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101.
102.
Delayed massive hemorrhage after pancreatic and biliary surgery: embolization or surgery? 总被引:12,自引:0,他引:12
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de Castro SM Kuhlmann KF Busch OR van Delden OM Laméris JS van Gulik TM Obertop H Gouma DJ 《Annals of surgery》2005,241(1):85-91
OBJECTIVE: To analyze the management of delayed massive hemorrhage (DMH) after major pancreatic and biliary surgery. SUMMARY BACKGROUND DATA: Despite a decreased mortality rate for pancreatic and biliary surgery, DMH is still an important cause of postoperative mortality. The aim of the present study was to analyze the management of DMH after pancreatic and biliary surgery, and specifically to assess the role of embolization and surgical intervention. METHODS: The study group (SG) consisted of 1010 patients from 1994 to 2002 who underwent pancreatic or biliary surgery (cholecystectomy excluded). Patients from a previous study (1983-1993, n = 686) were used as a historical control group (HCG). RESULTS: The incidence of DMH (SG 2.3% vs. HCG 3.2%) declined somewhat but did not differ significantly between both periods. The number of patients with a septic complication (SG 74% vs. HCG 50%) and a sentinel bleed (SG 78% vs. HCG 100%) before the onset of DMH did not differ significantly. Embolization (SG 2 of 2 patients vs. HCG 0 of 2 patients) was not used frequently. Successful outcome after surgical intervention (SG 14 of 16 patients vs. HCG 8 of 14 patients) and the surgical procedures performed to obtain hemostasis were comparable and overall mortality (SG 22% vs. HCG 29%) was comparable. CONCLUSIONS: The incidence of DMH declined somewhat from 3.2% to 2.3% over the past years. Most patients present with septic complications and a sentinel bleed before onset of DMH. Despite general acceptance of embolization in our unit, it was used infrequently in patients with DMH. Aggressive surgical intervention was the treatment of choice in patients with DMH after pancreatic or biliary surgery. 相似文献
103.
Dose-dependent activation of Ca2+-activated K+ channels by ethanol contributes to improved endothelial cell functions 总被引:1,自引:0,他引:1
Kuhlmann CR Li F Lüdders DW Schaefer CA Most AK Backenköhler U Neumann T Tillmanns H Waldecker B Erdogan A Wiecha J 《Alcoholism, clinical and experimental research》2004,28(7):1005-1011
BACKGROUND: Regular moderate alcohol (EtOH) intake seems to protect against both coronary artery disease and ischemic stroke, whereas the risk increases with heavy EtOH consumption. Effects of EtOH on endothelial cell function may be relevant to these disparate effects. Potassium channels play an important role in the regulation of endothelial cell functions. Therefore, we investigated whether Ca-activated K channels (BKCa) are modulated by EtOH. Furthermore, we examined whether EtOH-induced changes of endothelial nitric oxide (NO) formation and cell proliferation are due to BKCa activation. METHODS: The patch-clamp technique was used to investigate BKCa activity in cultured human umbilical vein endothelial cells (HUVEC). NO formation was analyzed by using the fluorescence dye 4,5-diaminofluorescein. Endothelial proliferation was examined by using cell counts and measuring [H]thymidine incorporation. RESULTS: EtOH dose-dependently (10-150 mmol/liter) modulated BKCa-activity, with the highest increase of open-state probability at a concentration of 50 mmol/liter (n = 13; p < 0.05). Inside-out recordings revealed that this effect was due to direct BKCa activation, whereas open-state probability was not changed in cell-attached recordings after pertussis toxin preincubation. EtOH (10 and 50 mmol/liter) caused a significant increase of NO levels, which was blocked by the highly selective BKCa inhibitor iberiotoxin (100 nmol/l; n = 30; p < 0.05). Higher concentrations of EtOH (100 and 150 mmol/liter) significantly reduced NO synthesis (n = 30; p < 0.05). Both methods revealed a significant increase of HUVEC proliferation, which was inhibited by iberiotoxin (n = 30; p < 0.05). At a concentration of 150 mmol/liter, EtOH caused a significant reduction of endothelial proliferation. CONCLUSIONS: EtOH directly activates BKCa in HUVEC, leading to an increase of endothelial proliferation and production of NO. These results indicate a possible beneficial effect of low-dose EtOH on endothelial function, whereas higher concentrations must be considered as harmful. 相似文献
104.
105.
Surgical palliation in pancreatic cancer 总被引:2,自引:0,他引:2
The prognosis of patients with pancreatic carcinoma is poor. At the time of diagnosis, approximately 80% of patients are found to have an unresectable tumour, because of local spread or metastatic disease. Therefore, most patients will undergo palliative treatment, which is aimed at the improvement of the quality of life and the prevention of symptoms. The most important symptoms which are associated with advanced pancreatic cancer are pain, obstructive jaundice and gastric outlet obstruction. Controversy remains on the question whether these symptoms should be treated surgically or non-surgically. This review describes the best evidence (if possible randomised controlled trials) in recent literature on the palliation of most important symptoms and focuses on surgical palliative treatment options. 相似文献
106.
Neumann-Haefelin C Beha A Kuhlmann J Belz U Gerl M Quint M Biemer-Daub G Broenstrup M Stein M Kleinschmidt E Schaefer HL Schmoll D Kramer W Juretschke HP Herling AW 《Diabetes》2004,53(3):528-534
The physiological dynamics of intramyocellular lipids (IMCLs) in different muscle types and of hepatocellular lipids (HepCLs) are still uncertain. The dynamics of IMCLs in the soleus, tibialis anterior, and extensor digitorum longus (EDL) muscles and HepCL during fed, 12- to 72-h starved, and refed conditions were measured in vivo by (1)H-magnetic resonance spectroscopy (MRS) in Wistar rats. Despite significant elevations of free fatty acids (FFAs) during starvation, HepCLs and IMCLs in soleus remained constant. In tibialis anterior and EDL, however, IMCLs increased significantly by 170 and 450% after 72 h of starvation, respectively. After refeeding, elevated IMCLs dropped immediately in both muscles. Total muscle long-chain acyl-CoAs (LCACoAs) remained constant during the study period. Hepatic palmitoleoyl-CoA (C16:1) decreased significantly during starvation while total hepatic LCACoAs increased significantly. Consistent with constant values for FFAs, HepCLs, IMCLs, and muscle LCACoAs from 12-72 h of starvation, insulin sensitivity did not change. We conclude that during starvation-induced adipocytic lipolysis, oxidative muscles dispose elevated FFAs by oxidation, while nonoxidative ones neutralize FFAs by reesterification. Both mechanisms might prevent impairment of insulin signaling by maintaining low levels of LCACoAs. Hepatic palmitoleoyl-CoA might have a special role in lipid metabolism due to its unique dynamic profile during starvation. 相似文献
107.
Kuhlmann CR Gast C Li F Schäfer M Tillmanns H Waldecker B Wiecha J 《Journal of the American Society of Nephrology : JASN》2004,15(4):868-875
Statins are known to counteract the process of arteriosclerosis by exerting direct pleiotropic effects on vascular endothelium. The aim of this study was to investigate a possible effect of cerivastatin on endothelial Ca(2+)-activated K+ channels (BK(Ca)) and to assess their contribution to cerivastatin-mediated changes of endothelial nitric oxide (NO) production and proliferation. Membrane potential was measured using bis-1,3-dibutylbarbituric acid-trimethine oxonol-fluorescence imaging. Patch-clamp recordings of BK(Ca) were performed on cultured human umbilical vein endothelial cells. NO production was measured using 4,5-diaminofluorescein-fluorescence imaging and a [(3)H]cGMP RIA. Proliferation was analyzed by means of cell counts and [(3)H]thymidine incorporation (TI). Cerivastatin (0.001 to 0.05 micromol/L) caused a significant membrane hyperpolarization (n = 30; P < 0.05). This effect was abolished using the BK(Ca) inhibitor iberiotoxin (IBX; 100 nmol/L). The addition of mevalonate (500 micromol/L) blocked the BK(Ca) activation induced by cerivastatin (n = 19; P < 0.05). Endothelial cGMP level was increased by acetylcholine (ACh; 1 micromol/L). The combination of ACh and cerivastatin additionally increased cGMP levels, with a maximum at 0.03 micromol/L cerivastatin (84%; n = 10, P < 0.01). ACh-induced increase of cGMP-level was significantly reduced by IBX (n = 10, P < 0.01) as it was with all combined administrations of ACh and cerivastatin. 4,5-Diaminofluorescein-fluorescence measurements revealed a significant increase of NO levels by cerivastatin, which was abolished by IBX (n = 30; P < 0.05). Cell counts and TI demonstrated significant inhibition of human umbilical vein endothelial cell proliferation with a maximum at 0.03 micro mol/L (cell count, -32.2%; TI, -70%; n = 12; P < 0.01). These data show that cerivastatin activates endothelial BK(Ca), which plays an important role in the signaling of cerivastatin-mediated endothelial NO production and proliferation. 相似文献
108.
Tumoral calcinosis is characterised by deposits of hydroxyapatite in the soft tissues. The authors report an observation of localization at the level the P.I.P. joint of a ring finger. The lesion appeared to be a subcutaneous tumour but had completely eroded the distal epiphysis of the middle phalanx. The diagnosis was made radiographically and was confirmed by histology. Calcinosis presents in two very different forms; either disseminated or localised. The localised form can invade the juxta-articular gliding spaces. It may exhibit one of two clinical courses: one is acute and diffuse. The other is chronic, localised and insidious and gives rise to tumoral masses arising near joints, but without invading them. An erosive tumoral calcinosis is exceptional. It is characterized by bony right up to the articular surfaces. At the level of the wrist and the hand, tumoral forms are rare and we could only find one other case in the literature and it was localized in the middle finger. 相似文献
109.
Schaefer CA Kuhlmann CR Gast C Weiterer S Li F Most AK Neumann T Backenköhler U Tillmanns H Waldecker B Wiecha J Erdogan A 《Vascular pharmacology》2004,41(2):67-73
The proliferation of endothelial cells is induced by oxidized low-density lipoprotein (oxLDL) and its major component, lysophosphatidylcholine (LPC). The aim of this study was to investigate the effect of statins on the proliferation of endothelial cells derived from human umbilical cord veins (HUVEC). Cerivastatin, simvastatin and fluvastatin caused a dose-dependent inhibition of endothelial cell growth (n=12; P<.01) when using cell counts and [3H]-thymidine incorporation, respectively. The strongest inhibition of HUVEC proliferation was achieved at statin concentrations of 0.1 micromol/l (cerivastatin), 2.5 micromol/l (simvastatin) and 1 micromol/l (fluvastatin). Cell counts were significantly reduced from 22937+/-280.6 (control) to 7791+/-133.6 (cerivastatin), 7292+/-146.6 (simvastatin) and 6792+/-135.5 (fluvastatin) (n=12; P<.01). Interestingly, cell proliferation induced by oxLDL (10 microg/ml) and LPC (20 micromol/l) could be effectively prevented using statins at concentrations between 0.01 and 0.1 micromol/l (cerivastatin), 1 and 2.5 micromol/l (simvastatin) and 0.25 and 1 micromol/l (fluvastatin). This effect of the statins was abolished by preincubation with mevalonate (500 micromol/l). Our results demonstrate an interesting direct effect of statins on the proliferation of human endothelial cells induced by oxLDL and LPC, which may be beneficial to prevent vascular effects of these atherogenic lipids. 相似文献
110.
Early age of onset in fatal familial insomnia 总被引:2,自引:0,他引:2
Harder A Gregor A Wirth T Kreuz F Schulz-Schaeffer WJ Windl O Plotkin M Amthauer H Neukirch K Kretzschmar HA Kuhlmann T Braas R Hahne HH Jendroska K 《Journal of neurology》2004,251(6):715-724
Abstract.
Fatal familial insomnia (FFI) is a prion disease exhibiting the PRNP D178N/129M genotype. Features of this autosomal dominant illness are progressive insomnia, dysautonomia, myoclonus, cognitive decline and motor signs associated with thalamic nerve cell loss and gliosis. In contrast to the new variant of Creutzfeldt-Jakob disease (vCJD) the onset of FFI is in middle to late adulthood. We report two male patients who belong to a large German FFI kindred. They were examined clinically, and postmortem neuropathological examination was carried out in collaboration with the German reference centre for prion disease. Additionally, the prion protein gene (PRNP) was analysed. To identify further patients with disease onset under 30 years of age a comprehensive literature review was carried out. Two male patients presented with typical symptoms of FFI at the age of 23 and 24 years. In their kindred, the age of onset has never before been under 44 years of age. Our literature review identified five additional early onset cases who died at age 21 to 25 years. In all 22 reviewed FFI families the median manifestation age was 49.5 years. Although phenotypic variability of FFI is common, age of onset under 30 years has been considered to be a hallmark of vCJD with a mean manifestation at 27 years of age. Our findings underline that in addition to vCJD, FFI must be considered in cases of young-onset prion disease. This has considerable impact on clinical management and genetic counselling.* These two authors contributed equally 相似文献