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41.
The proven antiangiogenic activity of zoledronic acid, a third-generation bisphosphonate widely used in bone metastatic cancer patients, led us to investigate if the vascular endothelial growth factor (VEGF)-related zoledronic acid modifications are correlated with survival advantages in advanced breast cancer patients. Forty-two consecutive breast cancer patients with scintigraphic and radiographic evidence of bone metastases were treated with a single infusion of 4 mg zoledronic acid before anticancer chemotherapy. The patients were prospectively evaluated for circulating levels of VEGF and interferon-gamma (IFN-gamma) just before and at 1, 2, 7, and 21 days after zoledronic acid infusion. Afterward, clinical outcome was prospectively monitored. The basal serum VEGF median levels were significantly decreased at each time point, but the major reduction was recorded 21 days after the infusion. In particular, 25 patients of 42 (59.5%) experienced a reduction of at least 25% in the VEGF circulating levels. In contrast, no statistically significant modifications of the IFN-gamma serum levels were recorded. We stratified patients on the basis of this VEGF reduction 21 days after the infusion. No differences in patient features were recorded between those with or without the VEGF reduction. The analysis of survival showed that patients with a reduction in the VEGF circulating levels had a longer time to first skeletal-related event (p = 0.0002), time to bone progression disease (p = 0.0024), and time to performance status worsening (p = 0.0352) than those without the VEGF reduction. No statistically significant differences were recorded in terms of overall survival and time to visceral progression. This study confirms that zoledronic acid could have an in vivo antiangiogenic property and that the VEGF modifications may represent a surrogate marker able to predict time to first skeletal-related event, time to bone progression disease, and time to worsening of performance status.  相似文献   
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43.
The possible involvement of nitric oxide in the prevention by morphine of apomorphine- and oxytocin-induced penile erection and yawning was investigated by measuring the concentration of NO2- and NO3- in the dialysate obtained with a vertical microdialysis probe implanted in the paraventricular nucleus of the hypothalamus of male rats. Either apomorphine (80 μg/kgs.c.) or oxytocin (30 ng i.c.v.) increased significantly basal NO2- and NO3- concentration in the paraventricular dialysate, penile erection and yawning. Morphine (1, 5 and 10mg/kg i.p.) prevented dose-dependently either apomorphine or oxytocin responses when given 15min before apomorphine or oxytocin. Prevention by morphine of apomorphine and oxytocin responses was abolished by naloxone (3mg/kg i.p.) given 15min before morphine. Morphine prevented apomorphine and oxytocin responses also when given in the lateral ventricles or directly in the paraventricular nucleus. In contrast, the selective agonist of the kappa opioid receptor subtype U-69,593 was found to be ineffective. The present results confirm previous findings showing that morphine acts through μ receptors in the paraventricular nucleus to prevent apomorphine and oxytocin-induced penile erection and yawning and suggest that this morphine effect is mediated by a decreased activity of nitric oxide in the paraventricular nucleus of the hypothalamus. Received: 30 September 1996 / Accepted: 24 January 1997  相似文献   
44.
The current study analyzed the effects of different doses of the calcium channel blocker felodipine on cardiovascular response to a set of standardized laboratory tasks. We randomly allocated 21 essential hypertensive patients to receive extended release felodipine 5 mg, felodipine 10 mg and placebo, each given once daily for 2 weeks, according to a double-blind 3-period design. At the end of each treatment period, patients were examined at resting baseline and while performing a mental arithmetic test, a handgrip test and a cycle ergometry test. Compared to placebo, the average fall in resting blood pressure (BP) was of 7.9 ± 5.6/6.1 ± 4.5 mm Hg with felodipine 5 mg (p < 0.01) and of 15.1 ± 5.8/13.9 ± 4.5 mm Hg with felodipine 10 mg (p < 0.001). During mental arithmetic, BP decrease was 11.6 ± 8.1/9 ± 5 mm Hg with felodipine 5 mg (p < 0.01) and 20.4 ± 8.1/15.3 ± 5 mm Hg with felodipine 10 mg (p < 0.001). During handgrip test, BP was significantly reduced after both felodipine doses by 11.7 ± 9.3/9.5 ± 6.5 mm Hg (p < 0.05) and 22.1 ± 9.3/22.4 ± 6.5 mm Hg (p < 0.001), respectively. During cycle ergometry, systolic BP was significantly reduced after felodipine 10 mg by 20.1 ± 9.4 mm Hg (p < 0.001), whereas the fall induced by felodipine 5 mg (7.7 ± 9.4 mm Hg) was not statistically significant (p > 0.05); diastolic BP was significantly reduced by both felodipine doses [average fall of 6.6 ± 5.8 mm Hg (p < 0.05) after felodipine 5 mg and of 12.7 ± 5.8 mm Hg (p < 0.001) after felodipine 10 mg]. There was no treatment effect on the magnitude of systolic BP reactivity from baseline during either mental arithmetic, handgrip test or cycle ergometry (all, p > 0.05). Heart rate values were significantly higher after both felodipine doses than after placebo, either at rest or during stress testing (all, p < 0.05). These data suggest that felodipine, especially at higher doses, may be effective in lowering BP not only at rest but also during exposure to commonly recurring stressful situations.  相似文献   
45.
46.
The retinoblastoma gene family is composed of three members: the retinoblastoma gene, one of the most studied tumor suppressor genes, and two related genes: p107 and pRb2/p130. These proteins are also known as the pocket proteins due to a unique structural and functional domain composed of subdomains A and B separated by a spacer region that is highly conserved among each of the proteins. These proteins exhibit unique growth suppressive properties that are cell type specific, suggesting that although the pocket proteins may complement each other, they are not fully functionally redundant. With the development of antibodies recognizing these three proteins it is now possible to detect expression in formalin-embedded specimens. Recent studies on 235 lung cancers, using immunohistochemical techniques, suggested an independent role for Rb2/p130 in the development and/or progression of human lung carcinoma. We found a statistically significant inverse relationship between the histological grading (degree of malignant potential) and the expression of pRb/p105, p107 and pRb2/p130 in squamous cell carcinomas, meaning that an increase in grading resulted in a significant decrease in protein expression. This phenomenon was particularly evident for pRb2/p130 (p < .0001) which had the highest percentage of undetectable levels in all the specimens examined and the tightest inverse correlation (p value) with both the histological grading and PCNA expression in the most aggressive tumor types, suggesting an important role for pRb2/p130 in the pathogenesis and progression of certain lung cancers. We further explored the expression of pRb2/p130 protein in routine archival FNAB cytological material from 30 Patients with lung cancer using immunocytochemical techniques, comparing protein expression with tumor type. Two pathologists evaluated the staining pattern and scored the percentage of positive cells. Of the 30 neoplasms, 27 displayed a positive staining for pRb2/p130. In particular, we detected pRb2/p130 in 9 (100%) squamous carcinomas, 11 (84%) adenocarcinomas, 5 (100%) BAC, and 2 (66%) SCC. The percentage of positive nuclei varied in different tumors with the highest expression level in adenocarcinomas. Immunocytochemistry represents a sensitive method for detection of pRb2/p130 expression in cytological or archival specimens, and the level of detection seems to be comparable to paraffin sections. Therefore, this methodology could be used in the preoperative evaluation of routine cytological specimens in order to improve the diagnostic and prognostic evaluation of lung cancer patients.  相似文献   
47.
The occurrence of point mutation alpha-thalassaemia and of complex combinations of haemoglobin defects is underestimated. Haemoglobinopathies, the most frequent monogenic recessive autosomal disorder in man, occur predominantly in Mediterranean, African and Asiatic populations. However, countries of immigration with a low incidence in the indigenous population, are now confronted with a highly heterogeneous array of imported defects. Furthermore, the occurrence of severe phenotypes is bound to increase in the near future because of the endogamous growth of the ethnical minorities and the lack of prevention. We describe an Afghan family in which both partners of a consanguineous relationship are carriers of a beta- as well as an alpha-thalassaemia determinant. The combination of defects was revealed by the in vitro measurement of the beta/alpha biosynthetic ratio and was characterised at the DNA level. The molecular defects involved are the Cd5(-CT), a Mediterranean beta zero-thalassaemia mutation, and the alpha 2(zero/+)-thalassaemia AATA(-AA) polyadenylation defect. The alpha-thalassemia defect is a rare RNA-processing mutant described only twice before in heterozygous form in Asian-Indian patients. The mutation suppresses the expression of a alpha 2 gene and reduces the expression of the less efficient, 3' located alpha 1 gene as well, inducing a near alpha zero-thalassaemia phenotype. This defect is now described for the first time in the homozygous condition in one of the children who, in addition to being homozygous for the alpha-thalassaemia point mutation, is also a carrier of the beta zero-thalassaemia defect. A previously described homozygous case of the alpha (zero/+)-thalassaemia condition, caused by a similar polyadenylation defect, was characterised by a severe HbH disease. However, the patient described here present at 7 years of age with severe caries, like his beta-thalassaemia homozygous brother but without hepatosplenomegaly, haemolysis or severe anaemia. The haematological analysis revealed 9.5 g/dl Hb; 5.4 x 10(12)/I RBC; 0.33 I/I PCV; 61 fl MCV; 17.6 pg MCH and 6.2% of HbA2. The biosynthetic ratio beta:alpha was 1.6 and no HbH fraction was detectable either on electrophoresis or as inclusion bodies. The parents reported no complications during pregnancy, at birth, or in the neonatal period in rural Afghanistan. We presume therefore that the counterbalancing effect induced by the co-existing beta-thalassaemia defect could have modified a potentially severe perinatal HbH disease into a strongly hypochromic but well compensated 'alpha zero-like heterozygous' thalassaemia phenotype. The risk of a severe HbH disease, could have been easily missed in this family which was referred because of a child affected with beta-thalassaemia major.  相似文献   
48.
120 patients with progressive systemic sclerosis (PSS) were studied and subdivided into five groups according to the PSS classification of Giordano et al. ("acute diffuse scleroderma", "intermediate syndrome", "acrosclerosis sensu stricto", "sclerodactylia" and "sclerosis sine scleroderma"). In all five subgroups telangiectasias incidence was high (from 75% to 100%). The "ramosus" and "telangiectatic mats" types occur more frequently than other forms of telangiectasias. The former particularly involves the face, neck and chest; whereas the latter more usually involves the upper extremities and is the only type which appears at the lips. Cuticular telangiectasia is a third type, as important as the others but less frequent. The incidence of telangiectasias is related to disease duration. Similar telangiectasias have been observed in rarer patients with other connective tissue diseases (SLE, RA, dermatomyositis and undifferentiated connective tissue diseases).  相似文献   
49.
Autogenous veins are the ideal substitute for bridging venous defects. Experimentally, fresh homografts have patency rates comparable to autografts. However, a method of preservation must be employed if homografts become practical for clinical use. In this study, homografts were frozen, irradiated, and stored for a total of 6 weeks. Following femoral venous reconstruction, patency rates between frozen, irradiated homografts and fresh autografts were compared and found to be similar over a 6 month period. Recanalization of the frozen, irradiated homografts occurred at the same rate as did that of the autografts. This study concludes that cryopreservation and irradiation are suitable methods of preservation that do not adversely affect patency. In addition irradiation will sterilize tissue and may decrease the potential of the graft to stimulate the recipient's immunologic system.  相似文献   
50.
Aerial parts of SENECIO FILAGINOIDES yielded two new furanoeremophilane type sesquiterpenoids: 6alpha-acetyloxy-10betaH-furanoeremophil-1-one, 1 and 6alpha-tiglinoyloxy-10betaH-furanoerernophil-1-one, 2. Their structures have been elucidated by spectroscopic data. From roots and aerial parts of S. PINNATUS 1alpha-hydroxy-6betaangeloyloxy-10alphaH-furanoeremophil-9-one, 3 has been isolated.  相似文献   
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