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991.
992.

Introduction

The incidence of left ventricular (LV) thrombus formation in ST-segment elevation myocardial infarction (STEMI) patients in the current era of primary percutaneous coronary intervention (PCI) is not well established. We performed a meta-analysis to assess the actual incidence and predictors of LV thrombus by cardiovascular magnetic resonance (CMR) in STEMI treated by primary PCI.

Methods

We searched MEDLINE and EMBASE databases up to February 2018. We included all studies published as a full-text article, reporting the incidence of LV thrombus by CMR within 1 month following acute STEMI in patients treated by primary PCI. A binary random-effects model was used to estimate the pooled incidence of LV thrombus. The diagnostic performance of transthoracic echocardiography (TTE) as compared with CMR was pooled to obtain the sensitivity and specificity of TTE with CMR as the gold standard. Embolic and bleeding complications of LV thrombus were also evaluated.

Results

Ten studies were included in the meta-analysis. The incidence of LV thrombus by CMR in all-comer STEMI patients (n?=?2072) was 6.3% with 96% of LV thrombus occurring in those with anterior STEMI (12.2% incidence). When only anterior STEMI with LVEF<?50% were considered (n?=?447), the incidence of LV thrombus was 19.2%. Compared with CMR, the sensitivity of TTE to detect LV thrombus was 29% with a specificity of 98%. The sensitivity of TTE increased to 70% in those with anterior STEMI and reduced LVEF. LV thrombus resolved in 88% of cases by 3 to 6 months. After 1–2 years follow-up, the embolic complication rate was similar at 1.5% (P?=?0.25) but the bleeding complication rate was significantly higher (8.8% versus 0.5%, P?<?0.001) in the LV thrombus group on triple therapy when compared to the no LV thrombus group on dual antiplatelet therapy.

Conclusion

In the primary PCI era, CMR detection of an LV thrombus post-STEMI remains high with incidence of nearly 20% in anterior STEMI with depressed LVEF. Patients with LV thrombus treated by triple therapy had similar embolic complications but higher bleeding complications than those with no LV thrombus treated with dual antiplatelet therapy. A 3 month follow-up CMR scan to guide anticoagulation duration might help mitigate bleeding risk.
  相似文献   
993.
994.
目的 探讨继发性甲状旁腺功能亢进症(secondary hyperparathyroidism,SHPT)患者甲状旁腺组织病理形态改变与甲状旁腺激素水平、透析龄等因素的关系.方法 通过形态学观察比较,研究48例规律透析患者因SHPT切除的甲状旁腺病理学形态特征.结果 甲状旁腺激素水平与增生甲状旁腺的细胞类型无相关性,与患者性别、继发陈旧性出血及钙化程度无相关性(P>0.05),48例规律透析患者SHPT (95.8%,46/48)以甲状旁腺结节状增生为主,甲状旁腺继发性出血(70.8%,34/48)及钙化(62.5%,30/48)在SHPT的规律透析患者中广泛存在,透析龄的延长对钙化的程度及范围影响较大(P<0.05).电镜下可见增生的甲状旁腺细胞内含丰富的线粒体及核蛋白体.结论 长期规律透析患者形成SHPT时甲状旁腺内钙化灶形成及反复的出血是常见的继发性改变,结节状增生是难治性继发性甲状旁腺增生的病理形态基础.电镜下所见提示增生的甲状旁腺细胞呈高活性状态.  相似文献   
995.
Nowadays, chemotherapy is one of the crucial and common therapies in the world. So far, it has been revealed to be highly promising, yet patients suffer from the consequences of severe negative medical dosages. In order to overcome these issues, the enhancement of photothermal chemotherapy with reduced graphene oxide (rGO) as a photothermal agent (PTA) is widely utilised in current medical technologies. This is due to its high near-infrared region (NIR) response, in vitro or in vivo organism biocompatibility, low risk of side effects, and effective positive results. Moreover, rGO not only has the ability to ensure that selective cancer cells have a higher mortality rate but can also improve the growth rate of recovering tissues that are untouched by necrosis and apoptosis. These two pathways are specific diverse modalities of cell death that are distinguished by cell membrane disruption and deoxyribonucleic acid (DNA) disintegration of the membrane via phosphatidylserine exposure in the absence of cell membrane damage. Therefore, this review aimed to demonstrate the recent achievements in the modification of rGO nanoparticles as a PTA as well as present a new approach for performing photochemotherapy in the clinical setting.

rGO of QD-rGO nanocomposite could absorb and convert into heat when harvested under NIR radiation, resulting cell death with reduction of fluorescence.  相似文献   
996.

Objective

To investigate the possible association of the Fcγ receptor IIb (FcγRIIb) Ile/Thr187 transmembrane domain polymorphism, which significantly affects receptor signaling, with susceptibility to systemic lupus erythematosus (SLE) in Taiwanese patients.

Methods

We used matrix‐assisted laser desorption ionization−time‐of‐flight mass spectrometry to genotype 351 Taiwanese SLE patients and 372 age‐ and sex‐matched healthy individuals from the same geographic area. Allele frequencies and genotype distributions were compared between the patients and controls, both as an aggregate and as stratified by sex, autoantibody profile, and clinical parameters. A combined analysis was conducted to assess the FCGR2B Thr187 allele as a common risk factor in different ethnic populations.

Results

The minor Thr187 allele was significantly associated with SLE in Taiwanese subjects (P = 0.017, odds ratio [OR] 1.989 [95% confidence interval (95% CI) 1.119–3.553]). Interestingly, male SLE patients showed enrichment of the Thr/Thr187 genotype (24%; 7 of 29) as compared with female SLE patients (10%; 32 of 322) (P = 0.043, OR 2.884 [95% CI 1.028–7.839]). Additionally, SLE patients with Thr/Thr187 and Ile/Thr187 genotypes were more likely to have pleural effusions (P = 0.038, OR 1.874 [95% CI 1.033–3.411]) and anti‐SSA/Ro antibody production (P = 0.046, OR 2.221 [95% CI 1.013–4.897]). Combined analysis of 4 groups of Asian patients strongly supported the association of the FCGR2B Thr187 allele with the lupus phenotype (P = 0.000159).

Conclusion

The FcγRIIb transmembrane polymorphism is a strong disease susceptibility candidate in epistasis with other genetic effects in Taiwanese and other Asian populations. It may also play a more prominent role in male patients with SLE.
  相似文献   
997.
After intranasal, subcutaneous, or intraperitoneal infection with Dhori virus (DHOV), adult mice developed a fulminant and uniformly fatal illness with many of the clinical and pathologic findings seen in mice infected with H5N1 highly pathogenic avian influenza A virus. Histopathologic findings in lungs of DHOV-infected mice consisted of hemorrhage, inflammation, and thickening of the interstitium and the alveolar septa and alveolar edema. Extra-pulmonary findings included hepatocellular necrosis and steatosis, widespread severe fibrinoid necrosis in lymphoid organs, marked lymphocyte loss and karyorrhexis, and neuronal degeneration in brain. Similar systemic histopathologic findings have been reported in the few fatal human H5N1 cases examined at autopsy. Because of the relationship of DHOV to the influenza viruses, its biosafety level 2 status, and its similar pathology in mice, the DHOV-mouse model may offer a low-cost, relatively safe, and realistic animal model for studies on the pathogenesis and management of H5N1 virus infection.  相似文献   
998.
BACKGROUND: In spite of a substantial body of empirical data, professional disagreement persists regarding whether and how religion and spirituality (hereinafter "R/S" and treated as a single concept) influences health. This study examines the association between physicians' religious characteristics and their observations and interpretations of the influence of R/S on health. METHODS: A cross-sectional survey was mailed to a stratified, random sample of 2000 practicing US physicians from all specialties. Physicians were asked to estimate how often patients mention R/S issues, how much R/S influences health, and in what ways the influence is manifested. RESULTS: The response rate was 63%. Most physicians (56%) believed that R/S had much or very much influence on health, but few (6%) believed that R/S often changed "hard" medical outcomes. Rather, most physicians believed that R/S (1) often helps patients to cope (76%), (2) gives patients a positive state of mind (75%), and (3) provides emotional and practical support via the religious community (55%). Compared with those with low religiosity, physicians with high religiosity are substantially more likely to (1) report that patients often mention R/S issues (36% vs 11%)(P<.001); (2) believe that R/S strongly influences health (82% vs 16%) (P<.001); and (3) interpret the influence of R/S in positive rather than negative ways. CONCLUSION: Patients are likely to encounter quite different opinions about the relationship between their R/S and their health, depending on the religious characteristics of their physicians.  相似文献   
999.
Protein oligomerization and aggregation are key events in age-related neurodegenerative disorders, causing neuronal disturbances including microtubule destabilization, transport failure and loss of synaptic integrity that precede cell death. The abnormal buildup of proteins can overload digestive systems and this, in turn, activates lysosomes in different disease states and stimulates the inducible class of lysosomal protein degradation, macroautophagy. These responses were studied in a hippocampal slice model well known for amyloidogenic species, tau aggregates, and ubiquitinated proteins in response to chloroquine-mediated disruption of degradative processes. Chloroquine was found to cause a pronounced appearance of prelysosomal autophagic vacuoles in pyramidal neurons. The vacuoles and dense bodies were concentrated in the basal pole of neurons and in dystrophic neurites. In hippocampal slice cultures treated with Abeta(142), ultrastructural changes were also induced. Autophagic responses may be an attempt to compensate for protein accumulation, however, they were not sufficient to prevent axonopathy indicated by swellings, transport deficits, and reduced expression of synaptic components. Additional chloroquine effects included activation of cathepsin D and other lysosomal hydrolases. Abeta(142) produced similar lysosomal activation, and the effects of Abeta(142) and chloroquine were not additive, suggesting a common mechanism. Activated levels of cathepsin D were enhanced with the lysosomal modulator Z-Phe-Ala-diazomethylketone (PADK). PADK-mediated lysosomal enhancement corresponded with the restoration of synaptic markers, in association with stabilization of microtubules and transport capability. To show that PADK can modulate the lysosomal system in vivo, IP injections were administered over a 5-day period, resulting in a dose-dependent increase in lysosomal hydrolases. The findings indicate that degradative responses can be modulated to promote synaptic maintenance.  相似文献   
1000.
The aim of this study was to investigate genetic effects on the pathogenesis of chronic obstructive pulmonary disease (COPD). The study was conducted as a prospective case–control study in a medical center in southern Taiwan. The patient group consisted of 145 male patients with smoking-related COPD and a control group of 139 resistant smokers from July 2004 to September 2009. We compared allele and genotype frequencies of three tag single nucleotide polymorphisms (SNP) of the TNF-α gene promoter region at −308, −863, and −1031 in all subjects. We also analyzed the influence of each genetic variant on pulmonary function parameters, body mass index (BMI), serum TNF-α levels, and outcomes among heavy smokers with or without COPD. COPD patients had a significantly lower A allele frequency (9.7 vs. 15.1%, OR = 0.6, p = 0.048, false discovery rate q = 0.144) and a significantly lower A carrier genotype frequency (19.3 vs. 30.2%, OR = 0.52, p = 0.042, q = 0.135) than resistant smokers. The −863 CA genotype was associated with a better FEV1/FVC ratio (79 vs. 71.5%, p = 0.034), and higher BMI (24.9 vs. 23.6 kg/m2, p = 0.048). In addition, COPD patients with the −1031 C carrier genotype had higher serum TNF-α levels (20.9 vs. 16.2 pg/ml, p = 0.01). BMI (hazard ratio = 0.84, 95% CI = 0.74–0.96, p = 0.008) was the only independent predictor for mortality. The TNF-α −863 A allele may confer a degree of resistance to the susceptibility to and muscle wasting of COPD among heavy smokers.  相似文献   
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