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951.
Torrente Y Belicchi M Pisati F Pagano SF Fortunato F Sironi M D'Angelo MG Parati EA Scarlato G Bresolin N 《Cell transplantation》2002,11(1):25-34
Stem cell populations have been shown to be extremely versatile: they can generate differentiated cells specific to the tissue in which they reside and descendents that are of different germ layer origin. This raises the possibility of obtaining neuronal cells from new biological source of the same adult human subjects. In this study, we found that epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) cooperated to induce the proliferation, self-renewal, and expansion of neural stem cell-like population isolated from several newborn and adult mouse tissues: muscle and hematopoietic tissues. This population, in both primary culture and secondary expanded clones, formed spheres of undifferentiated cells that were induced to differentiate into neurons, astrocytes, and oligodendrocytes. Brain engraftment of the somatic-derived neural stem cells generated neuronal phenotypes, demonstrating the great plasticity of these cells with potential clinical application. 相似文献
952.
Miglior S Zeyen T Pfeiffer N Cunha-Vaz J Torri V Adamsons I;European Glaucoma Prevention Study Group 《Ophthalmology》2002,109(9):1612-1621
OBJECTIVES: The European Glaucoma Prevention Study seeks to evaluate the efficacy of reducing intraocular pressure (IOP), with dorzolamide to prevent or delay patients affected by ocular hypertension from developing primary open-angle glaucoma. DESIGN: Randomized, double-blinded, controlled clinical trial. PARTICIPANTS: Patients (age > or =30 years) were enrolled from 18 European centers. The patients fulfilled a series of inclusion criteria including the measurements of IOP (22-29 mmHg), two normal and reliable visual fields (VFs) (on the basis of mean defect and corrected pattern standard deviation/corrected loss of variance of standard 30/II Humphrey or Octopus perimetry), and normal optic disc as determined by the Optic Disc Reading Center (vertical and horizontal cup-to-disc ratios; asymmetry between the two eyes < or =0.4). INTERVENTION: Patients were randomized to the treatment with dorzolamide or a placebo. MAIN OUTCOME MEASURES: End points are VF and/or optic disc changes. A VF change during the follow-up must be confirmed by two further positive tests. Optic disc change is defined by the agreement of two out of three independent observers evaluating optic disc stereo-slides. RESULTS: One thousand seventy-seven subjects were randomized between January 1, 1997 and May 31, 1999. The mean age was 57.03 +/- 10.3 years; 54.41% were women and 99.9% were Caucasian. Mean IOP was 23.6 +/- 1.6 mmHg in both eyes. Mean visual acuity was 0.97 +/- 0.11 in both eyes; mean refraction was 0.23 +/- 1.76 diopters in the right eye and 0.18 +/- 1.79 diopters in the left eye. Previous use of medication for ocular hypertension was reported by 38.4% of the patients, systemic hypertension by 28.1%, cardiovascular diseases by 12.9%, and diabetes mellitus by 4.7%. The qualifying VFs were normal and reliable according to protocol criteria. CONCLUSIONS: The mean IOP of the patients enrolled in the European Glaucoma Prevention Study is consistent with the estimated mean IOP (within the range of 22-29 mmHg) found in a large sample of the European population. The European Glaucoma Prevention Study should be able to better address the clinical question of whether pharmacological reduction of IOP (by means of dorzolamide) in ocular hypertension patients at moderate risk for developing primary open-angle glaucoma effectively lowers the incidence of primary open-angle glaucoma. 相似文献
953.
954.
Smokers deprived of cigarettes for 72 h: effect of nicotine patches on craving and withdrawal 总被引:3,自引:3,他引:0
Abstract
Rationale. Research on the effects of nicotine abstinence and nicotine replacement has not provided consistent information about the
impact of replacement therapies on tobacco withdrawal and craving.
Objective. This study investigated craving and withdrawal symptoms over a 72-h period of abstinence from cigarettes.
Methods. Twenty-four healthy volunteers, not intending to quit smoking, were housed in an experimental unit during three 72-h conditions,
consisting of either free smoking, enforced smoking cessation with nicotine replacement therapy (NRT) patches, or enforced
smoking cessation with placebo patches. The conditions were adhered to using a randomized crossover design, each separated
by at least 10 days of washout. Patches, administered in a double-blind fashion, were given as nicotine (21 mg/24 h) and placebo
every 24 h. Self-reported cigarette craving and withdrawal were assessed using multi-item scales at fixed intervals over each
condition period. Urinary and plasma cortisol levels were also assayed at fixed intervals over each period.
Results. Craving intensity was significantly lower with free smoke than with placebo and with NRT patches than with placebo. No difference
in craving levels was found between those who smoked or those who had NRT patches. Withdrawal symptoms were significantly
lower with free smoke than with either placebo or NRT patches, but there was no difference in levels of withdrawal between
those on NRT patches and those on placebo. During the placebo and NRT patch periods, craving intensity displayed a circadian
rhythm, with craving levels lowest in the morning and peaking in the evening. Nicotine delivered via the patch had no impact
on these circadian variations in craving. There was no evidence of systematic temporal variations in craving levels during
the free smoking period.
Conclusions. The data suggested that craving and withdrawal symptoms may be sustained by different physiological pathways, and that only
selected components of cigarette craving are influenced by NRT.
Electronic Publication 相似文献
955.
Genotype- and experience-dependent susceptibility to depressive-like responses in the forced-swimming test 总被引:4,自引:0,他引:4
Abstract
Rationale. The forced-swimming test (FST) is utilized to reproduce passive coping responses to stress that may model a relevant aspect
of human depression in rodent species. Animals showing high levels of passive responses to the FST are assumed to model pathologically
depressed individuals.
Objectives. We evaluated sensitivity of FST-induced behavioral responses to the interaction between genetic and environmental influences.
Methods. Behavioral responses to FST were evaluated in naive mice of the C57BL/6 and DBA/2 strains, in mice of both strains pre-exposed
to FST 14 days before test, and in FST-experienced animals subsequently exposed to 12 days of stress experience (food restriction).
Results. C57BL/6 mice are characterized by high propensity to adopt passive coping responses in the FST. Moreover, stress enhances
FST-induced immobility in mice of the C57BL/6 strain but reduces this response in DBA/2 mice. Finally, FST-induced immobility
in C57BL/6 mice is reduced by chronic treatment with clinically effective antidepressants.
Conclusions. These results support the view that behavioral and neural responses to FST exhibited by C57BL/6 mice can be usefully exploited
by pre-clinical research on depression.
Electronic Publication 相似文献
956.
957.
Occupational risk factors for renal cell cancer: a case--control study in northern Italy 总被引:1,自引:0,他引:1
Mattioli S Truffelli D Baldasseroni A Risi A Marchesini B Giacomini C Bacchini P Violante FS Buiatti E 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》2002,44(11):1028-1036
Relatively little is known about occupational and other risk factors for renal-cell carcinoma (RCC). Associations between RCC and occupations, exposures and other factors were investigated in a hospital-based case-control study in Bologna (central-northern Italy). Between 1986 and 1994, 324 histologically confirmed RCC cases were diagnosed at Policlinico S. Orsola-Malpighi in patients from the Province of Bologna. Corresponding control subjects admitted to the same hospital with any diagnosis except RCC were matched for sex, age, and residency. We studied the 249 cases and 238 controls for whom detailed information on occupational history, diet, smoking habits, alcohol and drug intake was obtained. At conditional logistic regression, among males (167 matched pairs), significant matched odds ratios (OR) were found, after adjusting for cigarette smoking and alcohol intake, for high body-mass index BMI (third quartile: OR, 4.91; confidence interval [95% CI], 1.56-15.5; last quartile: OR, 4.42; 95% CI, 1.48-13.18), railway workers (OR, 10.14; 95% CI, 1.46-70.17) and asbestos exposure (OR, 7.11; 95% CI, 1.46-34.51); nearly significant OR were found for managers (OR, 3.59; 95% CI, 0.82-15.59) and metal workers (OR, 2.21; 95% CI, 0.99-5.37). Among females (52 pairs), significant OR were found for BMI > 25.4 (OR, 8.46; 95% CI, 1.02-68.0). Railway workers (on or near to trains) may have increased risk of developing RCC, possibly due to asbestos exposure. Studies are required on possible risks encountered by railway (and metal) workers and by managers. 相似文献
958.
The present paper focuses on the Italian registries: their actual achievements, future developments and the possible critical states. The present setting is analysed in perspective with the international and European framework of cancer registries. Given the recent development of new cancer registries in Italy, and their participation to traditional and new international publication of their data, there is an increasing delay in publication time, both in Italy and abroad International and national institutions played an important role in helping and supporting registries' development, but delays in publications and some uncertainty in coordinating incidence and survival analyses in a unique framework is posing an unavoidable challenge. 相似文献
959.
Ottaná R Mazzon E Dugo L Monforte F Maccari R Sautebin L De Luca G Vigorita MG Alcaro S Ortuso F Caputi AP Cuzzocrea S 《European journal of pharmacology》2002,448(1):71-80
Within the series of chiral 3,3'-(1,2-ethanediyl)bis[2-arylthiazolidin-4-ones], the 3,4-dimethoxyphenyl substituted derivative was found in the primary anti-inflammatory screening to be endowed with superior in vivo properties and good safety profile. Such a lead compound was modified by eliminating 3-methoxy group while retaining 4-methoxy group on the aryl rings at 2 and 2' stereogenic carbons. The 2R,2'S-meso isomer (VIG3b) of the resulting bisthiazolidinone has been widely investigated. The inhibitory effects on cyclo-oxygenase-1 and cyclo-oxygenase-2 isoenzymes were measured in a human whole blood assay. VIG3b was almost 50 times more selective on the inducible isoform. The cyclo-oxygenase-2 preferential selectivity has been confirmed by modeling VIG3b into the cyclo-oxygenase-1 and cyclo-oxygenase-2 active sites. Furthermore, VIG3b was assayed in the experimental model of carrageenan-induced lung injury by evaluating its ability to inhibit: (1) fluid accumulation in the pleural cavity, (2) neutrophil infiltration, (3) prostaglandin E(2) production and (4) lung injury. VIG3b exhibited interesting activity in all these tests. 相似文献
960.
Adenosine modulates several physiological functions in the CNS and in peripheral tissues via membrane receptors which have been classified into four adenosine subtypes. A(1) activation produces neuronal depression: this inhibition allows A(1) agonists to produce ischemic tolerance and protection in neuronal tissue. In order to selectively reproduce these effects, several A(1) selective ligands have been synthesised and evaluated to understand how they interact with the adenosine A(1) receptor. The investigation methods include SAR studies using native and chemically modified A(1) receptors, molecular cloning of native and mutant adenosine A(1) receptors, molecular modeling and thermodynamic analysis of drug-receptor interaction. Despite the great quantity of information available on the adenosine A(1) receptor, no A(1) agonist has so far entered in clinical use against brain diseases in view of the side effects; moreover selective A(1) agonists appear to be poorly adsorbed into the brain and can be quickly degraded in vivo or in the whole blood. In an attempt to overcome these problems studies have been undertaken dealing with the use of partial agonists to inhibit side-effects and the employment of prodrugs to increase stability and diffusion through lipid barriers of A(1) ligands. Other attempts involve either the use of A(1) receptor enhancers as modulators able to locally enhance the action of endogenously produced adenosine, or the encapsulation of A(1)agonists in drug delivery systems targeted to the brain. In this review, these approaches will be described together with the effects of adenosine A(1) receptor ligands and their binding mechanisms on the central nervous system. 相似文献