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Halldorsson AO, Vigneswaran WT, Podbielski FJ, Evans DM. Electrophysiological and clinical comparison of two temporary pacing leads following cardiac surgery. Pacing Clin Electrophysiol 1999; 22:1221-5. [PMID: 10461299 DOI: 10.1111/j.1540-8159.1999.tb00603.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Temporary pacing leads are invaluable in diagnosis and treatment of arrhythmia after cardiac surgery. The ideal lead possesses reliable pacing and sensing capabilities throughout the postoperative period. Ease of handling and a low complication rate are essential. This study compares a new lead (Medtronic model #6492) to a temporary pacemaker lead established in clinical use (Medtronic model #6500). One lead of each type was placed in the right atrium and ventricle in 33 patients undergoing elective coronary revascularization. Pacing function was measured on the first and fourth postoperative days. Lead complications were documented. On day 1, there was no statistical difference between lead types in terms of pacing (voltage threshold, current threshold), impedance, or sensing (P wave amplitude, R wave amplitude). On day 4, both leads showed an increase in pacing threshold and a decrease in sensing ability. The only statistical difference between lead types was in atrial sensing on day 4, as measured by the P wave amplitudes (1.95 +/- 0.18 V for model 6492 vs 1.40 +/- 0.14 V for model 6500, P < 0.05). Two leads of each model failed to pace in the ventricular position and one lead in each model in the atrial position. There were no complications attributable to either pacemaker lead. We found that both lead types were reliable and functioned well. The Medtronic Model #6492 lead demonstrated better long-term sensing, although in this study the difference was not clinically significant.
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Evans DM. Stroke education: the development of a documentation system and resource guide. AXONE (DARTMOUTH, N.S.) 1998; 20:19-22. [PMID: 9849139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Mink van der Molen AB, Hall MA, Evans DM. Ulnar lengthening in juvenile chronic arthritis. JOURNAL OF HAND SURGERY (EDINBURGH, SCOTLAND) 1998; 23:438-41. [PMID: 9726540 DOI: 10.1016/s0266-7681(98)80118-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Ten wrists in eight children with severe destructive changes in the wrist due to juvenile chronic arthritis underwent distraction lengthening of the ulna between 1983 and 1996 in an attempt to restore wrist alignment, which had not been preserved by previous splinting. Eight wrists in six patients (four female and two male) were evaluated. The average age at the time of operation was 13.8 years (range, 12-15.5). The average follow-up period was 70 months (range, 12-152). The average ulna minus deformity was between 8 and 9 mm. It was found that ulnar lengthening can be done safely and the procedure seems to stabilize the carpus, is likely to improve appearance, may improve function and in the majority of cases does eliminate the use of an external splint. Results seem to be stable for at least 3 to 5 years.
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Evans DM, Sloan-Stakleff K, Arvan M, Guyton DP. Time and dose dependency of the suppression of pulmonary metastases of rat mammary cancer by amiloride. Clin Exp Metastasis 1998; 16:353-7. [PMID: 9626814 DOI: 10.1023/a:1006517614491] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Amiloride is an inhibitor of urokinase plasminogen activator (uPA), an essential component of the plasminogen/plasmin enzyme system. Inhibition of uPA prevents the conversion of plasminogen to tumor cell surface bound plasmin which is required for initiation of the metastatic process. MATB rat mammary cancer cells were introduced into the jugular venous system of 80 Fisher 344 female rats. Amiloride at high and low dosages was administered in the drinking water at the time of, prior to or several days following the tumor cell inoculation and continued daily for 10 days post inoculation. Control rats were maintained on water alone. The middle lobe of the right lung was examined microscopically for numbers of metastases. Suppression of metastases was significant at high amiloride dosages in all groups, and at low dosage when administered prior to inoculation. We conclude that amiloride suppresses induced metastases of rat mammary cancer, the effect being dose- and time-dependent.
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Semple G, Ashworth DM, Batt AR, Baxter AJ, Benzies DW, Elliot LH, Evans DM, Franklin RJ, Hudson P, Jenkins PD, Pitt GR, Rooker DP, Yamamoto S, Isomura Y. Peptidomimetic aminomethylene ketone inhibitors of interleukin-1 beta-converting enzyme (ICE). Bioorg Med Chem Lett 1998; 8:959-64. [PMID: 9871520 DOI: 10.1016/s0960-894x(98)00136-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Pyridone-based peptidomimetic inhibitors of recombinant human Interleukin-1 beta-converting enzyme (ICE, caspase-1) with an aminomethylene ketone activating group in the P1' position are described. Several analogues with sub-nanomolar Ki's versus ICE and improved aqueous solubility are reported.
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Wallace HM, Evans DM. Measurement of spermidine/spermine N1-acetyltransferase activity. Methods Mol Biol 1998; 79:59-68. [PMID: 9463818 DOI: 10.1385/0-89603-448-8:59] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Wilson Y, Fogelman I, Evans DM. Detection of an elusive osteoid osteoma using a registration bone scan. JOURNAL OF HAND SURGERY (EDINBURGH, SCOTLAND) 1997; 22:801-4. [PMID: 9457593 DOI: 10.1016/s0266-7681(97)80453-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
A case of osteoid osteoma in a young man is presented which evaded diagnosis for 9 years, and was eventually localized to the palmar aspect of the third carpometacarpal joint using the technique of registration bone scan to provide accurate localization. The lesion was removed with complete relief of pain.
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Brown RA, Evans DM, Miller IW, Burgess ES, Mueller TI. Cognitive-behavioral treatment for depression in alcoholism. J Consult Clin Psychol 1997. [PMID: 9337490 DOI: 10.1037//0022-006x.65.5.715] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Alcoholics with depressive symptoms score > or = 10 on the Beck Depression Inventory (A.T. Beck, C. H. Ward, M. Mendelson, J. Mock, & J. Erbaugh, 1961) received 8 individual sessions of cognitive-behavioral treatment for depression (CBT-D, n = 19) or a relaxation training control (RTC; n = 16) plus standard alcohol treatment. CBT-D patients had greater reductions in somatic depressive symptoms and depressed and anxious mood than RTC patients during treatment. Patients receiving CBT-D had a greater percentage of days abstinent but not greater overall abstinence or fewer drinks per day during the first 3-month follow-up. However, between the 3- and 6-month follow-ups, CBT-D patients had significantly better alcohol use outcomes on total abstinence (47% vs. 13%), percent days abstinent (90.5% vs. 68.3%), and drinks per day (0.46 vs. 5.71). Theoretical and clinical implications of using CBT-D in alcohol treatment are discussed.
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Brown RA, Evans DM, Miller IW, Burgess ES, Mueller TI. Cognitive-behavioral treatment for depression in alcoholism. J Consult Clin Psychol 1997; 65:715-26. [PMID: 9337490 PMCID: PMC1885208 DOI: 10.1037/0022-006x.65.5.715] [Citation(s) in RCA: 140] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Alcoholics with depressive symptoms score > or = 10 on the Beck Depression Inventory (A.T. Beck, C. H. Ward, M. Mendelson, J. Mock, & J. Erbaugh, 1961) received 8 individual sessions of cognitive-behavioral treatment for depression (CBT-D, n = 19) or a relaxation training control (RTC; n = 16) plus standard alcohol treatment. CBT-D patients had greater reductions in somatic depressive symptoms and depressed and anxious mood than RTC patients during treatment. Patients receiving CBT-D had a greater percentage of days abstinent but not greater overall abstinence or fewer drinks per day during the first 3-month follow-up. However, between the 3- and 6-month follow-ups, CBT-D patients had significantly better alcohol use outcomes on total abstinence (47% vs. 13%), percent days abstinent (90.5% vs. 68.3%), and drinks per day (0.46 vs. 5.71). Theoretical and clinical implications of using CBT-D in alcohol treatment are discussed.
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Featherstone RL, Parry JE, Evans DM, Jones DM, Olsson H, Szelke M, Church MK. Mechanism of irritant-induced cough: studies with a kinin antagonist and a kallikrein inhibitor. Lung 1996; 174:269-75. [PMID: 8791263 DOI: 10.1007/bf00173141] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
It has been suggested that bradykinin may play a role in stimulating cough in at least one pathological condition in humans. We have employed an animal model to investigate the possible role of this peptide in irritant-induced cough. The kinin antagonist Hoe 140 and codeine both produced dose-related inhibition of cough responses to inhalation of citric acid or bradykinin aerosols by conscious guinea pigs. The selective tissue kallikrein inhibitor CH694 inhibited cough caused by citric acid but not by bradykinin. Indomethacin pretreatment attenuated the responses to both stimuli as did phosphoramidon. It is concluded that cough produced by citric acid inhalation may be mediated, at least in part, by generation of kinins; secondary to this, a release of prostanoids also appears to participate in the response.
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Evans DM, Jones DM, Pitt GR, Sueiras-Diaz J, Horton J, Ashworth D, Olsson H, Szelke M. Selective inhibitors of plasma kallikrein. IMMUNOPHARMACOLOGY 1996; 32:115-6. [PMID: 8796284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Based on a tetrapeptide fragment [Pro387-Ser390] of HK we have developed a series of potent low molecular weight (5-600 Da) inhibitors of PK which are stable to the enzyme. These inhibitors show good selectivity for PK versus tissue kallikrein, thrombin and plasmin. Such inhibitors will help define the role of PK and kinins in human physiology and pathophysiology. They may also find clinical use in the treatment of diseases where kinins are important mediators.
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Evans DM, Jones DM, Pitt GR, Ashworth D, De Clerck F, Verheyen F, Szelke M. Synthetic inhibitors of human tissue kallikrein. IMMUNOPHARMACOLOGY 1996; 32:117-8. [PMID: 8796285 DOI: 10.1016/0162-3109(95)00069-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We have developed a series of novel, potent low molecular weight (4-600 Da) inhibitors of TK which were stable to cleavage by the enzyme and showed a high degree of selectivity for TK over several other serine proteases. Compound 7 (CH-2856) was found to reduce eosinophilia in a model of allergic inflammation. The effects observed in vivo provide further evidence for the involvement of TK and kinins in the pathophysiology of allergic diseases such as asthma.
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Evans DM, Williams KP, McGuinness B, Tarr G, Regnier F, Afeyan N, Jindal S. Affinity-based screening of combinatorial libraries using automated, serial-column chromatography. Nat Biotechnol 1996; 14:504-7. [PMID: 9630929 DOI: 10.1038/nbt0496-504] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We have developed an automated serial chromatographic technique for screening a library of compounds based upon their relative affinity for a target molecule. A "target" column containing the immobilized target molecule is set in tandem with a reversed-phase column. A combinatorial peptide library is injected onto the target column. The target-bound peptides are eluted from the first column and transferred automatically to the reversed-phase column. The target-specific peptide peaks from the reversed-phase column are identified and sequenced. Using a monoclonal antibody (3E-7) against beta-endorphin as a target, we selected a single peptide with sequence YGGFL from approximately 5800 peptides present in a combinatorial library. We demonstrated the applicability of the technology towards selection of peptides with predetermined affinity for bacterial lipopolysaccharide (LPS, endotoxin). We expect that this technology will have broad applications for high throughout screening of chemical libraries or natural product extracts.
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Abstract
Nitric oxide (NO), a mediator of cardiovascular homeostasis, neurotransmission, and immune function, has recently been found to have important effects in bone. Both constitutive and inducible forms of NO synthase are expressed by bone-derived cells, and cytokines such as interleukin-1 (IL-1), tumor necrosis factor (TNF), and interferon gamma (IFN-gamma), are potent stimulators of NO production. When combined with other cytokines, IFN-gamma markedly induces NO production, which suppresses osteoclast formation and activity of mature osteoclasts. This "superinduction" of NO is largely responsible for the selective inhibitory effect of IFN-gamma on cytokine-induced bone resorption. High concentrations of NO are also inhibitory for cells of the osteoblast lineage, and NO production appears to be partly responsible for the inhibitory effects of cytokines on osteoblast proliferation. At lower concentrations, however, NO has different effects. Moderate induction of NO potentiates bone resorption, and the constitutive production of NO at low concentrations promotes the proliferation of osteoblast-like cells and modulates osteoblast function. NO therefore appears to be an important regulatory molecule in bone with effects on cells of the osteoblast and osteoclast lineage and represents one of the molecules produced by osteoblasts which directly regulate osteoclastic activity. Stimulation of NO production in bone by proinflammatory cytokines raises the possibility that NO may be involved as a mediator of bone disease in conditions associated with cytokine activation, such as rheumatoid arthritis, tumor associated osteolysis, and postmenopausal osteoporosis.
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65
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Evans DM, Gateley DR, Telfer JR. Rotation-angulation osteotomy in the hand. JOURNAL OF HAND SURGERY (EDINBURGH, SCOTLAND) 1996; 21:43-6. [PMID: 8676028 DOI: 10.1016/s0266-7681(96)80010-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The use of a single osteotomy combining both rotation and angulation is described, with a means of achieving the correct angle and direction of the osteotomy. Patients who have been treated by this method are presented.
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66
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Evans DM. Facial reconstruction after a burn injury using two circumferential radial forearm flaps, and a dorsalis pedis flap for the nose. BRITISH JOURNAL OF PLASTIC SURGERY 1995; 48:471-6. [PMID: 7551525 DOI: 10.1016/0007-1226(95)90122-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A 21-year-old man is reported in whom flap tissue was required to reconstruct the face and nose following burns. The whole of both forearms were used as radial forearm flaps for both cheeks, both lower eyelids, the right upper eyelid, upper and lower lips and chin. A Tagliacozzi arm flap and a dorsalis pedis flap were used for the nose. The ears were resurfaced using grafted skin along the line of the superficial temporal arteries. No thinning of the flaps was required and some facial muscle attachments to the forearm deep fascia led to more recovery of facial movement than might be expected with a flap reconstruction.
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67
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Evans DM, Lin PL. Suppression of pulmonary metastases of rat mammary cancer by recombinant urokinase plasminogen activator inhibitor. Am Surg 1995; 61:692-6; discussion 696-7. [PMID: 7618808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A pivotal point in the process of invasion and metastasis of cancer cells rests on the capability of those cells to present a proteolytic interface to the surrounding tissue matrix as well as to the lymphovascular channels supplying the tumor. The MATB rat mammary cancer cells used in this study, along with a number of cancers of epithelial cell origin, provide that proteolytic interface by cell surface-bound plasmin. Inhibition of tumor cell surface plasmin formation in this study was achieved through the addition of the urokinase plasminogen activator inhibitor (PAI-2) to the infusion of rat mammary cancer cells introduced into the pulmonary arterial circulation of female Fisher 344 rats. The results show a significant decrease in the numbers of pulmonary metastases in those rats receiving the inhibitor. This effect was demonstrable for cells delivered as a bolus as well as for those delivered slowly over a 7-day period via an osmotic pump. Delivery of the inhibitor was by osmotic pump in each instance. The evidence suggests a basis for an additional approach to control the spread of selected cancers.
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68
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Evans DM, Williams KP, Parsons G, Jindal S. A tandem-column chromatographic method for studying the interaction between ligands and their targets: lipopolysaccharide as a model. Anal Biochem 1995; 229:42-7. [PMID: 8533893 DOI: 10.1006/abio.1995.1376] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The identification of a lead ligand from a library of compounds for a specific target requires both a selection process and a method to assess relative affinities. Using a tandem-column chromatographic technique, we have developed a novel and rapid method for determination of relative affinities for ligands binding to a specific target molecule. We demonstrate, using known ligands for the lipid A region of lipopolysaccharide, that the relative affinities of these ligands can be determined and may be used to characterize the competitive interaction between ligands for the same target. The method can be adapted toward screening of soluble libraries of peptides and small molecules and those ligands exhibiting a desired affinity can be rapidly selected for further characterization/development.
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69
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Abstract
A review of the world literature regarding carcinoma of ectopic breast tissue along with the addition of one case is reported. A total of 90 cases of carcinoma of ectopic breast tissue were found, 64 of which occurred in the axilla. The combined survival beyond the 4-year post-treatment period was 9.4%. No survival advantage was found for radical or modified radical mastectomy over that of local excision combined with axillary dissection or radiation. The addition of radiation therapy to either type of mastectomy provided no additional benefit. The correct preoperative diagnosis was rarely made. Outcome was reported in 42 cases; 28 survived longer than 1 year, with 12 recurrences at the time of reporting, and 6 were alive with no evidence of disease at 4 years or longer. Improved prognosis requires diagnostic suspicion and early biopsy of unidentified lesions of the axilla or embryonic milk line.
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70
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Evans DM, Gateley DR, Lewis JS. The use of a bilobed flap in the correction of radial club hand. JOURNAL OF HAND SURGERY (EDINBURGH, SCOTLAND) 1995; 20:333-7. [PMID: 7561408 DOI: 10.1016/s0266-7681(05)80089-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A new incision is described for the correction of radial club hand. By the use of a bilobed flap, redundant skin is transferred from the ulnar side of the wrist to the radial side, where there is tension as the wrist becomes straight. The flap has been shown to be safe and effective in six consecutive cases, and access to the wrist and surrounding soft tissue structures is excellent.
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71
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Evans DM, Dunn NJ. Alcohol expectancies, coping responses and self-efficacy judgments: a replication and extension of Copper et al.'s 1988 study in a college sample. JOURNAL OF STUDIES ON ALCOHOL 1995; 56:186-93. [PMID: 7760565 DOI: 10.15288/jsa.1995.56.186] [Citation(s) in RCA: 73] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVE Social learning theory models of alcohol use have assumed an increasingly influential role in recent years. Despite their growing popularity, research on social learning theory models has focused almost exclusively on establishing the independent links among particular aspects of theory and indices of alcohol use and abuse. In response to the need for research that incorporates multiple aspects of theory into a testable framework, this article endeavored to replicate and extend the Copper et al. study in a college sample (Cooper, Russell and George, J. Abnorm. Psychol. Vol. 97, pp. 218-230, 1988). METHOD Subjects were 157 college student volunteers from a large midwestern university. Standard hierarchical multiple regression analyses were used to examine both the simultaneous and incremental contributions of self-efficacy judgments, alcohol expectancies and coping responses to dependent measures of alcohol use and alcohol-related problem behaviors. RESULTS Collectively, 22% of the variance in subjects' self-reported use of alcohol and greater than 50% of the variance in subjects' endorsement of alcohol-related problems was explained. Despite considerable overlap among the constructs measured, analyses also demonstrated that each variable accounted for significant and unique variance in the prediction of the criteria. CONCLUSIONS These results provide considerable support for the application of social learning theory principles to the drinking practices of collegiate youth. In particular, the salience of social learning theory constructs as relevant risk factors was highlighted, as lower self-efficacy judgments, positive alcohol expectancies and reliance avoidant, emotion-focused coping strategies were significantly associated with increased alcohol consumption levels and greater endorsement of alcohol-related problem behaviors.
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72
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Evans DM, Lewis JS. Tumoral calcinosis associated with congenital malformations of the hand. JOURNAL OF HAND SURGERY (EDINBURGH, SCOTLAND) 1994; 19:647-52. [PMID: 7822930 DOI: 10.1016/0266-7681(94)90136-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Two cases of tumoral calcinosis are reported in children with congenital hand malformations. After excision of large calcific masses, reconstruction was performed using a free phalangeal graft in one case and a free toe transfer in the other.
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73
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Pinto JC, Potié F, Rice KC, Boring D, Johnson MR, Evans DM, Wilken GH, Cantrell CH, Howlett AC. Cannabinoid receptor binding and agonist activity of amides and esters of arachidonic acid. Mol Pharmacol 1994; 46:516-22. [PMID: 7935333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
The cannabinoid receptor in brain (CB1) specifically binds delta 9-tetrahydrocannabinol, the predominant central nervous system-active component of marijuana. An eicosanoid found in brain, N-(2-hydroxyethyl)arachidonylamide (anandamide), binds to CB1 with similar affinity. This report considers structure-activity requirements for a series of novel amides and rigid hairpin conformations typified by N-(2-hydroxyethyl)prostaglandin amides, assayed with phenylmethylsulfonyl fluoride inactivation of esterases/amidases. Arachidonyl esters were 30-fold less potent than N-(2-hydroxyethyl)arachidonylamide, showing a rank order of potency of methyl = ethyl > propyl = isopropyl. Within the N-(hydroxyalkyl)arachidonylamide series, a one-carbon increase in chain length increased the potency 2-fold, but continued extension decreased affinity. Substituting the amide for the N-(2-hydroxyethyl)amide function produced a 4-fold loss of affinity. The N-(propyl)-, N-(butyl)-, and N-(benzyl)arachidonylamide derivatives exhibited a 3-fold increase, no change, and a 5-fold decrease, respectively, in affinity, compared with N-(2-hydroxyethyl)arachidonylamide. Both the methoxy ether and the formamide derivatives suffered > 20-fold loss of potency, compared with N-(2-hydroxyethyl)arachidonylamide. N-(2-Aminoethyl)arachidonylamide interacted poorly with CB1. At 100 microM, N-(2-hydroxyethyl)amide analogs of prostaglandin E2, A2, B2, and B1 failed to alter [3H]CP55940 binding to CB1. N-(2-Hydroxyethyl)arachidonylamide inhibited adenylate cyclase with lesser potency but with similar efficacy, compared with desacetyllevonantradol. Extending the length of the hydroxyalkyl moiety by one carbon increased the apparent potency by 1 order of magnitude. The N-(propyl) derivative exhibited a 5-fold greater potency than did the N-(2-hydroxyethyl) analog. It appears that the bulk and length of the moiety appended to arachidonic acid are more important determinants of affinity for CB1 than is hydrogen-bonding capability.
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Evans DM, Chevretton EB, Cole RP, Pereira JA, Morrison GA. Through-flow revascularization of the tongue using a radial forearm free flap. BRITISH JOURNAL OF PLASTIC SURGERY 1994; 47:419-21. [PMID: 7952808 DOI: 10.1016/0007-1226(94)90070-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Surgery for invasive squamous cell carcinoma involving the tongue base usually necessitates a total glossectomy because complete tumour resection requires sacrifice of both lingual arteries leaving a non-viable anterior tongue. A case is presented in which both lingual arteries were sacrificed to achieve complete tumour excision and the remaining anterior two-thirds of the tongue were successfully revascularized by through-flow from a radial forearm free flap which was used for pharyngeal reconstruction. This technique offers hope of preservation of the tongue when radical surgery would otherwise lead to its removal.
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75
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Sueiras-Diaz J, Jones DM, Ashworth D, Horton J, Evans DM, Szelke M. Cleavage of human kininogen fragments at Met-Lys by human tissue kallikrein. Braz J Med Biol Res 1994; 27:1935-42. [PMID: 7749384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
1. Tissue kallikrein (TK) cleaves low molecular weight kininogen (LK) at two sites to release kallidin: site I (between Arg389 and Ser390) is a typical cleavage point for a trypsin-like enzyme whereas site II (between Met379 and Lys380) is unusual and unique to TK. In order to learn more about the structural requirements and mechanism of cleavage at site II, we studied the hydrolysis by TK of several synthetic LK fragments varying in length between 4 and 22 residues and containing either site II only or both sites I and II. 2. Blocking site I cleavage in LK fragments by substituting DArg for LArg at position 389 or omitting site I from the sequence still allowed cleavage to proceed at site II. Replacement or deletion of selected amino acid residues in these fragments demonstrated that the presence of Arg381 was essential for site II cleavage to occur whereas Pro383, Phe385 and Ser386 could be replaced with Ala without affecting binding or cleavage by TK. Ki values towards TK were determined for all LK fragments in order to compare their binding affinities to the enzyme. Short peptides containing site II only exhibited high Ki values (> or = 100 microM) whereas longer fragments containing both sites I and II had Ki values of 2-7 microM. 3. In order to bring sites I and II into close proximity spatially and thus facilitating efficient cleavage in the enzyme-substrate complex, we prepared several cyclic analogs of the longer LK fragments.(ABSTRACT TRUNCATED AT 250 WORDS)
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