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991.
Regoli F Frenzilli G Bocchetti R Annarumma F Scarcelli V Fattorini D Nigro M 《Aquatic toxicology (Amsterdam, Netherlands)》2004,68(2):167-178
Harbours can be considered as model environments for developing and validating field monitoring procedures and to investigate mechanistic relationships between different biological responses. In this study, several biomarkers were investigated in marine mussels caged for 4 weeks into an industrialised harbour of north-west Italy. Organisms were collected at different time intervals to better characterise the sensitivity, temporal variations and interactions of analysed responses. Besides single antioxidants (catalase, glutathione S-transferases, glutathione reductase, total glutathione), the total oxyradical scavenging capacity (TOSC) assay was used to analyse the capability of the whole antioxidant system to neutralise specific forms of radicals: these data were further integrated by measurement of DNA integrity, oxidised bases and the impairment of lysosomal membrane stability in haemocytes. Results showed a biphasic trend for single antioxidants and TOSC, with no variation or increase during the first 2 weeks of exposure to the polluted site followed by a progressive decrease up to a severe depletion in the final part of the experiment. These findings suggest an initial counteractive response of mussels toward the enhanced prooxidant challenge, while antioxidants appeared overwhelmed at longer exposure periods. The hypothesis of reactive oxygen species (ROS) mediated toxicity is supported by the appearance of cell damages (DNA integrity and lysosome membrane stability), which exhibited a progressive enhancement during the course of the experiment with a maximum impairment after 30 days of exposure. 相似文献
992.
993.
Livio?GarattiniEmail author Francesca?Chiaffarino Dante?Cornago Carlo?Coscelli Fabio?Parazzini 《The European journal of health economics》2004,5(1):15-21
This study estimated the resource utilization and direct medical costs in Italian diabetes centers (DCs). Hospital admissions for major chronic complications were not considered since DCs deliver primary care and follow up only complications unequivocally related to diabetes-acute complications and diabetic foot. The multicenter, prospective, observational study involving 31 Italian DCs included a total of 1,910 patients classified into eight prognostic groups by type of diabetes (types 1 and 2), metabolic control (HbA1c >7.5%, HbA1c 7.5%) and age (60, >60). The average total cost of type 1 diabetes per patient per year ranged from € 762 in group 2 (age 60, HbA1c >7.5%) to € 1,060 in group 4 (age >60, HbA1c >7.5%), and that the cost of type 2 diabetes from € 423 in group 5 (age 60, HbA1c 7.5%) to € 613 in group 8 (age >60, HbA1c >7.5%). The study brought to light the wide variability in the single cost components across clinically defined groups of patients. The cost of diabetes management in the strict sense was significantly affected by the type of diabetes and metabolic control.Data monitoring: E. Negri.E. Ansaldi, Alessandria; C. Baggiore, Florence; M. Balsanelli, Ostia; C. Bertoni, La Spezia; V. Borzì, Catania; A. Boscolo Bariga, Chioggia; A. Bruno, Turin; S. Caronna, Parma; F. Chiaromonte, Rome; S. Ciaccio, Pisa; G. Cicioni, Terni; M. Di Mauro, Catania; S. Gamba, Turin; L. Gentile, Asti; S. Giannini, Florence; D. Giorgi Pierfranceschi, Piacenza; T. Lavagnini, Padua; M. Lunetta, Catania; M. Marchesi, Bolzano; I. Meloncelli, San Benedetto del Tronto (Ascoli Piceno); G. Micali, Messina; M. Orrasch, Treviso; C. Pacchioni, Modena; M. Parillo, Caserta; G. Perriello, Perugia; S. Pistone, Potenza; G. Rinaldi, Naples; G. Sessa, Naples; M. Tagliaferri, Larino; P. Tatti, Marino (Rome); P. Ubaldi, Genua; M. Velussi, Monfalcone (Triest); E. Vitacolonna, Pescara; G. Zoppini, Verona; P. Zucchi, Asola (Mantua). 相似文献
994.
Simonelli F Testa F Zernant J Nesti A Rossi S Rinaldi E Allikmets R 《Ophthalmic research》2004,36(2):82-88
Genetic variation in the ABCA4 (ABCR) gene has been associated with several distinct retinal phenotypes, including Stargardt disease/fundus flavimaculatus (STGD/FFM), cone-rod dystrophy (CRD), retinitis pigmentosa (RP) and age-related macular degeneration. The current model of genotype/phenotype association suggests that patients harboring deleterious mutations in both ABCR alleles would develop RP-like retinal pathology. Here we describe ABCA4-associated phenotypes, including a proband with a homozygous nonsense mutation in a family from Southern Italy. The proband had been originally diagnosed with STGD. Ophthalmologic examination included kinetic perimetry, electrophysiological studies and fluorescein angiography. DNA of the affected individual and family members was analyzed for variants in all 50 exons of the ABCA4 gene by screening on the ABCR400 microarray. A homozygous nonsense mutation 2971G>T (G991X) was detected in a patient initially diagnosed with STGD based on funduscopic evidence, including bull's eye depigmentation of the fovea and flecks at the posterior pole extending to the mid-peripheral retina. Since this novel nucleotide substitution results in a truncated, nonfunctional, ABCA4 protein, the patient was examined in-depth for the severity of the disease phenotype. Indeed, subsequent electrophysiological studies determined severely reduced cone amplitude as compared to the rod amplitude, suggesting the diagnosis of CRD. ABCR400 microarray is an efficient tool for determining causal genetic variation, including new mutations. A homozygous protein-truncating mutation in ABCA4 can cause a phenotype ranging from STGD to CRD as diagnosed at an early stage of the disease. Only a combination of comprehensive genotype/phenotype correlation studies will determine the proper diagnosis and prognosis of ABCA4-associated pathology. 相似文献
995.
Syphilitic interstitial keratitis: treatment with immunosuppressive drug combination therapy 总被引:1,自引:0,他引:1
OBJECTIVE: The following is a case presentation of congenital syphilitic keratitis in a boy 6 years of age who was successfully treated with an immunosuppressive drug combination therapy. METHODS: Congenital syphilitic keratitis was diagnosed by clinical findings and laboratory tests. The child was unresponsive to traditional treatment; thus, systemic immunosuppressive therapy, which consisted of oral cyclosporine 4 mg/kg/d, 6 days per week, and oral low-dose steroids (fluocortolone 0.8 mg/kg a week, given every other day), was initiated. RESULTS: Corneal disease showed great improvement with this therapy, with progressive healing of lesions in the first month of treatment and no signs of toxic renal, hepatic, or growth abnormalities. Recurrences of uveitis have not occurred, and corneal interstitial keratitis episodes have been limited to 3 in an 8-year period. After 6 months with no recurrences, a tapering off of the systemic therapy was initiated, and the child is still asymptomatic and without flare-ups. CONCLUSIONS: Congenital syphilitic keratitis is usually treated with topical steroids and cycloplegic drugs, which not only can be ineffective but can also lead to complications such as cataract and glaucoma. In the present case report, a pediatric patient affected by syphilitic interstitial keratitis was treated successfully with an immunosuppressive drug combination therapy. 相似文献
996.
The coexistence of nicotinic cholinergic receptors (nAChRs) and of N-methyl-D-aspartate (NMDA) receptors on the same noradrenergic axon terminals and the nAChR/NMDA receptor cross-talk were investigated by monitoring the release of noradrenaline (NA) evoked in superfused rat hippocampal synaptosomes by (-)-nicotine and NMDA alone or in combination. In medium containing a physiological concentration (1.2 mM) of Mg2+, the release of [3H]NA was very slightly increased by NMDA plus glycine, whereas it was significantly enhanced by (-)-nicotine. The (-)-nicotine/NMDA combination elicited supraadditive release which was totally abolished by the nAChR blocker mecamylamine and partly prevented by selectively blocking NMDA receptors. Supraadditive [3H]NA release was also observed by exposing synaptosomes to veratrine, but not to ionomycin. The supraadditive release elicited by the (-)-nicotine/NMDA or the veratrine/NMDA combination was sensitive to the protein kinase A/C inhibitor staurosporine and the selective protein kinase A inhibitor H89, but insensitive to the protein kinase C inhibitor Ro 31-8220. It is concluded that (i) release-modulating nAChRs and NMDA receptors coexist on hippocampal noradrenergic axon terminals; and (ii) nicotine permits NMDA receptor activation in the presence of Mg2+, possibly because the nicotine-induced influx of Na+ depolarizes the nerve ending membrane sufficiently to remove the Mg2+ block. 相似文献
997.
Sale A Putignano E Cancedda L Landi S Cirulli F Berardi N Maffei L 《Neuropharmacology》2004,47(5):649-660
Rearing mice from birth in an enriched environment leads to a conspicuous acceleration of visual system development appreciable at behavioral, electrophysiological and molecular level. Little is known about the possible mechanisms of action through which enriched environment affects visual system development. It has been suggested that differences in maternal behavior between enriched and non-enriched conditions could contribute to the earliest effects of enriched environment on visual development and that neurotrophins, BDNF in particular, might be involved. Here, we examined Brain Derived Neurotrophic Factor (BDNF) levels in the visual cortex during development and showed that an increase occurs in the first week of life in enriched pups compared to standard reared pups; BDNF levels at birth were equal in the two groups. This suggests a postnatal rather than a prenatal effect of environment on BDNF. A detailed analysis of maternal care behavior showed that pups raised in a condition of social and physical enrichment experienced higher levels of licking behavior and physical contact compared to standard reared pups and that enhanced levels of licking were also provided to pups in an enriched environment where no adult females other than the mother were present. Thus, different levels of maternal care in different environmental conditions could act as indirect mediator for the earliest effects of enrichment on visual system development. Some of the effects of different levels of maternal care on the offspring behavior are long lasting. We measured the visual acuity of differentially reared mice at the end of the period of visual acuity development (postnatal day 45) and at 12 months of age, using a behavioral discrimination task. We found better learning abilities and higher visual acuity in enriched compared to standard reared mice at both ages. 相似文献
998.
Parazzini F Chiaffarino F Polverino G Chiantera V Surace M La Vecchia C 《European journal of epidemiology》2004,19(3):249-253
To understand the role of several medical conditions on the risk of uterine fibroids, we analysed the findings of a large case-control study. Cases were 843 women aged 54 or less (median age 43 years, range 21-54) with histologically confirmed uterine fibroids, whose clinical diagnosis dated back no more than 2 years. Indications for surgery were recurrent menorrhagia or ultrasound evidence of fibroids larger than 10 cm in diameter. Controls were 1557 women aged 54 years or less of comparable quinquennia of age (median age 43 years, range 21-54) who had not undergone hysterectomy and were admitted for acute, non-gynecologic, non-hormonal, non-neoplastic conditions to a network of hospitals with a similar catchment area. Clinical history of severe overweight was inversely associated with the risk of fibroids (multivariate odds ratio (OR), OR: 0.6, 95% confidence intervals (CI): 0.5-0.8). An increase in the frequency of fibroids was seen in women with a history of benign breast disease (OR: 1.2, 95% CI: 0.9-1.6) and particularly of breast biopsies (OR: 2.0, 95% CI: 1.2-3.5). The results of this large dataset indicate that medical conditions known or likely to be related to female hormones are not important determinants of the risk of fibroids. 相似文献
999.
Nano R Barni S Chiari P Pinelli T Fossati F Altieri S Zonta C Prati U Roveda L Zonta A 《Oncology reports》2004,11(1):149-153
The effect of neutron boron capture therapy (BNCT) was studied in rat tumor liver cells after induction of the liver metastases by splenic inoculation of cells from DHA/K12/TRb line. Ten days following the treatment, the BPA was injected into rats and therefore the animals were sacrificed, the liver was exposed to neutron irradiation and processed. In some experiments the liver was reimplanted (after irradiation) in syngenic animals and studied 3 days later, following sacrifice. Samples of tissue obtained from metastasised and non-metastasised areas of the liver parenchyma, before and after the neutron irradiation, were examined in light microscopy and electron microscopy. The analysis pointed out damages induced by the neutron treatment in single tumor cells mostly localised in the synusoidal blood stream. Debris and apoptotic cells were sometimes observed in the neoplastic nodules before treatment, while the tumor cell death (apoptosis) increased in the tumor cells following BNCT treatment. An intense scavenger activity of Kupffer cells after irradiation was accompanied by a strong acid phosphatase reaction detectable in wide cytoplasmic areas. In the liver parenchyma of reimplanted animals, the presence of large collagen bundles spread among the hepatocytes was observed at electron microscopy. 相似文献
1000.
Donato G Martinez Hoyos J Amorosi A Maltese L Lavano A Volpentesta G Signorelli F Pentimalli F Pallante P Ferraro G Tucci L Signorelli CD Viglietto G Fusco A 《Oncology reports》2004,11(6):1209-1213
Glioblastoma is one of the most aggressive tumors in mankind with 50% of patients dying within the 1st year of diagnosis, and being refractory to conventional therapies. The aim of our work has been to analyse the expression of the HMGA1 proteins in human astrocytomas and glioblastomas in order to verify whether the detection of these proteins might be of some help in the diagnosis of these neoplasias. Here we report the analysis of 27 cases, including 12 astrocytomas and 15 glioblastomas, for HMGA1 expression. All the neoplastic samples showed positive staining even though the number of positive cells and the staining intensity was higher in glioblastomas compared to astrocytomas. Conversely, HMGA1 proteins were not detected in normal brain. Accordingly, expression of the hmga1 gene, analysed by RT-PCR, was higher in glioblastomas than in astrocytomas. 相似文献