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71.
Häfner HM Bräuer K Eichner M Steins A Möhrle M Blum A Jünger M 《Journal of vascular research》2005,42(1):38-46
Laser Doppler flowmetry (LDF) is frequently used to study the microcirculation. Usually LDF time series are analyzed by conventional linear methods, mainly Fourier analysis. The aim of this study was to observe dynamic blood perfusion of the skin in malignant and benign melanocytic skin lesions. Wavelet transformation was performed on each LDF time series in order to calculate a vasomotion field. First, the differences in vasomotion between healthy and pigmented skin were evaluated visually on six different time scales of the vasomotion field. In order to quantify the findings, vasomotion scale variance (VSV) was calculated for each scale plane of the vasomotion field. These VSV were compared using contrast DeltaVSV to determine the difference between healthy skin and a pigmented skin lesion in the same patient. After the measurements, the skin lesions were excised and examined histologically. We found that wavelet analysis of LDF time series is a specific, sensitive method for the in vivo identification of malignant melanoma. It is a non-invasive procedure and takes minimal time to be carried out. 相似文献
72.
Pınar Eroğlu Esra Erkol İnal Şebnem Özemri Sağ Özlem Görükmez Ali Topak Tahsin Yakut 《Clinical rheumatology》2016,35(5):1245-1251
Oxidative stress was related with carpal tunnel syndrome (CTS). We aimed to clarify the associations between glutathione S-transferase (GST)M1, GSTT1 and GSTP1-Ile105Val polymorphisms and CTS. One hundred-forty patients with CTS and 97 healthy controls were enrolled in this study. Tinel and Phalen signs were noted as positive or negative. Functional and clinical status of patients was evaluated by the Boston Questionnaire. The intensity of hand and/or wrist pain was evaluated on 10 cm visual analog scale (VAS). We applied the polymerase chain reaction (PCR) to determine the polymorphisms of the GSTM1 and GSTT1 and the PCR-restriction fragment length polymorphism method for detecting the GSTP1-Ile105Val polymorphism. The M1 null genotype was significantly higher in patients with CTS compared to healthy controls, and the M1 null genotype seemed to increase the risk of CTS approximately two-fold (P?=?0.011; odds ratio (OR)?=?1.98; 95 % confidence interval (CI) 1.17–3.36). The M1 null, T1 present combined genotype was significantly higher in patients with CTS compared to healthy controls (P?=?0.043); however, it seemed not to increase the risk of CTS (P?=?0.14; OR?=?0.62; 95 % CI 0.33–1.76). We found significantly higher levels of the VAS, Boston Symptom Severity Scale and Phalen sign in patients with the Ile/Val or the Val/Val genotypes compared to those in patients with the Ile/Ile genotype (P?=?0.003, 0.004 and 0.044, respectively). We proposed that genes involved in the protection from oxidative stress may influence the susceptibility, clinical and functional status of CTS. The GSTM1 null genotype may be related with the development of CTS, whereas the Val allele of GSTP1-Ile105Val polymorphism may be associated with worse functional and clinical status in CTS. 相似文献
73.
OBJECTIVES: To determine granulocyte colony-stimulating factor (G-CSF), epithelial neutrophil-activating peptide (ENA)-78, and interleukin (IL)-8 in BAL fluid (BALF), epithelial lining fluid (ELF), and serum for establishing the concentration gradient of G-CSF, ENA-78, and IL-8 between the blood and the alveolar space in ARDS and acute lung injury (ALI); and to evaluate the relationship of G-CSF, IL-8, and ENA-78 to pulmonary neutrophilia and severity of lung injury. DESIGN: Prospective study. SETTING: An adult trauma/surgical ICU. PATIENTS: Nineteen patients with ARDS and 10 patients with ALI. INTERVENTIONS: None. Measurements and main results: BAL and blood sampling simultaneously within 12 h and 24 h after onset of ARDS/ALI; G-CSF was detected in BALF in 18 of 19 patients with ARDS, in 7 of 10 patients with ALI, and in all serum samples. G-CSF in BALF and serum was significantly higher in ARDS than in ALI. ENA-78 was detected in BALF in 14 of 19 patients with ARDS, in 8 of 10 patients with ALI, and in serum of all patients. Levels in BALF and serum were not different between ARDS and ALI. IL-8 was detected in all patients; concentrations in BALF in ARDS were significantly higher than in ALI. Concentrations of G-CSF, ENA-78, and IL-8 in ELF were significantly higher than in serum. G-CSF in BALF and serum and IL-8 in BALF correlated positively with pulmonary neutrophilia. G-CSF in serum and IL-8 in BALF correlated negatively with PaO(2)/fraction of inspired oxygen (FIO(2)) ratio. However, ENA-78 did not show a correlation with neutrophil count or with PaO(2)/FIO(2) ratio. CONCLUSIONS: G-CSF may be pathophysiologically important for accumulation and activation of neutrophils in ARDS. Local G-CSF production is the likely driving force for neutrophils rather than elevation of circulating levels. In comparison to ENA-78, IL-8 seems to be the predominant neutrophil chemoattractant in the early phase of ARDS. 相似文献
74.
Wolfgang Schobersberger Markus Mittermayr Petra Innerhofer Guenther Sumann Beatrix Schobersberger Anton Klingler Markus Simmer Werner Streif Uwe Fischbach Dietmar Fries 《Blood coagulation & fibrinolysis》2004,15(5):419-425
Long-distance travel in a cramped position by aircraft or by bus and car has been suggested to be associated with an increased risk for thromboembolic events. Recently, we demonstrated moderate activation of coagulation after a long-haul flight. At present the single contributing factors (i.e. hypoxia and low humidity on board an aircraft and prolonged sitting in an aircraft, car or bus inducing venous stasis) have not yet been investigated. Therefore we measured markers of coagulation and fibrinolysis as well as functional parameters of coagulation using activated thrombelastography in 19 healthy volunteers before, during and after a real 10-h bus journey. In addition, changes in leg volume were measured. Thrombelastography revealed moderate activation of coagulation in all travelers, which was accompanied by a significant increase in prothrombin fragment F1 + 2. Thrombin-antithrombin III complexes and D-dimer remained unchanged, and tissue-type plasminogen activator and plasminogen-activator inhibitor 1 decreased after travel. After the travel we found a significant increase in leg volume that was exclusively distributed in the calf. We conclude that beside long-haul flights also long-distance bus travel induces a certain activation of the coagulation system. Thus, it is questionable whether hypoxia is the crucial risk factor for thromboembolic events after long-haul flights. 相似文献
75.
Attainment of local drug delivery with paclitaxel-eluting balloon in porcine coronary arteries 总被引:1,自引:0,他引:1
Posa A Hemetsberger R Petnehazy O Petrasi Z Testor M Glogar D Gyöngyösi M 《Coronary artery disease》2008,19(4):243-247
OBJECTIVE: Our purpose was to confirm the local drug delivery of a paclitaxel-eluting balloon by percutaneous intervention of single arterial segments or bifurcations of porcine coronary arteries. METHODS: Eight domestic pigs were subjected to 2 x 30 s Dior balloon dilatation of the mid left anterior descending, left circumflex and proximal right coronary arteries. Bifurcation intervention was performed in six arteries. The dilated, and the distal and proximal reference segments were prepared for tissue paclitaxel concentration measurement. Tissue samples were harvested at mean 1.5, 12, 24 and 48 h after balloon dilatation and plasma samples were taken at various time points. RESULTS: The tissue paclitaxel concentration of the single dilated segment was at 1.5 h postdilatation 1.82+/-1.60 micromol/l, which decreased significantly to 0.73+/-0.27 (P=0.032), 0.62+/-0.34 and 0.44+/-0.31 micromol/l at 12, 24 and 48 h. The bifurcation intervention resulted in 5.10+/-1.80 micromol/l tissue paclitaxel amount in the main branch, which at 12 h had diminished to 1.41+/-1.23 micromol/l (P=0.004). The bifurcation side contained 7.00+/-4.80 micromol/l paclitaxel at 1.5 h postdilatation, which lowered to 2.72+/-0.40 micromol/l (P=0.034). The mean paclitaxel concentration of the reference segments decreased gradually from 0.84+/-0.99 to 0.34+/-0.36 micromol/l (P=0.09), 0.28+/-0.16 and 0.19+/-0.18 micromol/l tissue at 1.5, 12, 24 and 48 h postdilatation, respectively. No paclitaxel was found in the peripheral blood at any time point. CONCLUSION: Short exposure of the coronary artery to paclitaxel with a coated balloon is sufficient for the attainment of an adequate tissue concentration of paclitaxel, which is known to be efficient in inhibiting neointimal growth. 相似文献
76.
Lauterbach M Horstick G Plum N Heimann A Becker D Weilemann LS Münzel T Kempski O 《Clinical hemorheology and microcirculation》2005,32(1):1-12
We evaluated late (4 hrs) effects of reperfusion on hemodynamics after 30 or 60 min occlusion of the superior mesenteric artery (SMA) in a rat model. Spontaneously breathing animals (n=30) underwent occlusion of the SMA for 0 (sham), 30 (SMAO_30) or 60 min (SMAO_60) followed by reperfusion with normal saline. Abdominal blood flow (ABF), SMA blood flow (SBF), arterial blood pressure and heart rate were recorded continuously. Systemic vascular resistance (SVR) and SMA vascular resistance (MVR) were calculated at baseline and after 240 min reperfusion (240R). All animals survived in SMAO_30 and sham, two died in SMAO_60 after 120R. ABF remained constant in all groups. SVR increased in SMAO_30 and sham and decreased in SMAO_60 at 240R. SBF was significantly lower after reperfusion in ischemia groups as compared to sham. After 120R, SBF had increased significantly in SMAO_60 versus SMAO_30. MVR increased significantly in SMAO_30 but not in SMAO_60 and sham at 240R. 60 minutes SMA occlusion revealed early hemodynamic changes of septic circulation with increased blood flow in the SMA, decreased SVR, and pseudo-normalization of MVR. Prolonged observation periods are required to detect these significant changes which are overlooked when only studying 120 minutes of reperfusion as usually done. 相似文献
77.
Preethne B?ser Dietmar Seemann Michael J. Liguori Leimin Fan Lili Huang Mathias Hafner Andreas Popp Bernhard K. Mueller 《The AAPS journal》2015,17(4):930-938
High levels of hepcidin, the main regulator of systemic iron metabolism, lead to various diseases. Targeting hepcidin and lowering its concentration is a possible form of intervention in order to treat these diseases. High turnover rate of hepcidin is a major drawback of therapies directly targeting this peptide. We developed two monoclonal antibodies ABT-207 and h5F9-AM8 which inhibit hemojuvelin/repulsive guidance molecule C (RGMc) and downregulate hepcidin. We conducted single-application and dose response studies to understand the antibodies’ mechanism and subchronic toxicology studies to exclude safety-related concerns. Investigation was carried out at different biological levels through qPCR, Affymetrix, liquid chromatography coupled with mass spectrometry (LC-MS/MS), histopathology, serum iron, unsaturated iron binding capacity (UIBC), and drug concentration measurements. After a single application of these antibodies, hepcidin expression in liver and its serum protein levels were reduced. Serum iron increased for several weeks. The RGMc antibodies show a pronounced dose response relationship in rats with h5F9-AM8 having an IC50 (UIBC) of approximately 80-fold higher than ABT-207. When hepcidin levels were downregulated, iron deposition in the liver was visible histologically 1 week post application. These antibody-mediated iron depositions were not associated with any adverse toxicologically relevant effect at the doses and time points evaluated. Iron depositions seen after 14 weekly treatments with ABT-207 were reversible in rats and in cynomolgus monkeys. Due to their long-lasting effects and excellent safety profile, both RGMc-blocking antibodies ABT-207 and h5F9-AM8 are favorable clinical candidates for diseases characterized by high serum hepcidin levels like anemia of chronic disease.
Electronic supplementary material
The online version of this article (doi:10.1208/s12248-015-9770-4) contains supplementary material, which is available to authorized users.KEY WORDS: ABT-207, h5F9-AM8, hepcidin, PK/PD analysis, safety assessment 相似文献78.
Marcus Bahra Dietmar Jacob Jan M. Langrehr Ulf P. Neumann Peter Neuhaus 《Journal of hepato-biliary-pancreatic sciences》2008,15(5):501-507
Background/Purpose
Carcinoma of the distal bile duct is associated with poor prognosis. Surgical resection remains the only potentially curative treatment. We conducted a retrospective study to identify prognostic factors determining longterm survival.Methods
From 1990 to 2006, 95 patients with distal and/or middle bile duct carcinoma had resections. Fifty-four patients underwent pylorus-preserving pancreaticoduodenectomy (57%) and 41 patients underwent standard Kausch-Whipple pancreaticoduodenectomy (43%). Nine patients underwent pancreaticoduodenectomy including portal vein resection (9%).Results
Overall 1-, 3-, and 5-year survival rates were 60%, 36%, and 29%, respectively. Five-year survival after R0 resection was 34%, and after R1 resection it was 0%. Four patients died during their hospital stay (4%). Multivariate analysis showed negative resection margins (P = 0.040), lymphatic vessel invasion (P = 0.036), and portal vein infiltration (P = 0.027) as strong predictors for survival, whereas the location of the tumor (distal bile duct vs middle bile duct) and lymph node status were not identified as independent prognostic factors.Conclusions
Five-year survival depends strongly on negative resection margins, independent of nodal status. Portal vein resections in patients with portal vein involvement fail to ameliorate long-term survival. Primary tumor site — middle bile duct or distal bile duct — did not determine prognosis.79.
Evidence that thrombocytopenia observed in humans treated with orally bioavailable glycoprotein IIb/IIIa antagonists is immune mediated 总被引:3,自引:0,他引:3
Billheimer JT Dicker IB Wynn R Bradley JD Cromley DA Godonis HE Grimminger LC He B Kieras CJ Pedicord DL Spitz SM Thomas BE Zolotarjova NI Gorko MA Hollis GF Daly RN Stern AM Seiffert D 《Blood》2002,99(10):3540-3546
Glycoprotein (GP) IIb/IIIa antagonists are effective therapeutic agents, but elicit thrombocytopenia with a frequency that approaches 2%. Here, we provide evidence that thrombocytopenia in humans treated with the GP IIb/IIIa antagonist roxifiban is immune mediated. Two patients underwent conversion to a highly positive drug-dependent antibody (DDAB) status temporally associated with thrombocytopenia. Despite the continued presence of DDABs, the fall in platelet count was reversed by discontinuation of drug treatment, pointing to the exquisite drug dependency of the immune response. DDABs appear to bind to neoepitopes in GP IIb/IIIa elicited on antagonist binding. This information was used to develop an enzyme-linked immunosorbent assay (ELISA) for DDAB using solid-phase GP IIb/IIIa. A high level of specificity is indicated by the observation that DDAB binding is dependent on the chemical structure of the GP IIb/IIIa antagonist and that only 2% to 5% of human blood donors and 5% of chimpanzees present with pre-existing DDABs. Furthermore, none of 108 nonthrombocytopenic patients from the phase II roxifiban study showed an increase in antibody titer. Absorption of thrombocytopenia plasma with platelets reduced the DDAB ELISA signal, indicating that the test detects physiologically relevant antibodies. Screening patients for pre-existing or increasing DDAB titer during treatment with GP IIb/IIIa antagonists may reduce the incidence of drug-induced thrombocytopenia. 相似文献
80.
Pilecky David Duray Gabor Z. Elsner Dietmar Israel Carsten W. Erath-Honold Julia W. Vamos Mate 《Heart failure reviews》2022,27(6):2165-2176
Heart Failure Reviews - Cardiac resynchronization therapy (CRT) may improve not only impaired left ventricular contractility but can also induce reverse remodeling of native conduction system.... 相似文献