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11.
BackgroundElectrocardiographic abnormalities, such as PR interval prolongation, have been anecdotally reported in patients with aortic root abscess (ARA). An electrocardiographic marker may be useful in identifying those patients with aortic valve endocarditis who may progress to ARA. The objective of this study is to evaluate the change in the PR interval in patients with surgically confirmed ARA and compare it to age‐ and gender‐matched controls with echocardiographically or surgically confirmed aortic valve endocarditis but without aortic root abscess and those hospitalized with diagnoses other than endocarditis.MethodsPatients were eligible for enrollment if they were 18 years or older and were hospitalized for either ARA, aortic valve endocarditis, or for unrelated reasons and had at least one 12‐lead electrocardiogram (ECG) prior to or on the day of hospitalization and at least one ECG after hospitalization but prior to any cardiac surgical procedure. Delta PR interval, defined as the difference between the pre‐ and post‐admission PR interval, was the primary outcome of interest. The patients in the ARA group were age‐ and gender‐matched to patients with aortic valve endocarditis and to those without endocarditis. Comparisons of demographic variables and study outcomes were performed.ResultsEighteen patients with surgically confirmed ARA were enrolled. These patients were age‐ and gender‐matched to 19 patients with aortic valve endocarditis and 18 patients with no past history or evidence of endocarditis during hospitalization. No difference was noted in the baseline PR interval between the groups. However, the PR interval following admission in the aortic root abscess group (201 ± 66 ms) was significantly longer than the PR interval in both the aortic valve endocarditis (162 ± 27 ms) (24%, p = .009) and no endocarditis (143 ± 24 ms) (40%, p < .001) groups. The primary outcome measure, delta PR interval, was significantly longer in the ARA group (35 ± 51 ms) than no endocarditis (−5 ± 17 ms) (p = .001) and aortic valve endocarditis groups (0.2 ± 18) (p = .003).ConclusionsThe findings of our study support the notion that the PR interval is more likely to be prolonged in patients with ARA. Since ARA is associated with a high morbidity and mortality, PR interval prolongation in a patient with aortic valve endocarditis should prompt a thorough evaluation for aortic root involvement.  相似文献   
12.
Inflammation and oxidative stress are important factors in the pathogenesis of diabetes and contribute to the pathogenesis of diabetic complications. Periodontitis is an inflammatory disease that is characterized by increased oxidative stress, and the risk for periodontitis is increased significantly in diabetic subjects. In this study, we examined the superoxide (O(2)(-))-generating reduced nicotinamide adenine dinucleotide phosphate-oxidase complex and protein kinase C (PKC) activity in neutrophils. Fifty diabetic patients were grouped according to glycemic control and the severity of periodontitis. Neutrophils from diabetic patients with moderate [amount of glycated hemoglobin (HbA(1c)) between 7.0% and 8.0%] or poor (HbA(1c) >8.0%) glycemic control released significantly more O(2)(-) than neutrophils from diabetic patients with good glycemic control (HbA(1c) <7.0%) and neutrophils from nondiabetic, healthy individuals upon stimulation with 4beta-phorbol 12-myristate 13-acetate or N-formyl-Met-Leu-Phe. Depending on glycemic status, neutrophils from these patients also exhibited increased activity of the soluble- and membrane-bound forms of PKC, elevated amounts of diglyceride, and enhanced phosphorylation of p47-phox during cell stimulation. In addition, we report a significant correlation between glycemic control (HbA(1c) levels) and the severity of periodontitis in diabetic patients, suggesting that enhanced oxidative stress and increased inflammation exacerbate both diseases. Thus, hyperglycemia can lead to a novel form of neutrophil priming, where elevated PKC activity results in increased phosphorylation of p47-phox and O(2)(-) release.  相似文献   
13.
Pseudo-angiomatous hyperplasia of mammary stroma (PASH) is a histopathological entity which is a microscopic fortuitous finding in mammary biopsies performed for different reasons. It may be symptomatic and appears then as a palpable lump. The term pseudo-angiomatous emphasizes the characteristic aspect of the stroma simulating a vascular tumor. We report a case of PASH in a 71 year-old woman who presented a recurring breast mass with rapid swelling of the mammary gland (70 x 60 x 20 cm) treated by mastectomy. PASH must be distinguished from a well-differentiated angiosarcoma. It is ruled out by immunohistochemistry.  相似文献   
14.
Human leukocyte antigen (HLA) haplotypes (n = 187) were genotyped and assigned by the mode of inheritance in migrant families from North Africa who reside in the Paris, France, area. The distribution of alleles and haplotypes in that population was compared with the one obtained in a control population of ancient French natives residing in the same area (248 independent haplotypes also assigned by the mode of inheritance were studied). The results in migrants reveal the following: (1) a higher diversity in the distribution of HLA-A and -DRB1 alleles; (2) lower frequencies of alleles common in our region, such as A*0201 B*1501, B*4001, and DRB1*0401 and increased frequencies of minor subtypes, such as A*3002 and DRB1*0402; and (3) distinct distributions of B/Cw, DRB1/DQB1 or B/Cw/DRB1/DQB1 haplotypes. The results also revealed that the four most frequent five-allele haplotypes in controls i.e., HLA-A*0101/B*0801/Cw*0701/DRB1*0301/DQB1*0201; A*0301/B*0702/Cw*0702/DRB1*1501/DQB1*0602 (both of Indo-Celtic origin); A*2902/B*4403/Cw*1601/DRB1*0701/DQB1*0202 (frequent in Western-Europeans); and A*0201/B*1501/Cw*0304/DRB1*0401/DQB1*0302, represent 10.5% of the total haplotypes in controls but 1.6% in North Africans. Conversely, 9 five-allele haplotypes in multiple copy in North Africans (among which A*3002/B*1801/Cw*0501/DRB1*0301/DQB1*0201 of Paleo-North African origin and A*0201/B*0702/Cw*0702/DRB1*1501/DQB1*0602 of ancient European and Paleo-North African origin) represent 9.6% of the total haplotypes in North Africans but 2.4% in controls. These results thus suggest a low degree of admixture between the two populations.  相似文献   
15.
Androgen-independent recurrence is the major limit of androgen ablation therapy for prostate cancer. Identification of alternative pathways promoting prostate tumor growth is thus needed. Stat5 has been recently shown to promote human prostate cancer cell survival/proliferation and to be associated with early prostate cancer recurrence. Stat5 is the main signaling pathway triggered by prolactin (PRL), a growth factor whose local production is also increased in high-grade prostate cancers. The first aim of this study was to use prostate-specific PRL transgenic mice to address the mechanisms by which local PRL induces prostate tumorogenesis. We report that (i) Stat5 is the major signaling cascade triggered by local PRL in the mouse dorsal prostate, (ii) this model recapitulates prostate tumorogenesis from precancer lesions to invasive carcinoma, and (iii) tumorogenesis involves dramatic accumulation and abnormal spreading of p63-positive basal cells, and of stem cell antigen-1–positive cells identified as a stem/progenitor-like subpopulation. Because basal epithelial stem cells are proposed to serve as tumor-initiating cells, we challenged the relevance of local PRL as a previously unexplored therapeutic target. Using a double-transgenic approach, we show that Δ1–9-G129R-hPRL, a competitive PRL-receptor antagonist, prevented early stages of prostate tumorogenesis by reducing or inhibiting Stat5 activation, cell proliferation, abnormal basal-cell pattern, and frequency or grade of intraepithelial neoplasia. This study identifies PRL receptor/Stat5 as a unique pathway, initiating prostate tumorogenesis by altering basal-/stem-like cell subpopulations, and strongly supports the importance of further developing strategies to target locally overexpressed PRL in human prostate cancer.  相似文献   
16.
Inflammatory pseudotumor (IPT) of the spleen is an uncommon entity with debated etiology, characterized by a mixture of inflammatory cells and a component of myofibroblastic spindle cells. This lesion needs to be distinguished from the follicular dendritic cell tumor and the inflammatory myofibroblastic tumor. We report two cases of splenic PTI in a 69-year old and a 62-year old women. The tumors measured respectively 80 and 30 mn in greatest dimension. An inflammatory pseudotumor was histopathologically diagnosed following a splenectomy.  相似文献   
17.
We have previously shown that, in normal human airway tissue, localization of the cystic fibrosis transmembrane conductance regulator (CFTR) can be affected by epithelial maturation, polarity, and differentiation and that CFTR trafficking and apical localization depend on the integrity of the airway epithelium. In this study, we addressed the question of whether the three-dimensional (3-D) organization of adult human airway epithelial cells in suspension culture under rotation, leading to spheroid-like structures, could mimic the in vivo phenomenon of differentiation and polarization. The kinetics of the differentiation, polarity, and formation of the CFTR-ZO-1-ezrin complex was analyzed by transmission, scanning, and immunofluorescence microscopy. Functional activity of the airway surface epithelium was assessed by monitoring the degree of cAMP-stimulated chloride efflux from cultured cells. Our results show that after the initial step of dedifferentiation, characterized by a loss of ciliated cells and disappearance of epithelial subapical CFTR-ezrin-ZO-1 complex, the isolated cells formed 3-D spheroid structures within 24 hours. After 15 days, progressive ciliogenesis was observed and secretory cells could be identified. After 35 days of 3-D culture, ZO-1, CFTR, ezrin, and CD59 were apically or subapically located, and well-differentiated secretory and ciliated cells were identified. CFTR functionality was assessed by analyzing the Cl(-) secretion after amiloride and forskolin perfusion. After 35 days of culture of spheroids in suspension, a significant increase in Cl(-) efflux was observed in well-differentiated ciliated cells.  相似文献   
18.
Primary ciliary dyskinesia (PCD) is a genetically heterogeneous disease of motile cilia. Even though PCD is widely studied, North‐African patients have been rarely explored. In this study, we aim at confirming the clinical diagnosis and explore the genetic spectrum of PCD in a cohort of Tunisian patients. Forty clinically diagnosed patients with PCD belonging to 34 families were recruited from Tunisian pediatric departments. In each proband, targeted capture PCD panel sequencing of the 40 PCD genes was performed. PCD panel sequencing identified bi‐allelic mutations in 82% of the families in eight PCD genes. Remarkably, 23.5% of patients carried the same c.2190del CCDC39 mutation. Single nucleotide polymorphism profiling in six unrelated patients carrying this mutation has revealed a founder effect in North‐African patients. This mutation is estimated to date back at least 1,400–1,750 years ago. The identification of this major allele allowed us to suggest a cost‐effective genetic diagnostic strategy in North‐African patients with PCD.  相似文献   
19.
20.
We report two cases of endometrial atypical complex hyperplasia with an extensive squamous hyperplasia occurring in two women aged 48 and 31 years old. The histological study showed an increase in the gland to stroma ratio with a false crowding aspect due to an extensive area of squamous metaplasia; some metaplastic areas were centered by necrosis. There was glandular cytologic atypia. Histologic examination is necessary to confirm the diagnosis and to definitively rule out adenocarcinoma.  相似文献   
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