18 research outputs found
Degenerative tendon matrix induces tenogenic differentiation of mesenchymal stem cells
Purpose
Mesenchymal stem cells (MSCs) react dynamically with the surrounding microenvironment to promote tissue-specific differentiation and hence increase targeted regenerative capacity. Extracellular matrix (ECM) would be the first microenvironment to interact with MSCs injected into the tissue lesion. However, degenerative tissues would have different characteristics of ECM in comparison with healthy tissues. Therefore, the influence of degenerative ECM on tissue-specific differentiation of MSCs and the formation of matrix composition need to be considered for the sophisticated therapeutic application of stem cells for tissue regeneration.
Methods
Human degenerative tendon tissues were obtained from patients undergoing rotator cuff repair and finely minced into 2â~â3mm fragments. Different amounts of tendon matrix (0.005g, 0.01g, 0.025g, 0.05g, 0.1g, 0.25g, 0.5g, 1g, and 2g) were co-cultured with bone marrow MSCs (BM MSCs) for 7days. Six tendon-related markers, scleraxis, tenomodulin, collagen type I and III, decorin, and tenascin-C, osteogenic marker, alkaline phosphatase (ALP), and chondrogenic marker, aggrecan (ACAN), were analyzed by qRT-PCR. Cell viability and senescence-associated beta-galactosidase assays were performed. The connective tissue growth factor was used as a positive control.
Results
The expressions of six tendon-related markers were significantly upregulated until the amount of tendon matrix exceeded 0.5g, the point where the mRNA expressions of all six genes analyzed started to decrease. The tendon matrix exerted an inhibitory effect on ACAN expression but had a negligible effect on ALP expression. Cell viability did not change significantly over the culture period. The amount of tendon matrix exceeding 0.01g significantly increased the SA-βgal activity of BM MSCs.
Conclusion
This study successfully demonstrated tendon ECM-stimulated tenogenesis of BM MSCs through an indirect co-culture system without the use of exogenous growth factors and the alteration of cellular viability. In contrast to the initial hypothesis, the tenogenesis of BM MSCs induced with the degenerative tendon matrix accompanied cellular senescence.This research was supported by a grant (HI20C0386) of the Korea Health Industry Development Institute (KHIDI) and a grant (22C0608L1-11) of the Korean Fund for Regenerative Medicine funded by Ministry of Science and ICT, and Ministry of Health and Welfare
Development of Parametric Trend Life Cycle Assessment for marine SOx reduction scrubber systems
In response to the impending international maritime regulation, MARPOL Annex VI Reg. 14, to curb sulphur oxides (SOx) arising from shipping activities, this paper aimed to evaluate the environmental impacts of the entire life cycle of three different SOx reduction scrubber systems: (1) âwet open-loopâ, (2) âwet closed-loopâ, and (3) âwet hybridâ. To achieve this goal, the paper developed âthe Parametric Trend Life Cycle Assessment (PT-LCA)â which was introduced to proceed the extensive analysis for a number of case ship studies and quantify various emissions, such as greenhouse gases (GHG), sulphur oxides (SOx), nitrogen oxides (NOx), associated with the proposed systems from cradle to grave. A case study designed with the database consisting of 1,565 ocean-going Ro-Ro vessels based on Lloydâs Register has revealed that, in terms of Global Warming Potential (GWP) and Acidification Potential (AP), closed-loop scrubbers were proven more environmentally friendly than open-loop scrubbers, but the opposite was true for Eutrophication Potential (EP). By identifying specific trends in scrubber systems in relation to various input parameters, the assessment contributed to improving environmental sustainability, as well as the total estimated amount of numerical environmental impacts that the scrubber systems have for the international fleets. The proposed framework enabled us not only to evaluate the different emission levels of systems applied to various ships but also to obtain the general trends of emission levels over ship parameters, which were expressed as formulae. The novelty of this paper can be placed on the provision of an insight into the optimal selection of scrubber systems depending on ship characteristics. It could also offer an insight into the improvement of current environmental regulations and guidelines by means of PT-LCA
Peritoneal Cells Mediate Immune Responses and Cross-Protection Against Influenza A Virus
Intraperitoneal inoculation with live influenza A virus confers protection against intranasal infections in mice and ferrets. However, the responses of peritoneal cells to influenza A virus have not been investigated. Here we show that intraperitoneal inoculation with A/WSN/1933 (H1N1) virus induced virus-reactive IgG production in the peritoneal cavity in mice. The infection resulted in substantial but transient B cell and macrophage depletion along with massive neutrophil infiltration, but virus growth was not detected. Influenza A viruses bound to Îą-2,6-linked sialic acids of B cells and macrophages and induced apoptotic death of peritoneal cavity cells. However, re-infection with A/WSN/1933 virus did not have adverse effects on immune cells most likely because of the neutralizing antibodies produced in response to the first exposure. Infection of BALB/c mice with A/WSN/1933 induced cross-protection against an otherwise lethal intraperitoneal dose of A/Hongkong/4801/2014 (H3N2) virus. This information suggests that immunological responses in the peritoneal cavity can induce effective defense against future virus infection. Considering the unexpected potent immunoregulatory activity of the peritoneal cells against influenza viruses, we suggest that comparative studies on various immune reactions after infection through different routes may contribute to better selection of vaccination routes in development of efficacious influenza vaccines
Degenerative tendon matrix induces tenogenic differentiation of mesenchymal stem cells
Abstract Purpose Mesenchymal stem cells (MSCs) react dynamically with the surrounding microenvironment to promote tissueâspecific differentiation and hence increase targeted regenerative capacity. Extracellular matrix (ECM) would be the first microenvironment to interact with MSCs injected into the tissue lesion. However, degenerative tissues would have different characteristics of ECM in comparison with healthy tissues. Therefore, the influence of degenerative ECM on tissueâspecific differentiation of MSCs and the formation of matrix composition need to be considered for the sophisticated therapeutic application of stem cells for tissue regeneration. Methods Human degenerative tendon tissues were obtained from patients undergoing rotator cuff repair and finely minced into 2â~â3 mm fragments. Different amounts of tendon matrix (0.005 g, 0.01 g, 0.025 g, 0.05 g, 0.1 g, 0.25 g, 0.5 g, 1 g, and 2 g) were coâcultured with bone marrow MSCs (BM MSCs) for 7 days. Six tendonârelated markers, scleraxis, tenomodulin, collagen type I and III, decorin, and tenascinâC, osteogenic marker, alkaline phosphatase (ALP), and chondrogenic marker, aggrecan (ACAN), were analyzed by qRTâPCR. Cell viability and senescenceâassociated betaâgalactosidase assays were performed. The connective tissue growth factor was used as a positive control. Results The expressions of six tendonârelated markers were significantly upregulated until the amount of tendon matrix exceeded 0.5 g, the point where the mRNA expressions of all six genes analyzed started to decrease. The tendon matrix exerted an inhibitory effect on ACAN expression but had a negligible effect on ALP expression. Cell viability did not change significantly over the culture period. The amount of tendon matrix exceeding 0.01 g significantly increased the SAâβgal activity of BM MSCs. Conclusion This study successfully demonstrated tendon ECMâstimulated tenogenesis of BM MSCs through an indirect coâculture system without the use of exogenous growth factors and the alteration of cellular viability. In contrast to the initial hypothesis, the tenogenesis of BM MSCs induced with the degenerative tendon matrix accompanied cellular senescence
Electrical and Optical Properties of Sb-doped SnO2 Thin Films Fabricated by Pulsed Laser Deposition
2023 Korean sexually transmitted infections guidelines for non-gonococcal bacterial infection (chlamydia, syphilis, etc.) by the Korean Association of Urogenital Tract Infection and Inflammation
Non-gonococcal sexually transmitted infections (STIs) include chlamydia, syphilis, and chancroids. Chlamydia is the most common STI caused by Chlamydia trachomatis and is mainly transmitted through sexual intercourse or vertical transmission at birth. Although symptoms are mostly absent or mild, untreated chlamydial infections in females can lead to pelvic inflammatory disease, chronic pelvic pain, and infertility due to the narrowing of fallopian tubes. Syphilis is caused by Treponema pallidum and is divided into phase I, phase II, latent syphilis, and phase III. The incidence of syphilis, including congenital syphilis, has significantly increased in the United States in recent years. The chronic status of this disease can significantly increase morbidity and potentially affect almost all body organs, which, in rare cases, can lead to death. Additionally, untreated maternal syphilis can lead to fetal death and fatal congenital infections in newborns. Chancroid is an STI caused by Haemophilus ducreyi, and its prevalence is gradually decreasing in Korea and worldwide. The symptoms include shallow genital ulcers with suppurative granulomatous inflammation and tender inguinal lymphadenopathy. Chancroids can be differentiated from syphilitic chancres based on their appearance. In contrast to painless chancres, chancroids are painful. Ureaplasma urealyticum, Ureaplasma parvum, and Mycoplasma hominis are considered symbiotic bacteria. Infections caused by these bacteria are usually not considered STIs and do not require treatment unless they are suspected of being associated with infertility. This article presents the 2023 Korean STI guidelines for non-gonococcal bacterial infections
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Effective writing instruction for students in grades 6 to 12: a best evidence meta-analysis
The current best evidence meta-analysis reanalyzed the data from a meta-analysis by Graham et al. (J Educ Psychol 115:1004â1027, 2023). This meta-analysis and the prior one examined if teaching writing improved the writing of students in Grades 6 to 12, examining effects from writing intervention studies employing experimental and quasi-experimental designs (with pretests). In contrast to the prior meta-analysis, we eliminated all N of 1 treatment/control comparisons, studies with an attrition rate over 20%, studies that did not control for teacher effects, and studies that did not contain at least one reliable writing measure (0.70 or greater). Any writing outcome that was not reliable was also eliminated. Across 148 independent treatment/control comparisons, yielding 1,076 writing effect sizes (ESs) involving 22,838 students, teaching writing resulted in a positive and statistically detectable impact on studentsâ writing (ES = 0.38). Further, six of the 10 writing treatments tested in four or more independent comparisons improved studentsâ performance. This included the process approach to writing (0.75), strategy instruction (0.59), transcription instruction (0.54), feedback (0.30), pre-writing activities (0.32), and peer assistance (0.59). In addition, the Self-Regulated Strategy Development model for teaching writing strategies yielded a statistically significant ES of 0.84, whereas other approaches to teaching writing strategies resulted in a statistically significant ES of 0.51. The findings from this meta-analysis and the Graham et al. (2023) review which included studies that were methodologically weaker were compared. Implications for practice, research, and theory are presented
Changes in patient perceptions regarding ChatGPT-written explanations on lifestyle modifications for preventing urolithiasis recurrence
Purpose Artificial Intelligence (AI) imitating human-like language, such as ChatGPT, has impacted lives throughout various multidisciplinary fields. However, despite these innovations, it is unclear how well its implementation will assist patients in clinical situations. We evaluated changes in patient perceptions regarding AI before and after reading a ChatGPT-written explanation. Materials and methods In total, 24 South Korean patients receiving urolithiasis treatment were surveyed through questionnaires. The ChatGPT explanatory note was provided between the first and second questionnaires, detailing lifestyle modifications for preventing urolithiasis recurrence. The study questionnaire was the Korean version of the General Attitudes toward Artificial Intelligence Scale, including positive and negative attitude items. Wilcoxon signed-rank tests were accomplished to compare questionnaire scores before and after receiving the explanatory note. A linear regression analysis with stepwise elimination was used to assess variable (demographic data) accuracy in predicting outcomes. Results There were significant differences between total negative questionnaire scores pre- and post-surveys of ChatGPT, but not in the positive scores. Among variables, only education level significantly influenced mean score differences in the negative questionnaires. Conclusions The negative perception change among urolithiasis patients after receiving the explanatory note provided by the AI chatbot program was observed, evidencing that patients with lower education levels expressed a more negative response. The explanatory note provided by the AI chatbot program could provoke an adverse change in AI perception. Negative human responses must be considered to improve and adapt new technology in health care. Only through changing patient perspectives will upgraded AI technology integrate into medical healthcare