346 research outputs found
Rapid identification of Mycobacterium tuberculosis infection by a new array format-based surface plasmon resonance method
Tubercle bacillus [TB] is one of the most important chronic infectious diseases that cause millions of deaths annually. While conventional smear microscopy and culture methods are widely used for diagnosis of TB, the former is insensitive, and the latter takes up to 6 to 8 weeks to provide a result, limiting the value of these methods in aiding diagnosis and intermediate decisions on treatment. Therefore, a rapid detection method is essential for the diagnosis, prognosis assessment, and recurrence monitoring. A new surface plasmon resonance [SPR] biosensor based on an array format, which allowed immobilizing nine TB antigens onto the sensor chip, was constructed. Simultaneous determination of multiple TB antibodies in serum had been accomplished with this array-based SPR system. The results were compared with enzyme-linked immunosorbent assay, a conventional immunological method. Array-based SPR showed more advantages in providing label-free and real-time detection. Additionally, the high sensitivity and specificity for the detection of TB infection showed its potential for future development of biosensor arrays for TB diagnosis
Metabolism and Pharmacokinetics of San-Huang-Xie-Xin-Tang, a Polyphenol-Rich Chinese Medicine Formula, in Rats and Ex-Vivo Antioxidant Activity
San-Huang-Xie-Xin-Tang (SHXXT), a widely used Chinese herbal formula, consists of rhizomes of Rheum officinale, roots of Scutellaria baicalensis and rhizomes of Coptis chinesis. This study investigated the metabolism and pharmacokinetics of polyphenols in SHXXT, including baicalin, baicalein, wogonin, emodin, aloe-emodin, rhein and chrysophanol. The quantitation methods of SHXXT decoction and rat serum using high performance liquid chromatography were developed and validated in this study. After oral administration of SHXXT decoction to rats, the parent forms of various constituents and their conjugated metabolites in serum were determined before and after hydrolysis with β-glucuronidase and sulfatase. The results showed that only free form of rhein can be quantitated, whereas the parent forms of coptisine, palmatine, berberine, baicalein, wogonin, emodin, aloe-emodin and chrysophanol were not detected in serum. The glucuronides of baicalein, wogonin, emodin, aloe-emodin, rhein and chrysophanol were the predominant forms in bloodstream. In order to evaluate the in vivo antioxidant activity of SHXXT, the serum metabolite of SHXXT was prepared, characterized and followed by evaluation of the effect on AAPH-induced hemolysis. The results indicated that metabolites of SHXXT exhibited significant free radical scavenging activity. We suggest that biologists redirect their focus to the bioactivity of the conjugated metabolites of these polyphenols
Metabolism and Pharmacokinetics of San-Huang-Xie-Xin-Tang, a Polyphenol-Rich Chinese Medicine Formula, in Rats and Ex-Vivo Antioxidant Activity
San-Huang-Xie-Xin-Tang (SHXXT), a widely used Chinese herbal formula, consists of rhizomes of Rheum officinale, roots of Scutellaria baicalensis and rhizomes of Coptis chinesis. This study investigated the metabolism and pharmacokinetics of polyphenols in SHXXT, including baicalin, baicalein, wogonin, emodin, aloe-emodin, rhein and chrysophanol. The quantitation methods of SHXXT decoction and rat serum using high performance liquid chromatography were developed and validated in this study. After oral administration of SHXXT decoction to rats, the parent forms of various constituents and their conjugated metabolites in serum were determined before and after hydrolysis with β-glucuronidase and sulfatase. The results showed that only free form of rhein can be quantitated, whereas the parent forms of coptisine, palmatine, berberine, baicalein, wogonin, emodin, aloe-emodin and chrysophanol were not detected in serum. The glucuronides of baicalein, wogonin, emodin, aloe-emodin, rhein and chrysophanol were the predominant forms in bloodstream. In order to evaluate the in vivo antioxidant activity of SHXXT, the serum metabolite of SHXXT was prepared, characterized and followed by evaluation of the effect on AAPH-induced hemolysis. The results indicated that metabolites of SHXXT exhibited significant free radical scavenging activity. We suggest that biologists redirect their focus to the bioactivity of the conjugated metabolites of these polyphenols
Discussing the conceptual framework of cultural landscape in Taiwan
This study aims to develop a measureable tool to identify the feature of
Taiwan cultural landscape. In-depth interviews from ten scholars were first
conducted to design a questionnaire which contained a seven-dimension
measurement model of identifying cultural landscape, and then 808 local
participants were asked to response this questionnaire for gathering the
quantitative data in four cultural significant sites. Exploratory factor analysis
and confirmatory factor analysis were applied to confirm the structure of the
supposed measurement model from the questionnaire data. The result of
factor analysis showed that the confirmed measurement model was less
complicated than the supposed measurement model. The cultural feature
dimension of cultural landscape was composed of three factors which are
environment element, human evidence and traditional custom. And the place
meaning dimension of cultural landscape contained cultural atmosphere, life
dependence and affective identity. This finding revealed the evidence that
local participants’ perception to the feature of cultural landscape was very
different from experts’ understanding of the composition of cultural
landscape in Taiwan. It also hints the difficulty of conservation for cultural
landscape was local people’s disregards to their cultural landscape since
these features didn’t have any physical connection with local people’s daily
life. This study build a 16-item scale measuring cultural landscape from the
perspective of local people in Taiwan, which provide practitioners a reliable
and valid analytical tool to assess cultural landscape. And it also offered
government agencies a useful foundation to make conservation strategies
with local people for cultural landscape
Effect of bis(hydroxymethyl) alkanoate curcuminoid derivative MTH-3 on cell cycle arrest, apoptotic and autophagic pathway in triple-negative breast adenocarcinoma MDA-MB-231 cells: An in vitro study
Curcumin has been shown to exert potential antitumor activity in vitro and in vivo involved in multiple signaling pathways. However, the application of curcumin is still limited because of its poor hydrophilicity and low bio-availability. In the present study, we investigated the therapeutic effects of a novel and water soluble bis(hydroxymethyl) alkanoate curcuminoid derivative, MTH-3, on human breast adenocarcinoma MDA-MB-231 cells. This study investigated the effect of MTH-3 on cell viability, cell cycle and induction of autophagy and apoptosis in MDA-MB-231 cells. After 24-h treatment with MTH-3, a concentration-dependent decrease in MDA-MB-231 cell viability was observed, and the IC50 value was 5.37±1.22 μM. MTH-3 significantly triggered G2/M phase arrest and apoptosis in MDA-MB-231 cells. Within a 24-h treatment, MTH-3 decreased the CDK1 activity by decreasing CDK1 and cyclin B1 protein levels. MTH-3-induced apoptosis was further confirmed by morphological assessment and Annexin V/PI staining assay. Induction of apoptosis caused by MTH-3 was accompanied by an apparent increase of DR3, DR5 and FADD and, as well as a marked decrease of Bcl-2 and Bcl-xL protein expression. MTH-3 also decreased the protein levels of Ero1, PDI, PERK and calnexin, as well as increased the expression of IRE1α, CHOP and Bip that consequently led to ER stress and MDA-MB-231 cell apoptosis. In addition, MTH-3-treated cells were involved in the autophagic process and cleavage of LC3B was observed. MTH-3 enhanced the protein levels of LC3B, Atg5, Atg7, Atg12, p62 and Beclin-1 in MDA-MB-231 cells. Finally, DNA microarray was carried out to investigate the level changes of gene expression modulated by MTH-3 in MDA-MB-231 cells. Taken together, our results suggest that MTH-3 might be a novel therapeutic agent for the treatment of triple-negative breast cancer in the near future
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Publisher Correction: Copper adparticle enabled selective electrosynthesis of n-propanol.
An amendment to this paper has been published and can be accessed via a link at the top of the paper
Motivations and reasons for women attending a Breast Self-Examination training program: A qualitative study
<p>Abstract</p> <p>Background</p> <p>Breast cancer is a major threat to Taiwanese women's health. Despite the controversy surrounding the effectiveness of breast self-examination (BSE) in reducing mortality, BSE is still advocated by some health departments. The aim of the study is to provide information about how women decide to practice BSE and their experiences through the training process. Sixty-six women aged 27-50 were recruited.</p> <p>Methods</p> <p>A descriptive study was conducted using small group and individual in-depth interviews to collect data, and using thematic analysis and constant comparison techniques for data analysis.</p> <p>Results</p> <p>It was found that a sense of self-security became an important motivator for entering BSE training. The satisfaction in obtaining a sense of self-security emerged as the central theme. Furthermore, a ladder motivation model was developed to explain the participants' motivations for entering BSE training. The patterns of motivation include opportunity taking, clarifying confusion, maintaining health, and illness monitoring, which were connected with the risk perception for breast cancer.</p> <p>Conclusions</p> <p>We recognize that the way women decide to attend BSE training is influenced by personal and social factors. Understanding the different risk assessments women rely on in making their health decisions is essential. This study will assist researchers and health professionals to gain a better understanding of alternative ways to deal with breast health, and not to be limited by the recommendations of the health authorities.</p
Homogeneous low-molecular-weight heparins with reversible anticoagulant activity
Low-molecular-weight heparins (LMWHs) are carbohydrate-based anticoagulants clinically used to treat thrombotic disorders, but impurities, structural heterogeneity or functional irreversibility can limit treatment options. We report a series of synthetic LMWHs prepared by cost-effective chemoenzymatic methods. The high activity of one defined synthetic LMWH against human factor Xa (FXa) was reversible in vitro and in vivo using protamine, demonstrating that synthetically accessible constructs can have a critical role in the next generation of LMWHs
WDHD1 modulates the post-transcriptional step of the centromeric silencing pathway
The centromere is a highly specialized chromosomal element that is essential for chromosome segregation during mitosis. Centromere integrity must therefore be properly preserved and is strictly dependent upon the establishment and maintenance of surrounding chromatin structure. Here we identify WDHD1, a WD40-domain and HMG-domain containing protein, as a key regulator of centromere function. We show that WDHD1 associates with centromeres in a cell cycle-dependent manner, coinciding with mid-to-late S phase. WDHD1 down-regulation compromises HP1α localization to pericentric heterochromatin and leads to altered expression of epigenetic markers associated with this chromatin region. As a consequence, such reduced epigenetic silencing is manifested in disrupted heterochromatic state of the centromere and a defective mitosis. Moreover, we demonstrate that a possible underlying mechanism of WDHD1’s involvement lies in the proper generation of the small non-coding RNAs encoded by the centromeric satellite repeats. This role is mediated at the post-transcriptional level and likely through stabilizing Dicer association with centromeric RNA. Collectively, these findings suggest that WDHD1 may be a critical component of the RNA-dependent epigenetic control mechanism that sustains centromere integrity and genomic stability
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