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Gianni L, Zambetti M, Clark K, Baker J, Cronin M, Mariani G, Rodriguez J, Carcangiu ML, Valagussa P, Shak S. Gene expression profiles of paraffin-embedded core biopsy tissue predict response to chemotherapy in patients with locally advanced breast cancer. J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.501] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Leichman LP, Lawrence D, Clark K, Nava H, Nava E, Leichman CG, Proulx G, Berdzik J, Greco W, Pendyala L. Updated results of an exploratory gene expression analysis for primary esophageal cancer (PEC) patients (pts) treated with oxaliplatin (OXP), protracted infusion (PI) 5FU and radiation (XRT). J Clin Oncol 2004. [DOI: 10.1200/jco.2004.22.90140.4014] [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
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153
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Opperman J, Clark K, Harris J. Automating the medication system: yesterday's impossibilities are today's realities. Nurs Manag (Harrow) 2004; 32:48-9. [PMID: 15129457 DOI: 10.1097/00006247-200107000-00020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Automating previously manual functions helps reduce the potential for medical errors by introducing objective standards and procedures into the system.
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Baas TJ, Goodwin RN, Christian LL, Johnson RK, Robison OW, Mabry JW, Clark K, Tokach M, Henry S, Berger PJ. Design and standards for genetic evaluation of swine seedstock populations. J Anim Sci 2003; 81:2409-18. [PMID: 14552366 DOI: 10.2527/2003.81102409x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The purpose of this article is to describe a program for evaluation of seedstock populations in the swine industry. Differences among seedstock populations for economically important traits must be identified in order for pork producers to efficiently use available genetic resources. National genetic evaluation programs have the potential to identify the important differences among populations and to increase the rate of genetic improvement in a population. Program results provide performance benchmarks that stimulate testing and selection procedures by seedstock suppliers that further increase the rate of genetic improvement. A Terminal Sire Line Genetic Evaluation Program was designed and conducted in the United States by the National Pork Producers Council (Des Moines, IA) to compare seedstock populations for use in crossbreeding systems. High levels of statistical accuracy for program results were established; the ability to detect differences of 0.25 SD per trait, a power of test of 75%, and a 5% significance level were selected. Pure breeds and breeding company sire lines were nominated for the program. Semen was collected from nominated boars and distributed to cooperating commercial producers during eight 1-wk breeding periods. Pigs were produced in 136 commercial herds and transported to testing facilities at 8 to 23 d of age. Nine of the 11 sire lines originally entered in the program completed the sampling requirements for statistical analysis. High levels of statistical accuracy and a large, representative sample of boars with restrictions on genetic relationships ensured that the program results included unbiased, highly accurate sire line data for growth, carcass, meat quality, and eating quality traits of economic importance. This program has shown commercial producers that they have several choices of sire lines for changing their crossbreeding programs in desired trait areas. Commercial product evaluation must be an ongoing process, and this program serves as a model for future testing and evaluation of diverse genetic seedstock populations.
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Gallagher P, Clark K. The ethics of surgery in the elderly demented patient with bowel obstruction. JOURNAL OF MEDICAL ETHICS 2002; 28:105-108. [PMID: 11934940 PMCID: PMC1733562 DOI: 10.1136/jme.28.2.105] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
OBJECTIVE Little has been written in the medical literature concerning the ethics of treatment of the elderly demented patient with bowel obstruction. It is one example of the issues with which we are becoming increasingly involved. We conducted a survey of our colleagues' opinions to determine current practice. DESIGN A postal questionnaire study (62% response rate). Questions were posed that related to a case scenario of an elderly demented patient presenting with a presumed sigmoid volvulus. SETTING The northern region of England. PARTICIPANTS Thirty seven surgical members of the Association of Coloproctology of Great Britain and Ireland, Northern Chapter. RESULTS Sixty five per cent of respondents felt that surgery would be inappropriate, and 26% that any intervention at all upon the subject in the case scenario would be inappropriate. More would operate, however, at the request of relatives. An advance directive not to treat would be respected by 70% despite a relative's wishes. CONCLUSIONS Overall there was a wide variation in the approach of the surgeons to a demented patient with bowel obstruction. In an era of clinical governance, and an increased awareness of the ethics of consent, this study presents one example of the difficult decisions with which we are increasingly faced. The greater use of advance directives may provide one possible solution.
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Park HK, Burnstein RA, Chakravorty A, Chan A, Chen YC, Choong WS, Clark K, Dukes EC, Durandet C, Felix J, Gidal G, Gu P, Gustafson HR, Ho C, Holmstrom T, Huang M, James C, Jenkins CM, Kaplan DM, Lederman LM, Leros N, Longo MJ, Lopez F, Lu L, Luebke W, Luk KB, Nelson KS, Perroud JP, Rajaram D, Rubin HA, Teng PK, Volk J, White C, White S, Zyla P. Observation of the decay K- --> pi(-)mu(+)mu(-) and measurements of the branching ratios for K+/- --> pi(+/-)mu(+)mu(-). PHYSICAL REVIEW LETTERS 2002; 88:111801. [PMID: 11909394 DOI: 10.1103/physrevlett.88.111801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2001] [Indexed: 05/23/2023]
Abstract
Using data collected with the HyperCP (E871) spectrometer during the 1997 fixed-target run at Fermilab, we report the first observation of the decay K--->pi(-)mu(+)mu(-) and new measurements of the branching ratios for K+/--->pi(+/-)mu(+)mu(-). By combining the branching ratios for the decays K+-->pi(+)mu(+)mu(-) and K--->pi(-)mu(+)mu(-), we measure Gamma(K+/--->pi(+/-)mu(+)mu(-))/Gamma(K+/--->all) = (9.8+/-1.0+/-0.5)x10(-8). The CP asymmetry between the rates of the two decay modes is [Gamma(K+-->pi(+)mu(+)mu(-))-Gamma(K--->pi(-)mu(+)mu(-))]/[Gamma(K+-->pi(+)mu(+)mu(-))+Gamma(K--->pi(-)mu(+)mu(-))] = -0.02+/-0.11+/-0.04.
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Jakicic JM, Clark K, Coleman E, Donnelly JE, Foreyt J, Melanson E, Volek J, Volpe SL. American College of Sports Medicine position stand. Appropriate intervention strategies for weight loss and prevention of weight regain for adults. Med Sci Sports Exerc 2001; 33:2145-56. [PMID: 11740312 DOI: 10.1097/00005768-200112000-00026] [Citation(s) in RCA: 410] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In excess of 55% of adults in the United States are classified as either overweight (body mass index = 25-29.9 kg.m(-2)) or obese (body mass index > or = 30 kg.m(-2)). To address this significant public health problem, the American College of Sports Medicine recommends that the combination of reductions in energy intake and increases in energy expenditure, through structured exercise and other forms of physical activity, be a component of weight loss intervention programs. An energy deficit of 500-1000 kcal.d-1 achieved through reductions in total energy intake is recommended. Moreover, it appears that reducing dietary fat intake to <30% of total energy intake may facilitate weight loss by reducing total energy intake. Although there may be advantages to modifying protein and carbohydrate intake, the optimal doses of these macronutritents for weight loss have not been determined. Significant health benefits can be recognized with participation in a minimum of 150 min (2.5 h) of moderate intensity exercise per week, and overweight and obese adults should progressively increase to this initial exercise goal. However, there may be advantages to progressively increasing exercise to 200-300 min (3.3-5 h) of exercise per week, as recent scientific evidence indicates that this level of exercise facilitates the long-term maintenance of weight loss. The addition of resistance exercise to a weight loss intervention will increase strength and function but may not attenuate the loss of fat-free mass typically observed with reductions in total energy intake and loss of body weight. When medically indicated, pharmacotherapy may be used for weight loss, but pharmacotherapy appears to be most effective when used in combination with modifications of both eating and exercise behaviors. The American College of Sports Medicine recommends that the strategies outlined in this position paper be incorporated into interventions targeting weight loss and the prevention of weight regain for adults.
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Clark K, Fischman J. Out in the cold. Healthcare cost shock means less coverage for some, none for others. U.S. NEWS & WORLD REPORT 2001; 131:52-4, 56, 58-62. [PMID: 11715867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
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159
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Clark K, Bender G, Murray BP, Panfilio K, Cook S, Davis R, Murnen K, Tuan RS, Gilbert SF. Evidence for the neural crest origin of turtle plastron bones. Genesis 2001; 31:111-7. [PMID: 11747201 DOI: 10.1002/gene.10012] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The migrating cranial neural crest cells of birds, fish, and mammals have been shown to form the membranous bones of the cranium and face. These findings have been extrapolated to suggest that all the dermal bones of the vertebrate exoskeleton are derived from the neural crest ectomesenchyme. However, only one group of extant animals, the Chelonians, has an extensive bony exoskeleton in the trunk. We have previously shown that the autapomorphic carapacial and plastron bones of the turtle shell arise from dermal intramembranous ossification. Here, we show that the bones of the plastron stain positively for HNK-1 and PDGFRalpha and are therefore most likely of neural crest origin. This extends the hypothesis of the neural crest origin of the exoskeleton to include the turtle plastron.
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Clark K. How to develop and validate a total organic carbon method for cleaning applications. PDA J Pharm Sci Technol 2001; 55:290-4. [PMID: 11605253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
Good Manufacturing Practices require that the cleaning of drug manufacturing equipment be validated. Common analytical techniques used in the validation process include HPLC, UV/Vis, and Total Organic Carbon (TOC). HPLC and UV/Vis are classified as specific methods that identify and measure appropriate active substances. TOC is classified as a non-specific method and can detect all carbon-containing compounds, including active substances, excipients, and cleaning agents. The disadvantage of specific methods is that a new procedure must be developed for every active drug substance that is manufactured. This development process can be very time consuming and tedious. In contrast, one TOC method can potentially be used for all products. A TOC method is sensitive to the ppb range and is less time consuming than HPLC or UV/Vis. USP TOC methods are standard for Water for Injection and Purified Water, and simple modifications of these methods can be used for cleaning validation. The purpose of this study is to demonstrate how to develop and validate a TOC method for cleaning applications. Performance parameters evaluated in this study include linearity, MDL, LOQ, accuracy, precision, and swab recovery.
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161
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Clark K. Bringing up bold babies. U.S. NEWS & WORLD REPORT 2001; 131:76-7. [PMID: 11521548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
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162
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Jaju RJ, Fidler C, Haas OA, Strickson AJ, Watkins F, Clark K, Cross NC, Cheng JF, Aplan PD, Kearney L, Boultwood J, Wainscoat JS. A novel gene, NSD1, is fused to NUP98 in the t(5;11)(q35;p15.5) in de novo childhood acute myeloid leukemia. Blood 2001; 98:1264-7. [PMID: 11493482 DOI: 10.1182/blood.v98.4.1264] [Citation(s) in RCA: 183] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The recurrent translocation t(5;11)(q35;p15.5) associated with a 5q deletion, del(5q), has been reported in childhood acute myeloid leukemia (AML). We report the cloning of the translocation breakpoints in de novo childhood AML harboring a cryptic t(5;11)(q35;p15.5). Fluorescence in situ hybridization (FISH) analysis demonstrated that the nucleoporin gene (NUP98) at 11p15.5 was disrupted by this translocation. By using 3'--rapid amplification of complementary DNA ends (3'-RACE) polymerase chain reaction, we identified a chimeric messenger RNA that results in the in-frame fusion of NUP98 to a novel gene, NSD1. The NSD1 gene has 2596 amino acid residues and a 85% homology to the murine Nsd1 with the domain structure being conserved. The NSD1 gene was localized to 5q35 by FISH and is widely expressed. The reciprocal transcript, NSD1-NUP98, was also detected by reverse transcriptase--polymerase chain reaction. This is the first report in which the novel gene NSD1 has been implicated in human malignancy. (Blood. 2001;98:1264-1267)
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163
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Schenkman ML, Clark K, Xie T, Kuchibhatla M, Shinberg M, Ray L. Spinal movement and performance of a standing reach task in participants with and without Parkinson disease. Phys Ther 2001; 81:1400-11. [PMID: 11509070 DOI: 10.1093/ptj/81.8.1400] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND AND PURPOSE Evidence suggests that individuals with early and mid-stage Parkinson disease (PD) have diminished range of motion (ROM). Spinal ROM influences the ability to function. In this investigation, the authors examined available spinal ROM, segmental excursions (the ROM used) during reaching, and their relationships in community-dwelling adults with and without PD. SUBJECTS The subjects were 16 volunteers with PD (modified Hoehn and Yahr stages 1.5-3) and 32 participants without PD who were matched for age, body mass index, and sex. METHODS Range of motion of the extremities was measured using a goniometer, and ROM of the spine was measured using the functional axial rotation (FAR) test, a measure of unrestricted cervico-thoracic-lumbar rotation in the seated position. Motion during reaching was determined using 3-dimensional motion analysis. Group differences were determined using multivariable analysis of variance followed by analysis of variance. Contributions to total reaching distance of segmental excursions (eg, thoracic rotation, thoracic lateral flexion) were determined using forward stepwise regression. RESULTS Subjects with PD as compared with subjects without PD had less ROM (FAR of 98.2 degrees versus 110.3 degrees, shoulder flexion of 151.9 degrees versus 160.1 degrees) and less forward reaching (29.5 cm versus 34.0 cm). Lateral trunk flexion and total rotation relative to the ground contributed to reaching, with the regression model explaining 36% of the variance. DISCUSSION AND CONCLUSION These results contribute to the growing body of evidence demonstrating that spinal ROM is impaired early in PD.
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Mattes J, Yang M, Siqueira A, Clark K, MacKenzie J, McKenzie AN, Webb DC, Matthaei KI, Foster PS. IL-13 induces airways hyperreactivity independently of the IL-4R alpha chain in the allergic lung. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:1683-92. [PMID: 11466392 DOI: 10.4049/jimmunol.167.3.1683] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The potent spasmogenic properties of IL-13 have identified this molecule as a potential regulator of airways hyperreactivity (AHR) in asthma. Although IL-13 is thought to primarily signal through the IL-13Ralpha1-IL-4Ralpha complex, the cellular and molecular components employed by this cytokine to induce AHR in the allergic lung have not been identified. By transferring OVA-specific CD4(+) T cells that were wild type (IL-13(+/+) T cells) or deficient in IL-13 (IL-13(-/-) T cells) to nonsensitized mice that were then challenged with OVA aerosol, we show that T cell-derived IL-13 plays a key role in regulating AHR, mucus hypersecretion, eotaxin production, and eosinophilia in the allergic lung. Moreover, IL-13(+/+) T cells induce these features (except mucus production) of allergic disease independently of the IL-4Ralpha chain. By contrast, IL-13(+/+) T cells did not induce disease in STAT6-deficient mice. This shows that IL-13 employs a novel component of the IL-13 receptor signaling system that involves STAT6, independently of the IL-4Ralpha chain, to modulate pathogenesis. We show that this novel pathway for IL-13 signaling is dependent on T cell activation in the lung and is critically linked to downstream effector pathways regulated by eotaxin and STAT6.
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165
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Wright JT, Redline S, Taylor AL, Aylor J, Clark K, O'Malia B, Graham G, Liao GS, Morton S. Relationship between 24-H blood pressure and sleep disordered breathing in a normotensive community sample. Am J Hypertens 2001; 14:743-8. [PMID: 11497188 DOI: 10.1016/s0895-7061(01)01299-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Sleep disordered breathing (SDB) and hypertension are commonly associated. In this study, we assessed how longitudinal measures of SDB predict a 24-h ambulatory blood pressure monitoring (ABPM) profile. Participants (n = 82) were recruited from a community-based urban (26% African American) sample and included family members of patients with laboratory diagnosed SDB (cases) and family members of neighborhood control subjects evaluated at baseline and at 5 years. Nearly all participants were normotensive and were not receiving therapy for SDB. During both examinations, the respiratory distress index (RDI) was assessed with overnight in-home polysomnography. Seated blood pressure (BP) was assessed at a baseline examination (t,) and after a 5-year follow-up period (t5), when 24-h ABPM also was performed. The change in RDI (t5-t1) over 5 years was significantly associated with 24-h mean systolic blood pressure (SBP) (P = .04), 24-h maximum diastolic blood pressure (DBP) (P = .03), sleep mean SBP (P = .05), sleep mean DBP (P < .05), and sleep maximum SBP (P = .02). Regression analysis revealed that average 24-h mean arterial pressure (MAP) and mean 24-h DBP were each best predicted by change in RDI, explaining 5% of the variance in these 24-h BP readings, and by current smoking status. After accounting for these variables, BP was not predicted by any of the other potential confounders (all P > .10). Mean RDI (averaged between t5 and t1) was associated with mean MAP, mean SBP, and maximal SBP measured during sleep. This study documents for the first time the association between changes in sleep apnea activity and BP and in a community-based normotensive sample. Further long-term evaluation of the effects of these findings and the long-term consequences of hypertension are needed.
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Shaw J, Claridge G, Clark K. Schizotypy and the shift from dextrality: a study of handedness in a large non-clinical sample. Schizophr Res 2001; 50:181-9. [PMID: 11439239 DOI: 10.1016/s0920-9964(00)00167-5] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Numerous previous studies have reported associations between schizophrenia/schizotypy and atypical handedness. While there is broad agreement that schizophrenia/schizotypy is associated with a shift away from typical (strong right) handedness, it is not entirely clear what aspect of atypical handedness is implicated: 'ambiguous' handedness (the absence of hand preference for given actions) or 'mixed handedness' (different hand preferences for different actions). The present study used several indices of handedness (derived from the Annett scale) to address these questions in 3000 + (mostly) University student subjects recruited by electronic mail. It was found that positive schizotypy (indexed by a scale of 'unusual experiences') was associated with both aspects of atypical handedness. These findings are discussed in the light of various possible explanations of the association between handedness and schizophrenia/schizotypy.
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167
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Gibbs J, Clark K, Khuri S, Henderson W, Hur K, Daley J. Validating risk-adjusted surgical outcomes: chart review of process of care. Int J Qual Health Care 2001; 13:187-96. [PMID: 11476143 DOI: 10.1093/intqhc/13.3.187] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE The primary purpose of this study was to validate risk-adjusted surgical outcomes as indicators of the quality of surgical care at US Department of Veterans Affairs (VA) hospitals. The secondary purpose was to validate the risk-adjustment models for screening cases for quality review. DESIGN We compared quality of care, determined by structured implicit chart review, for patients from hospitals with higher and lower than expected operative mortality and morbidity (hospital-level tests) and between patients with high and low predicted risk of mortality and morbidity who died or developed complications (patient-level tests). SUBJECTS 739 general, peripheral vascular and orthopedic surgery cases sampled from the 44 VA hospitals participating in the National VA Surgical Risk Study. MAIN OUTCOME MEASURES A global rating of quality of care based on chart review. RESULTS Ratings of overall quality of care did not differ significantly between patients from hospitals with higher and lower than expected mortality and morbidity. On some of the secondary measures, patient care was rated higher for hospitals with lower than expected operative mortality. At the patient level of analysis, those who died or developed complications and had a high predicted risk of mortality or morbidity were rated higher on quality of care than those with a low predicted risk of adverse outcome. CONCLUSIONS The absence of a relationship between most of our measures of process of care and risk-adjusted outcomes may be due to an insensitivity of chart reviews to hospital-level differences in quality of care. Site visits to National VA Surgical Risk Study hospitals with high and low risk-adjusted mortality and morbidity have detected differences on a number of dimensions of quality. The patient-level findings suggest that the risk-adjustment models are useful for screening adverse outcome cases for quality of care review.
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Abstract
In the past few years, a large number of new chemokines (chemotactic cytokines) and chemokine receptors have been discovered. The growth in knowledge about these molecules has been achieved largely through advances in bioinformatics and the expansion of expression sequence tag (EST) databases. It is now clear that chemokines are crucial in controlling both the development and functioning of leukocytes and that their role is not restricted to cell attraction, as originally assumed. In particular, recent findings provide strong support for the idea that chemokines and their receptors are especially important in the control of viral infection and replication. Thus, specific chemokines are now known to enhance the cytotoxic activity of infected cells, thus inhibiting further virus replication. In addition, some chemokines orchestrate the recruitment of activated leukocytes to foci of infection to aid viral clearance. Viruses, in turn, have evolved various defences against chemokines. These range from the production of proteins that inhibit biological activity of the host chemokine to the hijacking of the chemokine system, whereby certain viruses utilize chemokine receptors for their entry. The latter viral defence can itself be blocked by chemokines. Altogether, these findings illustrate the central role of chemokines in many different phases of the immune response, particularly those aspects involving antiviral defence, a variety and versatility that was not fully appreciated even a few years ago.
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Guo K, Searfoss G, Krolikowski D, Pagnoni M, Franks C, Clark K, Yu KT, Jaye M, Ivashchenko Y. Hypoxia induces the expression of the pro-apoptotic gene BNIP3. Cell Death Differ 2001; 8:367-76. [PMID: 11550088 DOI: 10.1038/sj.cdd.4400810] [Citation(s) in RCA: 242] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2000] [Revised: 10/25/2000] [Accepted: 11/08/2000] [Indexed: 11/09/2022] Open
Abstract
It has been shown that oxygen deprivation results in apoptotic cell death, and that hypoxia inducible factor 1 (HIF1) and the tumor suppressor p53 play key roles in this process. However, the molecular mechanism through which hypoxia and HIF1 induce apoptosis is not clear. Here we show that the expression of pro-apoptotic gene BNIP3 is dramatically induced by hypoxia in various cell types, including primary rat neonatal cardiomyocytes. Overexpression of HIF1alpha, but not p53, induces the expression of BNIP3. Overexpression of BNIP3 leads to a rather unusual type of apoptosis, as no cytochrome c leakage from mitochondria was detected and inhibitors of caspases were unable to prevent cell death. Taken together, these data suggest that HIF1-dependent induction of BNIP3 may play a significant role during hypoxia-induced cell death.
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Walker CS, Shetty RP, Clark K, Kazuko SG, Letsou A, Olivera BM, Bandyopadhyay PK. On a potential global role for vitamin K-dependent gamma-carboxylation in animal systems. Evidence for a gamma-glutamyl carboxylase in Drosophila. J Biol Chem 2001; 276:7769-74. [PMID: 11110799 DOI: 10.1074/jbc.m009576200] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The vitamin K-dependent gamma-carboxylation of glutamate to gamma-carboxyglutamate was originally well characterized in the mammalian blood clotting cascade. gamma-Carboxyglutamate has also been found in a number of other mammalian proteins and in neuropeptides from the venoms of marine snails belonging to the genus Conus, suggesting wider prevalence of gamma-carboxylation. We demonstrate that an open reading frame from a Drosophila melanogaster cDNA clone encodes a protein with vitamin K-dependent gamma-carboxylase activity. The open reading frame, 670 amino acids in length, is truncated at the C-terminal end compared with mammalian gamma-carboxylase, which is 758 amino acids. The mammalian gene has 14 introns; in Drosophila there are two much shorter introns but in positions precisely homologous to two of the mammalian introns. In addition, a deletion of 6 nucleotides is observed when cDNA and genomic sequences are compared. In situ hybridization to fixed embryos indicated ubiquitous presence of carboxylase mRNA throughout embryogenesis. Northern blot analysis revealed increased mRNA levels in 12-24-h embryos. The continued presence of carboxylase mRNA suggests that it plays an important role during embryogenesis. Although the model substrate FLEEL is carboxylated by the enzyme, a substrate containing the propeptide of a Conus carboxylase substrate, conantokin G, is poorly carboxylated. Its occurrence in vertebrates, molluscan systems (i.e. Conus), and Drosophila and the apparently strong homology between the three systems suggest that this is a highly conserved and widely distributed post-translational modification in biological systems.
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Clark K, Shute N. The adoption maze. U.S. NEWS & WORLD REPORT 2001; 130:60-6, 69. [PMID: 11252363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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172
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Isaacs RJ, Hunter W, Clark K. Tamoxifen as systemic treatment of advanced breast cancer during pregnancy--case report and literature review. Gynecol Oncol 2001; 80:405-8. [PMID: 11263941 DOI: 10.1006/gyno.2000.6080] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
BACKGROUND When patients with metastatic breast cancer become pregnant, management is complicated by the potential harms of drug treatment to the fetus and by the potential effects of the pregnancy on the cancer. Chemotherapy is considered optimal systemic anti-cancer therapy from the second trimester, while tamoxifen has been considered inappropriate due to concerns over possible teratogenesis and lack of efficacy. CASE We report a patient who became pregnant concurrent with the identification of metastatic breast cancer and who elected to continue her pregnancy with tamoxifen as sole systemic anti-cancer therapy. The pregnancy was difficult, but a normal child was delivered and the mother responded to subsequent hormone manipulation. The putative teratogenic effects of tamoxifen and the mechanisms underlying tamoxifen resistance in this setting are discussed. CONCLUSIONS The use of tamoxifen in pregnancy is complex, but is not necessarily associated with fetal harm and may be considered a therapeutic option in selected cases.
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Hamel L, Kenney M, Jayyosi Z, Ardati A, Clark K, Spada A, Zilberstein A, Perrone M, Kaplow J, Merkel L, Rojas C. Induction of heat shock protein 70 by herbimycin A and cyclopentenone prostaglandins in smooth muscle cells. Cell Stress Chaperones 2001. [PMID: 11147963 DOI: 10.1379/1466-1268(2000)005<0121:iohspb>2.0.co;2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
This study characterizes Hsp70 induction in human smooth muscle cells (SMC) by herbimycin A and cyclopentenone prostaglandins. The magnitude of Hsp70 induction by cyclopentenone prostaglandins was 8- to 10-fold higher than induction by herbimycin A. Hsp70 induction by delta12PGJ2 was first observed at 10 microM, rose to 4000-5000 ng/mL within one log unit and a maximum response was not observed; concentrations of delta12PGJ2 higher than 30 microM were toxic to the cells. A maximum response with herbimycin A (500 ng/mL) was reached at 0.05 microM and maintained to 1 microM without toxicity. Both, delta12PGJ2 and herbimycin A, were inhibited by dithiothreitol (DTT, 100 microM) at lower concentrations and became less sensitive to inhibition at higher concentrations. Hsp70 induction after incubation of SMC with delta12PGJ2 followed by addition of herbimycin A was significantly higher than Hsp70 induction after incubation with herbimycin A followed by addition of delta12PGJ2. When cells were incubated with [3H]-PGJ2, followed by protein denaturation, substantial radioactivity remained protein-bound suggesting that the prostaglandin must be covalently bound. Covalent binding was largely insensitive to DTT. Maximal Hsp70 induction was observed after 5 minutes of exposure of the cells to herbimycin A followed by a 20 hour recovery period in agent-free medium. Cells required 3-4 hours of exposure to delta12PGJ2 followed by a 20 hour recovery period in order to see high Hsp70 induction. Binding of the heat shock factor (HSF) to the heat shock element (HSE) in the presence of herbimycin A or delta12PGJ2, and the effects of DTT, mirrored the results of Hsp70 induction. The results suggest that probable differences between the 2 agents are at the level of the signal transduction prior to HSF activation.
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Daniels RJ, Peden JF, Lloyd C, Horsley SW, Clark K, Tufarelli C, Kearney L, Buckle VJ, Doggett NA, Flint J, Higgs DR. Sequence, structure and pathology of the fully annotated terminal 2 Mb of the short arm of human chromosome 16. Hum Mol Genet 2001; 10:339-52. [PMID: 11157797 DOI: 10.1093/hmg/10.4.339] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
We have sequenced 1949 kb from the terminal Giemsa light band of human chromosome 16p, enabling us to fully annotate the region extending from the telomeric repeats to the previously published tuberous sclerosis disease 2 (TSC2) and polycystic kidney disease 1 (PKD1) genes. This region can be subdivided into two GC-rich, Alu-rich domains and one GC-rich, Alu-poor domain. The entire region is extremely gene rich, containing 100 confirmed genes and 20 predicted genes. Many of the genes encode widely expressed proteins orchestrating basic cellular processes (e.g. DNA recombination, repair, transcription, RNA processing, signal transduction, intracellular signalling and mRNA translation). Others, such as the alpha globin genes (HBA1 and HBA2), PDIP and BAIAP3, are specialized tissue-restricted genes. Some of the genes have been previously implicated in the pathophysiology of important human genetic diseases (e.g. asthma, cataracts and the ATR-16 syndrome). Others are known disease genes for alpha thalassaemia, adult polycystic kidney disease and tuberous sclerosis. There is also linkage evidence for bipolar affective disorder, epilepsy and autism in this region. Sixty-three chromosomal deletions reported here and elsewhere allow us to interpret the results of removing progressively larger numbers of genes from this well defined human telomeric region.
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175
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Flint J, Tufarelli C, Peden J, Clark K, Daniels RJ, Hardison R, Miller W, Philipsen S, Tan-Un KC, McMorrow T, Frampton J, Alter BP, Frischauf AM, Higgs DR. Comparative genome analysis delimits a chromosomal domain and identifies key regulatory elements in the alpha globin cluster. Hum Mol Genet 2001; 10:371-82. [PMID: 11157800 DOI: 10.1093/hmg/10.4.371] [Citation(s) in RCA: 132] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have cloned, sequenced and annotated segments of DNA spanning the mouse, chicken and pufferfish alpha globin gene clusters and compared them with the corresponding region in man. This has defined a small segment ( approximately 135-155 kb) of synteny and conserved gene order, which may contain all of the elements required to fully regulate alpha globin gene expression from its natural chromosomal environment. Comparing human and mouse sequences using previously described methods failed to identify the known regulatory elements. However, refining these methods by ranking identity scores of non-coding sequences, we found conserved sequences including the previously characterized alpha globin major regulatory element. In chicken and pufferfish, regions that may correspond to this element were found by analysing the distribution of transcription factor binding sites. Regions identified in this way act as strong enhancer elements in expression assays. In addition to delimiting the alpha globin chromosomal domain, this study has enabled us to develop a more sensitive and accurate routine for identifying regulatory elements in the human genome.
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