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91.
The ability of lonidamine (LND), an energolytic derivativeof indazole-carboxylic acid, to modulate the cytotoxic activityof cisplatin (CDDP) and epidoxorubicin (EPI), singly orin combination, was investigated in two human breastcancer cell lines (MCF7 and T47D). A 72-hrpost-incubation with a non-cytotoxic concentration of LND (75M) increased the activity of a 1-hr CDDPtreatment as well as that of a 1to 16-hr EPI treatment. A different pattern ofinteraction among the drugs and modulator was observedas a function of the sequence of drugtreatment. Specifically, supra-additive or additive effects of thecombination were obtained in the two cell linesaccording to the different treatment schemes. In particular,the maximum potentiation was observed in MCF7 cellssimultaneously exposed to CDDP, EPI and LND for1 hr and then post-incubated with LND for72 hr, and in T47 first exposed toEPI and LND, then to CDDP and LND,and finally post-incubated with LND. Flow cytometric analysisof MCF7 cell distribution in the different cyclephases showed that combined treatment with EPI/CDDP/LND wasable to stabilize cell cycle perturbations (mainly G2Maccumulation) induced by individual agents. The ability ofLND to potentiate CDDP and EPI cytotoxicity, andthe consideration that LND causes side effects differentfrom those caused by alkylating agents and anthracyclines,make this compound an attractive candidate for multidrugcombination therapy in breast cancer.  相似文献   
92.
Several patients with the Silver-Russell syndrome (SRS) attending our Genetics Clinic were diagnosed as having persistent metabolic acidosis. Since this abnormality has not been reported previously in the SRS, we reexamined 33 SRS patients to evaluate the frequency and type of metabolic acidosis, the clinical and laboratory findings, and the growth pattern in SRS patients with and without metabolic acidosis. Among them, 14 had a consistent decrease in HCO levels. Renal studies in acidotic patients showed urine pH of 5.8 and 24 h urine calcium of <2.4 mg/kg/24 h; serum creatinine, excretion of glucose, and aminoacids were normal, as were renal ultrasound and excretory urography findings. These data supported the diagnosis of renal tubular acidosis, probably type II; the patients were treated with oral bicarbonate and acidosis was corrected successfully. Clinical manifestations were similar in acidotic and non-acidotic patients. The nutritional indices at diagnosis and at last evaluation (at least 8 months after diagnosis) were abnormally low in all patients; however, acidotic patients, treated with bicarbonate, showed an improvement of nutritional status particularly in the weight/height index, although the difference between groups after follow-up did not reach statistical significance. We suggest that metabolic acidosis due to renal tubular acidosis, probably type II, may occur in children with the SRS and should be looked for and treated in all patients. © 1995 Wiley-Liss, Inc.  相似文献   
93.
Summary Data derived from a psychiatric case-register are presented on the attrition of the cohort of theold long-stay in-patients, and the accumulation of thenew long-stay cases in Lomest, a town in northern Italy, from 1975 to 1980. The characteristics of high user groups of out-patients attending the non-residential services are also described. The analysis seeks to provide some information on who has been left behind by the massive deinstitutionalization programme that has been carried out in Italy since 1970.  相似文献   
94.
OBJECTIVE: The present study was carried out to evaluate the safety and immunogenicity of the Haemophilus influenzae type b-CRM197 (Hib-CRM197) conjugate vaccine in relation to the change of adjuvant from aluminum hydroxide to aluminum phosphate (AlPO4). METHODS: The present study was a clinical phase II, observer-blind, randomized, multicenter, controlled study. Subjects were healthy infants aged 6-12 weeks, eligible for expanded program of immunization (EPI) routine vaccination and admitted to Hacettepe University Department of Social Pediatrics and Gülveren Health Center, Ankara. A total of 520 healthy infants were randomized in a 2:2:1 ratio to receive at either Chiron Hib/AlPO4 vaccine or VaxemHib (aluminum hydroxide adjuvant) vaccine or HibTiter (no adjuvant). Vaccines were administered simultaneously with routine diphtheria, tetanus and pertussis (DTaP) and oral polio vaccine (OPV) vaccines at 2, 4 and 6 months of age. Blood samples for anti-plain polysaccharide (PRP) antibody measurement were collected before the first vaccination and 1 month after the last vaccination. After each vaccination parents filled out a diary for 7 days. RESULTS: Out of 520 subjects enrolled, 514 received three doses and were included for safety analysis. Local and systemic reactions occurred with low and similar frequencies in all groups. Only erythema was more common in Chiron Hib/AlPO4 vaccine (19, 10, 11% in Chiron Hib/AlPO4, VaxemHib and HibTiter, respectively, P < 0.05). Nine serious adverse events were reported in seven cases of which none were related to vaccines. A total of 504 subjects were included in the immunogenicity analysis. The three vaccines were highly immunogenic and equivalent in terms of percentage of acquisition of long-term protective levels. The anti-PRP geometric mean titers were 9.9, 8.3 and 5.14 micro g/mL, respectively (P < 0.05). CONCLUSIONS: The use of aluminum compounds adjuvants in Hib-CRM197 conjugate vaccines does not impact the safety profile, while it does increase the magnitude of anti-PRP antibody titers.  相似文献   
95.
Nimesulide release from micronized and unmicronized drug particles was tested at pH 7.4 by measuring the transfer to dimyristoylphosphatidylcholine liposomes (multilamellar and unilamellar vesicles), chosen as a biomembrane model. The perturbing effect of increasing molar fractions of pure nimesulide on the thermotropic behaviour of dimyristoylphosphatidylcholine liposomes was investigated by differential scanning calorimetry. In order to study the drug dissolution process by its uptake into void liposomes, measurements were carried out on suspensions of blank liposomes added to weighed amounts of free powdered nimesulide (micronized and unmicronized). The amount of drug transferred was quantified by comparing the effect caused by the dissolved and released drug to that caused by the free drug that had been previously molecularly dissolved in the liposomes. The calorimetric results show that the dissolution rate depends on the nimesulide form (micronized or unmicronized), and that the transfer to the void liposomes is quicker when the drug is in a micronized form. The uptake was faster when unilamellar vesicles were used instead of multilamellar vesicles because of the greater lipid surface. The calorimetric technique could represent an alternative 'in vitro' method that can be applied to the study of the dissolution kinetics directly at the site of drug uptake, mimicking a biological system.  相似文献   
96.
PURPOSE: Stroma cells play a relevant role in tumor development and progression. We investigated the activity of herceptin (HER), a humanized monoclonal antibody widely used for the treatment of HER2-overexpressing epithelial cancer, toward stroma cell lines L87/4 and L88/5. EXPERIMENTAL DESIGN: We studied the antiproliferative potential of HER and role of human serum in HER activity. We also investigated the ability of HER to alter ancillary functions of L87/4 and L88/5, such as support to long-term hematopoiesis, growth factor production, breast cancer cell adhesion, and proliferation. RESULTS: Flow cytometry showed that HER2 membrane expression in L87/4 and L88/5 stroma cells was intermediate between the expression in HER2-negative/dim MCF-7 breast cancer cells and HER2-bright SK-BC3 breast cancer cells. HER2 gene amplification was not detected by fluorescence in situ hybridization in either stromal cell lines. HER significantly inhibited L87/4 and L88/5 proliferation. Mean ID(50)s were found to be 2000 and 1700 micro g/ml for L87/4 and L88/5, respectively, after 3-day exposure and 800 micro g/ml for both cell lines after 9-day exposure. The presence of 10% human serum in the culture increased HER inhibitory activity. IC(50) of stroma cells was found to be intermediate between HER2-bright breast cancer cells (SK-BC3) and HER2-negative/dim breast cancer cells (MCF-7). The drug did not significantly affect the ability of stroma cells to support long-term hematopoiesis in the cobblestone area forming cell assay. In contrast, in coculture assay, MCF7 cells demonstrated a worse adhesion and growth capability on HER-treated stroma layers when compared with untreated stroma. Moreover, HER significantly reduced vascular endothelial growth factor production by L88/5 cells. CONCLUSIONS: Our data support the novel finding that HER may have a relevant activity against stroma cells.  相似文献   
97.
98.
PURPOSE: p27(Kip1) is a member of the Cip1/Kip1 family of cyclin-dependent kinase inhibitors and is a potential tumor suppressor gene. Low levels of p27 are associated with poor prognosis in a variety of gynecological tumors, including breast, ovarian, and cervical carcinomas. The role of p27 in endometrial cancer remains controversial. EXPERIMENTAL DESIGN: In the present study, p27 protein expression was investigated by immunohistochemistry in a series of 217 endometrial adenocarcinomas and, where present, in synchronous normal endometrium, simple and complex hyperplasia (with or without atypia), and cystic atrophy. The relationship between p27 expression and clinical outcome was also evaluated. RESULTS: Immunohistochemical analysis revealed a significant loss of p27 expression from normal (33%) through hyperplastic endometrium (50%) to endometrial adenocarcinomas (71%; P 相似文献   
99.
Objective To estimate the risk of specific adverse neonatal events resulting from the combined effects of prematurity and low birthweight in very preterm infants (delivered at 24–31 weeks of gestation)
Design A cohort study of specific adverse neonatal events in preterm infants born at between 24 and 31 weeks of gestation.
Setting Pavia, Italy.
Population Two hundred and thirty singleton infants with sonographically confirmed gestational age, delivered at 24 to 31 weeks of gestation.
Methods To evaluate the impact of a lower than expected birthweight on selected neonatal events independently of gestational age, we calculated birthweight standard deviation scores (differences between actual birthweight and fitted birthweight divided by fitted standard deviation) for each week of gestation.
Results After adjustment for gestational age and other confounders, there was a significant linear trend relating a decreasing birthweight SDS to an increased likelihood of neonatal death, intraventricular haemorrhage, severe respiratory distress syndrome, and acidosis. Compared with infants with SDS 0 ( 50th centile of birthweight), infants with birthweight SDS < −1 (< 16th centile) had increased odds for neonatal death [odds ratio (OR) 3.7, 95% confidence interval (CI) 1.42–9.6], grade III-IV intraventricular haemorrhage (OR 17.5, 95% CI 4.04–75.9), and neonatal acidosis (OR 3.22, 95% CI 1.41–7.4). The significance of birthweight SDS as a predictor of neonatal outcome, however, was lower than that of gestational age.
Conclusions A lower than expected birthweight affects the likelihood of several adverse neonatal events in very preterm infants. However, a decreasing birthweight SDS affects neonatal outcome less than decreasing gestation does.  相似文献   
100.
OBJECTIVE: Retrospective study and review of the complications other than those related to the facial nerve and hearing, encountered in acoustic neuroma surgery. Also, an evaluation of hospital stay and its relation with various factors. STUDY DESIGN: Retrospective case review. SETTING: Tertiary neurotologic and skull base referral center. PATIENTS: A series of 707 patients who underwent surgical removal of acoustic neuroma from April 1987 to December 2001. INTERVENTIONS: The surgical approaches used were the enlarged translabyrinthine approach, the enlarged middle fossa approach, and the retrosigmoid approach. In a small number of cases, the operations were performed through other approaches. MAIN OUTCOME MEASURES: The duration of hospital stay and appearance of complications in the perioperative period along with their management. Results related to the facial nerve and hearing were not considered in this study. RESULTS: The most frequent complication was abdominal subcutaneous hematoma (site of fat harvest), which occurred in 23 patients (3.2%). Cerebrospinal fluid leak was present in 20 patients (2.8%), 15 of whom needed revision surgery. Other complications included VIth cranial nerve dysfunction in 12 cases (1.68%), subdural hematoma in 3 cases (0.4%), cerebellopontine angle hematoma in 4 cases (0.6%), cerebellar edema in 2 cases (0.28%), brainstem hematoma in 1 case (0.14%), transitory aphasia in 1 case (0.14%), and lower cranial nerve dysfunction in 1 case (0.14%). Mortality occurred in only one case (0.14%). Medical complications seldom occurred. The postoperative hospital stay ranged from 2 to 36 days, with an average of 6.4 days. The overall hospital stay diminished over time from 10.2 days in 1987 to 1990, to 4.9 days in 2001. There was a significant relation between hospital stay and tumor size, approach used, and presence/absence of complications. CONCLUSIONS: Perioperative complications in acoustic neuroma surgery do exist, but this study demonstrated how low the incidence is. The authors believe that the low percentage of complications is mainly attributable to the majority of operations being carried out in specialized clinics, where they are considered routine operations. They believe that following individualized approaches, depending on tumor size and on the preoperative function of the cranial nerves, is the proper way to reach a significant reduction in complications while maintaining a high percentage of total tumor removal. The results of this study, considered as a basis of comparison with other studies, will certainly be useful in preoperative patient counseling.  相似文献   
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