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31.
Coinheritance of germline mutation in cyclin‐dependent kinase inhibitor 2A (CDKN2A) and loss‐of‐function (LOF) melanocortin 1 receptor (MC1R) variants is clinically associated with exaggerated risk for melanoma. To understand the combined impact of these mutations, we established and tested primary human melanocyte cultures from different CDKN2A mutation carriers, expressing either wild‐type MC1R or MC1RLOF variant(s). These cultures expressed the CDKN2A product p16 (INK4A) and functional MC1R. Except for 32ins24 mutant melanocytes, the remaining cultures showed no detectable aberrations in proliferation or capacity for replicative senescence. Additionally, the latter cultures responded normally to ultraviolet radiation (UV) by cell cycle arrest, JNK, p38, and p53 activation, hydrogen peroxide generation, and repair of DNA photoproducts. We propose that malignant transformation of melanocytes expressing CDKN2A mutation and MC1RLOF allele(s) requires acquisition of somatic mutations facilitated by MC1R genotype or aberrant microenvironment due to CDKN2A mutation in keratinocytes and fibroblasts.  相似文献   
32.
A new species of pseudoscorpion, Amblyolpium atropatesi n. sp. is described and illustrated on the basis of the adult specimens extracted from soil by Berlese funnel.

http://www.zoobank.org/urn:lsid:zoobank.org:pub:0150B850-E80D-46F5-983C-7E958FE69B87  相似文献   

33.
Despite advanced diagnostic techniques used for detecting cancer, this disease still remains a leading cause of death in the developed world. What is more, the greatest danger for patients is not related with growing of tumor but rather with metastasis of cancer cells to the distant organs. In this study, Fourier transform infrared (FTIR) spectroscopy was used to track chemical changes in blood plasma to find spectral markers of metastatic breast cancer during the disease progression. Plasma samples were taken 1‐5 weeks after orthotropic inoculation of 4T1 metastatic breast cancer cells to mice. The earliest changes detected by FTIR spectroscopy in plasma were correlated with unsaturation of phospholipids and secondary structures of proteins that appeared 2 and 3 weeks, respectively, after 4T1 cells inoculation (micrometastatic phase). Significant alternations in the content and structure of lipids and carbohydrates were identified in plasma at the later stages (macrometastatic phase). When large primary tumors in breast and macrometastases in lung were developed, all bands in FTIR spectra significantly differed from those at earlier phases of the cancer progression. In conclusion, we showed that each phase of the breast cancer progression and its pulmonary metastasis can be characterized by a specific panel of spectral markers.  相似文献   
34.
Collagen fibrils, a major component of mitral valve leaflets, play an important role in defining shape and providing mechanical strength and flexibility. Histopathological studies show that collagen fibrils undergo dramatic changes in the course of myxomatous mitral valve disease in both dogs and humans. However, little is known about the detailed organization of collagen in this disease. This study was designed to analyze and compare collagen fibril organization in healthy and lesional areas of myxomatous mitral valves of dogs, using synchrotron small-angle x-ray diffraction. The orientation, density, and alignment of collagen fibrils were mapped across six different valves. The findings reveal a preferred collagen alignment in the main body of the leaflets between two commissures. Qualitative and quantitative analysis of the data showed significant differences between affected and lesion-free areas in terms of collagen content, fibril alignment, and total tissue volume. Regression analysis of the amount of collagen compared to the total tissue content at each point revealed a significant relationship between these two parameters in lesion-free but not in affected areas. This is the first time this technique has been used to map collagen fibrils in cardiac tissue; the findings have important applications to human cardiology.  相似文献   
35.
An important role has been recently reported for bacterial biofilm in the pathophysiology of chronic diseases, such as chronic rhinosinusitis (CRS). CRS, affecting sinonasal mucosa, is a persistent inflammatory condition with a high prevalence around the world. Although the exact pathological mechanism of this disease has not been elicited yet, biofilm formation is known to lead to a more significant symptom burden and major objective clinical indicators. The high prevalence of multidrug-resistant bacteria has severely restricted the application of antibiotics in recent years. Furthermore, systemic antibiotic therapy, on top of its insufficient concentration to eradicate bacteria in the sinonasal biofilm, often causes toxicity, antibiotic resistance, and an effect on the natural microbiota, in patients. Thus, coming up with alternative therapeutic options instead of systemic antibiotic therapy is emphasized in the treatment of bacterial biofilm in CRS patients. The use of topical antibiotic therapy and antibiotic eluting sinus stents that induce higher antibiotic concentration, and decrease side effects could be helpful. Besides, recent research recognized that various natural products, nitric oxide, and bacteriophage therapy, in addition to the hindered biofilm formation, could degrade the established bacterial biofilm. However, despite these improvements, new antibacterial agents and CRS biofilm interactions are complicated and need extensive research. Finally, most studies were performed in vitro, and more preclinical animal models and human studies are required to confirm the collected data. The present review is specifically discussing potential therapeutic strategies for the treatment of bacterial biofilm in CRS patients.  相似文献   
36.
The cancer stem cell (CSC) model encompasses an advantageous paradigm that in recent decades provides a better elucidation for many important biological aspects of cancer initiation, progression, metastasis, and, more important, development of multidrug resistance (MDR). Such several other hematological malignancies and solid tumors and the identification and isolation of ovarian cancer stem cells (OV-CSCs) show that ovarian cancer also follows this hierarchical model. Gaining a better insight into CSC-mediated resistance holds promise for improving current ovarian cancer therapies and prolonging the survival of recurrent ovarian cancer patients in the future. Therefore, in this review, we will discuss some important mechanisms by which CSCs can escape chemotherapy, and then review the recent and growing body of evidence that supports the contribution of CSCs to MDR in ovarian cancer.  相似文献   
37.
The hypoxic niche of tumor leads to a tremendous increase in the extracellular adenosine concentration through alteration of adenosine metabolism in the tumor microenvironment (TME). This consequently affects cancer progression, local immune responses, and apoptosis of tumor cells. Regulatory effect of adenosine on apoptosis in TME depends on the cancer cell type, pharmacological characteristics of adenosine receptor subtypes, and the adenosine concentration in the tumor niche. Exploiting specific pharmacological adenosine receptor agonist and antagonist inducing apoptosis in cancer cells can be considered as a proper procedure to control cancer progression. This review summarizes the regulatory role of adenosine in cancer cell apoptosis for a better understanding, and hence better management of the disease.  相似文献   
38.
Helicobacter pylori (H. pylori) causes gastric mucosa inflammation and gastric cancer mostly via several virulence factors. Induction of proinflammatory pathways plays a crucial role in chronic inflammation, gastric carcinoma, and H. pylori pathogenesis. Herbal medicines (HMs) are nontoxic, inexpensive, and mostly anti-inflammatory reminding meticulous emphasis on the elimination of H. pylori and gastric cancer. Several HM has exerted paramount anti-H. pylori traits. In addition, they exert anti-inflammatory effects through several cellular circuits such as inhibition of 5′-adenosine monophosphate-activated protein kinase, nuclear factor-κB, and activator protein-1 pathway activation leading to the inhibition of proinflammatory cytokines (interleukin 1α [IL-1α], IL-1β, IL-6, IL-8, IL-12, interferon γ, and tumor necrosis factor-α) expression. Furthermore, they inhibit nitrous oxide release and COX-2 and iNOS activity. The apoptosis induction in Th1 and Th17-polarized lymphocytes and M2-macrophagic polarization and STAT6 activation has also been exhibited. Thus, their exact consumable amount has not been revealed, and clinical trials are needed to achieve optimal concentration and their pharmacokinetics. In the aspect of bioavailability, solubility, absorption, and metabolism of herbal compounds, nanocarriers such as poly lactideco-glycolide-based loading and related formulations are helpful. Noticeably, combined therapies accompanied by probiotics can also be examined for better clearance of gastric mucosa. In addition, downregulation of inflammatory microRNAs (miRNAs) by HMs and upregulation of those anti-inflammatory miRNAs is proposed to protect the gastric mucosa. Thus there is anticipation that in near future HM-based formulations and proper delivery systems are possibly applicable against gastric cancer or other ailments because of H. pylori.  相似文献   
39.
Prostate cancer is a major cause of cancer-related death in males. Wnt/β-catenin signaling plays a critical role in the pathogenesis of this disease by regulating angiogenesis, drug resistance, cell proliferation, and apoptosis. Suppression of Wnt canonical or noncanonical signaling pathways via Wnt biological or pharmacological antagonists is a potentially novel therapeutic approach for patients with prostate cancer. This review summarizes the role of Wnt signaling inhibitors in the pathogenesis of prostate cancer for a better understanding and hence a better management of this disease.  相似文献   
40.
Inflammation is a normal part of the immune response to injury or infection but its dysregulation promotes the development of inflammatory diseases, which cause considerable human suffering. Nonsteroidal anti-inflammatory agents are the most commonly prescribed agents for the treatment of inflammatory diseases, but they are accompanied by a broad range of side effects, including gastrointestinal and cardiovascular events. The renin–angiotensin system (RAS) is traditionally known for its role in blood pressure regulation. However, there is increasing evidence that RAS signaling is also involved in the inflammatory response associated with several disease states. Angiotensin II increases blood pressure by binding to angiotensin type 1 (AT1) receptor, and direct renin inhibitors, angiotensin-converting enzyme (ACE) inhibitors and AT1 receptor blockers (ARBs) are clinically used as antihypertensive agents. Recent data suggest that these drugs also have anti-inflammatory effects. Therefore, this review summarizes these recent findings for the efficacy of two of the most widely used antihypertensive drug classes, ACE inhibitors and ARBs, to reduce or treat inflammatory diseases such as atherosclerosis, arthritis, steatohepatitis, colitis, pancreatitis, and nephritis.  相似文献   
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