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91.
To evaluate the clinical value of the concurrent use of methotrexate administered immediately before paclitaxel, we investigated the efficacy and toxicity of this two-drug combination administered as palliative second line therapy in patients with advanced urothelial cancer. The design of the schedule and sequence used was based on our previous preclinical data from a comparative study on sequential combinations of paclitaxel and methotrexate in a human bladder cancer cell line. As a confirmation study, we further extended our analysis of in vitro synergism. Twenty patients with advanced transitional cell carcinoma of the urinary tract previously treated with platinum-based therapy, with adequate renal function and a performance status > or = 60 were considered eligible. They received therapy with methotrexate 30 mg/m2 administered as an intravenous bolus, followed immediately by paclitaxel 175 mg/m2 given as a 3-hr infusion, both on day 1 every 21 days. Therapy was given on a compassionate-use basis until either disease progression was documented or the patient became intolerant to therapy. In vitro data were further analyzed using the median-effect principle and the combination index method. Twenty patients with metastatic (16 patients) or locally advanced disease (four patients) received a median of three cycles of therapy. Of the 19 patients assessable for response, there were six partial responses and seven disease stabilizations with no complete responses. Median duration of response was 3 months (range, 2-7) and median survival was 5 months. Three patients developed grade 3-4 neutropenia, one patient had grade 3 anemia, four patients had grade 2-3 sensory neuropathy, and three patients had myalgias. Eighteen patients developed alopecia. Gastrointestinal toxicity was mild. One patient died after the first cycle due to pulmonary thrombo-embolism and could not be evaluated for response. The synergistic in vitro effect of the concurrent combination was confirmed in analyses performed under mutually exclusive and mutually nonexclusive criteria. In conclusion, the combination of methotrexate and paclitaxel at this dose and sequence is feasible and active as a palliative therapy in patients with advanced urothelial cancer previously treated with platinum-based therapies. This schedule merits further investigation in a phase-II trial.  相似文献   
92.
We report a case of bronchobiliary fistula between a liver hydatid cyst and the middle lobe of the right lung. It is also reviewed the etiology, pathogenesis, clinical features, diagnosis and treatment of bronchobiliary fistulas.  相似文献   
93.
The effects of nitric oxide synthase (NOS) inhibitors, N(omega)-nitro-L-arginine and 7-nitroindazole, and the NOS substrate L-arginine on kainic acid (KA)-induced microglial reactivity and stress response were studied in the hippocampus 7 and 1 days after KA, respectively. Density of peripheral-type benzodiazepine receptors was measured as an index of microglial reactivity. Histological damage in hippocampus was evaluated at 7 days by neuronal counting. KA increased the maximal number of binding sites (B(max)) versus controls. Administration of either 7-nitroindazole (25 mg/kg) or N(omega)-nitro-L-arginine (20 and 50 mg/kg) 24 hr before KA, further increased B(max). This later effect was abolished by L-arginine (1 g/kg), which given 24 hr before KA decreased B(max) to control values. Also, KA-induced HSP72 stress response was attenuated by pre-treatment with L-arginine. Histological evaluation showed reduced cell numbers in the pyramidal cell layer of the hippocampus in groups receiving KA, either alone or in combination with 7-nitroindazole. Administration of L-arginine before KA attenuated neuronal loss in CA3 but not CA1. A clear protective effect was observed, however, in CA1 and CA3, in rats receiving both L-arginine plus 7-nitroindazole before KA. The results show that the combination of a NO substrate with a NOS inhibitor reduces the neurotoxic effects of KA in the rat hippocampus. This study suggests that extremely fine regulation of NO levels in the different neural cell types can modulate excitotoxicity.  相似文献   
94.
Genetic immunization with a single injection of dendritic cells (DCs) expressing a model melanoma antigen generates antigen-specific, MHC-restricted, protective immune responses. After initiating the immune response, additional vaccinations may increase the protection or conversely downregulate the immune response. Groups of mice were vaccinated several times with DCs transduced with the MART-1 gene, and the anti-tumor protection was compared with that of mice receiving a single vaccination. C3H mice had poorer protection from a syngeneic MART-1-expressing tumor challenge with multiple vaccinations. This was accompanied by lower levels of splenic CTL effectors and a shift from a type 1 to a type 2 cytokine profile. On the contrary, multiple vaccinations in C57BL/6 mice generated greater in vivo antitumor protection with no decrease in splenic CTLs and no cytokine shift. Antiadenoviral humoral or cellular immune responses did not seem to contribute to these effects. When studies were performed in Fas receptor-negative C3H.(lpr) mice, the adverse effect of multiple vaccinations disappeared, and there was no cytokine shift pattern. In conclusion, C3H mice but not C57BL/6 mice receiving multiple vaccinations with DCs expressing the MART-1 tumor antigen show decreased protection associated with deviation from a type 1 to a type 2 cytokine response attributable to a Fas-receptor mediated clearance of antigen-specific IFN-gamma-producing cells.  相似文献   
95.
Objective: Studies focusing on telomere attrition in newborns and what factors could be involved in this issue are sparse; most reports have been in adult populations. Thereby, the aim of this study was to present an overview of what is currently known about the relationship between environmental exposure of the fetus during pregnancy and telomere length outcomes in early life.

Methods: The MEDLINE (via PubMed) and Bireme databases were searched for studies published until 1 June 2016. Studies that reported telomere length measurement from birth to age 1 year were included.

Results: Fifteen articles were selected that evaluated possible relationships between maternal smoking, hyperglycemia, hypertension, sleep apnea, psychological stress, folate concentration in early pregnancy, and radiation, in addition to small-for-gestational-age status and preterm birth. We found that sleep apnea, psychological stress, and folate concentration in early pregnancy were associated with telomere shortening in the newborn. No association was found with radiation, small-for-gestational-age status, or preterm birth. Results for maternal smoking, hyperglycemia, and hypertension were conflicting, and further studies should be considered.

Conclusion: The actual clinical implications of these findings have yet to be investigated.  相似文献   

96.
The institution and development of unit dose drug distribution and clinical pharmacy in a general hospital (Granollers, Spain) is described. The new role of pharmacists in clinical areas is discussed.  相似文献   
97.
Morales C  Ribas M  Aiza G  Peinado MA 《Oncogene》2005,24(45):6842-6847
Alternative genetic pathways characterized by specific genetic profiles and exhibiting distinctive biological and clinical features have been proposed in colorectal carcinogenesis. Methotrexate (MTX) is a potent inhibitor of the dihydrofolate reductase (DHFR) enzyme, which is essential for DNA synthesis and cell growth. We have evaluated the association between different genetic features and the capacity to develop MTX resistance in colon cancer cell lines representative of alternative genetic pathways. Three aneuploid cell lines (HT-29, SW480, and SK-CO-1) showed pre-existing amplifications, but only one (HT-29) developed MTX resistance, showing amplification of the DHFR gene at 5q12-14 (>20-fold amplification and presence of extrachromosomal double minutes). Failure to develop resistance was attributed to the absence of two complete chromosomes 5 in SW480 and SK-CO-1 cells. Four near-diploid cell lines (LoVo, HCT116, DLD-1 and KM12C) and two aneuploid KM12C-derived metastases (KM12SM and KM12L4A) developed MTX resistance but none exhibited DHFR amplification. All resistant cells without DHFR gene amplification showed microsatellite instability. We conclude that chemoresistance capacity and the mechanism of chemoresistance are related with the genetic pathway and the karyotypic features of colon cancer cells.  相似文献   
98.
We investigated the intestinal transport of D-glucose (D-Glc) and 3 essential amino acids in a model of intestinal inflammation, and the effects of dietary supplementation with animal plasma proteins on this function. Wistar Lewis rats were fed a diet containing an isonitrogenous amount of milk protein (control group) or a diet supplemented with either spray-dried animal plasma (SDAP) or immunoglobulin concentrate (IC) from porcine plasma, from d 21 of life (weaning) until d 35. On d 30 and 33, rats were challenged intraperitoneally with Staphylococcus aureus enterotoxin B (SEB; groups SEB, SEB-SDAP, and SEB-IC) and on d 35, brush border membrane vesicles (BBMVs) were prepared and used for transport and binding studies. Administration of SEB reduced D-Glc transport across sodium glucose transporter 1 [SGLT1; 20% reduction in maximal transport rate (Vmax); P < 0.05], without affecting the Michaelis constant (Km). The results from specific phlorizin binding, Western blot, and immunohistochemistry supported the view that the effects of SEB are due to reduced expression of D-Glc transporters in the apical membrane. SEB increased the passive diffusion constant (Kd) for D-Glc 3-fold (P < 0.05). SEB did not affect mediated or passive amino acid fluxes of L-leucine, L-methionine, or L-lysine. Dietary SDAP increased the D-Glc Vmax in the SEB group without affecting the passive component. Changes in d-Glc Vmax due to SEB and to the dietary treatments were correlated with changes in the number of SGLT1 transporters present in the BBMVs (r = 0.9468; P < 0.05). Dietary IC had no observed effect. We estimate that, in rats challenged with SEB, SDAP supplementation can increase glucose absorption by 8-9% during the interdigestive periods.  相似文献   
99.
trans-Resveratrol was reported to have health benefits including anticarcinogenic effects and protection against cardiovascular disease. One of the mechanisms by which it exerts its action is through modulating the estrogen response systems. Because estrogen is involved in male reproductive biology, we investigated the effect of trans-resveratrol on testis and spermatogenesis. Adult male rats were divided into 2 groups. The treated group was administered by gavage 20 mg/(kg . d) of trans-resveratrol suspended in 10 g/L of carboxymethylcellulose for 90 d, whereas the control group received only carboxymethylcellulose during the same period. The relative weight of testes did not differ between the groups. However, the diameter of the seminiferous tubules was significantly reduced from 437.5 +/- 0.1 mum in the controls to 310.9 +/- 0.1 mum in the resveratrol-treated rats. This decrease was accompanied by a significant increase in tubular density, from 3.20 +/- 0.18 in controls to 6.58 +/- 0.18 tubules/mm(2) in the treated group. Moreover, sperm counts were significantly greater in the resveratrol-treated rats (24.8 +/- 3.30 x 10(7)) than in the control group (14.1 +/- 0.80 x 10(7)), but sperm quality did not differ. Serum concentrations of gonadotrophins and testosterone were significantly higher in the resveratrol-treated group. We identified a novel activity of trans-resveratrol. The daily oral administration of this phytochemical to adult male rats enhanced sperm production by stimulating the hypothalamic-pituitary-gonadal axis, without inducing adverse effects.  相似文献   
100.
BACKGROUND: The likely increased incidence of hepatocarcinoma (HCC) in HIV-1 infected patients has not yet been demonstrated. METHODS: We studied all cases of HCC occurring in HIV-1 infected patients in our hospital during the past 15 years. Incidence and survival time were compared with those of the general population in the same area and the same time of the study. RESULTS: We found 6 cases of HCC in a cohort of 2383 HIV-1 infected patients between 1986 and 2001. This is a higher than expected incidence rate of HCC compared with the general population, with a standardized incidence ratio of 13.95. Chronic hepatitis virus infection and alcohol abuse were present in four and two cases, respectively. In one patient, no liver disease was known before the HCC and the surrounding liver was normal in the necropsy study. CONCLUSION: The improved survival of patients on highly active antiretroviral treatment (HAART) and the increasing incidence of end-stage liver disease in these patients caused by chronic hepatitis virus infection and alcohol abuse may be responsible for an increase in the incidence of HCC in HIV-1 infected patients.  相似文献   
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