2,136 research outputs found

    CSR committee and firm value during the COVID-19 pandemic

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    This paper investigates whether the presence of CSR committees has a mitigating effect on firm value (measured by Tobin's Q) during the COVID-19 pandemic. Analyzing UK listed firm data, we find that although the pandemic results in lower firm value, the presence of CSR committees helps to mitigate the negative impact of COVID-19 on firm value. The results suggest that the formation of CSR committees is not a symbolic impression management tool but an effective sustainability governance mechanism during the crisis. Our results should be helpful for regulators and companies in making decisions related to CSR committees

    EFFECTS OF FUNCTIONAL KNEE BRACES ON NEUROMUSCULAR ADAPTATION IN ANTERIOR CRUCIATE LIGAMENT INJURED PATIENTS

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    INTRODUCTION: Neuromuscular adaptation in the lower extremity has been found in anterior cruciate ligament (ACL) injured patients, with mechanical and electromyographic alterations such as reduced knee extensor moment and power, increased hamsrings muscle activity, and decreased muscle strength (Berchuck, Andriacchi, Bach, & Reider, 1990; DeVita, Lassiter, Hortobagyi, & Torry, 1998). Functional knee bracing has been a common method to enhance functional knee stability in these patients for the past three decades. However, the long-term effects of knee bracing on ACL-reconstructed (ACL-R) patients have not been reported in the literature. There is thus an urgent need to identify the effects of bracing on the gait displayed by these patients

    Apoptosis Induction in Primary Human Colorectal Cancer Cell Lines and Retarded Tumor Growth in SCID Mice by Sulforaphane

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    We have investigated the anticancer effects of the dietary isothiocyanate sulforaphane (SFN) on colorectal cancer (CRC), using primary cancer cells lines isolated from five Taiwanese colorectal cancer patients as the model for colorectal cancer. SFN-treated cells accumulated in metaphase (SFN 6.25 μM) and subG1 (SFN 12.5 and 25 μM) as determined by flow cytometry. In addition, treated cells showed nuclear apoptotic morphology that coincided with an activation of caspase-3, and loss of mitochondrial membrane potential (ΔΨm). Incubations at higher SFN doses (12.5 and 25 μM) resulted in cleavage of procaspase-3 and elevated caspase-2, -3, -8, and -9 activity, suggesting that the induction of apoptosis and the sulforaphane-induced mitosis delay at the lower dose are independently regulated. Daily SFN s.c. injections (400 micromol/kg/d for 3 weeks) in severe combined immunodeficient mice with primary human CRC (CP1 to CP5) s.c. tumors resulted in a decrease of mean tumor weight by 70% compared with vehicle-treated controls. Our findings suggest that, in addition to the known effects on cancer prevention, sulforaphane may have antitumor activity in established colorectal cancer

    High-throughput Automated Muropeptide Analysis (HAMA) Reveals Peptidoglycan Composition of Gut Microbial Cell Walls

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    Peptidoglycan (PGN), a net-like polymer constituted by muropeptides, provides protection for microorganisms and has been a major target for antibiotics for decades. Researchers have explored host-microbiome interactions through PGN recognition systems and discovered key muropeptides modulating host responses. However, most common characterization techniques for muropeptides are labor-intensive and require manual analysis of mass spectra due to the complex cross-linked PGN structures. Each species has unique moiety modifications and inter-/intra-bridges, which further complicates the structural analysis of PGN. Here, we developed a high-throughput automated muropeptide analysis (HAMA) platform leveraging tandem mass spectrometry and in silico muropeptide MS/MS fragmentation matching to comprehensively identify muropeptide structures, quantify their abundance, and infer PGN cross-linking types. We demonstrated the effectiveness of HAMA platform using well-characterized PGNs from E. coli and S. aureus and further applied it to common gut bacteria including Bifidobacterium, Bacteroides, Lactobacillus, Enterococcus, and Akkermansia muciiniphila. Specifically, we found that the stiffness and strength of the cell envelopes may correspond to the lengths and compositions of interpeptide bridges within Bifidobacterium species. In summary, the HAMA framework exhibits an automated, intuitive, and accurate analysis of PGN compositions, which may serve as a potential tool to investigate the post-synthetic modifications of saccharides, the variation in interpeptide bridges, and the types of cross-linking within bacterial PGNs.</p

    Asiatic acid, a triterpene, induces apoptosis and cell cycle arrest through activation of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase pathways in human breast cancer cells

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    ABSTRACT This study first investigates the anticancer effect of asiatic acid in two human breast cancer cell lines, MCF-7 and MDA-MB-231. Asiatic acid exhibited effective cell growth inhibition by inducing cancer cells to undergo S-G2/M phase arrest and apoptosis. Blockade of cell cycle was associated with increased p21/ WAF1 levels and reduced amounts of cyclinB1, cyclinA, Cdc2, and Cdc25C in a p53-independent manner. Asiatic acid also reduced Cdc2 function by increasing the association of p21/WAF1/Cdc2 complex and the level of inactivated phospho-Cdc2 and phospho-Cdc25C. Asiatic acid treatment triggered the mitochondrial apoptotic pathway indicated by changing Bax/Bcl-2 ratios, cytochrome c release, and caspase-9 activation, but it did not act on Fas/Fas ligand pathways and the activation of caspase-8. We also found that mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinase (ERK1/2), and p38, but not c-Jun NH 2 -terminal kinase (JNK), are critical mediators in asiatic acid-induced cell growth inhibition. U0126 [1,4-diamino-2,3-dicyano-1,4-bis(2-aminophenylthio)butadiene] or SB203580 [4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)-1H-imidazole], specific inhibitors of mitogen-activated protein kinase kinase and p38 kinase activities, significantly decreased or delayed apoptosis. Asiatic acid was likely to confine the breast cancer cells in the S-G2/M phase mainly through the p38 pathway, because both SB203580 and p38 small interfering RNA (siRNA) inhibition significantly attenuated the accumulation of inactive phospho-Cdc2 and phospho-Cdc25C proteins and the cell numbers of S-G2/M phase. Moreover, U0126 and ERK siRNA inhibition completely suppressed asiatic acid-induced Bcl-2 phosphorylation and Bax up-regulation, and caspase-9 activation. Together, these results imply a critical role for ERK1/2 and p38 but not JNK, p53, and Fas/Fas ligand in asiatic acid-induced S-G2/M arrest and apoptosis of human breast cancer cells

    The Non-linear Relationship between Muscle Voluntary Activation Level and Voluntary Force Measured by the Interpolated Twitch Technique

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    Interpolated twitch technique (ITT) is a non-invasive method for assessing the completeness of muscle activation in clinical settings. Voluntary activation level (VA), measured by ITT and estimated by a conventional linear model, was reported to have a non-linear relationship with true voluntary contraction force at higher activation levels. The relationship needs to be further clarified for the correct use by clinicians and researchers. This study was to established a modified voluntary activation (modified VA) and define a valid range by fitting a non-linear logistic growth model. Eight healthy male adults participated in this study. Each subject performed three sets of voluntary isometric ankle plantar flexions at 20, 40, 60, 80 and 100% maximal voluntary contraction (MVC) with real-time feedback on a computer screen. A supramaximal electrical stimulation was applied on tibia nerve at rest and during contractions. The estimated VA was calculated for each contraction. The relationship between the estimated VA and the actual voluntary contraction force was fitted by a logistic growth model. The result showed that according to the upper and lower limit points of the logistic curve, the valid range was between the 95.16% and 10.55% MVC. The modified VA estimated by this logistic growth model demonstrated less error than the conventional model. This study provided a transfer function for the voluntary activation level and defined the valid range which would provide useful information in clinical applications

    Interfacial Properties of Polyethylene Glycol/Vinyltriethoxysilane (PEG/VTES) Copolymers and their Application to Stain Resistance

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    In this study, polyethylene glycol (PEG) and vinyltriethoxysilane (VTES) were used in different proportions to produce a series of PEG–VTES copolymers. The copolymer molecular structures were confirmed by FTIR spectroscopy. In addition, their surface activities were evaluated by evaluating the surface tension, contact angle, and foaming properties. The results showed that these surfactants exhibited excellent surface activities and wetting power, as well as low foaming. Consequently, the application of a series of PEG/VTES copolymers can make cotton fabrics stain resistant

    Rapid detection of epidermal growth factor receptor mutations with multiplex PCR and primer extension in lung cancer

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    Epidermal growth factor receptor (EGFR) kinase domain mutations hyperactivate the kinase and confer kinase addiction of the non-small-cell lung cancer (NSCLC) tumor cells. Almost all of these mutations are located within exons 18-21. The -216 single nucleotide polymorphism in the promoter region is associated with increased EGFR production. We present a method for detecting these common mutations in 81 cases of NSCLC. The protocol is based on the multiplex amplification of promoter region and exons 18-21 of the EGFR genes in a single tube, followed by primer extension of the PCR products using various sizes of primers to detect base changes at -216 promoter region and codons 719, 746-750, 790, 858 of the EGFR gene. We compared the results with that from direct sequencing for detecting EGFR mutations in 81 cases of NSCLC. The two methods identified the same 26 mutations, but our method is superior to direct sequencing in terms of the amount of work and time required. We presented a simple and fast method to detect mutations of EGFR genes in NSCLC
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