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101.
Li Pira G Bottone L Ivaldi F Pelizzoli R Del Galdo F Lozzi L Bracci L Loregian A Palù G De Palma R Einsele H Manca F 《International immunology》2004,16(5):635-642
CD8 and CD4 lymphocytes control cytomegalovirus (CMV) infection in immunocompetent individuals, while patients with defective cellular immunity are prone to endogenous reactivation of latent CMV or, like seronegative subjects, prone to primary infection. Administration of CMV-specific CD8 lymphocytes was beneficial for immunocompromised hemopoietic stem cell (HSC) graft recipients. Since CD4 cells contribute to expansion of cytotoxic T lymphocytes (CTL), we defined new T(h) peptides on the immunodominant protein pp65 recognized by CD4 cells from HLA-typed subjects, in the perspective of complementing CTL administration with CMV-specific T(h) cells. Screening by ELISPOT on CD4 and CD8 subsets using overlapping peptides identified 10 novel CD4 peptides. To simplify procedures to generate T cell lines, we used a CD4 peptide library for T cell stimulation instead of ill-defined viral lysates, without the requirement of dendritic cells. This library stimulated CMV-specific CD4 cells. In fact, peptide-induced CD4 cells responded to pp65 and to the viral lysate. These cells were also devoid of alloreactivity after one stimulation cycle. Since Good Manufacturing Procedure-grade peptides can be synthesized, culture conditions are simplified and alloreactivity is rapidly lost, these procedures based on peptide stimulation can facilitate implementation of adoptive reconstitution of CD4 responses in immunocompromised patients also in the case when the HSC allodonor is available for generation of the T cell line. 相似文献
102.
Rationale (+)-HA-966, a partial agonist at the glycine/NMDA modulatory site, significantly reduced IV cocaine self-administration in a fixed-ratio (FR) schedule. Since this effect was observed studying only one dose of cocaine and considering the characteristic bell-shaped curve generated by cocaine in self-administration studies under FR schedules, the precise nature of the effect is not clear.Objective To identify the nature of the effect of (+)-HA-966 on cocaine self-administration under fixed ratio (FR) and progressive ratio (PR) schedules of reinforcement.Methods Rats were prepared with IV catheters and trained to self-administer cocaine. In the first experiment three doses of (+)-HA-966 (10, 30 and 100 µg/5 µl ICV) were evaluated for their effects on 0.25 mg/0.1 ml per infusion cocaine self-administration on FR1 with 20-s time-out (TO). Next, 30 µg/5 µl ICV (+)-HA-966 was evaluated as pretreatment on a complete dose-response for cocaine self-administration. In a third experiment the effect of the same dose was evaluated on cocaine or food self-administered on the PR schedule.Results (+)-HA-966 at doses of 10 or 30 µg reduced cocaine self-administration in an FR1 schedule during the first hour interval of the 2-h session. This partial agonist at the glycine/NMDA modulatory site also reduced the number of injections of cocaine earned during the first hour of the session but not the final ratio reached under a PR schedule. However, under this schedule (+)-HA-966 also reduced operant responding for food reinforcement.Conclusions (+)-HA-966 reduced responding maintained by cocaine or food. Whether (+)-HA-966 induces a general motivational rather than a performance deficit, leading to reduced responding for either cocaine and food, is unclear. 相似文献
103.
Inhibition of smoothened signaling prevents ultraviolet B-induced basal cell carcinomas through regulation of Fas expression and apoptosis 总被引:11,自引:0,他引:11
Athar M Li C Tang X Chi S Zhang X Kim AL Tyring SK Kopelovich L Hebert J Epstein EH Bickers DR Xie J 《Cancer research》2004,64(20):7545-7552
Abnormal activation of the hedgehog-signaling pathway is the pivotal abnormality driving the growth of basal cell carcinomas (BCCs), the most common type of human cancer. Antagonists of this pathway such as cyclopamine may therefore be useful for treatment of basal cell carcinomas and other hedgehog-driven tumors. We report here that chronic oral administration of cyclopamine dramatically reduces ( approximately 66%) UVB induced basal cell carcinoma formation in Ptch1(+/-) mice. Fas expression is low in human and murine basal cell carcinomas but is up-regulated in the presence of the smoothened (SMO) antagonist, cyclopamine, both in vitro in the mouse basal cell carcinoma cell line ASZ001 and in vivo after acute treatment of mice with basal cell carcinomas. This parallels an elevated rate of apoptosis. Conversely, expression of activated SMO in C3H10T1/2 cells inhibits Fas expression. Fas/Fas ligand interactions are necessary for cyclopamine-mediated apoptosis in these cells, a process involving caspase-8 activation. Our data provide strong evidence that cyclopamine and perhaps other SMO antagonists are potent in vivo inhibitors of UVB-induced basal cell carcinomas in Ptch1(+/-) mice and likely in humans because the majority of human basal cell carcinomas manifest mutations in PTCH1 and that a major mechanism of their inhibitory effect is through up-regulation of Fas, which augments apoptosis. 相似文献
104.
A case of suspected lung metastases from colorectal adenocarcinoma is discussed. A diagnostic approach for follow-up of resected patients is proposed. It includes available diagnostic imaging for the characterization of metastatic pulmonary nodules together with methods for the differential diagnosis between primary malignant nodules and benign nodules. 相似文献
105.
Del Signore A Gotti C Rizzo A Moretti M Paggi P 《Journal of neuropathology and experimental neurology》2004,63(2):138-150
Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic transmission in autonomic ganglia, which innervate and control the activity of most visceral organs. By combining ultrastructural, immunocytochemical, and pharmacological analyses, we characterized the nAChR subtypes in the rat superior cervical ganglion (SCG) and the effect of pre- and postganglionic nerve crush on their number in the ganglion and their distribution at the intraganglionic synapses. Binding with radioactive nicotinic ligands, immunoprecipitation, and immunolocalization experiments revealed the presence of different nAChR subtypes: those containing the alpha3 subunit associated with beta4 and/or beta2 subunits that bind 3H-Epibatidine with high affinity, and those containing the alpha7 subunit that bind 125I-alphaBungarotoxin. After postganglionic nerve crush, the number of nicotinic receptors and immunopositive intraganglionic synapses for each nAChR subunit strongly decreased. Both the number of nAChRs and immunoreactivity recovered 26 days after injury, when regenerating postganglionic fibers had reinnervated the peripheral target organs, as shown by the restoration of tyrosine hydroxylase immunoreactivity in the iris. This observation and the lack of any effect of preganglionic nerve crush on the number of nicotinic receptors suggest that the peripheral targets affect the organization of intraganglionic synapses in adult SCG. 相似文献
106.
Tognini G Arisi A Ferrozzi F De Blasi M De Filippo M Paoli G Patti A Bnà C Zompatori M Ardissimo D Gherli T 《La Radiologia medica》2004,108(5-6):470-486
Coronary angiography is nowadays the diagnostic standard in the evaluation of coronary artery anatomy, in the identification of stenoses and in the follow-up of revascularization procedures (PTCA-stenting, bypass). The limitations of such technique in terms of invasivity and high cost has targeted research efforts towards the development of non invasive diagnostic tools. Technological evolution in the field of helical CT has provided 2, 4, 8 and 16 detector-row multislice scanners characterized by progressive improvements in terms of spatial and temporal resolution that have made them increasingly suitable for the analysis of moving structures with high quality anatomic detail. The main cardiologic applications of multislice CT include coronary calcium scoring, the evaluation of coronary vascular anatomy and disease, follow-up of revascularization procedures (stenting, bypass), and the evaluation of cardiac walls and chambers. The aim of this paper is to describe the applications of sixteen detector-row multisclice CT in non invasive evaluation of cardiac and coronary diseases. 相似文献
107.
Careful HRCT evaluation of the preferential distribution of micronodular lesions within the secondary lobule provides a fundamental contribution in the correct interpretation of the different associated patterns. This paper suggests a modern diagnostic algorithm that, together with clinical-anamnestic data and additional imaging features, is able to provide a definitive diagnosis or to reduce the possible differential diagnoses. 相似文献
108.
Secchiero P Gonelli A Carnevale E Corallini F Rizzardi C Zacchigna S Melato M Zauli G 《Neoplasia (New York, N.Y.)》2004,6(4):364-373
Starting from the observation that tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)/Apo-2L protein is expressed in both malignant and inflammatory cells in some highly vascularized soft tissue sarcomas, the angiogenic potential of TRAIL was investigated in a series of in vitro assays. Recombinant soluble TRAIL induced endothelial cell migration and vessel tube formation to a degree comparable to vascular endothelial growth factor (VEGF), one of the best-characterized angiogenic factors. However, the proangiogenic activity of TRAIL was not mediated by endogenous expression of VEGF. Although TRAIL potentiated VEGF-induced extracellular signal-regulated kinase (ERK) phosphorylation and endothelial cell proliferation, the combination of TRAIL + VEGF did not show additive effects with respect to VEGF alone in inducing vessel tube formation. Thus, although TRAIL has gained attention as a potential anticancer therapeutic for its ability to induce apoptosis in a variety of cancer cells, our present data suggest that TRAIL might also play an unexpected role in promoting angiogenesis, which might have therapeutic implications. 相似文献
109.
Spontaneous multiple pregnancy after uterine artery embolization for uterine fibroid: case report 总被引:2,自引:0,他引:2
D'Angelo A Amso NN Wood A 《European journal of obstetrics, gynecology, and reproductive biology》2003,110(2):245-246
Uterine artery embolization (UAE) is an effective non-surgical treatment for uterine myomas. Effects on fertility preservation are still under investigation. Various complications have been reported as well as few pregnancies. We report a case of spontaneous twins pregnancy following UAE in a woman who desired to preserve fertility. 相似文献
110.
Lafortuna CL Jahoda M Azzellino A Saibene F Colombini A 《European journal of applied physiology》2003,90(3-4):387-395
Twenty-four Mediterranean fin whales were tracked in open sea with a method based on the assessment of the animal differential position in respect of the observer's absolute position aboard a vessel, with the concomitant recording of the respiratory activity. Short distance video recording was also performed in two whales, permitting the simultaneous determination of single breath expiratory (TE) and inspiratory (TI) durations. In the 24 whales swimming at an average velocity of 1.39 (0.47) m·s–1 [mean (SD), range: 0.62–2.44 m·s–1], 2068 breaths organized in 477 respiratory cycles were observed. Each cycle entailed a prolonged apnoea dive phase [225 (91) s, Tdive) followed by a period near the surface [62 (28) s, surfacing], during which a series of breaths [4.6 (1.8)] was performed at short intervals. On the basis of track length and swimming velocity, two groups of animals were devised differing for convolution of the course (p<0.001), extension of ranging territory (p<0.01) and horizontal swimming velocity (p<0.05), which may represent two distinct behaviours. A possibly general mechanism of control of breathing in cetaceans was found, consistent with a model of constant tidal volume and variable respiratory frequency. Coherently with this model,
TE was independent of TI or Tdive, in line with a passive expiration, while
TI appeared to be negatively correlated with
Tdive (p<0.05), otherwise suggesting, similarly with terrestrial mammals, a significant role of hypercapnic stimulation. The estimated O2
consumption of about 150 l·min–1 is in line with the general allometric regression for mammals and corresponds to an energetic expenditure of 85–95 kJ·kg–1·day–1.Partially presented as a poster at The World Marine Mammal Science Conference and 12th Annual Conference of the European Cetacean Society, Monaco (Montecarlo), 20–24 January 1998.Angelo Colombini provided technical assistance. 相似文献