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Lymphocyte-predominant Hodgkin’s lymphoma (LPHL) differs in histologic and clinical presentation from classical Hodgkin’s lymphoma (cHL). Treatment of LPHL patients using standard Hodgkin’s lymphoma protocols leads to complete remission in more than 95% of patients. Survival and freedom from treatment failure are substantially worse in advanced-stage patients than for early-stage patients. Thus, patients in advanced stages and those in early stages with unfavorable risk factors should be treated similar to those with cHL. In contrast, patients with early-stage LPHL without risk factors might be sufficiently treated with reduced-intensity programs having less severe adverse effects. As a result, treatment of early LPHL is rather heterogeneous, including radiotherapy using extended-fleld technique, involved-fleld radiotherapy (IF-RT), combined-modality treatment, and, more recently, monoclonal antibodies. Watch-and-wait strategy plays an important role in pediatric oncology, to avoid adverse effects associated with therapy. IF-RT seems to be emerging as a treatment of choice for patients with stage IA LPHL; most larger study groups, such as the German Hodgkin Study Group and the European Organisation for Research and Treatment of Cancer, have adopted IF-RT as the treatment of choice for these patients.  相似文献   
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We have reviewed the incidence of cisplatin-induced anaemia in patients affected with solid tumours treated with at least three courses of first-line cisplatincontaining regimens. In our experience, a low percentage (5%) of patients required transfusions of red blood cells. We think it is of the utmost importance to adopt uniform criteria in monitoring and treatment of patients at risk of developing cisplatin anaemia and to identify subsets of patients to eventually treat with erythropoietin.  相似文献   
4.
In order to assess what different health care workers (mainly physicians and nursing staff) know about the reporting of communicable diseases, with special emphasis on diseases that must be urgently reported, four groups were interviewed about this health information system (91 persons, who took part in different Public Health Seminars during the periods 1989-90 and 1990-91). The total mean score was 16.6 +/- 5.2, in a quantitative scale ranging from 0 to 27 points. Cholera was the communicable disease with the highest percentage of correct answers concerning the knowledge of its reporting (100% in two groups), while typhus was the disease with the lowest percentage (23%). The diversity of the results within the study groups suggests that it is necessary to insist on a continuous training on epidemiological surveillance and communicable diseases within Public Health activities in Catalonia.  相似文献   
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Lactoferrin, a member of the transferrin family of approximately 80 kDa, consists of a single polypeptide chain folded in two symmetric, globular lobes (N- and C-lobes), each able to bind one ferric ion. This glycoprotein, found in physiological fluids of mammals, plays an important role in immune regulation and in defense mechanisms against bacteria, fungi, parasites, and viruses. Although the antiviral activity of lactoferrin is one of the major biological functions of such protein, the mechanism of action is still under debate. We have investigated both the role of tryptic fragments of bovine lactoferrin and the mechanism of lactoferrin antiviral effect toward adenovirus infection in HEp-2 cells. The results obtained demonstrated that the anti-adenovirus activity of lactoferrin is mediated by the N-terminal half of the protein as the N-lobe was able to inhibit adenovirus infection, even if at lower extent than undigested lactoferrin, whereas C-lobe was ineffective. The results also showed that the anti-adenovirus action of lactoferrin and of its N-terminal peptide lactoferricin took place on virus attachment to cell membrane, mainly through competition for common glycosaminoglycan receptors. The data provide evidence that the anti-adenovirus activity of lactoferrin is mediated mainly by the cluster of positive charges at the N-terminus of whole molecule and that the N-terminal peptide lactoferricin alone is sufficient to prevent infection.  相似文献   
7.
Anaplastic large cell lymphomas are associated with chromosomal aberrations involving the anaplastic lymphoma kinase (ALK) gene at 2p23 that result in the expression of novel chimeric ALK proteins with transforming properties. In most of these tumors, the t(2;5)(p23;q35) generates the NPM-ALK fusion gene. However, several studies have now demonstrated that genes other than NPM may be fused to the ALK gene. We have recently described two different ALK rearrangements involving the TRK-fused gene (TFG) in which the same portion of ALK was fused to different length fragments of the 5' TFG region. These two rearrangements encoded chimeric proteins of 85 kd (TFG-ALK(S)) and 97 kd (TFG-ALK(L)), respectively. In this study, we have identified a new ALK rearrangement in which the catalytic domain of ALK was fused to a larger fragment of the TFG gene (TFG-ALK(XL)), encoding for a fusion protein of 113 kd. Genomic analysis of these three TFG-ALK rearrangements revealed that the TFG breakpoints occur at introns 3, 4, and 5, respectively, whereas the ALK breakpoints always occur in the same intron. No homologous regions or known recombination sequences were found in these regions. Transfection experiments using NIH-3T3 fibroblasts showed a similar transforming efficiency of TFG-ALK variants compared with NPM-ALK. In addition, in common with NPM-ALK, the TFG-ALK proteins formed stable complexes with the signaling proteins Grb2, Shc, and PLC-gamma. In conclusion, these findings indicate that the TFG may use a variety of intronic breakpoints in ALK rearrangements generating fusion proteins of different molecular weights, but with similar transforming potential than NPM-ALK.  相似文献   
8.
INK4a/ARF locus codes for two different proteins, p16(INK4a) and p14(ARF), involved in cell cycle regulation. p14(ARF) is considered an upstream regulator of p53 function. To determine the role of these genes in the pathogenesis of human non-Hodgkin's lymphomas we have analyzed exon 1beta, 1alpha, and 2 of the INK4a/ARF locus and p53 gene aberrations in 97 tumors previously characterized for p16(INK4a) alterations. p53 alterations were detected in four of 51 (8%) indolent lymphomas but in 15 of 46 (33%) aggressive tumors. Inactivation of p14(ARF) was always associated with p16(INK4a) alterations. Exon 1beta was concomitantly deleted with exon 1alpha and 2 in eight tumors. One additional lymphoblastic lymphoma showed deletion of exon 1alpha and 2 but retained exon 1beta. No mutations were detected in exon 1alpha and 1beta in any case. Two of the three mutations detected in exon 2 caused a nonsense mutation in the p16(INK4a) reading frame and a missense mutation in the ARF reading frame involving the nucleolar transport domain of the protein. The third mutation was a missense mutation in the p16(INK4a) reading frame, but it was outside the coding region of p14(ARF). Aggressive lymphomas with p14(ARF) inactivation and p53 wild type showed a significantly lower p53 protein expression than tumors with no alteration in any of these genes. In this series of tumors, inactivation of the INK4a/ARF locus mainly occurred in tumors with a wild-type p53 gene because only two lymphomas showed simultaneous aberrations in these genes. Tumors with concomitant alterations of p16(INK4a) and p14(ARF)/p53 genes seem to exhibit a worse clinical behavior than lymphomas with no alterations or isolated inactivation of any of these genes. These findings indicate that p14(ARF) genetic alterations occur in a subset of aggressive NHLs, but they are always associated with p16(INK4a) aberrations. Concomitant disruption of p16(INK4a) and p14(ARF)/p53 regulatory pathways may have a cooperative effect in the progression of these tumors.  相似文献   
9.
We analyzed the characteristics of the inflammatory response occurring in blood during pulmonary infections in human immunodeficiency virus (HIV)-infected patients. A prospective study of consecutive hospital admissions of HIV-infected patients with new-onset radiologic pulmonary infiltrates was carried out in a tertiary university hospital from April 1998 to May 2001. Plasma cyclic AMP receptor protein (CRP), interleukin 1β (IL-1β), IL-6, IL-8, IL-10, and tumor necrosis factor alpha (TNF-α) levels were determined at the time of admission and 4, 5, and 6 days later. Patients were included in a protocol addressed to study etiology and outcome of disease. A total of 249 episodes of infection were included, with the main diagnoses being bacterial pneumonia (BP) (118 episodes), Pneumocystis carinii pneumonia (PCP) (41 episodes), and mycobacteriosis (36 episodes). For these three patient groups, at the time of admission the median CRP and cytokine levels were as follows: CRP, 10.2, 3.8 and 5 mg/dl, respectively (P = 0.0001); IL-8, 19, 3, and 2.9 pg/ml (P = 0.045); and TNF-α, 46.4, 44, and 75 pg/ml, respectively (P = 0.029). There were no significant differences in levels of IL-1β, IL-6, or IL-10 among the patient groups. A total of 23 patients died. At the time of admission, HIV-infected patients with BP had higher plasma CRP and IL-8 levels than did PCP and mycobacteriosis patients. TNF-α levels were higher in patients with mycobacteriosis. An elevated IL-8 level (>61 pg/ml) at the time of admission was an independent factor associated with higher mortality (odds ratio, 12; 95% confidence interval, 1.2 to 235.5).  相似文献   
10.
BACKGROUND: Raloxifene hydrochloride is a synthetic non-steroidal drug used for the prevention and treatment of post-menopausal osteoporosis. Pre-clinical and clinical data have shown that raloxifene may have a beneficial effect on leiomyomas. The aim of this prospective single-blind, randomized, placebo-controlled clinical trial was to evaluate the effectiveness of the addition of raloxifene to GnRH analogues on uterine, leiomyoma, and non-leiomyoma sizes, and on the occurrence of leiomyoma-related symptoms. METHODS: After randomization using a computer-generated list, 100 pre-menopausal women with symptomatic uterine leiomyomas received either leuprolide acetate depot plus raloxifene 60 mg daily (group A) or leuprolide plus placebo tablet (group B) for six cycles of 28 days. At baseline and after treatment, uterine, leiomyoma and non-leiomyoma sizes, and leiomyoma-related symptoms were evaluated for each woman. Analysis was by intention-to-treat method. RESULTS: After six cycles of treatment, a significant decrease in uterine, leiomyoma, and non-leiomyoma sizes was detected in both groups in comparison with baseline. At the same time, no significant difference in uterine and non-leiomyoma sizes was observed between the groups. Leiomyoma sizes were significantly (P < 0.05) lower in group A than in group B. No difference was observed in leiomyoma-related symptoms between groups throughout the study period. CONCLUSIONS: In women treated with GnRH analogue, the raloxifene administration induces a higher reduction of leiomyoma sizes.  相似文献   
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