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61.
Psammoma bodies (PBs) in breast lesions are rare and little is known about the role of these structures in breast pathology. This study has looked in to the diagnostic significance of PBs in fine needle aspiration (FNAC) of breast lesions. Over a 5‐year period, FNACs of the breast were done in 4,563 subjects, of which 1,678 were diagnosed to be malignant. On review of all breast aspirates including non‐neoplastic lesions, 30 cases showed PBs to be associated with breast carcinoma (BC). Cytological features were correlated with clinical, radiological, histological, and immunohistochemical findings. All 30 aspirates and their corresponding histological sections showed varying number of PBs and nonpsammomatous bodies (NPBs). For comparison, 31 cases of age‐matched BC without PBs and NPBs in both aspirates and sections were studied. Statistical analysis using Chi‐square test was done to compare BC with and without PBs. BC with PBs was characterized by papillary pattern of malignant cells, mucin in the background, infiltration by macrophages, cellular degeneration, overexpression of estrogen receptor (ER), and progesterone receptor (PR) and moderate positivity (2+) for Her2/neu. Calcium deposition has long been implicated in the pathogenesis of many degenerative diseases; hence the formation of PBs may be relevant in breast oncology. The presence of PBs in FNAC of clinically suspected breast lesions which are cytologically negative for malignancy warrants further histological confirmation. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc.  相似文献   
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Atrial fibrillation (AF) is a very common tachyarrhythmia and is becoming increasingly prevalent, while dementia is a neurological condition manifested as loss of memory and cognitive ability. Both these conditions share several common risk factors. It is becoming increasingly evident that AF increases the risk of dementia. There are several pathophysiological mechanisms by which AF can cause dementia. AF increases the stroke risk and strokes are strongly associated with dementia. Besides stroke, altered cerebral blood flow in AF and cerebral microbleeds from anticoagulation may enhance the risk of dementia. Maintaining sinus rhythm may therefore decrease this risk. Catheter ablation is emerging as an effective alternative to maintain patients in sinus rhythm. This procedure has also shown promise in decreasing the risk of all types of dementia. Besides maintaining sinus rhythm and oral anticoagulation, aggressive risk factor modification may reduce the likelihood or delay the onset of dementia.  相似文献   
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65.

Background

The prevalence and predictors of atrial tachyarrhythmias (ATa) in patients with pulmonary hypertension (PH) is less well understood.

Methods

We performed a retrospective study including 311 patients with PH, confirmed by right heart catheterization in our center between 2007 and 2011. Baseline characteristics, clinical, echocardiographic, and hemodynamic data were collected and compared between patients with and without ATa.

Results

The mean age was 61?±?13 years with 64 % females. The mean pulmonary artery pressure (mPAP) was 46?±?20 mmHg, mean left ventricular ejection fraction (LVEF) was 55?±?13 %, and mean pulmonary capillary wedge pressure (PCWP) was 19?±?9 mmHg. Of the 311 patients with PH, 121 (39 %) patients had ATa. Patients with ATa were older (p?p?=?0.03), diabetes (p?=?0.015), coronary artery disease (p?p?p?=?0.001), impaired LVEF (p?=?0.02), and left atrial enlargement (p?p?=?0.022). In multivariate analysis using Cox-proportional hazard model, the independent predictors of mortality were age (HR 1.05; p?=?0.003), coronary artery disease (HR 2.34; p?=?0.047), LVEF (HR 0.793; p?=?0.023), and mPAP (HR 1.023; p?=?0.003).

Conclusion

ATa are common in patients with PH. Left heart disease, left atrial enlargement, and elevated PCWP but not right atrial enlargement or mPAP predict the occurrence of ATa in patients with PH.  相似文献   
66.

Introduction

While early postoperative atrial fibrillation (post op AF) following valve and coronary artery bypass surgery is a known common cause of increased morbidity and mortality, the late recurrence of AF long term in this group of patients has not been well studied.

Objective

The objective of this study was to assess the late recurrence and predictors of AF in patients undergoing open heart surgery.

Methods

From a prospective cardiovascular surgery registry, 519 patients with no prior history of AF who underwent open heart surgery for cardiac bypass/valvular surgeries between May 2000 and April 2004 were followed until May 2009. A Cox proportional hazards model was used to assess the impact of early post op AF on the long-term AF after adjusting for significant covariates

Results

Of these patients, 25.6 % (133) had early (0–3 months) post op AF (group A). The remainder of patients were considered as controls (group B, n?=?386). Late occurrence of AF (3–84 months) was 5.3 % (n?=?28) after a mean follow up duration of 5?±?1.9 years. The late occurrence of AF in group A (recurrent AF) was significantly higher than in group B (11 vs 3 % n?=?15 vs 13, p?=?0.0002). Early postoperative AF was a significant predictor of late recurrence of AF in multivariate analysis (hazard ratio (HR) 3.9, CI 1.8–8.4, p?=?0.0003). Group A also had higher mortality compared to group B (21 vs 13 %, n?=?28 vs n?=?51, p?=?0.003) with early postoperative AF showing a trend towards higher mortality on multivariate analysis (HR 1.7, p?=?0.06).

Conclusions

Late recurrence of AF is higher than was previously thought to be in patients experiencing early post operative AF with a trend towards higher long-term mortality. Post op AF should not be dismissed as a benign entity and these patients should be followed closely.  相似文献   
67.
Brain dopamine influences immune functions and the role of immune functions in tumor growth is well established. Therefore, a study has been carried out to evaluate the correlation, if any, between brain dopamine and tumor growth. MPTP selectively destroys dopaminergic neurons in the brain. In the present study, Ehrlich carcinoma growth was evaluated in MPTP-treated mice. Results showed a correlation between depletion of striatal dopamine and enhanced tumor growth. Since in the present study striatal dopamine depletion in mice was associated with significantly decreased immune responses, the suggested correlation between brain dopamine and tumor growth was possibly mediated by the immune system.  相似文献   
68.
A parapharyngeal metastasis from primary thyroid carcinoma is rare and a search of relevant publications disclosed only seven previous reported cases. We describe a 46-year-old man who presented with a left parapharyngeal mass that was subsequently diagnosed by peroral fine-needle aspiration as a metastasis originating from a papillary carcinoma of the thyroid gland. Metastatic thyroid cancer should be considered in the differential diagnosis of a parapharyngeal mass. Fine-needle aspiration cytology is a simple, speedy, and cost-effective method of diagnosis of parapharyngeal masses.  相似文献   
69.
Several lines of evidence suggest that human uterine endometrial cells can bind human chorionic gonadotropin (hCG) which, in turn, influences the physiology of implantation stage endometrium. Vascular endothelial growth factor (VEGF) appears to be a candidate mediator in this process. However, our knowledge about hCG action on VEGF in human endometrial cells is very thin. In the present study, we have examined microscopically hCG binding to dissociated human endometrial cells collected from mid-luteal phase and maintained in three-dimensional primary co-culture on rat-tail collagen type I biomatrix and examined the effect of different concentrations (0, 1, 10, 100 and 1000 IU/ML) of hCG on VEGF expression and secretion by endometrial cells maintained in the above system. We report that both cytokeratin positive epithelial cells as well as vimetin positive stromal cells from human mid luteal phase endometrium could bind hCG and that their number increased (P < 0.01) steadily with time. Administration of hCG enhanced (P < 0.05) immunoreactive VEGF protein expression in dose dependent manner in endometrial cells retrieved from mid-luteal phase of cycle, and co-cultured in a three-dimensional cell culture system, but with no marked change in VEGF secretion. Collectively, it appears that hCG influences VEGF protein synthesis in human midluteal phase endometrial cells, but has little effect on post-translational regulation and secretion. From physiological homeostasis point of view, it is likely that synthesis and secretion of VEGF exhibits a modular and factorial regulation to achieve a fine tuning of this potent vasotropic agent in receptive stage endometrium.  相似文献   
70.
BACKGROUND: Our present knowledge about trophoblast turnover in human first trimester placental villi based on multiparametric examination of proliferation and apoptosis is limited. METHODS: Human villous placentae collected during 6, 7 and 8 weeks (n = 10/each group) of gestation were examined for trophoblast proliferation and apoptosis based on quantitative analyses of immunopositive Fas, tumor necrosis factor receptor 1 (TNFR1), cytokeratin 18 fragment (18f), number of proliferating cell nuclear antigen (PCNA), Ki67 and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) positive nuclei, scores of mitotic and apoptotic indices and ultrastructural characteristics. RESULTS: Mitotic index in cytotrophoblast higher (P < 0.05) at 6 week compared with 7 and 8 weeks of gestation showed significant (P < 0.05) negative correlation between its prevalence and gestational age. Syncytiotrophoblast exhibited higher number of TUNEL positive nuclei (P < 0.01), TUNEL positive apoptotic nuclei (P < 0.05) and apoptotic index (P < 0.05) compared with cytotrophoblast at same gestational age. Positive correlations found between cytokeratin 18f and apoptotic index (P < 0.01), Fas and apoptotic index (P < 0.01), TUNEL positive nuclei and apoptotic index (P < 0.05), cytokeratin 18f and Fas (P < 0.01), whereas cytokeratin 18f (P < 0.05) and Fas (P < 0.05) showed positive correlation only with TUNEL positive apoptotic nuclear data. Phalangeal intrusions of syncytiotrophoblast between transitional cytotrophoblasts showed apposed plasma membranes bearing thickened membrane leaflets, inter-membranous gaps enclosing membranous invaginations, liposome-like particles; patches of membrane seen to be dissolved resulting in cytoplasmic continuity typical of syncytial formation. CONCLUSION: Cellular remodeling of first trimester villous placenta requires a complex homeodynamics involving proliferation in cytotrophoblast, development-associated syncytialization and apoptosis in syncytiotrophoblast.  相似文献   
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