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81.
82.
In a second update of a systematic review, many new developments in the
combined drug treatment of rheumatoid arthritis (RA) are highlighted. In
early RA patients, step-down bridge therapy that includes corticosteroids
leads to much enhanced efficacy at acceptable or low toxicity. The effects
on joint damage may be persistent, but the symptomatic effects are probably
dependent on continued corticosteroid dosing. In late patients, cyclosporin
improves a suboptimal clinical response to methotrexate, and the triple
combination of methotrexate, sulphasalazine and hydroxychloroquine appears
to be clinically better than the components. Other combinations are either
untested, tested at low sample size, or show negative interaction. In view
of the low volume of evidence, most studies need confirmation by
replication.
相似文献
83.
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
84.
Activation of human platelets by immune complexes prepared with cationized human IgG 总被引:1,自引:0,他引:1
Schattner M; Lazzari M; Trevani AS; Malchiodi E; Kempfer AC; Isturiz MA; Geffner JR 《Blood》1993,82(10):3045-3051
The present study shows that the ability of soluble immune complexes (IC), prepared with human IgG and rabbit IgG antibodies against human IgG, to trigger platelet activation was markedly higher for IC prepared with cationized human IgG (catIC) compared with those prepared with untreated human IgG (cIC). CatIC induced platelet aggregation and adenosine triphosphate release in washed platelets (WP), gel-filtered platelets (GFP), or platelet-rich plasma (PRP) at physiologic concentrations of platelets (3 x 10(8)/mL) and at low concentrations of catIC (1 to 30 micrograms/mL). On the contrary, under similar experimental conditions, cIC did not induce aggregation in PRP, WP, or GFP. Low aggregation responses were only observed using high concentrations of both WP (9 x 10(8)/mL) and cIC (500 micrograms/mL). Interestingly, catIC were also able to induce platelet activation under nonaggregating conditions, as evidenced by P-selectin expression. Cationized human IgG alone did not induce platelet aggregation in PRP but triggered either WP or GFP aggregation. However, the concentration needed to induce these responses, was about eightfold higher than those required for catIC. The responses induced either by catIC or cationized human IgG were completely inhibited by treatment with heparin, dextran sulphate, EDTA, prostaglandin E1, or IV3, a monoclonal antibody against the receptor II for the Fc portion of IgG (Fc gamma RII). The data presented in this study suggest that IgG charge constitutes a critical property that conditions the ability of IC to trigger platelet activation. 相似文献
85.
Femoral capital osteonecrosis: MR finding of diffuse marrow abnormalities without focal lesions 总被引:13,自引:0,他引:13
Six painful hips in five patients were examined with magnetic resonance (MR) imaging and were found to have diffuse signal abnormalities in the marrow of the femoral head and neck, which extended into the intertrochanteric area in five cases. The abnormal regions were low in signal intensity on images obtained with a short repetition time (TR) and a short echo time (TE) and were isointense or hyperintense on long TR/TE images--findings that have been attributed by others to bone marrow edema. Edema was also seen in marrow just above the acetabulum in two cases. No focal abnormalities characteristic of osteonecrosis were seen. Osteonecrosis was subsequently shown to be present in all six femoral heads at core biopsy (three cases) or by subsequent development of focal MR abnormalities reported to be highly specific for osteonecrosis (three cases). The affected hips had been radiographically normal or subtly osteopenic and had shown intense radionuclide uptake in the femoral head at scintigraphy, with lesser abnormality in the neck and intertrochanteric region. Follow-up MR examinations of five of the six femoral heads showed the diffuse abnormalities to have been transient. Although diffuse MR abnormalities in the proximal femur are not specific, they may indicate the presence of osteonecrosis of the femoral head. 相似文献
86.
AC Davaine A Saraux S Prigent I Kupfer‐Bessaguet D Roswag P Plantin P Schoenlaub F Talarmin A Zagnoli L Misery 《Journal of the European Academy of Dermatology and Venereology》2008,22(12):1471-1477
Background Anti‐tumour necrosis factors (anti‐TNF) are more and more used, but the rate of skin adverse events is not known. Objective The aim was to assess the number of skin infections and other dermatoses in patients treated with anti‐TNFα. Patients and methods One hundred eighty‐seven patients suffering from rheumatoid arthritis or ankylosing spondylitis underwent a dermatological exam. Patients with anti‐TNF were compared with those without this treatment in a prospective transversal study. Results Among them, 59 patients were treated with anti‐TNFα and steroids were prescribed in 100 cases. There was no difference in the prevalence of skin infections or eczema or tumours. Skin drug reactions were observed in six patients. Infections by dermatophytes appear very frequent, approaching 70% in both groups. Conclusions This study shows that skin infections (or other skin diseases) are not more frequent in these patients. No differences were observed in infections (bacterial fungal, parasital or viral), tumours, psoriasis or the manifestations of atopic dermatitis. Nonetheless, a long‐term survey might be interesting, especially about skin tumours. 相似文献
87.
88.
AC Winter K Berger JE Buring & T Kurth 《Cephalalgia : an international journal of headache》2009,29(2):269-278
We evaluated the association of body mass index (BMI) with migraine and migraine specifics in a cross-sectional study of 63 467 women aged ≥ 45 years, of whom 12 613 (19.9%) reported any history of migraine and 9195 had active migraine. Compared with women without migraine and a BMI < 23 kg/m2 , women with a BMI ≥ 35 kg/m2 had adjusted odds ratios (ORs) (95% confidence intervals) of 1.03 (0.95, 1.12) for any history of migraine. Findings were similar for active migraineurs. Women with a BMI of ≥ 35 kg/m2 had increased risk for low and high migraine frequency, with the highest estimate for women who reported daily migraine. Compared with women with the lowest associated risk (migraine frequency < 6 times/year; BMI between 27.0 and 29.9 kg/m2 ), women with a BMI ≥ 35 kg/m2 had an OR of daily migraine of 3.11 (1.12, 8.67). Among the women with active migraine, a BMI ≥ 35 kg/m2 was associated with increased risk of phonophobia and photophobia and decreased risk of a unilateral pain characteristic and migraine aura. Our data confirm previous findings that the association between BMI with migraine is limited to migraine frequency and specific migraine features. 相似文献
89.
In vivo behavior of human radioiodinated antithrombin III: distribution among three physiologic pools 总被引:3,自引:0,他引:3
It has recently been shown that antithrombin III (AT) distributes between plasma, a noncirculating vascular-associated pool and an extravascular pool in rabbit. Study of the in vivo behavior of autologous human 131I-AT demonstrates that in humans AT also distributes among three pools that are analogous to those found in rabbit. From the in vivo kinetic behavior of the 131I-labeled AT, the fractions of total-body AT in the plasma, noncirculating vascular- associated, and extravascular pools were calculated to be 0.393 +/- 0.015, 0.109 +/- 0.016, and 0.496 +/- 0.014, respectively. From three- exponential plasma radioactivity disappearance curves, an average plasma fractional catabolic rate, j3, of 0.576 +/- 0.034 day-1 was obtained for five healthy young men. This is almost identical to the result obtained if plasma 131I-AT disappearance is assumed to fit a two- exponential curve (0.546 +/- 0.038), where the constant C2 from *Ap(t) = C1e-a1t + C2e-a2t is assumed to be equal to 1 - C1. The fraction of the total vascular AT catabolized daily, j3.5, was calculated to be 0.457 +/- 0.034, and the fractional catabolic rate of total-body AT, jT, averaged 0.2271 +/- 0.0176. The results give further support to a model of in vivo behavior in which the vascular AT distributes between plasma and an endothelial receptor. Thus, the latter may serve to mediate activation of AT for its reaction with coagulation proteases and to mediate its entrance into the endothelial cell, where it is either transported to the extravascular fluids or is catabolized. 相似文献
90.
Abstract Protein-chemical and molecular studies were conducted on all osteogenesis imperfecta (OI) type III/IV patients referred to our hospital during the last 15 y. Of a total of 16 OI type III/IV patients studied, 15 patients were heterozygous for a mutation in one of the two genes coding for collagen I, COL1A1 or COL1A2. Cultured fibroblasts from these 15 patients produced both normal and abnormal collagen I molecules, pointing to a dominant-negative effect of the mutation. Nine mutations had not been described previously. Parental mosaicism was demonstrated in three families. In the 16th child the causative mutation was not found. In conclusion, OI type III/IV in most patients of Western European ancestry is caused by dominant mutations in the genes for collagen I, and recurrence of OI is caused in most cases by parental gonadal mosaicism. 相似文献