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41.
L Rocchi I Feola M Calvani S D'Iddio C Alfarone M Frascarelli 《Drugs under experimental and clinical research》1986,12(8):707-711
The effects of chronic administration of L-carnitine were evaluated by EMG analysis in 20 uraemic patients undergoing periodical haemodialysis (mean duration of dialysis 34.7 months). No important changes in motor conduction velocity or distal latency of the external popliteal nerve were found after the treatment, while a reduction in the number of polyphasic muscle action potentials was observed. After carnitine administration, an increase of total EMG power was noted and the spectral array showed a progressive shift towards lower frequencies in 8 patients who had shown higher values. These results suggest that carnitine has a prevalent "myotrophic" effect. 相似文献
42.
Neurohumoral control of gallbladder motility in healthy subjects and diabetic patients with or without autonomic neuropathy 总被引:4,自引:0,他引:4
Stefano Fiorucci MD Rachele Bosso MD Luciano Scionti MD Silvana Disanto MD Bruno Annibale MD Gianfranco Delle Fave Antonio Morelli MD 《Digestive diseases and sciences》1990,35(9):1089-1097
Patients affected by diabetes mellitus are reported to have an increased incidence of gallbladder abnormalities. The pathophysiologic mechanisms for this phenomenon are unclear. In the present study ultrasonography was used to determine gallbladder emptying in response to a meal or separate cephalic or hormonal stimulation in 21 diabetic patients and 10 healthy subjects. Gallbladder emptying and refilling after a meal were similar in diabetic patients and healthy subjects. When diabetics were divided according to the presence or absence of cardiac autonomic neuropathy (AN), a significant reduction of gallbladder emptying in response to cephalic stimulation was found in diabetics with AN (P<0.01 in comparison with diabetics without AN or healthy subjects). A dose-response curve of gallbladder emptying in response cerulein, a cholecystokinin analog, at concentrations of 0.25, 1, and 4 g/kg/min was evaluated. No differences of gallbladder emptying were found in the three groups of subjects, indicating that gallbladder sensitivity to hormonal stimulation is not changed in diabetic patients with or without AN. Diabetic patients with AN have a significant reduction of gastric acid output and pancreatic polypeptide (PP) secretion in response to cephalic stimulation (P<0.05 in comparison with diabetic patients without AN or healthy subjects). Cerulein-induced PP secretion was similar in all three groups of subjects (P>0.05). This study indicates that in diabetic patients with AN, gallbladder emptying as well as gastric acid and PP secretions induced by neural stimulation are markedly reduced in comparison to diabetics without AN. 相似文献
43.
Two idiopathic thrombi loosely attached to the left ventricular wall were detected by dynamic three-dimensional echocardiography. Because the thrombi were shown to be lobulated and extremly mobile, urgent surgical treatment was mandatory. Three-dimensional image reconstruction enhanced appreciation of left ventricular thrombi by enabling accurate imaging of the spatial relationship between the thrombus, the myocardial wall, and the valvular apparatus, so that the most advantageous surgical access could be chosen. 相似文献
44.
The changes in hemorrhagic activity, proteolytic activity on gelatin and the lethal potency of four Bothrops venoms treated at different pH values or with EDTA were studied. Venoms from B. alternatus, B. jararaca, B. moojeni and B. neuwiedii of Argentina were preincubated at pH 5.8, 5.1 or 3.8 or with EDTA and the hemorrhagic activity expressed as size of the hemorrhagic lesion or as the amount of hemoglobin extracted, the proteolytic activity on gelatin and the lethal potency were determined. Although the MHDs recorded in rats were 19–56 fold higher than those recorded in mice, the A550 extracted per gram of hemorrhagic haloes was very similar in rats or mice independent of the venom dose. Inhibition of proteolytic activity after preincubation at pH 5.1 or 3.8, agrees with the decreased amount of hemoglobin extracted from the hemorrhagic haloes, and with the increase in mean survival time after the i.p. injection to mice. Preincubation with EDTA resulted in 80% inhibition of hemorrhagic activity of B. jararaca venom and complete inhibition with the other Bothrops venoms tested. Measurement of the amount of hemoglobin extracted gives significant information in comparative studies, not available by measurement of the size of hemorrhagic haloes. 相似文献
45.
Grazia Arpino Stephanie J Green D Craig Allred Dannika Lew Silvana Martino C Kent Osborne Richard M Elledge 《Clinical cancer research》2004,10(17):5670-5676
PURPOSE: Preclinical data indicate that expression of the ErbB family of receptors, such as HER-2 and HER-1 (EGFR) may be involved in endocrine resistance. Evidence of resistance from clinical studies has been inconsistent. The present study examined whether HER-2 gene amplification or HER-1 expression predicted response to tamoxifen. PATIENTS AND METHODS: Three hundred and forty nine patients had estrogen receptor (ER)-positive breast cancer and received daily tamoxifen as initial therapy for advanced disease. HER-2 gene amplification, detected by fluorescence in situ hybridization, and HER-1 expression, evaluated by immunohistochemistry, was determined on 136 and 204 patients, respectively. RESULTS: HER-2 amplification was correlated with lower ER (P = 0.02), HER-1 positivity (P = 0.004), and HER-2 protein overexpression (P < 0.00001). The response rate was 56% for HER-2 non-amplified versus 47% for HER-2 amplified tumors (P = 0.38), and 58% for HER-1-negative versus 36% for HER-1-positive (P = 0.05). Time to treatment failure (TTF) was 7 months for non-amplified HER-2 tumors and 5 months (P = 0.007) for amplified HER-2 tumors, and there was a trend toward a better overall survival (OS) in patients with non-amplified HER-2 tumors (median 31 versus 25 months, respectively, P = 0.07). For positive versus negative HER-1 tumors, TTF was 4 versus 8 months (P = 0.08) and median survival was 24 versus 31 months (P = 0.41). Combining HER-1 expression and HER-2 gene status, patients with both negative HER-1 expression and non-amplified HER-2 had longer TTF (P = 0.001) and OS (P = 0.03) than if either were positive. In multivariate analysis, HER-2 was not an independent factor for TTF and OS, although HER-1 was significant for TTF only (P = 0.001). CONCLUSION: Patients with HER-2 amplification and HER-1 expression had lower ER levels and were modestly less responsive to tamoxifen, suggesting that molecular events in addition to those involving the ErbB receptors are important in determining the endocrine-resistant phenotype. 相似文献
46.
p15INK4b, p14ARF, and p16INK4a inactivation in sporadic and neurofibromatosis type 1-related malignant peripheral nerve sheath tumors. 总被引:1,自引:0,他引:1
Federica Perrone Silvia Tabano Federica Colombo Gianpaolo Dagrada Sarah Birindelli Alessandro Gronchi Maurizio Colecchia Marco A Pierotti Silvana Pilotti 《Clinical cancer research》2003,9(11):4132-4138
PURPOSE: Malignant peripheral nerve sheath tumor (MPNST) can arise sporadically or in association with neurofibromatosis type 1. Deletions at the 9p21 locus have been reported in these tumors. To additionally characterize the status of this chromosomal region, in this study we performed a comprehensive, mostly PCR-based molecular analysis of the three tumor suppressor genes p15(INK4b), p14(ARF) and p16(INK4a) located at the 9p21 locus in 26 cryopreserved MPNSTs. EXPERIMENTAL DESIGN: Fourteen neurofibromatosis type 1-related and 12 sporadic cases were investigated for homozygous deletion coupled with fluorescent in situ hybridization, promoter methylation, and mutational analysis, as well as m-RNA expression. RESULTS: The results showed that an inactivation of one or more genes occurred in 77% of MPNSTs and was mainly achieved through homozygous deletion (46%), which, in turn, encompassed all of the three tandemly linked genes in 83% of the deleted cases. Promoter methylation was at a less extent involved in gene silencing (18%), and no mutations were found. Loss of function at DNA level strongly correlated with loss of mRNA expression accounting for 80% of the cases. Because of the close relationship between p14(ARF) and TP53 and between p15(INK4b)/p16(INK4a) and Rb, these results support a model of a coinactivation of TP53 and Rb pathways in 75% of MPNSTs, with functional consequences on cell growth control and apoptosis. CONCLUSIONS: The inactivation of the 9p21 locus is a frequent and peculiar hallmark of MPNST genetic profile leading also to an impaired apoptosis that could be taken into account in treatment planning of these tumors. 相似文献
47.
Silvana Chiara Maria Teresa Nobile Maura Vincenti Rita Lionetto Alberto Gozza Maria Cristina Barzacchi Ornella Sanguineti Lazzaro Repetto Riccardo Rosso 《Cancer chemotherapy and pharmacology》1998,42(4):336-340
To evaluate toxicity and efficacy of chemotherapy in elderly patients (≥65 years of age) with advanced colorectal cancer,
data from two consecutive trials conducted between 1984 and 1995 at the National Institute for Cancer Research were analysed
comparing the results of treatment in those 65 years of age or older and in those younger than 65 years. Of 215 patients recruited,
82 elderly patients (median age 70 years, median performance status 1) received one of the following regimens based on 5-fluorouracil
(5-FU): (1) weekly 5-FU 600 mg/m2 i.v. bolus (30 patients); (2) weekly 5-FU 600 mg/m2 bolus plus leucovorin (LV) 500 mg/m2 2-h i.v. infusion (28 patients); (3) Weekly 5-FU 2600 mg/m2 24-h continuous i.v. infusion plus LV 100 mg 4-h i.v. infusion and 50 mg orally every 4 h for five doses (24 patients). Overall,
1071 chemotherapy cycles were administered with a median number of 12 courses per patient. The main side effects were diarrhoea,
observed in 38% of patients, stomatitis in 24% of patients and hand-foot syndrome in 13% of patients, and haematological toxicity
affected only 15% of patients. No patient suffered grade IV toxicity. In three patients chemotherapy was discontinued because
of toxicity (two patients suffered grade III diarrhoea, one patient grade III hand-foot syndrome). No significant difference
in toxicity was evident between patients older than or younger than 65 years. Analysis of median dose intensity demonstrated
no difference between the two groups. Overall objective response was observed in 18% (95% confidence limits 11–29) of elderly
patients (15/82) in comparison with 23% (95% CL 17–32) of patients <65 years of age (31/133 pts). In conclusion, chemotherapy
in elderly patients with advanced colorectal cancer is a safe and effective treatment with acceptable toxicity and comparable
objective response rates.
Received: 6 January 1998 / Accepted: 27 February 1998 相似文献
48.
Fabio Scopesi Silvana Canini Cesare Arioni Massimo Mazzella Diego Gazzolo Pasquale B Lantieri Wanda Bonacci Giovanni Serra 《The journal of maternal-fetal & neonatal medicine》2006,19(6):343-346
BACKGROUND: Recently we demonstrated an increased 2,3-diphosphoglycerate (2,3-DPG) erythrocyte concentration in rat pups subjected to nucleotide-enriched artificial feeding. DESIGN: The present study was carried out to test the hypothesis that a possible increase in 2,3-DPG concentration can also be obtained in human neonates who are fed nucleotide-enriched formula. Preterm neonates born or referred to the neonatal intensive care unit of the G. Gaslini Hospital, Genoa University, with a gestational age >30 weeks and <37 weeks were enrolled in our randomized trial. Recruitment took place within 48-72 hours from birth. Only newborns of mothers deciding not to breast-feed were eligible to be randomized for the supplemented group (FN) or non-supplemented group (RF). Breast-fed newborns were considered the control group (C). The study window (for supplementation and blood samples) was restricted to the first two weeks following birth (from the 2nd (t1) to the 16th (t2) day of life). At the end of our study, only 21 neonates were eligible for statistical analysis. RESULTS: The stimulating action of dietary nucleotides on 2,3-DPG concentration failed to be demonstrated; increases in 2,3-DPG concentration that were observed in newborns fed with nucleotide supplemented formula (FN) were comparable to those observed in newborns fed with regular formula (RF) and breast-fed newborns. CONCLUSIONS: The EC recommendation for the amount of nucleotides allowed in formula milk does not seem to be high enough to have positive effects on 2,3-DPG synthesis. Whether this possible 'pharmacological' effect can be achieved by a higher intake of ingested nucleotides and/or a change in the proportions of single nucleotides contained in milk formulas remain interesting end points to be elucidated. 相似文献
49.
Oleoylethanolamide inhibits food intake in free-feeding rats after oral administration. 总被引:3,自引:0,他引:3
Fariba Oveisi Silvana Gaetani Kevin Tai-Pang Eng Daniele Piomelli 《Pharmacological research》2004,49(5):461-466
Oleoylethanolamide (OEA) is an endogenous lipid that contributes in important ways to the peripheral regulation of food intake. When administered intraperitoneally, OEA is a potent satiety-inducing anorexiant in rats and mice [Nature 414 (2001) 209; Neuropsycopharmacology 28 (2003) 1311; Nature 425 (2003) 90]. In the present study, we show that oral administration of OEA in pH-sensitive enteric-coated capsules produces a profound and long-lasting inhibition of food intake in free-feeding rats. This effect is accompanied by a marked elevation in OEA levels in the small intestine, but not in brain or muscle. 相似文献
50.
Veridiana M Rodrigues Silvana Marcussi Rafael S Cambraia Ana L de Araújo Natael R Malta-Neto Amélia Hamaguchi Eloísa A V Ferro Maria I Homsi-Brandeburgo José R Giglio Andreimar M Soares 《Toxicon》2004,44(3):305-314
Two basic myotoxic PLA(2)s, namely BnpTX-I and II, were isolated from Bothrops neuwiedi pauloensis snake venom through three chromatographic steps: ion-exchange chromatography on CM-Sepharose, gel filtration on Sephadex G-50 and reverse phase HPLC on a C18 column. Both PLA(2)s showed a M(r) around 14,000 for the monomer and 28,000 for the dimer (as estimated by SDS-PAGE), pI approximately 7.8 and approximately 121 amino acid residues cross-linked by seven disulfide bonds. The N-terminal sequences revealed significant homology with Asp49 basic myotoxic PLA(2)s from other snake venoms. The catalytic and anticoagulant activities of BnpTX-I were higher than those of BnpTX-II. Both were able to induce cytotoxicity in vitro, as well as, myotoxicity, edema and lethality in mice. BnpTX-I also induced neurotoxic effect on mouse neuromuscular preparations and bactericidal activity on Eschericia coli and Staphylococcus aureus. After chemical modification of BnpTX-I with BPB or incubation with EDTA or Mn(2+) ions, the catalytic activity was completely abolished, while the toxic and pharmacological activities were partially reduced. Interaction with heparin inhibited the cytotoxic and bactericidal effects. Anti-BthTX-I, anti-BthTX-II and anti-115-129-C terminal antibodies strongly recognize both BnpTX-I and II. It is shown that the neurotoxic effect induced by B. neuwiedi pauloensis venom is due to the presence of myotoxic PLA(2)s. The data also corroborate the hypothesis of a partial dissociation between toxic and enzymatic domains. In addition, BnpTX-I displays a heparin binding C-terminal region, which is probably responsible for the cytotoxic and bactericidal effects. 相似文献