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This study explored the composition of essential oil (EO) and the first phytotoxic screening of EO obtained from the stems and leaves of Mentha vagans Boriss (MVEO) via hydro-distillation technique. The EO ingredients were detected through Gas Chromatography-Mass Spectrometry (GC-MS). GC-MS analysis revealed that MVEO contained 49 constituents, constituting 93.95 % of the total oil. Among MVEO constituents, dihydrocarvone was observed as the dominant constituent (24.14 %), followed by D-carvone (16.28 %) and piperitone (18.14 %). The phytotoxic effects of MVEO and its dominant compounds were examined against Amaranthus retroflexus, Lolium perenne, and Poa annua. Significant inhibition was observed by MVEO in comparison with the major constituents and their mixture, suppressing the seedling growth of tested species at the lowest dosage (0.01â mg/mL); in general, seedling growth of all tested species was markedly inhibited when applied concentration of the EO and its constituents reached 0.05â mg/mL. Our results also indicated that constituents other than the dominant compounds of MVEO possessed considerable phytotoxic effects because the EO's activity was stronger than its major constituents and their mixture. Thus, additional studies are required to investigate MVEO and its constituents and commercialize them as environment-friendly bio-herbicides.
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This article discusses the application of artificially intelligent robots within eldercare and explores a series of ethical considerations, including the challenges that AI (Artificial Intelligence) technology poses to traditional Chinese Confucian filial piety. From the perspective of Confucian ethics, the paper argues that robots cannot adequately fulfill duties of care. Due to their detachment from personal relationships and interactions, the "emotions" of AI robots are merely performative reactions in different situations, rather than actual emotional abilities. No matter how "humanized" robots become, it is difficult to establish genuine empathy and a meaningful relationship with them for this reason. Even so, we acknowledge that AI robots are a significant tool in managing the demands of elder care and the growth of care poverty, and as such, we attempt to outline some parameters within which care robotics could be acceptable within a Confucian ethical system. Finally, the paper discusses the social impact and ethical considerations brought on by the interaction between humans and machines. It is observed that the relationship between humans and technology has always had both utopian and dystopian aspects, and robotic elder care is no exception. AI caregiver robots will likely become a part of elder care, and the transformation of these robots from "service providers" to "companions" seems inevitable. In light of this, the application of AI-augmented robotic elder care will also eventually change our understanding of interpersonal relationships and traditional requirements of filial piety.
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Sepsis is a life-threatening condition characterized by a harmful host response to infection with organ dysfunction. Annually about 20 million people are dead owing to sepsis and its mortality rates is as high as 20%. However, no studies have been carried out to investigate sepsis from the system biology point of view, as previous research predominantly focused on individual genes without considering their interactions and associations. Here, we conducted a comprehensive exploration of genome-wide expression alterations in both mRNAs and long non-coding RNAs (lncRNAs) in sepsis, using six microarray datasets. Co-expression networks were conducted to identify mRNA and lncRNA modules, respectively. Comparing these sepsis modules with normal modules, we observed a homogeneous expression pattern within the mRNA/lncRNA members, with the majority of them displaying consistent expression direction. Moreover, we identified consistent modules across diverse datasets, consisting of 20 common mRNA members and two lncRNAs, namely CHRM3-AS2 and PRKCQ-AS1, which are potential regulators of sepsis. Our results reveal that the up-regulated common mRNAs are mainly involved in the processes of neutrophil mediated immunity, while the down-regulated mRNAs and lncRNAs are significantly overrepresented in T-cell mediated immunity functions. This study sheds light on the co-expression patterns of mRNAs and lncRNAs in sepsis, providing a novel perspective and insight into the sepsis transcriptome, which may facilitate the exploration of candidate therapeutic targets and molecular biomarkers for sepsis.
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RNA Longo não Codificante , Sepse , Humanos , Biologia , Imunidade Celular , RNA Mensageiro , Receptor Muscarínico M3RESUMO
Forming olivine-structured Li(Mn,Fe)PO4 solid solution is theoretically a feasible way to improve the energy density of the solid solutions for lithium ion batteries. However, the Jahn-Teller active Mn3+ in the solid solution restricts their energy density and rate performance. Here, as demonstrated by operando X-ray diffraction, we show that equimolar LiMn0.5Fe0.5PO4 solid solution nanocrystals undergo a single-phase transition during the whole (de)lithiation process, with a feature of zero lithium miscibility gap, which endows the nanocrystals with excellent electrochemical properties. Specifically, the energy density of LiMn0.5Fe0.5PO4 reaches 625 Wh kg-1, which is 16% higher than that of LiFePO4. Moreover, the high-performance LiMn0.5Fe0.5PO4 nanocrystals are prepared by a microwave-assisted hydrothermal synthesis in pure water.
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Two previously undescribed polycyclic polyprenylated acylphloroglucinols, hyperacmosins R-S (1-2), were obtained from the aerial parts of Hypericum acmosepalum. Their structures were elucidated by extensive spectroscopic analysis and electronic circular dichroism calculation (ECD). Compound 1 featured an unprecedented 5,8-spiroketal subunit as well as the loss of C-2' carbonyl in the phloroglucinol ring. In addition, compounds 1 and 4 showed weak hepatoprotective activity against paracetamol-induced HepG2 cell damage at 10 µm. The plausible biosynthetic pathway of 1 was proposed via a retro-Clasisen reaction and decarboxylation.
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Hypericum , Acetaminofen , Furanos , Hypericum/química , Estrutura Molecular , Floroglucinol/química , Floroglucinol/farmacologia , Compostos de EspiroRESUMO
BACKGROUND: Faecal microbiota transplantation (FMT) is an effective therapy for recurrent Clostridium difficile infections and chronic gastrointestional infections. However, the risks of FMT and the selection process of suitable donors remain insufficiently characterized. The eligibility rate for screening, underlying microbial basis, and core ethical issues of stool donors for FMT are yet to be elucidated in China. RESULTS: The potential stool donors were screened from December 2017 to December 2019 with the help of an online survey, clinical assessments, and stool and blood testing. Bioinformatics analyses were performed, and the composition and stability of gut microbiota in stool obtained from eligible donors were dynamically observed using metagenomics. Meanwhile, we build a donor microbial evaluation index (DoMEI) for stool donor screening. In the screening process, we also focused on ethical principles and requirements. Of the 2071 participants, 66 donors were selected via the screening process (3.19% success rate). Although there were significant differences in gut microbiota among donors, we found that the changes in the gut microbiota of the same donor were typically more stable than those between donors over time. CONCLUSIONS: DoMEI provides a potential reference index for regular stool donor re-evaluation. In this retrospective study, we summarised the donor recruitment and screening procedure ensuring the safety and tolerability for FMT in China. Based on the latest advances in this field, we carried out rigorous recommendation and method which can assist stool bank and clinicians to screen eligible stool donor for FMT.
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Seleção do Doador/métodos , Transplante de Microbiota Fecal/métodos , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Metagenômica/métodos , Doadores de Tecidos , Adolescente , Adulto , China , Infecções por Clostridium/terapia , Biologia Computacional/métodos , Feminino , Humanos , Masculino , Estudos Retrospectivos , Adulto JovemRESUMO
INTRODUCTION: Broad issues relating to filial piety and ethical dilemmas of families and care practitioners in residential care were discussed as part of an international networking project. It is meaningful to explore the different roles and responsibilities of participants in residential care in the context of China's filial piety. Older residents and their children are part of this caring process, which might be significantly different from that in Western countries. However, only a little amount of research related to this topic has been conducted. OBJECTIVE: This study aimed to identify and describe the roles and responsibilities of a nursing professional, manager, older person, and her children, as well as other mutual contacts in residential care, based on the context of Chinese filial piety culture. METHODS: The study was conducted as a case study. The product of the analysis, themes, or categories that describe the phenomenon, content analysis method was applied. After a consultation with a group of experts on research on older adults, a specific nursing home was selected in Xiamen City, China. This case study emphasized the roles and responsibilities of a nursing professional, manager, the older resident, and her children as they related to the care of older adult. The data, which consisted of interviews with four participants, were collected using a semi-structured interview method. Inductive content analysis was applied to analyze data. ETHICAL CONSIDERATIONS: Permission to conduct the interviews received ethical approval from the participating organization based on national standards. The elements of voluntary participation, anonymity, and confidentiality on the part of the respondent were explained. FINDINGS: The analysis resulted in four participants, with some variation of roles and responsibilities, describing staffing level and competence and their behavior for reducing the accident of the older adult, and the children of older adult influencing the quality of taking care of the older adult, based on the filial piety. The nursing home residents were described as becoming increasingly complex with a subsequent demand for increased spiritual support. There was variation in roles and responsibilities among four participants, but their contributions adjusting was an overall focus. Manager plays a considerable role in the future development of the institution, as a resource allocator, and decision-maker. Nursing professional is the main personnel serving as a link among staffs. The older adult herself adjust mentally and actively with the aging process, and some of them can be able to burden in taking care of her grandchildren or can be rehired and still have a distinct role in society. Children are required to fulfill their obligations to their parents, which involves supports of care, spiritual and economy. Several factors such as managers and nursing professional competence and their cooperation, various aspects of supports from their children based on the filial piety, and adequate communication and self-adjusting of the older adult, were recognized as factors affecting the process of taking care of the older adult. DISCUSSION: New information was produced to serve as theoretical guidelines in managing nursing homes, the training of nursing staff, preservation of the filial piety culture, and encouraging self-care among older people in the new era. CONCLUSION: A variety of roles and responsibilities for a nursing professional, manager, MrsWang and her children was identified in the older adult care process. Several factors to manager's and nursing professional's experience of the resource situation and competence level, and also adequate communication and self-adjusting of the older adult were suggested to affect the effect of taking care of the older adult. The older adults were perceived as more complex with more physical and mental problems but inadequate care from family members forcing the older adult from home care to a nursing home. A nursing home seems to have a higher nursing competence and be well-suited for the needs of the older adult, on the other hand, filial piety and self-care are also needed to play an important role in taking care of the older adult.
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Família , Pais , Idoso , Criança , China , Comunicação , Feminino , Humanos , Casas de SaúdeRESUMO
PURPOSE OF REVIEW: This review was undertaken to analyze the main reasons behind the limited development of hospice care in China, and to put forward some suggestions. RECENT FINDINGS: Although the Chinese government has increased its support for hospice care in recent years, however, owing to the lack of education around hospice care and the heavy influence of the traditional Chinese Confucian concept of "filial piety," many individuals resist hospice care. Moreover, due to impaired patient rights, inadequate composition of hospice care teams, unbalanced geographical distribution, and limited service range, the development of hospice care in China is hindered. Hospice care education and continued training should be popularized and the government should strengthen the legal structure of the medical system to protect the rights of patients, families, and medical staff to promoting social support for hospice care. Through graded diagnosis and referral systems in medical institutions to integrate medical resources and expand the range of hospice care services.
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Cuidados Paliativos na Terminalidade da Vida , China , Cuidados Paliativos na Terminalidade da Vida/organização & administração , Cuidados Paliativos na Terminalidade da Vida/psicologia , Cuidados Paliativos na Terminalidade da Vida/normas , Direitos Humanos , HumanosRESUMO
In order to find out whether the geomagnetic storms and large-mega earthquakes are correlated or not, statistical studies based on Superposed Epoch Analysis (SEA), significance analysis, and Z test have been applied to the Dst index data and M ≥ 7.0 global earthquakes during 1957-2020. The results indicate that before M ≥ 7.0 global earthquakes, there are clearly higher probabilities of geomagnetic storms than after them. Geomagnetic storms are more likely to be related with shallow earthquakes rather than deep ones. Further statistical investigations of the results based on cumulative storm hours show consistency with those based on storm days, suggesting that the high probability of geomagnetic storms prior to large-mega earthquakes is significant and robust. Some possible mechanisms such as a reverse piezoelectric effect and/or electroosmotic flow are discussed to explain the statistical correlation. The result might open new perspectives in the complex process of earthquakes and the Lithosphere-Atmosphere-Ionosphere (LAI) coupling.
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In infrared systems, the stray radiation from optical elements and mechanical structures is an important factor affecting quantitative measurements because the irradiance on detectors due to stray radiation depends on the operating temperature of the optical system. Without correcting for this effect, the accuracy of quantitative measurements made with such systems is degraded. To better understand this phenomenon, we derive herein a mathematical model that describes stray radiation as a function of temperature and use the model to quantitatively analyze the stray radiation of an infrared system at different operating temperatures. To test the theory, we use it to calculate the stray radiation from an experimental infrared system comprising a Cassegrain reflector in the first stage and a transmission mirror in the second stage. The maximum relative error between theory and experiment was 8.72%. At the same time, a corrective measure of stray radiation is provided to account for the effect of stray radiation on quantitative measurements. The relative error of quantitative measurements decreases from 2.16% to 0.31%. The measurement accuracy of the infrared system has been improved effectively.
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Our understanding of the complexity of the oral biome and of the role of the various constituent bacteria in the aetiology of dental disease is growing. Probiotics and their relationship with prebiotics, as well as other microbiome-based interventions, could be useful in preventing and treating dental disease and in promoting oral health. However, given the promise and early stage of this treatment approach, there are also a number of ethical, social and regulatory issues associated with innovative probiotic therapy. In this article, a brief update is given on contemporary theories of the aetiology and management of the two commonest dental diseases, and on the roles of pre- and probiotics and oral biome transplant in the management of these diseases. The focus is primarily on four core issues: informed consent, risk-benefit assessment, how to determine suitable healthy donors, and commercialization and regulation. We discuss the safety and benefits of oral probiotics, not only concerning the products and quality control during their manufacture, but also regarding the depth of public knowledge about this topic. We point out that the requirement of listing ingredients honestly might be insufficient, and that the prevalent rhetoric of 'natural' and 'organic' as well as some health claims in the translational, innovative probiotic industry and markets are themselves misleading and should be carefully scrutinized. Finally, we suggest an ethical imperative to find a balance between scientific research and industry, and public health in the regulation of probiotics.
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Promoção da Saúde/ética , Boca/microbiologia , Saúde Bucal , Prebióticos/administração & dosagem , Probióticos/uso terapêutico , Doenças Estomatognáticas/diagnóstico , Doenças Estomatognáticas/terapia , HumanosRESUMO
A 22-year-old man suffered from acute pulmonary hemorrhage and deteriorated renal function occurred within 3 days after traumatic brain injury. Mechanical ventilation cannot correct his severe hypoxemia, therefore, venoarterial extracorporeal membrane oxygenation (VA-ECMO) support was initiated and finally resolved his hypoxemia. Concomitantly, continuous renal replacement therapy was performed to improve his kidney function. Although no anti-glomerular basement membrane (anti-GBM) antibody was detected in serum, Goodpasture's syndrome was considered. After treated with methylprednisolone pulse therapy and plasmapheresis, his renal function was significantly improved. ECMO was eventually discontinued after 60 hours of treatment and extubated on day 10. He was discharged home with normal pulmonary and renal functions.
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Doença Antimembrana Basal Glomerular/terapia , Lesões Encefálicas Traumáticas/terapia , Oxigenação por Membrana Extracorpórea , Metilprednisolona/administração & dosagem , Plasmaferese , Adulto , Humanos , MasculinoRESUMO
China's current basic health insurance reform aims at promoting equity in the economic accessibility of health services for all citizens, to better ensure healthcare justice. Therefore, it is important to assess equity not only from a socioeconomic perspective but also from an ethical angle. This article investigates the basic health insurance system of Hunan Province in China by focusing on insurance types as well as their classification standards, mechanisms, and utilization according to local policy documents and data. This study demonstrates the reforming achievements and the inequity of institutional design according to two interrelated dimensions: equal opportunity of access to healthcare insurance and reducing inequality in insurance benefits. The article concludes that to achieve opportunity equity and outcome fairness, the reform should focus on designing the system to promote equity with respect to procedures and rules and to be more attentive to the interests of vulnerable groups and especially to rural residents.
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Reforma dos Serviços de Saúde , Seguro Saúde/organização & administração , China , Acessibilidade aos Serviços de Saúde , Disparidades em Assistência à Saúde , População RuralRESUMO
Fecal microbiota transplantation (FMT) has demonstrated efficacy and is increasingly being used in the treatment of patients with recurrent Clostridium difficile infection. Despite a lack of high-quality trials to provide more information on the long-term effects of FMT, there has been great enthusiasm about the potential for expanding its applications. However, FMT presents many serious ethical and social challenges that must be addressed as part of a successful regulatory policy response. In this article, we draw on a sample of the scientific and bioethics literatures to examine clusters of ethical and social issues arising in five main areas: (1) informed consent and the vulnerability of patients; (2) determining what a "suitable healthy donor" is; (3) safety and risk; (4) commercialization and potential exploitation of vulnerable patients; and (5) public health implications. We find that these issues are complex and worthy of careful consideration by health care professionals. Desperation of a patient should not be the basis for selecting treatment with FMT, and the patient's interests should always be of paramount concern. Authorities must prioritize development of appropriate and effective regulation of FMT to safeguard patients and donors, promote further research into safety and efficacy, and avoid abuse of the treatment.
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Temas Bioéticos , Infecções por Clostridium/terapia , Transplante de Microbiota Fecal/ética , Políticas , Controle Social Formal , Beneficência , Análise Ética , Pessoal de Saúde , Humanos , Consentimento Livre e Esclarecido , Saúde Pública , Risco , Doadores de TecidosRESUMO
BACKGROUND: Fecal microbiota transplantation (FMT) is reportedly the most effective therapy for relapsing Clostridium Difficile infection (CDI) and a potential therapeutic option for many diseases. It also poses important ethical concerns. This study is an attempt to assess clinicians' perception and attitudes towards ethical and social challenges raised by fecal microbiota transplantation. METHODS: A questionnaire was developed which consisted of 20 items: four items covered general aspects, nine were about ethical aspects such as informed consent and privacy issues, four concerned social and regulatory issues, and three were about an FMT bank. This was distributed to participants at the Second China gastroenterology and FMT conference in May 2015. Basic descriptive statistical analyses and simple comparative statistical tests were performed. RESULTS: Nearly three quarters of the 100 respondents were gastro-enterologist physicians. 89% of all respondents believed FMT is a promising treatment modality for some diseases and 88% of whom chose clinical efficacy as the primary reason for recommending FMT. High expectation from patients and pressure on clinicians (33%) was reported as the most frequent reasons for not recommending FMT. The clinicians who had less familiarity with FMT reported significantly more worry related to the dignity and psychological impact of FMT compared to those who have high familiarity with FMT (51.6% vs 27.8%, p = 0.021).More than half of the respondents (56.1%) were concerned about the commercialization of FMT, although almost one in five respondents did not see this as a problem. CONCLUSIONS: We found most respondents have positive attitudes towards FMT but low awareness of published evidence. Informed consent for vulnerable patients, privacy and protection of donors were perceived as the most challenging ethical aspects of FMT. This study identified areas of limited knowledge and ways of addressing ethical issues and indicates the need to devise the education and training for clinicians on FMT.
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Atitude do Pessoal de Saúde , Temas Bioéticos , Infecções por Clostridium/terapia , Transplante de Microbiota Fecal , Relações Médico-Paciente , Médicos , Conscientização , China , Emoções , Transplante de Microbiota Fecal/ética , Transplante de Microbiota Fecal/psicologia , Gastroenterologistas , Gastroenterologia , Humanos , Consentimento Livre e Esclarecido , Privacidade , Inquéritos e Questionários , Doadores de TecidosRESUMO
BACKGROUND: The mouse strain BALB/c deficient in IL-1 receptor antagonist protein (Il-1ra) develops spontaneous arthritis disease (SAD) while the strain DBA/1 IL1rn (-/-) with the same deficiency does not. Previously, we mapped a QTL on chromosome 1 for SAD and then developed a congenic mouse strain BALB.D1-1(-/-) that contains the QTL genomic fragment associated with resistance from DBA/1(-/-) on a BALB/c(-/-) background. The congenic strain was relatively resistant to spontaneous arthritis and had delayed onset and reduced severity of disease. We obtained whole genome expression profiles from the spleen of the congenic strain BALB.D1-1(-/-) and four other strains, the wild type BALB/c, DBA/1 and the deficient DBA/1 IL1rn (-/-) and the BALB/c IL1rn (-/-). We then compared the similarities and differences between the congenic strain and the four parental strains. Here we report the selected potential causal genes based on differential expression levels as well as function of genes. RESULTS: There is a considerable number of genes that are differentially expressed between the congenic strain and the three parental strains, BALB/c, DBA/1, and DBA/1(-/-). However there only a few differentially expressed genes were identified by comparing the congenic strain and the BALB/c(-/-)strain. These differentially expressed genes are mainly from T-cell receptor beta chain (Tcrb) and interferon-activatable protein (Ifi) genes. These genes are also differentially expressed between congenic strain and BALB/c strains. However, their expression levels in the congenic strain are similar to that in DBA/1 and DBA/1(-/-). The expression level of Tcrb-j gene is positively associated with two genes of Ifi gene 200 cluster. CONCLUSIONS: Decreased expression levels of Ifi genes is associated to the increased resistance to spontaneous arthritis disease and with down regulation of expressions of Tcrb genes in the mouse congenic strain. Ifi genes may play an important role in the susceptibility to SAD in mice.
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Artrite/genética , Genes Codificadores da Cadeia beta de Receptores de Linfócitos T/genética , Proteína Antagonista do Receptor de Interleucina 1/genética , Proteínas Nucleares/genética , Fenótipo , Animais , Simulação por Computador , Feminino , Perfilação da Expressão Gênica , Patrimônio Genético , Camundongos , Camundongos Congênicos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Camundongos Mutantes , Análise em Microsséries , Mutação/genética , Especificidade da EspécieRESUMO
BACKGROUND: To understand the role of genetic factors on chromosome 1 in the regulation of spontaneous arthritis in mice deficient in IL-1 receptor antagonist protein (IL_1RA), we previously used speed congenic breeding to transfer the QTL region from DBA/1(-/-) mice that are resistant to spontaneous arthritis into BALB/c(-/-) mice which are susceptible. We were able to establish two congenic strains which exhibited a delayed onset and reduced severity of disease. In this study, we asked a different set of questions. How will the QTL region from BALB/c(-/-) interact with the rest of the genome in the DBA/1(-/-) background? Will the DBA/1(-/-) mice become susceptible to spontaneous arthritis if the QTL genomic region on chromosome 1 was replaced with the genomic fragment of the same region from BALB/c(-/-)? We conducted the congenic breeding with the similar procedure as that of congenic strains with BALB/c(-/-) background. RESULT: Instead of BALB/c(-/-), DBA/1(-/-) was used as the recurrent parent while BALB/c(-/-) was used as the donor parent. By the 6(th) generation we determined that all of the chromosomes in the progeny were of DBA/1(-/-) origin with the exception of the QTL portion of chromosome 1 which is heterozygous of BALB/c(-/-) and DBA/1(-/-) origin. We then intercrossed selected mice to produce homozygous strains containing the homozygous genomic region of BALB/c(-/-) on chromosome 1, while the rest of genome are homozygous DBA/1(-/-). This strain was observed for the development of spontaneous arthritis. Up to 9 weeks of age, both congenic strain and DBA/1(-/-) did not develop arthritis. However, after 9 weeks, the congenic strain started to exhibit signs of arthritis, while the DBA/1(-/-) remained free from disease. CONCLUSION: The result indicates a strong influence of genetic factor(s) on the QTL of chromosome 1 on the susceptibility to spontaneous arthritis. Identification of genetic factors within this QTL region in the future will significantly enhance our understanding of molecular mechanism of spontaneous arthritis.
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Artrite/genética , Cromossomos de Mamíferos/genética , Locos de Características Quantitativas , Animais , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Camundongos KnockoutRESUMO
The interplay between unconventional superconductivity and the ordering of charge/spin density wave is one of the most vital issues in both condensed matter physics and material science. The Ti-based compound BaTi2As2O, which can be seen as the parent phase of superconducting BaTi2Sb2O, has a layered structure with a space group P4/mmm, similar to that of cuprate and iron-based superconductors. This material exhibits a charge density wave (CDW) ordering transition revealed by an anomaly at around 200 K in transport measurements. Here, we report the synthesis and systematical study of the physical properties in Cr-doped BaTi(2-x)Cr(x)As2O (x = 0-0.154) and demonstrate that the transition temperature of the CDW ordering is suppressed gradually by the doped Cr element. The magnetization measurements confirm the evolution of the CDW ordering transition. These observed behaviors are similar to that observed in iron-based superconductors, but no superconductivity emerges down to 2 K. In addition, the first-principles calculations are also carried out for well-understanding the nature of experimental observations.
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For decades, mouse and other rodents have been used for the study of oxidative or related studies such as the effect of fluoride. It is known that rodents normally synthesize their own vitamin C (VC) due to the presence of a key enzyme in ascorbic acid synthesis, l-gulono-lactone-γ-oxidase (Gulo), while humans do not have the capacity of VC synthesis due to the deletion of most parts of the GULO gene. The spontaneous fracture (sfx) mouse recently emerged as a model for study of VC deficiency. We investigated the effect of fluoride on liver cells from wild type Balb/c and sfx mice. We found that activities of SOD, GPx, and CAT were reduced in both wild type and sfx mice; however, the amount of reduction in the sfx cells is more than that in Balb/c cells. In addition, while both cells increased MDA, the increase in the sfx cells is greater than that in Balb/c cells. Gene networks of Sod, Gpx, and Cat in the liver of humans and mice are also different. Our study suggests that reaction to fluoride in vitamin C deficient mice might be different from that of wild type mice.
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Deficiência de Ácido Ascórbico/metabolismo , Fluoretos/farmacologia , Fluorose Dentária/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos KnockoutRESUMO
SnTe, an environmentally friendly thermoelectric material, has garnered widespread scholarly interest owing to its lead-free nature; however, its intrinsic thermoelectric performance is constrained by a relatively low Seebeck coefficient and an extremely high lattice thermal conductivity. In this investigation, we employ the alloying of Ge and AgSbTe2 to enhance the zT value of SnTe. The study found that Ge, Ag, and Sb can effectively enhance the Seebeck coefficient and power factor of SnTe by utilizing band convergence. At the same time, a multitude of point defects induce phonon scattering, consequently decreasing the lattice thermal conductivity of SnTe. Collectively, these synergistic effects result in Sn0.75Ge0.25Te-15% AgSbTe2 achieving its highest zT value of 1.28 at 823 K, with an average zT value of 0.77 between 400 and 823 K. Such high zT values of the SnTe-based thermoelectric material provide the potential for applications in high-performance solid-state thermoelectric devices.