McFarlane CS, Morton H. L-663,536 (MK-886) (3-[1-(4-chlorobenzyl)-3-t-butyl-thio-5-isopropylindol-2-yl]-2,2 - dimethylpropanoic acid), a novel, orally active leukotriene biosynthesis inhibitor. Can J Physiol Pharmacol 1989; 67:456-64. [PMID: 2548691 DOI: 10.1139/y89-073] [Citation(s) in RCA: 267] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
L-663,536 (3-[1-(4-chlorobenzyl)-3-t-butyl-thio-5-isopropylindol-2-yl]-2, 2-dimethylpropanoic acid) is a potent inhibitor of leukotriene (LT) biosynthesis in intact human polymorphonuclear leukocytes (PMN) (IC50, 2.5 nM). Similarly, L-663,536 inhibited A23187-induced LTB4 formation by rat peripheral blood and elicited PMN. At concentrations where inhibition of leukotriene biosynthesis occurred in human whole blood (1.1 microM), no effect was seen on cyclooxygenase or 12-lipoxygenase, an effect also observed in washed human platelets. The compound had no effect on rat or porcine 5-lipoxygenase indicating that L-663,536 is not a direct 5-lipoxygenase inhibitor. When administered in vivo L-663,536 was a potent inhibitor of antigen-induced dyspnea in inbred rats pretreated with methysergide (ED50, 0.036 mg/kg p.o.) and of Ascaris-induced bronchoconstriction in squirrel monkeys (1 mg/kg p.o.). The compound inhibited leukotriene biosynthesis in vivo in a rat pleurisy model (ED50, 0.2 mg/kg p.o.), an inflamed rat paw model (ED50, 0.8 mg/kg), a model of leukotriene excretion in rat bile following antigen provocation, and a model in the guinea-pig ear where leukotriene synthesis was induced by topical challenge with ionophore A23187 (ED50, 2.5 mg/kg p.o. and 0.6 micrograms topically). The results indicate that L-663,536 is a potent inhibitor of leukotriene biosynthesis both in vitro and in vivo indicating that the compound is suitable for studying the role of leukotrienes in a variety of pathological situations.
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Drees BL, Sundin B, Brazeau E, Caviston JP, Chen GC, Guo W, Kozminski KG, Lau MW, Moskow JJ, Tong A, Schenkman LR, McKenzie A, Brennwald P, Longtine M, Bi E, Chan C, Novick P, Boone C, Pringle JR, Davis TN, Fields S, Drubin DG. A protein interaction map for cell polarity development. J Cell Biol 2001; 154:549-71. [PMID: 11489916 PMCID: PMC2196425 DOI: 10.1083/jcb.200104057] [Citation(s) in RCA: 240] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Many genes required for cell polarity development in budding yeast have been identified and arranged into a functional hierarchy. Core elements of the hierarchy are widely conserved, underlying cell polarity development in diverse eukaryotes. To enumerate more fully the protein-protein interactions that mediate cell polarity development, and to uncover novel mechanisms that coordinate the numerous events involved, we carried out a large-scale two-hybrid experiment. 68 Gal4 DNA binding domain fusions of yeast proteins associated with the actin cytoskeleton, septins, the secretory apparatus, and Rho-type GTPases were used to screen an array of yeast transformants that express approximately 90% of the predicted Saccharomyces cerevisiae open reading frames as Gal4 activation domain fusions. 191 protein-protein interactions were detected, of which 128 had not been described previously. 44 interactions implicated 20 previously uncharacterized proteins in cell polarity development. Further insights into possible roles of 13 of these proteins were revealed by their multiple two-hybrid interactions and by subcellular localization. Included in the interaction network were associations of Cdc42 and Rho1 pathways with proteins involved in exocytosis, septin organization, actin assembly, microtubule organization, autophagy, cytokinesis, and cell wall synthesis. Other interactions suggested direct connections between Rho1- and Cdc42-regulated pathways; the secretory apparatus and regulators of polarity establishment; actin assembly and the morphogenesis checkpoint; and the exocytic and endocytic machinery. In total, a network of interactions that provide an integrated response of signaling proteins, the cytoskeleton, and organelles to the spatial cues that direct polarity development was revealed.
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Masura J, Walsh KP, Thanopoulous B, Chan C, Bass J, Goussous Y, Gavora P, Hijazi ZM. Catheter closure of moderate- to large-sized patent ductus arteriosus using the new Amplatzer duct occluder: immediate and short-term results. J Am Coll Cardiol 1998; 31:878-82. [PMID: 9525563 DOI: 10.1016/s0735-1097(98)00013-8] [Citation(s) in RCA: 237] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVES The aim of this study was to assess the immediate and short-term results of anterograde catheter closure of a moderate- to large-sized patent ductus arteriosus (PDA) using the new self-expandable, respositionable Amplatzer duct occluder (ADO) device. BACKGROUND Transcatheter closure of a PDA using devices or coils is technically challenging and may be accompanied by a 38% incidence of residual shunts. METHODS Twenty-four patients (6 male, 18 female) underwent attempted transcatheter closure of a PDA using the ADO at a median age of 3.8 years (range 0.4 to 48) and a median weight of 15.5 kg (range 6 to 70). The mean PDA diameter at its narrowest segment was 3.7+/-1.5 mm. A 6F long sheath was used for delivery of the ADO. Follow-up evaluation was performed with color flow mapping of the main pulmonary artery within 24 h and at 1 and 3 months after closure. RESULTS Twenty three of the 24 patients had successful device placement. Angiography showed that 7 patients had complete immediate closure, 14 had a trace shunt (foaming through the device with no jet), and 2 had a small residual shunt (with a jet). Within 24 h, color Doppler revealed complete closure in all patients. The unsuccessful attempt was during an initial trial with a prototype that has been modified. The median fluoroscopy time was 13.5 min (range 6.3 to 47). All patients were discharged home the next day. There were no complications. Of the 23 patients, 21 completed the 1-month follow-up, all (95% confidence interval [CI] 86% to 100%) with complete closure, and 18 of 23 patients completed the 3-month follow-up, also all (95% CI 83% to 100%) with complete closure. CONCLUSIONS Anterograde transcatheter closure using the new ADO is an effective therapy for patients with a PDA diameter up to 6 mm. Further clinical trials are underway.
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Edwards A, Pang N, Shiu V, Chan C. The understanding of spirituality and the potential role of spiritual care in end-of-life and palliative care: a meta-study of qualitative research. Palliat Med 2010; 24:753-70. [PMID: 20659977 DOI: 10.1177/0269216310375860] [Citation(s) in RCA: 237] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Spirituality and spiritual care are gaining increasing attention but their potential contribution to palliative care remains unclear. The aim of this study was to synthesize qualitative literature on spirituality and spiritual care at the end of life using a systematic ('meta-study') review. Eleven patient articles and eight with healthcare providers were included, incorporating data from 178 patients and 116 healthcare providers, mainly from elderly White and Judaeo-Christian origin patients with cancer. Spirituality principally focused on relationships, rather than just meaning making, and was given as a relationship. Spirituality was a broader term that may or may not encompass religion. A 'spirit to spirit' framework for spiritual care-giving respects individual personhood. This was achieved in the way physical care was given, by focusing on presence, journeying together, listening, connecting, creating openings, and engaging in reciprocal sharing. Affirmative relationships supported patients, enabling them to respond to their spiritual needs. The engagement of family caregivers in spiritual care appears underutilized. Relationships formed an integral part of spirituality as they were a spiritual need, caused spiritual distress when broken and were the way spiritual care was given. Barriers to spiritual care include lack of time, personal, cultural or institutional factors, and professional educational needs. By addressing these, we may make an important contribution to the improvement of patient care towards the end of life.
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Meta-Analysis |
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Ahn NG, Weiel JE, Chan CP, Krebs EG. Identification of multiple epidermal growth factor-stimulated protein serine/threonine kinases from Swiss 3T3 cells. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(19)38423-6] [Citation(s) in RCA: 209] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Chan CP, Siu KL, Chin KT, Yuen KY, Zheng B, Jin DY. Modulation of the unfolded protein response by the severe acute respiratory syndrome coronavirus spike protein. J Virol 2006; 80:9279-87. [PMID: 16940539 PMCID: PMC1563899 DOI: 10.1128/jvi.00659-06] [Citation(s) in RCA: 192] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Perturbation of the function of endoplasmic reticulum (ER) causes stress leading to the activation of cell signaling pathways known as the unfolded protein response (UPR). Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) uses ER as a site for synthesis and processing of viral proteins. In this report, we demonstrate that infection with SARS-CoV induces the UPR in cultured cells. A comparison with M, E, and NSP6 proteins indicates that SARS-CoV spike (S) protein sufficiently induces transcriptional activation of several UPR effectors, including glucose-regulated protein 78 (GRP78), GRP94, and C/EBP homologous protein. A substantial amount of S protein accumulates in the ER. The expression of S protein exerts different effects on the three major signaling pathways of the UPR. Particularly, it induces GRP78/94 through PKR-like ER kinase but has no influence on activating transcription factor 6 or X box-binding protein 1. Taken together, our findings suggest that SARS-CoV S protein specifically modulates the UPR to facilitate viral replication.
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Research Support, Non-U.S. Gov't |
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Chaparro C, Maurer J, Gutierrez C, Krajden M, Chan C, Winton T, Keshavjee S, Scavuzzo M, Tullis E, Hutcheon M, Kesten S. Infection with Burkholderia cepacia in cystic fibrosis: outcome following lung transplantation. Am J Respir Crit Care Med 2001; 163:43-8. [PMID: 11208624 DOI: 10.1164/ajrccm.163.1.9811076] [Citation(s) in RCA: 185] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
As a result of concern over excessive mortality after lung transplantation, many transplant programs refuse to accept cystic fibrosis (CF) patients infected with Burkholderia cepacia. As a significant proportion of patients with CF in our community are infected with this organism, we have continued to provide lung transplantation as an option. A retrospective review was conducted of medical records of all patients with CF transplanted between March 1988 and September 1996. Fifty-six transplant procedures were performed in 53 recipients with CF between March 1988 and September 1996. Twenty-eight had B. cepacia isolated pretransplant and 25 remaining positive post-transplant. Of the 53 recipients, 19 have died (15 of 28 [54%] B. cepacia positive and 4 of 25 [16%] B. cepacia negative). B. cepacia was responsible for or involved in 14 deaths. Nine of the deaths occurred in the first 3 mo post-transplantation. One-year survival was 67% for B. cepacia positive patients and 92% for B. cepacia negative patients. Recent modifications in antimicrobial and immunosuppressive therapy since 1995 have resulted in no deaths early post-transplant in the last five patients transplanted. We conclude that early mortality in patients with CF infected with B. cepacia is significantly higher than in those not infected with B. cepacia. Modifications in post-transplant medical therapy may improve outcome.
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Jones M, Chan C. The pain and discomfort experienced during orthodontic treatment: a randomized controlled clinical trial of two initial aligning arch wires. Am J Orthod Dentofacial Orthop 1992; 102:373-81. [PMID: 1456222 DOI: 10.1016/0889-5406(92)70054-e] [Citation(s) in RCA: 183] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A randomized controlled clinical trial was performed to compare the nature, prevalence, intensity, and duration of pain related to the use of a relatively recently developed superelastic arch wire and a more traditional multistranded steel arch wire. Other factors likely to influence the pain experience were also investigated. Forty-three subjects participated in the study, the pain response being assessed by each of the visual analogue scales, the questionnaires, and an analgesic consumption record. In 18 of the 43 subjects a standardized preliminary dental extraction procedure was used as a control. Subsequent to the random allocation of an initial arch wire in 43 patients, 22 of them underwent a second arch wire in the opposing arch, the wire again being determined by random allocation. It was found that the prevalence, intensity, and duration of pain after the insertion of the two types of wire was similar but much greater than in the postextraction control phase. The pain score peaked on the morning after the placement of the arch wire, lasting typically for 5 to 6 days. The pain and discomfort experienced after the insertion of the second arch wire was similar to that of the first, no conditioning response being evident. Overall a diurnal variation was found with a tendency to an increase in pain in the evenings and nights, although this did not greatly affect sleep. The pain response was found to be highly and consistently subjective, not related to the dental arch, crowding, sex, or social class; however, a statistically significant association was found between the age and the pain experienced.
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Akerib DS, Alsum S, Araújo HM, Bai X, Bailey AJ, Balajthy J, Beltrame P, Bernard EP, Bernstein A, Biesiadzinski TP, Boulton EM, Bramante R, Brás P, Byram D, Cahn SB, Carmona-Benitez MC, Chan C, Chiller AA, Chiller C, Currie A, Cutter JE, Davison TJR, Dobi A, Dobson JEY, Druszkiewicz E, Edwards BN, Faham CH, Fiorucci S, Gaitskell RJ, Gehman VM, Ghag C, Gibson KR, Gilchriese MGD, Hall CR, Hanhardt M, Haselschwardt SJ, Hertel SA, Hogan DP, Horn M, Huang DQ, Ignarra CM, Ihm M, Jacobsen RG, Ji W, Kamdin K, Kazkaz K, Khaitan D, Knoche R, Larsen NA, Lee C, Lenardo BG, Lesko KT, Lindote A, Lopes MI, Manalaysay A, Mannino RL, Marzioni MF, McKinsey DN, Mei DM, Mock J, Moongweluwan M, Morad JA, Murphy ASJ, Nehrkorn C, Nelson HN, Neves F, O'Sullivan K, Oliver-Mallory KC, Palladino KJ, Pease EK, Phelps P, Reichhart L, Rhyne C, Shaw S, Shutt TA, Silva C, Solmaz M, Solovov VN, Sorensen P, Stephenson S, Sumner TJ, Szydagis M, Taylor DJ, Taylor WC, Tennyson BP, Terman PA, Tiedt DR, To WH, Tripathi M, Tvrznikova L, Uvarov S, Verbus JR, Webb RC, White JT, Whitis TJ, Witherell MS, Wolfs FLH, Xu J, Yazdani K, Young SK, et alAkerib DS, Alsum S, Araújo HM, Bai X, Bailey AJ, Balajthy J, Beltrame P, Bernard EP, Bernstein A, Biesiadzinski TP, Boulton EM, Bramante R, Brás P, Byram D, Cahn SB, Carmona-Benitez MC, Chan C, Chiller AA, Chiller C, Currie A, Cutter JE, Davison TJR, Dobi A, Dobson JEY, Druszkiewicz E, Edwards BN, Faham CH, Fiorucci S, Gaitskell RJ, Gehman VM, Ghag C, Gibson KR, Gilchriese MGD, Hall CR, Hanhardt M, Haselschwardt SJ, Hertel SA, Hogan DP, Horn M, Huang DQ, Ignarra CM, Ihm M, Jacobsen RG, Ji W, Kamdin K, Kazkaz K, Khaitan D, Knoche R, Larsen NA, Lee C, Lenardo BG, Lesko KT, Lindote A, Lopes MI, Manalaysay A, Mannino RL, Marzioni MF, McKinsey DN, Mei DM, Mock J, Moongweluwan M, Morad JA, Murphy ASJ, Nehrkorn C, Nelson HN, Neves F, O'Sullivan K, Oliver-Mallory KC, Palladino KJ, Pease EK, Phelps P, Reichhart L, Rhyne C, Shaw S, Shutt TA, Silva C, Solmaz M, Solovov VN, Sorensen P, Stephenson S, Sumner TJ, Szydagis M, Taylor DJ, Taylor WC, Tennyson BP, Terman PA, Tiedt DR, To WH, Tripathi M, Tvrznikova L, Uvarov S, Verbus JR, Webb RC, White JT, Whitis TJ, Witherell MS, Wolfs FLH, Xu J, Yazdani K, Young SK, Zhang C. Results from a Search for Dark Matter in the Complete LUX Exposure. PHYSICAL REVIEW LETTERS 2017; 118:021303. [PMID: 28128598 DOI: 10.1103/physrevlett.118.021303] [Show More Authors] [Citation(s) in RCA: 175] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Indexed: 06/06/2023]
Abstract
We report constraints on spin-independent weakly interacting massive particle (WIMP)-nucleon scattering using a 3.35×10^{4} kg day exposure of the Large Underground Xenon (LUX) experiment. A dual-phase xenon time projection chamber with 250 kg of active mass is operated at the Sanford Underground Research Facility under Lead, South Dakota (USA). With roughly fourfold improvement in sensitivity for high WIMP masses relative to our previous results, this search yields no evidence of WIMP nuclear recoils. At a WIMP mass of 50 GeV c^{-2}, WIMP-nucleon spin-independent cross sections above 2.2×10^{-46} cm^{2} are excluded at the 90% confidence level. When combined with the previously reported LUX exposure, this exclusion strengthens to 1.1×10^{-46} cm^{2} at 50 GeV c^{-2}.
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Hughes W, Leoung G, Kramer F, Bozzette SA, Safrin S, Frame P, Clumeck N, Masur H, Lancaster D, Chan C. Comparison of atovaquone (566C80) with trimethoprim-sulfamethoxazole to treat Pneumocystis carinii pneumonia in patients with AIDS. N Engl J Med 1993; 328:1521-7. [PMID: 8479489 DOI: 10.1056/nejm199305273282103] [Citation(s) in RCA: 174] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
BACKGROUND Both trimethoprim-sulfamethoxazole and pentamidine are effective as treatments for Pneumocystis carinii pneumonia, but adverse effects frequently limit their use. Atovaquone (566C80) is a new hydroxynaphthoquinone with activity against P. carinii. METHODS We conducted a double-blind, multicenter study in patients with the acquired immunodeficiency syndrome and mild or moderately severe P. carinii pneumonia. They were randomly assigned to 21 days of orally administered treatment three times daily with either atovaquone (750 mg) or trimethoprim (320 mg) plus sulfamethoxazole (1600 mg). RESULTS Of the 322 patients with histologically confirmed P. carinii pneumonia, 160 received atovaquone and 162 received trimethoprim-sulfamethoxazole. Of those who could be evaluated for therapeutic efficacy, 28 of 138 patients given atovaquone (20 percent) and 10 of 146 patients given trimethoprim-sulfamethoxazole (7 percent) did not respond (P = 0.002). Treatment-limiting adverse effects required a change of therapy in 11 patients in the atovaquone group (7 percent) and 33 patients in the trimethoprim-sulfamethoxazole group (20 percent) (P = 0.001). Therapy involving only the initial drug was successful and free of adverse effects in 62 percent of those assigned to atovaquone and 64 percent of those assigned to trimethoprim-sulfamethoxazole. Within four weeks of the completion of treatment, there were 11 deaths in the atovaquone group (4 due to P. carinii pneumonia) and 1 death in the trimethoprim-sulfamethoxazole group (P = 0.003). Diarrhea at entry was associated with lower plasma drug concentrations (P = 0.009), therapeutic failure (P < 0.001), and death (P < 0.001) in the atovaquone group but not in the trimethoprim-sulfamethoxazole group. CONCLUSIONS For the treatment of P. carinii pneumonia, atovaquone is less effective than trimethoprim-sulfamethoxazole, but it has fewer treatment-limiting adverse effects.
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Cribier A, Korsatz L, Koning R, Rath P, Gamra H, Stix G, Merchant S, Chan C, Letac B. Improved myocardial ischemic response and enhanced collateral circulation with long repetitive coronary occlusion during angioplasty: a prospective study. J Am Coll Cardiol 1992; 20:578-86. [PMID: 1512336 DOI: 10.1016/0735-1097(92)90011-b] [Citation(s) in RCA: 174] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVES The goal of the study was to evaluate the progressive increase in ischemic threshold with multiple sequential transient coronary occlusions and to assess the role of the collateral circulation in adaptation to ischemia. BACKGROUND It has been observed that the duration of balloon inflations during coronary angioplasty can be gradually prolonged during subsequent dilations with a reduction in patient symptoms and diminished ischemic electrocardiographic (ECG) changes. Although the mechanism has not been fully explained, recruitment of coronary collateral circulation induced by repeated coronary occlusion has been reported. The stimuli for recruitment and the natural history of coronary collateral circulation are not understood. METHODS Seventeen patients with isolated stenosis of the left anterior descending coronary artery and a normal left ventricle were enrolled. Angioplasty consisted of five successive prolonged inflations. Sequential changes in clinical, intracoronary ECG and left ventricular indexes of myocardial ischemia were examined. Coronary collateral channels were evaluated during balloon inflations by ipsilateral and contralateral injections of contrast medium and hemodynamically by occlusion pressure. RESULTS An improved tolerance to myocardial ischemia with repetitive coronary occlusions was demonstrated by a significant reduction of angina, ST segment deviation, left ventricular filling pressure and less impairment of ejection fraction. Left ventricular wall motion abnormalities remained unchanged. Collateral angiographic grade did not change in 7 patients and increased in 10. CONCLUSIONS This study confirms a progressive adaptation of myocardial ischemia to repetitive coronary occlusions and supports the concept that sequential episodes of myocardial ischemia are a stimulating factor for the recruitment of collateral channels in humans. These results also suggest that enhancement of recruitable collateral circulation might be an underlying mechanism of myocardial ischemic preconditioning.
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Malek TR, Ortega G, Chan C, Kroczek RA, Shevach EM. Role of Ly-6 in lymphocyte activation. II. Induction of T cell activation by monoclonal anti-Ly-6 antibodies. J Exp Med 1986; 164:709-22. [PMID: 3489060 PMCID: PMC2188391 DOI: 10.1084/jem.164.3.709] [Citation(s) in RCA: 163] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The Ly-6 locus controls the expression and/or encodes for alloantigenic specificities found primarily on subpopulations of murine T and B lymphocytes. We have recently identified and characterized a new rat mAb, D7, that recognizes a nonpolymorphic Ly-6 specificity. After crosslinking by anti-Ig reagents or by Fc receptor-bearing accessory cells, mAb D7 could induce IL-2 production from T cell hybridomas, and in the presence of PMA could trigger a vigorous proliferative response in resting peripheral T cells. The addition of mAb D7 to cultures of antigen- and alloantigen-, but not mitogen-stimulated T cells resulted in a marked augmentation of the proliferative response. A number of other well-characterized mAbs to Ly-6 locus products could also stimulate a T cell proliferative response after crosslinking by anti-Ig and in the presence of PMA. These results strongly suggest that Ly-6 molecules may play a critical role in the T cell activation cascade, either as receptors for an unidentified soluble or cell-associated ligand or as transducing molecules that modulate signals initiated by antigen stimulation of the T3-Ti complex.
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research-article |
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Goldkorn T, Balaban N, Matsukuma K, Chea V, Gould R, Last J, Chan C, Chavez C. EGF-Receptor phosphorylation and signaling are targeted by H2O2 redox stress. Am J Respir Cell Mol Biol 1998; 19:786-98. [PMID: 9806743 DOI: 10.1165/ajrcmb.19.5.3249] [Citation(s) in RCA: 154] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Inflammation of the respiratory tract is associated with the production of reactive oxygen species, such as hydrogen peroxide (H2O2) and superoxide (O2-), which contribute extensively to lung injury in diseases of the respiratory tract. The mechanisms and target molecules of these oxidants are mainly unknown but may involve modifications of growth-factor receptors. We have shown that H2O2 induces epidermal growth factor (EGF)-receptor tyrosine phosphorylation in intact cells as well as in membranes of A549 lung epithelial cells. On the whole, total phosphorylation of the EGF receptor induced by H2O2 was lower than that induced by the ligand EGF. Phosphorylation was confined to tyrosine residues and was inhibited by addition of genistein, indicating that it was due to the activation of protein tyrosine kinase (PTK). Phosphoamino acid analysis revealed that although the ligand, EGF, enhanced the phosphorylation of serine, threonine, and tyrosine residues, H2O2 preferentially enhanced tyrosine phosphorylation of the EGF receptor. Serine and threonine phosphorylation did not occur, and the turnover rate of the EGF receptor was slower after H2O2 exposure. Selective H2O2-mediated phosphorylation of tyrosine residues on the EGF receptor was sufficient to activate phosphorylation of an SH2-group-bearing substrate, phospholipase C-gamma (PLC-gamma), but did not increase mitogen-activated protein (MAP) kinase activity. Moreover, H2O2 exposure decreased protein kinase C (PKC)-alpha activity by causing translocation of PKC-alpha from the membrane to the cytoplasm. These studies provide novel insights into the capacity of a reactive oxidant, such as H2O2, to modulate EGF-receptor function and its downstream signaling. The H2O2-induced increase in tyrosine phosphorylation of the EGF receptor, and the receptor's slower rate of turnover and altered downstream phosphorylation signals may represent a mechanism by which EGF-receptor signaling can be modulated during inflammatory processes, thereby affecting cell proliferation and thus having implications in wound repair or tumor formation.
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Chen CL, Hsieh FC, Lieblein JC, Brown J, Chan C, Wallace JA, Cheng G, Hall BM, Lin J. Stat3 activation in human endometrial and cervical cancers. Br J Cancer 2007; 96:591-9. [PMID: 17311011 PMCID: PMC2360038 DOI: 10.1038/sj.bjc.6603597] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The activation of signal transducer and activator of transcription 3 (Stat3) has been implicated in the oncogenesis of cancer and is regarded as a novel target for cancer therapy. Stat3 is classified as a proto-oncogene, because an activated form of Stat3 can mediate oncogenic transformation in cultured cells and tumour formation in nude mice. The constitutive activation of Stat3 has been frequently detected in various types of human cancers. However, the constitutive activation of Stat3 in endometrial and cervical cancers has not been studied. We examined tyrosine phosphorylation of Stat3 (activated form of Stat3) in multiple endometrial and cervical cancer tissues using tissue microarray slides as well as cancer cell lines to explore the possible activation of Stat3. Our results indicated that elevated phosphorylation of Stat3 was detected in cervical and endometrial cancer cell lines. Our results also showed that elevated levels of phosphorylation of Stat3 protein were detected in the endometrial and cervical cancer specimens. This is the first study to demonstrate that Stat3 is activated in human endometrial and cervical cancer tissues. Immunohistochemical staining showed that activated Stat3 is associated with increased expression of downstream antiapoptotic genes, Bcl-xL, survivin, and Mcl-1 in these tissues. Expression of a dominant-negative Stat3 mutant using adenovirus-mediated gene transfer inhibited cell growth and induced apoptosis in HeLa and SiHa cervical cancer cell lines expressing elevated levels of Stat3 phosphorylation. Further, a JAK/Stat3 small molecular inhibitor, JSI-124, induced apoptosis more selectively in HeLa and SiHa cancer cell lines than Ishikawa cell line without elevated levels of Stat3 phosphorylation. These results indicate that Stat3 is activated in human endometrial and cervical cancers and the inhibition of constitutive Stat3 signaling may be an effective target for cancer intervention in these two cancers.
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Gunter KC, Germain RN, Kroczek RA, Saito T, Yokoyama WM, Chan C, Weiss A, Shevach EM. Thy-1-mediated T-cell activation requires co-expression of CD3/Ti complex. Nature 1987; 326:505-7. [PMID: 3104795 DOI: 10.1038/326505a0] [Citation(s) in RCA: 136] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In addition to monoclonal antibodies against the CD3 (T3)-T-cell antigen receptor (CD3/Ti) complex, several other monoclonals directed towards distinct cell surface structures on human (CD2 (T11) and Tp44) and murine (Thy-1, TAP, and Ly-6) T lymphocytes are capable of activating T cells. It has been proposed that such structures may function as alternative pathways of stimulation. To examine directly whether any relationship exists between Thy-1-dependent activation phenomena and T-cell activation mediated through the CD3/Ti complex, we have transfected several CD3/Ti- variants of the human T-cell line Jurkat with the murine Thy-1.2 gene. Our data indicate that in CD3/Ti-, Thy-1.2+ transfectants, monoclonal antibodies against Thy-1.2 can induce a rise in cytoplasmic free calcium ([Ca2+]i), but fail to stimulate interleukin-2 (IL-2) production. The only defect in these variant cell lines responsible for the inability to produce IL-2 in response to Thy-1 stimulation was in the expression of the CD3/Ti complex, because replacement of defective Ti alpha- or beta-chain genes reconstributed both surface expression of CD3/Ti and responsiveness to Thy-1 in the IL-2 production assay.
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Winey M, Hoyt MA, Chan C, Goetsch L, Botstein D, Byers B. NDC1: a nuclear periphery component required for yeast spindle pole body duplication. J Biophys Biochem Cytol 1993; 122:743-51. [PMID: 8349727 PMCID: PMC2119589 DOI: 10.1083/jcb.122.4.743] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The spindle pole body (SPB) of Saccharomyces cerevisiae serves as the centrosome in this organism, undergoing duplication early in the cell cycle to generate the two poles of the mitotic spindle. The conditional lethal mutation ndc1-1 has previously been shown to cause asymmetric segregation, wherein all the chromosomes go to one pole of the mitotic spindle (Thomas, J. H., and D. Botstein. 1986. Cell. 44:65-76). Examination by electron microscopy of mutant cells subjected to the nonpermissive temperature reveals a defect in SPB duplication. Although duplication is seen to occur, the nascent SPB fails to undergo insertion into the nuclear envelope. The parental SPB remains functional, organizing a monopolar spindle to which all the chromosomes are presumably attached. Order-of-function experiments reveal that the NDC1 function is required in G1 after alpha-factor arrest but before the arrest caused by cdc34. Molecular analysis shows that the NDC1 gene is essential and that it encodes a 656 amino acid protein (74 kD) with six or seven putative transmembrane domains. This evidence for membrane association is further supported by immunofluorescent localization of the NDC1 product to the vicinity of the nuclear envelope. These findings suggest that the NDC1 protein acts within the nuclear envelope to mediate insertion of the nascent SPB.
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McGurk M, Chan C, Jones J, O'regan E, Sherriff M. Delay in diagnosis and its effect on outcome in head and neck cancer. Br J Oral Maxillofac Surg 2005; 43:281-4. [PMID: 15993279 DOI: 10.1016/j.bjoms.2004.01.016] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2003] [Accepted: 01/06/2004] [Indexed: 12/16/2022]
Abstract
We examined the records of two cohorts of patients who were seen from 1960 to 1999 with a diagnosis of squamous cell carcinoma (SCC) of the mouth and throat, one series being retrospective (n=400) and the other prospective (n=213) to find out about delays in diagnosis. The median delay in both cohorts was 3 months and the patients were responsible for the delay in most cases (n=319, 81% and n=160, 78%, respectively). Half the patients in each cohort had delayed diagnoses (n=217, 54% and n=119, 56%, respectively) and similar percentages (n=110, 53% and n=172, 47%) presented with advanced disease (stage III or IV). These were not the same patients for there was no correlation between delay and stage or survival. Logistic regression analysis showed that non-white race (p=0.01) and high-grade histology (p=0.002) predicted advanced disease. The proportion of patients presenting with advanced disease had not changed in 40 years despite public education. We suggest that some tumours may be silent and that initial symptoms do not reliably predict early disease.
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Chang MC, Ho YS, Lee PH, Chan CP, Lee JJ, Hahn LJ, Wang YJ, Jeng JH. Areca nut extract and arecoline induced the cell cycle arrest but not apoptosis of cultured oral KB epithelial cells: association of glutathione, reactive oxygen species and mitochondrial membrane potential. Carcinogenesis 2001; 22:1527-35. [PMID: 11532876 DOI: 10.1093/carcin/22.9.1527] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
There are 600 million betel quid (BQ) chewers in the world. BQ chewing is a major etiologic factor of oral cancer. Areca nut (AN) and arecoline may inhibit the growth of oral mucosal fibroblasts (OMF) and keratinocytes. In this study, AN extract (100-800 microg/ml) and arecoline (20-120 microM) inhibited the growth of oral KB cells by 36-90 and 15-75%, respectively. Exposure to arecoline (> 0.2 mM) for 24 h induced G(2)/M cell cycle arrest of OMF and KB cells. Areca nut extract (> 400 microg/ml) also induced G(2)/M arrest of KB cells, being preceded by S-phase arrest at 7-h of exposure. No evident sub-G(0)/G(1) peak was noted. Marked retraction and intracellular vacuoles formation of OMF and KB cells were observed. Glutathione (GSH) level, mitochondrial membrane potential (Deltabetam) and H(2)O(2) production of KB cells were measured by flow cytometry. GSH level [indicated by 5-chloromethyl-fluorescein (CMF) fluorescence] was depleted by 24-h exposure of KB cells to arecoline (0.4-1.2 mM) and AN extract (800-1200 microg/ml), with increasing the percentage of cells in low CMF fluorescence. By contrast, arecoline (0.1-1.2 mM) and AN extract (800-1200 microg/ml) induced decreasing and increasing H(2)O(2) production (by 2',7'-dichloro- fluorescein fluorescence), respectively. Hyperpolarization of Deltabetam (increasing of rhodamine uptake) was noted by 24-h exposure of KB cells to arecoline (0.4-1.2 mM) and AN extract (800-1200 microg/ml). AN extract (100- 1200 microg/ml) and arecoline (0.1-1.2 mM) induced little DNA fragmentation on KB cells within 24 h. These results indicate that AN ingredients are crucial in the pathogenesis of oral submucous fibrosis (OSF) and oral cancer by differentially inducing the dysregulation of cell cycle control, Deltabetam, GSH level and intracellular H(2)O(2) production, these events being not coupled with cellular apoptosis.
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Akerib DS, Araújo HM, Bai X, Bailey AJ, Balajthy J, Bedikian S, Bernard E, Bernstein A, Bolozdynya A, Bradley A, Byram D, Cahn SB, Carmona-Benitez MC, Chan C, Chapman JJ, Chiller AA, Chiller C, Clark K, Coffey T, Currie A, Curioni A, Dazeley S, de Viveiros L, Dobi A, Dobson J, Dragowsky EM, Druszkiewicz E, Edwards B, Faham CH, Fiorucci S, Flores C, Gaitskell RJ, Gehman VM, Ghag C, Gibson KR, Gilchriese MGD, Hall C, Hanhardt M, Hertel SA, Horn M, Huang DQ, Ihm M, Jacobsen RG, Kastens L, Kazkaz K, Knoche R, Kyre S, Lander R, Larsen NA, Lee C, Leonard DS, Lesko KT, Lindote A, Lopes MI, Lyashenko A, Malling DC, Mannino R, McKinsey DN, Mei DM, Mock J, Moongweluwan M, Morad J, Morii M, Murphy ASJ, Nehrkorn C, Nelson H, Neves F, Nikkel JA, Ott RA, Pangilinan M, Parker PD, Pease EK, Pech K, Phelps P, Reichhart L, Shutt T, Silva C, Skulski W, Sofka CJ, Solovov VN, Sorensen P, Stiegler T, O'Sullivan K, Sumner TJ, Svoboda R, Sweany M, Szydagis M, Taylor D, Tennyson B, Tiedt DR, Tripathi M, Uvarov S, Verbus JR, Walsh N, Webb R, White JT, White D, Witherell MS, Wlasenko M, Wolfs FLH, et alAkerib DS, Araújo HM, Bai X, Bailey AJ, Balajthy J, Bedikian S, Bernard E, Bernstein A, Bolozdynya A, Bradley A, Byram D, Cahn SB, Carmona-Benitez MC, Chan C, Chapman JJ, Chiller AA, Chiller C, Clark K, Coffey T, Currie A, Curioni A, Dazeley S, de Viveiros L, Dobi A, Dobson J, Dragowsky EM, Druszkiewicz E, Edwards B, Faham CH, Fiorucci S, Flores C, Gaitskell RJ, Gehman VM, Ghag C, Gibson KR, Gilchriese MGD, Hall C, Hanhardt M, Hertel SA, Horn M, Huang DQ, Ihm M, Jacobsen RG, Kastens L, Kazkaz K, Knoche R, Kyre S, Lander R, Larsen NA, Lee C, Leonard DS, Lesko KT, Lindote A, Lopes MI, Lyashenko A, Malling DC, Mannino R, McKinsey DN, Mei DM, Mock J, Moongweluwan M, Morad J, Morii M, Murphy ASJ, Nehrkorn C, Nelson H, Neves F, Nikkel JA, Ott RA, Pangilinan M, Parker PD, Pease EK, Pech K, Phelps P, Reichhart L, Shutt T, Silva C, Skulski W, Sofka CJ, Solovov VN, Sorensen P, Stiegler T, O'Sullivan K, Sumner TJ, Svoboda R, Sweany M, Szydagis M, Taylor D, Tennyson B, Tiedt DR, Tripathi M, Uvarov S, Verbus JR, Walsh N, Webb R, White JT, White D, Witherell MS, Wlasenko M, Wolfs FLH, Woods M, Zhang C. First results from the LUX dark matter experiment at the Sanford underground research facility. PHYSICAL REVIEW LETTERS 2014; 112:091303. [PMID: 24655239 DOI: 10.1103/physrevlett.112.091303] [Show More Authors] [Citation(s) in RCA: 116] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Indexed: 06/03/2023]
Abstract
The Large Underground Xenon (LUX) experiment is a dual-phase xenon time-projection chamber operating at the Sanford Underground Research Facility (Lead, South Dakota). The LUX cryostat was filled for the first time in the underground laboratory in February 2013. We report results of the first WIMP search data set, taken during the period from April to August 2013, presenting the analysis of 85.3 live days of data with a fiducial volume of 118 kg. A profile-likelihood analysis technique shows our data to be consistent with the background-only hypothesis, allowing 90% confidence limits to be set on spin-independent WIMP-nucleon elastic scattering with a minimum upper limit on the cross section of 7.6 × 10(-46) cm(2) at a WIMP mass of 33 GeV/c(2). We find that the LUX data are in disagreement with low-mass WIMP signal interpretations of the results from several recent direct detection experiments.
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Chan C, Yin H, Garforth J, McKie JH, Jaouhari R, Speers P, Douglas KT, Rock PJ, Yardley V, Croft SL, Fairlamb AH. Phenothiazine inhibitors of trypanothione reductase as potential antitrypanosomal and antileishmanial drugs. J Med Chem 1998; 41:148-56. [PMID: 9457238 DOI: 10.1021/jm960814j] [Citation(s) in RCA: 110] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Given the role of trypanothione in the redox defenses of pathogenic trypanosomal and leishmanial parasites, in contrast to glutathione for their mammalian hosts, selective inhibitors of trypanothione reductase are potential drug leads against trypanosomiasis and leishmaniasis. In the present study, the rational drug design approach was used to discover tricyclic neuroleptic molecular frameworks as lead structures for the development of inhibitors, selective for trypanothione reductase over host glutathione reductase. From a homology-modeled structure for trypanothione reductase, replaced in the later stages of the study by the X-ray coordinates for the enzyme from Crithidia fasciculata, a series of inhibitors based on phenothiazine was designed. These were shown to be reversible inhibitors of trypanothione reductase from Trypanosoma cruzi, linearly competitive with trypanothione as substrate and noncompetitive with NADPH, consistent with ping-pong bi bi kinetics. Analogues, synthesized to define structure-activity relationships for the active site, included N-acylpromazines, 2-substituted phenothiazines, and trisubstituted promazines. Analysis of Ki and I50 data, on the basis of calculated log P and molar refractivity values, provided evidence of a specially favored fit of small 2-substituents (especially 2-chloro and 2-trifluoromethyl), with a remote hydrophobic patch on the enzyme accessible for larger, hydrophobic 2-substituents. There was also evidence of an additional hydrophobic enzymic region available to suitable N-substituents of the promazine nucleus. Ki data also indicated that the phenothiazine nucleus can adopt more than one inhibitory orientation in its binding site. Selected compounds were tested for in vitro activity against Trypanosoma brucei, T. cruzi, and Leishmania donovani, with selective activities in the micromolar range being determined for a number of them.
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Madill J, Gutierrez C, Grossman J, Allard J, Chan C, Hutcheon M, Keshavjee SH. Nutritional assessment of the lung transplant patient: body mass index as a predictor of 90-day mortality following transplantation. J Heart Lung Transplant 2001; 20:288-96. [PMID: 11257554 DOI: 10.1016/s1053-2498(00)00315-6] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND It is well documented that malnourished and/or obese surgical patients have increased morbidity and mortality post-operatively. Only a few studies investigating the effect of nutritional status on mortality are available pertaining to the transplant population. Since limited data are available on the nutritional status and its effects on mortality in the lung transplant population, we sought to ascertain whether there is an association between mortality and preoperative nutritional status. METHODS We examined mortality during the first 3 months after transplantation. Patients were grouped by body mass index (BMI) categories as < 17 kg/m(2), 17 to < 20 kg/m(2), 20 to 25 kg/m(2) (reference group), > 25 to 27 kg/m(2), and > 27 kg/m(2). Additional risk factors retrieved from the pre-transplant records included age, gender, diagnosis, energy requirements, protein requirements, protein and caloric intake, and weight history. Logistic regression for univariate and multivariate analysis for mortality used recipient age, gender, disease category, pre-transplant cytomegalovirus (CMV) serology, transplant type (single or bilateral), and donor age, gender, and CMV serology. RESULTS The likelihood estimates or odds ratios (ORs) of the risk of death within 90 days of lung transplantation for the BMI categories compared to the reference group were 3.7 for BMI < 17 kg/m(2) (p = 0.085), 1.6 for BMI < 17 to 20 kg/m(2) (p = 0.455), 3.5 for BMI > 25 to 27 kg/m(2) (p = 0.069), and 5.0 for BMI > 27 kg/m(2) (p = 0.003). CONCLUSIONS In patients with a pre-transplant BMI < 17 kg/m(2) or > 25 kg/m(2) the risk of dying within 90 days post-transplant was increased. In patients with a pre-transplant BMI of > 27 kg/m(2) the risk was significantly higher in than the reference group.
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Ho SC, Chan SG, Yip YB, Cheng A, Yi Q, Chan C. Menopausal symptoms and symptom clustering in Chinese women. Maturitas 1999; 33:219-27. [PMID: 10656500 DOI: 10.1016/s0378-5122(99)00056-0] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVES this paper aims to report the prevalence of symptoms in the Hong Kong Chinese perimenopausal women; to construct reported symptoms into symptom groupings; and to clarify whether the symptom groups are associated with menopausal status. METHODS a random telephone survey of perimenopausal women aged 44-55 years was conducted in 1996. Eligible subjects were identified through telephone dialing of a random sample of the numbers listed in the residents' telephone directory. Standardized questionnaire, including a 22-item symptom check list, was administered over the telephone. The principal component analysis method followed by varimax rotation was used to examine the relations among the symptoms. RESULTS differences in the prevalence of menstrual problems across the menopausal status were noted with perimenopausal women having the most complaints. Musculoskeletal conditions were the top complaints reported by the respondents, followed by headaches and psychological symptoms. About 10% of the women complained of hot flushes, and less than 5% of cold sweats. Five symptom clusters, namely psychological, musculoskeletal/gastrointestinal, non-specific somatic, respiratory, and vasomotor, have been identified. After adjustment for age, the analysis of variance showed that psychological, non-specific somatic and vasomotor symptoms were significantly associated with menopausal status, while musculoskeletal and respiratory were of borderline statistical significance. CONCLUSIONS compared with pre- and post-menopausal women, perimenopausal women had the highest reports of symptom complaints. Musculoskeletal complaints were the most prevalent complaints, followed by psychological symptoms. While vasomotor symptoms were significantly associated with menopausal status, their prevalence was comparatively lower than that reported in Caucasian populations.
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