275 research outputs found

    Autophagy in Multidrug-Resistant Cancers

    Get PDF
    Multidrug resistance (MDR) in cancers is the major challenge in cancer therapy, thus the development of sensitizing agents or small molecules with new mechanisms of action to kill the resistant cancers is highly desired. Autophagy is a cellular process responsible for the turnover of misfolded proteins or damaged organelles and recycling of nutrients to maintain cellular homeostasis. Recently, autophagy has been shown to regulate MDR in cancers. In this chapter, both intrinsic and acquired drug resistance affecting the efficiency of chemotherapy, and the MDR mechanisms including nonclassical MDR phenotype and classical transport-based MDR phenotype were discussed. In addition, the development of apoptosis-resistant cancer by the deregulation of apoptotic gene machinery, such as BCL-2, BAX, BAK, and TRAILR, was also covered. We then further discussed the controversial role of autophagy by illustrating how induction of autophagy could work as a tumor suppressor or promote tumor survival. The modulation of MDR in cancer by either induction or inhibition of autophagy was also discussed. We have further summarized the current compounds or drugs for modulating MDR cancers and how autophagy modulators could circumvent the MDR phenotypes in cancers. Finally, the new mechanisms participating in MDR phenotypes were proposed for future MDR drugs discovery

    Immunotherapeutic Approaches of Rheumatoid Arthritis and the Implication on Novel Interventions for Refractoriness

    Get PDF
    Rheumatoid arthritis is an autoimmune disorder involving the chronic inflammation of affected joints which lead to the distortion and eventually destruction of the articular tissues. Clinically, many therapeutic methods are being used for RA treatment. Non-steroidal anti-inflammatory drugs (NSAIDs), steroid, and disease-modifying anti-rheumatic drugs (DMARDs) are the three main categories of intervention approaches. Among which DMARDs, targeting mainly the release of pro-inflammatory cytokines, demonstrated high efficacy because of its direct drug action that alter the underlying disease mechanisms rather than simply to mediate symptoms relieve. However, the use of DMARDs also accompanying some unwanted adverse side effects, in particular, the development of refractoriness, which hampers the successful rate of treatment. In this chapter, the conventional RA drugs will be reviewed, focusing on the currently used and latest development of DMARDs. Novel methods that could improve RA pathogenesis will also be introduced. Because of the critical role of refractory RA, the progress of the disease to develop resistance to standard drug treatment will also be described. Finally, innovative RA therapeutic methods inspired by researches concerning the pathogenesis and contemporary treatments of RA will be discussed

    Development of Level 1b Calibration and Validation Readiness, Implementation and Management Plans for GOES-R

    Get PDF
    A complement of Readiness, Implementation and Management Plans (RIMPs) to facilitate management of post-launch product test activities for the official Geostationary Operational Environmental Satellite (GOES-R) Level 1b (L1b) products have been developed and documented. Separate plans have been created for each of the GOES-R sensors including: the Advanced Baseline Imager (ABI), the Extreme ultraviolet and X-ray Irradiance Sensors (EXIS), Geostationary Lightning Mapper (GLM), GOES-R Magnetometer (MAG), the Space Environment In-Situ Suite (SEISS), and the Solar Ultraviolet Imager (SUVI). The GOES-R program has implemented these RIMPs in order to address the full scope of CalVal activities required for a successful demonstration of GOES-R L1b data product quality throughout the three validation stages: Beta, Provisional and Full Validation. For each product maturity level, the RIMPs include specific performance criteria and required artifacts that provide evidence a given validation stage has been reached, the timing when each stage will be complete, a description of every applicable Post-Launch Product Test (PLPT), roles and responsibilities of personnel, upstream dependencies, and analysis methods and tools to be employed during validation. Instrument level Post-Launch Tests (PLTs) are also referenced and apply primarily to functional check-out of the instruments

    GOES-R L1b Readiness Implementation and Management Plan

    Get PDF
    A complement of Readiness, Implementation and Management Plans (RIMPs) to facilitate management of post-launch product test activities for the official Geostationary Operational Environmental Satellite (GOES-R) Level 1b (L1b) products have been developed and documented. Separate plans have been created for each of the GOES-R sensors including: the Advanced Baseline Imager (ABI), the Extreme ultraviolet and X-ray Irradiance Sensors (EXIS), Geostationary Lightning Mapper (GLM), GOES-R Magnetometer (MAG), the Space Environment In-Situ Suite (SEISS), and the Solar Ultraviolet Imager (SUVI). The GOES-R program has implemented these RIMPs in order to address the full scope of CalVal activities required for a successful demonstration of GOES-R L1b data product quality throughout the three validation stages: Beta, Provisional and Full Validation. For each product maturity level, the RIMPs include specific performance criteria and required artifacts that provide evidence a given validation stage has been reached, the timing when each stage will be complete, a description of every applicable Post-Launch Product Test (PLPT), roles and responsibilities of personnel, upstream dependencies, and analysis methods and tools to be employed during validation. Instrument level Post-Launch Tests (PLTs) are also referenced and apply primarily to functional check-out of the instruments

    Survey of oral hygiene behaviour, knowledge and oral hygiene status among Hong Kong adults : a pilot study

    Get PDF
    Objectives: To study the correlation between oral health behaviour and knowledge with respect to the oral hygiene status of Hong Kong Chinese adults. Materials and methods: Subject selection was by convenience sampling. A total of four outreach visits were arranged in March 2015. The participants’ oral health behavior and knowledge were evaluated through a self-reported questionnaire, while existing oral conditions were recorded following clinical examination using Visible Plaque Index (VPI) and Gingival Bleeding Index (GBI). Data analysis was carried out using SPSS on results obtained from the questionnaire as well as clinical examination. Results: A total of 147 subjects participated in this research project, of which 72% (103/147) were female while 28% (44/147) were male. Male subjects had statistically significantly higher mean VPI scores compared to female subjects interproximally, buccally and lingually (t-test, p<0.05). Furthermore, there exists a statistically significant negative correlation between oral health knowledge score (mean = 9.3, SD = 3.1) and VPI score (Pearson correlation test, p=0.025). Subjects who agreed accumulation of plaque or bacteria as a contributing factor to caries and periodontal diseases are statistically significantly lower than subjects who disagreed this statement in terms of mean VPI scores (53% vs 63%, t-test, p<0.05). Conclusion: Participants with better oral health knowledge who also recognized accumulation of plaque or bacteria as one of the contributing factors to dental caries and periodontal disease had better oral hygiene levels in terms of VPI.published_or_final_versio

    ZYZ-168 alleviates cardiac fibrosis after myocardial infarction through inhibition of ERK1/2-dependent ROCK1 activation

    Get PDF
    Selective treatments for myocardial infarction (MI) induced cardiac fibrosis are lacking. In this study, we focus on the therapeutic potential of a synthetic cardio-protective agent named ZYZ-168 towards MI-induced cardiac fibrosis and try to reveal the underlying mechanism. ZYZ-168 was administered to rats with coronary artery ligation over a period of six weeks. Ecocardiography and Masson staining showed that ZYZ-168 substantially improved cardiac function and reduced interstitial fibrosis. The expression of α–smooth muscle actin (α-SMA) and Collagen I were reduced as was the activity of matrix metalloproteinase 9 (MMP-9). These were related with decreased phosphorylation of ERK1/2 and expression of Rho-associated coiled-coil containing protein kinase 1 (ROCK1). In cardiac fibroblasts stimulated with TGF-β1, phenotypic switches of cardiac fibroblasts to myofibroblasts were observed. Inhibition of ERK1/2 phosphorylation or knockdown of ROCK1 expectedly reduced TGF-β1 induced fibrotic responses. ZYZ-168 appeared to inhibit the fibrotic responses in a concentration dependent manner, in part via a decrease in ROCK 1 expression through inhibition of the phosphorylation status of ERK1/2. For inhibition of ERK1/2 phosphorylation with a specific inhibitor reduced the activation of ROCK1. Considering its anti-apoptosis activity in MI, ZYZ-168 may be a potential drug candidate for treatment of MI-induced cardiac fibrosis

    Upper extremity impairments in women with or without lymphedema following breast cancer treatment

    Get PDF
    Breast-cancer-related lymphedema affects ∼25% of breast cancer (BC) survivors and may impact use of the upper limb during activity. The purpose of this study is to compare upper extremity (UE) impairment and activity between women with and without lymphedema after BC treatment. 144 women post BC treatment completed demographic, symptom, and Disability of Arm-Shoulder-Hand (DASH) questionnaires. Objective measures included Purdue pegboard, finger-tapper, Semmes-Weinstein monofilaments, vibration perception threshold, strength, range of motion (ROM), and volume. Women with lymphedema had more lymph nodes removed (p &lt; .001), more UE symptoms (p &lt; .001), higher BMI (p = .041), and higher DASH scores (greater limitation) (p &lt; .001). For all participants there was less strength (elbow flexion, wrist flexion, grip), less shoulder ROM, and decreased sensation at the medial upper arm (p &lt; .05) in the affected UE. These differences were greater in women with lymphedema, particularly in shoulder abduction ROM (p &lt; .05). Women with lymphedema had bilaterally less elbow flexion strength and shoulder ROM (p &lt; .05). Past diagnosis of lymphedema, grip strength, shoulder abduction ROM, and number of comorbidities contributed to the variance in DASH scores (R 2 of 0.463, p &lt; .001). UE impairments are found in women following treatment for BC. Women with lymphedema have greater UE impairment and limitation in activities than women without. Many of these impairments are amenable to prevention measures or treatment, so early detection by health care providers is essential

    Normal values of regional left ventricular endocardial motion: multicenter color kinesis study. Am J Physiol Heart Circ Physiol 279: H2464– H2476

    Get PDF
    . Normal values of regional left ventricular endocardial motion: multicenter color kinesis study. Am J Physiol Heart Circ Physiol 279: H2464-H2476, 2000.-Our goal was to establish normal values for quantitative color kinesis indexes of left ventricular (LV) wall motion over a wide range of ages, which are required for objective diagnosis of regional systolic and diastolic dysfunction. Color-encoded images were obtained in 194 normal subjects (95 males, 99 females, age 2 mo to 79 yr) in four standard views. Quantitative indexes of magnitude and timing of systolic and diastolic function were studied for age-and genderrelated differences. Normal limits of all ejection and filling indexes were in a narrow range (Õ…25% of the mean), with no major gender-related differences. Despite invariable ejection fractions, both peak filling and ejection rates decreased with age (30 and 20%, correspondingly) with a concomitant increase in mean filling and ejection times, resulting in fiveand twofold increases in the late to early filling and ejection ratios, correspondingly. Diastolic asynchrony increased with age (from 4.7 Ï® 2.0 to 6.4 Ï® 3.2 from the 2nd to 7th decade). The normal values of color kinesis indexes should allow objective detection of regional LV systolic and diastolic dysfunction. echocardiography; ultrasound imaging; ventricular function; wall motion COLOR KINESIS IS AN EMERGING echocardiographic technique based on acoustic quantification, which uses color-encoding to depict left ventricular (LV) systolic and diastolic endocardial motion However, a new technique, which detects abnormalities by comparing individual patient&apos;s data with normal values, relies on having these normal values established in a large sample of the normal population. Accordingly, normal values of different indexes of magnitude and timing of global and regional LV function derived from color kinesis images need to be established to allow objective detection of abnormalities with a high level of confidence. We also hypothesized that these indexes may be age and gender dependent, in which case normal values would need to be established for different demographic groups. Accordingly, the purpose of this collaborative multicenter effort was to establish normal values for magnitude and timing indexes of wall motion by acquiring and analyzing systolic and diastolic color kinesis images in a large group of normal subjects of both sexes over a wide range of ages. METHODS Study population. The protocol for this study was approved by the Institutional Review Board of the University of Chicago (protocol #9171). This protocol was initially designed to include eight age groups (8 decades between 0 and 80 yr) with a minimum of 20 normal subjects each (50% males and 50% Address for reprint requests and othe

    Upregulation of the Wnt Co-Receptor LRP6 Promotes Hepatocarcinogenesis and Enhances Cell Invasion

    Get PDF
    Background: Activation of the Wnt/b-catenin signaling pathway plays a crucial role in hepatocellular carcinoma (HCC). Lowdensity lipoprotein (LDL) receptor-related protein-6 (LRP6) is one of the co-receptors of the Wnt/b-catenin pathway and forms a signaling complex with Wnt ligand and Frizzled receptor to activate downstream signaling. However, the role of LRP6 in hepatocarcinogenesis is unclear. In this study, we examined its expression and roles in human HCC. Methodology/Principal Findings: Using real-time quantitative RT-PCR, we found that LRP6 was frequently (45%) overexpressed in human HCCs (P = 0.003). In vitro studies showed that ectopic expression of LRP6 increased the protein level of b-catenin. Moreover, overexpression of the full-length and constitutively active LRP6, respectively, activated the WNT/b-catenin signaling pathway, as shown by the TCF/b-catenin reporter assay. With regard to the effects of LRP6 overexpression in HCC cells, stable overexpression of the constitutively active LRP6 in BEL-7402 HCC cells enhanced cell proliferation, cell migration, and invasion in vitro as well as tumorigenicity in nude mice. Conclusions/Significance: Our findings indicate that overexpression of LRP6 contributes to the hyperactivation of the Wnt

    The New Application of UHPLC-DAD-TOF/MS in Identification of Inhibitors on β-Amyloid Fibrillation From Scutellaria baicalensis

    Get PDF
    Literary evidence depicts that aggregated β-amyloid (Aβ) leads to the pathogenesis of Alzheimer’s disease (AD). Although many traditional Chinese medicines (TCMs) are effective in treating neurodegenerative diseases, there is no effective way for identifying active compounds from their complicated chemical compositions. Instead of using a traditional herbal separation method with low efficiency, we herein apply UHPLC-DAD-TOF/MS for the accurate identification of the active compounds that inhibit the fibrillation of Aβ (1-42), via an evaluation of the peak area of individual chemical components in chromatogram, after incubation with an Aβ peptide. Using the neuroprotective herbal plant Scutellaria baicalensis (SB) as a study model, the inhibitory effect on Aβ by its individual compounds, were validated using the thioflavin-T (ThT) fluorescence assay, biolayer interferometry analysis, dot immunoblotting and native gel electrophoresis after UHPLC-DAD-TOF/MS analysis. The viability of cells after Aβ (1-42) incubation was further evaluated using both the tetrazolium dye (MTT) assay and flow cytometry analysis. Thirteen major chemical components in SB were identified by UHPLC-DAD-TOF/MS after incubation with Aβ (1–42). The peak areas of two components from SB, baicalein and baicalin, were significantly reduced after incubation with Aβ (1–42), compared to compounds alone, without incubation with Aβ (1–42). Consistently, both compounds inhibited the formation of Aβ (1–42) fibrils and increased the viability of cells after Aβ (1–42) incubation. Based on the hypothesis that active chemical components have to possess binding affinity to Aβ (1–42) to inhibit its fibrillation, a new application using UHPLC-DAD-TOF/MS for accurate identification of inhibitors from herbal plants on Aβ (1–42) fibrillation was developed
    • …
    corecore