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91.
Interleukin-6 (IL-6) plays a pathogenetic role in B-cell malignancies and is a growth factor for multiple myeloma (MM) cells. Elevated serum IL-6 levels and a higher proliferative activity of bone marrow plasma cells are poor prognostic factors in MM patients. In addition to clinical trials with anti-IL-6 monoclonal antibodies, an alternative therapeutic approach based on the use of IL-6 receptor (R) super-antagonists (Sants) has been proposed. Sants are variants of the native cytokine characterized by a wild type affinity for the ligand-specific receptor chain IL-6R alpha and by a reduced ability to bind and/or dimerize the signaling chain gp-130. We report the in vitro effects of four different Sants on cell kinetic modulation and induction of apoptosis of primary cells from MM patients. Ten MM samples were cultured in the presence of four different Sants and heterogeneous effects in terms of reduction of proliferation and induction of apoptosis could be observed. A decrease of the S phase cells (> or = 25%) coupled with the induction of apoptosis was obtained in 4/10 samples: three of these samples had a diploid DNA stem line and an inferior initial percentage of S phase cells. Serum IL-6 concentrations did not correlate with the anti-proliferative activities of the Sants. Cell growth inhibition was observed especially in samples with soluble IL-6R serum concentrations > 200 ng/ml. We conclude that Sants can exert antiproliferative effects on selected MM samples. Such effects may depend on the availability of large amounts of soluble IL-6R. Further studies should aim at defining the conditions necessary for optimal antiproliferative activity.  相似文献   
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BACKGROUND: Motion sickness is considered an important risk factor for postoperative nausea and vomiting in children. The aim of this study was to verify the impact of motion sickness on the incidence of vomiting after routine surgery in children, and to compare the incidence of vomiting, after combined regional/general anaesthesia, using either halothane or sevoflurane. METHODS: We prospectively studied 420 children (369 males and 51 females) who received general anaesthesia and inguinal field block for common paediatric surgery. The children were randomly allocated into one of two groups (halothane or sevoflurane). In the 200 children in the first group (H), general anaesthesia was induced and maintained with halothane, whereas in the 220 children in the second group (S), anaesthesia was induced and maintained with sevoflurane. RESULTS: There were 79 children with a prior history of motion sickness (MS+) and 341 without such a history (MS-). In the MS+ population, the incidence of vomiting was similar in both H and S groups, being around 33%. However, repeated episodes of vomiting in MS+ children were more frequent when halothane was used. In the MS- group, the incidence of vomiting was significantly greater in the H group (19%) than in the S group (8%). CONCLUSIONS: In the postoperative period, we found that MS+ children vomit more than MS- children, regardless of the inhalation anaesthetic used. However, MS- children displayed a higher incidence of vomiting when halothane was used rather than sevoflurane.  相似文献   
93.
PURPOSE: To define the cyclophosphamide (CTX) maximal tolerated dose when combined with fixed doses of gemcitabine, fluorouracil (5-FU) and folinic acid (leucovorin, LFA) in metastatic breast cancer patients pretreated with anthracyclines and taxanes. METHODS: Metastatic breast cancer patients aged < or = 75 years, with ECOG performance status 0-2, were eligible, provided that they had received previous anthracycline- and taxane-based chemotherapy for the advanced disease. Chemotherapy consisted of gemcitabine 1,000 mg/m(2), 5-FU 425 mg/m(2), LFA 100 mg/m(2) and escalating doses of CTX, starting from 500 mg/m(2), on days 1 and 8 every 3 weeks. The dose escalation was stopped if dose-limiting toxicity (DLT) occurred in > 33% of patients of a given cohort. After the definition of DLT, a further escalation with the addition of granulocyte colony-stimulating factor (G-CSF; on days 3-5 and 10-12) was planned. RESULTS: Since March 1999, 69 patients have entered this trial through seven different cohorts. The dose escalation was stopped at the CTX dose of 600 mg/m(2) since 3/6 patients showed DLT. A further dose escalation was attempted in the presence of G-CSF support. A CTX dose of 800 mg/m(2) proved to be safe and was chosen for the phase II. A total of 33 patients were treated at this dose level. The treatment was fairly well tolerated, grade 3-4 neutropenia and thrombocytopenia occurring in 38 and 16% of patients, respectively. No cases of sepsis or bleeding were registered. Four patients required a packed red blood cell transfusion. Severe nonhematologic toxicity was also uncommon, occurring in 10 patients. Three complete and 24 partial responses were recorded for an overall response rate of 38% (95% CI = 26-50). Two complete and 12 partial responses were recorded in the 33 patients treated in the phase II for an overall response rate (ORR) of 42% (95% CI = 25-61). CONCLUSIONS: The gemcitabine-CTX-5-FU/LFA combination is a well-tolerated treatment for poor-prognosis breast cancer patients with previous exposure to anthracyclines and taxanes. With the addition of G-CSF, a cumulative CTX dose of 1,600 mg/m(2) can be safely delivered every 3 weeks. The evidence of an ORR approaching 40% is very promising and justifies further evaluations in this subset of patients.  相似文献   
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95.

Background  

The aim of the study was to investigate whether p503S, p504S and p510S gene expression in peripheral-blood be useful as a diagnostic or prognostic marker of prostatic cancer.  相似文献   
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98.
The prevalence of obesity has reached epidemic dimension in industrialized countries and it is known that obesity is associated with increased risk of cardiovascular morbidity and mortality. Commonly, obesity is defined by the Body Mass Index (BMI). However, BMI fails to consider body fat distribution. The relationship between the risk of metabolic-cardiovascular diseases and body fat distribution indices such as the waist-to-hip ratio (WHR) and the waist circumference, rather than measures of the degree of body fatness as expressed by BMI, has long been recognized. Recently, clinical and epidemiological research has found waist circumference to be the best anthropometric indicator of both total body fat and intra-abdominal fat mass. Android or visceral obesity is associated with metabolic syndrome and increased cardiovascular morbidity and mortality through a variety of molecular mechanisms possibly linking the metabolic syndrome to hemostatic and vascular abnormalities. Obesity guidelines suggest the need for weight reduction using behavioural change to reduce caloric intake and increasing physical activity. A realistic goal for weight reduction is to reduce body weight by 5% to 10% over a period of 6 to 12 months. Combined intervention of a low calories diet, increased physical activity, and behaviour therapy provides better outcomes for long-term weight reduction and weight maintenance than programs that use only one or two of these modalities. The drugs used to promote weight loss have been anorexic drugs or appetite suppressants. All classes of anorexic drugs affect neurotransmitters in the brain. The new agent sibutramine has norepinephrine and serotonin effects. Another new agent, orlistat, has a different mechanism of action, the reduction of fat absorption. Weight loss drugs approved by the FDA for long-term use may be useful as an adjunct to diet, physical activity and behaviour therapy for patients with a BMI of > or =30 with no concomitant obesity-related risk factors or diseases, and for patients with a BMI of > or =27 with concomitant obesity-related risk factors or diseases.  相似文献   
99.
The effect of PD-168077 (N-methyl-4-(2-cyanophenyl)piperazynil-3-methylbenzamide maleate), a selective D4 dopamine receptor agonist, injected into the paraventricular nucleus of the hypothalamus on penile erection was studied in male rats. PD-168077 (1-200 ng) induced penile erection in a dose-dependent manner. The minimal effective dose was 50 ng, while the maximal response was found with 200 ng of the compound, which increased penile erection episodes from 0.3+/-0.03 to 1.7+/-0.21. The proerectile effect of PD-168077 was reduced almost completely by L-745,870 (3-(4-[chlorophenyl]piperazin-1-yl)-methyl-1H-pyrrolo[2,3-B]pyridine trihydrochloride), a selective D4 dopamine receptor antagonist, (1 microg) given into the paraventricular nucleus before the D4 dopamine agonist, and by other nonselective dopamine receptor antagonists, such as haloperidol (1 microg) and clozapine (1 microg), which block all dopamine receptor subtypes. The pro-erectile effect of PD-168077 was also reduced by the NO synthase inhibitor NG-nitro-L-arginine methylester (25 microg), but not by the oxytocin receptor antagonist d(CH2)5Tyr(Me)2-Orn8-vasotocin (1 microg), when given into the paraventricular nucleus. In spite of its inability to prevent the pro-erectile effect of PD-168077 when given in the paraventricular nucleus, d(CH2)5Tyr(Me)2-Orn8-vasotocin (1 microg) reduced almost completely PD-168077-induced penile erection when given into the lateral ventricles. The present results show that D4 dopamine receptors present in the paraventricular nucleus may influence penile erection by modulating the activity of paraventricular oxytocinergic neurons mediating erectile function.  相似文献   
100.
This study was designed to test whether chronic treatment with the metabotropic glutamate receptor 5 (mGlu5R) antagonist MPEP showed antiparkinsonian effects in rats unilaterally lesioned with 6-hydroxydopamine (6-OHDA) (a "classic" model of Parkinson's disease, PD), and to evaluate whether chronic MPEP influenced the functional properties and/or the expression of striatal mGlu5Rs. Wistar rats were lesioned with 6-OHDA and then treated with MPEP (3 mg/kg/day, i.p.) or its vehicle over 2 weeks. Chronic MPEP did not induce measurable antiparkinsonian effects, since no differences were found between MPEP- and vehicle-treated animals in the pattern of L-DOPA-induced contralateral rotations. In corticostriatal slices taken from animals chronically treated with MPEP, the functional effects of the mGlu5R agonist CHPG were significantly reduced in the lesioned vs. the intact side, while no changes were found in slices taken from vehicle-treated rats. The binding of [3H]MPEP to striatal membranes showed that neither the maximal number of binding sites (Bmax) nor the dissociation constant (Kd) were changed by the lesion and/or by chronic MPEP. While chronic MPEP did not potentiate L-DOPA-induced turning in a classical model of PD, its ability to reduce mGlu5R-associated signal could help to explain the neuroprotective/antiparkinsonian effects observed in other models of PD.  相似文献   
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