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INTRODUCTION: Antiviral treatment can reduce the burden of COVID-19. But utilisation can be suboptimal, even in a setting like Singapore where it is fully subsidized for those with selected medical conditions and older adults (≥ 50 years). We hence investigated the factors affecting awareness, acceptance, and initiative to request Paxlovid. METHODS: We assessed the Paxlovid awareness, factors impacting its uptake in a survey conducted from August 2022 to September 2022 through the SOCRATES cohort. Multivariable logistic regression was used to investigate associations between sociodemographics, perceptions, and attitudes with the key study outcomes. RESULTS: Among respondents to the Paxlovid survey, 54% were aware of Paxlovid. On being provided essential details about Paxlovid, 75% reported they would likely be receptive to taking it if prescribed, and 38% indicated the initiative to request for it if it was not suggested by their doctors. Factors associated with awareness of Paxlovid include aged 40 years old and above, higher education, citing websites as an information source, greater trust in healthcare providers (aOR: 1.65, 95% CI 1.26 - 2.15) and government communications (aOR: 0.69, 95% CI 0.55 - 0.86), and higher perceived risk of COVID-19 infection (aOR: 1.25, 95% CI 1.10 - 1.42). Factors associated with acceptance to take Paxlovid include male gender, citing trust in healthcare providers (aOR: 1.49, 95% CI 1.11 - 1.99) and government communications (aOR: 1.38, 95% CI 1.09 - 1.76), and higher perceived severity of COVID-19 (aOR: 1.23, 95% CI 1.07 - 1.42). Factors associated with initiative to request Paxlovid include male gender, having pre-existing diabetes and higher perceived severity of COVID-19 (aOR: 1.24, 95% CI 1.09 - 1.40). The most common reasons for why respondents might not take Paxlovid were concerns about side effects (64%), concerns about costs (29%), and the perception that COVID-19 is a mild (25%). CONCLUSION: The majority of our respondents would take Paxlovid if it was prescribed to them, but a much smaller proportion would have the initiative to request for this. Key factors that may influence uptake are COVID-19 threat perceptions, trust in healthcare and government, and perceptions of the drug's side effects and cost.
Subject(s)
Antiviral Agents , COVID-19 Drug Treatment , Ritonavir , Humans , Male , Female , Singapore/epidemiology , Adult , Middle Aged , Antiviral Agents/therapeutic use , Aged , Ritonavir/therapeutic use , Patient Acceptance of Health Care/statistics & numerical data , Patient Acceptance of Health Care/psychology , Surveys and Questionnaires , Health Knowledge, Attitudes, Practice , Young Adult , COVID-19/epidemiology , COVID-19/psychology , SARS-CoV-2ABSTRACT
At least seven dominantly inherited spinocerebellar ataxias (SCA) are caused by expansions of polyglutamine (polyQ)-encoding CAG repeat. The misfolded and aggregated polyQ-expanded proteins increase reactive oxygen species (ROS), cellular toxicity, and neuroinflammation in the disease pathogenesis. In this study, we evaluated the anti-inflammatory potentials of coumarin derivatives LM-021, LMDS-1, LMDS-2, and pharmacological chaperone tafamidis using mouse BV-2 microglia and SCA3 ataxin-3 (ATXN3)/Q75-GFP SH-SY5Y cells. The four tested compounds displayed anti-inflammatory activity by suppressing nitric oxide (NO), interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α production, and CD68 antigen (CD68) and histocompatibility-2 (MHCII) expression in lipopolysaccharides (LPS)/interferon (IFN)-γ-stimulated BV-2 microglia. In retinoic acid-differentiated ATXN3/Q75-GFP-expressing SH-SY5Y cells inflamed with LPS/IFN-γ-primed BV-2 conditioned medium, treatment with test compounds mitigated the increased caspase 1 activity and lactate dehydrogenase release, reduced ROS and ATXN3/Q75 aggregation, and promoted neurite outgrowth. Examination of IL-1ß and IL-6-mediated signaling pathways revealed that LM-021, LMDS-1, LMDS-2, and tafamidis decreased NLR family pyrin domain containing 1 (NLRP1), c-Jun N-terminal kinase/c-Jun proto-oncogene (JNK/JUN), inhibitor of kappa B (IκBα)/P65, mitogen-activated protein kinase 14/signal transducer and activator of transcription 1 (P38/STAT1), and/or Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) signaling. The study results suggest the potential of LM-021, LMDS-1, LMDS-2, and tafamidis in treating SCA3 and probable other polyQ diseases.
Subject(s)
Machado-Joseph Disease , Neuroblastoma , Animals , Humans , Mice , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Interleukin-1beta/antagonists & inhibitors , Interleukin-6 , Lipopolysaccharides/pharmacology , Machado-Joseph Disease/drug therapy , Machado-Joseph Disease/genetics , NF-kappa B/metabolism , Reactive Oxygen Species/metabolism , Signal TransductionABSTRACT
Introduction: Lactobacillus plantarum PS128 (PS128) could be considered an antioxidant supplement to reduce muscle fatigue and improve exercise capacity recovery after vigorous exercise. Purpose: The purpose of this study is to investigate the effect of PS128 on muscle fatigue and electromyography (EMG) activity after a half-marathon (HM). Methods: The experimental design used a repeated-measures design with a double-blind approach. The participants either took two capsules of PS128 for 4 weeks as the PS128 group (PSG, n = 8) or took two capsules of a placebo for 4 weeks as the placebo group (PLG, n = 8) to ensure counterbalancing. The time points of the maximal voluntary isometric contraction (MVIC) and EMG activity test were set before probiotics were taken (baseline), 48 h before HM (Pre), and immediately at 0 h, 3 h, 24 h, 48 h, 72 h, and 96 h after HM. Results: EMG activity included median power frequency (MDF), integrated EMG (iEMG), and neuromuscular efficiency (peak torque/iEMG). The MVICs of knee extensors, analyzed by using an isokinetic dynamometer, showed a decrease from the Pre to 0 h (p = 0.0001), 3 h (p < 0.0001), 24 h (p < 0.0001), 48 h (p < 0.0001), 72 h (p = 0.0002), and 96 h (p = 0.0408) time points in the PLG. Sidak's multiple comparisons tests showed that the PLG was significantly lower than the PSG at 0 h (p = 0.0173), 3 h (p < 0.0001), 24 h (p < 0.0001), 48 h (p < 0.0001), 72 h (p < 0.0001), and 96 h (p = 0.0004) time points. The MDF of vastus medialis oblique (VMO) in the PLG was significantly decreased 24 h after HM and significantly lower than that in the PSG at all times points after HM. The iEMG of VMO in the PLG was significantly decreased 48 h after HM and significantly lower than that in the PSG at 0 h, 3 h, 24 h, 48 h, and 72 h after HM. Conclusion: The PS128 supplementation may prevent the decrease in MDF, iEMG, and peak torque after vigorous exercise. Recreational runners may consider implementing a probiotic supplementation regimen as a potential strategy to mitigate muscle fatigue following HM.
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Rowing competitions require consistent rowing strokes among crew members to achieve optimal performance. However, existing motion analysis techniques often rely on wearable sensors, leading to challenges in sporter inconvenience. The aim of our work is to use a graph-matching network to analyze the similarity in rowers' rowing posture and further pair rowers to improve the performance of their rowing team. This study proposed a novel video-based performance analysis system to analyze paired rowers using a graph-matching network. The proposed system first detected human joint points, as acquired from the OpenPose system, and then the graph embedding model and graph-matching network model were applied to analyze similarities in rowing postures between paired rowers. When analyzing the postures of the paired rowers, the proposed system detected the same starting point of their rowing postures to achieve more accurate pairing results. Finally, variations in the similarities were displayed using the proposed time-period similarity processing. The experimental results show that the proposed time-period similarity processing of the 2D graph-embedding model (GEM) had the best pairing results.
ABSTRACT
BACKGROUND/AIM: The aim of this study was to evaluate the influence of chitosan on the growth of nasal septal chondrocytes (NSCs). The final goal was to establish a novel methodology to enhance nasal septal cartilage regeneration. MATERIALS AND METHODS: Human NSCs were isolated and their morphology was examined using Alcian blue staining and observed by light microscopy. The isolated NSCs were grown with various concentrations of chitosan and the expression of COL2A1 was investigated. RESULTS: NSCs were successfully isolated from nasal septal cartilage. Co-culture with 0.2% of chitosan greatly enhanced proliferation of NSCs compared to control cells. However, 0.5% of chitosan was harmful to NSCs, resulting in cell detachment from the culture plate. Furthermore, the addition of 0.2% chitosan significantly improved the expression of COL2A1 in NSCs. CONCLUSION: To our knowledge, this is the first report to demonstrate that chitosan could effectively guide the attachment and growth of human NSCs. Chitosan appears to be a promising additive for NSC culture, which sets the stage for studying tissue regeneration in nasal septal cartilage deficiency, rhinoplasty, and craniofacial reconstruction.
Subject(s)
Chitosan , Chondrocytes , Humans , Chitosan/pharmacology , Cells, Cultured , Tissue Engineering/methods , Cartilage , Tissue ScaffoldsABSTRACT
Peri-implantitis is a common complication characterized by inflammation in tissues surrounding dental implants due to plaque accumulation, which can lead to implant failure. While air flow abrasive treatment has been found to be effective for debriding implant surfaces, little is known about the factors that affect its cleaning capacity. This study systematically examined the cleaning capacity of air powder abrasive (APA) treatment with ß-tricalcium phosphate (ß-TCP) powder, using various powder jetting strengths and different particle sizes. Three sizes of ß-TCP powder (S, M, and L) were prepared, and different powder settings (low, medium, and high) were tested. The cleaning capacity was determined by quantifying ink removal, which simulated biofilm removal from the implant surfaces at different time points. The results of the systematic comparisons showed that the most efficient cleaning of implant surfaces was achieved using size M particles with medium setting. Additionally, the amount of powder consumed was found to be critical to cleaning efficiency, and the implant surfaces were altered in all tested groups. These systematically analyzed outcomes may provide insights into the development of potential non-surgical strategies for treating peri-implant diseases.
Subject(s)
Dental Implants , Peri-Implantitis , Humans , Powders , Debridement , Surface Properties , Peri-Implantitis/therapyABSTRACT
BACKGROUND/AIM: Surface biomarkers, such as CD44 and CD133, have been demonstrated to be expressed in prostate cancer cells, and our previous study has shown that prostate cancer cell lines could be divided into three groups according to the single and combined expression pattern of CD44 and 133. In order to refine prognostication in prostate cancer cells, we further investigated genetic biomarkers, prostate cancer antigen 3 (PCA3), kallikrein 4 (KLK4), and KLK9 in different prostate cancer cell lines. MATERIALS AND METHODS: CWR22Rv1, PC3, and DU145 cell lines were cultured until 95% confluence. The single expression of CD44 or CD133 and their combined expression were analyzed by flow cytometry, and gene expression of b-actin, PCA3, KLK4, and KLK9 was analyzed by real-time polymerase chain reaction. RESULTS: The single expression of CD133 was less than 4% in all cell lines examined. PC3 and DU145 cells displayed a high expression of CD44 (>91%), whereas CWR22Rv1 was the only cell line that demonstrated a high co-expression of both CD44 and CD133 (>91%). In addition, PC3 and DU145 displayed low expression of PCA3, KLK4, and KLK9 when compared with their own b-actin expression. In contrast, CWR22Rva showed high expression of PCA3 and KLK4 although KLK9 expression was also low. CONCLUSION: Both surface and genetic biomarkers should be validated for a more accurate prognosis in prostate cancer.
Subject(s)
Actins , Prostatic Neoplasms , Male , Humans , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Prostatic Neoplasms/genetics , Prostatic Neoplasms/metabolism , Cell Line , ProstateABSTRACT
Poloxamers are negatively temperature-sensitive hydrogels and their hydrophilic groups interact with water molecules at lower temperatures (liquid phase) while their hydrophobic groups interact more strongly with increases in temperature causing gelation. To investigate the factors affecting the rheological properties of poloxamers, various parameters including different poloxamer P407 concentrations, poloxamers P407/P188 blending ratios and additives were examined. The results presented a clear trend of decreasing gelling temperature/time when P407 was at higher concentrations. Moreover, the addition of P188 enhanced the gelling temperature regardless of poloxamer concentration. Polysaccharides and their derivatives have been widely used as components of hydrogel and we found that alginic acid (AA) or carboxymethyl cellulose (CMC) reduced the gelling temperature of poloxamers. In addition, AA-containing poloxamer promoted cell proliferation and both AA -and CMC-containing poloxamer hydrogels reduced cell migration. This study investigated the intriguing characteristics of poloxamer-based hydrogel, providing useful information to compounding an ideal and desired thermo-sensitive hydrogel for further potential clinical applications such as development of sprayable anti-adhesive barrier, wound-healing dressings or injectable drug-delivery system for cartilage repair.
ABSTRACT
Decellularized matrices can effectively reduce severe immune rejection with their cells and eliminated nucleic acid material and provide specific environments for tissue repair or tissue regeneration. In this study, we prepared acellular cartilage matrix (ACM) powder through the decellularization method and developed ACM hydrogels by physical, chemical, and enzymatic digestion methods. The results demonstrated that the small size group of ACM hydrogels exhibited better gel conditions when the concentration of ACM hydrogels was 30 and 20 mg/mL in 1N HCl through parameter adjustment. The data also confirmed that the ACM hydrogels retained the main components of cartilage: 61.18% of glycosaminoglycan (GAG) and 78.29% of collagen, with 99.61% of its DNA removed compared to samples without the decellularization procedure (set as 100%). Through turbidimetric gelation kinetics, hydrogel rheological property analysis, and hydrogel tissue physical property testing, this study also revealed that increasing hydrogel concentration is helpful for gelation. Besides, the ex vivo test confirmed that a higher concentration of ACM hydrogels had good adhesive properties and could fill in cartilage defects adequately. This study offers useful information for developing and manufacturing ACM hydrogels to serve as potential alternative scaffolds for future cartilage defect treatment.
ABSTRACT
The demand of bone grafting is increasing as the population ages worldwide. Although bone graft materials have been extensively developed over the decades, only a few injectable bone grafts are clinically available and none of them can be extruded from 18G needles. To overcome the existing treatment limitations, the aim of this study is to develop ideal injectable implants from biomaterials for minimally invasive surgery. An injectable composite bone graft containing calcium sulfate hemihydrate, tetracalcium phosphate, and anhydrous calcium hydrogen phosphate (CSH/CaP paste) was prepared with different CSH/CaP ratios and different concentrations of additives. The setting time, injectability, mechanical properties, and biocompatibility were evaluated. The developed injectable CSH/CaP paste (CSH/CaP 1:1 supplemented with 6% citric acid and 2% HPMC) presented good handling properties, great biocompatibility, and adequate mechanical strength. Furthermore, the paste was demonstrated to be extruded from a syringe equipped with 18G needles and exerted a great potential for minimally invasive surgery. The developed injectable implants with tissue repairing potentials will provide an ideal therapeutic strategy for minimally invasive surgery to apply in the treatment of maxillofacial defects, certain indications in the spine, inferior turbinate for empty nose syndrome (ENS), or reconstructive rhinoplasty.
Subject(s)
Calcium Phosphates , Calcium Sulfate , Biocompatible Materials/pharmacology , Bone Cements/pharmacology , Bone and Bones , Calcium Phosphates/pharmacology , Calcium Sulfate/pharmacology , Minimally Invasive Surgical ProceduresABSTRACT
Using barbed thread lifting for facial rejuvenation has become popular these days due to its minimally invasive procedures with reduced complications. However, only limited studies regarding its mechanical properties for face suspension were published. The aim of this study was to evaluate suture-holding ability regarding its facelift property, and different specimens were tested in order to establish an in vitro model. Fresh porcine tissue and the synthetic material polydimethylsiloxane (PDMS) were selected to simulate human skin for evaluating barbed suture pull-out strength by the universal material testing machine. The results showed that the pull-out strength of barbs between different porcine tissues varied without consistency. By contrast, PDMS (30:1) showed more consistent pull-out strength in each testing, and the average maximum load force was close to porcine tissue. Furthermore, after submerging barbed sutures in PBS for 0 days (T0), 7 days (T7) and 14 days (T14), a trend of decreased average maximum load force, displacement and force of 1.5 mm/2 mm/3 mm displacement could be detected by in vitro testing with PDMS (30:1). These results provide support for using PDMS (30:1) to evaluate suture pull-out strength and holding/lifting capacities in vitro to obtain consistent and objective information for evaluating substantial equivalence of devices. The established in vitro method could be used for the future development of barbed thread lifting technology.
ABSTRACT
Demineralized bone matrix (DBM) is a decalcified allo/xenograft retaining collagen and noncollagenous proteins, which has been extensively used because of its osteoconductive and osteoinductive properties. Calcium sulfate (CaSO4, CS) is a synthetic bone substitute used in bone healing with biocompatible, nontoxic, bioabsorbable, osteoconductive, and good mechanical characteristics. This study aims to prepare a DBM/CS composite bone graft material in a moldable putty form without compromising the peculiar properties of DBM and CS. For this purpose, firstly, porcine femur was defatted using chloroform/methanol and extracted by acid for demineralization, then freeze-dried and milled/sieved to obtain DBM powder. Secondly, the α-form and ß-form of calcium sulfate hemihydrate (CaSO4·0.5H2O, CSH) were produced by heating gypsum (CaSO4·2H2O). The morphology and particle sizes of α- and ß-CSH were obtained by SEM, and their chemical properties were confirmed by EDS, FTIR and XRD. Furthermore, the DBM-based graft was mixed with α- or ß-CSH at a ratio of 9:1, and glycerol/4% HPMC was added as a carrier to produce a putty. DBM/CSH putty possesses a low washout rate, good mechanical strength and biocompatibility. In conclusion, we believe that the moldable DBM/CSH composite putty developed in this study could be a promising substitute for the currently available bone grafts, and might have practical application in the orthopedics field as a potential bone void filler.
ABSTRACT
Periprosthetic joint infection (PJI) is a devastating complication after total joint replacement with considerable morbidity and large economic burdens. Antibiotic-Loaded Bone Cement (ALBC) has been developed as a valuable tool for local administration and is becoming one of the most effective methods for the prevention and treatment of orthopedic infections. Controlling antibiotic release from ALBC is critical to achieve effective infection control, however, the antibiotic elution rates are generally low, and the mechanisms are poorly understood. Thus, the present study aims to investigate the effects of the basic acrylic bone cement components, including liquid/powder (monomer-to-polymer) ratios, radiopacifier, initiator, and doses of antibiotics on the porosity, antibiotic elution rates and mechanical properties of polymethylmethacrylate (PMMA) based ALBC. The obtained results from the in vitro studies suggested that a reduction in the liquid/powder ratio and an increase in the radiopacifier ratio and gentamicin doses led to increased porosity and release of antibiotic, while the initiator ratio exerted no effect on elution rates. In conclusion, we hope that by varying the composition of ALBC, we could considerably enhance the antibiotic elution rates by increasing porosity, while maintaining an adequate mechanical strength of the bone cements. This finding might provide insights into controlling antibiotic release from ALBC to achieve effective infection control after total joint replacement surgery.
ABSTRACT
Spinocerebellar ataxia type 3 (SCA3) is an autosomal dominant neurodegenerative disorder caused by a CAG repeat expansion within the ATXN3/MJD1 gene. The expanded CAG repeats encode a polyglutamine (polyQ) tract at the C-terminus of the ATXN3 protein. ATXN3 containing expanded polyQ forms aggregates, leading to subsequent cellular dysfunctions including an impaired ubiquitin-proteasome system (UPS). To investigate the pathogenesis of SCA3 and develop potential therapeutic strategies, we established induced pluripotent stem cell (iPSC) lines from SCA3 patients (SCA3-iPSC). Neurons derived from SCA3-iPSCs formed aggregates that are positive to the polyQ marker 1C2. Treatment with the proteasome inhibitor, MG132, on SCA3-iPSC-derived neurons downregulated proteasome activity, increased production of radical oxygen species (ROS), and upregulated the cleaved caspase 3 level and caspase 3 activity. This increased susceptibility to the proteasome inhibitor can be rescued by a Chinese herbal medicine (CHM) extract NH037 (from Pueraria lobata) and its constituent daidzein via upregulating proteasome activity and reducing protein ubiquitination, oxidative stress, cleaved caspase 3 level, and caspase 3 activity. Our results successfully recapitulate the key phenotypes of the neurons derived from SCA3 patients, as well as indicate the potential of NH037 and daidzein in the treatment for SCA3 patients.
Subject(s)
Induced Pluripotent Stem Cells/pathology , Isoflavones/pharmacology , Machado-Joseph Disease/pathology , Neurons/pathology , Proteasome Endopeptidase Complex/metabolism , Pueraria/chemistry , Ubiquitin/metabolism , Adult , Aged , Animals , Caspase 3/metabolism , Cell Death/drug effects , Cell Differentiation/drug effects , Female , Humans , Induced Pluripotent Stem Cells/drug effects , Leupeptins/pharmacology , Male , Mice , Middle Aged , Neurons/drug effects , Oxidative Stress/drug effects , Peptides/metabolism , Proteasome Inhibitors/pharmacology , Protein Aggregates/drug effectsABSTRACT
Spinocerebellar ataxia (SCA) type 17 is an autosomal dominant ataxia caused by expanded polyglutamine (polyQ) tract in the TATA-box binding protein (TBP). Substantial studies have shown involvement of compromised mitochondria biogenesis regulator peroxisome proliferator-activated receptor gamma-coactivator 1 alpha (PGC-1α), nuclear factor erythroid 2-related factor 2 (NRF2), nuclear factor-Y subunit A (NFYA), and their downstream target genes in the pathogenesis of polyQ-expansion diseases. The extracts of Paeonia lactiflora (P. lactiflora) and Glycyrrhiza uralensis (G. uralensis) have long been used as a Chinese herbal medicine (CHM). Shaoyao Gancao Tang (SG-Tang) is a formulated CHM made of P. lactiflora and G. uralensis at a 1:1 ratio. In the present study, we demonstrated the aggregate-inhibitory and anti-oxidative effect of SG-Tang in 293 TBP/Q79 cells. We then showed that SG-Tang reduced the aggregates and ameliorated the neurite outgrowth deficits in TBP/Q79 SH-SY5Y cells. SG-Tang upregulated expression levels of NFYA, PGC-1α, NRF2, and their downstream target genes in TBP/Q79 SH-SY5Y cells. Knock down of NFYA, PGC-1α, and NRF2 attenuated the neurite outgrowth promoting effect of SG-Tang on TBP/Q79 SH-SY5Y cells. Furthermore, SG-Tang inhibited aggregation and rescued motor-deficits in SCA17 mouse model. The study results suggest the potential of SG-Tang in treating SCA17 and probable other polyQ diseases.
Subject(s)
Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Spinocerebellar Ataxias/drug therapy , Animals , CCAAT-Binding Factor/genetics , CCAAT-Binding Factor/metabolism , Cell Line , Drug Evaluation, Preclinical , Gene Knockdown Techniques , Glycyrrhiza uralensis , Humans , Mice, Transgenic , Molecular Targeted Therapy , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Neuronal Outgrowth/drug effects , Oxidative Stress/drug effects , Paeonia , Peptides/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Phytotherapy , Spinocerebellar Ataxias/metabolism , TATA-Box Binding Protein/drug effects , TATA-Box Binding Protein/metabolismABSTRACT
BACKGROUND: Few studies have evaluated the relative cross-protection conferred by infection with different groups of viruses through studies of sequential infections in humans. We investigated the presence of short-lived relative cross-protection conferred by specific prior viral infections against subsequent febrile respiratory illness (FRI). METHODS: Men enlisted in basic military training between December 2009 and December 2014 were recruited, with the first FRI as the study entry point. ResPlex II assays and real-time polymerase chain reaction assays were used to detect viral pathogens in nasal wash samples, and survival analyses were performed to determine whether infection with particular viruses conferred short-lived relative cross-protection against FRI. RESULTS: Prior infection with adenovirus (hazard ratio [HR], 0.24; 95% confidence interval [CI], .14-.44) or influenza virus (HR, 0.52; 95% CI, .38-.73) conferred relative protection against subsequent FRI episode. Results were statistically significant even after adjustment for the interval between enlistment and FRI (P < .001). Adenovirus-positive participants with FRI episodes tended to be protected against subsequent infection with adenovirus, coronavirus, enterovirus/rhinovirus, and influenza virus (P = .062-.093), while men with influenza virus-positive FRI episodes tended be protected against subsequent infection with adenovirus (P = .044) and influenza virus (P = .081). CONCLUSION: Prior adenovirus or influenza virus infection conferred cross-protection against subsequent FRI episodes relative to prior infection due to other circulating viruses.
Subject(s)
Cross Protection/immunology , Respiratory Tract Infections/immunology , Virus Diseases/immunology , Viruses/immunology , Female , Humans , Male , Military Personnel , Respiratory Tract Infections/virology , Singapore , Survival Analysis , Virus Diseases/virologyABSTRACT
Nine autosomal dominant spinocerebellar ataxias (SCAs) are caused by an abnormal expansion of CAG trinucleotide repeats that encodes a polyglutamine (polyQ) tract within different genes. Accumulation of aggregated mutant proteins is a common feature of polyQ diseases, leading to progressive neuronal dysfunction and degeneration. SCA type 3 (SCA3), the most common form of SCA worldwide, is characterized by a CAG triplet expansion in chromosome 14q32.1 ATXN3 gene. As accumulation of the mutated polyQ protein is a possible initial event in the pathogenic cascade, clearance of aggregated protein by ubiquitin proteasome system (UPS) has been proposed to inhibit downstream detrimental events and suppress neuronal cell death. In this study, Chinese herbal medicine (CHM) extracts were studied for their proteasome-activating, polyQ aggregation-inhibitory and neuroprotective effects in GFPu and ATXN3/Q 75 -GFP 293/SH-SY5Y cells. Among the 14 tested extracts, 8 displayed increased proteasome activity, which was confirmed by 20S proteasome activity assay and analysis of ubiquitinated and fused GFP proteins in GFPu cells. All the eight extracts displayed good aggregation-inhibitory potential when tested in ATXN3/Q 75 -GFP 293 cells. Among them, neuroprotective effects of five selected extracts were shown by analyses of polyQ aggregation, neurite outgrowth, caspase 3 and proteasome activities, and ATXN3-GFP, ubiquitin, BCL2 and BAX protein levels in neuronal differentiated ATXN3/Q 75 -GFP SH-SY5Y cells. Finally, enhanced proteasome function, anti-oxidative activity and neuroprotection of catalpol, puerarin and daidzein (active constituents of Rehmannia glutinosa and Pueraria lobata) were demonstrated in GFPu and/or ATXN3/Q 75 -GFP 293/SH-SY5Y cells. This study may have therapeutic implication in polyQ-mediated disorders.
Subject(s)
Antioxidants , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Machado-Joseph Disease/drug therapy , Machado-Joseph Disease/genetics , Neuroprotective Agents , Peptides/genetics , Peptides/metabolism , Phytotherapy , Proteasome Endopeptidase Complex/metabolism , Protein Aggregation, Pathological/metabolism , Ubiquitin/metabolism , Cells, Cultured , HEK293 Cells , Humans , Iridoid Glucosides/pharmacology , Iridoid Glucosides/therapeutic use , Isoflavones/pharmacology , Isoflavones/therapeutic use , Molecular Targeted Therapy , Mutation , Protein Aggregation, Pathological/prevention & control , Pueraria/chemistry , Rehmannia/chemistry , Trinucleotide Repeat Expansion/geneticsABSTRACT
Misfolded tau proteins induce accumulation of free radicals and promote neuroinflammation by activating microglia-releasing proinflammatory cytokines, leading to neuronal cell death. Traditional Chinese herbal medicines (CHMs) have been widely used in clinical practice to treat neurodegenerative diseases associated with oxidative stress and neuroinflammation. This study examined the neuroprotection effects of formulated CHMs Bai-Shao (made of Paeonia lactiflora), Gan-Cao (made of Glycyrrhiza uralensis), and Shaoyao Gancao Tang (SG-Tang, made of P. lactiflora and G. uralensis at 1 : 1 ratio) in cell model of tauopathy. Our results showed that SG-Tang displayed a greater antioxidative and antiaggregation effect than Bai-Shao and Gan-Cao and a stronger anti-inflammatory activity than Bai-Shao but similar to Gan-Cao. In inducible 293/SH-SY5Y cells expressing proaggregant human tau repeat domain (ΔK280 tauRD), SG-Tang reduced tau misfolding and reactive oxygen species (ROS) level in ΔK280 tauRD 293 cells and promoted neurite outgrowth in ΔK280 tauRD SH-SY5Y cells. Furthermore, SG-Tang displayed anti-inflammatory effects by reducing nitric oxide (NO) production in mouse BV-2 microglia and increased cell viability of ΔK280 tauRD-expressing SH-SY5Y cells inflamed by BV-2 conditioned medium. To uncover the neuroprotective mechanisms of SG-Tang, apoptosis protein array analysis of inflamed tau expressing SH-SY5Y cells was conducted and the suppression of proapoptotic proteins was confirmed. In conclusion, SG-Tang displays neuroprotection by exerting antioxidative and anti-inflammatory activities to suppress neuronal apoptosis in human tau cell models. The study results lay the base for future applications of SG-Tang on tau animal models to validate its effect of reducing tau misfolding and potential disease modification.
Subject(s)
Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Drug Compounding , Drugs, Chinese Herbal/pharmacology , Neurons/drug effects , Neuroprotective Agents/pharmacology , Tauopathies/prevention & control , Animals , Apoptosis/drug effects , Cells, Cultured , HEK293 Cells , Humans , Inflammation/metabolism , Inflammation/pathology , Inflammation/prevention & control , Inflammation Mediators/metabolism , Mice , Microglia/drug effects , Microglia/metabolism , Microglia/pathology , Neuroblastoma/metabolism , Neuroblastoma/pathology , Neuroblastoma/prevention & control , Neurons/metabolism , Neurons/pathology , Oxidation-Reduction , Tauopathies/metabolism , Tauopathies/pathologyABSTRACT
A simple and efficient protocol for the synthesis of a sphingosine starting from cost-effective phytosphingosine has been described. Two alternative synthetic pathway have been disclosed based on the use of two different kinds of protective groups for the protection of the amino group in the phytosphingosine. The protected phytosphingosine was subsequently transformed into sphingosine in 5 steps i.e. protection of the amine group, protection of 1,3-diol, leaving group insertion, elimination, and one-pot deprotection.
Subject(s)
Sphingosine/analogs & derivatives , Sphingosine/chemical synthesis , Molecular Structure , Sphingosine/chemistry , StereoisomerismABSTRACT
BACKGROUND: The F-box protein 7 (FBXO7) mutations have been identified in families with early-onset parkinsonism and pyramidal tract signs, and designated as PARK15. In addition, FBXO7 mutations were found in typical and young onset Parkinson's disease (PD). Evidence has also shown that FBXO7 plays an important role in the development of dopaminergic neurons and increased stability and overexpression of FBXO7 may be beneficial to PD. PURPOSE: We screened extracts of medicinal herbs to enhance FBXO7 expression for neuroprotection in MPP+-treated cells. METHODS: Promoter reporter assay in HEK-293 cells was used to examine the cis/trans elements controlling FBXO7 expression and to screen extracts of medicinal herbs enhancing FBXO7 expression. MTT assay was performed to assess cell viability of MPP+-treated HEK-293/SH-SY5Y cells. In addition, proteasome activity, mitochondrial membrane potential and FBXO7/TRAF2/GATA2 protein expression were evaluated. RESULTS: We demonstrated that -202--57 region of the FBXO7 promoter is likely to contain sequences that are bound by positive trans protein factors to activate FBXO7 expression and GATA2 is the main trans protein factor enhancing FBXO7 expression. Extracts of medicinal herbs Oenanthe javanica (Blume) DC. (Umbelliferae), Casuarina equisetifolia L. (Casuarinaceae), and Sorghum bicolor (L.) Moench (Gramineae) improved cell viability of both MPP+-treated HEK-293 and SH-SY5Y cells, rescued proteasome activity in MPP+-treated HEK-293 cells, and restored mitochondrial membrane potential in MPP+-treated SH-SY5Y cells. These protection effects of herbal extracts are acting through enhancing FBXO7 and decreasing TRAF2 expression, which is probably mediated by GATA2 induction. CONCLUSION: Collectively, our study provides new targets, FBXO7 and its regulator GATA2, for the development of potential treatments of PD.