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This consensus paper on behalf of the Study Group on Sports Cardiology of the European Society of Cardiology follows a previous one on guidelines for sports participation in competitive and recreational athletes with supraventricular arrhythmias and pacemakers. The question of imminent life-threatening arrhythmias is especially relevant when some form of ventricular rhythm disorder is documented, or when the patient is diagnosed to have inherited a pro-arrhythmogenic disorder. Frequent ventricular premature beats or nonsustained ventricular tachycardia may be a hallmark of underlying pathology and increased risk. Their finding should prompt a thorough cardiac evaluation, including both imaging modalities and electrophysiological techniques. This should allow distinguishing idiopathic rhythm disorders from underlying disease that carries a more ominous prognosis. Recommendations on sports participation in inherited arrhythmogenic conditions and asymptomatic gene carriers are also discussed: congenital and acquired long QT syndrome, short QT syndrome, Brugada syndrome, catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular cardiomyopathy and other familial electrical disease of unknown origin. If an implantable cardioverter defibrillator is indicated, it is no substitute for the guidelines relating to the underlying pathology. Moreover, some particular recommendations for patients/athletes with an implantable cardioverter defibrillator are to be observed.  相似文献   
3.
The reporting quality of publications of clinical trials can affect the quality of clinical decision-making. We systematically assessed the quality of publications of large multicenter trials evaluating immunosuppressive regimens in de novo kidney transplantation. Study quality, reporting quality and accessibility of the results of 63 publications were assessed independently by three blinded investigators using an instrument combining the Jadad scale with a list of reporting quality items. Study quality was rated with an average of only 2.3 (range 1-5) on the Jadad scale. Unblinded studies were reported in 68.3% of publications and follow-up longer than 12 months was reported for only 13 out of 50 studies. The reviewed publications fulfilled an average of 69.1% of the reporting quality criteria. Fifty-four percent of publications did not report both treated and biopsy-proven rejections. Whether reported graft survival was censored for death could not be determined for 27% of publications. Only a few publications gave confidence intervals (CIs) or stated whether additional analyses were pre-specified. Even the largest trials of immunosuppression in kidney transplantation show considerable quality deficits in their design and publication. Additional efforts are required of investigators, editors and sponsors to achieve maximum study and reporting quality.  相似文献   
4.
Summary The effect of the combined administration of verapamil (i.p. twice daily) and doxorubicin (i.v once weekly) was tested in mice bearing the following: (a) a tumor with induced resistance to doxorubicin (B16VDXR melanoma line); (b) a tumor inherently resistant (MXT mammary carcinoma); and (c) four solid tumors sensitive to doxorubicin (B16 melanoma, B16V melanoma line, M5076 reticulum cell sarcoma, and Lewis lung carcinoma). Verapamil, given according to this treatment schedule, reached peak plasma concentrations of 3 M. Such treatment did not enhance doxorubicin activity on either inherently or induced resistant tumors, whereas it significantly enhanced doxorubicin growth inhibition in all the sensitive tumors except the Lewis lung carcinoma. Doxorubicin pharmacokinetics after administration of the drug alone and in combination with verapamil was analyzed after the first and repeated treatments in animals bearing B16 melanoma or its resistant subline B16VDXR. The resistance of the B16VDXR line was associated with the ability of the tumor to retain less doxorubicin (AUC=83 g h/g) than the sensitive tumor B16 (AUC=204 g h/g) in spite of similar initial levels. The potentiating effect of doxorubicin activity by, verapamil in B16 melanoma was not associated with increased doxorubicin levels or retention in the tumor, nor were differences in doxorubicin levels or retention found in the B16VDXR line. The combined treatment did not modify doxorubicin pharmacokinetics in plasma, heart, or spleen. These studies suggest that verapamil in vivo is ineffective in potentiating doxorubicin activity in tumors against which doxorubicin is inactive, that sensitive tumors are heterogeneous in their sensitivity to modulation by verapamil, and that this effect is not associated with modification of doxorubicin pharmacokinetics.This work was supported by grant no. 84.00855.44 of the Finalized Project Oncologia from the Consiglio Nazionale delle Ricerche, Rome  相似文献   
5.
Hepatitis C virus (HCV) and aberrant somatic hypermutation (SHM) have each been suggested to contribute to the development of B-cell non-Hodgkin's lymphoma (NHL). The incidence of PIM-1, PAX-5, RhoH/TTF, and c-MYC mutations in tumour biopsy specimens from 32 HCV-infected B-cell NHL patients was analysed to determine whether the extent of aberrant SHM among these patients differed from that previously reported for HCV-negative B-cell NHL patients. Mutation of PIM-1, PAX-5, RhoH/TTF, and c-MYC was detected in 4 (13%), 5 (16%), 4 (13%), and 4 (13%) of 32 samples, respectively. In HCV-positive B-cell NHL patients, the frequency of aberrant SHM was lower than that already found in HCV-negative B-cell NHL patients. This indicates that, unlike B-cell lymphomas from HCV-negative patients, aberrant SHM may not contribute significantly to malignant transformation in HCV-associated B-cell lymphomas.  相似文献   
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Diabetic neuropathy affects both sensory and autonomic peripheral nerve fibres. Vasoactive intestinal polypeptide (VIP) is present in autonomic fibres which modulate sweat secretion, while calcitonin gene-related peptide (CGRP) is localized to cutaneous sensory fibres. In this study, immunohistochemistry and image analysis were used to assess changes of VIP and CGRP, and of the pan-neuronal marker protein gene-product (PGP)-9.5, in skin biopsies of 18 patients affected by type 1 diabetes (age range 18–46 years) and from seven aged-matched controls. Patients were divided into three groups: group 1 (n=6), with diabetes for 6 months to 3 years; group 2 (n=5), with the disease for 5–10 years; and group 3 (n=7), with diabetes for more than 10 years. VIP immunoreactivity (IR) and PGP-9.5-IR were significantly reduced around sweat glands (P <0.005) in groups 2 and 3. Epidermal CGRP-IR and PGP-9.5-IR were significantly reduced in group 3 (P <0.05). Twenty-eight per cent (5/18) of all patients showed high VIP-IR around sweat glands (>95 per cent confidence limits of controls) and all of these patients had diabetes for less than 3 years. Conversely, 55 per cent (10/18) of patients had low VIP-IR (<5 per cent confidence limit of controls). The latter, compared with the former, showed a significantly longer duration of diabetes (Fisher exact test P=0·002), presence of clinical autonomic neuropathy (Fisher exact test P=0.04), and a reduced sural nerve conduction velocity (Fisher exact test P=0.04). These results suggest that quantitative immunohistochemical analysis of peptide-containing cutaneous nerves allows an objective evaluation of nerve fibre alterations at early stages of diabetes than is currently possible with neurophysiological functional tests.  相似文献   
8.
T-cell homeostasis is regulated by several molecules; among these, interleukin (IL)-7 plays an essential role in the survival and homeostatic proliferation of peripheral naive T cells. In a previous study, we investigated whether human mesenchymal stromal cells (MSCs) could be engineered with the IL-7 gene to produce functional level of this cytokine. In the present study, we analyzed the impact of different quantities of IL-7 produced by MSCs on the survival and proliferation of a negative immunoselected naive (CD3(+)/CD45RA(+)) T-cell population. Co-cultivation of peripheral naive T cells with MSCs producing low (16 pg/mL) or high (1000 pg/mL) IL-7 levels or in the presence of exogenous IL-7 (0.01 ng/mL and 100 ng/mL) maintained the CD3(+)/CD45RA(+) naive T-cell phenotype. Chemokine receptor CCR7(+) expression was also maintained among this T-cell population. Naive T-cell molecular characteristics were maintained as assessed by the Vbeta spectratyping complexity score, which showed the maintenance of a broad T-cell repertoire. No Th1 or Th2 differentiation was observed, as assessed by interferon-gamma or IL-4 accumulation. In contrast, only MSCs producing high amounts of IL-7 caused increased activation (CD25 31.2% +/- 12% vs 10% +/- 3.5%; P < .05), proliferation (CD71 17.8+/-7% vs 9.3%+/-3, P < .05), apoptosis (assessed by annexin V: 18.6% +/- 5% vs 14.9% +/- 2.6%; P > .05), and the phase S cell cycle (15% vs 6.9%, P > .05). Exogenous IL-7 exhibited no significant effect. In conclusion, we demonstrated that IL-7 produced by MSCs has a dose-independent effect on naive T-cell survival while exerting a dose-dependent effect on activation/proliferation. Due to the continuous production of IL-7 by engineered cells, our system is more efficacious than exogenous IL-7.  相似文献   
9.
Chromosome analysis by Q, R, and C banding was performed in a case diagnosed clinically as gonadal dysgenesis and the karyotype was shown to be 46,X,Xt(qter leads to p221::p223 leads to qter). Localisation of the breakpoints in the fused X chromosomes and replication studies have led to a hypothesis on the origin of the translocation. A comparison of clinical and cytogenetical findings in this and other published cases has also been made in an attempt to detect some phenotype/karyotype correlations.  相似文献   
10.
The trisomy 8 found in malignancies may derive from a constitutional trisomy 8 mosaicism (CT8M), and in these cases the trisomy itself may be regarded as the first mutation in a multistep carcinogenetic process. To assess the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8, an informative sample of 14 patients was collected. The data ascertained included chromosome analyses of fibroblast cultures and of PHA-stimulated blood cultures in patients with normal blood differential count, as well as possible CT8M clinical signs. One patient showed trisomy 8 in all cell types analyzed and undoubtedly has a CT8M; a second patient consistently showed trisomy 8 in PHA-stimulated blood cultures when no immature myeloid cells were present in blood and should be considered as having CT8M; a third patient, with Philadelphia-positive chronic myelocytic leukemia, was more difficult to interpret, but the possibility that she had CT8M is likely. A few clinical signs of CT8M were also present in these three patients. Our data indicate that the frequency of CT8M in hematological dysplastic and neoplastic disorders with trisomy 8 is approximately 15-20%.  相似文献   
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