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Evans M, Kessler D, Lewis G, Peters TJ, Sharp D. Assessing mental health in primary care research using standardized scales: can it be carried out over the telephone? Psychol Med 2004; 34:157-162. [PMID: 14971636 DOI: 10.1017/s0033291703008055] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND Telephone interviewing has economic and logistical advantages but has not been widely used in the UK. Most studies comparing face-to-face and telephone psychiatric assessment have been carried out in the US, often restricted to a population with known psychiatric disorder and involving comparisons between two separate sample groups rather than repeat interviews with the same group. The aim of the present study was to compare face-to-face and telephone administration of the 12-item General Health Questionnaire and the Revised Clinical Interview Schedule in a UK general practice sample. METHOD Ninety-eight consecutive attenders at two general practices were assessed twice within 48 h. The order of face-to-face and telephone interviews was alternated. RESULTS There was no evidence that the mode of administration led to a bias in scores on the CIS-R. For the GHQ, those aged over 60 tended to score higher on the telephone. There was good agreement between face-to-face and telephone scores for both GHQ and CIS-R and good agreement for case definition. Participants had a strong preference for face-to-face interviews. CONCLUSIONS Telephone assessment of mental health using the GHQ and CIS-R is a reasonable method to be used in primary care research in the UK with the limitation that telephone responses from older people might be different from face-to-face assessments for the GHQ. However, telephone interviewing appeared less acceptable and should probably be used in the context of established or ongoing personal contact between researcher and subject.
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Abstract
PURPOSE To evaluate the effect of intrastromal corneal ring segments (Intacs, Keravision) placement on the tear film quality as a measure of dry eye status. METHODS Seventeen eyes of ten patients underwent Intacs placement for the correction of myopia with spherical equivalent refractions ranging from -1.75 to -3.25 D (mean, -2.43 +/- 0.56 D). Dry eye grade values were measured preoperatively and at 1 day, 1 week, and 1 month postoperatively using the Kowa-DR-1 interferometer. RESULTS Preoperatively, the 17 eyes had a mean dry eye grade of 2.18 +/- 0.39 (range, 2 to 3). One day postoperatively, the 14 eyes measured had a mean dry eye grade of 2.64 +/- 0.63 (range, 2 to 4; P = .03). At 1 week the 17 eyes had a mean dry eye grade of 2.41 +/- 0.71 (range, 2 to 4; P = .25) and at 1 month, 2.18 +/- 0.39 (range, 2 to 3; P = .75). CONCLUSIONS There was transient dry eye following Intacs placement, but the tear film quality was restored within 1 week of surgery.
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Kessler D, Dethlefsen S, Haase I, Plomann M, Hirche F, Krieg T, Eckes B. Fibroblasts in mechanically stressed collagen lattices assume a "synthetic" phenotype. J Biol Chem 2001; 276:36575-85. [PMID: 11468280 DOI: 10.1074/jbc.m101602200] [Citation(s) in RCA: 259] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Fibroblasts are subjected to changes of the mechanical force balance during physiological as well as pathological situations, such as wound healing, development of hypertrophic scars, and fibrogenesis. However, the molecular response and the changes in fibroblast gene expression upon mechanical stimulation remain poorly understood. As an in vitro model, human dermal fibroblasts were cultured within a three-dimensional network of fibrillar collagen either under high (stressed) or low tension (relaxed). cDNA microarray technology in combination with Northern blot analysis led to identification of mechano-responsive genes coding for extracellular matrix proteins, fibrogenic growth factors, protease inhibitors, components of focal adhesions, and the cytoskeleton. Application of biaxial strain to fibroblasts cultured on flexible silicone membranes revealed that the type of strain as well as the properties of the substrate induced different patterns of gene regulation. The transcriptional profile of mechanically induced genes in collagen lattices suggests that mechanical stimuli lead to a "synthetic" fibroblast phenotype characterized by induction of connective tissue synthesis while simultaneously inhibiting matrix degradation.
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Abstract
Arrhythmogenic right ventricular dysplasia (ARVD/C) is one cause of death in young adults in the United States, representing approximately 17% of all ARVD/C cases reported. This study presents 2 cases of ARVD/C diagnosed at a central Texas hospital and reviews the literature regarding this disease. The diagnosis, histology, presentation, prognosis, and therapy are addressed because the rare nature of this disease within the United States makes diagnosis and treatment difficult and creates problems of adaptation for the patient. Clinicians must become more familiar with this potentially fatal cardiac disorder that can create vulnerability within a young adult population.
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de Oliveira CF, Diaz RS, Machado DM, Sullivan MT, Finlayson T, Gwinn M, Lackritz EM, Williams AE, Kessler D, Operskalski EA, Mosley JW, Busch MP. Surveillance of HIV-1 genetic subtypesand diversity in the US blood supply. Transfusion 2000; 40:1399-406. [PMID: 11099672 DOI: 10.1046/j.1537-2995.2000.40111399.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Recent reports of variant (non-subtype B) HIV infections in US populations have raised concerns about the sensitivity of subtype B virus-based donor screening and diagnostic assays. This study was designed to determine the prevalence and genetic diversity of HIV subtypes in US blood donors over the last two decades. STUDY DESIGN AND METHODS Three groups were studied: hemophiliacs infected by clotting factor concentrates in the early 1980s (n = 49), blood donors retrospectively identified as being seropositive in 1985 (n = 97), and blood donors identified as seropositive between 1993 and 1996 (n = 405). Subtype assignment was based primarily on heteroduplex mobility analysis (HMA) of HIV-1 env, with DNA sequence confirmation of selected specimens. HIV peptide-based EIA serotyping was used to rule out HIV-2 and group O infections and to serotype HMA-refractory specimens. RESULTS Of 551 specimens, 535 (97%) were assigned subtypes; 532 (99%) of these were subtype B. Three postscreening donations (1%) were assigned non-B subtypes (2 A, 1 C). Two of these three donors were born in Africa; the third was born in the United States and reported no risk factors other than heterosexual activity. HMA distribution plots showed an increase in env diversity among HIV-1 group B strains over time. CONCLUSION The results support the need for continued surveillance of HIV subtype diversity and ongoing validation of the sensitivity of HIV diagnostic assays to non-B subtype infections.
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Eckes B, Zigrino P, Kessler D, Holtkötter O, Shephard P, Mauch C, Krieg T. Fibroblast-matrix interactions in wound healing and fibrosis. Matrix Biol 2000; 19:325-32. [PMID: 10963993 DOI: 10.1016/s0945-053x(00)00077-9] [Citation(s) in RCA: 176] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The regulation of matrix deposition is a key event in many physiological and pathological situations. It involves the activity of mediators in autocrine and paracrine fashions and the contact of cells with the surrounding extracellular matrix as well. The tightly regulated balance of both mechanisms guarantees rapid and adaptive cellular responses to meet changes in the biological requirements of the environment. Disturbances lead to wound healing defects or the development of fibrosis. The molecular mechanisms for these regulatory events are only partially understood, but involve the activity of integrins and a structural continuum of extracellular matrix-receptor-cytoskeleton-nucleus for transfer of information and the regulation of activated genes.
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Clausen T, Kaiser JT, Steegborn C, Huber R, Kessler D. Crystal structure of the cystine C-S lyase from Synechocystis: stabilization of cysteine persulfide for FeS cluster biosynthesis. Proc Natl Acad Sci U S A 2000; 97:3856-61. [PMID: 10760256 PMCID: PMC18106 DOI: 10.1073/pnas.97.8.3856] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
FeS clusters are versatile cofactors of a variety of proteins, but the mechanisms of their biosynthesis are still unknown. The cystine C-S lyase from Synechocystis has been identified as a participant in ferredoxin FeS cluster formation. Herein, we report on the crystal structure of the lyase and of a complex with the reaction products of cystine cleavage at 1.8- and 1.55-A resolution, respectively. The sulfur-containing product was unequivocally identified as cysteine persulfide. The reactive persulfide group is fixed by a hydrogen bond to His-114 in the center of a hydrophobic pocket and is thereby shielded from the solvent. Binding and stabilization of the cysteine persulfide represent an alternative to the generation of a protein-bound persulfide by NifS-like proteins and point to the general importance of persulfidic compounds for FeS cluster assembly.
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83
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Browning JR, Hatfield E, Kessler D, Levine T. Sexual motives, gender, and sexual behavior. ARCHIVES OF SEXUAL BEHAVIOR 2000; 29:135-153. [PMID: 10842722 DOI: 10.1023/a:1001903705153] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The roles of gender and the sexual motives of Love, Pleasure, Conformity, Recognition, Dominance, and Submission in numerous usual and unusual sexual behaviors were investigated. In a survey of 191 college undergraduates it was found that Love, Pleasure, Conformity, and Recognition motives, often in interaction with gender, were all important predictors of sexual behavior. Gender was the best predictor of initiating usual sexual behavior, whereas the Love motive was the best predictor of actually engaging in usual sexual behavior. Pleasure and Recognition in interaction with gender were the best predictors of engaging in unusual sexual behavior. None of the sexual motives predicted initiating unusual sexual behavior. Findings suggest that a variety of sexual motives may underlie sexual behavior.
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Constantinides PP, Lambert KJ, Tustian AK, Schneider B, Lalji S, Ma W, Wentzel B, Kessler D, Worah D, Quay SC. Formulation development and antitumor activity of a filter-sterilizable emulsion of paclitaxel. Pharm Res 2000; 17:175-82. [PMID: 10751032 DOI: 10.1023/a:1007565230130] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE Paclitaxel is currently administered i.v. as a slow infusion of a solution of the drug in an ethanol:surfactant:saline admixture. However, poor solubilization and toxicity are associated with this drug therapy. Alternative drug delivery systems, including parenteral emulsions, are under development in recent years to reduce drug toxicity, improve efficacy and eliminate premedication. METHODS Paclitaxel emulsions were prepared by high-shear homogenization. The particle size of the emulsions was measured by dynamic light scattering. Drug concentration was quantified by HPLC and in vitro drug release was monitored by membrane dialysis. The physical stability of emulsions was monitored by particle size changes in both the mean droplet diameter and 99% cumulative distribution. Paclitaxel potency and changes in the concentration of known degradants were used as chemical stability indicators. Single dose acute toxicity studies were conducted in healthy mice and efficacy studies in B 16 melanoma tumor-bearing mice. RESULTS QW8184, a physically and chemically stable sub-micron oil-in-water (o/w) emulsion of paclitaxel, can be prepared at high drug loading (8-10 mg/mL) having a mean droplet diameter of <100 nm and 99% cumulative particle size distribution of <200 nm. In vitro release studies demonstrated low and sustained drug release both in the presence and absence of human serum albumin. Based on single dose acute toxicity studies, QW8184 is well tolerated both in mice and rats with about a 3-fold increase in the maximum-tolerated-dose (MTD) over the current marketed drug formulation. Using the B16 mouse melanoma model, a significant improvement in drug efficacy was observed with QW8184 over Taxol. CONCLUSIONS QW8184, a stable sub-micron o/w emulsion of paclitaxel has been developed that can be filter-sterilized and administered i.v. as a bolus dose. When compared to Taxol, this emulsion exhibited reduced toxicity and improved efficacy most likely due to the composition and dependent physicochemical characteristics of the emulsion.
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85
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McClellan M, Kessler D. Spending growth rates: are the differences real? Health Aff (Millwood) 1999; 18:250-2. [PMID: 10650710 DOI: 10.1377/hlthaff.18.6.250-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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86
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Ardehali A, Kessler D, Foroushani F, Laks H. Multivessel coronary artery bypass surgery without cardiopulmonary bypass. Am Heart J 1999; 138:983-6. [PMID: 10539833 DOI: 10.1016/s0002-8703(99)70027-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
BACKGROUND There is limited experience with complete myocardial revascularization on a beating heart. Using a mechanical stabilization system, we sought to determine if complete coronary revascularization is feasible without cardiopulmonary bypass and what the short-term clinical outcome would be. METHODS From February through September 1998, 26 patients underwent complete myocardial revascularization with Medtronics Octopus Tissue Stabilization System. Mean age for the group was 62 +/- 7 years (range 48 to 78 years); 11% had prior interventions. Mean preoperative ejection fraction was 49% +/- 14% (range 20% to 66%); 38% of operations were performed urgently. The mean number of vessels grafted was 3.0 +/- 0.9 (range 1 to 5 grafts/patient). In 96% of patients, at least one arterial graft was used. Fifteen percent of patients had 2 or more arterial grafts. In 58% of patients, a branch of circumflex coronary artery was bypassed. RESULTS The median time to extubation was 2 hours (range 0 to 37 hours). None of the patients had perioperative myocardial infarction, cerebrovascular accident, or renal failure requiring dialysis. The 30-day survival rate was 100%. Angiographic follow-up was not available. At a mean follow-up period of 3.8 +/- 2.9 months, all patients remained free of angina and none has required cardiac reintervention. CONCLUSIONS Complete myocardial revascularization on a beating heart can be achieved with the currently available stabilization systems and is associated with low perioperative complications and satisfactory short-term clinical outcomes. The long-term outcomes and graft patency remain to be determined.
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Kessler D, Hatz C, Schär A. [Parallel use of medical services? Patterns of using complementary medicine and biomedicine]. PRAXIS 1999; 88:1113-1119. [PMID: 10429549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
In order to identify behavioural patterns within the pluralistic medical system, 38 patients have been observed over a period of two years. The most notable quality of behaviour is its flexibility. Single patients use complementary medicine and biomedicine in pragmatic and differentiated ways that change over time. Parallelism can be observed among the offered medical services, while their use is to be divided into parallel, alternate, alternative and complementary forms. Phases of exclusive use of complementary medicine occur, but during the two year period under investigation, all patients have made use of biomedicine.
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88
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Kessler S, Kessler D, Frishman WH. Antiplatelet therapy: glycoprotein IIb/IIIa receptor antagonists. Drugs Today (Barc) 1999; 35:413-8. [PMID: 12973387 DOI: 10.1358/dot.1999.35.6.544927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
The glycoprotein IIb/IIIa antagonists are potent drugs that inhibit platelet aggregation. They are formulated as monoclonal antibodies and synthetic peptides for intravenous use in patients undergoing high-risk angioplasty procedures and in patients with unstable coronary syndromes. Orally active agents are now being evaluated in clinical trials.
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McClellan M, Kessler D. A global analysis of technological change in health care: the case of heart attacks. The TECH Investigators. Health Aff (Millwood) 1999; 18:250-5. [PMID: 10388222 DOI: 10.1377/hlthaff.18.3.250] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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90
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Kessler D, Lloyd K, Lewis G, Gray DP. Cross sectional study of symptom attribution and recognition of depression and anxiety in primary care. BMJ (CLINICAL RESEARCH ED.) 1999; 318:436-9. [PMID: 9974461 PMCID: PMC27737 DOI: 10.1136/bmj.318.7181.436] [Citation(s) in RCA: 243] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/16/1998] [Indexed: 11/03/2022]
Abstract
OBJECTIVES To examine the effect of patients' causal attributions of common somatic symptoms on recognition by general practitioners of cases of depression and anxiety and to test the hypothesis that normalising attributions make recognition less likely. DESIGN Cross sectional survey. SETTING One general practice of eight doctors in Bristol. SUBJECTS 305 general practice attenders. MAIN OUTCOME MEASURE The rate of detection by general practitioners of cases of depression and anxiety as defined by the general health questionnaire. RESULTS Consecutive attenders completed the general health questionnaire and the symptom interpretation questionnaire, which scores style of symptom attribution along the dimensions of psychologising, somatising, and normalising. General practitioners detected depression or anxiety in 56 (36%; 95% confidence interval 28% to 44%) of the 157 patients who scored highly on the general health questionnaire. Subjects with a normalising attributional style were less likely to be detected as cases; doctors did not make any psychological diagnosis in 46 (85%; 73% to 93%) of 54 patients who had high questionnaire and high normalising scores. Those with a psychologising style were more likely to be detected; doctors did not detect 21 (38%; 25% to 52%) of 55 patients who had high questionnaire and high psychologising scores. The somatisation scale was not associated with low detection rates. This pattern of results persisted after adjustment for age, sex, general health questionnaire score, and general practitioner. CONCLUSIONS Normalising attributions minimise symptoms and are non-pathological in character. The normalising attributional style is predominant in general practice attenders and is an important cause of low rates of detection of depression and anxiety.
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Lang T, Kessler D. Evidence for cysteine persulfide as reaction product of L-Cyst(e)ine C-S-lyase (C-DES) from Synechocystis. Analyses using cystine analogues and recombinant C-DES. J Biol Chem 1999; 274:189-95. [PMID: 9867829 DOI: 10.1074/jbc.274.1.189] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The pyridoxal phosphate-dependent monomeric L-cysteine/cystine C-S-lyase (C-DES), previously isolated from Synechocystis PCC 6714 by its capacity to direct [2Fe-2S] cluster assembly of ferredoxin in vitro (Leibrecht, I., and Kessler, D. (1997) J. Biol. Chem. 272, 10442-10447), has now been cloned, sequenced, and overexpressed in Escherichia coli. The amino acid sequence of C-DES was found to be nearly identical (92% identity) to the open reading frame slr2143 of Synechocystis PCC 6803 and showed a more distant relationship to the NifS family of proteins (about 27% identity). Recombinant C-DES displayed activities equal to the isolate from Synechocystis in terms of the cyst(e)ine lyase reaction and holoferredoxin formation which recommended its use for functional and mechanistic studies. Investigation of the substrate spectrum for beta-elimination found L-cysteine to be a poor substrate (kcat approximately 0.15 s-1) in contrast to L-cystine (kcat = 36 s-1) and several related compounds. Of these compounds, desaminocystine (S-(carboxyethylthio)-L-cysteine) was used for C-DES-mediated persulfide generation. Stabilization of the linear persulfide 3-(disulfanyl)-propionic acid was achieved by cyclization as a novel intramolecular trapping reaction; this yielded 1,2-dithiolan-3-one which was isolated and identified by chemical analyses.
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Eckes B, Kessler D, Aumailley M, Krieg T. Interactions of fibroblasts with the extracellular matrix: implications for the understanding of fibrosis. SPRINGER SEMINARS IN IMMUNOPATHOLOGY 1999; 21:415-29. [PMID: 10945034 DOI: 10.1007/s002810000034] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The cellular organization and the compartmentalization in multicellular organisms is mediated by the extracellular matrix (ECM). This structure is composed by a wide variety of different macromolecules which carry distinct domains with defined structural and/or biological activities. Cells are known to interact with these molecules via specific receptors. Following activation, these receptors transduce signals either directly to the intracellular cytoskeleton or via different signalling cascades. Cell-matrix interactions, therefore, not only control the shape and orientation of cells but can also directly regulate cellular functions, including migration, differentiation, proliferation, and the expression of different genes. These cell-matrix interactions have been elucidated in detail for several biological processes, especially morphogenesis and differentiation, but also play an important role during pathological situations, e.g. wound healing and tumor progression. Although much less investigated, similar mechanisms are thought to regulate the biological behavior of fibroblastic cells, the final target cells in fibrosis. The activity of these cells depends in various ways on the presence of ECM molecules. First, some of the molecules are known to bind to and modulate the activity of those growth factors and cytokines, which lead to the activation of fibroblasts during the early phases of fibrosis. Second, deposition of large amounts of ECM molecules alters the environment and the mechanical load on the cells which are embedded in this matrix. Third, ECM molecules directly modulate fibroblast metabolism via certain integrin receptors. This review summarizes recent developments in all three domains. It mainly focuses on the direct role of ECM molecules in the biosynthetic activity of fibroblasts.
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94
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Drescher J, Kruse A, Kessler D, Stork W, Müller-Glaser KD, Kreiner CF. [Micro-optic tonometer]. BIOMED ENG-BIOMED TE 1998; 43 Suppl:566-7. [PMID: 9859494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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96
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Forsberg F, Roy R, Merton DA, Rawool NM, Liu JB, Huang M, Kessler D, Goldberg BB. Conventional and hypobaric activation of an ultrasound contrast agent. ULTRASOUND IN MEDICINE & BIOLOGY 1998; 24:1143-1150. [PMID: 9833583 DOI: 10.1016/s0301-5629(98)00062-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Hypobaric activation is a new injection technique for use with the contrast agent EchoGen and, in this study, the agent's ability to produce parenchymal enhancement in vivo, with and without prior hypobaric activation, was investigated. Injections, ranging in dose from 0.05 to 0.5 mL/kg, were administrated through a peripheral vein to eight woodchucks with multiple hepatomas. At the 0.10 mL/kg dose level, seven of eight injections following hypobaric activation (88%) resulted in definite parenchymal enhancement. Conversely, dosages of 0.10 mL/kg without prior hypobaric activation produced no grey-scale changes. Only at the 0.4 and 0.5 mL/kg dosage level did the conventional administration technique obtain similar results (4 of 5 injections increased the echogenicity for a 0.4 mL/kg dose). These differences were statistically significant (p = 0.031). In vitro experiments were conducted to establish the physical mechanisms behind hypobaric activation. Relative measurements of contrast microbubble sizes were performed with a phase Doppler particle analyzer after hypobaric and after conventional (bolus) activation. Hypobaric activation produced approximately 20 times more microbubbles per unit volume than the conventional method. In conclusion, this investigation has demonstrated the benefits of prior hypobaric activation when performing in vivo contrast studies with EchoGen and determined the physical mechanisms behind this new injection technique. Hypobaric activation of EchoGen increases contrast enhancement and reduces dose size.
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97
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Balentine JR, Gaeta TJ, Kessler D, Bagiella E, Lee T. Effect of 50 milliliters of 50% dextrose in water administration on the blood sugar of euglycemic volunteers. Acad Emerg Med 1998; 5:691-4. [PMID: 9678393 DOI: 10.1111/j.1553-2712.1998.tb02487.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE To evaluate the effect of administration of 1 ampule of 50% dextrose in water solution (D50W) on serum glucose levels in healthy adult volunteers, the authors set out to determine whether a pre-D50W serum glucose level can be predicted from the ED sample. METHODS This was a prospective, interventional study conducted from the ED of an urban, university-affiliated hospital. All subjects were healthy employee volunteers between 25 and 40 years of age. Baseline serum glucose levels were determined and all subjects were given an i.v. bolus of 25 grams of 50% dextrose solution. The main outcome measures were post-D50W serum glucose levels (observed) at 5 predetermined time intervals (5 min, 15 min, 30 min, 1 hr, and 2 hr). An expected change in serum glucose was calculated using the volume of distribution formula for glucose. RESULTS Twenty-five volunteers (17 males and 8 females) participated in the study. The mean baseline serum glucose was 82.3 +/- 13.5 mg/dL. The mean post-infusion levels were: 244.4 +/- 44.6 mg/dL (5 min), 145.8 +/- 52.3 mg/dL (15 min), 88.1 +/- 28.8 mg/dL (30 min), 77.6 +/- 13.6 mg/dL (60 min), and 83.2 +/- 11.4 mg/dL (120 min). Using a mixed-effect regression model, statistically significant increases in serum glucose levels were found at 5 minutes (p < 0.001) and 15 minutes (p < 00001) following administration of D50W. There was a return to baseline serum glucose by 30 minutes. The expected change based on the volume of distribution formula (53.7 +/- 34.9) did not correlate with the observed changes at any measured time interval. CONCLUSION Without pre-intervention blood drawing by emergency medical services, it is not possible to accurately predict pre-D50W serum glucose levels based on post-D50W glucose levels. The diagnosis of hypoglycemia as the etiology of altered mental status must therefore remain a diagnosis of exclusion. In addition, the return of serum glucose to baseline after 30 minutes suggests the duration of the effect of 1 ampule of D50W. Frequent re-evaluation of the serum glucose levels of suspected or proven hypoglycemic patients after administration of D50W should be considered.
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Drescher J, Kruse A, Kessler D, Stork W, Müller-Glaser KD, Kreiner C. Mikrooptisches Tonometer. BIOMED ENG-BIOMED TE 1998. [DOI: 10.1515/bmte.1998.43.s1.566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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99
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Dransfield D, Kessler D, McCarthy C. Respiratory syncytial virus PREVENT Study questions. Pediatrics 1997; 100:1044-5. [PMID: 9411387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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100
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Amandus HE, Hendricks SA, Zahm D, Friedmann R, Block C, Wellford C, Brensilber D, Bynum T, McManus R, Malcan J, Weiss JC, Kessler D. Convenience store robberies in selected metropolitan areas. Risk factors for employee injury. J Occup Environ Med 1997; 39:442-7. [PMID: 9172089 DOI: 10.1097/00043764-199705000-00010] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Circumstances of injury were abstracted from police reports for 1835 convenience store robberies that occurred during 1992 or 1993 in selected metropolitan areas of seven eastern states. Subset analyses were performed using the data (758 robberies) from four states with relatively complete risk factor information. The purpose of this study was to estimate the risk of injury in a robbery situation for various risk factors. The overall risk of employee robbery-related injury could not be estimated because the probability of robbery is unknown. Of the 1835 robberies, 59% of the total robberies occurred at nighttime (9 p.m. to 3 a.m.), 47% occurred in stores previously robbed in the study period, 63% involved the use of a firearm, and 12% were associated with an injury to at least one employee. In the subset analysis of 758 robberies in four states, the employee probability of injury in a robbery was lower with firearm use compared with no weapon or use of a blunt instrument, and the probability of severe injury (defined as death, or an injury necessitating a trip to a hospital) was lower with a firearm compared with the use of a blunt instrument. However, all five fatalities were firearm-related. Other factors that were associated with a lower probability of employee injury included robbery occurrence in stores that had been robbed multiple times, compared with stores robbed only once; having 1 to 999 dollars stolen, compared with having no money stolen; and the presence of a customer(s) in the store at the time of the robbery. The employee risk of injury was not significantly different between one- (0.106) and multiple-employee (0.111) stores. Similarly, the employee risk of severe injury was not significantly different between one- (0.029) and multiple-employee stores (0.022). We conclude that there are several potential risk factors for employee injury in convenience store robberies, some of which are amenable to interventions. Further research on these factors and their relationship to employee injury is indicated.
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