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51.
52.
BACKGROUND: The majority of patients with primary or metastatic malignancies confined to the liver are not candidates for resection because of tumor size, location, multifocality, or inadequate functional hepatic reserve. Cryoablation has become a common treatment in select groups of these patients with unresectable liver tumors. However, hepatic cryoablation is associated with significant morbidity. Radiofrequency ablation (RFA) is a technique that destroys liver tumors in situ by localized application of heat to produce coagulative necrosis. In this study, we compared the complication and early local recurrence rates in patients with unresectable malignant liver tumors treated with either cryoablation or RFA. PATIENTS AND METHODS: Patients with hepatic malignancies were entered into two consecutive prospective, nonrandomized trials. The liver tumors were treated intraoperatively with cryoablation or RFA; intraoperative ultrasonography was used to guide placement of cryoprobes or RFA needles. All patients were followed up postoperatively to assess complications, treatment response, and local recurrence of malignant disease. RESULTS: Cryoablation was performed on 88 tumors in 54 patients, and RFA was used to treat 138 tumors in 92 patients. Treatment-related complications, including 1 postoperative death, occurred in 22 of the 54 patients treated with cryoablation (40.7% complication rate). In contrast, there were no treatment-related deaths and only 3 complications after RFA (3.3% complication rate, P<0.001). With a median follow-up of 15 months in both patient groups, tumor has recurred in 3 of 138 lesions treated with RFA (2.2%), versus 12 of 88 tumors treated with cryoablation (13.6%, P<0.01). CONCLUSIONS: RFA is a safe, well-tolerated treatment for patients with unresectable hepatic malignancies. This study indicates that (1) complications occur much less frequently following RFA of liver tumors compared with cryoablation of liver tumors, and (2) early local tumor recurrence is infrequent following RFA.  相似文献   
53.
The aim of this study was to evaluate the accuracy of quantitative 1-day exercise-rest technetium-99m tetrofosmin tomography in the identification of patients with coronary artery disease (CAD) and in the detection of individual stenosed coronary vessels. Sixty-one patients with suspected CAD who underwent coronary angiography and 13 normal volunteers were studied. All patients were submitted to two i.v. injections of99mTc-tetrofosmin, one at peak exercise (370 MBq) and the other (1110 MBq) at rest 3 h after exercise (images 15–30 min after injection for both studies). All patients with CAD (0% luminal stenosis) (n=50) had an abnormal99mTc-tetrofosmin tomogram. Only one patient without significant coronary narrowing showed abnormal findings. Overall sensitivity, specificity and diagnostic accuracy in the detection of individual stenosed vessels were 77%, 93% and 85%, respectively. Sensitivity and diagnostic accuracy in the identification of individuals stenosed coronary vessels were significantly higher (P<0.05) in patients with single-vessel disease (n=21) than in those with multivessel disease (n=29). Sensitivity, specificity and accuracy for detecting individual diseased vessels were similar in patients without previous myocardial infarction (n=26) and in those with previous myocardial infarction (n=35). In myocardial territories related to non-infarcted areas (n=128), sensitivity and specificity in the detection of stenosed vessels were 70% and 95%, respectively. In infarcted areas (n=55), sensitivity and specificity in the detection of stenosed vessels were 85% (P=NS vs non-infarcted areas) and 75% (P<0.05 vs non-infarcted areas), respectively. Finally, sensitivity was significantly lower (P<0.05) in vascular territories supplied by vessels with moderate stenosis (50%–75%) than in those supplied by vessels with severe stenosis (>75%). The results of this study demonstrate that quantitative 1-day exercise-rest99mTc-tetrofosmin single-photon emission tomographic imaging is a suitable and accurate technique to identify patients with CAD and to detect individual stenosed coronary vessels.  相似文献   
54.
Endothelial dysfunction and oxidative stress in chronic renal failure   总被引:6,自引:0,他引:6  
Uremic patients have an increased incidence of cardiovascular disease (CVD), endothelial dysfunction and oxidative stress that can contribute to cardiovascular (CV) events. To assess the relationship between endothelial dysfunction, oxidative stress and renal failure severity, we studied 40 patients (age 57 +/- 7 yrs, 24 males) affected by chronic kidney disease (CKD) K/DOQI stage 3-5 (serum creatinine (Cr) 5.6 +/- 2.2 mg/dL) on conservative treatment, 20 uremic patients (age 57 +/- 12 yrs, 13 males) on hemodialysis (HD) and 30 healthy controls (56 +/- 12 yrs, 20 males). Before and 2 hr after oral vitamin C (2 g) administration, we measured brachial artery endothelium-dependent vasodilation (flow mediated dilation (FMD)) to reactive hyperemia following 5 min of forearm ischemia and the response to sublingual glyceril trinitrate (GTN). Measurements were made by high-resolution ultrasound and computerized analysis. FMD was lower in CKD patients than in controls (5.3 +/- 2.2 vs. 6.9 +/- 2.8%; p<0.01) and was further reduced in HD patients (3.6 +/- 2.7; p<0.01 vs. CKD patients). Response to GTN was similar in all groups. FMD was related to Cr clearance (r=0.42; p<0.01) in CKD patients, while it related inversely to Kt/V(urea) (r=-0.52; p<0.05) in HD patients. After vitamin C administration, FMD was significantly enhanced in HD (4.7 +/- 2.4%; p<0.01 vs. baseline), but not in CKD patients. Response to GTN was unaffected. However, vitamin C load reduced oxidative stress markers, and increased plasma antioxidant capability in both groups. In conclusion, the reduced endothelium-dependent dilation in the brachial artery of CKD patients is related to renal failure severity. HD patients showed a more marked alteration, which seems to be related, at least in part, to increased oxidative stress.  相似文献   
55.
Physical inactivity is associated with alteration of normal physiologic processes leading to muscle atrophy, reduced exercise capacity, insulin resistance, and altered energy balance. Bed rest studies in human beings using stable isotopes of amino acids indicate that muscle unloading decreases the turnover rates of muscle and whole-body proteins, with a prevailing inhibition of protein synthesis. In the fasting state, muscle and whole-body nitrogen loss was not accelerated during bed rest. In experimental postprandial states, the amino acid-mediated stimulation of protein synthesis was impaired, whereas the ability of combined insulin and glucose infusion to decrease whole-body proteolysis was not affected by muscle inactivity. Thus, an impaired ability of protein/amino acid feeding to stimulate body protein synthesis is the major catabolic mechanism for the effect of bed rest on protein metabolism. This suggests that a protein intake level greater than normal could be required to achieve the same postprandial anabolic effect during muscle inactivity. Metabolic adaptation to muscle inactivity also involves development of resistance to the glucoregulatory action of insulin, decreased energy requirements, and increased insulin and leptin secretion. These alterations may lead to the development of the metabolic syndrome that is defined as the association of hyperinsulinemia, dyslipidemia, hypertension, hyperglycemia, and abdominal obesity. This cluster of metabolic abnormalities is a risk factor for coronary artery disease and stroke. Evidence indicates that exercise training programs may counteract all of these abnormalities both in healthy sedentary subjects and in patients affected by a variety of chronic disease states.  相似文献   
56.

Purpose

The aim of this study was to investigate the relationship between 123I-metaiodobenzylguanidine (MIBG) scan semi-quantification and a new 18F-DOPA positron emission tomography (PET)/CT score in patients with suspected or documented neuroblastoma (NB) relapse and to assess the association between these two parameters and progression-free survival (PFS)/overall survival (OS).

Methods

We analysed 24 NB patients who had undergone 123I-MIBG and 18F-DOPA PET/CT scans at the time of suspected relapse, after applying a proper scoring system for each scan. In time-to-event analyses, the score distributions were regarded as continuous and were categorized in tertiles and medians. We used Kaplan-Meier curves and Cox proportional hazard models for PFS and OS in order to estimate the independent prognostic impact of 123I-MIBG and 18F-DOPA PET/CT scans.

Results

The 123I-MIBG and 18F-DOPA scores were highly and positively correlated (Spearman’s rho?=?0.8, p?<?0.001). Over a median follow-up of 14 months (range 6–82), 12 cases of disease progression and 6 deaths occurred. Multivariate Cox models showed a higher risk of disease progression [hazard ratio (HR) 17.0, 95 % confidence interval (CI) 2.7–109] in NB patients with 123I-MIBG score?>?3 (3rd tertile) and an even higher risk (HR:37.2, 95 % CI 2.4–574) in those with 18F-DOPA whole-body metabolic burden (WBMB) >7.5 (median), after adjustment for all main clinical/pathological factors considered. Kaplan-Meier analyses showed a significant association with OS (log-rank p?=?0.01 and p?=?0.03 for 123I-MIBG and 18F-DOPA WBMB, respectively).

Conclusion

Our results confirm the good agreement between 18F-DOPA PET/CT and 123I-MIBG scan in patients affected by NB relapse. In time-to-event analyses, 123I-MIBG scan and 18F-DOPA PET/CT scores were independently and significantly associated with disease progression.  相似文献   
57.
In contrast to traditional approaches to fracture risk assessment using clinical risk factors and bone mineral density (BMD), a new technique, reference point microindentation (RPI), permits direct assessment of bone quality; in vivo tibial RPI measurements appear to discriminate patients with a fragility fracture from controls. However, it is unclear how this relates to the site of the most clinically devastating fracture, the femoral neck, and whether RPI provides information complementary to that from existing assessments. Femoral neck samples were collected at surgery after low‐trauma hip fracture (n = 46; 17 male; aged 83 [interquartile range 77–87] years) and compared, using RPI (Biodent Hfc), with 16 cadaveric control samples, free from bone disease (7 male; aged 65 [IQR 61–74] years). A subset of fracture patients returned for dual‐energy X‐ray absorptiometry (DXA) assessment (Hologic Discovery) and, for the controls, a micro‐computed tomography setup (HMX, Nikon) was used to replicate DXA scans. The indentation depth was greater in femoral neck samples from osteoporotic fracture patients than controls (p < 0.001), which persisted with adjustment for age, sex, body mass index (BMI), and height (p < 0.001) but was site‐dependent, being less pronounced in the inferomedial region. RPI demonstrated good discrimination between fracture and controls using receiver‐operating characteristic (ROC) analyses (area under the curve [AUC] = 0.79 to 0.89), and a model combining RPI to clinical risk factors or BMD performed better than the individual components (AUC = 0.88 to 0.99). In conclusion, RPI at the femoral neck discriminated fracture cases from controls independent of BMD and traditional risk factors but dependent on location. The clinical RPI device may, therefore, supplement risk assessment and requires testing in prospective cohorts and comparison between the clinically accessible tibia and the femoral neck. © 2015 American Society for Bone and Mineral Research.  相似文献   
58.
59.
Osteonecrosis of the femoral head is the endpoint of a disease process that results from insufficient blood flow and bone-tissue necrosis, leading to joint instability, collapse of the femoral head, arthritis of the joint, and total hip replacement. Pain is the most frequent clinical symptom. Both bone tissue and cartilage suffer when osteonecrosis of the femoral head develops. Stimulation with pulsed electromagnetic fields (PEMFs) has been shown to be useful for enhancing bone repair and for exerting a chondroprotective effect on articular cartilage. Two Italian studies on the treatment of avascular necrosis of the femoral head with PEMFs were presented in this review. In the first study, 68 patients suffering from avascular necrosis of the femoral head were treated with PEMFs in combination with core decompression and autologous bone grafts. The second one is a retrospective analysis of the results of treatment with PEMFs of 76 hips in 66 patients with osteonecrosis of the femoral head. In both studies clinical information and diagnostic imaging were collected at the beginning of the treatment and at the time of follow up. Statistical analysis was performed using chi-square test. Both authors hypothesize that the short-term effect of PEMF stimulation may be to protect the articular cartilage from the catabolic effect of inflammation and subchondral bone-marrow edema. The long-term effect of PEMF stimulation may be to promote osteogenic activity at the necrotic area and prevent trabecular fracture and subchondral bone collapse. PEMF stimulation represents an important therapeutic opportunity to resolve the Ficat stage-I or II disease or at least to delay the time until joint replacement becomes necessary.  相似文献   
60.

Purpose

The prognostic value of FDG PET for neuroendocrine tumours (NETs) has been reported. In this study we evaluated the role of FDG PET in predicting response and progression-free survival (PFS) after 177Lu-DOTATATE peptide receptor radionuclide therapy (Lu-PRRT) in patients with advanced well-differentiated grade 1/2 NETs.

Methods

We retrospectively evaluated 52 patients with progressive advanced NETs overexpressing somatostatin receptors and treated with Lu-PRRT with a cumulative activity up to 27.7 GBq divided into five courses. According to WHO 2010/ENETS classification, patients were stratified into two groups: those with grade 1 tumour (Ki-67 index ≤2 %, 19 patients), and those with grade 2 tumour (Ki-67 index >3 % to <20 %, 33 patients). On the basis of the FDG PET scan, 33 patients were classified as PET-positive (PET+) and 19 as PET-negative (PET?).

Results

FDG PET was positive in 57 % of patients with grade 1 NET and in 66 % of patients with grade 2 NET, and the rates of disease control (DC, i.e. complete response + partial response + stable disease) in grade 1 and grade 2 patients were 95 % and 79 %, respectively (P?=?0.232). In PET? and PET+ patients, the DC rates were 100 % and 76 % (P?=?0.020) with a PFS of 32 and 20 months, respectively (P?=?0.033). Of the PET+ patients with grade 1 NET, 91 % showed disease control, whereas about one in three PET+ patients with grade 2 NET (32 %) progressed after Lu-PRRT (DC rate 68 %).

Conclusion

These results suggest that FDG PET evaluation is useful for predicting response to Lu-PRRT in patients with grade 1/2 advanced NETs. Notably, none of PET? patients had progressed at the first follow-up examination after Lu-PRRT. Grade 2 NET and PET+ (arbitrary SUV cutoff >2.5) were frequently associated with more aggressive disease. PET+ patients with grade 2 NET, 32 % of whom did not respond to Lu-PRRT monotherapy, might benefit from more intensive therapy protocols, such as the combination of chemotherapy and PRRT.  相似文献   
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