Mesenchymal stem cell (MSC)-derived extracellular vesicles (exosomes) possess regeneration, cell proliferation, wound healing, and anti-senescence capabilities. The functions of exosomes can be ...modified by preconditioning MSCs through treatment with bio-pulsed reagents (
Thunb extract). However, the beneficial effects of bio-pulsed small extracellular vesicles (sEVs) on the skin or hair remain unknown. This study investigated the in vitro mechanistic basis through which bio-pulsed sEVs enhance the bioactivity of the skin fibroblasts and hair follicle cells. Avian-derived MSCs (AMSCs) were isolated, characterized, and bio-pulsed to produce AMSC-sEVs, which were isolated, lyophilized, characterized, and analyzed. The effects of bio-pulsed AMSC-sEVs on cell proliferation, wound healing, and gene expression associated with skin and hair bioactivity were examined using human skin fibroblasts (HSFs) and follicle dermal papilla cells (HFDPCs). Bio-pulsed treatment significantly enhanced sEVs production by possibly upregulating
expression in AMSCs. Bio-pulsed AMSC-sEVs contained more exosomal proteins and RNAs than the control. Bio-pulsed AMSC-sEVs significantly augmented cell proliferation, wound healing, and gene expression in HSFs and HFDPCs. The present study investigated the role of bio-pulsed AMSC-sEVs in the bioactivity of the skin fibroblasts and hair follicle cells as mediators to offer potential health benefits for skin and hair.
Incidence of invasive pneumococcal disease caused by antimicrobial-resistant Streptococcus pneumoniae types not included in pneumococcal conjugate vaccines has increased, including a penicillin- and ...meropenem-resistant serotype 15A-ST63 clone in Japan. During 2013–2017, we collected 206 invasive pneumococcal isolates in Taiwan for penicillin and meropenem susceptibility testing. We found serotypes 15B/C-ST83 and 15A-ST63 were the most prevalent penicillin- and meropenem-resistant clones. A transformation study confirmed that penicillin-binding protein (PBP) 2b was the primary meropenem resistance determinant, and PBP1a was essential for high-level resistance. The rate of serotype 15B/C-ST83 increased during the study. All 15B/C-ST83 isolates showed an ermB macrolide resistance genotype. Prediction analysis of recombination sites revealed 12 recombination regions in 15B/C-ST83 compared with the S. pneumoniae Spain23F-ST81 genome. Pneumococcal clones rapidly recombine to acquire survival advantages and undergo local expansion under the selective pressure exerted by vaccines and antimicrobial drugs. The spread of 15B/C-ST83 is alarming for countries with high antimicrobial pressure.
Coordinated multipoint joint transmission (JT) is a vital technique of the fifth-generation (5G) networks to increase throughput but causes a significant burden on network backhaul because the same ...user data must distribute to multiple base stations, called a JT cluster. Thus, many studies have explored how to reduce backhaul data traffic using caching user data at base stations. Millimeter wave (mmWave) mesh backhaul is a promising architecture for small cells to exchange cache data over 5G networks. However, this paper observes that inappropriate JT clusters and routing paths will result in unnecessary mmWave mesh backhaul bandwidth consumption such that the performance gain of the JT will be reduced. Therefore, in this paper, we study the JT clustering problem with the consideration of caches at base stations and mmWave mesh backhaul. The objective is to minimize total backhaul traffic while satisfying the data rate requirement of each user under limited radio resource units. We propose a two-stage algorithm based on dynamic programming approach to solve the problem. We prove that the dynamic programming algorithm can find an optimal solution for our subproblem. The simulation results provide several insights and show that compared with two baseline algorithms, our proposed algorithm can significantly reduce more backhaul bandwidth consumption.
Abstract
Background
Streptococcus pneumoniae
is a common cause of post-influenza secondary bacterial infection, which results in excessive morbidity and mortality. Although 13-valent pneumococcal ...conjugate vaccine (PCV13) vaccination programs have decreased the incidence of pneumococcal pneumonia, PCV13 failed to prevent serotype 3 pneumococcal disease as effectively as other vaccine serotypes. We aimed to investigate the mechanisms underlying the co-pathogenesis of influenza virus and serotype 3 pneumococci.
Methods
We carried out a genome-wide screening of a serotype 3
S. pneumoniae
transposon insertion mutant library in a mouse model of coinfection with influenza A virus (IAV) to identify the bacterial factors required for this synergism.
Results
Direct, high-throughput sequencing of transposon insertion sites identified 24 genes required for both coinfection and bacterial infection alone. Targeted deletion of the putative aminotransferase (
PA
) gene decreased bacterial growth, which was restored by supplementation with methionine. The bacterial burden in a coinfection with the
PA
gene deletion mutant and IAV in the lung was lower than that in a coinfection with wild-type pneumococcus and IAV, but was significantly higher than that in an infection with the
PA
gene deletion mutant alone. These data suggest that IAV infection alters host metabolism to benefit pneumococcal fitness and confer higher susceptibility to pneumococcal infection. We further demonstrated that bacterial growth was increased by supplementation with methionine or IAV-infected mouse lung homogenates.
Conclusions
The data indicates that modulation of host metabolism during IAV infection may serve as a potential therapeutic intervention against secondary bacterial infections caused by serotype 3 pneumococci during IAV outbreaks in the future.
Genomic changes in Mycoplasma pneumoniae caused by adaptation to environmental or ecologic pressures are poorly understood. We collected M. pneumoniae from children who had confirmed pneumonia in ...Taiwan during 2017-2020. We used whole-genome sequencing to compare these isolates with a worldwide collection of current and historical clinical strains for characterizing population structures. A phylogenetic tree for 284 strains showed that all sequenced strains consisted of 5 clades: T1-1 (sequence type ST1), T1-2 (mainly ST3), T1-3 (ST17), T2-1 (mainly ST2), and T2-2 (mainly ST14). We identified a putative recombination block containing 6 genes (MPN366‒371). Macrolide resistance involving 23S rRNA mutations was detected for each clade. Clonal expansion of macrolide resistance occurred mostly within subtype 1 strains, of which clade T1-2 showed the highest recombination rate and genome diversity. Functional characterization of recombined regions provided clarification of the biologic role of these recombination events in the evolution of M. pneumoniae.
Liver diseases, including viral hepatitis, liver cirrhosis, and liver cancer, mostly remain silent until the late stages and pose a continuing threat to millions of people worldwide. Liver ...transplantation is the most appropriate solution in the case of liver failure, but it is associated with hepatic ischemia and reperfusion (I/R) injury which severely reduces the prognosis of the patients. In order to ameliorate I/R injury, we investigated the potential of bracteanolide A, from the herb Tradescantia albiflora Kunth in protecting the liver from I/R injury. We first determined the protective effect of bracteanolide A against oxidative stress and DNA damage using HepG2 hepatocyte cell line and then assessed the levels of inflammatory cytokines and antioxidant proteins in response to hepatic insult using an animal model of hepatic I/R injury. The results showed bracteanolide A greatly enhanced cell survival and decreased reactive oxygen species (ROS) production under H2O2 induction. It also upregulated the expression of nuclear factor (erythroid‐derived 2)‐like2 (Nrf2) and its downstream cytoprotective proteins NAD(P)H quinone oxidoreductase 1 (NQO1) and heme oxygenase‐1 (HO‐1). Bracteanolide A effectively reduced the severity of liver lesions in I/R‐injured rats revealed by histological analysis and significantly decreased the levels of alanine transaminase (ALT), aspartate transaminase (AST), cyclooxygenase‐2, and inflammatory cytokines interleukin (IL)‐1β and tumor necrosis factor (TNF)‐α. Bracteanolide A preconditioning effectively protected the liver from I/R damage in the animal model, and this easily applied procedure may provide a new means to ameliorate hepatic I/R injury during liver surgeries.
Bracteanolide A, the active compound from Tradescantia albiflora Kunth, exhibits antioxidative and cytoprotective potentials. Moreover, bracteanolide A given prior to inducing hepatic ischemia and reperfusion in rats effectively lessens damage to the liver through lowering levels of ALT, AST, Suzuki score for histopathological lesions, and inflammatory cytokines, as well as restoring liver morphology. Bracteanolide A may be a feasible hepatoprotective agent against liver ischemia and reperfusion injury.
Results from studies investigating the association between coffee consumption and osteoporosis or bone mineral density (BMD) have been inconsistent. This longitudinal study was performed to assess ...the effect of coffee drinking on bone health of Taiwanese adults.
Data were retrieved from the Li-Shin (Landseed) Hospital in Taoyuan City. In 2006, 6152 participants completed a questionnaire on coffee drinking and other lifestyle factors. In 2014, 5077 of them were followed up. Nonetheless, a total of 2395 participants with incomplete data were excluded. The final analyses included 2682 participants comprising 1195 men and 1487 women (706 premenopausal and 781 postmenopausal). T-scores were derived from the osteo-sono assessment index (OSI) which is a surrogate of BMD. Coffee drinking was categorized as "no, medium, and high" based on the number of cups that were consumed per week in both 2006 and 2014.
In general, medium and high coffee drinking were associated with higher T-scores. However, significant results were observed only among high drinkers (β = 0.158; P = 0.0038). Nonetheless, the test for linear trend was significant (P = 0.0046). After stratification by sex, medium and high coffee drinking were associated with higher T-scores. However, significant results were prominent only among high male drinkers (β = 0.237; P = 0.0067) and the test for trend was significant (P = 0.0161). Based on menopausal status, coffee drinking was associated with higher T-scores. Nevertheless, significant results were found only among premenopausal women (β = 0.233; P = 0.0355 and β = 0.234; P = 0.0152 for medium and high coffee drinking, respectively. The test for linear trend was significant (P = 0.0108).
Coffee drinking was significantly associated with higher T-scores hence, a lower risk of osteoporosis in men and premenopausal women.
Bamboo-fiber-reinforced polymers have gained popularity in numerous industries because of their mechanical properties, lightweight, and ecological benefits. In this study, to determine the effects of ...textile structure on the impact resistance performance of bamboo-textile-reinforced polymers (BTRPs), we evaluated three impact modes: simple support beam (SSB), drop weight, and Charpy impact. We then used 3D X-ray scanning to determine the effects of the textile structure and impact modes on the microscopic fracture and crack development. The results indicated that the woven structure allowed for energy transmission in all directions during the drop weight impact test. During the SSB impact test, the large quantity of bamboo tows parallel to the major axis of the specimen increased the absorbed energy. When additional layers were added in the loading direction, the deflection of the entire specimen decreased, thus leading to lower absorbed energy. According to 3D X-ray images and quasi-static bending fracture results, similar fracture patterns appeared on dynamic and static loaded specimens. Consequently, the energy required for internal fracture and the strain energy of deflection are the two significant reasons that enable the excellent impact resistance performance of BTRPs.
•Three impact modes include simple support beam, drop weight, and Charpy were conducted.•Effects of woven structure factors on impact strength, absorbed energy and fractography were determined.•3D Xray technique was used to identify fracture modes and fracture pattern.•The impact energy absorbed is nearly equal to the sum of the energy required for fracturing, crack propagation and the work done by deformation.
Mycoplasma pneumoniae is currently the most commonly detected bacterial cause of childhood community-acquired pneumonia in several countries. Of note, clonal expansion of macrolide-resistant ST3 ...occurred in Japan and South Korea. An alarming surge in macrolide resistance complicates the treatment of pneumonia. We aimed to evaluate the clinical manifestation and clonal relatedness of M. pneumoniae circulating among children in Taiwan.
We prospectively enrolled 626 children with radiologically confirmed pneumonia between 2017 and 2019. An M. pneumoniae infection was suspected on clinical grounds, and tested by real-time PCR and oropharyngeal swab cultures. We used multilocus sequence typing and whole-genome sequencing to characterize the genetic features of M. pneumoniae.
A total of 226 children with M. pneumoniae pneumonia were enrolled. Macrolide resistance was found in 77% (174/226) of patients. Multi-locus sequence typing revealed that ST3 (n = 93) and its single-locus variant ST17 (n = 84) were the predominant clones among macrolide-resistant strains. ST17 presented clinical characteristics comparable to its ancestor ST3. On multivariate analysis, macrolide resistance (OR 3.5; 95% CI 1.4–8.5; p 0.007) was independently associated with fever >72 hours after macrolide treatment. By whole-genome sequencing, prediction analysis of recombination sites revealed one recombination site in ST3 and ST17 compared with M29 (a macrolide-sensitive ST3 strain isolated from China in 2005) containing cytadhesin MgpC-like protein, RepMP4 and RepMP5. ST17 had another recombination site containing an adhesin and RepMP2/3.
In addition to macrolide resistance, ST3 and its ST17 variant might evolve through recombination between repetitive sequences and non-P1 cytadhesins for persistent circulation in Taiwan.
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