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21.
Rybicki  AC; Qiu  JJ; Musto  S; Rosen  NL; Nagel  RL; Schwartz  RS 《Blood》1993,81(8):2155-2165
Red blood cell (RBC) protein 4.2 deficiency is often associated with a moderate nonimmune hemolytic anemia, splenomegaly, and osmotically fragile RBCs resembling, but not identical to, hereditary spherocytosis (HS). In the Japanese type of protein 4.2 deficiency (protein 4.2Nippon), the anemia is associated with a point mutation in the protein 4.2 cDNA. In this report, we describe a patient with moderate and apparently episodic nonimmune hemolytic anemia with splenomegaly, spherocytosis, osmotically fragile RBCs, reduced whole cell deformability, and abnormally dense cells. Sodium dodecyl sulfate- polyacrylamide gel electrophoresis analysis of the proposita's RBC membrane proteins showed an 88% deficiency of protein 4.2 and a 30% deficiency of glyceraldehyde-3-phosphate dehydrogenase (band 6). Structural and molecular analyses of the proposita's protein 4.2 were normal. In contrast, limited tryptic digestion of the proposita's band 3 showed a homozygous abnormality in the cytoplasmic domain. Analysis of the pedigree disclosed six members who were heterozygotes for the band 3 structural abnormality and one member who was a normal homozygote. Direct sequence analysis of the abnormal band 3 tryptic peptide suggested that the structural abnormality resided at or near residue 40. Sequence analysis of the proposita's band 3 cDNA showed a 232G-->A mutation resulting in a 40glutamic acid-->lysine substitution (band 3Montefiore). Allele-specific oligonucleotide hybridization was used to probe for the mutation in the pedigree, showing that the proposita was homozygous, and the pedigree members who were heterozygous for the band 3 structural abnormality were also heterozygous for the band 3Montefiore mutation. The band 3Montefiore mutation was absent in 26 chromosomes from race-matched controls and in one pedigree member who did not express the band 3 structural abnormality. In coincidence with splenectomy, the proposita's anemia was largely corrected along with the disappearance of most spherocytes and considerable improvements of RBC osmotic fragility, whole cell deformability, and cell density. We conclude that this hereditary hemolytic anemia is associated with the homozygous state for band 3Montefiore (40glutamic acid-->lysine) and a decreased RBC membrane content of protein 4.2. We speculate that band 3 structural abnormalities can result in defective interactions with protein 4.2 and band 6, and in particular, that the region of band 3 containing 40glutamic acid is involved directly or indirectly in interactions with these proteins.  相似文献   
22.
OBJECTIVE: To investigate the impact of official recommendations regarding the management of latent tuberculosis (TB) infection on the rate of active TB in patients receiving treatment with tumor necrosis factor (TNF) antagonists. METHODS: Data on active TB rates and on screening and treatment of latent TB infection were extracted from the BIOBADASER (Spanish Society of Rheumatology Database on Biologic Products), a registry of patients with rheumatic conditions treated with TNF antagonists. The rates of active TB among the BIOBADASER patients were compared with those in the background Spanish population, and BIOBADASER patients with rheumatoid arthritis (RA) were compared with a cohort of RA patients from the EMECAR (Morbidity and Clinical Expression of Rheumatoid Arthritis) study who were not treated with TNF antagonists and were followed up for 5 years. RESULTS: Active TB developed in 34 patients, of whom 32 started taking TNF antagonists prior to the official recommendations on latent TB infection (pre-OR) and 2 began treatment after the recommendations were issued (post-OR). All cases of TB occurred during treatment with infliximab, and 28 of these patients had RA. Pre-OR, the active TB rate in BIOBADASER patients was 20.9-fold higher than in the background Spanish population, while RA patients in the BIOBADASER had rates 22.6- and 6.2-fold higher than the background and EMECAR populations, respectively. Post-OR, 324 patients with a tuberculin skin test result > or =5 mm and/or chest radiograph findings suggestive of past TB were treated for 9 months with isoniazid (INH). Post-OR, active TB rates among the BIOBADASER patients decreased by 78% (incidence risk ratio [IRR] 0.22, 95% confidence interval [95% CI] 0.03-0.88; P = 0.008), while among RA patients in the BIOBADASER, the rate dropped by 83% and reached the EMECAR rate (IRR 1.0, 95% CI 0.02-8.2). There were no INH treatment-related hospitalizations or deaths. CONCLUSION: Strategies to treat latent TB infection that are tailored to the at-risk population can effectively and safely lessen the likelihood of active TB in patients treated with TNF antagonists.  相似文献   
23.
Long-term bone marrow cultures (LTBMC) from patients with multiple myeloma (MM) and normal donors were analyzed for immunophenotype and cytokine production. Both LTBMC adherent cells from myeloma and normal donor origin expressed CD10, CD13, the adhesion molecules CD44, CD54, vascular cell adhesion molecule 1, very late antigen 2 (VLA-2), and VLA- 5, and were positive for extracellular matrix components fibronectin, laminin, and collagen types 3 and 4. LTBMC from myeloma patients and normal donors spontaneously secreted interleukin-6 (IL-6). However, levels of IL-6 correlated with the stage of disease; highest levels of IL-6 were found in LTBMC from patients with active myeloma. To identify the origin of IL-6 production, LTBMC from MM patients and normal donors were cocultured with BM-derived myeloma cells and cells from myeloma cell lines. IL-6 was induced by plasma cell lines that adhered to LTBMC such as ARH-77 and RPMI-8226, but not by nonadhering cell lines U266 and FRAVEL. Myeloma cells strongly stimulated IL-6 secretion in cocultures with LTBMC adherent cells from normal donors and myeloma patients. When direct cellular contact between LTBMC and plasma cells was prevented by tissue-culture inserts, no IL-6 production was induced. This implies that intimate cell-cell contact is a prerequisite for IL-6 induction. Binding of purified myeloma cells to LTBMC adherent cells was partly inhibited by monoclonal antibodies against adhesion molecules VLA-4, CD44, and lymphocyte function-associated antigen 1 (LFA-1) present on the plasma cell. Antibodies against VLA-4, CD29, and LFA-1 also inhibited the induced IL-6 secretion in plasma cell-LTBMC cocultures. In situ hybridization studies performed before and after coculture with plasma cells indicated that LTBMC adherent cells produce the IL-6. These results suggest that the high levels of IL-6 found in LTBMC of MM patients with active disease are a reflection of their previous contact with tumor cells in vivo. These results provide a new perspective on tumor growth in MM and emphasize the importance of plasma cell-LTBMC interaction in the pathophysiology of MM.  相似文献   
24.
25.
OBJECTIVE: The aim was to assess the effects of chronic regional denervation of the ischaemic myocardium on reperfusion arrhythmias in a model with sparse coronary collateral circulation. METHODS: Baseline ventricular refractoriness and epicardial activation times were measured together with reperfusion arrhythmias after 15 min (I-15') or 30 min (I-30') of left anterior descending coronary artery occlusion in 38 barbiturate anaesthetised open chest pigs. Twenty pigs (11 in I-15' and nine in I-30') had a chronic (two week) denervation of the left anteroseptal region, whereas 18 pigs (10 in I-15' and eight in I-30') were sham operated (non-denervated) controls. Denervation was induced by pericoronary application of phenol and verified by absence of adrenergic histofluorescence. RESULTS: As compared with controls, denervated pigs showed: (1) longer activation times: 20.3 (SD 5.2) ms v 16.5 (4.6) ms, p < 0.001; (2) slightly longer refractory periods: 348(28) ms v 334(27) ms; (3) a tendency to lower postreperfusion ectopic activity: ectopic beats divided by time free of ventricular tachycardia: 0.13(0.19) v 0.34(0.40) in I-15', and 0.21(0.24) v 0.39(0.44) in I-30'; (4) slower ventricular tachycardia in I-30': 140(29) beats.min-1 v 185(29) beats.min-1, p < 0.009; and (5) comparable incidence of postreperfusion ventricular fibrillation: 4/11 pigs v 2/10 in I-15', and 5/9 v 4/8 in I-30'. CONCLUSIONS: Selective chronic denervation of the ischaemic myocardium was unable to protect against malignant reperfusion arrhythmias in hearts with human-like coronary collaterals. This was confirmed at two ischaemic periods known to produce progressive catecholamine accumulation and increased adrenoceptor density in the ischaemic myocardium.  相似文献   
26.
Hepatitis B virus DNA (HBV-DNA) in serum was studied in 67 anti-HBe patients using dot-blot hybridization, a modified technique and polymerase chain reaction (PCR). All patients had abnormal aminotransferase (ALT) levels. Serum HBV-DNA was detected in 14/67 cases by dot-blot and in 39/67 (DNA probe) and 45/67 (RNA probe) using the modified technique. The RNA probe was more sensitive than the DNA probe when they were compared, using serial dilutions of HBV-DNA of known concentration (0.1 pg vs 1 pg, respectively). HBV-DNA was found by PCR in 57/67 patients. Ten patients were negative to serum HBV-DNA. The ALT level was significantly higher in patients with serum HBV-DNA by dot-blot as compared to those who had serum HBV-DNA by the modified technique and PCR. With respect to the presence of anti-HCV, 6/67 had anti-HCV confirmed by RIBA test. These 6 patients had serum HBV-DNA. The route of acquisition of HBV infection in anti-HCV positive patients was by parenteral exposure in 67% of the cases and 15% in HCV negative (p less than 0.05). All patients were negative to nonorganic specific autoantibodies. In summary, most of the anti-HBe patients (85%) had viral replication. HCV superinfection plays a minor role in the activity of liver disease.  相似文献   
27.
Systemic lupus erythematosus (SLE) is an autoimmune systemic disease caused as a result of an imbalance of Th1‐/Th2‐type cytokines. The soluble form of CD30 (CD30s) released from peripheral blood cells has been described as a marker of active disease in Th2‐type immune response as in SLE. However, the expression of CD30 on CD3 T lymphocytes from patients with SLE has not been studied yet. Therefore, we have addressed our study to attempt this issue, studying CD30 expression by flow cytometry on CD3 T lymphocytes and CD4/CD8 subsets in samples from SLE patients mainly with lupus nephritis. In parallel, we have determined the production of the cytokines IL‐4 (Th2), IFNγ (Th1), IL‐10 and TGFβ by intracellular staining. Differences between positive CD30 T cells in healthy controls and patients with SLE were found, with a higher percentage of CD30‐expressing T cells in patients with SLE (= 0.001). In contrast to healthy controls, CD30 was mainly expressed on CD8 T cells from patients with SLE. The intracellular cytokine staining showed that TGFβ is the main cytokine expressed in CD3 T cells from patients with SLE. In addition to this, we have found a positive correlation between CD30‐expressing T cells and IL‐4, IFNγ, and immunosuppressive cytokines (IL‐10 and TGFβ) (< 0.05). These results suggest that CD30 could play a role in the pathogenesis of SLE and its expression on CD3 T lymphocytes is not restricted only to Th2‐type response.  相似文献   
28.
AIM: To evaluate the effects of two different doses of sugammadex after maintenance anesthesia with sevofluorane and remifentanil and deep rocuroniuminduced neuromuscular blockade(NMB).METHODS: Patients between 20 and 65 years of age, with American Society of Anesthesiologists physical status classification Ⅰ-Ⅱ, undergoing gynecological surgery were included in a prospective, comparative and randomized study. NMB was induced with an injection of 0.6 mg/kg of rocuronium followed by continuous infusion of 0.3-0.6 mg/kg per hour to maintain a deep block. Anesthesia was maintained with sevofluorane and remifentanil. Finally, when surgery was finished, a bolus of 2 mg/kg(group A) or 4 mg/kg(group B) of sugammadex was applied when the NMB first response in the train-of-four was reached. The primary clinical endpoint was time to recovery to a train-of-four ratio of 0.9. Other variables recorded were the time until recovery of train-of-four ratio of 0.7, 0.8, hemodynamic variables(arterial blood pressure and heart rate at baseline, starting sugammadex, and minutes 2, 5 and 10) and adverse events were presented after one hour in the post-anesthesia care unit.RESULTS: Thirty-two patients were included in the study: 16 patients in group A and 16 patients in group B. Only 14 patients each group were recorded because arterial pressure values were lost in two patients from each group in minute 10. The two groups were comparable. Median recovery time from starting of sugammadex administration to a train-of-four ratio of 0.9 in group A and B was 129 and 110 s, respectively.The estimated difference in recovery time between groups was 24 s(95%CI: 0 to 45 s, Hodges-Lehmann estimator), entirely within the predefined equivalence interval. Times to recovery to train-of-four ratios of 0.8(group A: 101 s; group B: 82.5 s) and 0.7(group A: 90 s; group B: 65 s) from start of sugammadex administration were not equivalent between groups. There was not a significant variation in the arterial pressure and heart rate values between the two groups and none of the patients showed any clinical evidence of residual or recurrent NMB. CONCLUSION: A dose of 2 mg/kg of sugammadex after continuous rocuronium infusion is enough to reverse the NMB when first response in the Train-OfFour is reached.  相似文献   
29.
Okamoto  S; Olson  AC; Berdel  WE; Vogler  WR 《Blood》1988,72(5):1777-1783
Ether lipids (EL) and hyperthermia have been shown to possess a relatively selective cytotoxicity to leukemic cells. In this study, the combined effects of EL (ET-18-OCH3, ET-16-NHCOCH3, or BM 41.440) and hyperthermia on the growth of hematopoietic progenitors, myeloid leukemic cell lines, and leukemic cells obtained from patients with acute myeloid leukemia (AML) were examined to determine if this combination resulted in a greater selective killing of leukemic cells than that achieved by either EL or heat alone. When the cells were treated simultaneously with EL (50 micrograms/mL) and hyperthermia (42 degrees C) for one hour, the killing of leukemic cell line cells was enhanced considerably. Among the three EL, however, the combination of ET-18-OCH3 and heat seemed to be the most cytotoxic to leukemic cell line cells with no effect on the growth of hematopoietic progenitors. An increase in the duration of treatment with ET-18-OCH3 to four hours with heat added during the last hour resulted in a further reduction of leukemic cell line cells while sparing 50% of hematopoietic progenitors after cryopreservation. The combined treatment with ET-18-OCH3 and heat also inhibited the growth of leukemic progenitors obtained from AML patients by 97% to 100%. These data indicate that the combined treatment with EL and hyperthermia might offer an efficient means to eliminate myeloid leukemic cells in vitro.  相似文献   
30.
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