RÉSUMÉ
Diabetes mellitus (DM), an important public health problem, aggravates the global economic burden. Diabetic encephalopathy (DE) is a serious complication of DM in the central nervous system. Metformin has been proven to improve DE. However, the mechanism is still unclear. In this study, the db/db mice, a common model used for DE, were employed to explore and study the neuroprotective effect of metformin and related mechanisms. Behavioral tests indicated that metformin (100 or 200 mg/kg/day) could significantly improve the learning and memory abilities of db/db mice. The outcomes from the oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) demonstrate that metformin effectively modulates glucose and insulin signaling pathways in db/db mice. The results of body weight and blood lipid panel (total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol) show that metformin promotes the level of lipid metabolism in db/db mice. Furthermore, data from oxidative stress assays, which measured levels of malondialdehyde, superoxide dismutase, catalase, and glutathione peroxidase, suggest that metformin suppresses oxidative stress-induced brain damage in db/db mice. In addition, western blot, Nissl staining, and immunofluorescence results showed that metformin increased the expressions of nerve growth factor and postsynaptic density 95 and repaired neuronal structural damage. For the mechanism study, metformin activated SIRT1 and inhibited the expression of NLRP3 inflammasome (NLRP3, ASC, caspase-1, IL-1ß, and IL-18) and inflammatory cytokines (TNFα and IL-6). In conclusion, metformin could ameliorate cognitive dysfunction through the SIRT1/NLRP3 pathway, which might be a promising mechanism for DE treatment.
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The lack of systematic approaches and analyses to identify, quantify, and manage the biotic transport of microplastics (MPs) along cross-ecosystem landscapes prevents the current goals of sustainable environmental development from being met. This Perspective proposes a meta-ecosystem framework, which considers organismal and resource flows among ecosystems to shed light on the research and management challenges related to both abiotic and biotic MP transport at landscape levels. We discuss MP transport pathways through species movements and trophic transfers among ecosystems and sub-ecosystems, and highlight these pathways in the mitigation of MP pollution. The integration of biotic pathways across landscapes prioritizes management actions for MP transport using diverse approaches such as wastewater treatment and plastic removal policies to mitigate contamination. In addition, our framework emphasizes the potential sink enhancement of MPs through habitat conservation and enhancement of riparian vegetation. By considering the mechanisms of meta-ecosystem dynamics through the processes of biotic dispersal, accumulation, and the ultimate fate of MPs, advances in the environmental impact assessment and management of MP production can proceed more effectively.
Sujet(s)
Écosystème , Microplastiques , Surveillance de l'environnement , Matières plastiquesRÉSUMÉ
Global ecosystems are facing anthropogenic threats that affect their ecological functions and biodiversity. However, we still lack an understanding of how biodiversity can mediate the responses of ecosystems or communities to human disturbance across spatial gradients. Here, we examined how existing, spatial patterns of biodiversity influence the ecological effects of small hydropower plants (SHPs) on macroinvertebrates in river ecosystems. This study found that levels of biodiversity (e.g., number of species) can influence the degrees of its alterations by SHPs occurring along elevational gradients. The results of the study reveal that the construction of SHPs has various effects on biodiversity. For example, low-altitude areas with low biodiversity (species richness less than 12) showed a small increase in biodiversity compared to high-altitude areas (species richness more than 12) under SHP disturbances. The increases in the effective habitat area of the river segment could be a driver of the enhanced biodiversity in response to SHP effects. Changes in the numerically dominant species contributed to the overall level of community variation from disturbances. Location-specific strategies may mitigate the effects of SHPs and perhaps other disturbances.
Sujet(s)
Écosystème , Rivières , Humains , Biodiversité , AltitudeRÉSUMÉ
Objectives: We aimed to evaluate the indeterminate rate of interferon gamma release assays (IGRAs) in the detection of latent tuberculosis infection (LTBI). Methods: On 15 November 2022, we searched the PubMed® (National Library of Medicine, Bethesda, MD, USA), Embase® (Elsevier, Amsterdam, the Netherlands), and Cochrane Library databases in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two investigators independently extracted the study data and assessed their quality using a modified quality assessment of diagnostic accuracy studies (i.e., QUADAS-2) tool. A random-effects model was used to calculate pooled results. Results: We included 403 studies involving 486,886 individuals and found that the pooled indeterminate rate was 3.9% (95% CI 3.5%-4.2%). The pooled indeterminate rate for QuantiFERON®-TB (QFT) was similar to that for T-SPOT®.TB (T-SPOT) [odds ratio (OR) = 0.88, 95% CI 0.59-1.32]; however, the indeterminate rate for a new generation of QFT (QFT-plus) was lower than that of T-SPOT (OR = 0.24, 95% CI 0.16-0.35). The indeterminate rate in the immunocompromised population was significantly higher than that in healthy controls (OR = 3.51, 95% CI 2.11-5.82), and it increased with the reduction of CD4+ cell count in HIV-positive patients. Children's pooled indeterminate rates (OR = 2.56, 95% CI 1.79-3.57) were significantly higher than those of adults, and the rates increased as the children's age decreased. Conclusion: On average, 1 in 26 tests yields indeterminate IGRA results in LTBI screening. The use of advanced versions of the QuantiFERON-TB assay (QFT-plus), may potentially reduce the occurrence of an indeterminate result. Our study emphasizes the high risk of immunosuppression and young age in relation to indeterminate IGRA, which should receive more attention in the management of LTBI. Systematic review registration: PROSPERO https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42020211363, CRD42020211363.
Sujet(s)
Séropositivité VIH , Tuberculose latente , États-Unis , Enfant , Adulte , Humains , Tests de libération d'interféron-gamma/méthodes , Tuberculose latente/diagnostic , Tuberculose latente/épidémiologie , Dépistage de masse , Sujet immunodépriméRÉSUMÉ
Patients with ischemia with non-obstructive coronary arteries (INOCA) have an increased risk of adverse cardiovascular events in the future, which is widespread but underdiagnosed. The purpose of this study is to explore the application value of adenosine stress myocardial contrast echocardiography (ASMCE) in INOCA disease, so that clinicians can early identify and intervene patients with left ventricular function subclinical impairment in INOCA. We enrolled 118 patients with INOCA by ASMCE and invasive coronary angiography (ICA), 97 of whom had complete data. The study population was divided into two subgroups depending on coronary flow velocity reserve (CFVR): impaired CFVR group (n = 34) and normal CFVR group (n = 63). Global longitudinal strain endocardial myocardial (GLSendo), mid-myocardial (GLSmid) and epicardial myocardial (GLSepi) increased after stress in both groups; transmural strain, wall motion scored index (WMSI) and myocardial perfusion scored index (MPSI) increased and FORCE decreased in impaired CFVR group after stress, but there was no difference in normal group before and after stress. There was no significant difference in left ventricular myocardial mechanical parameters, including ΔGLSendo, ΔGLSmid, ΔGLSepi, GLSendo-epi Reserve, Δpeak strain dispersion (PSD), PSD Reserve between the two groups, but ΔEF, strain reserve and left ventricular contractile reserve (LVCR) in the impaired CFVR group were lower than those in the normal CFVR group, while ΔWMSI and ΔMPSI were increased. CFVR can be a clinically valuable indicator in the ASMCE diagnosis of patients with microvascular angina pectoris in INOCA. In the evaluation of left ventricular function in INOCA patients, attention should be paid not only to myocardial deformation, but also to the dynamic changes of LVCR and myocardial perfusion during peak hyperemia.
Sujet(s)
Vaisseaux coronaires , Dysfonction ventriculaire gauche , Humains , Vaisseaux coronaires/imagerie diagnostique , Fonction ventriculaire gauche , Adénosine , Valeur prédictive des tests , Échocardiographie , Échocardiographie de stress , Vitesse du flux sanguin , Circulation coronarienneRÉSUMÉ
OBJECTIVE: To compare the positive rates of IGRA and TST in detection of LTBI. METHODS: We searched PubMed, Embase, and the Cochrane Library on March 12, 2022. A random-effects model was used to calculate pooled results. RESULTS: We included 458 head-to-head studies. Compared with immunocompetent controls, TST positive rate in immunosuppressed population decreased more than IGRA positive rate (OR 0.36 [95% CI: 0.31 to 0.41] versus 0.53 [0.46 to 0.61]). In immunocompetent BCG-vaccinated individuals, IGRA positive rate in low-TB burden areas was significantly lower than TST positive rate, but the difference was decreased in high-TB burden areas (OR 0.75 [0.60 to 0.94]). Additionally, IGRA positive rate was equal to that of TST in the elderly (OR 0.98 [0.66 to 1.46]). CONCLUSION: TST is more susceptible to immunosuppression than IGRA. The effect of BCG on TST might be weakened in high-TB burden areas, and TST response waned in the elderly. REVIEW REGISTRATION: PROSPERO CRD42020180163.
Sujet(s)
Tests de libération d'interféron-gamma , Tuberculose latente , Humains , Sujet âgé , Tests de libération d'interféron-gamma/méthodes , Test tuberculinique/méthodes , Tuberculose latente/diagnostic , Vaccin BCG , Sujet immunodépriméRÉSUMÉ
Background: Oxidative stress-induced neurotoxicity plays a key role in Alzheimer's disease (AD). 11,12-Diacetyl-carnosol (NO.20), an acetylated derivative of carnosol extracted from rosemary, displays a high antioxidative effect in vitro. Purpose: We investigated the neuroprotective effect of NO.20 on H2O2-induced neurotoxicity in human neuroblastoma SH-SY5Y cells and its possible mechanism. Results: We found that NO.20 pretreatment (1 µM for 1 h) had cytoprotective effects and weakened H2O2-induced damage in SH-SY5Y cells by reducing viability loss, apoptotic rate, and reactive oxygen species production. In addition, NO.20 inhibited H2O2-induced mitochondrial dysfunctions: it alleviated mitochondrial membrane potential loss and cytochrome c release, decreased the Bax/Bcl-2 ratio, and reduced caspase-3 expression. NO.20 also downregulated malondialdehyde and upregulated glutathione. Furthermore, NO.20 pretreatment caused the nuclear translocation of the transcription factor NF-E2-related factor 2 (Nrf2), increasing heme oxygenase-1 (HO-1) expression in SH-SY5Y cells. Notably, we found that silencing Nrf2 using small interfering RNA (siRNA) suppressed the NO.20-induced HO-1 expression and abolished the neuroprotective effect of NO.20. Conclusion: These results demonstrate that NO.20 protects SH-SY5Y cells from H2O2-induced neurotoxicity by activating the Nrf2/HO-1 pathway. Thus, the neuroprotective and antioxidative stress effects of NO.20 may make it a promising neuroprotective compound for AD treatment.
RÉSUMÉ
Spatial biodiversity is a key issue in biogeography for the explorations of biological origin and diversification. However, seldom studies have addressed the temporal changes in spatial patterns of biodiversity. We explored the taxonomic and functional diversities of riverine macroinvertebrates in central China, with the elevational gradient, in different seasons in a normal climate year (i.e., no extreme anomalies in the annual precipitation or average annual temperature). The air temperature and streamflow discharge were decreased monotonically with the increase of elevation both in the dry and wet seasons. In addition, the total nitrogen had no significant change with the increase of elevational gradient in the dry season but showed a monotonically decreasing pattern in the wet season. The total phosphorus showed a monotonically decreasing pattern with the elevational gradient in the dry season but had no significant change in the wet season. The spatial pattern of taxonomic diversity of macroinvertebrates along the elevational gradient showed complex patterns, but the functional diversity had either the unimodal or monotonically decreasing pattern. In addition, the functional diversity with the elevational gradient had similar patterns between the dry and wet seasons. Further analysis of the elevational pattern in different seasons is an important basis for understanding the status quo of functional diversity and formulating countermeasures for biodiversity conservation.
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BACKGROUND: Use of an interferon-γ (IFN-γ) release assay or tuberculin skin test for detection and management of latent tuberculosis infection is controversial. For both types of test, we assessed their predictive value for the progression of latent infection to active tuberculosis disease, the targeting value of preventive treatment, and the necessity of dual testing. METHODS: In this systematic review and meta-analysis, we searched PubMed, Embase, Web of Science, and the Cochrane Library, with no start date or language restrictions, on Oct 18, 2019, using the keywords ("latent tuberculosis" OR "latent tuberculosis infection" OR "LTBI") AND ("interferon gamma release assays" OR "Interferon-gamma Release Test" OR "IGRA" OR "QuantiFERON®-TB in tube" OR "QFT" OR "T-SPOT.TB") AND ("tuberculin skin test" OR "tuberculin test" OR "Mantoux test" OR "TST"). We included articles that used a cohort study design; included information that individuals with latent tuberculosis infection detected by IFN-γ release assay, tuberculin skin test, or both, progressed to active tuberculosis; reported information about treatment; and were limited to high-risk populations. We excluded studies that included patients with active or suspected tuberculosis at baseline, evaluated a non-commercial IFN-γ release assay, and had follow-up of less than 1 year. We extracted study details (study design, population investigated, tests used, follow-up period) and the number of individuals observed at baseline, who progressed to active tuberculosis, and who were treated. We then calculated the pooled risk ratio (RR) for disease progression, positive predictive value (PPV), and negative predictive value (NPV) of IFN-γ release assay versus tuberculin skin test. FINDINGS: We identified 1823 potentially eligible studies after exclusion of duplicates, of which 256 were eligible for full-text screening. From this screening, 40 studies (50â592 individuals in 41 cohorts) were identified as eligible and included in our meta-analysis. Pooled RR for the rate of disease progression in untreated individuals who were positive by IFN-γ release assay versus those were negative was 9·35 (95% CI 6·48-13·49) compared with 4·24 (3·30-5·46) for tuberculin skin test. Pooled PPV for IFN-γ release assay was 4·5% (95% CI 3·3-5·8) compared with 2·3% (1·5-3·1) for tuberculin skin test. Pooled NPV for IFN-γ release assay was 99·7% (99·5-99·8) compared with 99·3% (99·0-99·5) for tuberculin skin test. Pooled RR for rates of disease progression in individuals positive by IFN-γ release assay who were untreated versus those who were treated was 3·09 (95% CI 2·08-4·60) compared with 1·11 (0·69-1·79) for the same populations who were positive by tuberculin skin test. Pooled proportion of disease progression for individuals who were positive by IFN-γ release assay and tuberculin skin test was 6·1 (95% CI 2·3-11·5). Pooled RR for rates of disease progression in individuals who were positive by IFN-γ release assay and tuberculin skin test who were untreated versus those who were treated was 7·84 (95% CI 4·44-13·83). INTERPRETATION: IFN-γ release assays have a better predictive ability than tuberculin skin tests. Individuals who are positive by IFN-γ release assay might benefit from preventive treatment, but those who are positive by tuberculin skin test probably will not. Dual testing might improve detection, but further confirmation is needed. FUNDING: National Natural Science Foundation of China and Natural Foundation of Yunnan Province.
Sujet(s)
Interféron gamma/métabolisme , Tuberculose latente/diagnostic , Test tuberculinique , Antituberculeux/usage thérapeutique , Humains , Tuberculose latente/traitement médicamenteuxRÉSUMÉ
Nine new and nineteen known compounds were isolated and identified from Rosmarinus officinalis under the guidance of bioassay and LCMS. They all belonged to abietane diterpenoids which enriched the types of compounds in R. officinalis, especially the discovery of a series of 20-norabietane diterpenoids (4, 6-9, and 26-27). The antioxidative damage activity of the compounds was tested on H2O2 damaged SH-SY5Y cells. Compounds 5, 6, and 7 presented moderate ability for promoting the growth of damaged cells. Compounds 10, 11, 13-20, 27, and 28 displayed a high antioxidative damage effect whose cell viability rates were more than 80%. The antioxidative damage effect of 11, 16, 18, and 20 were higher than that of EGCG (positive control) in which 11, 18, and 20 were the acetylated derivatives of carnosic acid (10), 7α-methoxy-isocarnosol (16), and carnosol (19), respectively. It suggested that 10-carboxyl/formyl of abietane diterpenoids was essential for maintaining the antioxidative damage activity and the adjacent hydroxyl groups on the benzene ring was less important for holding the bioactivity. These acetylated derivatives with high bioactivity and stability could be regarded as new sources of antioxidants or antioxidative damage agents being used in the food and medical industry.
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Abiétanes/composition chimique , Antioxydants/composition chimique , Extraits de plantes/composition chimique , Rosmarinus/composition chimique , Abiétanes/pharmacologie , Antioxydants/pharmacologie , Lignée cellulaire , Survie cellulaire/effets des médicaments et des substances chimiques , Humains , Peroxyde d'hydrogène/toxicité , Extraits de plantes/pharmacologieRÉSUMÉ
OBJECTIVE: Right aortic arch (RAA) can be associated with chromosomal anomalies. However, the incidence of chromosomal anomalies when RAA is isolated (iRAA), ie, not associated with intracardiac anomalies, varies between different studies (0%-28.5%). We have performed a meta-analysis to allow a more accurate prenatal counselling. METHODS: We searched PubMed, Embase, and Web of Science for articles related to chromosomal anomalies among iRAA fetuses until April 2019. A total of 22 relevant studies, including 670 fetuses, were selected in the final meta-analysis. RESULTS: The results revealed that the overall rates of chromosomal anomalies and 22q11.2 deletion in iRAA fetuses were 7.5% (95% confidence interval [CI], 4.7%-10.8%) and 4.3% (95% CI, 2.6%-6.4%), respectively, while the rates were lower in iRAA without extracardiac anomalies, 4.7% (95% CI, 1.1%-10.8%) and 2.4% (95% CI, 0.5%-5.7%). The rate of chromosomal or copy number variants including 22q11.2 deletion identified by chromosomal microarray analysis (CMA) in iRAA fetuses was 8.2% (95% CI, 5.0%-12.1%) and 3.7% (95% CI, 1.7%-6.6%), respectively, compared with 5.1% (95% CI, 2.5%-8.4%) and 2.4% (95% CI, 0.7%-5.1%) identified by traditional karyotyping. CONCLUSIONS: A considerable proportion of iRAA cases have associated chromosomal anomalies and prevalence of associated 22q11.2 deletion, and CMA is recommended if invasive prenatal testing is performed.
Sujet(s)
Aberrations des chromosomes/statistiques et données numériques , Anneau vasculaire/génétique , Délétion de segment de chromosome , Chromosomes humains de la paire 22/génétique , Femelle , Humains , Caryotypage , Analyse sur microréseau , Grossesse , Diagnostic prénatal/méthodes , Anneau vasculaire/diagnosticRÉSUMÉ
BACKGROUND: Bystander CPR (B-CPR) is crucial to increase survival of out-of-hospital cardiac arrest (OHCA), and this study is performed to assess the willingness and obstacles of Chinese healthcare professionals (HCPs) to perform B-CPR on strangers, as well as the factors associated with the willingness. METHODS: An internet-based questionnaire surveying demographic information, CPR training, CPR knowledge, willingness, and obstacles to perform B-CPR among 10,393 HCPs. A multivariate logistic regression analysis was used to evaluate the factors associated with the willingness. RESULTS: Here, 73.9% of HCPs were willing to perform B-CPR on strangers in China. The factors associated with the willingness were as follows: female, senior, working in Third-class hospitals, working in Pre-hospital emergency and Cardiology or Cardiac surgery, receiving current training, having adequate CPR knowledge. The main obstacles were fear of infection via mouth-to-mouth ventilations (MMV), fear of being blackmailed and fear of legal liability. CONCLUSION: About three quarters of HCPs are willing to perform B-CPR. Female HCPs, those who have more CPR experience, adequate knowledge, and recent training are more likely to perform B-CPR. Reform of the legal and credit system are needed, and recommendation of hands-only CPR is a possibility to encourage HCPs to perform B-CPR on strangers.