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981.
Rango M Arighi A Biondetti P Barberis B Bonifati C Blandini F Pacchetti C Martignoni E Bresolin N Nappi G 《Functional neurology》2007,22(2):75-79
This paper looks at the use of magnetic resonance spectroscopy (MRS) for diagnostic and research purposes in Parkinson's disease and parkinsonian syndromes. The review considers both proton MRS (1H MRS) and phosphorus MRS (31 P MRS) studies. MRS is useful for diagnostic purposes, helping to differentiate Parkinson's disease from other parkinsonian syndromes. Even more usefully, MRS can be used for non invasive in vivo human research. 相似文献
982.
Daniela Cocchi Alessandra Colciago Francesca Pagani Tiziana Rubino Patrizia Bonfanti Fabio Celotti 《Toxicology and applied pharmacology》2009,237(2):127-165
Polychlorinated biphenyls (PCBs) are pollutants detected in animal tissues and breast milk. The experiments described in the present paper were aimed at evaluating whether the four PCB congeners most abundant in animal tissues (PCB-138, -153, -180 and -126), administered since fetal life till weaning, can induce long-term alterations of GH-axis activity and bone mass in the adult rat. We measured PCB accumulation in rat brain and liver, somatic growth, pituitary GH expression and plasma hormone concentrations at different ages. Finally, we studied hypothalamic somatostatin expression and bone structure in adulthood, following long-term PCB exposure.Dams were treated during pregnancy from GD15 to GD19 and during breast-feeding. A constant reduction of the growth rate in both male and female offspring from weaning to adulthood was observed in exposed animals. Long-lasting alterations on hypothalamic-pituitary GH axis were indeed observed in PCB-exposed rats in adulthood: increased somatostatin expression in hypothalamic periventricular nucleus (both males and females) and lateral arcuate nucleus (males, only) and decreased GH mRNA levels in the pituitary of male rats. Plasma IGF-1 levels were higher in PCB-exposed male and female animals as compared with controls at weaning and tended to be higher at PN60. Plasma testosterone and thyroid hormone concentrations were not significantly affected by exposure to PCBs. In adulthood, PCBs caused a significant reduction of bone mineral content and cortical bone thickness of tibiae in male rat joint to increased width of the epiphyseal cartilage disk. In conclusion, the developmental exposure to the four selected PCB compounds used in the present study induced far-reaching effects in the adult offspring, the male rats appearing more sensitive than females. 相似文献
983.
Giovanni Vitale Valentina Ruggieri Monica Filaferro Claudio Frigeri Silvia Alboni Fabio Tascedda Nicoletta Brunello Remo Guerrini Carlo Cifani Maurizio Massi 《Psychopharmacology》2009,207(2):173-189
Introduction
The present study was designed to assess the antidepressant effects of UFP-101, a selective nociceptin/orphanin FQ peptide (NOP) receptor antagonist, in a validated animal model of depression: the chronic mild stress (CMS).Materials and methods and Results
UFP-101 (5, 10 and 20 nmol/rat; i.c.v., once a day for 21 days) dose- and time-dependently reinstated sucrose consumption in stressed animals without affecting the same parameter in non-stressed ones. In the forced swimming test, UFP-101 reduced immobility of stressed rats from day 8 of treatment. After a 3-week treatment, rats were killed for biochemical evaluations. UFP-101 abolished increase in serum corticosterone induced by CMS and reverted changes in central 5-HT/5-HIAA ratio. The behavioural and biochemical effects of UFP-101 mimicked those of imipramine, the reference antidepressant drug, administered at the dose of 15 mg/kg (i.p.). Co-administration of nociceptin/orphanin FQ (5 nmol/rat, from day 12 to 21) prevented the effects of UFP-101. Brain-derived neurotrophic factor mRNA and protein in hippocampus were not reduced by CMS nor did UFP-101 modify these parameters.Discussion and Conclusion
This study demonstrated that chronic treatment with UFP-101 produces antidepressant-like effects in rats subjected to CMS supporting the proposal that NOP receptors represent a candidate target for the development of innovative antidepressant drugs. 相似文献984.
985.
Muratori P Czaja AJ Muratori L Granito A Guidi M Ferri S Volta U Mantovani W Pappas G Cassani F Lenzi M Bianchi FB 《Digestive diseases and sciences》2007,52(1):179-184
Antibodies to liver/kidney microsome type 1 occur in Italian patients with hepatitis C, but rarely develop in North American
patients. Our goals were to compare the frequencies of the HLA markers associated with autoimmune expression in Italian and
North American patients with chronic hepatitis C and to determine genetic bases for regional differences in antibody production.
HLA B8, DR3, DR4, DR7, DR11, DR13, DQ2, and the B8-DR3-DQ2 haplotype were determined by microlymphocytotoxicity and polymerase
chain reaction in 105 Italian patients (50 with microsomal antibodies), 100 North American patients (none with microsomal
antibodies), and Italian and North American healthy control subjects. Italian patients with microsomal antibodies differed
from North American patients without these antibodies by having a higher frequency of HLA DR7 (54% vs. 27%, P=0.002). HLA DR7 occurred more frequently in seropositive Italian patients than in seronegative counterparts (54% vs. 11%
P < 0.0001), Italian healthy control subjects (54% vs. 29%, P=0.0009), and North American healthy control subjects (54% vs. 19%, P < 0.0001). The frequency of HLA DR7 was similar in North American patients and controls (27% vs. 19%, P=0.2), but it was lower than in Italian controls (19% vs. 29%, P=0.059). Seropositive Italian patients had a lower frequency of HLA DR11 than seronegative Italian patients and Italian controls
(18% vs. 34%, P=0.07, and 18% vs. 35%, P=0.02, respectively). In contrast to seropositive Italian patients, North American patients had HLA DR4 (30% vs. 12%, P=0.02), HLA DR13 (29% vs. 10%, P=0.01), and the B8-DR3-DQ2 haplotype (23% vs. 6%, P=0.01) more often. Similarly, HLA DR4 and the B8-DR3-DQ2 phenotype were more frequent in North American patients than in Italian
controls (30% vs. 16%, P=0.005, and 23% vs. 7%, P=0.00002, respectively). HLA DR7 is associated with the development of microsomal antibodies in Italian patients with chronic
hepatitis C. The lower frequency of HLA DR7 in North America could contribute to the rarity of these antibodies in this region.
HLA DR11 may be protective against the development of microsomal antibodies in Italian patients, whereas HLA DR4, HLA DR13,
and the B8-DR3-DQ2 haplotype may be protective in North American patients. 相似文献
986.
987.
Bosetti C Levi F Lucchini F Zatonski WA Negri E La Vecchia C 《Journal of hepatology》2007,46(5):827-839
BACKGROUND/AIMS: Cirrhosis mortality has registered large changes over the last few decades. METHODS: Age-standardized (world standard) cirrhosis mortality rates per 100,000 were computed for 41 countries worldwide over the period 1980-2002 using data from the WHO mortality database. RESULTS: In the early 1980s, the highest rates were in Mexico, Chile (around 55/100,000 men and over 14/100,000 women), France, Italy, Portugal, Austria, Hungary and Romania (around 30-35/100,000 men and 10-15/100,000 women). Mortality from cirrhosis has been steadily declining in most countries worldwide since the mid or late 1970s (annual percent change, APC, between -5% and -1.5% in the last decade only for both sexes). In southern Europe, rates in the early 2000s were less than halved compared to earlier decades. In contrast, rates have been rising in Eastern European countries to reach extremely high values in the mid 1990s, and declined only thereafter. In the UK rates were still steadily rising (APC around +7% in men and +3% in women from England and Wales, and +9% in men and +7% in women from Scotland). CONCLUSIONS: Mortality from cirrhosis shows favourable trends in most countries of the world, following the reduction in alcohol consumption and hepatitis B and C virus infection. The steady upward trends observed over more recent calendar periods in the UK and central and eastern European countries are attributed to the persistent increase in the prevalence of alcohol consumption. 相似文献
988.
Brazzoli M Crotta S Bianchi A Bagnoli F Monaghan P Wileman T Abrignani S Merola M 《Journal of hepatology》2007,46(1):53-59
BACKGROUND/AIMS: The establishment of HCV replicon systems strongly improved the research on the replication processes but poorly advanced our knowledge on the subcellular localization of the structural glycoproteins, mainly due to their low expression. We sought to verify whether reinforcing E1E2 expression in the context of both HCV genomic and subgenomic replicon from either homologous or heterologous strains leads to formation of supramolecular structures including structural and nonstructural proteins. METHODS: Robust expression of HCV glycoproteins was achieved by stable expression of E1E2p7 from genotype 1a and 1b. RESULTS: In these cells, E1 and E2 triggered the formation of dot-like structures in which they co-localized with core and the nonstructural proteins NS3 and NS5A. Confocal microscopy analyses suggested that accumulation of HCV proteins occurs in an ER-derived subcompartment. Moreover, by labeling de novo-synthesized HCV RNA, we showed that these structures constitute a site of viral RNA synthesis. CONCLUSIONS: Expression in trans of HCV glycoproteins in the context of replicative viral genome or subgenome generates accumulation of structural and nonstructural viral proteins in peculiar cytoplasmic structures. The simultaneous presence of viral RNA, structural and nonstructural protein suggests that these complexes represent not only sites of HCV replication but also potential places of viral pre-budding. 相似文献
989.
Protection against inflammation- and autoantibody-caused fetal loss by the chemokine decoy receptor D6 下载免费PDF全文
Martinez de la Torre Y Buracchi C Borroni EM Dupor J Bonecchi R Nebuloni M Pasqualini F Doni A Lauri E Agostinis C Bulla R Cook DN Haribabu B Meroni P Rukavina D Vago L Tedesco F Vecchi A Lira SA Locati M Mantovani A 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(7):2319-2324
Fetal loss in animals and humans is frequently associated with inflammatory conditions. D6 is a promiscuous chemokine receptor with decoy function, expressed in lymphatic endothelium, that recognizes and targets to degradation most inflammatory CC chemokines. Here, we report that D6 is expressed in placenta on invading extravillous trophoblasts and on the apical side of syncytiotrophoblast cells, at the very interface between maternal blood and fetus. Exposure of D6-/- pregnant mice to LPS or antiphospholipid autoantibodies results in higher levels of inflammatory CC chemokines and increased leukocyte infiltrate in placenta, causing an increased rate of fetal loss, which is prevented by blocking inflammatory chemokines. Thus, the promiscuous decoy receptor for inflammatory CC chemokines D6 plays a nonredundant role in the protection against fetal loss caused by systemic inflammation and antiphospholipid antibodies. 相似文献
990.
Triggering sleep slow waves by transcranial magnetic stimulation 总被引:5,自引:1,他引:4
Massimini M Ferrarelli F Esser SK Riedner BA Huber R Murphy M Peterson MJ Tononi G 《Proceedings of the National Academy of Sciences of the United States of America》2007,104(20):8496-8501
During much of sleep, cortical neurons undergo near-synchronous slow oscillation cycles in membrane potential, which give rise to the largest spontaneous waves observed in the normal electroencephalogram (EEG). Slow oscillations underlie characteristic features of the sleep EEG, such as slow waves and spindles. Here we show that, in sleeping subjects, slow waves and spindles can be triggered noninvasively and reliably by transcranial magnetic stimulation (TMS). With appropriate stimulation parameters, each TMS pulse at <1 Hz evokes an individual, high-amplitude slow wave that originates under the coil and spreads over the cortex. TMS triggering of slow waves reveals intrinsic bistability in thalamocortical networks during non-rapid eye movement sleep. Moreover, evoked slow waves lead to a deepening of sleep and to an increase in EEG slow-wave activity (0.5-4.5 Hz), which is thought to play a role in brain restoration and memory consolidation. 相似文献