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1.
Proc Natl Acad Sci U S A ; 121(11): e2312136121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38446848

RESUMO

Anxiety is a remarkably common condition among patients with pharyngitis, but the relationship between these disorders has received little research attention, and the underlying neural mechanisms remain unknown. Here, we show that the densely innervated pharynx transmits signals induced by pharyngeal inflammation to glossopharyngeal and vagal sensory neurons of the nodose/jugular/petrosal (NJP) superganglia in mice. Specifically, the NJP superganglia project to norepinephrinergic neurons in the nucleus of the solitary tract (NTSNE). These NTSNE neurons project to the ventral bed nucleus of the stria terminalis (vBNST) that induces anxiety-like behaviors in a murine model of pharyngeal inflammation. Inhibiting this pharynx→NJP→NTSNE→vBNST circuit can alleviate anxiety-like behaviors associated with pharyngeal inflammation. This study thus defines a pharynx-to-brain axis that mechanistically links pharyngeal inflammation and emotional response.


Assuntos
Faringite , Faringe , Humanos , Animais , Camundongos , Ansiedade , Encéfalo , Células Receptoras Sensoriais , Inflamação
2.
Proc Natl Acad Sci U S A ; 120(24): e2302854120, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37276396

RESUMO

Stomata are pores found in the epidermis of stems or leaves that modulate both plant gas exchange and water/nutrient uptake. The development and function of plant stomata are regulated by a diverse range of environmental cues. However, how carbohydrate status in preexisting leaves might determine systemic stomatal formation within newly developing leaves has remained obscure. The glucose (Glc) sensor HEXOKINASE1 (HXK1) has been reported to decrease the stability of an ethylene/Glc signaling transcriptional regulator, EIN3 (ETHYLENE INSENSITIVE3). EIN3 in turn directly represses the expression of SUC2 (sucrose transporter 2), encoding a master transporter of sucrose (Suc). Further, KIN10, a nuclear regulator involved in energy homeostasis, has been reported to repress the transcription factor SPCH (SPEECHLESS), a master regulator of stomatal development. Here, we demonstrate that the Glc status of preexisting leaves determines systemic stomatal development within newly developing leaves by the HXK1-¦EIN3-¦SUC2 module. Further, increasing Glc levels in preexisting leaves results in a HXK1-dependent decrease of EIN3 and increase of SUC2, triggering the perception, amplification and relay of HXK1-dependent Glc signaling and thereby triggering Suc transport from mature to newly developing leaves. The HXK1-¦EIN3-¦SUC2 molecular module thereby drives systemic Suc transport from preexisting leaves to newly developing leaves. Subsequently, increasing Suc levels within newly developing leaves promotes stomatal formation through the established KIN10⟶ SPCH module. Our findings thus show how a carbohydrate signal in preexisting leaves is sensed, amplified and relayed to determine the extent of systemic stomatal development within newly developing leaves.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Açúcares/metabolismo , Folhas de Planta/metabolismo , Etilenos/metabolismo , Sacarose/metabolismo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo
3.
Nano Lett ; 24(10): 3204-3212, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38416569

RESUMO

The flicker frequency of incident light constitutes a critical determinant in biology. Nevertheless, the exploration of methods to simulate external light stimuli with varying frequencies and develop artificial retinal neurons capable of responsive behavior remains an open question. This study presents an artificial neuron comprising organic phototransistors. The triggering properties of neurons are modulated by optical input, enabling them to execute rudimentary synaptic functions, emulating the biological characteristics of retinal neurons. The artificial retinal neuron exhibits varying responses to incoming light frequencies, allowing it to replicate the persistent visual behavior of the human eye and facilitating image discrimination. Additionally, through seamless integration with circuitry, it can execute motion recognition on a machine cart, preventing collisions with high-speed obstacles. The artificial retinal neuron offers a cost-effective and energy-efficient route for future mobile robot processors.


Assuntos
Retina , Visão Ocular , Humanos , Neurônios/fisiologia
4.
Nano Lett ; 24(7): 2345-2351, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38334460

RESUMO

Nonvolatile multistate manipulation of two-dimensional (2D) magnetic materials holds promise for low dissipation, highly integrated, and versatile spintronic devices. Here, utilizing density functional theory calculations and Monte Carlo simulations, we report the realization of nonvolatile and multistate control of topological magnetism in monolayer CrI3 by constructing multiferroic heterojunctions with quadruple-well ferroelectric (FE) materials. The Pt2Sn2Te6/CrI3 heterojunction exhibits multiple magnetic phases upon modulating FE polarization states of FE layers and interlayer sliding. These magnetic phases include Bloch-type skyrmions and ferromagnetism, as well as a newly discovered topological magnetic structure. We reveal that the Dzyaloshinskii-Moriya interaction (DMI) induced by interfacial coupling plays a crucial role in magnetic skyrmion manipulation, which aligns with the Fert-Levy mechanism. Moreover, a regular magnetic skyrmion lattice survives when removing a magnetic field, demonstrating its robustness. The work sheds light on an effective approach to nonvolatile and multistate control of 2D magnetic materials.

5.
Nano Lett ; 24(22): 6560-6567, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38775289

RESUMO

Kagome lattice AV3Sb5 has attracted tremendous interest because it hosts correlated and topological physics. However, an in-depth understanding of the temperature-driven electronic states in AV3Sb5 is elusive. Here we use scanning tunneling microscopy to directly capture the rotational symmetry-breaking effect in KV3Sb5. Through both topography and spectroscopic imaging of defect-free KV3Sb5, we observe a charge density wave (CDW) phase transition from an a0 × a0 atomic lattice to a robust 2a0 × 2a0 superlattice upon cooling the sample to 60 K. An individual Sb-atom vacancy in KV3Sb5 further gives rise to the local Friedel oscillation (FO), visible as periodic charge modulations in spectroscopic maps. The rotational symmetry of the FO tends to break at the temperature lower than 40 K. Moreover, the FO intensity shows an obvious competition against the intensity of the CDW. Our results reveal a tantalizing electronic nematicity in KV3Sb5, highlighting the multiorbital correlation in the kagome lattice framework.

6.
J Physiol ; 602(2): 317-332, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38152023

RESUMO

It has been documented that increased sympathetic activity contributes to the development of cardiovascular diseases, such as hypertension. We previously reported that ß-arrestin-1, a multifunctional cytoskeletal protein, was downregulated in the rostral ventrolateral medulla (RVLM) of the spontaneously hypertensive rat (SHR), and its overexpression elicited an inhibitory effect on sympathetic activity in hypertension. microRNA (miR)-22-3p has been reported to be associated with the pathological progress of hypertension. The purpose of this study was to determine the role of miR-22-3p in ß-arrestin-1-mediated central cardiovascular regulation in hypertension. It was observed that miR-22-3p was upregulated in the RVLM of SHRs compared with normotensive Wistar-Kyoto (WKY) rats, and it was subsequently confirmed to target the ß-arrestin-1 gene using a dual-luciferase reporter assay. miR-22-3p was downregulated in the RVLM using adeno-associated virus with 'tough decoys', which caused a significant increase of ß-arrestin-1 expression and decrease of noradrenaline and blood pressure (BP) in SHRs. However, upregulation of miR-22-3p using lentivirus in the RVLM of WKY rats significantly increased BP. In in vitro PC12 cells, enhanced oxidative stress activity induced by angiotensin II was counteracted by pretreatment with miR-22-3p inhibitor, and this effect could be abolished by ß-arrestin-1 gene knockdown. Furthermore, microglia exhaustion significantly diminished miR-22-3p expression, and enhanced ß-arrestin-1 expression in the RVLM of SHRs. Activation of BV2 cells in vitro evoked a significant increase of miR-22-3p expression, and this BV2 cell culture medium was also able to facilitate miR-22-3p expression in PC12 cells. Collectively, our findings support a critical role for microglia-derived miR-22-3p in inhibiting ß-arrestin-1 in the RVLM, which is involved in central cardiovascular regulation in hypertension. KEY POINTS: Impairment of ß-arrestin-1 function in the rostral ventrolateral medulla (RVLM) has been reported to be associated with the development of sympathetic overactivity in hypertension. However, little is known about the potential mechanisms of ß-arrestin-1 dysfunction in hypertension. miR-22-3p is implicated in multiple biological processes, but the role of miR-22-3p in central regulation of cardiovascular activity in hypertension remains unknown. We predicted that miR-22-3p could directly bind to the ß-arrestin-1 gene (Arrb1), and this hypothesis was confirmed by using a dual-luciferase reporter assay. Inhibition of ß-arrestin-1 by miR-22-3p was further verified in both in vivo and in vitro experiments. Furthermore, our results suggested miR-22-3p as a risk factor for oxidative stress in the RVLM, thus contributing to sympatho-excitation and hypertension. Our present study provides evidence that microglia-derived miR-22-3p may underlie the pathogenesis and progression of neuronal hypertension by inhibiting ß-arrestin-1 in the RVLM.


Assuntos
Hipertensão , MicroRNAs , Animais , Ratos , beta-Arrestina 1/genética , beta-Arrestina 1/metabolismo , Pressão Sanguínea/fisiologia , Luciferases/metabolismo , Bulbo/fisiologia , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
7.
J Am Chem Soc ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38512775

RESUMO

Despite their significant importance to numerous fields, the difficulties in direct and diverse synthesis of α-hydroxy-γ-lactams pose substantial obstacles to their practical applications. Here, we designed a nitrogen and TiO2 co-doped graphitic carbon-supported material with atomically dispersed cobalt sites (CoSA-N/NC-TiO2), which was successfully applied as a multifunctional catalyst to establish a general method for direct construction of α-hydroxy-γ-lactams from cheap and abundant nitro(hetero)arenes, aldehydes, and H2O with alkynoates. The striking features of operational simplicity, broad substrate and functionality compatibility (>100 examples), high step and atom efficiency, good selectivity, and exceptional catalyst reusability highlight the practicality of this new catalytic transformation. Mechanistic studies reveal that the active CoN4 species and the dopants exhibit a synergistic effect on the formation of key acid-masked nitrones; their subsequent nucleophilic addition to the alkynoates followed by successive reduction, alkenyl hydration, and intramolecular ester ammonolysis delivers the desired products. In this work, the concept of reduction interruption leading to new reaction route will open a door to further develop useful transformations by rational catalyst design.

8.
EMBO J ; 39(7): e103304, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32104923

RESUMO

Beneficial effects of resistance exercise on metabolic health and particularly muscle hypertrophy and fat loss are well established, but the underlying chemical and physiological mechanisms are not fully understood. Here, we identified a myometabolite-mediated metabolic pathway that is essential for the beneficial metabolic effects of resistance exercise in mice. We showed that substantial accumulation of the tricarboxylic acid cycle intermediate α-ketoglutaric acid (AKG) is a metabolic signature of resistance exercise performance. Interestingly, human plasma AKG level is also negatively correlated with BMI. Pharmacological elevation of circulating AKG induces muscle hypertrophy, brown adipose tissue (BAT) thermogenesis, and white adipose tissue (WAT) lipolysis in vivo. We further found that AKG stimulates the adrenal release of adrenaline through 2-oxoglutarate receptor 1 (OXGR1) expressed in adrenal glands. Finally, by using both loss-of-function and gain-of-function mouse models, we showed that OXGR1 is essential for AKG-mediated exercise-induced beneficial metabolic effects. These findings reveal an unappreciated mechanism for the salutary effects of resistance exercise, using AKG as a systemically derived molecule for adrenal stimulation of muscle hypertrophy and fat loss.


Assuntos
Ácidos Cetoglutáricos/sangue , Atrofia Muscular/genética , Receptores Purinérgicos P2/genética , Treinamento Resistido/métodos , Adulto , Idoso , Animais , Linhagem Celular , Feminino , Técnicas de Inativação de Genes , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Animais , Atrofia Muscular/metabolismo , Receptores Purinérgicos P2/metabolismo
9.
Biochem Biophys Res Commun ; 721: 150003, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38772212

RESUMO

BACKGROUND: In recent years, the incidence rate of nonalcoholic fatty liver disease (NAFLD) has ascended with the increasing number of metabolic diseases such as obesity and diabetes, which will bring great medical burden to society. At present, multiple scientific experiments have found that the CCR4-NOT complex can participate in regulating obesity and energy metabolism. This study is designed to explore the role and mechanism of CCR4-NOT transcription complex subunit 7 (CNOT7), a subunit of the CCR4-NOT complex in liver lipid deposition. METHODS: To establish the NAFLD cell model, palmitic acid (PA) was utilized to stimulate HepG2 cells and LO2 cells, promoting intracellular lipid deposition. CNOT7 was knockdown by siRNA and lentivirus to evaluate the effect of CNOT7 in NAFLD. RESULTS: Our results demonstrated that the expression of CNOT7 was increased in the NAFLD cell model. After knocking down CNOT7, the lipid deposition declined in HepG2 or LO2 cells treated by PA reduced. We found the lipid synthesis genes and the lipid uptake and transport factors in the CNOT7 knockdown group were significantly downregulated compared to the non-knockdown group. Furthermore, knockdown of CNOT7 might promote fatty acid oxidation. CONCLUSION: Knocking down CNOT7 can improve lipid deposition and CNOT7 may be a potential therapeutic target for NAFLD.


Assuntos
Metabolismo dos Lipídeos , Hepatopatia Gordurosa não Alcoólica , Humanos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/genética , Células Hep G2 , Técnicas de Silenciamento de Genes , Ácido Palmítico/metabolismo , Proteínas Repressoras/metabolismo , Proteínas Repressoras/genética , Fígado/metabolismo , Fígado/patologia , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Exorribonucleases
10.
Breast Cancer Res Treat ; 205(3): 545-554, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38472593

RESUMO

OBJECTIVE: To determine the risk of breast cancer due to lobular carcinoma in situ (LCIS). METHODS: This retrospective IRB-approved study identified cases of LCIS after percutaneous breast biopsy from 7/2005 to 7/2022. Excluded were cases with less than 2 years of imaging surveillance or a concurrent ipsilateral breast cancer diagnosis within 6 months of the LCIS diagnosis. Final outcomes of cancer versus no cancer were determined by pathology at surgical excision or the absence of cancer on imaging surveillance. RESULTS: A total of 116 LCIS lesions were identified. The primary imaging findings targeted for percutaneous biopsy included calcifications (50.0%, 58/116), MR enhancing lesions (25.0%, 29/116), noncalcified mammographic architectural distortions (10.3%, 12/116), or masses (14.7%, 17/116). Surgical excision was performed in 49.1% (57/116) and imaging surveillance was performed in 50.9% (59/116) of LCIS cases. There were 22 cancers of which 11 cancers were discovered at immediate excision [19.3% (11/57) immediate upgrade] and 11 cancers developed later while on imaging surveillance [18.6% (11/59) delayed risk for cancer]. Among all 22 cancers, 63.6% (14/22) occurred at the site of LCIS (11 at immediate excision and 3 at surveillance) and 36.4% (8/22) occurred at a location away from the site of LCIS (6 in a different quadrant and 2 in the contralateral breast). CONCLUSION: LCIS has both an immediate risk (19.3%) and a delayed risk (18.6%) for cancer with 90.9% occurring in the ipsilateral breast (63.6% at and 27.3% away from the site of LCIS) and 9.1% occurring in the contralateral breast.


Assuntos
Carcinoma de Mama in situ , Neoplasias da Mama , Carcinoma Lobular , Mamografia , Humanos , Feminino , Neoplasias da Mama/patologia , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Pessoa de Meia-Idade , Carcinoma de Mama in situ/patologia , Carcinoma de Mama in situ/diagnóstico por imagem , Carcinoma Lobular/patologia , Carcinoma Lobular/epidemiologia , Idoso , Estudos Retrospectivos , Adulto , Fatores de Risco , Idoso de 80 Anos ou mais
11.
J Virol ; 97(3): e0143322, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36916989

RESUMO

Cathelicidin antimicrobial peptides (mouse, CRAMP; human, LL-37) have broad-spectrum antiviral activities against enveloped viruses, but their mechanisms of action against nonenveloped viruses remain to be elucidated. Coxsackievirus B3 (CVB3), a member of nonenveloped virus belonging to the Enterovirus genus of Picornaviridae, is an important pathogen of viral myocarditis and dilated cardiomyopathy. Here, we observed that cardiac CRAMP expression was significantly upregulated in mice after CVB3 infection. The administration of CRAMP or LL-37 markedly suppressed CVB3 infection in mice, and CRAMP deficiency increased the susceptibility of mice to CVB3. CRAMP and LL-37 inhibited CVB3 replication in primary cardiomyocytes. However, they did not inactivate CVB3 particles and did not regulate the response of cardiomyocytes against CVB3 infection. Intriguingly, they inhibited CVB3 transmission through the exosome, but not virus receptor. In detail, CRAMP and LL-37 directly induced the lysis of exosomes by interfering with exosomal heat shock protein 60 (HSP60) and then blocked the diffusion of exosomes to recipient cells and inhibited the establishment of productive infection by exosomes. In addition, the interaction of CRAMP and LL-37 with HSP60 simultaneously inhibited HSP60-induced apoptosis in cardiomyocytes and reduced HSP60-enhanced CVB3 replication. Our findings reveal a novel mechanism of cathelicidins against viral infection and provide a new therapeutic strategy for CVB3-induced viral myocarditis. IMPORTANCE The relative mechanisms that cathelicidin antimicrobial peptides use to influence nonenveloped virus infection are unclear. We show here that cathelicidin antimicrobial peptides (CRAMP and LL-37) directly target exosomal HSP60 to destroy exosomes, which in turn block the diffusion of exosomes to recipient cardiomyocytes and reduced HSP60-induced apoptosis, thus restricting coxsackievirus B3 infection. Our results provide new insights into the mechanisms cathelicidin antimicrobial peptides use against viral infection.


Assuntos
Catelicidinas , Infecções por Coxsackievirus , Exossomos , Miócitos Cardíacos , Animais , Humanos , Camundongos , Apoptose/efeitos dos fármacos , Catelicidinas/administração & dosagem , Chaperonina 60/antagonistas & inibidores , Infecções por Coxsackievirus/tratamento farmacológico , Enterovirus Humano B/fisiologia , Exossomos/efeitos dos fármacos , Miocardite , Miócitos Cardíacos/efeitos dos fármacos , Replicação Viral
12.
Ann Surg Oncol ; 31(4): 2224-2230, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38117388

RESUMO

OBJECTIVE: The aim of this study was to determine surgical and clinical outcomes of lobular neoplasia (LN) diagnosed by magnetic resonance imaging (MRI) biopsy, including upgrade to malignancy, and to assess for characteristics associated with upgrade. METHOD: A single-institution retrospective study, between 2013 and 2022, of patients with histopathological findings of LN via MRI-guided biopsy was performed using an institutional database and review of the electronic medical records. Decision for excision or surveillance was made by a multidisciplinary team per institutional practice. Patient demographics and imaging characteristics were summarized using descriptive analyses. Upgrade was defined as upgrade to cancer on surgical pathology for patients treated with excision or the development of cancer at the biopsy site during surveillance. The Wilcoxon rank-sum test and Fisher's exact test were used to compare features of the upgraded cohort with the remainder of the group. RESULTS: Ninety-four MRI biopsies diagnosing LN were included. Median age was 57 years (range 37-78 years). Forty-six lesions underwent excision while 48 lesions were surveilled. The upgrade rate was 7.4% (7/94). Upgrades in the excised cohort consisted of pleomorphic lobular carcinoma in situ (LCIS; n = 1), ductal carcinoma in situ (DCIS; n = 3) and invasive lobular carcinoma (ILC; n = 2), while one interval development of DCIS was observed at the site of biopsy in the surveillance cohort. No MRI or patient variables were associated with upgrade. CONCLUSIONS: In this contemporary cohort of MRI-detected LNs, the upgrade rate was low. Omission of surgery for MRI-detected LNs in carefully selected patients may be considered in a shared decision-making capacity between the patient and the treatment team. Larger cohorts are needed to determine factors predictive of upgrade risk.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Carcinoma Lobular , Lesões Pré-Cancerosas , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/cirurgia , Estudos Retrospectivos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/cirurgia , Lesões Pré-Cancerosas/patologia , Biópsia Guiada por Imagem , Imageamento por Ressonância Magnética , Carcinoma Lobular/diagnóstico por imagem , Carcinoma Lobular/cirurgia , Biópsia com Agulha de Grande Calibre , Hiperplasia
13.
J Exp Bot ; 75(5): 1314-1330, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38069660

RESUMO

Sphingolipids are membrane lipids and play critical roles in signal transduction. Ceramides are central components of sphingolipid metabolism that are involved in cell death. However, the mechanism of ceramides regulating cell death in plants remains unclear. Here, we found that ceramides accumulated in mitochondria of accelerated cell death 5 mutant (acd5), and expression of mitochondrion-localized ceramide kinase (ACD5) suppressed mitochondrial ceramide accumulation and the acd5 cell death phenotype. Using immuno-electron microscopy, we observed hyperaccumulation of ceramides in acer acd5 double mutants, which are characterized by mutations in both ACER (alkaline ceramidase) and ACD5 genes. The results confirmed that plants with specific ceramide accumulation exhibited localization of ceramides to mitochondria, resulting in an increase in mitochondrial reactive oxygen species production. Interestingly, when compared with the wild type, autophagy-deficient mutants showed stronger resistance to ceramide-induced cell death. Lipid profiling analysis demonstrated that plants with ceramide accumulation exhibited a significant increase in phosphatidylethanolamine levels. Furthermore, exogenous ceramide treatment or endogenous ceramide accumulation induces autophagy. When exposed to exogenous ceramides, an increase in the level of the autophagy-specific ubiquitin-like protein, ATG8e, associated with mitochondria, where it directly bound to ceramides. Taken together, we propose that the accumulation of ceramides in mitochondria can induce cell death by regulating autophagy.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Ceramidas/metabolismo , Ceramidas/farmacologia , Arabidopsis/metabolismo , Mitocôndrias/metabolismo , Autofagia , Morte Celular , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo
14.
Chemistry ; 30(24): e202304373, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38282527

RESUMO

The in-depth study on reduction-specified coupling reactions of the nitroarenes by heterogeneous cobalt catalysis opens a door for diversified syntheses of functional N-containing molecules. Guided by the structure-function relationship of heterogeneous materials, rational design of nano-catalysts can effectively regulate the routes of organic reactions. Precise transformation of the intermediates generated during the nitroarene reduction with a suitable nano-catalyst is a promising way to develop new tandem reactions, and to synthesize structurally novel compounds that are of difficult access with the conventional approaches.

15.
Chemistry ; 30(18): e202303973, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38179822

RESUMO

As a multifunctional material, metal clusters have recently received some attention for their application in solar cells.This review delves into the multifaceted role of metal clusters in advancing solar cell technologies, covering diverse aspects from electron transport and interface modification to serving as molecular precursors for inorganic materials and acting as photosensitizers in metal-cluster sensitized solar cells (MCSSCs). The studies conducted by various researchers illustrate the crucial impact of metal clusters, such as gold nanoclusters (Au NCs), on enhancing solar cell efficiency through size-dependent effects, distinct interface behaviors, and tailored interface engineering. From optimizing charge transfer rates to improving light absorption and reducing carrier recombination, metal clusters prove instrumental in shaping the landscape of solar energy conversion.The promising performance of metal-cluster sensitized solar cells, coupled with their scalability and flexibility, positions them as a exciting avenue for future clean energy applications. The article concludes by emphasizing the need for continued interdisciplinary research and technological innovation to unlock the full potential of metal clusters in contributing to sustainable and high-performance solar cells.

16.
Brain Behav Immun ; 115: 179-190, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37848098

RESUMO

The decline in gut microbial diversity in modern humans is closely associated with the rising prevalence of various diseases. It is imperative to investigate the underlying causes of gut microbial loss and restoring methods. Although the impact of non-perinatal antibiotic use on gut microbiota has been recognized, its intergenerational effects remain unexplored. Our previous research has highlighted soil in the farm environment as a key factor for gut microbiome health by restoring gut microbial diversity and balance. In this study, we investigated the intergenerational consequences of antibiotic exposure and the therapeutic potential of sterile soil. We treated C57BL/6 mice with vancomycin and streptomycin for 2 weeks continuously, followed by a 4-8 week withdrawal period before breeding. The process was repeated across 3 generations. Half of the mice in each generation received an oral sterile soil intervention. We assessed gut microbial diversity, anxiety behavior, microglial reactivity, and gut barrier integrity across generations. Antibiotic exposure led to a decrease in gut microbial diversity over generations, along with aggravated anxiety behavior, microgliosis, and altered intestinal tight junction protein expression. Oral sterile soil intervention restored gut microbial diversity in adult mice across generations, concomitantly rescuing abnormalities in behavior, microgliosis, and intestinal barrier integrity. In conclusion, this study simulated an important process of the progressive loss of gut microbiota diversity in modern humans and demonstrated the potential of sterile soil to reverse this process. This study provides a theoretical and experimental basis for research and interventions targeting multiple modern chronic diseases related to intestinal microorganisms.


Assuntos
Antibacterianos , Microbioma Gastrointestinal , Humanos , Animais , Camundongos , Antibacterianos/farmacologia , Solo , Camundongos Endogâmicos C57BL
17.
Mol Psychiatry ; 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38001338

RESUMO

The hypothalamus plays a crucial role in controlling metabolism and energy balance, with Agouti-related protein (AgRP) neurons and proopiomelanocortin (POMC) neurons being essential components of this process. The proper development of these neurons is important for metabolic regulation in later life. Microglia, the resident immune cells in the brain, have been shown to significantly influence neurodevelopment. However, their role in shaping the postnatal development of hypothalamic neural circuits remains underexplored. In this study, we investigated the dynamic changes of microglia in the hypothalamic arcuate nucleus (ARC) during lactation and their impact on the maturation of AgRP and POMC neurons. We demonstrated that microglial depletion during a critical period of ARC neuron maturation increases the number of AgRP neurons and fiber density, with less effect on POMC neurons. This depletion also resulted in increased neonatal feeding behavior. Mechanistically, microglia can engulf perineuronal net (PNN) components surrounding AgRP neurons both in vivo and ex vivo. The absence of microglia leads to increased PNN formation and enhanced leptin sensitivity in ARC. Our findings suggest that microglia participate in the postnatal development of AgRP neurons by regulating the plasticity of PNN formation. This study contributes to a better understanding of microglia's role in shaping hypothalamic neural circuits during postnatal development and their impact on metabolism regulation.

18.
Immunity ; 43(2): 304-17, 2015 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-26253786

RESUMO

Antimicrobial peptides (AMPs) expressed by epithelial and immune cells are largely described for the defense against invading microorganisms. Recently, their immunomodulatory functions have been highlighted in various contexts. However how AMPs expressed by non-immune cells might influence autoimmune responses in peripheral tissues, such as the pancreas, is unknown. Here, we found that insulin-secreting ß-cells produced the cathelicidin related antimicrobial peptide (CRAMP) and that this production was defective in non-obese diabetic (NOD) mice. CRAMP administrated to prediabetic NOD mice induced regulatory immune cells in the pancreatic islets, dampening the incidence of autoimmune diabetes. Additional investigation revealed that the production of CRAMP by ß-cells was controlled by short-chain fatty acids produced by the gut microbiota. Accordingly, gut microbiota manipulations in NOD mice modulated CRAMP production and inflammation in the pancreatic islets, revealing that the gut microbiota directly shape the pancreatic immune environment and autoimmune diabetes development.


Assuntos
Catelicidinas/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/imunologia , Intestinos/imunologia , Microbiota/fisiologia , Pâncreas/imunologia , Animais , Peptídeos Catiônicos Antimicrobianos , Catelicidinas/genética , Diabetes Mellitus Tipo 1/microbiologia , Ácidos Graxos Voláteis/imunologia , Feminino , Intestinos/microbiologia , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Camundongos Knockout , Pâncreas/microbiologia
19.
Physiol Plant ; 176(2): e14271, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566130

RESUMO

Seed dormancy is an important life history state in which intact viable seeds delay or prevent germination under suitable conditions. Ascorbic acid (AsA) acts as a small molecule antioxidant, and breaking seed dormancy and promoting subsequent growth are among its numerous functions. In this study, a germination test using Pyrus betulifolia seeds treated with exogenous AsA or AsA synthesis inhibitor lycorine (Lyc) and water absorption was conducted. The results indicated that AsA released dormancy and increased germination and 20 mmol L-1 AsA promoted cell division, whereas Lyc reduced germination. Seed germination showed typical three phases of water absorption; and seeds at five key time points were sampled for transcriptome analysis. It revealed that multiple pathways were involved in breaking dormancy and promoting germination through transcriptome data, and 12 differentially expressed genes (DEGs) related to the metabolism and signal transduction of abscisic acid (ABA) and gibberellins (GA) were verified by subsequent RT-qPCR. For metabolites, exogenous AsA increased endogenous AsA and GA3 but reduced ABA and the ABA/GA3 ratio. In addition, three genes regulating ABA synthesis were downregulated by AsA, while five genes mediating ABA degradation were upregulated. Taken together, AsA regulates the pathways associated with ABA and GA synthesis, catalysis, and signal transduction, with subsequent reduction in ABA and increase in GA and further the balance of ABA/GA, ultimately releasing dormancy and promoting germination.


Assuntos
Giberelinas , Pyrus , Giberelinas/farmacologia , Giberelinas/metabolismo , Ácido Abscísico/farmacologia , Ácido Abscísico/metabolismo , Germinação , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Pyrus/metabolismo , Ácido Ascórbico/metabolismo , Dormência de Plantas/genética , Sementes , Água/metabolismo , Regulação da Expressão Gênica de Plantas
20.
BMC Infect Dis ; 24(1): 200, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38355468

RESUMO

BACKGROUND: A lack of health resources is a common problem after the outbreak of infectious diseases, and resource optimization is an important means to solve the lack of prevention and control capacity caused by resource constraints. This study systematically evaluated the similarities and differences in the application of coronavirus disease (COVID-19) resource allocation models and analyzed the effects of different optimal resource allocations on epidemic control. METHODS: A systematic literature search was conducted of CNKI, WanFang, VIP, CBD, PubMed, Web of Science, Scopus and Embase for articles published from January 1, 2019, through November 23, 2023. Two reviewers independently evaluated the quality of the included studies, extracted and cross-checked the data. Moreover, publication bias and sensitivity analysis were evaluated. RESULTS: A total of 22 articles were included for systematic review; in the application of optimal allocation models, 59.09% of the studies used propagation dynamics models to simulate the allocation of various resources, and some scholars also used mathematical optimization functions (36.36%) and machine learning algorithms (31.82%) to solve the problem of resource allocation; the results of the systematic review show that differential equation modeling was more considered when testing resources optimization, the optimization function or machine learning algorithm were mostly used to optimize the bed resources; the meta-analysis results showed that the epidemic trend was obviously effectively controlled through the optimal allocation of resources, and the average control efficiency was 0.38(95%CI 0.25-0.51); Subgroup analysis revealed that the average control efficiency from high to low was health specialists 0.48(95%CI 0.37-0.59), vaccines 0.47(95%CI 0.11-0.82), testing 0.38(95%CI 0.19-0.57), personal protective equipment (PPE) 0.38(95%CI 0.06-0.70), beds 0.34(95%CI 0.14-0.53), medicines and equipment for treatment 0.32(95%CI 0.12-0.51); Funnel plots and Egger's test showed no publication bias, and sensitivity analysis suggested robust results. CONCLUSION: When the data are insufficient and the simulation time is short, the researchers mostly use the constructor for research; When the data are relatively sufficient and the simulation time is long, researchers choose differential equations or machine learning algorithms for research. In addition, our study showed that control efficiency is an important indicator to evaluate the effectiveness of epidemic prevention and control. Through the optimization of medical staff and vaccine allocation, greater prevention and control effects can be achieved.


Assuntos
COVID-19 , Epidemias , Humanos , COVID-19/epidemiologia , Equipamento de Proteção Individual , SARS-CoV-2 , Surtos de Doenças
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