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Vasileios Zampelis Ola Belfrage Magnus Tägil Martin Sundberg Gunnar Flivik 《Acta orthopaedica》2018,89(1):17-22
Background and purpose — Impaction bone grafting (IBG) in revision hip surgery is an established method in restoring bone stock deficiencies. We hypothesized that local treatment of the morsellized allograft with a bisphosphonate in cemented revision would, in addition to increased bone density, also reduce the early migration of the cup as measured by radiostereometry (RSA).Patients and methods — 20 patients with aseptic cup loosening underwent revision using the IBG technique. The patients were randomized to either clodronate (10 patients) or saline (10 patients, control group) as local adjunct to the morsellized bone. The outcome was evaluated by dual-energy X-ray absorptiometry (DXA) during the first year regarding periacetabular bone density and with radiostereometric analysis (RSA) for the first 2 years regarding cup migration.Results — 2 patients were lost to follow-up: 9 patients remained in the clodronate and 9 in the control group. Less proximal migration was found in the clodronate group compared with the controls, measured both over time (mixed-models analysis, p = 0.02) as well as at the specified time points up to 2 years (0.22?mm and 0.59?mm respectively, p = 0.02). Both groups seemed to have stabilized at 1 year. We found similar bone mineral density measured by DXA, and similar RSA migration in the other directions. No cups were re-revised.Interpretation — Local treatment of the allograft bone with clodronate reduced early proximal migration of the revised cup but without any measurable difference in periacetabular bone density. 相似文献
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The relative contribution of transcytosis vs. large pore transport to the passage of macromolecules across microvascular endothelia has been a controversial issue for nearly half a century. To separate transcytosis from 'porous' transport, the transcytosis inhibitors N-ethylmaleimide (NEM) and filipin have been tested in in situ or ex vivo perfused organs with highly conflicting results. In continually weighed isolated perfused organs, where measurements of pre- and post-capillary resistances, capillary pressure and capillary filtration coefficients can be repeatedly performed, high doses of NEM and filipin increased the bulk transport of macromolecules from blood to tissue, despite producing vasoconstriction. By contrast, in in situ perfused organs, marked reductions in the tissue uptake of albumin tracer have been observed after NEM and filipin. When tissue cooling has been employed as a means of inhibiting (active) transcytosis, results have invariably shown a low cooling sensitivity of albumin transport, compatible with passive transendothelial passage of albumin. This observation is further strengthened by the commonly observed dependence of albumin transport upon the capillary pressure and the rate of transcapillary convection. For low-density lipoprotein (LDL), a cooling-sensitive, non-selective transport component has been discovered, which may be represented by filtration through paracellular gaps, lateral diffusion through transendothelial channels formed by fused vesicles, or by transcytosis. From a physiological standpoint there is little evidence supporting active transendothelial transport of most plasma macromolecules. This seems to be supported by studies on caveolin-1-deficient mice lacking plasmalemmal vesicles (caveolae), in which there are no obvious abnormalities in the transendothelial transport of albumin, immunoglobulins or lipoproteins. Nevertheless, specific transport in peripheral capillaries of several hormones and other specific substances, similar to that existing across the blood-brain barrier, still remains as a possibility. 相似文献
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Autoantibodies against 21-hydroxylase and side-chain cleavage enzyme in autoimmune Addison's disease are mainly immunoglobulin G1 总被引:1,自引:0,他引:1
Bøe AS Bredholt G Knappskog PM Hjelmervik TO Mellgren G Winqvist O Kämpe O Husebye ES 《European journal of endocrinology / European Federation of Endocrine Societies》2004,150(1):49-56
OBJECTIVE: Immunoglobulin G (IgG) antibodies to the steroidogenic enzymes 21-hydroxylase (21OH) and side-chain cleavage enzyme (SCC) are important diagnostic markers for autoimmune Addison's disease and autoimmune polyendocrine syndromes (APS) types I and II. The characterization of autoantibody (IgG) subclasses may reveal information on how tIssue destruction takes place; therefore, IgG subtypes of anti-21OH and anti-SCC antibodies from sera of patients with Addison's disease, APS I and APS II were determined using recombinant 21OH and SCC. METHODS: SCC(51-521) and his-SCC(51-521) were expressed by pET-scc in the Escherichia coli strain BL21 Star (DE3) and inclusion bodies were purified. Full-length, human 21OH fused to an N-terminal 6x histidine affinity tag was expressed in insect cells by using the baculovirus expression system bac-to-bac. Western blots were used to investigate the IgG subtype(s) of the autoantibodies against 21OH and SCC in patients and healthy blood donors. RESULTS: All anti-SCC positive sera (n=10) contained autoantibodies of the IgG1 subclass, while four out of ten also contained IgG3. All anti-21OH positive sera (n=16) had autoantibodies exclusively against IgG1. Sera from 20 healthy subjects did not show any reactivity against 21OH or SCC. CONCLUSIONS: The finding of a predominating IgG1 response against 21OH and SCC may suggest that T helper (Th) cells of the Th1 subclass are involved in destruction of the adrenal cortex in patients with autoimmune Addison's disease. 相似文献
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Hassoba H Leheta O Sayed A Fahmy H Fathy A Abbas F Attia F Serwah A 《The Egyptian journal of immunology / Egyptian Association of Immunologists》2003,10(1):1-8
Hepatitis C virus (HCV) is the leading cause of chronic liver disease worldwide with a prevalence of approximately 14% in Egypt. IL-10 is a cytokine produced by Th2 cells. It down-regulates the proinflammatory response and modulates hepatic fibrogenesis. IL-12 is produced by antigen presenting cells. It promotes Th1 cell response and has many antiviral properties. Data concerning the Th-1/Th-2 balance in chronic hepatitis C (CH-C) are rather conflicting. Using ELISA, we assessed serum IL-10 and IL-12p40 levels in 66 Egyptian patients with HCV-related liver illness (CH-C, cirrhosis, and HCC), and their relationship to disease activity. Our results showed that spontaneous IL-10 was undetectable in patients with CH-C, HCC or controls. Only 5/22 (23%) of patients with cirrhosis showed detectable levels of IL-10. IL-12p40 was elevated in the patient groups compared to controls (p= 0.01, p= 0.01, p= 0.05 in CH-C, cirrhosis and HCC, respectively). The presence of IL-12p40 was associated with HCV level of viremia and serum AST. Serum ALT level was significantly associated with the level of IL-12p40. IL-12p40 was unrelated to liver histology or fibrosis. We concluded that in the Egyptian patients an augmentation of IL-12p40 and a suppression of IL-10 are both found. Whether this pattern is related to HCV genotype 4, or to the presence of schistosomiasis would need to be further investigated. 相似文献
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The more complex influences of social problem-solving abilities and rumination—specifically brooding and reflection—on suicide intent is not well understood. We hypothesized that social problem solving would moderate the association between reflection and suicide intent, and mediate the influence of brooding on suicide intent. A convenience sample (N = 186) of individuals hospitalized for recent suicide attempt was interviewed, assessing suicide intent, social problem solving, brooding, reflection and depression. Brooding and reflection were positively associated with suicide intent. The mediating, but not the moderating, hypothesis was supported. Brooding was not significant (β = 0.15, t = 1.92, p = 0.06) with social problem solving controlled. Interventions to disengage rumination and improve social problem-solving skills are underscored. 相似文献
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