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121.

Background

Gross trunnion failure (GTF) is a rare complication in total hip arthroplasty (THA) reported across a range of manufacturers. Specific lots of the Stryker low friction ion treatment (LFIT) anatomic cobalt chromium alloy (CoCr) V40 femoral head were recalled in August 2016. In part, the recall was based out of concerns for disassociation of the femoral head from the stem and GTF.

Methods

We report on 28 patients (30 implants) with either GTF (n = 18) or head-neck taper corrosion (n = 12) of the LFIT CoCr femoral head and the Accolade titanium-molybdenum-zirconium-iron alloy femoral stems. All these cases were associated with adverse local tissue reactions requiring revision of the THA.

Results

In our series, a conservative estimate of the incidence of failure was 4.7% (n = 636 total implanted) at 8.0 ± 1.4 years from the index procedure. Failures were associated with a high-offset 127° femoral stem neck angle and increased neck lengths; 43.3% (13 of 30) of the observed failures included implant sizes outside the voluntary recall (27.8% [5 of 18] of the GTF and 75.0% [8 of 12] of the taper corrosion cases). Serum cobalt and chromium levels were elevated (cobalt: 8.4 ± 7.0 μg/mL; chromium: 3.4 ± 3.3 μ/L; cobalt/chromium ratio: 3.7). The metal artifact reduction sequence magnetic resonance imaging demonstrated large cystic fluid collections typical with adverse local tissue reactions. During revision, a pseudotumor was observed in all cases. Pathology suggested a chronic inflammatory response. Impending GTF could be diagnosed based on aspiration of black synovial fluid and an oblique femoral head as compared with the neck taper on radiographs.

Conclusion

In our series of the recalled LFIT CoCr femoral head, the risk of impending GTF or head-neck taper corrosion should be considered as a potential diagnosis in a painful LFIT femoral head and Accolade titanium-molybdenum-zirconium-iron alloy THA with unknown etiology. Almost half of the failures we observed included sizes outside of the voluntary recall.  相似文献   
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Sick preterm and term newborns are highly vulnerable to neural injury, and thus there has been a major search for new, safe and efficacious neuroprotective interventions in recent decades. Preclinical studies are essential to select candidate drugs for clinical trials in humans. This article focuses on 'negative' preclinical studies, i.e. studies where significant differences cannot be detected. Such findings are critical to inform both clinical and preclinical investigators, but historically they have been difficult to publish. A significant amount of time and resources is lost when negative results or nonpromising therapeutics are replicated in separate laboratories because these negative results were not shared with the research community in an open and accessible format. In this article, we discuss approaches to strengthen conclusions from negative preclinical studies and, conversely, to reduce false-negative preclinical evaluations of potential therapeutic compounds. Without being exhaustive, we address three major issues in conducting and interpreting preclinical experiments, including: (a) the choice of animal models, (b) the experimental design, and (c) issues concerning statistical analyses of the experiments. This general introduction is followed by synopses of negative data obtained from studies of three potential therapeutics for perinatal brain injury: (1) the somatostatin analog octreotide, (2) an AMPA/kainate receptor antagonist, topiramate, and (3) a pyruvate derivative, ethyl pyruvate.  相似文献   
124.
与新生儿缺氧缺血性脑病相关的热点问题   总被引:3,自引:0,他引:3  
朱长连教授受<中国循证儿科杂志>编辑部委托,在"第二届上海国际新生儿医学论坛"会议期间,很高兴邀请到国际新生儿领域的诸位知名专家就"与新生儿缺氧缺血性脑病(HIE)相关的热点问题"进行讨论,希望能对中国新生儿HIE的诊断与治疗有所帮助.  相似文献   
125.
We sought to determine whether seliciclib (CYC202, R‐roscovitine) could increase the antitumor effects of doxorubicin, with no increase in toxicity, in an MCF7 breast cancer xenograft model. The efficacy of seliciclib combined with doxorubicin was compared with single agent doxorubicin or seliciclib administered to MCF7 cells and to nude mice bearing established MCF7 xenografts. Post‐treatment cells and tumors were examined by cell cycle analysis, immunohistochemistry and real‐time PCR. Seliciclib significantly enhanced the antitumor effect of doxorubicin without additional murine toxicity. MIB1 (ki67) immunohistochemistry demonstrated reduced proliferation with treatment. The levels of p21 and p27 increased after treatment with doxorubicin or seliciclib alone or in combination, compared to untreated controls. However, no changes in p53 protein (DO1, CM1), survivin or p53 phosphorylation (SER15) were observed in treated tumors compared with controls. In conclusion, the CDK inhibitor seliciclib (R‐roscovitine) enhances the antitumor effect of doxorubicin in MCF7 tumors without increased toxicity with a mechanism that involves cell cycle arrest rather than apoptosis. © 2008 Wiley‐Liss, Inc.  相似文献   
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The entity 'angioendotheliomatosis proliferans systemisata' was first described 28 years ago as a cutaneous small vessel neoplasm of presumed endothelial origin. Since then, 101 similar cases have been reported under a variety of different names, most with systemic as well as cutaneous lesions, and a lymphoid histogenesis of the tumour cell is now favoured. Review of these cases has shown a characteristic clinical presentation with predominant neurological and dermatological features, although the diagnosis was made at autopsy in 53 per cent of patients. Most therapeutic regimens have proved ineffective with a median survival of 5 months from date of clinical presentation. Aggressive combination chemotherapy can produce complete and lasting remission and a partial response to steroids is sometimes seen. We have examined a case of this condition showing unusual clinical features. Immunohistochemical studies confirm the lymphoid origin of the tumour cells with B cell phenotype. Antigen receptor gene rearrangement studies indicate the presence of the same clonal population of B cells in multiple sites. We suggest that the term 'angioendotheliomatosis proliferans systemisata' should be dropped and support the use of 'angiotropic large cell lymphoma' to describe this unusual condition.  相似文献   
129.
The efficacy of ciprofloxacin, BMY-28142, and ceftazidime was compared in vitro and in experimental left-sided endocarditis due to Pseudomonas aeruginosa in the rat. The dose, dosing interval, and duration of therapy were varied, and the resulting antibiotic levels in serum and vegetations were correlated with bacterial clearance from vegetations. These studies demonstrated that beta-lactams such as BMY exhibited a slow rate of bactericidal action and had no postantibiotic effect against P. aeruginosa in vitro or in vivo. As a consequence, BMY had to be given in multiple doses at relatively short intervals during which concentrations of antibiotics in vegetations were continuously in excess of the MBC for the pathogen. The earlier onset of rapid bactericidal action and the prolonged postantibiotic effect of ciprofloxacin (demonstrated in vivo and in vitro) were, in all likelihood, the factors that allowed the successful use of fewer doses of this antimicrobial agent at relatively longer dosing intervals.  相似文献   
130.
Prevention of infective endocarditis is a priority because this disease is associated with considerable morbidity and mortality both during the acute phase of the illness and subsequently, despite modern medical and surgical treatment. The American Heart Association has published recommendations for prevention by antimicrobial prophylaxis since 1955; the most recent revision of these guidelines appeared in 1997. All practicing physicians should know their content and understand their underlying concepts and assumptions.  相似文献   
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