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41.
We treated 51 patients with advanced malignant lymphoma refractory to conventional therapy with methyl-glyoxal-bis(guanylhydrazone) (methyl- GAG) at doses ranging from 400 to 800 mg/sq m. Therapy was started on a weekly schedule and was switched to every other week in responding patients at the onset of toxicity. Partial responses were observed in 6 of 13 evaluable patients with Hodgkin's disease (46%), 5 of 10 patients with diffuse poorly differentiated lymphocytic lymphoma (50%), 2 of 4 patients with nodular poorly differentiated lymphocytic lymphoma (50%), and 3 of 13 patients with diffuse histiocytic lymphoma (23%). Two of six patients with mycosis fungoides showed objective improvement in cutaneous disease. Toxicity was generally mild and included muscular weakness, myalgia, mucositis, and diarrhea; two patients developed bronchospasm following drug infusions. We conclude that methyl-GAG has major antitumor activity when administered on this schedule to patients with advanced malignant lymphoma. The low degree of toxicity, unique mechanism of action, and minimal myelosuppressive effects suggest that methyl-GAG will prove useful in future trials of combination chemotherapy regimens for the treatment of lymphoma. 相似文献
42.
BACKGROUND AND OBJECTIVES: Autoimmune lymphoproliferative syndrome (ALPS), is an inherited disorder characterized by defective lymphocyte apoptosis, lymphadenopathy, splenomegaly, accumulation of T-cell receptor (TCR)-alphabeta+ CD4- CD8- T cells (double-negative T cells) and autoimmunity. We investigated the incidence and nature of neutrophil and platelet antibodies in patients with ALPS. MATERIALS AND METHODS: Sera from 26 patients with ALPS were tested for neutrophil antibodies by granulocyte immunofluorescence, granulocyte agglutination and monoclonal antibody immobilization assays of granulocyte antigens, and for platelet antibodies using a solid-phase antibody-detection system. RESULTS: Neutrophil antibodies were detected in 46% of patients with ALPS. Antibody specificity could be defined in eight of the 12 patients with neutrophil antibodies. Among these eight patients, four had antibodies directed against more than one antigen. Overall, 14 antibodies directed to specific antigens were identified: three were directed to the HNA-1a antigen of FcgammaRIIIb; two to the HNA-1b antigen of Fcgamma-RIIIb; two to epitopes common to all FcgammaRIIIb molecules; four to the HNA-2a antigen of the NB1 glycoprotein; and three to neutrophil beta2 integrins. Platelet antibodies were detected in 35% of patients with ALPS. No antibody specificities were identified among the platelet antibodies. There was no association between the detection of neutrophil antibodies and a history of clinical neutropenia, or between the detection of platelet antibodies and a history of clinical thromobocytopenia. CONCLUSIONS: Neutrophil and platelet antibodies are important markers of ALPS, but do not always cause clinical cytopenias. The specificities of neutrophil antibody were similar to those found in children with autoimmune neutropenia but without ALPS. 相似文献
43.
STUDY OBJECTIVES: To study the incidence of upper airway obstruction, as measured on the flow volume loop (FVL), in patients with bulky mediastinal Hodgkin's disease; to correlate the FVL with CT of the chest; and to follow the changes in the FVL after treatment of the tumor. DESIGN: Retrospective study of pulmonary function tests (PFTs) and chest CTs performed as part of a clinical trial for Hodgkin's disease. SETTING: Memorial Sloan-Kettering Cancer Center, a comprehensive cancer care center. PATIENTS: Twenty-five patients (15 men and 10 women; age range, 20 to 57 years) with bulky mediastinal Hodgkin's disease enrolled in a clinical trial of chemotherapy followed by external beam radiation therapy. MEASUREMENTS AND RESULTS: Fourteen of 25 patients (56%) had an abnormal FVL prior to therapy; after chemotherapy, only 7 of 25 patients (28%) had an abnormal FVL. The abnormal patterns seen were either those typical of fixed obstruction or variable extrathoracic obstruction. No patient had a pattern typical of variable intrathoracic obstruction. On chest CT scan, 16 patients had grade-I tracheal deformity; 6 had grade-II deformity, and 3 had grade-III deformity. All three patients with grade-III deformity had a fixed obstruction pattern, as did three patients with a grade-I pattern. Patients with a fixed pattern on FVL had significant decreases in inspiratory and expiratory flow rates. CONCLUSION: FVL abnormalities suggesting upper airway obstruction occurred in > 50% of patients with bulky mediastinal Hodgkin's disease. A fixed pattern of obstruction was associated with the lower flow rates and severe tracheal distortion on CT; these patients may warrant special attention prior to general anesthesia or invasive procedures. Asymptomatic patients with abnormal FVLs but normal tracheal profiles need not undergo extensive evaluation. No patients showed the expected pattern typical of intrathoracic obstruction, but rather the major effect was on the inspiratory loop. The authors speculate on the mechanism for this unexpected finding. 相似文献
44.
S E Straus J Owens W T Ruyechan H E Takiff T A Casey G F Vande Woude J Hay 《Proceedings of the National Academy of Sciences of the United States of America》1982,79(4):993-997
Varicella-zoster virus (VZV) DNA was cleaved with restriction endonuclease EcoRI, and most of the resulting fragments were successfully cloned in the phage vector lambda gtWES . lambda B. Double digestions of cloned fragments with EcoRI and BamHI and hybridizations to blot-transferred BamHI digests of VZV DNA were used to construct a physical map of the genome. The molecular termini of the DNA were identified by restriction enzyme analysis after exonuclease III digestion. The data indicate that VZV DNA exists in two isomeric forms that differ by inversion of one short terminal genome segment. Electron microscopic studies revealed that the short genome segment consists of a terminal revealed that the short genome segment consists of a terminal sequence of about 3.4 X 10(6) daltons that is separated from an internal inverted repeat of itself by a 5.8 X 10(60)-dalton unique DNA segment. 相似文献
45.
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47.
Lee C Straus WL Balshaw R Barlas S Vogel S Schnitzer TJ 《Arthritis and rheumatism》2004,51(5):746-754
OBJECTIVE: To perform a meta-analysis comparing the efficacy and safety of recommended dosages of nonsteroidal antiinflammatory drugs (NSAIDs), including cyclooxygenase 2 inhibitors, versus acetaminophen in the treatment of symptomatic hip and knee osteoarthritis. METHODS: Medline and EMBASE searches were performed for original clinical trials directly comparing NSAIDs with acetaminophen. A standardized form was used to abstract all data, including outcome measures of pain at rest, walking pain, and dropouts due to adverse effects. Inverse-variance-weighted mean differences (WMDs) and 95% confidence intervals (95% CI) for pain measures were determined for treatment groups. Odds ratios (ORs) and 95% CIs were calculated for withdrawals due to adverse events. Results were compared using a random effects model. RESULTS: Seven articles met inclusion criteria with sufficient data for analysis. Participants had a mean age of 61.1 years and 71.1% were women. Test of heterogeneity was not significant for either rest (P = 0.73) or walking (P = 0.76) pain. The scores for overall pain at rest (WMD -6.33 mm on a 100-mm visual analog scale [VAS], 95% CI -9.24, -3.41) and walking pain (WMD -5.76 mm on a 100-mm VAS, 95% CI -8.99, -2.52) favored the NSAID-treated group. Although NSAIDs elevated the risk of withdrawals due to adverse events, the difference was not statistically significant (OR 1.45, 95% CI 0.93, 2.27). CONCLUSION: NSAIDs are statistically superior in reducing rest and walking pain compared with acetaminophen for symptomatic osteoarthritis. Safety, measured by discontinuation due to adverse events, was not statistically different between NSAID- and acetaminophen-treated groups. 相似文献
48.
Arends RJ Rotllant J Metz JR Mancera JM Wendelaar Bonga SE Flik G 《The Journal of endocrinology》2000,166(2):427-435
MSH is a pituitary hormone derived by post-translational processing from POMC and involved in stress and background adaptation. N-terminal acetylation of MSH to monoacetyl alpha-MSH or diacetyl alpha-MSH increases the bioactivity of the peptide. The aim of this study was to characterize alpha-MSH acetylation in the sea bream (Sparus aurata L.) pituitary gland in response to the stressors air exposure and confinement, as well as in fish adapted for 15 days to a white, gray or black background. Pituitary homogenates were purified by reversed-phase HPLC (RP-HPLC). The alpha-MSH content of fractions was measured by RIA. Immunoreactive RP-HPLC fractions were further analyzed by electrospray mass spectrometry and the peptide sequence determined as SYSMEHFRWGKPV-NH2. In the pituitary gland of sea bream, des-, mono- and diacetyl alpha-MSH were identified. Then plasma alpha-MSH levels were measured in sea bream adapted to different backgrounds. Surprisingly, we found the highest plasma alpha-MSH levels in white-adapted as compared with black-adapted sea bream with intermediate values for gray-adapted fish. This observation is in contrast with results that have been obtained in eel, trout or terrestrial vertebrates. Next, des-, mono- and diacetyl alpha-MSH forms were measured in homogenates of the pituitary gland and in plasma of sea bream exposed to air, to confinement, or to different backgrounds. Monoacetyl alpha-MSH was the predominant form in all control and experimental groups. The lowest content of monoacetyl alpha-MSH relative to des- and diacetyl alpha-MSH was found in white-adapted fish. Levels of des- and diacetyl alpha-MSH forms were similar under all conditions. We observed that monoacetyl alpha-MSH is the most abundant isoform in the pituitary gland after background adaptation, confinement and air exposure, in sea bream. These data indicate that the physiologically most potent isoform of alpha-MSH may vary from species to species. 相似文献
49.
Transforming growth factor beta (TGF-beta) is a potent and selective growth inhibitor of early hematopoietic progenitors and leukemic cells. The cellular mechanism(s) underlying this antiproliferative effect is, however, currently unknown. In the present study, we demonstrate that TGF-beta inhibits the expression of granulocyte-macrophage colony stimulating factor (GM-CSF), interleukin 3 (IL-3), and granulocyte-CSF (G-CSF) receptors on murine factor-dependent and independent hematopoietic progenitor cell lines without a significant change in receptor affinity. A maximum reduction in GM-CSF receptor numbers of 65% to 77% was observed by 96-hour incubation with TGF-beta. The TGF- beta induced trans-down-modulation of GM-CSF receptors was prolonged, noncytotoxic but reversible, and not due to endogenous production of GM- CSF. The TGF-beta induced reduction in CSF receptor numbers preceded TGF-beta's growth inhibitory action. In addition, the ED50 (1 to 10 pmol/L) for TGF-beta's CSF receptor modulatory and antiproliferative effect was similar. The effect of TGF-beta on cell surface CSF receptor expression was specific, because the expression of other cell surface proteins (Ly 5 and Ly 17) was not affected by TGF-beta treatment, and because other growth inhibitors (tumor necrosis factor and interferon) did not affect CSF receptor expression. These data suggest that the downregulation of the growth of hematopoietic progenitor cells by TGF- beta involves reducing the cell surface expression on growth factor receptors. 相似文献
50.
Expression of hybrid class I genes of the major histocompatibility complex in mouse L cells. 总被引:1,自引:2,他引:1 下载免费PDF全文
D S Straus I Stroynowski S G Schiffer L Hood 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(18):6245-6249
The class I genes of the major histocompatibility complex of the mouse can be divided into two categories: those encoding the transplantation antigens and those encoding the Qa and Tla antigens. The inbred BALB/c mouse has 28 potential Qa/Tla genes. The sites of tissue expression, developmental regulation, and functions of these genes are virtually unknown. We have used the technique of exon shuffling to construct hybrid genes between each of three Qa region genes (Q5, Q7, and Q8) and two other class I genes (H-2Ld and Q6). The hybrid genes have been transfected into mouse L cells, in which intact transplantation antigen genes generally are expressed and in which intact Qa genes generally are not expressed. Analysis of expression of the hybrid gene constructs indicates that the 5' half of two of the Qa genes (Q5 and Q8) can readily be expressed in the context of a hybrid molecule, whereas the 3' half prevents cell-surface expression. The exon shuffling approach described here will be useful in characterizing Qa/Tla genes and in identifying or producing new reagents to study the Qa/Tla gene products, their tissue distribution, their developmental stages of expression, and, ultimately, their functions. 相似文献