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21.
Nobiletin, a bioactive polymethoxylated flavone (5,6,7,8,3',4'‐hexamethoxyflavone), is abundant in citrus fruit peel. Although nobiletin exhibits antitumor activity against various cancer cells, the effect of nobiletin on glioma cells remains unclear. The aim of this study was to determine the effects of nobiletin on the human U87 and Hs683 glioma cell lines. Treating glioma cells with nobiletin (20–100 µm ) reduced cell viability and arrested the cell cycle in the G0/G1 phase, as detected using a 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay and propidium iodide (PI) staining, respectively; however, nobiletin did not induce cell apoptosis according to PI‐annexin V double staining. Data from western blotting showed that nobiletin significantly attenuated the expression of cyclin D1, cyclin‐dependent kinase 2, cyclin‐dependent kinase 4, and E2 promoter‐binding factor 1 (E2F1) and the phosphorylation of Akt/protein kinase B and mitogen‐activated protein kinases, including p38, extracellular signal‐regulated kinase, and c‐Jun N‐terminal kinase. Our data also showed that nobiletin inhibited glioma cell migration, as detected by both functional wound healing and transwell migration assays. Altogether, the present results suggest that nobiletin inhibits mitogen‐activated protein kinase and Akt/protein kinase B pathways and downregulates positive regulators of the cell cycle, leading to subsequent suppression of glioma cell proliferation and migration. Our findings evidence that nobiletin may have potential for treating glioblastoma multiforme. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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23.
Cardiac metabolism is finely tuned, and disruption of myocardial bioenergetics can be clinically devastating. Many cardiomyopathies that present early in life are due to disruption of the maturation of these metabolic pathways. However, this bioenergetic maturation begins well before birth, when the embryonic heart is first beginning to beat, and continues into the mature animal. Thus, the changes in energy production seen after birth are actually part of a continuum that coincides with the structural and functional changes that occur as the cardiac myocyte differentiates and the heart undergoes morphogenesis. Therefore, although bioenergetics and mitochondrial biology have not been studied in great detail in the developing heart, bioenergetic maturation should be considered an important component of normal myocyte differentiation.Although events occurring after birth will be discussed, this review will focus on the changes in bioenergetics and mitochondrial biology that coincide with myocyte differentiation and cardiac morphogenesis. The relationship of these changes to the etiology and presentation of cardiomyopathies will be used as a starting point for this discussion. Then, after reviewing cardiac development and mitochondrial biology, the published data on bioenergetics and mitochondrial structure and function in the developing heart will be presented. Finally, the case will be made that mitochondria may be critical regulators of cardiac myocyte differentiation and cardiac development.  相似文献   
24.
ObjectivesToll-like receptors (TLRs) are molecules conserved in evolution for detecting pathogen invasions and tissue damage and are involved in atherogenesis. This study explores the mRNA expression of TLRs and their probable role in further disease occurrence among ischemic stroke patients.Design and MethodsA total of 89 ischemic stroke patients and 166 controls were recruited for this study. Total RNA was extracted and mRNA was reverse-transcribed to cDNA and was analyzed for TLRs and interleukin 8 (IL8).ResultsThe TLR4 mRNA expression level is significantly higher in the stroke group. Conversely, IL-8 mRNA levels decreased significantly in the patient group.ConclusionOur results suggest that TLR4 overexpression in mRNA levels is observed in stroke patients, which might account for the probable inflammatory injury before or after stroke. A reduction of IL-8 expression could result from the downregulatory effects of aspirin.  相似文献   
25.

Background  

We assessed whether the esophageal mucosa index of hemoglobin (IHb) could assist the Los Angeles (LA) classification in defining the severity of erosive reflux esophagitis (RE) and predicting the treatment response by esomeprazole.  相似文献   
26.
The M2 blockers amantadine and rimantadine and the neuraminidase (NA) inhibitors (NAIs) oseltamivir and zanamivir are approved by the FDA for use for the control of influenza A virus infections. The 2009 pandemic influenza A (H1N1) viruses (H1N1pdm) are reassortants that acquired M and NA gene segments from a Eurasian adamantane-resistant swine influenza virus. NAI resistance in the H1N1pdm viruses has been rare, and its occurrence is mainly limited to oseltamivir-exposed patients. The pyrosequencing assay has been proven to be a useful tool in surveillance for drug resistance in seasonal influenza A viruses. We provide a protocol which allows the detection of adamantane resistance markers as well as the I43T change, which is unique to the H1N1pdm M2 protein. The protocol also allows the detection of changes at residues V116, I117, E119, Q136, K150, D151, D199, I223, H275, and N295 in the NA, known to alter NAI drug susceptibility. We report on the detection of the first cases of the oseltamivir resistance-conferring mutation H275Y and the I223V change in viruses from the United States using the approach described in this study. Moreover, the assay permits the quick identification of the major NA group (V106/N248, I106/D248, or I106/N248) to which a pandemic virus belongs. Pyrosequencing is well suited for the detection of drug resistance markers and signature mutations in the M and NA gene segments of the pandemic H1N1 influenza viruses.In the spring of 2009, an antigenically novel influenza A virus (H1N1) was detected in North America (7). The rapid widespread transmission of the virus resulted in the declaration of an influenza pandemic by the World Health Organization (WHO) (42). The 2009 pandemic influenza A (H1N1) virus (H1N1pdm) was determined to be a reassortant with a combination of gene segments that had not been previously described (12, 21). Phylogenetic analysis of the full genome sequences revealed that in the late 1990s, reassortment between seasonal influenza A virus (H3N2), classical swine influenza virus, and North American avian influenza viruses led to the appearance of triple-reassortant H3N2 and H1N2 swine influenza viruses that have since circulated in pigs in North America (40). The pandemic virus was a result of further reassortment between a triple-reassortant swine influenza virus and a Eurasian avian influenza virus-like swine influenza virus, resulting in the acquisition of two gene segments, coding for the M protein and neuraminidase (NA), from the Eurasian avian influenza virus-like swine influenza virus lineage. Recent genome sequence analysis performed with pandemic viruses collected in different regions found variants with characteristic amino acid changes, including 2 amino acid changes in the NA (21, 29). The reports identified three NA variants among the H1N1pdm viruses: one variant group has V106 and N248 (referred to as the A/California/04/2009 group); the second variant, named the A/Osaka/164/2009 group, is characterized by I106 and N248; and the third NA variant group contains I106 and D248, such as the A/New York/18/2009 strain.Currently circulating triple-reassortant swine influenza viruses in the United States do not contain any known markers of adamantane resistance (L26F, V27A, A30V, A30T, S31N, and G34E) (10, 25), whereas the Eurasian avian-like influenza viruses as well as the pandemic virus contain the adamantane resistance-conferring change S31N in the M2 protein. Currently, two classes of antiviral drugs are approved for use by the FDA for the control of influenza virus infections: adamantanes (M2 blockers) and neuraminidase inhibitors (NAIs). Resistance to adamantanes makes the NAIs oseltamivir and zanamivir the only pharmaceutical options available for use for the control of infections caused by the pandemic virus. Monitoring of resistance to NAIs is mainly based on the NA inhibition assay (23, 39, 41), which allows the detection of resistance conferred by known and novel mutations. However, the NA inhibition assay requires virus isolation and propagation, and the detection of resistance by the NA inhibition assay requires confirmation by sequencing of the NA gene segment to identify the markers of resistance and their presence in the original clinical material.Prior to the 2007-2008 influenza season, the frequency of resistance to NAIs had been very low (<0.5%) among field isolates (28, 35, 36). During the 2007-2008 influenza season, seasonal H1N1 viruses resistant to oseltamivir emerged and spread globally (3, 17, 31, 39), and by April of 2009, the majority of the H1N1 viruses were resistant to oseltamivir but sensitive to zanamivir. Of note, nearly all of the 2009 pandemic H1N1 viruses were sensitive to NAIs (8); only sporadic cases of oseltamivir-resistant viruses with the H275Y mutation in the NA gene segment were reported to the WHO, and they were mainly detected following antiviral drug treatment (5, 6, 42). The H275Y mutation is equivalent to the H274Y mutation in the N2 subtype amino acid numbering. Throughout the text, amino acids are described with the N1 numbering, and the corresponding N2 amino acid numbering is shown in parentheses, when it differs from the N1 numbering. Recent reports on the emergence of oseltamivir resistance highlight the need for close monitoring of the susceptibility of the pandemic H1N1 virus to the available drugs (5, 6, 42). Such information is needed to make informed decisions on measures aimed at managing pandemic virus infections.The molecular markers of NAI resistance are type and subtype specific and are also drug specific (1, 23). The H275Y (H274Y) change is the most commonly reported mutation conferring resistance to oseltamivir in the N1 subtype of NA. This change has been reported not only in seasonal H1N1 viruses but also in highly pathogenic H5N1 viruses (13, 22, 23, 31, 33). The H275Y (H274Y) mutation is also known to reduce susceptibility to the investigational NAI peramivir (23). The amino acid replacement N295S (N294S) in N1 has also been shown to reduce susceptibility to oseltamivir and zanamivir (33, 43). In addition, recent studies have demonstrated that mutations in other residues located in and around the NA active site can alter the susceptibilities of viruses to NAIs. For instance, changes at residues V116, I117, E119, Q136, D199 (D198), and I223 (I222) were associated with reduced susceptibility to NAIs in both seasonal and H5N1 viruses (26-28, 30, 32, 39). Moreover, crystal structure studies with the NAs of H1N1 and H5N1 viruses (9, 37) suggested that mutations at amino acids Q136, K150, and D151 (37) may affect susceptibility to oseltamivir and zanamivir, presumably by interfering with the binding of the drug to the NA. Changes at these residues were reported to reduce the susceptibilities to NAIs of viruses with the N1 enzyme (34; CDC, Atlanta, GA, unpublished data).It is important to develop the tools necessary for the rapid detection of NA markers known or suspected of affecting susceptibility to NAIs. Pyrosequencing has previously been shown to provide a rapid and high-throughput method for the detection of molecular markers of drug resistance in seasonal as well as highly pathogenic avian influenza viruses (4, 8, 15, 16, 19, 30, 31, 38).Here we report on the design and validation of pyrosequencing assays for the detection of signature markers in the M2 and NA gene segments of the pandemic H1N1 viruses.  相似文献   
27.
This study examined the effect of progressive muscle relaxation (PMR) on blood pressure and psychosocial status in clients with essential hypertension. The study, which used a quasi-experimental design, recruited a convenience sample of 40 subjects from a hypertension outpatient clinic. Twenty subjects received PMR training once a week and practiced at home daily for 4 weeks. PMR training had an immediate effect, reducing pulse rate 2.35 beats/min, systolic blood pressure 5.44 mm Hg, and diastolic blood pressure 3.48 mm Hg. After 4 weeks of PMR training, further decreases in pulse rate (2.9 beats/min), systolic blood pressure (5.1 mm Hg), and diastolic blood pressure (3.1 mm Hg) occurred. PMR significantly lowered patients' perception of stress, and it enhanced their perception of health. PMR is beneficial for patients with essential hypertension, and nurses may use it to enhance their independent function as well as their quality of life.  相似文献   
28.
Initial clinical practice is stressful. Nursing students entering clinical practice for the first time in a five-year associate degree program in Taiwan are young and have questionable coping skills, all of which can affect their own health. This study examined the following: (1) the degree of stress perceived and types of stressful events; (2) the physio-psycho-social status of nursing students during the practice; (3) the coping behaviors of these students; and (4) the effect of different coping behaviors on their physio-psycho-social health. The subjects were 561 nursing students who had completed their initial clinical practice at the largest nursing school in Taiwan. Three measurements, including Perceived Stress Scale (PSS), Physio-Psycho-Social Response Scale (PPSRS), and Coping Behavior Inventory (CBI), were adopted. Results showed that stress for these students came mainly from the lack of professional knowledge and skills as well as caring of patients. The most common response to stress was social behavioral symptoms. Staying optimistic had a positive main effect, which reduced the occurrence of physio-psycho-social symptoms and improved physio-psycho-social status. Finally, problem-solving behavior also had a positive main effect, while avoidance had a negative main effect, which deteriorated physio-psycho-social status. This study has important implications for nursing educators in helping their students to overcome stress during clinical practice.  相似文献   
29.
Molecular therapy studies to date have examined only a limited number of corrective parameters. To assess more global impacts on cellular gene expression for two major molecular therapeutic approaches, we compared gene versus protein delivery in the human genetic disease junctional epidermolysis bullosa (JEB). Both gene and protein replacement of the laminin 5 beta3 (beta3) adhesion molecule restored normal growth and adhesion to poorly viable JEB cells. Gene expression profiling was then performed using cDNA microarrays. The expression of more genes was normalized after beta3 gene transfer than after protein transfer. As anticipated for beta3 delivery, many of the genes whose expression was restored to the normal range were those encoding adhesion molecules and hemidesmosome components. Although gene transfer normalized the expression of a higher percentage of genes than did protein transfer, neither approach fully normalized expression of all genes examined. In addition, both approaches disrupted the expression of some genes, but protein transfer altered expression of a larger proportion of the genes studied. Our findings suggest that therapeutic gene and protein delivery may exert different effects on gene expression and thus may have implications for the development and analysis of molecular therapies for the treatment of genetic disorders.  相似文献   
30.
Lead remains a significant environmental toxin, and we believe we may have identified a novel target of lead toxicity in articular chondrocytes. These cells are responsible for the maintenance of joint matrix, and do so under the regulation of TGF‐β signaling. As lead is concentrated in articular cartilage, we hypothesize that it can disrupt normal chondrocyte phenotype through suppression of TGF‐β signaling. These experiments examine the effects of lead exposure in vivo and in vitro at biologically relevant levels, from 1 nM to 10 µM on viability, collagen levels, matrix degrading enzyme activity, TGF‐β signaling, and articular surface morphology. Our results indicate that viability was unchanged at levels ≤100 µM Pb, but low and high level lead in vivo exposure resulted in fibrillation and degeneration of the articular surface. Lead treatment also decreased levels of type II collagen and increased type X collagen, in vivo and in vitro. Additionally, MMP13 activity increased in a dose‐dependent manner. Active caspase 3 and 8 were dose‐dependently elevated, and treatment with 10 µM Pb resulted in increases of 30% and 500%, respectively. Increasing lead treatment resulted in a corresponding reduction in TGF‐β reporter activity, with a 95% reduction at 10µM. Levels of phosphoSmad2 and 3 were suppressed in vitro and in vivo and lead dose‐dependently increased Smurf2. These changes closely parallel those seen in osteoarthritis. Over time this phenotypic shift could compromise maintenance of the joint matrix. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 30:1760–1766, 2012  相似文献   
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