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The skin of most mammals is characterised by the presence of sebaceous glands (SGs), whose predominant constituent cell population is sebocytes, that is, lipid‐producing epithelial cells, which develop from the hair follicle. Besides holocrine sebum production (which contributes 90% of skin surface lipids), multiple additional SG functions have emerged. These range from antimicrobial peptide production and immunomodulation, via lipid and hormone synthesis/metabolism, to the provision of an epithelial progenitor cell reservoir. Therefore, in addition to its involvement in common skin diseases (e.g. acne vulgaris), the unfolding diversity of SG functions, both in skin health and disease, has raised interest in this integral component of the pilosebaceous unit. This practical guide provides an introduction to SG biology and to relevant SG histochemical and immunohistochemical techniques, with emphasis placed on in situ evaluation methods that can be easily employed. We propose a range of simple, established markers, which are particularly instructive when addressing specific SG research questions in the two most commonly investigated species in SG research, humans and mice. To facilitate the development of reproducible analysis techniques for the in situ evaluation of SGs, this methods review concludes by suggesting quantitative (immuno‐)histomorphometric methods for standardised SG evaluation.  相似文献   
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Chronic lymphocytic leukemia (CLL) remains an incurable malignancy, urging for the identifcation of new molecular targets for therapeutic intervention. CLL cells rely on overexpression and hyperactivation of the ubiquitous serine/threonine protein kinase CK2 for their viability in vitro. CIGB-300 is a cell-permeable selective CK2 inhibitor peptide undergoing clinical trials for several cancers. Here, we show that CIGB-300 promotes activation of the tumor suppressor PTEN and abrogates PI3K-mediated downstream signaling in CLL cells. In accordance, CIGB-300 decreases the viability and proliferation of CLL cell lines, promotes apoptosis of primary leukemia cells and displays antitumor efcacy in a xenograft mouse model of human CLL. Our studies provide pre-clinical support for the testing and possible inclusion of CK2 inhibitors in the clinical arsenal against CLL.  相似文献   
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The epidermis of the skin is a multilayered stratified epithelium whose primary function is to provide a barrier against our external environment. As a result, cells in the epidermis are subject to constant assault from environmental pathogens, many of which can cause deleterious mutations. However, most of these mutations do not lead to skin cancer. One explanation is that most genetic hits are sustained by mature or transit cells with limited proliferative capacity and only stem cells that acquire genetic alterations have the potential to propagate a frank tumor. In this mini-review we will discuss recent studies that provide some of the first genetic evidence to support a stem cell origin for a number of skin cancer types.  相似文献   
37.
Prenatal exposure to chlorpyrifos (CPF), an organophosphorus insecticide, has long been associated with delayed neurocognitive development and most recently with decrements in working memory at age 7. In the current paper, we expanded the previous work on CPF to investigate how additional biological and social environmental factors might create or explain differential neurodevelopmental susceptibility, focusing on main and moderating effects of the quality of the home environment (HOME) and child sex. We evaluate how the quality of the home environment (specifically, parental nurturance and environmental stimulation) and child sex interact with the adverse effects of prenatal CPF exposure on working memory at child age 7years. We did not observe a remediating effect of a high quality home environment (either parental nurturance or environmental stimulation) on the adverse effects of prenatal CPF exposure on working memory. However, we detected a borderline significant interaction between prenatal exposure to CPF and child sex (B (95% CI) for interaction term=-1.714 (-3.753 to 0.326)) suggesting males experience a greater decrement in working memory than females following prenatal CPF exposure. In addition, we detected a borderline interaction between parental nurturance and child sex (B (95% CI) for interaction term=1.490 (-0.518 to 3.499)) suggesting that, in terms of working memory, males benefit more from a nurturing environment than females. To our knowledge, this is the first investigation into factors that may inform an intervention strategy to reduce or reverse the cognitive deficits resulting from prenatal CPF exposure.  相似文献   
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Hyperglycemia and compromised β-cell development were demonstrated in neonatal rats programmed with a gestational high-fat diet. The aim of this study was to determine whether these changes were attributed to impaired insulin release and altered immunoreactivity of Pdx-1, glucokinase (GK), and glucose transporter (GLUT)–2 in high-fat–programmed neonates. Fetuses were maintained, via maternal nutrition, on either a standard laboratory diet (control) or a high-fat diet throughout gestation (HFG). Pancreata from 1-day–old neonates were excised for islet isolation and the subsequent measurement of insulin release at 2.8, 6.5, 13, and 22 mmol/L glucose. Other pancreata were either snap frozen for quantitative polymerase chain reaction or formalin fixed for immunohistochemistry followed by image analysis. The HFG neonates had reduced insulin release at 13- and 22-mmol/L glucose concentrations. No significant differences were found in Pdx-1, GK, or GLUT-2 messenger RNA expression. In HFG neonates, immunoreactivity of both Pdx-1 and GK was significantly reduced, with a nonsignificant reduction in GLUT-2. Gestational high-fat programming impairs insulin release and reduces Pdx-1 and GK immunoreactivity.  相似文献   
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Aims/hypothesis  

We compared the effect of biphasic, basal or prandial insulin regimens on glucose control, clinical outcomes and adverse events in people with type 2 diabetes.  相似文献   
40.
Subepicardial aneurysms (SEA) are an infrequent and serious form of subacute cardiac rupture complicating myocardial infarction. An early diagnosis and surgical repair may be life saving. SEA comprise an abrupt interruption of the myocardium, with a narrow neck and thin wall containing only the epicardium. It may progress to fatal cardiorrhexis. We describe the echocardiographic evolution of this type of cardiac rupture and the contribution of contrast-enhanced echocardiography. A possible pathophysiological mechanism is proposed.  相似文献   
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