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91.
To improve the pharmacokinetic profile of tumor necrosis factor-related apoptosis inducing ligand (TRAIL) an N-terminal specific pegylation was performed to generate pegylated TRAIL (PEG-TRAIL). In in vitro experiments, we found that although PEG-TRAIL was slightly less efficient than recombinant TRAIL in promoting leukemic cell apoptosis, it showed an improved ability to promote migration of bone-marrow mesenchymal stem cells and to elicit the ERK1/2 intracellular signal transduction pathway. Overall, these data suggest that TRAIL pegylation retains, or even enhances, the biological activities of TRAIL relevant for its therapeutic applications.  相似文献   
92.
Selective targeted delivery of TNFalpha to tumor blood vessels   总被引:4,自引:0,他引:4       下载免费PDF全文
We sought to enhance the selective toxicity of tumor necrosis factor alpha (TNFalpha) to permit its systemic use in cancer therapy. Because ligand-targeted therapeutics have proven successful in improving the selective toxicity of drugs, we prepared a fusion protein (L19mTNFalpha) composed of mouse TNFalpha and a high-affinity antibody fragment (L19 scFv) to the extradomain B (ED-B) domain of fibronectin, a marker of angiogenesis. L19mTNFalpha was expressed in mammalian cells, purified, and characterized. L19mTNFalpha was an immunoreactive and biologically active homotrimer. Radiolabeled L19mTNFalpha selectively targeted tumor neovasculature in tumor-bearing mice, where it accumulated selectively and persistently (tumor-to-blood ratio of the percentage of injected dose per gram [%ID/g] of 700, 48 hours from injection). L19mTNFalpha showed a greater anticancer therapeutic activity than both mTNFalpha and TN11mTNFalpha, a control fusion protein in which an antibody fragment, irrelevant in the tumor model used, substituted for L19. This activity was further dramatically enhanced by its combination with melphalan or the recently reported fusion protein L19-IL2. In conclusion, L19mTNFalpha allows concentrating therapeutically active doses of TNFalpha at the tumor level, thus opening new possibilities for the systemic use of TNFalpha in cancer therapy.  相似文献   
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During 2011, 5 persons in the area of Lazio, Italy were infected with a monophyletic strain of hepatitis E virus that showed high sequence homology with isolates from swine in China. Detection of this genotype in Italy parallels findings in other countries in Europe, signaling the possible spread of strains new to Western countries.  相似文献   
96.
BACKGROUND: Glomerular filtration rate (GFR) is the best overall index of renal function in health and disease. Inulin and 51Cr-EDTA plasma clearances are considered the gold standard methods for estimating GFR. Unfortunately, these methods require specialized technical personnel over a period of several hours and high costs. In clinical practice, serum creatinine is the most widely used index for the noninvasive assessment of GFR. Despite its specificity, serum creatinine demonstrates an inadequate sensitivity, particularly in the early stages of renal impairment. Recently, cystatin C, a low molecular mass plasma protein freely filtered through the glomerulus and almost completely reabsorbed and catabolized by tubular cells, has been proposed as a new and very sensitive serum marker of changes in GFR. This study was designed to test whether serum cystatin C can replace serum creatinine for the early assessment of nephropathy in patients with type 2 diabetes. METHODS: The study was performed on 52 Caucasian type 2 diabetic patients. Patients with an abnormal albumin excretion rate (AER) were carefully examined to rule out non-diabetic renal diseases by ultrasonography, urine bacteriology, microscopic urine analysis, and kidney biopsy. Serum creatinine, serum cystatin C, AER, serum lipids, and glycosylated hemoglobin (HbA1c) were measured. GFR was estimated by the plasma clearance of 51Cr-EDTA. In addition the Cockcroft and Gault formula (Cockcroft and Gault estimated GFR) was calculated. RESULTS: Cystatin C serum concentration progressively increased as GFR decreased. The overall relationship between the reciprocal cystatin C and GFR was significantly stronger (r = 0.84) than those between serum creatinine and GFR (r = 0.65) and between Cockcroft and Gault estimated GFR and GFR (r = 0.70). As GFR decreased from 120 to 20 mL/min/1.73 m2, cystatin C increased more significantly that serum creatinine, giving a stronger signal in comparison to that of creatinine over the range of the measured GFR. The maximum diagnostic accuracy of serum cystatin C (90%) was significantly better than those of serum creatinine (77%) and Cockcroft and Gault estimated GFR (85%) in discriminating between type 2 diabetic patients with normal GFR (>80 mL/min per 1.73 m2) and those with reduced GFR (<80 mL/min/1.73 m2). In particular, the cystatin C cut-off limit of 0.93 mg/L corresponded to a false-positive rate of 7.7% and to a false-negative rate of 1.9%; the serum creatinine cut-off limit of 87.5 micromol/L corresponded to a false-positive rate of 5.8% and to a false-negative rate of 17.0%. CONCLUSIONS: Cystatin C may be considered as an alternative and more accurate serum marker than serum creatinine or the Cockcroft and Gault estimated GFR in discriminating type 2 diabetic patients with reduced GFR from those with normal GFR.  相似文献   
97.
Background. Native valve endocarditis is frequently managed with antibiotics alone, but prosthetic valve endocarditis usually requires an early operation. What is the best treatment of endocarditis after mitral valve repair?

Methods. From 1986 to 2000, 22 patients were treated for endocarditis affecting a previously repaired mitral valve. Causes of mitral valve dysfunction that led to repair were degenerative (11 patients), ischemic (5 patients), endocarditic (3 patients), rheumatic (2 patients), and functional (1 patient). Endocarditis was active in 21 patients and healed in 1. Interval from initial mitral valve repair to onset of endocarditis ranged from 1 week to 10.3 years (median, 6 months). Pathology included leaflet vegetation (15), annuloplasty vegetation (4), leaflet perforation (5), and abscess (3). Mean follow-up was 3.9 ± 3.3 years.

Results. Fifteen patients underwent repeat mitral valve operations with freedom from mitral valve reoperation of 65%, 41%, and 26% at 30 days, 1 year, and 5 years after onset of endocarditis. After a high early hazard, risk of reoperation fell to 10.8% per year. Seven patients, all with a leaflet vegetation, were treated with antibiotics alone. Antibiotics eradicated infection in all; however all had mitral regurgitation 2+ to 4+. Survival was 96%, 74%, and 68% at 30 days, 1 year, and 5 years. Endocarditis recurred in 1 patient (92% free of event).

Conclusions. Most patients that have endocarditis develop after mitral valve repair require reoperation. However if infection is limited to a leaflet, early reoperation may be unnecessary because antibiotics alone can eradicate infection.  相似文献   

98.
PURPOSE: We characterize the consequences of androgen deprivation therapy on body composition in elderly men. MATERIALS AND METHODS: Using a dual energy x-ray absorptiometry instrument, we determined the changes in bone mineral density, bone mineral content, fat body mass and lean body mass in 35 patients with prostate cancer without bone metastases who received luteinizing hormone releasing hormone analogue for 12 months. RESULTS: At baseline conditions 46% of cases were classified as osteopenic and 14% as osteoporotic at the lumbar spine and 40% were osteopenic and 4% osteoporotic at the hip. Androgen deprivation significantly decreased bone mineral density either at the lumbar spine (mean gm./cm.2 [SD] 1.00 [0.194], 0.986 [0.172] and 0.977 [0.182] at baseline, and 6 and 12 months, respectively, p <0.002) or the hip (0.929 [0.136], 0.926 [0.144] and 0.923 [0.138], p <0.03). A more than 2% decrease in bone mineral density was found at the lumbar spine in 19 men (54.3%) and at the hip in 15 (42.9%). Bone mineral content paralleled the bone mineral density pattern. Lean body mass decreased (mean gm. [SD] 50,287 [6,656], 49,296 [6,554] and 49,327 [6,345], p <0.003), whereas fat body mass consistently increased (18,115 [6,209], 20,724 [6,029] and 21,604 [5,923] p <0.001). CONCLUSIONS: Serial bone densitometry evaluation during androgen deprivation therapy may allow the detection of patients with prostate cancer at risk for osteoporotic fractures, that is those with osteopenia or osteoporosis at baseline and fast bone loss. The change in body composition may predispose patients to accidental falls, thus increasing the risk of bone fracture.  相似文献   
99.

Summary

A total of 507,671 people ≥65 experienced hip fractures between 2000 and 2005. In 2005, 94,471 people ≥65 were hospitalized due to hip fractures, corresponding to a 28.5% increase over 6 years. Most fractures occurred in patients ≥75 (82.9%; n?=?420,890; +16% across 6 years), particularly in women (78.2%; n?=?396,967).

Introduction

We aimed to analyze incidence and costs of hip fractures in Italy over the last 6 years.

Methods

We analyzed the national hospitalization and DRG databases concerning fractures occurred in people ≥65 between 2000 and 2005.

Results

A total of 507,671 people ≥65 experienced hip fractures across 6 years, resulting in about 120,000 deaths. In year 2005 94,471 people aged ≥65 were hospitalized due to hip fractures, corresponding to a 28.5% increase over 6 years. The majority of hip fractures occurred in patients ≥75 (82.9%; n?=?420,890; +16% across 6 years) and particularly in women (78.2%; n?=?396,967). Among women, 84.2% of fractures (n?=?334,223; +28.0% over 6 years) were experienced by patients ≥75, which is known to be the age group with the highest prevalence of osteoporosis, accounting for 68.6% of the overall observed increase in the total number of fractures. Hip fractures in men ≥75 increased by 33.1% (up to 16,540). Hospitalization costs increased across the six examined years (+36.1%) reaching 467 million euros in 2005, while rehabilitation costs rose up to 531 million in the same year.

Conclusions

Hip fractures of the elderly are increasing and represent a major health problem in industrialized countries such as Italy.  相似文献   
100.
Objective To evaluate the prognostic significance of different clinico-pathological and molecular factors, and to compare survival after standard and extended pancreaticoduodenectomy (PD) in ampulla of Vater adenocarcinoma (AVAC). Summary Background Data There are discordant data on factors affecting prognosis, and hence therapeutic choices, in AVAC. Patients and Methods Clinical-pathological factors were evaluated in 59 patients, subjected to PD for AVAC; in 42 subjects information on chromosome 17p and 18q allelic losses (LOH) and microsatellite instability (MSI) was also available. The association between survival and type of PD was investigated in the 25 patients operated between 1990 and 2001 (16 standard and nine extended). Results The overall 5- and 10-year tumor-related survival rates were 46% and 33%, respectively. Sixteen patients had T-stages 1–2, 14 T-stage 3, and 29 T-stage 4 cancers. Chromosome 17p and 18q LOH were detected in 23 (55%) and 15 cases (36%), respectively, and in 12 cases (29%) coexisted. Five cases were MSI-positive (12%). At univariate analysis, poor survival was associated with cancer ulceration (P = 0.051), poor differentiation (P = 0.008), T-stage 4 (P < 0.001), nodal metastases (P = 0.004), chromosome 17p (P < 0.001) and 18q LOH (P = 0.002), and absence of MSI (P = 0.009). At multivariate analysis, only T-stage (P = 0.002) and 17p LOH (P = 0.001) were independent predictors of survival. All patients with MSI-positive cancers were long-survivors (>12 yrs), whereas only 30% of MSI-negative cancer patients survived at 5 years. Extended pancreaticoduodenectomy was associated with a 3-year disease-related survival higher than standard resection (83% vs 31%; P = 0.018). Conclusion MSI and chromosome 17p status allow to better define prognosis within ampullary cancers at the same stage. Surgery alone resulted curative in MSI-positive cancer patients, whereas it was inadequate in patients showing allelic losses, who might benefit from adjuvant therapy. In this observational study, extended PD was associated with increased survival compared to standard procedures. Presented at the 2006 Annual Meeting of the American Hepato-Pancreato-Biliary Association, Miami Beach, Florida, March 9–12, 2006  相似文献   
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