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121.
Measles notifications in Italy underestimate the actual incidence by a factor of ten, as it is ascertained by seroepidemiological investigation. In the decade 1980-89, 45,000 measles cases were notified, on average, per year. Since 1988 mass vaccination campaigns were implemented in several Italian regions. The strategy aimed to offer the prophylaxis actively to all children aged 13 months to 8-12 year for whom a sure recollection of measles was absent. The study has aimed to evaluate the impact of the strategy that worked in the period 1989-91, on the standardised average annual incidence of measles notification, comparing the periods 1985-89 and 1990-94. A reduction of 45% resulted all over Italy. On the contrary the incidence of chickenpox notifications has increased, indicating that the notification system did not worse.  相似文献   
122.
The enzyme carnitine-acylcarnitine translocase (CACT) is involved in the transport of long-chain fatty acids into mitochondria. CACT deficiency is a life-threatening, recessively inherited disorder of lipid beta-oxidation which manifests in early infancy with hypoketotic hypoglycemia, cardiomyopathy, liver failure, and muscle weakness. We report here the clinical, biochemical, and molecular features of six CACT-deficient patients from Italy, Spain, and North America who exhibited significant clinical heterogeneity. In five patients (Patients 1, 2, 4, 5, and 6) the disease manifested in the neonatal period, while the remaining patient (Patient 3), the younger sibling of an infant who had died with clinical suspicion of fatty acid oxidation defect, has been treated since birth and was clinically asymptomatic at 4.5 years of age. Patients 1 and 4 were deceased within 6 months from the onset of this study, while the remaining four are still alive at 8, 4.5, 3.5, and 2 years, respectively. Sequence analysis of the CACT gene (SLC25A20) disclosed five novel mutations and three previously reported mutations. Three patients were homozygous for the identified mutations. Two of the novel mutations (c.718+1G>C and c.843+4_843+50del) altered the donor splice site of introns 7 and 8, respectively. The 47-nt deletion in intron 8 caused both skipping of exon 8 only and skipping of exons 6-8. Four mutations [[c.159dupT;c.163delA] ([p.Gly54Trp;p.Thr55Ala]) c.397C>T (p.Arg133Trp), c.691G>C (p.Asp231His), and c.842C>T (p.Ala281Val)] resulted in amino acid substitutions affecting evolutionarily conserved regions of the protein. Interestingly, one of these exonic mutations (p.Ala281Val) was associated with a splicing defect also characterized by skipping of exons 6-8. The deleterious effect of the p.Arg133Trp substitution was demonstrated by measuring CACT activity upon expression of the normal and the mutant protein in E. coli and functional reconstitution into liposomes. Combined analysis of clinical, biochemical, and molecular data failed to indicate a correlation between the phenotype and the genotype.  相似文献   
123.

Background  

To clarify the immunological alterations leading to classical Kaposi sarcoma (cKS) among people infected with KS-associated herpesvirus (KSHV).  相似文献   
124.
The 6-minute walk test (6MWT) is a simple field test that is widely used in clinical settings to assess functional exercise capacity. However, studies with healthy subjects are scarce. We hypothesized that the 6MWT might be useful to assess exercise capacity in healthy subjects. The purpose of this study was to evaluate 6MWT intensity in middle-aged and older adults, as well as to develop a simple equation to predict oxygen uptake (V˙O2) from the 6-min walk distance (6MWD). Eighty-six participants, 40 men and 46 women, 40-74 years of age and with a mean body mass index of 28±6 kg/m2, performed the 6MWT according to American Thoracic Society guidelines. Physiological responses were evaluated during the 6MWT using a K4b2 Cosmed telemetry gas analyzer. On a different occasion, the subjects performed ramp protocol cardiopulmonary exercise testing (CPET) on a treadmill. Peak V˙O2 in the 6MWT corresponded to 78±13% of the peak V˙O2 during CPET, and the maximum heart rate corresponded to 80±23% of that obtained in CPET. Peak V˙O2 in CPET was adequately predicted by the 6MWD by a linear regression equation: V˙O2 mL·min-1·kg-1 = -2.863 + (0.0563×6MWDm) (R2=0.76). The 6MWT represents a moderate-to-high intensity activity in middle-aged and older adults and proved to be useful for predicting cardiorespiratory fitness in the present study. Our results suggest that the 6MWT may also be useful in asymptomatic individuals, and its use in walk-based conditioning programs should be encouraged.  相似文献   
125.
BACKGROUND AND OBJECTIVE: In recent years, conventional dose of fludarabine (FLU) alone or in combination with other drugs has been reported to be effective in the treatment of low-grade non-Hodgkin's lymphomas (LG-NHL). In particular, FLU and cyclophosphamide (CY) or FLU and mitoxantrone or idarubicin combined regimens have shown considerable therapeutic activity both as first line and salvage therapies, producing overall response rates ranging from 40-50% in previously treated patients and up to 70-90% in untreated ones. However severe neutropenia and infective complications have been reported in a significant number of patients. Based on these premises we evaluated the efficacy and toxicity of a new regimen combining low-doses of FLU with epirubicin (EPI) and CY (FLEC) in a group of advanced treatment-requiring LG-NHL patients. The aim of this study was to evaluate a strategy aimed at lowering therapy-related toxic effects without affecting the reported good response rate. DESIGN AND METHODS: Thirty patients with de novo, relapsed or refractory LG-NHL entered the study. FLEC regimen was as follows: EPI 60 mg/m(2) i.v. on day one, plus FLU 15 mg/m(2)/day i.v. (max 25 mg) and CY 250 mg/m(2)/day i.v. for four days. RESULTS: All 30 patients were evaluable for response, 13 (43%) fulfilled the criteria for CR and 11 (36%) for PR with an overall response rate of 79%. None of the 13 patients who achieved CR had relapsed after a follow-up of 2 to 23 months (median duration 13 months). With regard to age, 13/14 older patients (>/= 70 years) responded to the treatment and 9 of them maintained their response after a median of 13 months (range 2-22); six of the 14 (43%) obtained a CR. Therapy-related toxicity was mild regardless of age, neutropenia (43%) and fever of undetermined origin (26%) being the major side effects. Remarkably, a documented infection was recorded only in 2/30 (6%) patients. INTERPRETATION AND CONCLUSIONS: A low-dose FLU-based FLEC regimen appeared to be effective for advanced treatment-requiring LG-NHL, reproducing a similar overall response rate (79%) reported to have been achieved with other FLU based combination therapies. Toxic side effects were negligible and in particular documented infections were remarkably uncommon even in the group of elderly patients.  相似文献   
126.
Twenty-five elderly patients with untreated indolent non-Hodgkin lymphoma were treated with oral fludarabine 25 mg/m(2)/d (40 mg total dose) and cyclophosphamide 150 mg/m(2)/d, both for four consecutive days, repeated every 28 d for four cycles. In all, 21 (84%) patients were responsive: 10 patients achieved complete remission while partial response was obtained in 11. During an observation period of 37 months, there was an overall survival rate of 70% and a median event-free survival of 20 months. Haematological and extra-haematological toxicity were mild. This reduced-dose Flu-based oral regimen showed good efficacy and was simple to administer on an outpatient basis.  相似文献   
127.
Melatonin is the main secretory product of the pineal gland, and it is involved in the regulation of periodic events. A melatonin production independent of the photoperiod is typical of the gut. However, the local physiological role of melatonin at the intestinal tract is poorly characterized. In this study, we evaluated the anti‐inflammatory activities of melatonin in an in vitro model of inflamed intestinal epithelium. To this purpose, we assessed different parameters usually associated with intestinal inflammation using IL‐1β‐stimulated Caco‐2 cells. Differentiated monolayers of Caco‐2 cells were preincubated with melatonin (1 nmol/L‐50 μmol/L) and then exposed to IL‐1β. After each treatment, different inflammatory mediators, DNA‐breakage, and global DNA methylation status were assayed. To evaluate the involvement of melatonin membrane receptors, we also exposed differentiated monolayers to melatonin in the presence of luzindole, a MT1 and MT2 antagonist. Our results showed that melatonin, at concentrations similar to those obtained in the lumen gut after ingestion of dietary supplements for the treatment of sleep disorders, was able to attenuate the inflammatory response induced by IL‐1β. Anti‐inflammatory effects were expressed as both a decrease of the levels of inflammatory mediators, including IL‐6, IL‐8, COX‐2, and NO, and a reduced increase in paracellular permeability. Moreover, the protection was associated with a reduced NF‐κB activation and a prevention of DNA demethylation. Conversely, luzindole did not reverse the melatonin inhibition of stimulated‐IL‐6 release. In conclusion, our findings suggest that melatonin, through a local action, can modulate inflammatory processes at the intestinal level, offering new opportunities for a multimodal management of IBD.  相似文献   
128.
A fraction of chronic lymphocytic leukaemia (CLL) cases carry highly homologous B-cell receptors (BCR), i.e. characterized by non-random combinations of immunoglobulin heavy-chain variable ( IGHV ) genes and heavy-chain complementarity determining region-3 (HCDR3), often associated with a restricted selection of IGVK/L light chains. Such 'stereotyped' BCR occur more frequently in CLL with unmutated (UM) than mutated (M) IGHV genes. We analysed 1426 IG rearrangements (from 1398 CLL cases) by a clustering driven by HCDR3 similarities. Molecular findings were correlated to time-to-treatment (TTT) and presence of known prognosticators. Sixty-nine clusters (319 IG-rearrangements, 22·4%) with stereotyped BCR were identified. Among 30 confirmed clusters (≥3 IG-rearrangements/cluster), we found 14 novel clusters, of which 11 had M IG rearrangements (M clusters) and predominantly (8/11) used IGHV3 subgroup genes. Recurrent cluster-biased amino acid changes were found throughout IGHV sequences of these 'M clusters'. Regarding clinical outcome: (i) UM CLL from the IGHV1-2/1-3/1-18/1-46/7-4-1/IGKV1-39 cluster had poorer prognosis than UM/M cases, or UM cases using the same IGHV genes but not in clusters; (ii) M CLL from the IGHV3-21/IGLV3-21 cluster had TTT similar to UM CLL, and shorter than M CLL expressing IGHV3-21 but not in cluster. Altogether, our analysis identified additional molecular and clinical features for CLL expressing stereotyped BCR.  相似文献   
129.
Summary Antigenic expression of CD54 and CD58 adhesion molecules was investigated on leukemic blast samples from ten patients with acute lymphoblastic (ALL) and 14 with acute myeloblastic (AML) leukemia. The mean intensity of fluorescence (MIF) was calculated and correlated with sensitivity of blast cells to the lytic activity of allogeneic lymphokine-activated killer (LAK) cells. CD54 antigen was expressed in all AML cases with an MIF of 11.2 while in ALL, though present in the majority of cases, it was absent in one case and expressed in less than 30% of blasts in two others, with an overall MIF of 3.0. CD58 expression was similar in both groups of patients, with an MIF of 7.6 in ALL and 7.0 in AML. In addition, in six of the ten ALL cases and in two of the 14 AML cases, leukemic blasts proved to be resistant to the cytotoxic activity of normal allogeneic LAK effectors. In these LAK-resistant patients, the CD54 antigenic expression was lower (p=0.03) than in LAK-sensitive patients with an MIF of 1.7 vs 4.9 in ALL and 1.35 vs 12.9 in AML cases. Finally, blocking of CD54 and/or CD58 receptors on leukemic blasts resulted in a slight reduction of51Cr release. Findings suggest that CD54 is differently expressed on myeloid and lymphoid blasts and that there is a correlation between CD54 MIF and susceptibility of blasts to the LAK activity.  相似文献   
130.
The possibility that serum from hairy-cell leukaemia (HCL) patients at diagnosis may show an inhibitory effect on the in vitro colony growth of normal haemopoietic progenitor cells has been suggested. Several studies have documented the efficacy of alpha-Interferon (alpha-IFN) in inducing a complete restoration of peripheral blood values and, in some cases, a complete clinical remission. In this study we have evaluated the regulatory effect of serum, collected before and after 3 and 12 months of alpha-IFN treatment, from 10 patients with untreated HCL, on the in vitro growth of normal bone marrow CFU-GM, BFU-E and CFU-MK. The effect of conditioned media, prepared from enriched hairy cells (HC) cultured in synthetic medium, on the growth of normal haemopoietic progenitors was also investigated. The results obtained confirm that sera from untreated HCL patients display a variable degree of inhibitory activity in the progenitor cell compartments analysed. Disappearance of the inhibitory activity, particularly evident for the erythroid compartment, was found only in patients who displayed a disappearance of circulating HC and a good haematological response after prolonged (12 months) treatment with alpha-IFN. The possibility that the serum of patients with HCL may contain a haemopoietic inhibitory factor, released by the neoplastic HC population, is suggested.  相似文献   
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