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61.
De Paola F Ridolfi R Riccobon A Flamini E Barzanti F Granato AM Mordenti GL Medri L Vitali P Amadori D 《British journal of cancer》2003,88(2):320-326
We investigated the effects of interleukin-2 (IL-2) exposure on T-cell signal transduction molecules and apoptosis markers in tumour-infiltrating lymphocytes (TIL) isolated from 20 melanoma and 16 colorectal carcinoma metastases and expanded in vitro for therapeutic reinfusion. Before IL-2 culture, TIL showed undetectable or very low levels of T-cell receptor (TCR) epsilon chain, p56(lck), Fas ligand (FasL) and Bax expression, while Bcl-2 values were elevated. Cancer cells were characterised by low or absent Fas and Bcl-2 and high Bax expression. Notably, they also expressed FasL. After 41-48 days of IL-2 culture, TCR epsilon chain and p56(lck) expression of TIL rose to median values of approximately 80 and 30% positive cells, respectively (P<0.001), FasL expression was detected in 45% cells from melanomas (P<0.001) and in 3% from colorectal carcinomas (P=0.09), and Bax-positive cells increased from 17.5 to 70% (P=0.005). Moreover, TCR zeta chain-positive cells were significantly increased from baseline (P=0.001), Bcl-2-positive cells dropped from 50 to 1% (P=0.007) and perforin content was high, while Fas expression was not significantly modified by IL-2 culture. In conclusion, our data suggest that the degree of immunosuppression in TIL from melanomas and colorectal carcinomas is very high, and the apoptosis markers' repertoire of cancer cells resembles that of immune-privileged tissue. Interleukin-2 culture appears to restore lymphocyte activation mechanisms, resulting in consistent FasL expression and perforin production. 相似文献
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Different antiseptic formulations have shown limitations when applied to disinfecting intact skin, notably short-term tolerability and/or efficacy. The purpose of this study was optimizing a new antiseptic formulation specifically targeted at intact skin disinfection and evaluating its in vitro microbicidal activity and in vivo efficacy. METHODS: The biocidal properties of the antiseptic solution containing 0.5% chloramine-T diluted in 50% isopropyl alcohol (Cloral; Eurospital SpA Trieste, Italy) were measured in vitro versus gram-positive-, gram-negative-, and acid-alcohol-resistant germs and fungi with standard suspension tests in the presence of fetal bovine serum. Virus-inhibiting activity was evaluated in vitro against human cytomegalovirus, herpes simplex virus, poliovirus, hepatitis B virus, and hepatitis C virus. Tests used different methods for the different biologic and in vitro replication capacity of these human viruses. Lastly, Cloral tolerability and skin colonization retardation efficacy after disinfection were studied in vivo. RESULTS: The antiseptic under review showed fast and sustained antimicrobial activity. The efficacy of Cloral against clinically important bacterial and viral pathogens and fungi was highlighted under the experimental conditions described in this article. Finally, microbial regrowth lag and no side effects were documented in vivo after disinfection of 11 volunteers. CONCLUSIONS: A stable chloramine-T solution in isopropyl alcohol may be suggested for intact skin antisepsis. 相似文献
63.
Effects of a methanolic extract and a hyperforin-enriched CO2 extract of Hypericum perforatum on alcohol intake in rats 总被引:1,自引:0,他引:1
Perfumi M Panocka I Ciccocioppo R Vitali D Froldi R Massi M 《Alcohol and alcoholism (Oxford, Oxfordshire)》2001,36(3):199-206
Hypericum perforatum extracts (HPE) inhibit ethanol intake in rats. Hypericin and hyperforin have been proposed as major active principles of HPE. The present study compared the effect on ethanol intake in alcohol-preferring rats of two Hypericum perforatum extracts: a methanolic extract containing 0.3% hypericin and 3.8% hyperforin (HPE1) and a CO2 extract (HPE2) with 24.33% hyperforin and very low hypericin content. Freely feeding and drinking rats were offered 10% ethanol 2 h/day and HPE were given intragastrically 1 h before access to ethanol. Both extracts dose-dependently reduced ethanol intake, HPE2 being about eight times more potent than HPE1. Food and water intakes were not affected by doses that reduced ethanol intake. HPE2, unlike HPE1, reduced blood-alcohol levels (BAL) at doses of > or = 31.2 mg/kg, whereas the dose of 15.6 mg/kg, which reduced ethanol intake, did not significantly modify BAL; blood-acetaldehyde levels were never increased. As previously observed for HPE1, intracerebroventricular pretreatment with 5,7-dihydroxytryptamine (150 microg/rat) did not affect attenuation of ethanol intake induced by HPE2, but reduced its effect in the forced swimming test (FST). Intraperitoneal pretreatment with the sigma-1 receptor antagonist NE-100 (0.25 mg/kg) did not affect inhibition of ethanol intake induced by HPE1 (250 mg/kg) or HPE2 (125 mg/kg), but abolished the effect of both extracts in the FST. In conclusion, the present results indicate that HPE2 inhibits ethanol intake more potently than HPE1; the higher potency of HPE2 parallels the hyperforin content, suggesting that hyperforin may have an important role in reducing ethanol intake. Moreover, different neurochemical mechanisms are apparently responsible for the reduction of ethanol intake and for the antidepressant-like effect of HPE. 相似文献
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Jacob Kurniawan Ram P. Maharjan Wai-Fong Chan Peter R. Reeves Vitali Sintchenko Gwendolyn L. Gilbert Frits R. Mooi Ruiting Lan 《Emerging infectious diseases》2010,16(2):297-300
Multilocus variable-number tandem-repeat analysis (MLVA) of 316 Bordetella pertussis isolates collected over 40 years from Australia and 3 other continents identified 66 MLVA types (MTs), including 6 predominant MTs. Typing of genes encoding acellular vaccine antigens showed changes that may be vaccine driven in 2 MTs prevalent in Australia. 相似文献
67.
Massimiliano Vitali Eliana Venturelli Daniela Galimberti Luisa Benerini Gatta Elio Scarpini Dario Finazzi 《Journal of neural transmission (Vienna, Austria : 1996)》2009,116(12):1635-1641
Decay of mitochondria and oxidative stress are associated with normal aging, but many neurodegenerative diseases, and particularly
Alzheimer’s disease (AD), are characterized by a significant increase in the intensity of these traits. Recent data suggest
the possible contribution of heme deficiency to the progressive derangement of mitochondria in AD brain; shortage of heme,
and particularly of heme-a, actually leads to loss of mitochondrial cytochrome c oxidase (COX), abnormal production of reactive oxygen species and altered amyloid precursor protein metabolism. We reasoned
that differences in the amount and/or functioning of COX assembly subunit 10 (COX10) and 15 (COX15), the key enzymes involved
in heme-a biosynthesis, could be linked to variations of the individual risk to develop AD. We analyzed their mRNA expression
in the hippocampus from AD patients and controls, investigated the existence of nucleotide variations in their DNA sequences
and analyzed their distribution in large groups of AD and control individuals. COX 15 mRNA was significantly more abundant
in the cerebral tissue of AD patients (3.18 ± 1.70 vs. 1.22 ± 0.66 μg, normalized dose, P = 0.01). The IVS-178G>A SNP in COX10 and the c+1120C>T SNP in COX15 were significantly less represented in the patient group
(P < 0.001 and P = 0.017, respectively) with respective odd ratios of 0.22 and 0.59, suggesting a possible protective role toward the risk
for AD. 相似文献
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Effects of two central antimuscarinic drugs, namely N-methyl-4-piperidinol benzylate and tropine phenylcyclopentylglycolate on Na currents in internally dialyzed mouse neuroblastoma cells were studied using the suction-pipette voltage-clamp technique. Like amine local anesthetics, the both compounds produce two phenomenologically different types of sodium current inhibition: a steady block without conditioning and a cumulative (use-dependent) block which develops during repetitive membrane pulsing. The ability of these m-cholinoblockers to modulate voltage-dependent ionic permeability of the neuronal membranes is supposed to be one of possible components in the mechanism of their both main and accessory (non-synaptic) effects. 相似文献