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21.
Neutralizing activity against dengue virus types 1--4 was observed in milk samples from 5 non-immune and 29 dengue immune women. Anti-dengue activity in milk and colostrum was found only in the lipid component. The inhibitory activity is directed against the virus and not cell surfaces. When immunoglobulin types IgM,IgA, IgG were isolated from colostrum from dengue immune women, no antibody activity was found. Anti-dengue activity in human milk did not decrease over a period of ten months after delivery. 相似文献
22.
Reduction of cell proliferative activities of gastric stump adenomatous hyperplasias after bile reflux diversion in rats 总被引:4,自引:1,他引:3
Imai Toshio; Kobayasi Shoiti; Rodrigues Maria Aparecida Marchesan; Camargo Joao Lauro Viana de; Ogawa Kumiko; Iwata Hitoshi; Tatematsu Masae 《Carcinogenesis》1993,14(9):1765-1769
Previously we reported the majority of lesions induced by bilereflux, in the absence of chemical carcinogens, in the rat remnantstomach to consist primarily of gastric type and secondarilyof intestinal type cells, and that they are reversible afterdiversion of bile reflux. The present study was designed toevaluate changes in proliferative activities in cells of eachtype under these conditions. The frequency of adenomatous hyperplasia(AH) induced in the gastric stump mucosa by duodenal contentreflux after Billroth II partial gastrectomy (BII) increaseduntil the 54th week of the experiment. Roux-en-Y (RY) surgicalprocedure which prevents duodenal reflux performed at the 24thor 36th week after BII led to a decrease in AH. Cell contentof the lesions was analyzed using routine H&E staining,immunohistochemical staining for pepsinogen isoenzyme 1 andhistochemical procedures for mucins (paradoxical concanavalinA, galactose oxidase Schiff and sialidase galactose oxidaseSchiff reactions) and proliferation in each compartment evaluatedby an immunohistochemical method using bromodeoxyuridine (BrdU)and a monoclonal antibody against BrdU. At the 54th week thenumber of BrdU-labeled cells per normal pyloric column was significantly(P < 0.05) increased to 10.63/pit after the BII operation,while it diminished to 5.23/pit after RY diversion, this beingthe same level as with the RY procedure alone. AH maintaineda high rate of BrdU incorporation at 12.7% after BII operation,which was also significantly reduced (P < 0.01) to 7.0% bythe RY surgery. The intestinal type cell showed highest (22.2%),the surface mucous type cell showed the next (16.5%) and thepyloric gland type cell showed lowest (5.2%) BrdU labeling indicesafter BII operation. All the cell types in AH showed similarproportional decreases in BrdU incorporation after RY diversion.Thus surgical intervention reverses the cell proliferation causedby bile reflux in the gastric stump. 相似文献
23.
Chlorhexidine susceptibility and Eagle effect in planktonic cells and biofilm of nosocomial isolates
Marchi Ana Paula Farrel Côrtes Marina Vásconez Noguera Saidy Rossi Flavia Levin Anna Sara Figueiredo Costa Silvia Perdigão Neto Lauro Vieira 《European journal of clinical microbiology & infectious diseases》2023,42(6):787-792
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to evaluate the chlorhexidine gluconate (CHG) susceptibility in both planktonic cells and biofilm of... 相似文献
24.
L. Rifas L. L. Dawson L. R. Halstead M. Roberts L. V. Avioli 《Calcified tissue international》1994,54(6):505-510
Human hypophosphatemic vitamin D-resistant rickets (X-linked hypophosphatemia-XLH) is characterized by hypophosphatemia, a decreased tubular reabsorption of phosphate (Pi) and defective skeleton mineralization. Utilizing a mouse model (Hyp) of XLH, which demonstrates biological abnormalities and skeletal defects of XLH, we analyzed sodium-dependent phosphate transport in isolated osteoblasts derived from the calvaria of normophosphatemic and hypophosphatemic mice. Initial rates of phosphate uptake by normal and Hyp osteoblasts showed similar slopes. Osteoblasts from both normal and Hyp mice exhibited saturable, sodium-dependent phosphate transport with apparent Vmax and Km values not significantly different (normal mice, Vmax=24.30±3.45 nmol/mg prot. 10 min, Km=349.49±95.20 mol/liter; Hyp mice, Vmax=23.03±3.41 nmol/mg prot. 10 min, Km=453.64±106.93 mol/liter, n=24). No differences were found in the ability of normal and Hyp osteoblasts to respond to Pi transport after 5 hours of Pi deprivation. Both cell types exhibited a similar increase in cAMP in response to PTH. The accumulated results demonstrate that Pi uptake and transport in normal and Hyp mouse osteoblasts is a sodium-dependent saturable process. As osteoblast Pi uptake and transport is apparently normal in the Hyp mouse model of XLH, the osteoblastic failure described for the Hyp mouse should be attributed to other mechanism(s). 相似文献
25.
Certain delivery systems are intended to release the active ingredient in different phases to obtain the desired therapeutic effect. For these formulations, such as a bilayer tablet, it is desirable to distinguish and measure the release of drug from the different phases simultaneously. Mass spectrometric methods were developed to measure three ibuprofen isotopomers in serum and two in dissolution fluid. The analytical methods were linear (r 0.992) over the concentration range of interest and recovery was greater than 99.2% for all isotopomers. Coadministration of [2H0]ibuprofen, [2H4]ibuprofen, and [2H7]ibuprofen to male beagles demonstrated that the isotopomers were bioequivalent and verified the absence of any kinetic isotope effect due to deuterium incorporation (p = 0.286). These methods were then used to evaluate a bilayer tablet formulation composed of an immediate release layer of 100 mg [2H4]ibuprofen and a sustained release layer with a drug load of 300 mg [2H0]ibuprofen. Two different rate-controlling polymer matrices that provided similar in vitro dissolution profiles were compared in the sustained release phase, while the immediate release formulation remained the same. In male beagles, the HPMC matrix delivered a significantly greater amount of ibuprofen (p < 0.05). The AUC was threefold greater for HPMC (1067 ± 437 nmole * h/ml) versus EUDRAGIT® (320 ± 51), and Cmax was nearly four times greater (145 ± 62.1 nmole/ml for HPMC versus 37.9 ± 14.4 for EUDRAGIT®). Although Tmax for HPMC (3.4 ± 1.9 h) lagged behind EUDRAGIT® (2.0 ± 0.82 h), the difference was not significant (p > 0.05). The immediate release layer was absorbed to the same extent as an oral solution (containing [2H7]ibuprofen) that was administered concomitantly with the bilayer tablet. Using the stable isotope markers also demonstrated that the release rates of the two layers were independent of each other, both in vivo and in vitro. Stable isotope techniques are a useful tool in the development of biphasic release formulations since they can be used to determine proper drug load of each phase as well as the appropriate rate of release. 相似文献
26.
Giustozzi GM Lucaroni E Lauro A Goracci GL Bartoli A Radicchi V Monacelli M Cirocchi R Bisacci C Moggi L 《Chirurgia italiana》1999,51(3):235-240
The aim of this randomized study was to determine the effects of octreotide therapy on the growth and development of experimental liver metastases from a human colonic cancer cell line (HT 29) in nude mice model. No important and significant difference could be found between mice, lungs and liver weights of both groups as well as lung metastatization; indeed, significant was the difference between groups concerning liver, metastases (the majority of them were in treated group): in spite of the small number of data collected, which does not allow to draw any conclusion on the efficacy of this drug on liver metastases, we believe that octreotide therapy does not affect dramatically the growth and development of liver metastases from a human colon cancer. 相似文献
27.
Feraco E Gallo R Grandinetti O Lauro A Madeo A 《Archives of gerontology and geriatrics》1996,23(3):293-298
Assessment of exercise capacity has been widely used in the evaluation of chronic heart failure (CHF), both to define the severity of the syndrome and to assess the changes induced by therapy. Various exercise tests and protocols can be used. The simple stress test using the exercise bicycle or the treadmill can give useful indications only in patients with severe or lower functional reductions. Maximum exercise duration usually depends on the patient's and the physician's motivation. The addition of respiratory gas exchange measurements, maximum oxygen consumption (VO(2)) or anaerobic threshold, increases the exactness of the assessment of the exercise limitation in CHF. VO(2) maximum provides an objective marker of aerobic capacity and it is biased by neither the patient nor the physician. This technique, however, requires the patient to exercise to exhaustion, and it is somewhat subjective and not indicative of normal daily exercise routine. The anaerobic threshold is a useful way of evaluating adaptability to submaximal efforts and the impact of the therapy on the daily performance. Nevertheless, it is significantly influenced by the fitness level and it has a reduced prognostic capability compared to VO(2) maximum. Submaximal exercise tests discriminate particularly between patients with severe CHF. The major limits are the influence of the patient's motivation and its limited validation in terms of reproducibility and prediction in controlled surveys. 相似文献
28.
Silei V Fabrizi C Venturini G Tagliavini F Salmona M Bugiani O Lauro GM 《Brain research. Brain research protocols》2000,5(2):132-134
The fluorescent calcium-sensitive indicators, such as the Calcium Green-1, allow one to detect small calcium transients at low indicator concentrations. The protocol reported here is a rapid and sensitive method that facilitates the measurement of intracellular free-calcium in cell suspensions. Using this assay, we were able to detect and quantify the variations in intracellular calcium concentration during microglial cell activation induced by the fragment peptides beta25-35 and PrP106-126. 相似文献
29.
Epirubicin, cisplatin and docetaxel combination therapy for metastatic gastric cancer. 总被引:1,自引:0,他引:1
L Di Lauro F Belli M G Arena S Carpano G Paoletti D Giannarelli M Lopez 《Annals of oncology》2005,16(9):1498-1502
BACKGROUND: Docetaxel is a new agent with activity in metastatic gastric cancer. This phase II study was designed to evaluate the activity and safety of an epirubicin, cisplatin and docetaxel combination in patients with this disease. PATIENTS AND METHODS: Forty-six patients with gastric adenocarcinoma with measurable distant metastasis were eligible for the study. Patients received epirubicin 50 mg/m(2) and docetaxel 60 mg/m(2), on day 1, and cisplatin 60 mg/m(2) on day 2. Granulocyte colony-stimulating factor 300 mug/day subcutaneously was given on days 5 and 6. Cycles were repeated every 3 weeks for a maximum of eight courses. RESULTS: All patients were evaluable for response and toxicity. Two complete and 21 partial responses were observed, with an overall response rate of 50% [95% confidence interval (CI) 36% to 64%]. Stable disease was observed in 13 patients (28%) and progressive disease in 10 patients (22%). The median time to progression was 6 months (95% CI 5-7) and the median overall survival was 11.2 months (95% CI 8.5-13.9). Grade 3/4 neutropenia, thrombocytopenia and anemia occurred in 46%, 7% and 13% of patients, respectively. There were five episodes of febrile neutropenia in four patients. Other grade 3 toxicities included mucositis in three patients (6.5%), vomiting in four patients (8.7%) and diarrhea in one patient (2%). There were no cardiac toxicity, severe neurotoxicity or treatment-related deaths. CONCLUSIONS: The epirubicin, cisplatin and docetaxel combination is an active and well tolerated novel chemotherapy regimen for treating metastatic gastric cancer and deserves further evaluation in randomized studies. 相似文献
30.
The in vitro reduction of zearalenone (ZEN) by subcellular fractions from hen and rabbit hepatocytes clearly shows species-specific differences in the cofactor requirements, rate of metabolism and production of metabolites. The presence of NADH as cofactor in the reaction mixtures enhanced only the reducing activity of the microsomal fraction from rabbit hepatocytes, while NADPH enhanced the reducing activities of the cytosolic fraction from rabbit and both the microsomal and cytosolic fractions from hen hepatocytes. Furthermore, we observed that hen hepatocytes metabolize faster and produce beta-zearalenol (ZEL) as the major metabolite, whereas rabbit hepatocytes metabolize ZEN slowly and mainly into alpha-ZEL, the more uterotrophic metabolite. These last findings are closely related to the higher sensitivity to ZEN estrogenic effects observed in rabbits during the toxicity test involving p.o. administration of the mycotoxin to the animals at 3 dosage levels (0.1, 1, 2 mg/kg body wt). 相似文献