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1.
Cell ; 186(16): 3400-3413.e20, 2023 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-37541197

RESUMEN

Approximately 15% of US adults have circulating levels of uric acid above its solubility limit, which is causally linked to the disease gout. In most mammals, uric acid elimination is facilitated by the enzyme uricase. However, human uricase is a pseudogene, having been inactivated early in hominid evolution. Though it has long been known that uric acid is eliminated in the gut, the role of the gut microbiota in hyperuricemia has not been studied. Here, we identify a widely distributed bacterial gene cluster that encodes a pathway for uric acid degradation. Stable isotope tracing demonstrates that gut bacteria metabolize uric acid to xanthine or short chain fatty acids. Ablation of the microbiota in uricase-deficient mice causes severe hyperuricemia, and anaerobe-targeted antibiotics increase the risk of gout in humans. These data reveal a role for the gut microbiota in uric acid excretion and highlight the potential for microbiome-targeted therapeutics in hyperuricemia.


Asunto(s)
Gota , Hominidae , Hiperuricemia , Adulto , Animales , Humanos , Ratones , Gota/genética , Gota/metabolismo , Hominidae/genética , Hiperuricemia/genética , Mamíferos/metabolismo , Urato Oxidasa/genética , Ácido Úrico/metabolismo , Evolución Molecular
2.
Cell ; 186(13): 2839-2852.e21, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37352836

RESUMEN

The gut microbiome is complex, raising questions about the role of individual strains in the community. Here, we address this question by constructing variants of a complex defined community in which we eliminate strains that occupy the bile acid 7α-dehydroxylation niche. Omitting Clostridium scindens (Cs) and Clostridium hylemonae (Ch) eliminates secondary bile acid production and reshapes the community in a highly specific manner: eight strains change in relative abundance by >100-fold. In single-strain dropout communities, Cs and Ch reach the same relative abundance and dehydroxylate bile acids to a similar extent. However, Clostridium sporogenes increases >1,000-fold in the ΔCs but not ΔCh dropout, reshaping the pool of microbiome-derived phenylalanine metabolites. Thus, strains that are functionally redundant within a niche can have widely varying impacts outside the niche, and a strain swap can ripple through the community in an unpredictable manner, resulting in a large impact on an unrelated community-level phenotype.


Asunto(s)
Microbioma Gastrointestinal , Ácidos y Sales Biliares , Clostridiales
3.
Cell ; 185(19): 3617-3636.e19, 2022 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-36070752

RESUMEN

Efforts to model the human gut microbiome in mice have led to important insights into the mechanisms of host-microbe interactions. However, the model communities studied to date have been defined or complex, but not both, limiting their utility. Here, we construct and characterize in vitro a defined community of 104 bacterial species composed of the most common taxa from the human gut microbiota (hCom1). We then used an iterative experimental process to fill open niches: germ-free mice were colonized with hCom1 and then challenged with a human fecal sample. We identified new species that engrafted following fecal challenge and added them to hCom1, yielding hCom2. In gnotobiotic mice, hCom2 exhibited increased stability to fecal challenge and robust colonization resistance against pathogenic Escherichia coli. Mice colonized by either hCom2 or a human fecal community are phenotypically similar, suggesting that this consortium will enable a mechanistic interrogation of species and genes on microbiome-associated phenotypes.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Animales , Bacterias/genética , Escherichia coli , Heces , Microbioma Gastrointestinal/genética , Vida Libre de Gérmenes , Humanos , Ratones
5.
Nature ; 621(7977): 162-170, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37587342

RESUMEN

Certain bacterial strains from the microbiome induce a potent, antigen-specific T cell response1-5. However, the specificity of microbiome-induced T cells has not been explored at the strain level across the gut community. Here, we colonize germ-free mice with complex defined communities (roughly 100 bacterial strains) and profile T cell responses to each strain. The pattern of responses suggests that many T cells in the gut repertoire recognize several bacterial strains from the community. We constructed T cell hybridomas from 92 T cell receptor (TCR) clonotypes; by screening every strain in the community against each hybridoma, we find that nearly all the bacteria-specific TCRs show a one-to-many TCR-to-strain relationship, including 13 abundant TCR clonotypes that each recognize 18 Firmicutes. By screening three pooled bacterial genomic libraries, we discover that these 13 clonotypes share a single target: a conserved substrate-binding protein from an ATP-binding cassette transport system. Peripheral regulatory T cells and T helper 17 cells specific for an epitope from this protein are abundant in community-colonized and specific pathogen-free mice. Our work reveals that T cell recognition of commensals is focused on widely conserved, highly expressed cell-surface antigens, opening the door to new therapeutic strategies in which colonist-specific immune responses are rationally altered or redirected.


Asunto(s)
Bacterias , Microbioma Gastrointestinal , Linfocitos T , Animales , Ratones , Antígenos de Superficie/inmunología , Bacterias/clasificación , Bacterias/inmunología , Firmicutes/inmunología , Microbioma Gastrointestinal/inmunología , Linfocitos T Reguladores/inmunología , Células Th17/inmunología , Linfocitos T/inmunología , Simbiosis/inmunología , Vida Libre de Gérmenes , Receptores de Antígenos de Linfocitos T/inmunología , Hibridomas/citología , Hibridomas/inmunología , Separación Celular
6.
Nature ; 617(7961): 581-591, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37165188

RESUMEN

The spatiotemporal structure of the human microbiome1,2, proteome3 and metabolome4,5 reflects and determines regional intestinal physiology and may have implications for disease6. Yet, little is known about the distribution of microorganisms, their environment and their biochemical activity in the gut because of reliance on stool samples and limited access to only some regions of the gut using endoscopy in fasting or sedated individuals7. To address these deficiencies, we developed an ingestible device that collects samples from multiple regions of the human intestinal tract during normal digestion. Collection of 240 intestinal samples from 15 healthy individuals using the device and subsequent multi-omics analyses identified significant differences between bacteria, phages, host proteins and metabolites in the intestines versus stool. Certain microbial taxa were differentially enriched and prophage induction was more prevalent in the intestines than in stool. The host proteome and bile acid profiles varied along the intestines and were highly distinct from those of stool. Correlations between gradients in bile acid concentrations and microbial abundance predicted species that altered the bile acid pool through deconjugation. Furthermore, microbially conjugated bile acid concentrations exhibited amino acid-dependent trends that were not apparent in stool. Overall, non-invasive, longitudinal profiling of microorganisms, proteins and bile acids along the intestinal tract under physiological conditions can help elucidate the roles of the gut microbiome and metabolome in human physiology and disease.


Asunto(s)
Ácidos y Sales Biliares , Microbioma Gastrointestinal , Intestinos , Metaboloma , Proteoma , Humanos , Ácidos y Sales Biliares/metabolismo , Microbioma Gastrointestinal/fisiología , Proteoma/metabolismo , Bacterias/clasificación , Bacterias/aislamiento & purificación , Bacteriófagos/aislamiento & purificación , Bacteriófagos/fisiología , Heces/química , Heces/microbiología , Heces/virología , Intestinos/química , Intestinos/metabolismo , Intestinos/microbiología , Intestinos/fisiología , Intestinos/virología , Digestión/fisiología
7.
BMC Infect Dis ; 24(1): 656, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38956526

RESUMEN

OBJECTIVE: To investigate risk factors associated with long-term mortality in patients with stage II and III tuberculous meningitis (TBM). METHODS: This retrospective analysis examined patients who were first diagnosed with stage II and III TBM at West China Hospital of Sichuan University between January 1, 2018 and October 1, 2019. Patients were followed via telephone and categorized into survival and mortality groups based on 4-year outcomes. Multivariate logistic regression identified independent risk factors for long-term mortality in stage II and III TBM. RESULTS: In total, 178 patients were included, comprising 108 (60.7%) males and 36 (20.2%) non-survivors. Mean age was 36 ± 17 years. Compared to survivors, non-survivors demonstrated significantly higher age, heart rate, diastolic blood pressure, blood glucose, rates of headache, neurological deficits, cognitive dysfunction, impaired consciousness, hydrocephalus, and basal meningeal inflammation. This group also exhibited significantly lower Glasgow Coma Scale (GCS) scores, blood potassium, albumin, and cerebrospinal fluid chloride. Multivariate analysis revealed age (OR 1.042; 95% CI 1.015-1.070; P = 0.002), GCS score (OR 0.693; 95% CI 0.589-0.814; P < 0.001), neurological deficits (OR 5.204; 95% CI 2.056-13.174; P < 0.001), and hydrocephalus (OR 2.680; 95% CI 1.081-6.643; P = 0.033) as independent mortality risk factors. The ROC curve area under age was 0.613 (95% CI 0.506-0.720; P = 0.036) and 0.721 (95% CI 0.615-0.826; P < 0.001) under GCS score. CONCLUSION: Advanced age, reduced GCS scores, neurological deficits, and hydrocephalus were identified as independent risk factors for mortality in stage II and III TBM patients.


Asunto(s)
Tuberculosis Meníngea , Humanos , Masculino , Tuberculosis Meníngea/mortalidad , Tuberculosis Meníngea/complicaciones , Femenino , Adulto , Factores de Riesgo , Estudios Retrospectivos , Persona de Mediana Edad , Adulto Joven , China/epidemiología , Escala de Coma de Glasgow , Adolescente
8.
Mol Pharmacol ; 100(2): 113-118, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34074676

RESUMEN

Acid-sensing ion channels (ASICs) are widely expressed in the nervous system. The intracellular C terminus of ASIC1a has many sites involved in regulating its expression and the opening mechanism, but the role of the intracellular N-terminal domain is poorly understood. Here, we explored the correlation of ASIC1a intracellular N terminus with membrane expression and gate opening. We modified the N-terminal structure of ASICs by deletion/truncation/mutation strategies and transfected the recombinant plasmids into CHO cells. Protein expression was analyzed with immunofluorescence, Western blots, and patch-clamp experiments. Deleting the entire N terminus decreased the membrane expression of channel proteins, and ion channel opening was lost. Deleting sections of the N terminus also decreased membrane expression and suggested that all areas were significant, with no single or group of amino acid residues playing a decisive role in regulating ASIC1a membrane expression. In terms of gate opening, five amino acid (AA) residues from AA 16 to AA 20 participated in gate opening, and isoleucine at AA 18 was the most important. The whole N terminus of ASICs participates in the membrane expression of ASIC1a, and five amino acid residues (AA 16-20) are involved in the gate opening mechanism. SIGNIFICANCE STATEMENT: The whole N terminus of ASICs participates in the membrane expression of ASIC1a, and five amino acid resi-dues (amino acid 16-20) are involved in the gate opening mechanism.


Asunto(s)
Canales Iónicos Sensibles al Ácido/química , Canales Iónicos Sensibles al Ácido/metabolismo , Membrana Celular/metabolismo , Mutación , Canales Iónicos Sensibles al Ácido/genética , Secuencias de Aminoácidos , Animales , Células CHO , Cricetulus , Dominios Proteicos , Transfección
9.
Bioinformatics ; 35(5): 760-768, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30816928

RESUMEN

MOTIVATION: Whole genome shotgun based next-generation transcriptomics and metagenomics studies often generate 100-1000 GB sequence data derived from tens of thousands of different genes or microbial species. Assembly of these data sets requires tradeoffs between scalability and accuracy. Current assembly methods optimized for scalability often sacrifice accuracy and vice versa. An ideal solution would both scale and produce optimal accuracy for individual genes or genomes. RESULTS: Here we describe an Apache Spark-based scalable sequence clustering application, SparkReadClust (SpaRC), that partitions reads based on their molecule of origin to enable downstream assembly optimization. SpaRC produces high clustering performance on transcriptomes and metagenomes from both short and long read sequencing technologies. It achieves near-linear scalability with input data size and number of compute nodes. SpaRC can run on both cloud computing and HPC environments without modification while delivering similar performance. Our results demonstrate that SpaRC provides a scalable solution for clustering billions of reads from next-generation sequencing experiments, and Apache Spark represents a cost-effective solution with rapid development/deployment cycles for similar large-scale sequence data analysis problems. AVAILABILITY AND IMPLEMENTATION: https://bitbucket.org/berkeleylab/jgi-sparc.


Asunto(s)
Algoritmos , Programas Informáticos , Análisis por Conglomerados , Secuenciación de Nucleótidos de Alto Rendimiento , Metagenómica , Análisis de Secuencia de ADN
10.
Cardiovasc Drugs Ther ; 34(1): 25-39, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32034643

RESUMEN

PURPOSE: Atherosclerosis is a narrowing of the arteries caused by plaque buildup. MicroRNAs (miRNAs) have been proposed to participate in the pathogenesis of atherosclerosis. Here, we aimed to investigate miR-205-5p's role in promoting atherosclerotic progression. METHODS: Knock-in (KI) mice with human/murine miR-205-5p within the murine host gene for miR-205 (MIR205HG) were crossed with apolipoprotein E knockout (Apoe-/-) mice. This miR-205KI Apoe-/- murine model was employed to study the impact of miR-205-5p in Apoe-/- mice susceptible to atherosclerotic plaque formation. RESULTS: miR-205KI Apoe-/-mice developed larger, more unstable plaques relative to their Apoe-/- counterparts (0.45 vs. 0.26 mm2, P < 0.001). miR-205KI Apoe-/- mice exhibited lower serum levels of high-density lipoprotein cholesterol (HDL-C) (5.18 vs. 19.31 mg/dL, P < 0.001) and triglycerides (32.79 vs. 156.76 mg/dL, P < 0.001) with system-wide reversal of cholesterol transport. Macrophages derived from miR-205KI Apoe-/- mice exhibited ~ 20% lowered cholesterol efflux capability with enhanced pro-inflammatory gene expression through lipid raft formation. Bone marrow transplantation demonstrated that bone marrow (BM) donor cells with miR-205-5pKI simulated plaque formation independent of the recipients' miR-205-5p status. CONCLUSIONS: miR-205-5p encourages unstable atherogenesis in vivo. miR-205-5p also adversely influences lipid metabolism and promotes a pro-inflammatory macrophage phenotype. Our findings advocate miR-205-5p as a potential therapeutic target for combating unstable atherogenesis.


Asunto(s)
Aorta/metabolismo , Enfermedades de la Aorta/metabolismo , Aterosclerosis/metabolismo , MicroARNs/metabolismo , Placa Aterosclerótica , Animales , Aorta/patología , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/patología , Apoptosis , Aterosclerosis/genética , Aterosclerosis/patología , Trasplante de Médula Ósea , Estudios de Casos y Controles , HDL-Colesterol/sangre , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Macrófagos/metabolismo , Macrófagos/patología , Microdominios de Membrana/metabolismo , Microdominios de Membrana/patología , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , MicroARNs/genética , Fenotipo , Rotura Espontánea , Células THP-1 , Triglicéridos/sangre
11.
BMC Health Serv Res ; 20(1): 1007, 2020 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-33148229

RESUMEN

BACKGROUND: The COVID-19 has been a pandemic around the world, which affirmatively brought mental health problems to medical staff. We aimed to investigate the prevalence of anxiety in Chinese medical staff and examine the mediation effects of coping styles on the relationship between social support and anxiety. METHODS: A cross-sectional study via internet survey was conducted from 15 March to 30 March, 2020. The social demographic data, Self-rated Anxiety Scale, Social Support Rate Scale and Trait Coping Style Scale were collected. Pearson correlation and a structural equation model were performed to examine the relationships of these variables. The bootstrap analysis was conducted to evaluate the mediation effects. RESULTS: A total of 453 medical staff participated in this study. The mean score of SAS was 46.1 (SD = 10.4). Up to 40.8% of the participants had anxiety symptoms. The participants lived with family members had lower SAS score (45.1 ± 9.8 vs 49.6 ± 11.8). Social support was negatively associated with anxiety, mediated by positive coping and negative coping partially significantly with an effect size of - 0.183. CONCLUSIONS: Chinese medical staff had a high level of anxiety during the COVID-19 pandemic. Coping styles had effects on the association between social support and anxiety. Sufficient social support and training on positive coping skills may reduce anxiety in medical staff.


Asunto(s)
Adaptación Psicológica , Ansiedad/epidemiología , Infecciones por Coronavirus/epidemiología , Cuerpo Médico/psicología , Pandemias , Neumonía Viral/epidemiología , Apoyo Social , Adolescente , Adulto , COVID-19 , China/epidemiología , Estudios Transversales , Femenino , Humanos , Masculino , Cuerpo Médico/estadística & datos numéricos , Persona de Mediana Edad , Prevalencia , Encuestas y Cuestionarios , Adulto Joven
12.
J Nurs Manag ; 27(2): 433-441, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30443947

RESUMEN

AIMS: To collect information about the current status of community nurses in China and explore the roles and activities that they perform in their daily community setting. BACKGROUND: Community health services are central to efforts to improve public health in China. Clarifying who performs which community nursing services can help assess the contributions of community nursing and guide future practices. However, specific information is limited in China. METHODS: A descriptive, cross-sectional survey was conducted from March to November 2014. Information was collected on demographics, work roles, and activities of community nurses. RESULTS: Most community nurses in our survey were young with a low educational level. Their daily routine most frequently involved immunization and basic medical services, while their main roles were caregiver, educator, organiser and manager. CONCLUSION: Although community nurses cover nearly all areas of service that the national government requires, some roles and their associated activities are neglected. The quantity and quality of community nurses may be hindering their ability to fulfill all roles and activities envisioned by the national government. IMPLICATIONS FOR NURSING MANAGEMENT: Further training should be provided to increase the ability of community nurses to perform frequent functions as well as activities that are currently neglected.


Asunto(s)
Rol de la Enfermera/psicología , Enfermeros de Salud Comunitaria/psicología , Adulto , China , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermeros de Salud Comunitaria/estadística & datos numéricos , Encuestas y Cuestionarios
13.
J Affect Disord ; 347: 500-508, 2024 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-38065477

RESUMEN

BACKGROUND: It is unclear about the mutual impact of COVID-19 related psychological stress and infection on mental health of adolescent and youth students. This study aimed to explore the mutual impact of COVID-19 related psychological stress and infection on mental health problems among students. METHODS: This study was conducted from December 14, 2022 to February 28, 2023 in Sichuan, China. Patient Health Questionnaire-9, Generalized Anxiety Disorder-7, PTSD Checklist for DSM-5, Insomnia Severity Index, and Internet Addiction Test were used. Participants were grouped by COVID-19 infection and psychological stress level. The differences among groups were compared, and logistic regression analysis was used to investigate risk factors for depression, anxiety, PTSD and insomnia among groups. RESULTS: Of 90,118 participants, 82,873 (92.0 %) finished the questionnaires and were included in the study. Of 82,873 participants, 33,314 (40.2 %) reported to be infected with COVID-19. Participants had depression symptoms (38.1 %), anxiety symptoms (31.8 %), PTSD (33.9 %), insomnia (34.0 %), and internet addiction (60.3 %). Compared with participants uninfected with low psychological stress level, the risk for symptoms of depression, anxiety, PTSD and insomnia increased by 9.6 %, 12.3 %, 6.6 %, and 12.0 % in participants infected with low psychological stress level (p < 0.001), 106.8 %, 125.9 %, 125.2 %, and 95.7 % in participants uninfected with high psychological stress level (p < 0.001), and 147.3 %, 161.1 %, 158.7 %, and 141.0 % in participants infected with high psychological stress level (p < 0.001). LIMITATION: This study is a cross-sectional design, and no causal associations should be inferred. Infection status was based on self-report of participants with infectious symptoms. CONCLUSION: COVID-19 related psychological stress and infection per se have mutually overlapping impacts on mental health problems among students. Further health policies and psychosocial interventions should be developed to reduce mutually overlapping impact and improve the long-term mental health among students.


Asunto(s)
COVID-19 , Trastornos del Inicio y del Mantenimiento del Sueño , Adolescente , Humanos , COVID-19/epidemiología , Salud Mental , SARS-CoV-2 , Pandemias , Trastornos del Inicio y del Mantenimiento del Sueño/epidemiología , Estudios Transversales , Ansiedad/diagnóstico , China/epidemiología , Depresión/diagnóstico
14.
bioRxiv ; 2024 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-38328052

RESUMEN

The ubiquitous skin colonist Staphylococcus epidermidis elicits a CD8 + T cell response pre-emptively, in the absence of an infection 1 . However, the scope and purpose of this anti-commensal immune program are not well defined, limiting our ability to harness it therapeutically. Here, we show that this colonist also induces a potent, durable, and specific antibody response that is conserved in humans and non-human primates. A series of S. epidermidis cell-wall mutants revealed that the cell surface protein Aap is a predominant target. By colonizing mice with a strain of S. epidermidis in which the parallel ß-helix domain of Aap is replaced by tetanus toxin fragment C, we elicit a potent neutralizing antibody response that protects mice against a lethal challenge. A similar strain of S. epidermidis expressing an Aap-SpyCatcher chimera can be conjugated with recombinant immunogens; the resulting labeled commensal elicits high titers of antibody under conditions of physiologic colonization, including a robust IgA response in the nasal mucosa. Thus, immunity to a common skin colonist involves a coordinated T and B cell response, the latter of which can be redirected against pathogens as a novel form of topical vaccination.

15.
Psychiatry Investig ; 20(3): 220-227, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36990665

RESUMEN

OBJECTIVE: This study aimed to translate the English version of the Perceived Competence Scale for Disaster Mental Health Workforce (PCS-DMHW) into Chinese, and to test its reliability and validity in Chinese mental health workers. METHODS: With the consent of Professor Choi, Keimyung University, Korea, and the authorization of the scale, the English version of PCS-DMHW was translated, retranslated and culturally debugged to form the Chinese version of PCS-DMHW. The general information questionnaire and the Chinese version of PCS-DMHW scale were used to investigate 706 mental health workforce from 9 tertiary hospitals in Sichuan province in China from March 24, 2020 to April 14, 2020. The Cronbach's α coefficient was used to evaluate the internal consistency reliability of the scale, and the test-retest correlation coefficient r was used to evaluate the test-retest reliability of the scale. The content validity indexes (CVI) and exploratory factor analysis (EFA) was used separately for evaluating the content validity and structure validity of the scale. RESULTS: The Cronbach's α coefficient of the Chinese version of PCS-DMHW total scale, individual competences and organizational competences subscale was 0.978, 0.956, and 0.964, respectively. The test-retest reliability of the total scale, individual competences and organizational competences subscale was 0.949, 0.932 and 0.927, respectively. The item-level CVI of all scale were ranged from 0.833-1.000, the scale-level CVI (S-CVI)/universal agreement of the total scale, individual competences and organizational competences subscale was 0.833, 0.875, and 0.857, respectively, and the S-CVI/average was 0.972, 0.979, and 0.976, respectively. EFA showed that two principal components were extracted from the subscale of individual competences and organizational competences. CONCLUSION: The Chinese version of PCS-DMHW has good reliability and validity, and can be widely used in China.

16.
Materials (Basel) ; 16(7)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37048950

RESUMEN

Modified polyurethane concrete (MPUC) is a new material for steel deck pavements. In service, the pavement is often cracked due to excessive tensile stress caused by temperature changes. In order to study the tensile properties of MPUC in the diurnal temperature range of steel decks, uniaxial tensile tests of MPUC were carried out at five temperatures. Three kinds of specimens and a novel fixture were designed and fabricated to compare the results of four different tensile test methods. The deformation of the specimen was collected synchronously by two methods: pasting strain gauge and digital image correlation (DIC) technique. Based on the experiment, the tensile mechanical properties, failure modes, and constitutive relations of MPUC were studied under the effect of temperature. The research results show that the novel fixture can avoid stress concentration. By observing the fracture surface of the specimens, the bonding performance is great between the binder and the aggregate at different temperatures. The tensile strength and elastic modulus of MPUC decrease with increasing temperatures, while the fracture strain, and fracture energy increase with increasing temperatures. The formulas of temperature-dependent tensile strength, fracture strain, and elastic modulus of MPUC were established, and the constitutive relationship of MPUC is further constructed in the rising stage under uniaxial tension. The calculation results show good agreement with experimental ones.

17.
Nat Commun ; 14(1): 3510, 2023 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-37316519

RESUMEN

Microbial community function depends on both taxonomic composition and spatial organization. While composition of the human gut microbiome has been deeply characterized, less is known about the organization of microbes between regions such as lumen and mucosa and the microbial genes regulating this organization. Using a defined 117 strain community for which we generate high-quality genome assemblies, we model mucosa/lumen organization with in vitro cultures incorporating mucin hydrogel carriers as surfaces for bacterial attachment. Metagenomic tracking of carrier cultures reveals increased diversity and strain-specific spatial organization, with distinct strains enriched on carriers versus liquid supernatant, mirroring mucosa/lumen enrichment in vivo. A comprehensive search for microbial genes associated with this spatial organization identifies candidates with known adhesion-related functions, as well as novel links. These findings demonstrate that carrier cultures of defined communities effectively recapitulate fundamental aspects of gut spatial organization, enabling identification of key microbial strains and genes.


Asunto(s)
Microbioma Gastrointestinal , Microbiota , Humanos , Microbioma Gastrointestinal/genética , Hidrogeles , Metagenoma , Microbiota/genética , Mucinas
18.
Int J Soc Psychiatry ; 69(4): 1024-1032, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36708508

RESUMEN

BACKGROUND: Although stigma and caregiving burden are important in relation to mental health recovery, few studies have been conducted on affiliate stigma and caregiving burden among family caregivers of persons with schizophrenia (FCPWS) in rural China. AIMS: This study aimed to examine the severity level of affiliate stigma and caregiving burden, and identify the correlates among FCPWS in rural China. METHODS: A mental health survey was conducted (N = 253 FCPWS) in Xinjin county, Sichuan province, China. Affiliate Self-Stigma Scale and Zarit Burden Interview Short Form were used. The regression analysis was performed to explore the correlates of stigma and burden. RESULTS: Most FCPWS reported experiencing high and severe level of affiliate stigma (78.66%) and caregiving burden (95.26%). Family caregivers who were middle aged, unemployed, with high caregiving burden and low quality of life (QoL), showed more severe affiliate stigma. Family caregivers who were female, older, with low income, high affiliate stigma and low QoL, experienced greater caregiving burden. CONCLUSIONS: The large majority of FCPWS in rural China experienced severe affiliate stigma, caregiving burden and poor QoL. It is crucial to develop culture-specific anti-stigma interventions to reduce caregivers' stigma and caregiving burden, and improve QoL. Specific risk factors of family caregivers' affiliate stigma and caregiving burden should be considered for development of health policy and community-based mental health services.


Asunto(s)
Cuidadores , Esquizofrenia , Persona de Mediana Edad , Humanos , Femenino , Masculino , Cuidadores/psicología , Calidad de Vida/psicología , Familia/psicología , Estigma Social , China
19.
Front Psychiatry ; 14: 1243619, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37953935

RESUMEN

Background: Internet addiction (IA) among students, worsened by Coronavirus disease 2019 (COVID-19) pandemic, has become a social problem with the digitalization of school learning and many aspects of daily life. However, few studies on IA have been conducted among students after the lifting of COVID-19 restrictions in China. Method: This large-sample, cross-sectional, online survey was conducted to explore the characteristics of IA and the association among IA, academic satisfaction, and mental health problems from December 14, 2022 to February 28, 2023 in Sichuan, China. All participants (N = 22,605) were students in colleges and universities, recruited via their teachers and professors. Results: Of all the participants, 14,921 (66.0%) participants had IA. Participants with IA were more likely to have depression symptom, anxiety symptom, insomnia, and lifetime suicidal ideation. In addition, participants with severe IA had significantly higher rates of mental health problems (e.g., depression, anxiety, insomnia, and suicidal ideation) than those with mild IA. A significant IA-by-academic satisfactory-interaction on mental health was identified: participants with higher level of IA showed particularly severe symptom of depression, anxiety and insomnia when affected by low satisfactory of academy (p < 0.001). Conclusion: This study reveals that IA has a significantly negative impact on mental health among college students after the lifting of COVID-19 restrictions in China. IA and academic satisfaction have interactive impacts on mental health problems among students. Further educational and health policies and psychosocial interventions should be developed to reduce IA and enhance academic satisfaction for improving students' mental health.

20.
Front Psychiatry ; 14: 1248541, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37645634

RESUMEN

Background: Although the COVID-19 pandemic has greatly changed the way students studied, it is still unknown about the impact of the COVID-19 pandemic on students' academic performance and mental health. Objective: To explore the academic performance and mental health status of middle and high school students after the lifting of COVID-19 restrictions in China. Methods: An online survey was conducted in Sichuan province, China from Dec 14, 2022 to Feb 28, 2023. All participants were students in middle and high schools, recruited via their teachers. The general information, COVID-19-related information, and academic performance were collected. The Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and Internet Addiction Test (IAT) were used to assess the mental health problems. Results: Of 60,268 participants, 36,247 (60.2%) middle and high school students reported that their studies were affected by the COVID-19 pandemic, and 24,864 (41.2%) reported that their academic performance had worsened. The prevalence of depression and anxiety symptoms was 38.4 and 32.7%, respectively. There was a significant association between academic performance change and mental health problems. The logistic regression analysis showed that improved academic performance was a protective factor for depression, and declined academic performance was a risk factor for depression and anxiety. Being COVID-19 infected, family members being infected, with quarantine experience, and with COVID-19-related stigma were risk factors for depression and anxiety. Conclusion: Academic studies and mental health status of middle and high school students in Sichuan, China have been negatively impacted by the COVID-19 pandemic, even after the lifting of COVID-19 restrictions. Students' academic performance, academic concerns, and mental health status should be considered for educational policymakers and institutions to improve students' academic studies and mental well-being.

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