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1.
We report a case of mucous gland adenoma arising in the left main bronchus which was initially misdiagnosed as asthma and review the previous reported cases of this rare tumor published in the available literature.  相似文献   
2.
Breast and ovarian cancer rates in Pakistan are significantly higher than in neighboring countries. The cancer rate discrepancies cannot be explained with discrepancies of their risk factors. We propose that observed cancer excess in Pakistan is due to cancer development by negative heterosis. Heterosis occurs when a hybrid has a phenotypic characteristic significantly different from that in either parent (hybrid vigor). At a molecular level, heterosis occurs in a heterozygote when one of the two alleles is inactivated. Gene inactivation occurs by methylation of cytosine in a promoter region of a gene. Initiation of allele inactivation is linked to the factors like stress, gender, diet, or another gene. In heterozygote, inactivation of one of the two tumor-suppressor alleles leads to monoallelic expression. This increases cancer risk in the same way the risk is increased in individual who inherit a single mutated tumor-suppressor gene (hereditary cancer syndrome). In both, cancer by heterosis and inherited cancer syndrome, cancer develops after inactivation of a second allele (second hit hypothesis). In a population, conditions that favor development of cancer by heterosis are those that favor mating of a large number of different homozygotes because they produce a large number of different heterozygotes. Among a large number of heterozygotes, there is an increased chance that some of hybrids will develop cancer by heterosis. In Pakistan, conditions were favorable for cancer development by heterosis because country has a high number of different ethnic groups and brotherhoods all of which have a higher rate of homozygosity due to a high frequency of consanguineous marriages, and marriages between members of different groups occurred because of intense population mixing. Result was birth of a large number of inter-ethnic/brotherhood hybrids (heterozygotes), some of which have developed cancer by heterosis.  相似文献   
3.
Positive influences of family members have been associated with a high probability of children’s daily breakfast consumption. Therefore, the aim of this study was to scrutinize the association of breakfast routines between mothers and their children. The baseline data of the Feel4Diabetes-study was obtained in 9760 children (49.05% boys)–mother pairs in six European countries. A parental self-reported questionnaire gauging the frequency of breakfast consumption and of breakfast´ foods and beverages consumption was used. Agreement in routines of mothers and their children’s breakfast consumption was analyzed in sex-specific crosstabs. The relationship of breakfast routine and food groups’ consumption between mothers and their children was assessed with analysis of covariance. The highest proportion of children who always consumed breakfast were those whose mothers always consumed it. Children consuming breakfast regularly had a higher intake of milk or unsweetened dairy products and all kind of cereal products (low fiber and whole-grain) than occasional breakfast consumers (p < 0.05). The strong similarity between mothers and children suggests a transfer of breakfast routine from mothers to their children, as a high proportion of children who usually consume breakfast were from mothers also consuming breakfast. All breakfast foods and beverages consumption frequencies were similar between children and their mothers.  相似文献   
4.
Objectives: The aim of this study was to assess the performance of echocardiographic parameters to predict response to cardiac resynchronization therapy (CRT). Background: CRT reduces morbidity and mortality due to the proper selection of candidates for CRT. Methods: The 12‐month trial was performed on 70 optimally medicated patients with standard inclusion criteria: NYHA class III or IV heart failure, left ventricular ejection fraction (LVEF) ≤ 35%, and QRS ≥ 120 ms. All parameters were evaluated by conventional and tissue Doppler‐based methods. Indicator of positive CRT response was more than 20% in improvement of LVEF. Results: LVEF increased >20% in 42 patients. Out of 43 tested baseline echocardiographic parameters, 12 showed statistical difference between responders and nonresponders. Out of these 12 parameters, six (LVSV, LVSI, LVFS, RVd, VPMR, and PISA) had modest to moderately good ability to predict LVEF response with sensitivity ranging from 62.2% to 82.4%, and specificity ranging from 56.5% to 81.2%. For those parameters, the area under the receiver‐operating characteristic curve for positive response to CRT was ≤0.76. Multivariate regression analysis resulted in selection of LVSI and LVFS as possible predictive independent parameters for a good response. The cutoff value for LVSI was 38.7 mL/m2 (P = 0.045) and for LVFS was 13% (P = 0.032). Conclusions: Contribution of LVSI and LVFS is to be confirmed in larger trials. Simplicity of their assessment by conventional echocardiography could be an argument for adding them to the inclusion criteria for CRT in severe heart failure patients. (Echocardiography 2012;29:267‐275)  相似文献   
5.
Vascular endothelium, as a key regulator of hemostasis, mediates vascular dilatation, prevents platelet adhesion, and inhibits thrombin generation. Endothelial dysfunction caused by acute or chronic inflammation, such as in atherosclerosis, creates a proinflammatory environment which supports leukocyte transmigration toward inflammatory sites, and at the same time promotes coagulation, thrombin generation, and fibrin deposition in an attempt to close the wound. Life-long persistent infection with human cytomegalovirus (HCMV) has been associated with atherosclerosis. In vivo studies have revealed that HCMV infection of the vessel wall affects various cells including monocytes/macrophages, smooth muscle cells (SMCs) and endothelial cells (ECs). HCMV-infected SMCs within vascular lesions display enhanced proliferation and impaired apoptosis, which contribute to intima-media thickening, plaque formation and restenosis. Monocytes play a central role in the process of viral dissemination, whereas ECs may represent a viral reservoir, maintaining persistent infection in HCMV-infected atherosclerotic patients following the primary infection. Persistent infection leads to dysfunction of ECs and activates proinflammatory signaling involving nuclear factor κB, specificity protein 1, and phosphatidylinositol 3-kinase, as well as expression of platelet-derived growth factor receptor. Activation of these pathways promotes enhanced proliferation and migration of monocytes and SMCs into the intima of the vascular wall as well as lipid accumulation and expansion of the atherosclerotic lesion. Moreover, HCMV infection induces enhanced expression of endothelial adhesion molecules and modifies the proteolytic balance in monocytes and macrophages. As a consequence, infected endothelium recruits naive monocytes from the blood stream, and the concomitant interaction between infected ECs and monocytes enables virus transfer to migrating monocytes. Endothelial damage promotes thrombin generation linking inflammation and coagulation. HCMV, in turn, enhances the thrombin generation. The virus carries on its surface the molecular machinery necessary to initiate thrombin generation, and in addition, may interact with the prothrombinase protein complex thereby facilitating thrombin generation. Thus, infection of endothelium may significantly increase the production of thrombin. This might not only contribute to thrombosis in patients with atherosclerosis, but might also induce thrombin-dependent proinflammatory cell activation. This review summarizes the existing evidence on the role of HCMV in vascular inflammation.  相似文献   
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7.
Neurocutaneous melanosis (NCM) is a rare, sporadic, congenital neuroectodermal dysplasia. Large congenital melanocytic nevi (CMN) can evolve in a certain percentage of patients to NCM. Meningeal deposits are benign, but can be prone to malignant transformation in some cases. We describe the case of an infant with asymptomatic NCM, and typical magnetic resonance imaging (MRI) findings. The diagnosis was established shortly after delivery, and the patient was followed for 60 months. At that time, the girl did not have any neurologic symptoms; she reached normal developmental milestones and did not show mental retardation and did not develop malignant melanoma; further follow‐up will be needed, although there are no reliable guidelines as to the time range of follow up of asymptomatic NCM in the literature. We report the typical MRI signal abnormalities of the brain, and present a review of the literature regarding this rare and mysterious congenital disorder.  相似文献   
8.
Rapid anti-suicidal and antidepressant effects of ketamine have repeatedly been confirmed in unipolar and bipolar depression. Although meaningful antidepressant efficacy of ketamine has also been shown in depressed patients with a history of psychotic symptoms, its administration in psychotic disorders has largely been neglected due to its potential to exacerbate dissociative or psychotic symptoms. Presenting a case of a young female inpatient suffering from schizophrenia with a severe post-psychotic depression, we demonstrate a robust anti-suicidal and antidepressant effect of S-ketamine infusions administered thrice weekly for 3 weeks in total. Importantly, no relevant psychotic or dissociative symptoms occurred during the whole augmentation treatment period leading to a sustained remission of depressive symptoms and suicidality. Our safe and effective experience with intravenous S-ketamine might encourage researchers and clinicians to widen its administration range beyond the diagnosis of depression to enrich the current knowledge of ketamine effects in psychotic disorders.  相似文献   
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10.
Aging is one of the major risk factors for Alzheimer’s disease (AD). Sirtuins are associated with prolonged life span. To examine whether the expression levels of sirtuins associate with the progression of AD or not, we performed a comparative immunoblotting and immunohistochemical study of SIRT1, 3, and 5 in the entorhinal cortex and hippocampal subregions and white matter in 45 cases grouped according to Braak and Braak stages of neurofibrillary degeneration. In addition, we compared the expression levels with the local load of tau and amyloid-beta deposits, evaluated using morphometry. Our study revealed that (1) the neuronal subcellular redistribution of SIRT1 parallels the decrease in its expression, suggesting stepwise loss of neuroprotection dependent on the neuronal population; (2) in contrast to SIRT1 and 3, expression of SIRT5 increases during the progression of AD; (3) which might be related to its appearance in activated microglial cells. The complex patterns of the expression of sirtuins in relation to tissue damage should be taken into account when searching for therapies interacting with sirtuins.  相似文献   
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