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1.
Cell ; 184(3): 723-740.e21, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33508230

RESUMO

Elucidating the regulatory mechanisms of human brain evolution is essential to understanding human cognition and mental disorders. We generated multi-omics profiles and constructed a high-resolution map of 3D genome architecture of rhesus macaque during corticogenesis. By comparing the 3D genomes of human, macaque, and mouse brains, we identified many human-specific chromatin structure changes, including 499 topologically associating domains (TADs) and 1,266 chromatin loops. The human-specific loops are significantly enriched in enhancer-enhancer interactions, and the regulated genes show human-specific expression changes in the subplate, a transient zone of the developing brain critical for neural circuit formation and plasticity. Notably, many human-specific sequence changes are located in the human-specific TAD boundaries and loop anchors, which may generate new transcription factor binding sites and chromatin structures in human. Collectively, the presented data highlight the value of comparative 3D genome analyses in dissecting the regulatory mechanisms of brain development and evolution.


Assuntos
Encéfalo/embriologia , Evolução Molecular , Feto/embriologia , Genoma , Organogênese/genética , Animais , Sequência de Bases , Cromatina/metabolismo , Elementos de DNA Transponíveis/genética , Elementos Facilitadores Genéticos/genética , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Macaca mulatta , Camundongos , Especificidade da Espécie , Sintenia/genética , Fatores de Transcrição/metabolismo
2.
Proc Natl Acad Sci U S A ; 121(4): e2312556121, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38227655

RESUMO

Hemorrhagic fever with renal syndrome (HFRS) is a zoonotic disease caused by the rodent-transmitted orthohantaviruses (HVs), with China possessing the most cases globally. The virus hosts in China are Apodemus agrarius and Rattus norvegicus, and the disease spread is strongly influenced by global climate dynamics. To assess and predict the spatiotemporal trends of HFRS from 2005 to 2098, we collected historical HFRS data in mainland China (2005-2020), historical and projected climate and population data (2005-2098), and spatial variables including biotic, environmental, topographical, and socioeconomic. Spatiotemporal predictions and mapping were conducted under 27 scenarios incorporating multiple integrated representative concentration pathway models and population scenarios. We identify the type of magistral HVs host species as the best spatial division, including four region categories. Seven extreme climate indices associated with temperature and precipitation have been pinpointed as key factors affecting the trends of HFRS. Our predictions indicate that annual HFRS cases will increase significantly in 62 of 356 cities in mainland China. Rattus regions are predicted to be the most active, surpassing Apodemus and Mixed regions. Eighty cities are identified as at severe risk level for HFRS, each with over 50 reported cases annually, including 22 new cities primarily located in East China and Rattus regions after 2020, while 6 others develop new risk. Our results suggest that the risk of HFRS will remain high through the end of this century, with Rattus norvegicus being the most active host, and that extreme climate indices are significant risk factors. Our findings can inform evidence-based policymaking regarding future risk of HFRS.


Assuntos
Febre Hemorrágica com Síndrome Renal , Ratos , Animais , Febre Hemorrágica com Síndrome Renal/epidemiologia , Febre Hemorrágica com Síndrome Renal/etiologia , Clima , Zoonoses , China/epidemiologia , Murinae , Incidência
3.
Proc Natl Acad Sci U S A ; 120(33): e2304750120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549267

RESUMO

There has long been controversy over the potential for asymptomatic cases of the influenza virus to have the capacity for onward transmission, but recognition of asymptomatic transmission of COVID-19 stimulates further research into this topic. Here, we develop a Bayesian methodology to analyze detailed data from a large cohort of 727 households and 2515 individuals in the 2009 pandemic influenza A(H1N1) outbreak in Hong Kong to characterize household transmission dynamics and to estimate the relative infectiousness of asymptomatic versus symptomatic influenza cases. The posterior probability that asymptomatic cases [36% of cases; 95% credible interval (CrI): 32%, 40%] are less infectious than symptomatic cases is 0.82, with estimated relative infectiousness 0.57 (95% CrI: 0.11, 1.54). More data are required to strengthen our understanding of the contribution of asymptomatic cases to the spread of influenza.


Assuntos
COVID-19 , Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Humanos , Teorema de Bayes , COVID-19/epidemiologia , Surtos de Doenças
4.
Cell Mol Life Sci ; 81(1): 128, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472451

RESUMO

Epigenetic dysregulation that leads to alterations in gene expression and is suggested to be one of the key pathophysiological factors of Parkinson's disease (PD). Here, we found that α-synuclein preformed fibrils (PFFs) induced histone H3 dimethylation at lysine 9 (H3K9me2) and increased the euchromatic histone methyltransferases EHMT1 and EHMT2, which were accompanied by neuronal synaptic damage, including loss of synapses and diminished expression levels of synaptic-related proteins. Furthermore, the levels of H3K9me2 at promoters in genes that encode the synaptic-related proteins SNAP25, PSD95, Synapsin 1 and vGLUT1 were increased in primary neurons after PFF treatment, which suggests a linkage between H3K9 dimethylation and synaptic dysfunction. Inhibition of EHMT1/2 with the specific inhibitor A-366 or shRNA suppressed histone methylation and alleviated synaptic damage in primary neurons that were treated with PFFs. In addition, the synaptic damage and motor impairment in mice that were injected with PFFs were repressed by treatment with the EHMT1/2 inhibitor A-366. Thus, our findings reveal the role of histone H3 modification by EHMT1/2 in synaptic damage and motor impairment in a PFF animal model, suggesting the involvement of epigenetic dysregulation in PD pathogenesis.


Assuntos
Transtornos Motores , Doença de Parkinson , Animais , Camundongos , Histonas/metabolismo , Metilação , Neurônios/metabolismo , alfa-Sinucleína/metabolismo
5.
Nucleic Acids Res ; 51(14): 7496-7519, 2023 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-37283053

RESUMO

Modified nucleotides in non-coding RNAs, such as tRNAs and snRNAs, represent an important layer of gene expression regulation through their ability to fine-tune mRNA maturation and translation. Dysregulation of such modifications and the enzymes installing them have been linked to various human pathologies including neurodevelopmental disorders and cancers. Several methyltransferases (MTases) are regulated allosterically by human TRMT112 (Trm112 in Saccharomyces cerevisiae), but the interactome of this regulator and targets of its interacting MTases remain incompletely characterized. Here, we have investigated the interaction network of human TRMT112 in intact cells and identify three poorly characterized putative MTases (TRMT11, THUMPD3 and THUMPD2) as direct partners. We demonstrate that these three proteins are active N2-methylguanosine (m2G) MTases and that TRMT11 and THUMPD3 methylate positions 10 and 6 of tRNAs, respectively. For THUMPD2, we discovered that it directly associates with the U6 snRNA, a core component of the catalytic spliceosome, and is required for the formation of m2G, the last 'orphan' modification in U6 snRNA. Furthermore, our data reveal the combined importance of TRMT11 and THUMPD3 for optimal protein synthesis and cell proliferation as well as a role for THUMPD2 in fine-tuning pre-mRNA splicing.


Assuntos
Precursores de RNA , Proteínas de Saccharomyces cerevisiae , Humanos , Precursores de RNA/genética , Precursores de RNA/metabolismo , Splicing de RNA , Spliceossomos/metabolismo , RNA Nuclear Pequeno/genética , RNA Nuclear Pequeno/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proliferação de Células/genética , Biossíntese de Proteínas , Metiltransferases/genética , tRNA Metiltransferases/genética , Proteínas de Saccharomyces cerevisiae/genética
6.
Proc Natl Acad Sci U S A ; 119(18): e2105006119, 2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35467985

RESUMO

The world has committed trillions in fiscal expenditures to reboot the economy in the post­COVID-19 era. However, the effectiveness and the equity impacts of current fiscal stimuli are not fully understood. Using an extended adaptive regional input­output model, we assess the short-term impacts (2020 through 2022) of feasible stimuli on the global economy and the labor market. Our findings show that the stimuli pledged by 26 countries, i.e., 2.4 trillion euros in total, are effective in keeping the recession short and shallow by saving 53 million to 57 million jobs (compared to the no-stimulus scenario). However, the stimuli exacerbate income inequity at the global scale if we define "equity" as those who suffer more from the pandemic should receive more assistance. Low-skilled workers in these countries, who suffer more from the pandemic than high-skilled workers, benefit 38 to 41% less from the job-creation effects of the current fiscal stimuli. As an alternative, low-carbon stimuli can achieve a balance between effectiveness and equity at the global level. Low-carbon stimuli save 55 million to 58 million jobs and decrease income inequality by 2 to 3% globally compared to the currently pledged stimuli. Country-level situations are more complicated, as modifying the current stimuli to achieve more "greenness" brings win­win in effectiveness and equity in some countries, while in the others, more greenness and equity are at the expense of less job savings. Our findings underscore the need to consider the overlooked trade-offs between effectiveness, equity, and greenness, both globally and nationally, when designing further postpandemic fiscal stimuli.


Assuntos
Emprego , Renda , Mudança Climática , Humanos
7.
Nano Lett ; 24(28): 8567-8574, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38959438

RESUMO

Phagocytosis is an essential mechanism of the human immune system where pathogens are eliminated by immune cells. The CCN1 protein plays an important role in the phagocytosis of Staphylococcus aureus by favoring the bridging of the αVß3 integrin to the bacterial peptidoglycan (PG), through mechanical forces that remain unknown. Here, we employ single-molecule experiments to unravel the nanomechanics of the PG-CCN1-αVß3 ternary complex. While CCN1 binds αVß3 integrins with moderate force (∼60 pN), much higher binding strengths (up to ∼800 pN) are observed between CCN1 and PG. Notably, the strength of both CCN1-αVß3 and CCN1-PG bonds is dramatically enhanced by tensile loading, favoring a model in which mechanical stress induces the exposure of cryptic integrin binding sites in CCN1 and multivalent binding between CCN1 lectin sites and monosaccharides along the PG glycan chains.


Assuntos
Proteína Rica em Cisteína 61 , Integrina alfaVbeta3 , Fagocitose , Staphylococcus aureus , Staphylococcus aureus/metabolismo , Staphylococcus aureus/fisiologia , Humanos , Proteína Rica em Cisteína 61/metabolismo , Proteína Rica em Cisteína 61/química , Integrina alfaVbeta3/metabolismo , Peptidoglicano/metabolismo , Peptidoglicano/química , Ligação Proteica , Sítios de Ligação
8.
Am J Epidemiol ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38904437

RESUMO

Prior infection with SARS-CoV-2 can provide protection against infection and severe COVID-19. We aimed to determine the impact of pre-existing immunity on the vaccine effectiveness (VE) estimates. We systematically reviewed and meta-analysed 66 test-negative design (TND) studies that examined VE against infection or severe disease (hospitalization, ICU admission, or death) for primary vaccination series. Pooled VE among studies that included people with prior COVID-19 infection was lower against infection (pooled VE: 77%; 95% confidence interval (CI): 72%, 81%) and severe disease (pooled VE: 86%; 95% CI: 83%, 89%), compared with studies that excluded people with prior COVID-19 infection (pooled VE against infection: 87%; 95% CI: 85%, 89%; pooled VE against severe disease: 93%; 95% CI: 91%, 95%). There was a negative correlation between VE estimates against infection and severe disease, and the cumulative incidence of cases before the start of the study or incidence rates during the study period. We found clear empirical evidence that higher levels of pre-existing immunity were associated with lower VE estimates. Prior infections should be treated as both a confounder and effect modificatory when the policies target the whole population or stratified by infection history, respectively.

9.
Small ; 20(9): e2305951, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37817356

RESUMO

Conductive microfibers play a significant role in the flexibility, stretchability, and conductivity of electronic skin (e-skin). Currently, the fabrication of conductive microfibers suffers from either time-consuming and complex operations or is limited in complex fabrication environments. Thus, it presents a one-step method to prepare conductive hydrogel microfibers based on microfluidics for the construction of ultrastretchable e-skin. The microfibers are achieved with conductive MXene cores and hydrogel shells, which are solidified with the covalent cross-linking between sodium alginate and calcium chloride, and mechanically enhanced by the complexation reaction of poly(vinyl alcohol) and sodium hydroxide. The microfiber conductivities are tailorable by adjusting the flow rate and concentration of core and shell fluids, which is essential to more practical applications in complex scenarios. More importantly, patterned e-skin based on conductive hydrogel microfibers can be constructed by combining microfluidics with 3D printing technology. Because of the great advantages in mechanical and electrical performance of the microfibers, the achieved e-skin shows impressive stretching and sensitivity, which also demonstrate attractive application values in motion monitoring and gesture recognition. These characteristics indicate that the ultrastretchable e-skin based on conductive hydrogel microfibers has great potential for applications in health monitoring, wearable devices, and smart medicine.


Assuntos
Hidrogéis , Pele , Condutividade Elétrica , Eletricidade , Alginatos
10.
Small ; : e2402531, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727180

RESUMO

The efficacy of electron transport layers (ETLs) is pivotal for optimizing the device performance of perovskite photovoltaic applications. However, colloidal dispersions of SnO2 are prone to aggregation and possess structural defects, such as terminal-hydroxyls (OHT) and oxygen vacancies (VOs), which can degrade the quality of ETLs, impede charge extraction and transport, and affect the nucleation and growth processes of the perovskite layer. In this study, the Sb(OH)4 - ions hydrolyzed from SbCl3 in colloidal dispersion can bind to defect sites and effectively stabilize the SnO2 nanocrystals are demonstrated. Upon oxidative annealing, a Sb2O5@SnO2 composite film is formed, in which the Sb2O5 not only mitigates the aforementioned defects but also broadens the energy range of unoccupied states through its dispersed conduction band. The increased electron affinity (EA) facilitates more efficient capture of photoexcited electrons from the perovskite layer, thus augmenting electron extraction and minimizing electron-hole recombination. As a result, a significant improvement in power conversion efficiency (PCE) from 22.60% to 24.54% is achieved, with an open circuit voltage (VOC) of up to 1.195 V, along with excellent stability of unsealed devices under various conditions. This study provides valuable insights for the understanding and design of ETLs in perovskite photovoltaic applications.

11.
Small ; : e2401834, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623962

RESUMO

Different facets in perovskite crystals exhibit distinct atomic arrangements, influencing their electronic, physical, and chemical properties. Perovskite films incorporating tin oxide (SnO2) as the electron transport layer face challenges in facet regulation. This study reveals that tea saponin (TS), a natural compound serves as a SnO2 modifier, facilitates optimal growth of perovskite crystals on the (111) facet. The modification promotes preferential crystal orientation through hydrogen bond and Lewis coordination. TS forms a chelate with SnO2, resulting in a smoother film and n-type doping, leading to improved carrier extraction and reduced defects. The TS-modified perovskite solar cells achieve a champion efficiency of 24.2%, leveraging from an obvious enhancement of open-circuit voltage (Voc) of 1.18 V and fill factor (FF) of 82.8%. The devices also demonstrate enhanced humidity tolerance and storage stability, ensuring improved stability without encapsulation.

12.
Appl Environ Microbiol ; : e0056924, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916292

RESUMO

Microbial community adaptability to pH stress plays a crucial role in biofilm formation. This study aims to investigate the regulatory mechanisms of exogenous putrescine on pH stress, as well as enhance understanding and application for the technical measures and molecular mechanisms of biofilm regulation. Findings demonstrated that exogenous putrescine acted as a switch-like distributor affecting microorganism pH stress, thus promoting biofilm formation under acid conditions while inhibiting it under alkaline conditions. As pH decreases, the protonation degree of putrescine increases, making putrescine more readily adsorbed. Protonated exogenous putrescine could increase cell membrane permeability, facilitating its entry into the cell. Subsequently, putrescine consumed intracellular H+ by enhancing the glutamate-based acid resistance strategy and the γ-aminobutyric acid metabolic pathway to reduce acid stress on cells. Furthermore, putrescine stimulated ATPase expression, allowing for better utilization of energy in H+ transmembrane transport and enhancing oxidative phosphorylation activity. However, putrescine protonation was limited under alkaline conditions, and the intracellular H+ consumption further exacerbated alkali stress and inhibits cellular metabolic activity. Exogenous putrescine promoted the proportion of fungi and acidophilic bacteria under acidic stress and alkaliphilic bacteria under alkali stress while having a limited impact on fungi in alkaline biofilms. Increasing Bdellovibrio under alkali conditions with putrescine further aggravated the biofilm decomposition. This research shed light on the unclear relationship between exogenous putrescine, environmental pH, and pH stress adaptability of biofilm. By judiciously employing putrescine, biofilm formation could be controlled to meet the needs of engineering applications with different characteristics.IMPORTANCEThe objective of this study is to unravel the regulatory mechanism by which exogenous putrescine influences biofilm pH stress adaptability and understand the role of environmental pH in this intricate process. Our findings revealed that exogenous putrescine functioned as a switch-like distributor affecting the pH stress adaptability of biofilm-based activated sludge, which promoted energy utilization for growth and reproduction processes under acidic conditions while limiting biofilm development to conserve energy under alkaline conditions. This study not only clarified the previously ambiguous relationship between exogenous putrescine, environmental pH, and biofilm pH stress adaptability but also offered fresh insights into enhancing biofilm stability within extreme environments. Through the modulation of energy utilization, exerting control over biofilm growth and achieving more effective engineering goals could be possible.

13.
Cardiovasc Diabetol ; 23(1): 73, 2024 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-38365751

RESUMO

BACKGROUND: Stress hyperglycemia ratio (SHR) has recently been recognized as a novel biomarker that accurately reflects acute hyperglycemia status and is associated with poor prognosis of heart failure. We evaluated the relationship between SHR and clinical outcomes in patients with severe aortic stenosis receiving transcatheter aortic valve replacement (TAVR). METHODS: There were 582 patients with severe native aortic stenosis who underwent TAVR consecutively enrolled in the study. The formula used to determine SHR was as follows: admission blood glucose (mmol/L)/(1.59×HbA1c[%]-2.59). The primary endpoint was defined as all-cause mortality, while secondary endpoints included a composite of cardiovascular mortality or readmission for heart failure, and major adverse cardiovascular events (MACE) including cardiovascular mortality, non-fatal myocardial infarction, and non-fatal stroke. Multivariable Cox regression and restricted cubic spline analysis were employed to assess the relationship between SHR and endpoints, with hazard ratios (HRs) and 95% confidence intervals (CIs). RESULTS: During a median follow-up of 3.9 years, a total of 130 cases (22.3%) of all-cause mortality were recorded. Results from the restricted cubic spline analysis indicated a linear association between SHR and all endpoints (p for non-linearity > 0.05), even after adjustment for other confounding factors. Per 0.1 unit increase in SHR was associated with a 12% (adjusted HR: 1.12, 95% CI: 1.04-1.21) higher incidence of the primary endpoint, a 12% (adjusted HR: 1.12, 95% CI: 1.02-1.22) higher incidence of cardiovascular mortality or readmission for heart failure, and a 12% (adjusted HR: 1.12, 95% CI: 1.01-1.23) higher incidence of MACE. Subgroup analysis revealed that SHR had a significant interaction with diabetes mellitus with regard to the risk of all-cause mortality (p for interaction: 0.042). Kaplan-Meier survival analysis showed that there were significant differences in the incidence of all endpoints between the two groups with 0.944 as the optimal binary cutoff point of SHR (all log-rank test: p < 0.05). CONCLUSIONS: Our study indicates linear relationships of SHR with the risk of all-cause mortality, cardiovascular mortality or readmission for heart failure, and MACE in patients with severe aortic stenosis receiving TAVR after a median follow-up of 3.9 years. Patients with an SHR exceeding 0.944 had a poorer prognosis compared to those with lower SHR values.


Assuntos
Estenose da Valva Aórtica , Insuficiência Cardíaca , Hiperglicemia , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/efeitos adversos , Prognóstico , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico por imagem , Estenose da Valva Aórtica/cirurgia , Estudos Prospectivos , Resultado do Tratamento , Hiperglicemia/diagnóstico , Fatores de Risco
14.
Microb Pathog ; 188: 106570, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38341108

RESUMO

High-concentrate diet induce subacute ruminal acidosis (SARA) and cause liver damage in ruminants. It has been reported that forkhead box protein A2 (FOXA2) can enhance mitochondrial membrane potential but its function in mitochondrial dysfunction induced by high concentrate diets is still unknown. Therefore, the aim of this study was to elucidate the effect of high-concentrate (HC) diet on hepatic FOXA2 expression, mitochondrial unfolded protein response (UPRmt), mitochondrial dysfunction and oxidative stress. A total of 12 healthy mid-lactation Holstein cows were selected and randomized into 2 groups: the low concentrate (LC) diet group (concentrate:forage = 4:6) and HC diet group (concentrate:forage = 6:4). The trial lasted 21 d. The rumen fluid, blood and liver tissue were collected at the end of the experiment. The results showed that the rumen fluid pH level was reduced in the HC group and the pH was lower than 5.6 for more than 4 h/d, indicating that feeding HC diets successfully induced SARA in dairy cows. Both FOXA2 mRNA and protein abundance were significantly reduced in the liver of the HC group compared with the LC group. The activity of antioxidant enzymes (CAT, G6PDH, T-SOD, Cu/Zn SOD, Mn SOD) and mtDNA copy number in the liver tissue of the HC group decreased, while the level of H2O2 significantly increased, this increase was accompanied by a decrease in oxidative phosphorylation (OXPHOS). The balance of mitochondrial division and fusion was disrupted in the HC group, as evidenced by the decreased mRNA level of OPA1, MFN1, and MFN2 and increased mRNA level of Drp1, Fis1, and MFF. At the same time, HC diet downregulated the expression level of SIRT1, SIRT3, PGC-1α, TFAM, and Nrf 1 to inhibit mitochondrial biogenesis. The HC group induced UPRmt in liver tissue by upregulating the mRNA and protein levels of CLPP, LONP1, CHOP, Hsp10, and Hsp60. In addition, HC diet could increase the protein abundance of Bax, CytoC, Caspase 3 and Cleaved-Caspase 3, while decrease the protein abundance of Bcl-2 and the Bcl-2/Bax ratio. Overall, our study suggests that the decreased expression of FOXA2 may be related to UPRmt, mitochondrial dysfunction, oxidative stress, and apoptosis in the liver of dairy cows fed a high concentrate diet.


Assuntos
Peróxido de Hidrogênio , Doenças Mitocondriais , Animais , Feminino , Bovinos , Caspase 3/metabolismo , Peróxido de Hidrogênio/metabolismo , Proteína X Associada a bcl-2/metabolismo , Dieta/veterinária , Fígado/metabolismo , Lactação , Estresse Oxidativo , Superóxido Dismutase/metabolismo , RNA Mensageiro/metabolismo , Resposta a Proteínas não Dobradas , Doenças Mitocondriais/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Leite/metabolismo , Concentração de Íons de Hidrogênio , Ração Animal
15.
Chem Res Toxicol ; 37(6): 944-956, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38771988

RESUMO

Celastrol (Cel), extracted from Tripterygium wilfordii Hook, is a potential antiobesity drug, except for its adverse reactions in clinic. In the present study, we synthesized a promising celastrol-chitosan conjugate (Cel-CS1K) and evaluated its antiobesity effect and biological safety in diet-induced obese mice. Cel-CS1K showed higher drug loading (over 10 wt %), good solubility (18-19 mg/mL) in water, slower peak time (Tmax = 4 h), and clearance (T1/2 = 8.97 h) in rats. Cel-CS1K effectively attenuated the cytotoxicity, celastrol-induced apoptosis, and fat accumulation of hepatocytes. Cel-CS1K reduced body weight and dietary amount same as the free Cel but with lower toxicity in blood, liver, and testis. Cel-CS1K improved the glucose homeostasis, HDL-C level, insulin sensitivity, and leptin sensitivity, while it significantly reduced the gene expression levels of LDL-C, TG, and TC in obese mice. Furthermore, the adipose-related gene expression levels provided evidence in support of a role for Cel-CS1K in losing weight by the multimode regulation. Overall, Cel-CS1K provides a translatable therapeutic strategy for the treatment of diet-induced obese humans.


Assuntos
Fármacos Antiobesidade , Quitosana , Obesidade , Triterpenos Pentacíclicos , Triterpenos , Animais , Triterpenos Pentacíclicos/farmacologia , Triterpenos Pentacíclicos/química , Obesidade/tratamento farmacológico , Masculino , Triterpenos/química , Triterpenos/farmacologia , Camundongos , Quitosana/química , Quitosana/farmacologia , Fármacos Antiobesidade/farmacologia , Fármacos Antiobesidade/química , Ratos , Dieta Hiperlipídica/efeitos adversos , Humanos , Ratos Sprague-Dawley , Camundongos Endogâmicos C57BL , Apoptose/efeitos dos fármacos , Tripterygium/química
16.
PLoS Biol ; 19(2): e3001090, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33591965

RESUMO

Sweating is a basic skin function in body temperature control. In sweat glands, salt excretion and reabsorption are regulated to avoid electrolyte imbalance. To date, the mechanism underlying such regulation is not fully understood. Corin is a transmembrane protease that activates atrial natriuretic peptide (ANP), a cardiac hormone essential for normal blood volume and pressure. Here, we report an unexpected role of corin in sweat glands to promote sweat and salt excretion in regulating electrolyte homeostasis. In human and mouse eccrine sweat glands, corin and ANP are expressed in the luminal epithelial cells. In corin-deficient mice on normal- and high-salt diets, sweat and salt excretion is reduced. This phenotype is associated with enhanced epithelial sodium channel (ENaC) activity that mediates Na+ and water reabsorption. Treatment of amiloride, an ENaC inhibitor, normalizes sweat and salt excretion in corin-deficient mice. Moreover, treatment of aldosterone decreases sweat and salt excretion in wild-type (WT), but not corin-deficient, mice. These results reveal an important regulatory function of corin in eccrine sweat glands to promote sweat and salt excretion.


Assuntos
Glândulas Écrinas/fisiologia , Serina Endopeptidases/metabolismo , Cloreto de Sódio/metabolismo , Animais , Fator Natriurético Atrial/metabolismo , Glândulas Écrinas/metabolismo , Eletrólitos/metabolismo , Folículo Piloso/metabolismo , Homeostase/fisiologia , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Serina Endopeptidases/genética , Suor/química , Água/metabolismo
17.
J Org Chem ; 89(4): 2505-2515, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38315825

RESUMO

A novel iodine-promoted difunctionalization of α-C sites in enaminones was demonstrated as a means of synthesizing a variety of fully substituted thiazoles by constructing C-C(CO), C-S, and C-N bonds. This transformation allows the realization of enaminones as unusual aryl C2 synthons and simultaneously allows the thioylation and dicarbonylation of α-C sites. A preliminary mechanistic study was performed and indicated that the cleavage of C═C bonds in enaminones involves a bicyclization/ring-opening and oxidative coupling sequence.

18.
Org Biomol Chem ; 22(19): 3866-3870, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38646715

RESUMO

An FeCl3-catalyzed oxidative condensation of NH-1,2,3-triazoles, aryl methyl ketones (or acetophenones) and DMF (N,N-dimethylformamide) for the synthesis of ß-(1,2,3-triazolyl)-ketones was developed. DMF serves as a one-carbon source, and the resulting products display diverse reaction selectivity, highlighting the existence of distinct approaches.

19.
Epidemiol Infect ; 152: e43, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38500342

RESUMO

From 2020 to December 2022, China implemented strict measures to contain the spread of severe acute respiratory syndrome coronavirus 2. However, despite these efforts, sustained outbreaks of the Omicron variants occurred in 2022. We extracted COVID-19 case numbers from May 2021 to October 2022 to identify outbreaks of the Delta and Omicron variants in all provinces of mainland China. We found that omicron outbreaks were more frequent (4.3 vs. 1.6 outbreaks per month) and longer-lasting (mean duration: 13 vs. 4 weeks per outbreak) than Delta outbreaks, resulting in a total of 865,100 cases, of which 85% were asymptomatic. Despite the average Government Response Index being 12% higher (95% confidence interval (CI): 9%, 15%) in Omicron outbreaks, the average daily effective reproduction number (Rt) was 0.45 higher (95% CI: 0.38, 0.52, p < 0.001) than in Delta outbreaks. Omicron outbreaks were suppressed in 32 days on average (95% CI: 26, 39), which was substantially longer than Delta outbreaks (14 days; 95% CI: 11, 19; p = 0.004). We concluded that control measures effective against Delta could not contain Omicron outbreaks in China. This highlights the need for continuous evaluation of new variants' epidemiology to inform COVID-19 response decisions.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Surtos de Doenças , China/epidemiologia
20.
Environ Sci Technol ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38319870

RESUMO

As an emerging type of pollutant, microplastics have become a global environmental problem. Approximately, a fifth of the global burden of type 2 diabetes can be attributed to air particulate pollution. However, scientific knowledge remains limited about the effects of airborne nanoplastics (NPs) exposure on metabolic diseases. In this experiment, a whole-body exposure system was used to simulate the real atmospheric environment, and three exposure concentrations combined with the actual environmental concentration were selected to explore the effects of airborne NPs on metabolic diseases. Based on histological analyses, metabolic studies, gene expression, metabolites, and molecular signaling analyses, mice exposed to airborne NPs were observed to show a phenotype of systemic inflammation and complete insulin resistance featuring excessive drinking and eating, weight loss, elevated blood glucose, and decreased triglyceride levels. After airborne NPs exposure, mice were intolerant to glucose and tolerant to insulin. In addition, airborne NPs exposure could result in long-term irreversible hyperglycemia. Together, the research findings provide a strong basis for understanding the hazards of airborne nanopollution on metabolic disorders.

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