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1.
Differences in bearing surface conformity and wear mechanisms suggest that the polyethylene (PE) wear debris generated by total knee replacement (TKR) prostheses should be different than that in total hip replacement prostheses (THR). To address this issue, PE wear debris and the cellular response in periprosthetic tissues from 19 failed TKRs was compared to that from 24 failed THRs using polarized light microscopy and a semiquantitative grading system. The foreign-body inflammatory reaction in the THR case was characterized by plump macrophages with a diffuse cytoplasmic birefringence when examined under polarized light, indicating the presence of multiple submicron particles of PE. The majority of PE particles were less than 1 mum in size and only a small fraction of the total were greater than 10 mum. The foreign-body inflammatory reaction in the TKR cases was characterized by giant cells with fewer macrophages. In the TKR specimens, the size range of PE particles was broader than in the hips. PE particles between 2 and 20 mum were frequent in TKR specimens; particles less than 1 mum in length were less common than in the THR specimens. Diffuse cytoplasmic birefringence was not a characteristic of the TKR cases. These histologic differences were so consistently distinct that the source of the specimen (i.e., from a THR or TKR) could be blindly determined by light microscopy.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
Preeclampsia (PE), which is defined as new onset hypertension after 20 weeks of pregnancy accompanied by proteinuria, is characterized by inadequate placentation, oxidative stress, inflammation and widespread endothelial dysfunction. A link between PE and long-term risk of cardiovascular disease (CVD) was suggested by retrospective studies, which found that PE was associated with a 2–3-fold risk of CVD later in life, with a 5–7-fold risk in the case of severe and/or early-onset PE. Recently, meta-analyses and prospective studies have confirmed the association between PE and the emergence of an unfavorable CVD risk profile, in particular a 3–5-fold increased prevalence of the metabolic syndrome only 8 years after the index pregnancy. PE and CVD share many risk factors, including obesity, hypertension, dyslipidemia, hypercoagulability, insulin resistance and both entities are characterized by endothelial dysfunction. PE and CVD are complex traits sharing common risk factors and pathophysiological processes, but the genetic link between both remains to be elucidated. However, recent evidence suggests that genetic determinants associated with the metabolic syndrome, inflammation and subsequent endothelial dysfunction are involved. As the evidence now supports that PE represents a risk factor for the emergence of the metabolic syndrome and CVD later in life, the importance of long-term follow-up assessment of CVD risk beginning early in women with a history of PE must be considered and translated into new preventive measures.  相似文献   

3.
Stiff-man syndrome (STS) is a rare neurological disorder characterized by involuntary axial and proximal limb rigidity and continuous motor unit activity on electromyography (EMG). Autoantibodies to glutamic acid decarboxylase (GAD) present in 60% of the patients are implicated. We report on the use of plasma exchange (PE) in 2 patients with STS whose serum and cerebrospinal fluid were negative for GAD autoantibodies. One patient showed minimal clinical improvement following PE while the second reported subjective improvement, but not any different from that with medications. Based on the results of PE in our patients, it seems that those who are autoantibody negative are less likely to respond. Whether a more aggressive approach to PE will be beneficial remains speculative.  相似文献   

4.
This case study presents the diagnosis and treatment of a child with pectus excavatum (PE), a common congenital abnormality of the anterior chest wall characterized by depression of the lower sternum. This depression ranges in severity from a minor dent to a deep, concave hollow capable of displacing the heart and intrathoracic structures. PE could present as a mild, asymptomatic condition, primarily with cosmetic implications. PE may progress to become a severe pathology that induces both serious physical symptoms and psychosocial problems. Nurse practitioners must implement adequate assessment and care strategies for PE patients to achieve optimal health outcomes.  相似文献   

5.
《Transfusion science》1989,10(1):63-68
Refsum's disease is characterized by the accumulation of phytanic acid (PA). Some clinical features are directly related to serum PA and may therefore improve with plasma exchange (PE). We present a patient with severe polyneuropathy and PA of 1809 mg/L, exacerbated by weight loss of 15 kg. Clinical improvement occurred only when PA fell to 500 mg/L after intensive PE and a high calorie liquid diet. This accords with published reports of severely ill patients which indicate that PE is only effective when combined with dietary control and arrest of weight loss. PE is of questionable value in less severely ill patients with PA < 500 mg/L.  相似文献   

6.
Acute pulmonary embolism (PE) is a common, multidisciplinary disease with substantial associated morbidity, mortality and healthcare expense. In this article we present a succinct review of diagnostic tools, risk stratification and medical therapies for cardiovascular care of patients with acute PE. While pulmonary angiography remains the 'gold standard' for diagnosis, a host of diagnostic modalities, interpreted in the setting of clinical probability, are available for patient assessment, including ECG, chest radiography, D-dimer, lower-extremity venous ultrasound, ventilation-perfusion scans, computed tomography and magnetic resonance angiography, and echocardiography, each with associated value. Diagnostic algorithms incorporate multiple tools in order to obtain a more comprehensive evaluation. Therapeutic anticoagulation remains the mainstay of therapy in PE. In massive PE, utilization of thrombolysis is reasonable in the absence of contraindications. Submassive PE, characterized by right ventricular dysfunction as assessed by echocardiography and ECG, is associated with higher mortality. Use of thrombolysis in submassive PE remains controversial. Catheter-directed therapies are emerging as an added approach to acute PE and have the potential to improve outcomes in PE. Use of inferior vena cava filters should be pursued in a select patient population as they serve to reduce recurrent acute PE; however, they are associated with more frequent deep venous thrombosis and provide no mortality benefit. In risk-stratified hemodynamically stable patients, an outpatient management strategy inclusive of therapeutic anticoagulation and careful clinical follow-up may be appropriate.  相似文献   

7.
血栓性血小板减少性紫癜12例临床分析   总被引:1,自引:0,他引:1  
目的探讨血栓性血小板减少性紫癜的病因、临床特点和治疗效果。方法对我院1993.-2005.6收治的血栓性血小板减少性紫癜(TTP)患者12例进行回顾性分析。结果本组12例患者中,原发性TTP5例,继发性TTP7例;7例继发性TTP中,感染所致2例,自身免疫性疾病伴感染1例,术后1例,宫内死胎1例,肝移植及骨髓移植术后各1例。原发性TTP中1例起病缓、病程达半年呈慢性型,其余4例及继发性均以急性暴发型起病。临床表现为微血管病性溶血性贫血(12/12)、血小板减少(12/12)、神经精神障碍(12/12)、肾脏损害(11/12)、发热(11/12),全部患者均有血清乳酸脱氢酶(LDH)明显升高。7例继发性TTP中4例血浆置换(PE)和病因治疗为主,均治愈,3例未行PE,均死亡;5例原发性TTP中2例行PE,1例治愈,1例死亡,3例未行PE,均死亡。结论本组12例TTP中以继发性TTP多见,多为急性暴发型起病;突出临床表现为微血管病性溶血性贫血、血小板减少、神经精神障碍、肾脏损害、发热,LDH明显升高;死亡率仍高。治疗上应强调PE的重要性;继发性TTP,若病因能有效控制,预后较原发者好。  相似文献   

8.
This study characterized the individual phospholipids within total serum and HDL in the renal patient on long-term maintenance hemodialysis relative to matched controls. The fatty acid composition of these individual phospholipids was also determined by using TLC and gas-liquid chromatography in combination. In agreement with previous findings, our patient group had HDL-cholesterol levels 36% below and total phospholipid levels 30% lower than matched controls. Total serum PE but not HDL-PE was significantly elevated (by 30%) in the serum of the patient group due to a rise in diacyl PE. Significantly reduced HDL-SPH levels (by 41%) and a 31% decrease in HDL-PC levels were noted in the patient group. Considerable differences in the individual fatty acids (as weight percent) of the patient vs. control groups were observed. The percent of 16:0 (palmitate) and 18:0 (stearate) was significantly elevated in the PE of the patient group whereas 18:1 (octadecenoate) was generally elevated in all phospholipids. The weight percent of 18:2 (linoleate) was moderately higher in the PE and Pl of the patient group. Absolute levels of selected fatty acids in PC were generally depressed in the patient HDL relative to control, although significantly so only in the case of 16:0 and 20:4 (arachidonate). In keeping with the total PE levels in whole serum, all fatty acids were elevated in the patient group relative to controls. These results indicate that alterations in certain individual phospholipids and their fatty acids exist in renal patients on dialysis compared to matched controls.  相似文献   

9.
Thrombotic thrombocytopenic purpura (TTP) after bone marrow transplantation (BMT) is an uncommon complication presumably associated with extensive endothelial cell damage due to Cyclosporine, total body irradiation, or other drugs. While the majority of patients with primary TTP, which is considered to be an autoimmune process, respond to plasma exchange, TTP after BMT has a very poor prognosis. A total of 7 patients out of 307 patients who underwent BMT were diagnosed with TTP during 1989-1999. The diagnosis of TTP was made based on thrombocytopenia and microhemangiopathic hemolytic anemia characterized by an elevated LDH and the presence of schistocytes on the peripheral blood smear. Five patients were treated with plasma exchange (PE) using fresh frozen plasma and/or cryoprecipitate poor plasma as replacement fluid. One patient was treated using a protein A column. One patient did not receive plasma exchange because the 125 patient was clinically stable and was discharged. It was hard to assess the efficacy of PE due to the multiplicity of the patients' clinical condition and laboratory data. At least 4 patients did not respond to PE and 2 patients were not able to be evaluated due to multi organ failure. However, all patients died. It is not clear at this moment if PE for patients with TTP after BMT is truly beneficial.  相似文献   

10.
BACKGROUNDCerebral hemorrhage secondary to cerebral embolism after mechanical thrombectomy is characterized by high morbidity, disability and mortality. If the patient also has severe pulmonary embolism (PE) at the same time, the treatment becomes more complex. This report describes the treatment strategy for a patient with PE and cerebral hemorrhage secondary to cerebral embolism after mechanical thrombectomy. CASE SUMMARYA 70-year-old woman presented to our emergency department with right-sided hemiplegia and mixed aphasia of 2.5 h duration. She was diagnosed with left cerebral embolism, left internal carotid artery occlusion, PE and left calf intramuscular vein thrombosis. Following mechanical thrombectomy, brain magnetic resonance imaging showed cerebral infarction with basal ganglia hemorrhage. We observed changes in cerebral hemorrhage on serial monitoring of brain computed tomography and adjusted the dose of anticoagulant drugs. After 3 wk of treatment, the patient’s neurological and respiratory symptoms significantly improved, and a favorable prognosis was obtained.CONCLUSIONAnticoagulation could be a potential option for PE accompanied by hemorrhagic transformation of an ischemic infarct.  相似文献   

11.
BackgroundPreeclampsia (PE) is a pregnancy‐related illness characterized by high blood pressure (BP) and proteinuria after the 20th gestational week (GW). Platelet (PLT) parameter changes are the common hematological abnormalities observed in PE patients. The main aim of this study was to assess the role of PLT parameters for PE diagnosis among pregnant women.MethodsA comparative cross‐sectional study was conducted at the University of Gondar Specialized Hospital. A total of 126 pregnant women (63 normotensive [NT] and 63 PE) were recruited using a convenient sampling method. Three milliliter blood was collected from each participant, and PLT parameters were determined using Sysmex XS‐500i analyzer. An independent t‐test supplemented with receiver‐operating characteristics (ROC) were used for comparisons and diagnostic value of PLT parameters between the study groups.ResultsPlatelet count (PC) was significantly lower in the PE group compared to that in the NT group, whereas mean platelet volume (MPV), platelet large cell ratio (P‐LCR), and platelet distribution width (PDW) were significantly higher in PE. MPV had the largest area under the curve (AUC) [0.91: 95% CI; 0.85–0.96] followed by PC [0.79: 95% CI; 0.72–0.87]. MPV can differentiate PE patients from NT pregnant women at cut‐off value ≥12.10 fl (84.1% sensitivity and 87.3% specificity) while PC can indicate PE at a cut‐off value ≤176.5 × 109/L (65.1% sensitivity and 87.3% specificity).ConclusionA decreased PC and an increased MPV, P‐LCR, and PDW can be used as a simple, cost‐effective, quick, and reliable method of PE screening. Of them, MPV is the best indicator of PE.  相似文献   

12.
Objectives: We characterized patients admitted via ED with a principal hospital discharge diagnosis of pulmonary embolism (PE) and compared mortality of those diagnosed in the ED with those diagnosed after admission. Methods: Patients with a hospital discharge diagnosis ICD 10 I26 presenting to the ED in Perth, Western Australia between 1 July 2000 and 30 December 2006 had records from the Emergency Department Information System linked to the Western Australian Hospital Morbidity Data System and the death registry. Results: Of 2250 patients (mean age 60.4), 1227 (54.5%) were female. Of 1931 patients with an ED diagnosis recorded, 1207 (62.5%) were diagnosed with PE in ED. Of these, 383 (17.0%) had presented to an ED within 28 days previously, 142 (37.1%) with either chest pain or breathing problems, with 207 (54.0%) admitted but not receiving a principal hospital discharge diagnosis of PE. There were 127 (5.6%) in‐hospital deaths. Controlling for age and comorbidity with logistic regression, patients diagnosed with PE in ED were less likely to die in hospital, within 7 and 30 days of ED arrival, than those diagnosed after admission (adjusted OR 0.31, 95% CI 0.20–0.47; adjusted OR 0.32, 95% CI 0.19–0.53; adjusted OR 0.30, 95% CI 0.20–0.44; respectively). Conclusion: Making the diagnosis of PE in ED was associated with a substantial survival advantage that persisted after hospital discharge.  相似文献   

13.
Vascular involvement is presently considered a "common pathway" in a number of diseases that is mediated by circulating immune complexes (CIC). CIC are found in the circulation when the disease is active and in single patients their level may parallel disease activity. Lepromatous leprosis is characterized by the presence of CIC and deposits of immunoglobulins and complement in vascular lesions of the different organs and an Arthus-like mechanism is considered as the basis for the clinical picture. The same mechanism is considered to play an essential pathophysiologic role in Lucio's phenomenon, which is characterized by lymphohistiocytic vascular infiltrates with or without thrombosis and secondary cutaneous infarction. Lepromatous vascular involvement is mediated by CIC whose antigen composition is known, the same as it is with HCV mediated cryoglobulinemia, HBV positive panarteritis nodosa, rheumatoid vasculitis, or Wagner's granulomatosis, which are usually treated by PE [1-3]. PE has been employed for lepromatous vasculitis since 1979 [4] and other cases have been successfully treated afterwards [5,6]. We report on another patient successfully treated by plasma exchange.  相似文献   

14.
目的探讨实时三平面超声心动图(RT-3PE)测量心室容积与心肌重量的可行性与准确性.方法应用RT-3PE采集15个双层橡胶水囊模型的超声图像,沿囊壁勾画并计算内、外囊的容积和囊间液体重量.同时在二维(2DE)超声心动图上采用Simpson's双平面法测定并计算内、外囊的容积和囊间液体重量.上述测值分别与实际注水量对照.结果RT-3PE可实时、直观、真实地显示心室模型的形态.2DE及RT-3PE上内囊容积及囊间液体重量测值与实际值比较均无显著差异(P>0.05),且相关性良好(r为0.919~0.984).R-3PE测量的百分误差与系统偏倚均较2DE小.结论RT-3PE可准确定量测量心室容积和心肌重量,为临床简便、快速地评价心室功能提供了一种新的方法.  相似文献   

15.
Heparin-induced thrombocytopenia (HIT), which is characterized by thrombocytopenia and potentially serious thromboses, may develop in patients exposed to heparin anticoagulation. HIT is caused by antibodies to the heparin/platelet factor 4 (PF4) complex. Management of HIT involves discontinuation of heparin and anticoagulation with a nonheparin alternative such as a direct thrombin inhibitor (DTI). This poses a challenge in the management of patients who need to undergo cardiopulmonary bypass surgery (CPB), because CPB requires anticoagulation with heparin and standardized protocols for use of DTIs are not widely available. We report two patients with HIT who underwent successful CPB with heparin anticoagulation following plasma exchange (PE) to reduce heparin/PF4 antibody titers. Case 1 is a 46-year-old male with cardiac amyloidosis who needed urgent placement of a left ventricular assist device. Case 2 is a 34-year-old woman with acute myocarditis who needed placement of a biventricular assist device. Both patients had positive enzyme-linked immunosorbent assay assays for heparin/PF4 antibodies and clinical evidence of HIT before PE. Following PE and subsequent CPB, neither patient had clinical or laboratory evidence of HIT. The literature regarding the use of PE for the treatment of complications of HIT and as prophylaxis before CPB is reviewed.  相似文献   

16.
Premature ejaculation (PE) is the most common form of male sexual dysfunction, with an estimated worldwide prevalence of 20–30%.1 Although PE is not life threatening, it has significant impact on quality of life. The fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR)defines PE as “persistent or recurrent ejaculation with minimal sexual stimulation before, on, or shortly after penetration and before the person wishes it” that “causes marked distress or interpersonal difficulty” and “is not due exclusively to the direct effects of a substance.”2 The International Society for Sexual Medicine, which recently modified the definition to include the threshold ejaculatory latency time, defines PEas “male sexual dysfunction characterized by ejaculation which always or nearly always occurs prior to or within 1 min of vaginal penetration; the inability to delay ejaculation on all or nearly all vaginal penetrations; and negative personal consequences such as distress, bother, frustration, and/or the avoidance of sexual intimacy.”3 The lack of ejaculatory control is consistent among all clinical definitions of PE and is a highly sensitive predictor of the condition.  相似文献   

17.
PE (pre-eclampsia), a pregnancy-specific disorder, is characterized by increased trophoblast cell death and deficient trophoblast invasion and reduced trophoblast-mediated remodelling of spiral arteries. The present study was performed to determine the function of miR-29b (microRNA-29b) in trophoblast cells and its underlying role in the pathogenesis of PE. The prediction of miR-29b target genes was performed using computer-based programs, including Targetscan, Pictar and miRBase. The function of these target genes was analysed further by gene ontology (GO). The effects of miR-29b on apoptosis, and invasion and angiogenesis of trophoblast cell lines (HTR-8/SVneo, BeWo and JAR) were examined by flow cytometry and Matrigel assay respectively. We found that miR-29b induced apoptosis and inhibited invasion and angiogenesis of trophoblast cells. Further studies confirmed that miR-29b regulated the expression of MCL1 (myeloid cell leukaemia sequence 1), MMP2 (encoding matrix metallproteinase 2), VEGFA (vascular endothelial growth factor A) and ITGB1 (integrin β1) genes by directly binding to their 3'-UTRs (untranslated regions). Moreover, we identified that there was an inverse correlation between miR-29b and its target genes in subjects with PE. Taken together, these findings support a novel role for miR-29b in invasion, apoptosis and angiogenesis of trophoblast cells, and miR-29b may become a new potential therapeutic target for PE.  相似文献   

18.
BACKGROUND: The frequency of the thrombophilic genetic variants factor V Leiden (FVL) G1691A, prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T in acutely symptomatic ambulatory patients with idiopathic pulmonary embolism (PE) has not been measured. METHODS: This prospective case-control study included patients presenting to urban emergency departments (EDs) with chest pain or shortness of breath. Cases were classified as idiopathic PE (49 patients with PE, but without overt risk factors for thrombosis). Control groups included (a) patients with nonidiopathic PE (152 patients with PE and risk factors); (b) patients in whom PE was excluded (91 patients who had PE ruled out with a structured protocol, including follow-up); and (c) patients in whom PE was not suspected (193 patients without a workup for PE, who were free of PE on follow-up). Blood DNA extracts were analyzed by PCR and restriction fragment length polymorphism analysis for the FVL, prothrombin, and MTHFR sequence variations. RESULTS: Either the FVL or prothrombin variant was found in 10% (95% confidence interval, 3%-22%) of patients with idiopathic PE compared with 13% (8%-20%) of nonidiopathic PE, 2% (5%-14%) of PE excluded, and 9% (5%-14%) of PE not suspected patients. Patients with idiopathic PE tended to have a higher frequency of homozygous MTHFR sequence variants, but mean (SD) plasma homocysteine concentrations were not increased [15.6 (5.4) micromol/L vs 12.8 (4.6) micromol/L for homozygous, and wild-type, respectively; P = 0.40]. CONCLUSIONS: The frequency of either the FVL or prothrombin sequence variant was not increased in idiopathic PE patients compared with nonidiopathic PE patients or patients who had PE excluded. These data suggest that genotyping to detect idiopathic PE would have limited clinical utility in the urban ED setting.  相似文献   

19.
目的:讨论肺栓塞的CT征象及螺旋CT三维重建对肺栓塞(PE)的诊断价值。方法:对7例肺栓塞病人进行螺旋CT血管造影检查确定肺栓塞的形态,部位和数目。结果:7例患共累及55处肺动脉极其分支,其CT表现部分充盈缺损,其在垂直面上表现为圆形充盈缺损,在水平面上呈轨道状充盈缺损;完全性堵塞或中断;环状狭窄。结论:螺旋CT血管造影对肺栓塞诊断有极高价值。  相似文献   

20.
The disordered production of extracellular inorganic pyrophosphate (PPi) by cartilage contributes to calcium pyrophosphate dihydrate crystal formation and associated diseases. We have previously shown that a factor(s) derived from human platelets markedly stimulates the accumulation of PPi in the media of porcine articular cartilage in organ culture. This is the first known physiologic modifier of PPi production by cartilage. We report herein that platelet derived growth factor (PDGF) is not the platelet factor responsible for PPi stimulation and that the active factor is not mitogenic for chondrocytes. PDGF added to the media of articular cartilage explants in the presence of 0.5% (platelet-poor) plasma (PPP) produces 3.92 +/- 1.6 mumol/L PPi compared with 2.85 +/- 0.7 mumol/L PPi in cartilage exposed to PPP alone. The platelet extract (PE) and PDGF are mitogenic for adult articular chondrocytes in high-density monolayer cultures. Anti-PDGF antibodies block the mitogenic effects of PDGF and PE. The uptake of thymidine labeled with tritium is 157% of control in cells exposed to PE, PPP, and polyclonal goat immunoglobulin G (IgG); 114% of control in cells exposed to PE, PPP, and anti-PDGF antibody; 148% of control in cells treated with PDGF, PPP, and goat IgG; and 98% of control in cells treated with PDGF, PPP, and anti-PDGF antibody. However, anti-PDGF antibody has no effect on PPi accumulation. PPi levels are 17.22 +/- 1.6 mumol/L in media from cartilage treated with PPP, goat IgG, and PE and 17.62 +/- 2.2 mumol/L in cartilage exposed to PE, PPP, and anti-PDGF antibody. We have further characterized the platelet factor responsible for the stimulation of PPi by cartilage. It is not mitogenic for chondrocytes, and it is not PDGF.  相似文献   

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