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Spies CD, Schulz CM, Weiss-Gerlach E, Neuner B, Neumann T, von Dossow V, Schenk M, Wernecke KD, Elwyn G. Preferences for shared decision making in chronic pain patients compared with patients during a premedication visit. Acta Anaesthesiol Scand 2006; 50:1019-26. [PMID: 16923100 DOI: 10.1111/j.1399-6576.2006.01097.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND There is some evidence that patients' outcomes improve if they are involved in shared decision making (SDM). A chronic pain clinic or premedication visit could be adequate settings for the implementation of SDM. So far, the patients' preference for involvement in decision making and their desire for information have not been tested in anesthesiological settings. METHODS A group of chronic pain patients was compared with a group of patients in the premedication visit with respect to SDM, the desire for information and perceived involvement in care. The autonomy preference index (API, measuring preference for involvement and desire for information) and the perceived involvement in care scale (PICS, measuring patients' perception of easier involvement by doctors and information exchange) were administered. RESULTS In total, 190 chronic pain patients and 151 patients of premedication were included in this study. Patient of the premedication visit had significantly higher SDM scores. Desire for information was high, but there were no differences between groups. Younger patients [B (estimate) =- 0.3; 95% CI (-0.4) - (-0.1)], women (B = 10.9; 95% CI 6.3-15.4) and patients with higher educational level (B = 10.1; 95% CI 5.6-14.6) had more desire for SDM. PICS scores were basically influenced by groups: chronic pain patients felt more facilitated by doctors [B =- 0.185; 95% CI (-0.4) - (-0.1)] and had more information exchange [B =- 19.5; 95% CI (-15.8) - (-2.4)] than patients in the premedication visit. CONCLUSION In both anesthesiological settings, the desire for information was high, but patients in the premedication visit had higher SDM scores, especially young female patients with higher educational level. Real patient-physician interaction showed that premedication patients felt less involved by doctors and had less information exchange compared with the chronic pain patients. Therefore, premedication visits should be focussed more on adequate information exchange and involvement of the patient in the shared decision making process.
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Hermann K, Schulte E, Hagmeister H, Arnold G, Schenk M, Kopf A, Willich SN. Behandlungserfolg und Zufriedenheit chronischer Schmerzpatienten/innen in Einrichtungen der Speziellen Schmerztherapie. DAS GESUNDHEITSWESEN 2005. [DOI: 10.1055/s-2005-920713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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78
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Lim U, Schenk M, Kelemen LE, Davis S, Cozen W, Hartge P, Ward MH, Stolzenberg-Solomon R. Dietary determinants of one-carbon metabolism and the risk of non-Hodgkin's lymphoma: NCI-SEER case-control study, 1998-2000. Am J Epidemiol 2005; 162:953-64. [PMID: 16221809 DOI: 10.1093/aje/kwi310] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
The role of dietary one-carbon determinants remains largely unexplored for non-Hodgkin's lymphoma (NHL). In a population-based case-control study of non-African-American adult (aged 20-74 years) women and men from four US Surveillance, Epidemiology, and End Results study centers (Detroit, Michigan; Iowa; Los Angeles, California; and Seattle, Washington; 1998-2000), the authors examined folate; vitamins B2, B6, and B12; methionine; and a one-carbon antagonist, alcohol, in 425 incident NHL cases and 359 controls who completed a detailed food frequency questionnaire. Adjusted odds ratios and 95% confidence intervals were estimated by using unconditional logistic regression. Higher intake of one-carbon determinants from food was associated with a lower risk of NHL, but that for only vitamin B6 (highest vs. lowest quartile: odds ratio = 0.57, 95% confidence interval: 0.34, 0.95; p trend = 0.01) and methionine (odds ratio = 0.49, 95% confidence interval: 0.31, 0.76; p trend = 0.002) reached statistical significance. Folate from food was inversely associated with diffuse subtype (odds ratio = 0.47, 95% confidence interval: 0.23, 0.94; p trend = 0.03). The authors found no association between total (food plus supplement) vitamins and NHL. Nonusers of alcohol had an elevated NHL risk compared with users, and alcohol did not modify other nutrient-NHL associations. Findings suggest that one-carbon nutrients, particularly vitamin B6 and methionine, may be protective against NHL.
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Pereira PL, Aubé C, Schmidt D, Schenk M, Brieger J, Helmberger T, Schick F, Claussen CD. MR-gesteuerte Radiofrequenz (RF)-Ablation: Vergleichende, experimentelle Phantom-Studie zur Bestimmung der Wertigkeit von Artefakten sechs unterschiedlicher MR-kompatibler RF-Sonden. ROFO-FORTSCHR RONTG 2004. [DOI: 10.1055/s-2004-828009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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80
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Hehlmann R, Berger U, Pfirrmann M, Hochhaus A, Metzgeroth G, Maywald O, Hasford J, Reiter A, Hossfeld DK, Kolb HJ, Löffler H, Pralle H, Queisser W, Griesshammer M, Nerl C, Kuse R, Tobler A, Eimermacher H, Tichelli A, Aul C, Wilhelm M, Fischer JT, Perker M, Scheid C, Schenk M, Weiss J, Meier CR, Kremers S, Labedzki L, Schmeiser T, Lohrmann HP, Heimpel H. Randomized comparison of interferon alpha and hydroxyurea with hydroxyurea monotherapy in chronic myeloid leukemia (CML-study II): prolongation of survival by the combination of interferon alpha and hydroxyurea. Leukemia 2003; 17:1529-37. [PMID: 12886239 DOI: 10.1038/sj.leu.2403006] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The optimum treatment conditions of interferon (IFN) alpha therapy in chronic myeloid leukemia (CML) are still controversial. To evaluate the role of hydroxyurea (HU) for the outcome of IFN therapy, we conducted a randomized trial to compare the combination of IFN and HU vs HU monotherapy (CML-study II). From February 1991 to December 1994, 376 patients with newly diagnosed CML in chronic phase were randomized. In all, 340 patients were Ph/BCR-ABL positive and evaluable. Randomization was unbalanced 1:2 in favor of the combination therapy, since study conditions were identical to the previous CML-study I and it had been planned in advance to add the HU patients of study I (n=194) to the HU control group. Therefore, a total of 534 patients were evaluable (226 patients with IFN/HU and 308 patients with HU). Analyses were according to intention-to-treat. Median observation time of nontransplanted living patients was 7.6 years (7.9 years for IFN/HU and 7.3 years for HU). The risk profile (new CML score) was available for 532 patients: 200 patients (38%) were low, 239 patients (45%) intermediate, and 93 patients (17%) high risk. Complete hematologic response rates were higher in IFN/HU-treated patients (59 vs 32%). Of 169 evaluable IFN/HU-treated patients (75%), 104 patients (62%) achieved a cytogenetic response that was complete in 12% (n=21), major in 14% (n=24), and at least minimal in 35% (n=59). Of the 534 patients, 105 (20%) underwent allogeneic stem cell transplantation in first chronic phase. In the low-risk group, 65 of 200 patients were transplanted (33%), 30 (13%) in the intermediate-risk group, and nine (10%) in the high-risk group. Duration of chronic phase was 55 months for IFN/HU and 41 months for HU (P<0.0001). Median survival was 64 months for IFN/HU and 53 months for HU-treated patients (P=0.0063). We conclude that IFN in combination with HU achieves a significant long-term survival advantage over HU monotherapy. In view of the data of CML-study I, these results suggest that IFN/HU is also superior to IFN alone. HU should be combined with IFN in IFN-based therapies and for comparisons with new therapies.
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Gambichler T, Bader A, Vojvodic M, Avermaete A, Schenk M, Altmeyer P, Hoffmann K. Plasma levels of opioid peptides after sunbed exposures. Br J Dermatol 2002; 147:1207-11. [PMID: 12452872 DOI: 10.1046/j.1365-2133.2002.04859.x] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Previous studies have indicated that solar and artificial ultraviolet (UV) radiation have a positive influence on psychological variables such as mood and emotional state. Circulating opioid peptides have been suggested as being important in this effect. OBJECTIVES To investigate in a controlled trial the influence of UVA radiation on opioid peptide levels. METHODS We determined plasma levels of beta-endorphin immunoreactive material (IRM) and met-enkephalin in UV-exposed (n = 35) and non-exposed (n = 9) healthy volunteers. On the first day of the study, blood samples were taken from the volunteers (time A). UVA irradiation was subsequently administered with an air-conditioned tanning device. During the UV exposures the volunteers wore opaque goggles. Twenty minutes after UV exposure, blood samples were collected again (time B). Within the following 3 weeks the volunteers had a series of five UV exposures. On the last day of the study (24 h after the sixth UV exposure) blood samples were collected (time C). The cumulative UVA doses were 96 J cm-2 for skin type II and 126 J cm-2 for skin type III. The controls had no UV exposures. Plasma beta-endorphin IRM and met-enkephalin levels were determined using radioimmunoassays. RESULTS At all times of blood collection (A, B, C), there were no significant differences in plasma levels of beta-endorphin IRM and met-enkephalin between UV-exposed and non-exposed volunteers (P > 0.05). CONCLUSIONS UVA irradiation does not significantly elevate plasma levels of beta-endorphin IRM and met-enkephalin. Therefore we suggest that psychological benefits claimed to occur after UV exposure are unlikely to be mediated by the types of circulating opioid peptides measured in this study.
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Eilers K, Schenk M, Putzier M, Volk T, Kox WJ, Zippel H. [Use of peridural catheters in the treatment of postoperative pain after spinal instrumentated fusion--an experience report]. ZEITSCHRIFT FUR ORTHOPADIE UND IHRE GRENZGEBIETE 2002; 140:621-5. [PMID: 12476384 DOI: 10.1055/s-2002-36043] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
AIM In a prospective randomized clinical study we investigated in a group of 20 patients after spinal instrumentation surgery the analgesic efficacy and the safety of epidural analgesia. Intraoperatively an epidural catheter was placed by the orthopedic surgeons for postoperative pain control. METHOD For epidural catheter analgesia a mixture of the local anesthetic ropivacaine and the opioid sufentanil was used with an initial bolus, followed by a continuous infusion and the possibility of patient-controlled bolus administration (PCEA). Pain-scores (VAS) were measured pre- and postoperatively at rest, and during active mobilization maneuvers like turning around in bed and standing. The neurological status, side effects, and complications were evaluated. RESULTS Mean pain-scores (VAS) were 3.8 pre-operatively at rest, after initiation of epidural analgesia 0.3 at rest, 1.6 at turning around in bed and 0.8 at standing (6.8 pre-operatively). Transient sensible or motoric deficits, due to the local anesthetics' effect, occurred in 8 respectively in 3 of the patients. Drug-induced typical side-effects were pruritus, nausea and emesis. No cardiopulmonary complications happened. CONCLUSION The epidural lumbal analgesia is an effective and safe method to control postoperative pain after spinal instrumentation surgery. Precondition is the knowledge about the safe and standardized technique of intraoperative catheter placement by the orthopedic surgeon, the choice of the appropriate analgesic drugs and a good cooperation between the departments of anesthesiology and orthopedic surgery and nursing staff.
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Linti C, Zipfel A, Schenk M, Dauner M, Doser M, Viebahn R, Becker HD, Planck H. Cultivation of porcine hepatocytes in polyurethane nonwovens as part of a biohybrid liver support system. Int J Artif Organs 2002; 25:994-1000. [PMID: 12456041 DOI: 10.1177/039139880202501014] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Many patients suffering from end-stage liver disease cannot be transplanted within reasonable time due to the shortage of donor organs. Bioartificial liver support systems may contribute to the liver regeneration or bridging the time until a liver graft for transplantation becomes available. Nonwovens with integrated oxygenation capacity have been developed and manufactured by melt blow technology using thermoplastic polyurethane. Capillary membranes for oxygenation were integrated into the nonwoven during the processing. The polyurethane nonwoven structures with adapted pore size and high pore volume allow high cell densities in the hepatocyte culture. The three-dimensional cell culture was housed by a flow bioreactor system and was integrated in a closed loop circulation with monitoring possibilities for pressure, pH, temperature, ammonia, and oxygen. Hepatocytes were isolated from rats or pigs by collagenase perfusion and infused into the medium-perfused circulation. Cells showed high viability and hepatocyte specific cytochrome P450-dependent metabolic function in culture (MEGX test).
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85
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Schenk M, Zipfel A, Grenz A, Dieter Becker H, Viebahn R. Cytokine release from liver grafts during cold ischemia. Transplant Proc 2001; 33:3722-3. [PMID: 11750586 DOI: 10.1016/s0041-1345(01)02519-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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86
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Zipfel A, Schenk M, Metzdorf B, Bode C, Viebahn R. Release of TNF-alpha from lipopolysaccharide (LPS)-stimulated Kupffer cells in serum- and nutrient-free medium. Inflammation 2001; 25:287-92. [PMID: 11820455 DOI: 10.1023/a:1012856408531] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
In monocytes/macrophages LPS stimulation occurs by the binding of LPS and the serum component LPS-binding protein (LBP) to CD14. This study was conducted to investigate whether this mechanism also occurs in Kupffer cells. Rat Kupffer cells were stimulated for up to 8 h by LPS (0, 100 ng/ml, 10 microg/ml) in RPMI medium or in nutrient-free Krebs-Henseleit (KH) buffer. Some incubations were performed without serum, while in others serum was provided. TNF-alpha concentrations of the supernatants were measured by ELISA. LPS stimulation of Kupffer cells yielded the following results. In KH without any additives a considerable amount of TNF-alpha was released. Incubation in RPMI without serum caused twice as much TNF-alpha to be released as when KH was used. The addition of autologous serum to RPMI did not increase TNF-alpha response. These results provide evidence that a substantial part of TNF-alpha release by LPS-stimulated Kupffer cells occurs in a serum- and thus LBP-independent way.
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Abstract
Because transplantation success is influenced by the quality of the graft, the objective of this study was to find parameters to evaluate transplant livers in the recipient centre. In 64 liver grafts, the venous effluates of a portal back-table flush were investigated for various parameters. Amongst them, glutathione S-transferase (GST), glutamate dehydrogenase (GLDH) and the leucocyte count were found superior in predicting graft survival. Using the combination of these parameters, 100-day graft survival of between 95% (all parameters positive) and 0% (all parameters negative) was predicted. We concluded that good liver grafts are characterized by a low width of injury (cytosolic component: GST), a low depth of injury (mitochondrial component: GLDH), as well as by a potential to induce tolerance (passenger leucocytes). Perfusate analysis seems to be a valuable tool to recognize problematic grafts in advance and to quantify the "graft factor" in considerations concerning quality control.
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88
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Müller J, Schenk M, Zipfel A, Lauchart W, Viebahn R. Influence of perioperative sHLA I concentrations on the histological development of the liver graft. Transpl Int 2001; 13 Suppl 1:S449-51. [PMID: 11112051 DOI: 10.1007/s001470050380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Soluble HLA I (sHLA I) in human serum are ascribed an immunoregulatory role in the context of organ transplantation. Based on histological findings, the objective of the current study was to evaluate the protective influence of sHLA I in liver transplantation from the time point of reperfusion. The sHLA I concentrations in serum samples derived from the liver vein immediately after reperfusion (flush catheter) of 38 patients with liver transplantations were determined by ELISA. The postoperative histological findings of the transplant biopsies were categorized according to rejection, endothelialitis, cholestasis, and necrosis, as well as fatty degeneration. An evaluation according to Kaplan-Meier showed a lower incidence for all of these factors in liver grafts with high sHLA concentrations (P < 0.05). We conclude that low sHLA I concentrations during reperfusion correlate with later complications, thus indicating that sHLA I may have protective potential in liver transplantation.
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Schenk M, Zipfel A, Schulz C, Becker HD, Viebahn R. RANTES in the postoperative course after liver transplantation. Transpl Int 2001; 13 Suppl 1:S147-9. [PMID: 11111984 DOI: 10.1007/s001470050307] [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: 10/28/2022]
Abstract
RANTES (regulated upon activation, normal T-cell expressed and secreted), an inflammatory cytokine, promotes accumulation and activation of leukocytes. In 67 liver transplantations, systemic concentrations of RANTES were correlated to graft survival and incidence of rejection. RANTES levels either increased to highly elevated levels at day 14 (84 +/- 64 ng/ml; group 1; n = 43) or remained within the limit of healthy controls (19 +/- 11 ng/ml at day 14; group 2; n = 24). The 100-day graft function rate was 0.91 in group 1 and 0.63 in group 2 (P = 0.002). The risk ratio for rejection during the first 100 days was increased 2.2-fold in group 2 compared to group 1 (P = 0.02). High postoperative release of RANTES after liver transplantation, a beneficial factor, may reflect a general systemic immunological activation. It can be concluded that high early systemic RANTES levels may play a role in immunological recognition leading to a tolerance of the liver graft.
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Zipfel A, Schenk M, You MS, Lauchart W, Bode C, Viebahn R. Endotoxemia in organ donors: graft function following liver transplantation. Transpl Int 2001; 13 Suppl 1:S286-7. [PMID: 11112014 DOI: 10.1007/s001470050343] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Translocation of endotoxin (LPS) to the portal-venous system is produced by multiple factors. In the case of normal liver function, LPS is rapidly cleared from the portal blood by Kupffer cells; in impaired liver function, LPS can reach the systemic circulation. The objective of this study was to investigate whether elevated donor endotoxin levels affect graft function in the recipient. LPS levels in donor plasma were measured in 14 consecutive liver transplantations. Grafts with donor LPS levels < or = 12 pg/ml had a function probability of 100% after 600 days (n = 10). LPS concentrations of > 12 pg/ml in donor plasma led to loss of function in 75% of the liver grafts (n = 4; P = 0.003; Wilcoxon). Elevated LPS values in donor plasma seem to impair the prognosis of the grafts and could predict poor graft function as early as at the time of brain death.
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91
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Roth LM, Schenk M, Bogdewic SP. Developing clinical teachers and their organizations for the future of medical education. MEDICAL EDUCATION 2001; 35:428-429. [PMID: 11328511 DOI: 10.1046/j.1365-2923.2001.00946.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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92
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Schenk M, Schwartz AG, O'Neal E, Kinnard M, Greenson JK, Fryzek JP, Ying GS, Garabrant DH. Familial risk of pancreatic cancer. J Natl Cancer Inst 2001; 93:640-4. [PMID: 11309441 DOI: 10.1093/jnci/93.8.640] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Pancreatic cancer is the fifth leading cause of cancer-related mortality in the United STATES: Although smoking and age are known risk factors for pancreatic cancer, several case reports and case-control studies have suggested that there is also a familial risk. We evaluated whether a family history of pancreatic cancer increases the risk of pancreatic cancer in first-degree relatives and whether smoking and younger age at cancer diagnosis further increase this risk. METHODS We conducted in-person interviews with 247 patients ("case probands") with pancreatic cancer and 420 population-based control probands to collect risk factor data and pancreatic cancer family history for 1816 first-degree relatives of the case probands and 3157 first-degree relatives of the control probands. We analyzed the data by unconditional logistic regression models, with adjustment for correlated data by use of generalized estimating equations. All statistical tests were two-sided. RESULTS A positive family history of pancreatic cancer (i.e., being related to a case proband) or ever-smoking cigarettes approximately doubled the risk of pancreatic cancer (relative risk [RR] = 2.49; 95% confidence interval [CI] = 1.32 to 4.69; RR = 2.04; 95% CI = 1.09 to 3.83, respectively). The RR increased to 8.23 (95% CI = 2.18 to 31.07) for relatives who ever smoked and were related to a case proband who was diagnosed before age 60 years. CONCLUSION Routine questioning of patients about a family history of pancreatic cancer, the age of onset of this cancer in their relatives, and the patient's smoking status may identify individuals at high risk of pancreatic cancer. Future research exploring the genetic and environmental interactions associated with the risk of pancreatic cancer is critically important.
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93
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Zipfel A, Schenk M, Grenz A, Lauchart W, Viebahn R. TNF-alpha and sCD14 as early markers of CMV susceptibility after liver transplantation. Transplant Proc 2001; 33:1794-5. [PMID: 11267515 DOI: 10.1016/s0041-1345(00)02683-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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94
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Schulz C, Schenk M, Zipfel A, Becker HD, Viebahn R. New aspects of RANTES in context of liver transplantation. Transplant Proc 2001; 33:414-5. [PMID: 11266889 DOI: 10.1016/s0041-1345(00)02073-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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95
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Schenk M, Seeger T, Leipertz A. Simultaneous temperature and relative O2-N2 concentration measurements by single-shot pure rotational coherent anti-stokes Raman scattering for pressures as great as 5 MPa. APPLIED OPTICS 2000; 39:6918-6925. [PMID: 18354704 DOI: 10.1364/ao.39.006918] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Dual-broadband pure rotational coherent anti-Stokes Raman scattering is a valuable nonintrusive tool for gas diagnosis that provides simultaneous and time-resolved information about temperature and relative species concentration. A systematic investigation of single-shot precision and accuracy of simultaneous measurement of temperature and O(2)/N(2) concentration is presented. Various O(2) concentrations (1.0-15.6%) in binary mixtures with N(2) have been investigated in a temperature range from 300 to 773 K and for pressures of 1-50 bars (0.1-5 MPa). A comparison of two least-sum-squared differences fit evaluation procedures for the spectral shape, weighted constantly or inversely with respect to the relative signal intensity, is given. The results yielded good accuracy and precision for measuring temperature as well as concentration. The influence of temperature, O(2) concentration, pressure, and evaluation techniques on both accuracy and precision is discussed.
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96
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Grenz A, Schenk M, Zipfel A, Viebahn R. TNF-alpha and its receptors mediate graft rejection and loss after liver transplantation. Clin Chem Lab Med 2000; 38:1183-5. [PMID: 11156356 DOI: 10.1515/cclm.2000.184] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Tumour necrosis factor-alpha (TNF-alpha) plays a pivotal role in the immune response and mediates inflammation by its receptors (TNF-RI and TNF-RII), as observed during rejection episodes and impaired graft function after liver transplantation. TNF-alpha and its receptors were analysed by an ELISA technique in serum samples from 77 consecutive liver transplantations in 63 patients. Samples were collected preoperatively from donors and recipients and then daily in the first two postoperative weeks. Peak levels of TNF-alpha and its soluble receptors (sTNF-RI and sTNF-RII) in the first and second postoperative week correlated with the extent of reperfusion injury. Impaired graft functions correlated with high sTNF-RI levels preoperatively (> 5 ng/ml, p = 0.01) and in the postoperative period (> 16 ng/ml, p = 0.02). Significantly increased TNF-alpha (> 25 pg/ml, p = 0.009) and sTNF-RI levels (> 5 ng/ml, p = 0.05) were found in donors of grafts with a high rejection risk. Elevated levels of TNF-alpha in the postoperative period correlated with an increased rejection risk (> 90 pg/ml, p = 0.02). The activity of the immune system with high concentrations of TNF-alpha and its receptors both in the recipient and the transplant donor seems to play an essential role in allograft development.
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Schenk M, Zipfel A, Kratt T, Petersen P, Becker HD, Viebahn R. The postoperative course of gamma-glutamyl transpeptidase--a marker of cytomegalovirus (CMV) replication risk? Clin Chem Lab Med 2000; 38:1181-2. [PMID: 11156355 DOI: 10.1515/cclm.2000.183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Cytomegalovirus (CMV) infection is a common complication in the postoperative course of liver transplantation. In order to start early prophylactic therapy, but to avoid unnecessary treatment, or expensive screening, a desirable goal in post-transplant monitoring is to find appropriate markers in standard laboratory diagnostics. In the present study, the results of a 6-week CMV replication monitoring schedule by the pp65 antigenemia assay in 100 liver graft recipients were included. The activities of transaminases, glutamate dehydrogenase and gamma-glutamyl transpeptidase (gamma-GT) were measured by routine laboratory methods. In contrast to the transaminases, the serum activity of gamma-GT increased during the first postoperative week. The maximum levels were 246 +/- 211 U/l in patients without (n = 46) and 140 +/- 89 U/l in patients with early CMV replication (n = 54; p = 0.02). Patients with gamma-GT levels below 200 U/l on the 5th postoperative day (n = 72) had a CMV replication risk of 65%, whereas those patients with gamma-GT levels above this threshold had a risk of 30% (n = 28; p = 0.0007; relative risk = 2.9). These findings provide a routinely usable marker for the identification of patients at an increased risk of CMV replication. It can be considered that these phenomena may be caused by an additional immunosuppressive effect of the CMV virus.
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Beck DH, Schenk M, Doepfmer U, Kox WJ. Rectal paracetamol has a significant morphine-sparing effect after hysterectomy. Br J Anaesth 2000; 85:658-9. [PMID: 11064632] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
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Schenk M. [DMW (Deutsche Medizinische Wochenschrift) Paul Boerner Prize]. Dtsch Med Wochenschr 2000; 125:A12. [PMID: 11036480] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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100
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Schenk M. [DMW (Deutsche Medizinische Wochenschrift) Walter Siegenthaler Prize]. Dtsch Med Wochenschr 2000; 125:A11. [PMID: 11036479] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
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