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51.
Electrochemical lesions in the rat liver support its potential for treatment of liver tumors 总被引:1,自引:0,他引:1
Wemyss-Holden SA Robertson GS Dennison AR de la M Hall P Fothergill JC Jones B Maddern GJ 《The Journal of surgical research》2000,93(1):55-62
BACKGROUND: An effective therapy is needed for patients with surgically unresectable liver tumors who have very limited life expectancy. One possible treatment is electrochemical tumor necrosis. This study investigated the natural history of electrochemical lesions in the normal rat liver. MATERIALS AND METHODS: A direct current generator, connected to platinum electrodes, was used to create controlled areas of liver necrosis. Animals were sacrificed 2 days, 2 weeks, 2 months, and 6 months after treatment and the macroscopic and histological appearance of the necrotic lesions was followed. RESULTS: No animal died as a result of electrolysis; postoperatively, all gained weight normally. Liver enzymes were significantly (P < 0.001) elevated after treatment, but returned to normal after a week. Two days after electrolysis, histology confirmed an ellipsoidal area of coagulative necrosis at the site of the electrode tip and commonly a segment of peripheral necrosis. After 2 weeks there was histological evidence of healing. By 6 months, very little necrotic tissue remained within a small fibrous scar. CONCLUSIONS: Electrolysis is a safe method for creating defined areas of liver necrosis that heal well with no associated mortality. This study supports the potential of electrolysis for treating patients with unresectable liver tumors. 相似文献
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Carmen Hoh David Boocock Tim Marczylo Rajinder Singh David P Berry Ashley R Dennison David Hemingway Andrew Miller Kevin West Stephanie Euden Giuseppe Garcea Peter B Farmer William P Steward Andreas J Gescher 《Clinical cancer research》2006,12(9):2944-2950
Silibinin, a flavonolignan from milk thistle, has intestinal cancer chemopreventive efficacy in rodents. It is a strong antioxidant and modulates the insulin-like growth factor (IGF) system by increasing circulating levels of IGF-binding protein 3 (IGFBP-3) and decreasing levels of IGF-I. Here, the hypothesis was tested that administration of oral silibinin generates agent levels in human blood and colorectal and hepatic tissues consistent with pharmacologic activity. Patients with confirmed colorectal adenocarcinoma received silibinin formulated with phosphatidylcholine (silipide) at dosages of 360, 720, or 1,440 mg silibinin daily for 7 days. Blood and biopsy samples of normal and malignant colorectum or liver were obtained before dosing, and blood and colorectal or hepatic tissues were collected at resection surgery after the final silipide dose. Levels of silibinin were quantified by high-pressure liquid chromatography-UV, and plasma metabolites were identified by liquid chromatography-mass spectrometry. Blood levels of IGFBP-3, IGF-I, and the oxidative DNA damage pyrimidopurinone adduct of deoxyguanosine (M1dG) were determined. Repeated administration of silipide was safe and achieved levels of silibinin of 0.3 to 4 micromol/L in the plasma, 0.3 to 2.5 nmol/g tissue in the liver, and 20 to 141 nmol/g tissue in colorectal tissue. Silibinin monoglucuronide, silibinin diglucuronide, silibinin monosulfate, and silibinin glucuronide sulfate were identified in the plasma. Intervention with silipide did not affect circulating levels of IGFBP-3, IGF-I, or M1dG. The high silibinin levels achieved in the human colorectal mucosa after consumption of safe silibinin doses support its further exploration as a potential human colorectal cancer chemopreventive agent. 相似文献
54.
Needham DM Wang W Desai SV Mendez-Tellez PA Dennison CR Sevransky J Shanholtz C Ciesla N Spillman K Pronovost PJ 《Journal of critical care》2007,22(4):275-284
PURPOSE: Long-term follow-up studies in critical care have described survivors' outcomes, but provided less insight into the patient/disease characteristics and intensive care therapies ("exposures") associated with these outcomes. Such insights are essential for improving patients' long-term outcomes. This report describes the development of a strategy for comprehensively measuring relevant exposures for long-term outcomes research, and presents empiric results from its implementation. MATERIALS AND METHODS: A multistep, iterative process was used to develop the exposures strategy. First, a comprehensive list of potential exposures was generated and subsequently reduced based on feasibility, redundancy, and relevance criteria. Next, data abstraction methods were designed and tested. Finally, the strategy was implemented in 150 patients with acute lung injury with iterative refinement. RESULTS: The strategy resulted in the development of more than 60 unique exposures requiring less than 45 minutes per patient-day for data collection. Most exposures had minimal missing data and adequate reliability. These data revealed that evidence-based practices including lower tidal volume ventilation, spontaneous breathing trials, sedation interruption, adequate nutrition, and blood glucose of less than 6.1 mmol/L (110 mg/dL) occurred in only 23% to 50% of assessments. CONCLUSIONS: Using a multistep, iterative process, a comprehensive and feasible exposure measurement strategy for long-term outcomes research was successfully developed and implemented. 相似文献
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Dennison EM Compston JE Flahive J Siris ES Gehlbach SH Adachi JD Boonen S Chapurlat R Díez-Pérez A Anderson FA Hooven FH LaCroix AZ Lindsay R Netelenbos JC Pfeilschifter J Rossini M Roux C Saag KG Sambrook P Silverman S Watts NB Greenspan SL Premaor M Cooper C;GLOW Investigators 《BONE》2012,50(6):1288-1293
IntroductionGreater awareness of the relationship between co-morbidities and fracture risk may improve fracture-prediction algorithms such as FRAX.Materials and methodsWe used a large, multinational cohort study (GLOW) to investigate the effect of co-morbidities on fracture risk. Women completed a baseline questionnaire detailing past medical history, including co-morbidity history and fracture. They were re-contacted annually to determine incident clinical fractures. A co-morbidity index, defined as number of baseline co-morbidities, was derived. The effect of adding the co-morbidity index to FRAX risk factors on fracture prevention was examined using chi-squared tests, the May–Hosmer test, c index and comparison of predicted versus observed fracture rates.ResultsOf 52,960 women with follow-up data, enrolled between October 2006 and February 2008, 3224 (6.1%) sustained an incident fracture over 2 years. All recorded co-morbidities were significantly associated with fracture, except for high cholesterol, hypertension, celiac disease, and cancer. The strongest association was seen with Parkinson's disease (age-adjusted hazard ratio [HR]: 2.2; 95% CI: 1.6–3.1; P < 0.001). Co-morbidities that contributed most to fracture prediction in a Cox regression model with FRAX risk factors as additional predictors were: Parkinson's disease, multiple sclerosis, chronic obstructive pulmonary disease, osteoarthritis, and heart disease.ConclusionCo-morbidities, as captured in a co-morbidity index, contributed significantly to fracture risk in this study population. Parkinson's disease carried a particularly high risk of fracture; and increasing co-morbidity index was associated with increasing fracture risk. Addition of co-morbidity index to FRAX risk factors improved fracture prediction. 相似文献
57.
In vitro evaluation of prothrombin complex concentrates in a thrombin generation assay, using DAPA and purified components of the prothrombinase complex, demonstrated significant levels of coagulant- active "phospholipid replacing" activity. Quantification of this activity showed a significant correlation (r = 0.8747, p less than 0.01) with thrombogenicity measured in vivo in a stasis model in rabbits. Extracted lipid material retained full phospholipid replacing activity in the vitro assay. Thin-layer chromatographic characterization confirmed the presence of phospholipids with known coagulant activity in vitro. In vivo, the extracted material was nonthrombogenic but augmented the thrombogenicity of purified factor Xa. Substitution of a synthetic coagulant-active phospholipid (phosphatidylcholine-phosphatidylserine lipid vesicles) for the extracted phospholipid produced a similar augmentation of a factor-Xa- induced thrombogenicity in vivo. It is concluded that the coagulant- active phospholipid content of prothrombin complex concentrates is a major determinant of thrombogenicity but requires the presence of activated clotting factors for its expression in vivo. 相似文献
58.
Sayer AA Syddall HE Gilbody HJ Dennison EM Cooper C 《The journals of gerontology. Series A, Biological sciences and medical sciences》2004,59(9):M930-M934
BACKGROUND: Sarcopenia is defined as the loss of skeletal muscle mass and strength with aging. Recent epidemiological studies have shown that men and women who grew less well in early life have lower muscle strength. Our objective was to investigate the relationship between birth weight, infant growth, and the development of sarcopenia. METHODS: We studied 730 men and 673 women, of known birth weight and weight at 1 year, who were born in Hertfordshire, U.K., between 1931 and 1939. Participants completed a health questionnaire, and we measured their height, weight, and grip strength. Standard deviation scores for birth weight, and for infant growth conditional on birth weight, were analyzed in relation to grip strength before and after adjustment for adult size. RESULTS: Grip strength was most strongly associated with birth weight in men (r = 0.19, p < .001) and women (r = 0.16, p < .001). These relationships remained significant after adjustment for adult height and weight. In contrast, the associations with infant growth were weakened after allowing for adult size. Adjustment for age, current social class, physical activity, smoking, and alcohol did not affect these results. CONCLUSIONS: Birth weight is associated with sarcopenia in men and women, independently of adult height and weight. The influence of infant growth on long-term muscle strength appears to be mediated through adult size. Sarcopenia may have its origins in early life, and identifying influences operating across the whole life course may yield considerable advances in developing effective interventions. 相似文献
59.
Dammacco F; Sansonno D; Han JH; Shyamala V; Cornacchiulo V; Iacobelli AR; Lauletta G; Rizzi R 《Blood》1994,84(10):3336-3343
Type II mixed cryoglobulinemia (MC) is an often progressive vasculitis characterized by circulating cold-precipitable proteins that usually consists of polyclonal IgG and monoclonal IgM kappa with rheumatoid factor (RF) activity. Its etiology is unknown, although recent evidence strongly suggests that hepatitis C virus (HCV) plays a major role. Plasmapheresis, corticosteroids, and cytotoxic drugs have been used in the therapy of MC patients. Recently, favorable results with recombinant interferon-alpha (rIFN alpha) have been reported. To further assess its effectiveness, we studied the effects of natural human interferon-alpha (nIFN alpha), alone and in combination with 6- methyl-prednisolone (PDN), in a prospective, randomized, controlled trial in patients with symptomatic MC. Sixty-five patients were enrolled onto the trial, 52 (80%) of whom presented serum anti-HCV antibodies and specific genomic RNA sequences. Fifteen patients received nIFN alpha (3 MU) intramuscularly (IM) three times weekly, whereas 17 patients also received 16 mg/d of PDN orally on non-IFN days. Moreover, 18 patients received 16 mg/d of PDN only, and 15 were untreated. Treatment was discontinued after 1 year and patients were monitored for 8 to 17 months (mean, 13). A complete response was achieved in eight of 15 patients (53.3%) treated with nIFN alpha and nine of 17 (52.9%) treated with nIFN alpha plus PDN, as compared with three of 18 patients (16.7%) who received PDN only (P < .05) and one of 15 (6.7%) untreated controls (P < .01). Partial response occurred in two of 15 (13.3%) patients treated with nIFN alpha, three of 17 (17.6%) who received nIFN alpha plus PDN, one of 18 (5.5%) who received PDN only, and one of 15 (6.7%) controls. A complete response in six patients (66.7%) was achieved within 3 months in the group that received nIFN alpha plus PDN, as compared with two patients (25%) of those who received nIFN alpha alone (P < .02). In anti-HCV-positive patients, the clinical response occurred in step with reduced or undetectable levels of HCV RNA and transaminase normalization. Quantification of circulating HCV RNA represented a good predictive response marker. The probability of relapse within 3 months after treatment was 100% (three of three patients) and 75% (six of eight patients), respectively, in patients who received PDN alone or nIFN alpha alone as compared with none of those who received nIFN alpha plus PDN (P < .001).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
60.
Experimental myocardial ischemia and infarction Production of diffuse myocardial lesions in unanesthetized calves 总被引:3,自引:0,他引:3
Karl T. Weber MD Theodore I. Malinin MD Benjamin H. Dennison BSEE John M. Fuqua Jr. BS David M. Speaker BSEE Frank W. Hastings MD 《The American journal of cardiology》1972,29(6):793-802
To produce a chronic, ischemic heart failure preparation of controllable severity, plastic microspheres (6 to 14 μ in diameter) were injected into the left main coronary artery of unanesthetized calves. Two dose levels were used (4 and 5 mg/kg, Groups I and II, respectively). Hemodynamic and electrocardiographic changes were not observed during the microsphere infusion. Arterial-coronary sinus lactate differences shifted from positive control values (mean +5.3 mg/ 100 ml) to negative during and throughout the injection (mean −6.4 mg/100 ml). Significant hemodynamic abnormalities at rest (Group II only) were first noted on postinfusion day 1, and unaccompanied by subsequent significant physiologic recovery. These included an increase in left ventricular end-diastolic pressure (+18 to 21 mm Hg), reduction in stroke volume (−32 percent), cardiac output (−25 percent), dP/dt (−22 percent), mean ejection rate (−18 percent) and left ventricular ejection time, and a prolongation of preejection period. Cardiac response to angiotensin-induced stress was impaired in both test groups. Mean heart weight and left ventricular wall thickness increased by 65 and 45 percent, respectively, in both groups. Histopathologic examination demonstrated microinfarcts widely distributed throughout the myocardium supplied by the left coronary artery at various stages of healing, sometimes in the same heart, with typical time-dependent morphologic characteristics. The myocardial fibers were hypertrophied. In addition, atypical areas were found on glycogen selective staining.
The results suggest that the extent of microcirculatory ischemia and infarction determines the degree of myocardial impairment at rest and during stress irrespective of compensatory hypertrophy. 相似文献