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1.
Nature ; 604(7907): 763-770, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418678

RESUMO

Adhesion G-protein-coupled receptors (aGPCRs) are important for organogenesis, neurodevelopment, reproduction and other processes1-6. Many aGPCRs are activated by a conserved internal (tethered) agonist sequence known as the Stachel sequence7-12. Here, we report the cryogenic electron microscopy (cryo-EM) structures of two aGPCRs in complex with Gs: GPR133 and GPR114. The structures indicate that the Stachel sequences of both receptors assume an α-helical-bulge-ß-sheet structure and insert into a binding site formed by the transmembrane domain (TMD). A hydrophobic interaction motif (HIM) within the Stachel sequence mediates most of the intramolecular interactions with the TMD. Combined with the cryo-EM structures, biochemical characterization of the HIM motif provides insight into the cross-reactivity and selectivity of the Stachel sequences. Two interconnected mechanisms, the sensing of Stachel sequences by the conserved 'toggle switch' W6.53 and the constitution of a hydrogen-bond network formed by Q7.49/Y7.49 and the P6.47/V6.47φφG6.50 motif (φ indicates a hydrophobic residue), are important in Stachel sequence-mediated receptor activation and Gs coupling. Notably, this network stabilizes kink formation in TM helices 6 and 7 (TM6 and TM7, respectively). A common Gs-binding interface is observed between the two aGPCRs, and GPR114 has an extended TM7 that forms unique interactions with Gs. Our structures reveal the detailed mechanisms of aGPCR activation by Stachel sequences and their Gs coupling.


Assuntos
Peptídeos , Receptores Acoplados a Proteínas G , Sítios de Ligação , Microscopia Crioeletrônica , Domínios Proteicos , Estrutura Secundária de Proteína , Receptores Acoplados a Proteínas G/metabolismo , Relação Estrutura-Atividade
2.
Dev Biol ; 512: 57-69, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38750688

RESUMO

Understanding the developmental processes and signaling pathways involved in larval myogenesis and metamorphosis is crucial for comprehending the life history and adaptive strategies of marine organisms. In this study, we investigated the temporal and spatial patterns of myogenesis in the mussel Mytilus coruscus (Mc), focusing on the emergence and transformation of major muscle groups during different larval stages. We also explored the role of the Hedgehog (Hh) signaling pathway in regulating myogenesis and larval metamorphosis. The results revealed distinct developmental stages characterized by the emergence of specific muscular components, such as velum retractor muscles and anterior adductor muscles, in D-veliger and umbo larvae, which are responsible for the planktonic stage. In the pediveliger stage, posterior ventral, posterior adductor, and foot muscles appeared. After larval metamorphosis, the velum structure and its corresponding retractor muscles degenerate, indicating the transition from planktonic to benthic life. We observed a conserved pattern of larval musculature development and revealed a high degree of conservation across bivalve species, with comparable emergence times during myogenesis. Furthermore, exposure to the Hh signaling inhibitor cyclopamine impaired larval muscle development, reduced larval swimming activity, and inhibited larval metamorphosis in M. coruscus. Cyclopamine-mediated inhibition of Hh signaling led to reduced expression of four key genes within the Hh signaling pathway (McHh, McPtc, McSmo, and McGli) and the striated myosin heavy chain gene (McMHC). It is hypothesised that the abnormal larval muscle development in cyclopamine-treated groups may be an indirect effect due to disrupted McMHC expression. We provide evidence for the first time that cyclopamine treatment inhibited larval metamorphosis in bivalves, highlighting the potential involvement of Hh signaling in mediating larval muscle development and metamorphosis in M. coruscus. The present study provides insights into the dynamic nature of myogenesis and the regulatory role of the Hh signaling pathway during larval development and metamorphosis in M. coruscus. The results obtained in this study contribute to a better understanding of the evolutionary significance of Hh signaling in bivalves and shed light on the mechanisms underlying larval muscle development and metamorphosis in marine invertebrates.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Proteínas Hedgehog , Larva , Metamorfose Biológica , Desenvolvimento Muscular , Mytilus , Transdução de Sinais , Animais , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Mytilus/crescimento & desenvolvimento , Mytilus/metabolismo , Alcaloides de Veratrum/farmacologia , Músculos/metabolismo
3.
Nano Lett ; 24(17): 5308-5316, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38647008

RESUMO

FAPbI3 stands out as an ideal candidate for the photoabsorbing layer of perovskite solar cells (PSCs), showcasing outstanding photovoltaic properties. Nonetheless, stabilizing photoactive α-FAPbI3 remains a challenge due to the lower formation energy of the competitive photoinactive δ-phase. In this study, we employ tetraethylphosphonium lead tribromide (TEPPbBr3) single crystals as templates for the epitaxial growth of PbI2. The strategic use of TEPPbBr3 optimizes the evolution of intermediates and the crystallization kinetics of perovskites, leading to high-quality and phase-stable α-FAPbI3 films. The TEPPbBr3-modified perovskite exhibits optimized carrier dynamics, yielding a champion efficiency of 25.13% with a small voltage loss of 0.34 V. Furthermore, the target device maintains 90% of its initial PCE under maximum power point (MPP) tracking over 1000 h. This work establishes a promising pathway through single crystal seed based epitaxial growth for achieving satisfactory crystallization regulation and phase stabilization of α-FAPbI3 perovskites toward high-efficiency and stable PSCs.

4.
J Am Chem Soc ; 146(28): 18967-18978, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38973592

RESUMO

Platensilin, platensimycin, and platencin are potent inhibitors of ß-ketoacyl-acyl carrier protein synthase (FabF) in the bacterial and mammalian fatty acid synthesis system, presenting promising drug leads for both antibacterial and antidiabetic therapies. Herein, a bioinspired skeleton reconstruction approach is reported, which enables the unified synthesis of these three natural FabF inhibitors and their skeletally diverse analogs, all stemming from a common ent-pimarane core. The synthesis features a diastereoselective biocatalytic reduction and an intermolecular Diels-Alder reaction to prepare the common ent-pimarane core. From this intermediate, stereoselective Mn-catalyzed hydrogen atom-transfer hydrogenation and subsequent Cu-catalyzed carbenoid C-H insertion afford platensilin. Furthermore, the intramolecular Diels-Alder reaction succeeded by regioselective ring opening of the newly formed cyclopropane enables the construction of the bicyclo[3.2.1]-octane and bicyclo[2.2.2]-octane ring systems of platensimycin and platencin, respectively. This skeletal reconstruction approach of the ent-pimarane core facilitates the preparation of analogs bearing different polycyclic scaffolds. Among these analogs, the previously unexplored cyclopropyl analog 47 exhibits improved antibacterial activity (MIC80 = 0.0625 µg/mL) against S. aureus compared to platensimycin.


Assuntos
Adamantano , Aminobenzoatos , Aminofenóis , Anilidas , Compostos Policíclicos , Aminofenóis/química , Aminofenóis/farmacologia , Aminofenóis/síntese química , Compostos Policíclicos/química , Compostos Policíclicos/farmacologia , Compostos Policíclicos/síntese química , Adamantano/química , Adamantano/farmacologia , Adamantano/síntese química , Adamantano/análogos & derivados , Anilidas/farmacologia , Anilidas/química , Anilidas/síntese química , Aminobenzoatos/farmacologia , Aminobenzoatos/química , Aminobenzoatos/síntese química , Antibacterianos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Estrutura Molecular , Reação de Cicloadição , Testes de Sensibilidade Microbiana , Estereoisomerismo , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química
5.
Crit Rev Biotechnol ; 44(3): 337-351, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-36779332

RESUMO

ß-Carotene is one kind of the most important carotenoids. The major functions of ß-carotene include the antioxidant and anti-cardiovascular properties, which make it a growing market. Recently, the use of metabolic engineering to construct microbial cell factories to synthesize ß-carotene has become the latest model for its industrial production. Among these cell factories, yeasts including Saccharomyces cerevisiae and Yarrowia lipolytica have attracted the most attention because of the: security, mature genetic manipulation tools, high flux toward carotenoids using the native mevalonate pathway and robustness for large-scale fermentation. In this review, the latest strategies for ß-carotene biosynthesis, including protein engineering, promoters engineering and morphological engineering are summarized in detail. Finally, perspectives for future engineering approaches are proposed to improve ß-carotene production.


Assuntos
Engenharia Metabólica , Yarrowia , beta Caroteno/genética , beta Caroteno/metabolismo , Yarrowia/genética , Yarrowia/metabolismo , Saccharomyces cerevisiae/genética , Regiões Promotoras Genéticas
6.
Crit Rev Biotechnol ; : 1-16, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38705840

RESUMO

5-Aminolevulinic acid (5-ALA) is a non-proteinogenic amino acid essential for synthesizing tetrapyrrole compounds, including heme, chlorophyll, cytochrome, and vitamin B12. As a plant growth regulator, 5-ALA is extensively used in agriculture to enhance crop yield and quality. The complexity and low yield of chemical synthesis methods have led to significant interest in the microbial synthesis of 5-ALA. Advanced strategies, including the: enhancement of precursor and cofactor supply, compartmentalization of key enzymes, product transporters engineering, by-product formation reduction, and biosensor-based dynamic regulation, have been implemented in bacteria for 5-ALA production, significantly advancing its industrialization. This article offers a comprehensive review of recent developments in 5-ALA production using engineered bacteria and presents new insights to propel the field forward.

7.
Nat Chem Biol ; 18(11): 1196-1203, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35982227

RESUMO

Adhesion G protein-coupled receptors are elusive in terms of their structural information and ligands. Here, we solved the cryogenic-electron microscopy (cryo-EM) structure of apo-ADGRG2, an essential membrane receptor for maintaining male fertility, in complex with a Gs trimer. Whereas the formations of two kinks were determinants of the active state, identification of a potential ligand-binding pocket in ADGRG2 facilitated the screening and identification of dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate and deoxycorticosterone as potential ligands of ADGRG2. The cryo-EM structures of DHEA-ADGRG2-Gs provided interaction details for DHEA within the seven transmembrane domains of ADGRG2. Collectively, our data provide a structural basis for the activation and signaling of ADGRG2, as well as characterization of steroid hormones as ADGRG2 ligands, which might be used as useful tools for further functional studies of the orphan ADGRG2.


Assuntos
Receptores Acoplados a Proteínas G , Transdução de Sinais , Humanos , Masculino , Microscopia Crioeletrônica , Sulfato de Desidroepiandrosterona , Desoxicorticosterona , Ligantes , Receptores Acoplados a Proteínas G/química
8.
Clin Exp Rheumatol ; 42(2): 237-245, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38153165

RESUMO

OBJECTIVES: Anti-MDA5+ dermatomyositis was associated with poor prognosis due to the high incidence of rapid progressive interstitial lung disease, pulmonary infection. The aim of this study is to investigate the abundance and clinical relevance of exhaustion markers on peripheral CD8 T cells from patients with idiopathic inflammatory myopathy (IIM). METHODS: Twenty-nine healthy controls (HCs) and 71 patients with IIM were enrolled, including 42 with anti-MDA5+ and 18 with anti-MDA5- dermatomyositis (DM) and 11 with anti-synthetase syndrome (ASS). Flow cytometry was applied to detect PD-1, TIM-3 and LAG-3 in CD8 T cells. The clinical associations of the CD8 T cell exhaustion phenotype in patients with anti-MDA5+ DM were analysed. RESULTS: CD8 T cells from patients with anti-MDA5+ DM showed significantly increased LAG-3, TIM-3 and PD-1 compared to those from patients with anti-MDA5- IIM (18 with anti-MDA5- DM and 11 with ASS) or HCs (adjusted p all < 0.05). CD8 T cells with distinct exhaustion levels were all significantly increased in anti-MDA5+ DM patients compared with HCs (p all < 0.05). Patients with high level of PD-1+ TIM-3+LAG-3+ CD8+ T cells had a significant higher incidence of pulmonary fungal infections but lower counts of CD4+ and CD8+ T cells. ROC analysis revealed that the frequency of PD-1+TIM-3+LAG-3+CD8+ T cell significantly predicted pulmonary fungal infections (area under the curve: 0.828). CONCLUSIONS: CD8 T cells from patients with anti-MDA5+ DM show significant exhausted phenotype, and increased exhausted CD8 T cells were associated with high risk of pulmonary fungal infection.


Assuntos
Dermatomiosite , Humanos , Dermatomiosite/complicações , Receptor Celular 2 do Vírus da Hepatite A , Helicase IFIH1 Induzida por Interferon , Receptor de Morte Celular Programada 1 , Autoanticorpos , Linfócitos T CD8-Positivos , Linfócitos T , Estudos Retrospectivos , Prognóstico
9.
Exp Cell Res ; 431(1): 113738, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37572787

RESUMO

Epithelial-mesenchymal transition (EMT) plays a critical role in hypertension-induced renal fibrosis, a final pathway that leads to end-stage renal failure. C-Atrial natriuretic peptide (ANP)4-23, a specific agonist of natriuretic peptide receptor-C (NPR-C), has been reported to have protective effects against hypertension. However, the role of C-ANP4-23 in hypertension-associated renal fibrosis has not yet been elucidated. In this study, mice were randomly divided into SHAM group, DOCA-salt group and DOCA-salt + C-ANP4-23 group. Renal morphology changes, renal function and fibrosis were detected. Human proximal tubular epithelial cells (HK2) stimulated by aldosterone were used for cell function and mechanism study. The DOCA-salt treated mice exhibited hypertension, kidney fibrosis and renal dysfunction, which were attenuated by C-ANP4-23. Moreover, C-ANP4-23 inhibited DOCA-salt treatment-induced renal EMT as evidenced by decrease of the mesenchymal marker alpha-smooth muscle actin (ACTA2) and vimentin and increase of epithelial cell marker E-cadherin. In HK2 cells, aldosterone induced EMT response, which was also suppressed by C-ANP4-23. The key transcription factors (twist, snail, slug and ZEB1) involved in EMT were increased in the kidney of DOCA-salt-treated mice, which were also suppressed by C-ANP4-23. Mechanistically, C-ANP4-23 inhibited the aldosterone-induced translocation of MR from cytosol to nucleus without change of MR expression. Furthermore, C-ANP4-23 rescued the enhanced expression of NADPH oxidase (NOX) 4 and oxidative stress after aldosterone stimulation. Aldosterone-induced Akt and Erk1/2 activation was also suppressed by C-ANP4-23. Our data suggest that C-ANP4-23 attenuates renal fibrosis, likely through inhibition of MR activation, enhanced oxidative stress and Akt and Erk1/2 signaling pathway.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão , Nefropatias , Camundongos , Humanos , Animais , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Receptores do Fator Natriurético Atrial/metabolismo , Aldosterona/efeitos adversos , Aldosterona/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Acetato de Desoxicorticosterona/efeitos adversos , Hipertensão/induzido quimicamente , Hipertensão/metabolismo , Rim/metabolismo , Nefropatias/induzido quimicamente , Nefropatias/prevenção & controle , Acetatos/efeitos adversos , Acetatos/metabolismo , Fibrose
10.
Molecules ; 29(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38792186

RESUMO

Thrombotic disease has been listed as the third most fatal vascular disease in the world. After decades of development, clinical thrombolytic drugs still cannot avoid the occurrence of adverse reactions such as bleeding. A number of studies have shown that the application of various nano-functional materials in thrombus-targeted drug delivery, combined with external stimuli, such as magnetic, near-infrared light, ultrasound, etc., enrich the drugs in the thrombus site and use the properties of nano-functional materials for collaborative thrombolysis, which can effectively reduce adverse reactions such as bleeding and improve thrombolysis efficiency. In this paper, the research progress of organic nanomaterials, inorganic nanomaterials, and biomimetic nanomaterials for drug delivery is briefly reviewed.


Assuntos
Sistemas de Liberação de Medicamentos , Fibrinolíticos , Trombose , Humanos , Fibrinolíticos/química , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Trombose/tratamento farmacológico , Nanoestruturas/química , Nanoestruturas/uso terapêutico , Terapia Trombolítica/métodos , Animais
11.
Molecules ; 29(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38893339

RESUMO

Six ionone glycosides (1-3 and 5-7), including three new ones, named capitsesqsides A-C (1-3), together with an eudesmane sesquiterpenoid glycoside (4) and three known triterpenoid saponins (8-10) were isolated from Rhododendron capitatum. The structures of these compounds were determined by extensive spectroscopic techniques (MS, UV, 1D-NMR, and 2D-NMR) and comparison with data reported in the literature. The absolute configurations were determined by comparison of the experimental and theoretically calculated ECD curves and LC-MS analyses after acid hydrolysis and derivatization. The anti-inflammatory activities of these compounds were evaluated in the LPS-induced RAW264.7 cells. Molecular docking demonstrated that 2 has a favorable affinity for NLRP3 and iNOS.


Assuntos
Glicosídeos , Rhododendron , Rhododendron/química , Camundongos , Glicosídeos/química , Glicosídeos/farmacologia , Glicosídeos/isolamento & purificação , Células RAW 264.7 , Animais , Simulação de Acoplamento Molecular , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Norisoprenoides/química , Norisoprenoides/farmacologia , Norisoprenoides/isolamento & purificação , Estrutura Molecular , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Lipopolissacarídeos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia
12.
Geriatr Nurs ; 58: 290-297, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38848610

RESUMO

OBJECTIVE: To systematically evaluate the current status of apathy in dementia patients and its associated factors. METHODS: We searched Chinese and English databases to collect studies on the associated factors of apathy in patients with dementia from inception to March 14, 2023. Two researchers independently screened the literature, evaluated the quality, and extracted the data RESULTS: A total of 20 studies were included, and the incidence of apathy in patients with dementia ranged from 21 % to 90 %. According to the model of apathy proposed by Massimo in 2018, the associated factors were divided into individual factors for dementia patients, caregiver factors, and environmental factors. The individual factors of apathy in patients with dementia mainly include demographic characteristics, the severity of cognitive impairment, a combination of other behavioral and psychological symptoms of dementia, acute medical problems or adverse drug reactions, unmet needs, and malnutrition. Caregiver factors mainly include emotional expressions of hostility or criticism towards dementia patients and caregivers' expectations for a better life in the future. Environmental factors mainly include too high or too low stimulation and a lack of daytime activities CONCLUSIONS: Existing studies have shown that the incidence of apathy in dementia patients is high and is affected by multi-dimensional factors. There are more studies on individual factors in dementia patients and fewer studies on caregivers and environmental factors. In the future, a large number of high-quality studies are needed to demonstrate the mechanism of apathy in dementia patients and to find more related factors.

13.
Zhongguo Zhong Yao Za Zhi ; 49(4): 1113-1121, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621918

RESUMO

This study systematically collected, analyzed, and evaluated randomized controlled trial(RCT) in the treatment of diabetic foot ulcer(DFU). The aim as provide references for future studies and to enhance the application of clinical evidence. The RCT of DFU treated with Chinese Patent Medicine was obtained and analyzed using the AI-Clinical Evidence Database of Chinese Patent Medicine(AICED-CPM). The analysis was supplemented with data from CNKI, Wanfang, VIP, SinoMed, PubMed, EMbase, Cochrane Library, and Web of Science. A total of 275 RCTs meeting the requirements were retrieved, with only 7 of them having a sample size of 200 or more. These trials involved 66 different Chinese patent medicine including 25 oral medications, 24 Chinese herbal injections, and 17 external drugs. Among the 33 different intervention/control designs identified, the most common design was Chinese patent medicine + conventional treatment vs conventional treatment(86 cases, 31.27%). Out of the 275 articles included in the literature, 50 did not provide information on the specific course of treatment(18.18%). A total of 10 counting indicators(with a frequency of 426) and 36 measuring indicators(with a frequency of 962) were utilized. The methodological quality of the RCT for the treatment of DFU with Chinese patent medicine was found to be low, with deficiencies in blind methods, other bias factors, study registration, and sample size estimation. There were noticeable shortcomings in the reporting of allocation hiding and implementation bias(blind method application). More studies should prioritize trial registration, program design, and strict quality control during implementation to provide valuable data for clinical practice and serve as a reference for future investigations.


Assuntos
Diabetes Mellitus , Pé Diabético , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Diabetes Mellitus/tratamento farmacológico , Pé Diabético/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos sem Prescrição/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
14.
Am J Physiol Cell Physiol ; 325(4): C1106-C1118, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37746698

RESUMO

Sarcolemmal ATP-sensitive potassium (KATP) channels play a vital role in cardioprotection. Cardiac KATP channels are enriched in caveolae and physically interact with the caveolae structural protein caveolin-3 (Cav3). Disrupting caveolae impairs the regulation of KATP channels through several signaling pathways. However, the direct functional effect of Cav3 on KATP channels is still poorly understood. Here, we used the cardiac KATP channel subtype, Kir6.2/SUR2A, and showed that Cav3 greatly reduced KATP channel surface density and current amplitude in a caveolae-independent manner. A screen of Cav3 functional domains revealed that a 25 amino acid region in the membrane attachment domain of Cav3 is the minimal effective segment (MAD1). The peptide corresponding to the MAD1 segment decreased KATP channel current in a concentration-dependent manner with an IC50 of ∼5 µM. The MAD1 segment prevented KATP channel recycling, thus decreasing KATP channel surface density and abolishing the cardioprotective effect of ischemic preconditioning. Our research identified the Cav3 MAD1 segment as a novel negative regulator of KATP channel recycling, providing pharmacological potential in the treatment of diseases with KATP channel trafficking defects.NEW & NOTEWORTHY Cardiac KATP channels physically interact with caveolin-3 in caveolae. In this study, we investigated the functional effect of caveolin-3 on KATP channel activity and identified a novel segment (MAD1) in the C-terminus domain of Caveolin-3 that negatively regulates KATP channel surface density and current amplitude by impairing KATP channel recycling. The peptide corresponding to the MAD1 segment abolished the cardioprotective effect of ischemic preconditioning.

15.
Opt Lett ; 48(7): 1626-1629, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221726

RESUMO

The study of all-group-IV SiGeSn lasers has opened a new avenue to Si-based light sources. SiGeSn heterostructure and quantum well lasers have been successfully demonstrated in the past few years. It has been reported that, for multiple quantum well lasers, the optical confinement factor plays an important role in the net modal gain. In previous studies, adding a cap layer was proposed to increase the optical mode overlap with the active region and thereby improve the optical confinement factor of Fabry-Perot cavity lasers. In this work, SiGeSn/GeSn multiple quantum well (4-well) devices with various cap layer thicknesses, i.e., 0 (no cap), 190, 250, and 290 nm, are grown using a chemical vapor deposition reactor and characterized via optical pumping. While no-cap and thinner-cap devices only show spontaneous emission, the two thicker-cap devices exhibit lasing up to 77 K, with an emission peak at 2440 nm and a threshold of 214 kW/cm2 (250 nm cap device). The clear trend in device performance disclosed in this work provides guidance in device design for electrically injected SiGeSn quantum well lasers.

16.
Mol Psychiatry ; 27(1): 19-33, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34580416

RESUMO

Infectious diseases, including COVID-19, are crucial public health issues and may lead to considerable fear among the general public and stigmatization of, and discrimination against, specific populations. This meta-analysis aimed to estimate the pooled prevalence of stigma in infectious disease epidemics. We systematically searched PubMed, PsycINFO, Embase, MEDLINE, Web of Science, and Cochrane databases since inception to June 08, 2021, and reported the prevalence of stigma towards people with infectious diseases including SARS, H1N1, MERS, Zika, Ebola, and COVID-19. A total of 50 eligible articles were included that contributed 51 estimates of prevalence in 92722 participants. The overall pooled prevalence of stigma across all populations was 34% [95% CI: 28-40%], including enacted stigma (36% [95% CI: 28-44%]) and perceived stigma (31% [95% CI: 22-40%]). The prevalence of stigma in patients, community population, and health care workers, was 38% [95% CI: 12- 65%], 36% [95% CI: 28-45%], and 30% [95% CI: 20-40%], respectively. The prevalence of stigma in participants from low- and middle-income countries was 37% [95% CI: 29-45%], which is higher than that from high-income countries (27% [95% CI: 18-36%]) though this difference was not statistically significant. A similar trend of prevalence of stigma was also observed in individuals with lower education (47% [95% CI: 23-71%]) compared to higher education level (33% [95% CI: 23-4%]). These findings indicate that stigma is a significant public health concern, and effective and comprehensive interventions are needed to counteract the damaging effects of the infodemics during infectious disease epidemics, including COVID-19, and reduce infectious disease-related stigma.


Assuntos
COVID-19 , Doenças Transmissíveis , Vírus da Influenza A Subtipo H1N1 , Infecção por Zika virus , Zika virus , Humanos , Prevalência
17.
Mol Psychiatry ; 27(8): 3214-3222, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35668158

RESUMO

Infectious disease epidemics have become more frequent and more complex during the 21st century, posing a health threat to the general public and leading to psychological symptoms. The current study was designed to investigate the prevalence of and risk factors associated with depression, anxiety and insomnia symptoms during epidemic outbreaks, including COVID-19. We systematically searched the PubMed, Embase, Web of Science, OVID, Medline, Cochrane databases, bioRxiv and medRxiv to identify studies that reported the prevalence of depression, anxiety or insomnia during infectious disease epidemics, up to August 14th, 2020. Prevalence of mental symptoms among different populations including the general public, health workers, university students, older adults, infected patients, survivors of infection, and pregnant women across all types of epidemics was pooled. In addition, prevalence of mental symptoms during COVID-19 was estimated by time using meta-regression analysis. A total of 17,506 papers were initially retrieved, and a final of 283 studies met the inclusion criteria, representing a total of 948,882 individuals. The pooled prevalence of depression ranged from 23.1%, 95% confidential intervals (95% CI: [13.9-32.2]) in survivors to 43.3% (95% CI: [27.1-59.6]) in university students, the pooled prevalence of anxiety ranged from 25.0% (95% CI: [12.0-38.0]) in older adults to 43.3% (95% CI: [23.3-63.3]) in pregnant women, and insomnia symptoms ranged from 29.7% (95% CI: [24.4-34.9]) in the general public to 58.4% (95% CI: [28.1-88.6]) in university students. Prevalence of moderate-to-severe mental symptoms was lower but had substantial variation across different populations. The prevalence of mental problems increased over time during the COVID-19 pandemic among the general public, health workers and university students, and decreased among infected patients. Factors associated with increased prevalence for all three mental health symptoms included female sex, and having physical disorders, psychiatric disorders, COVID infection, colleagues or family members infected, experience of frontline work, close contact with infected patients, high exposure risk, quarantine experience and high concern about epidemics. Frequent exercise and good social support were associated with lower risk for these three mental symptoms. In conclusion, mental symptoms are common during epidemics with substantial variation across populations. The population-specific psychological crisis management are needed to decrease the burden of psychological problem and improve the mental wellbeing during epidemic.


Assuntos
COVID-19 , Doenças Transmissíveis , Distúrbios do Início e da Manutenção do Sono , Gravidez , Feminino , Humanos , Idoso , COVID-19/epidemiologia , Pandemias , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Prevalência , Depressão/epidemiologia , Depressão/etiologia , SARS-CoV-2 , Ansiedade/epidemiologia , Ansiedade/etiologia , Fatores de Risco , Doenças Transmissíveis/epidemiologia
18.
Artigo em Inglês | MEDLINE | ID: mdl-36652042

RESUMO

PURPOSE: Activation of mitogen-activated protein kinases (MAPKs) by pathological stimuli participates in cardiovascular diseases. Dysfunction of adventitial fibroblast has emerged as a critical regulator in vascular remodeling, while the potential mechanism remains unclear. In this study, we sought to determine the effect of different activation of MAPKs in adventitial fibroblast contributing to neointima formation. METHODS: Balloon injury procedure was performed in male 12-week-old Sprague-Dawley rats. After injury, MAPK inhibitors were applied to the adventitia of injured arteries to suppress MAPK activation. Adventitial fibroblasts were stimulated by platelet-derived growth factor-BB (PDGF-BB) with or without MAPK inhibitors. RNA sequencing was performed to investigate the change of pathway and cell function. Wound healing, transwell assay, and flow cytometry were used to analyze adventitial fibroblast function. RESULTS: Phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular regulated kinases 1/2 (ERK1/2) was increased in injured arteries after balloon injury. In primary culture of adventitial fibroblasts, PDGF-BB increased phosphorylation of p38, JNK, ERK1/2, and extracellular regulated kinase 5 (ERK5) in a short time, which was normalized by their inhibitors respectively. Compared with the injury group, perivascular administration of four MAPK inhibitors significantly attenuated neointima formation by quantitative analysis of neointimal area, intima to media (I/M) ratio, and lumen area. RNA sequencing of adventitial fibroblasts treated with PDGF-BB with or without four inhibitors demonstrated differentially expressed genes involved in multiple biological processes, including cell adhesion, proliferation, migration, and inflammatory response. Wound healing and transwell assays showed that four inhibitors suppressed PDGF-BB-induced adventitial fibroblast migration. Cell cycle analysis by flow cytometry demonstrated that JNK, ERK1/2, and ERK5 but not p38 inhibitor blocked PDGF-BB-induced G1 phase release associated with decrease expression of cell cycle protein Cyclin D1 and transcription factor GATA4. Moreover, four inhibitors decreased macrophage infiltration into adventitia and monocyte chemoattractant protein-1 (MCP-1) expression. CONCLUSION: These results suggest that MAPKs differentially regulate activation of adventitial fibroblast through GATA4/Cyclin D1 axis that participates in neointima formation.

19.
Nano Lett ; 22(18): 7545-7553, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36083803

RESUMO

Two dimensional Dion-Jacobson (2D DJ) perovskite has emerged as a potential photovoltaic material because of its unique optoelectronic characteristics. However, due to its low structural flexibility and high formation energy, extra assistance is needed during crystallization. Herein, we study the solvent effect on film formation and trap states of 2D DJ perovskite. It is found that the nucleation process of 2D DJ perovskite can be retarded by extra coordination, which is proved by in situ optical spectra. As a benefit, out-of-plane oriented crystallization and ordered phase distribution are realized. Finally, in 1,5-pentanediammonium (PeDA) based 2D DJ perovskite solar cells (PSCs), one of the highest reported open-circuit voltage (VOC) values of 1.25 V with state-of-the-art efficiency of 18.41% is obtained due to greatly shallowed trap states and suppressed nonradiative recombination. The device also exhibits excellent heat tolerance, which maintains 80% of its initial efficiency after being kept under 85 °C after 3000 h.

20.
Rheumatology (Oxford) ; 62(1): 397-406, 2022 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-35412602

RESUMO

OBJECTIVE: To investigate the association between the anti-melanoma differentiation associated gene 5 (MDA5) IgG subclasses and prognosis of patients with dermatomyositis (DM)-associated interstitial lung disease (ILD). METHODS: This retrospective study included 122 anti-MDA5 positive DM-ILD patients admitted from October 2017 to October 2020 as training cohort, and additional 68 patients from August 2014 to September 2017 as validation cohort. The levels of anti-MDA5 total IgG and IgG subclasses were measured using in-house enzyme-linked immunosorbent assays, and analysed in association with the patient prognosis. RESULTS: In the training cohort, the concentrations of anti-MDA5 IgG1 and IgG3 in non-survivors were significantly higher than in survivors (P < 0.05), whereas there were no significant differences in the IgG2 and IgG4 levels. Kaplan-Meier survival analysis revealed that the levels of anti-MDA5 total IgG, IgG1 and IgG3 were associated with mortality (P < 0.05). Multivariate analysis revealed anti-MDA5 IgG1 >13 U/ml and anti-MDA5 IgG3 >11 U/ml were independent risk factors for death of DM-ILD patients (P < 0.05). Anti-MDA5 IgG1 was confirmed as an independent risk factor in the validation cohort, while anti-MDA5 IgG3 was not. Anti-MDA5 IgG1 showed greater discriminable power for patient prognosis (Youden index 0.494) than anti-MDA5 total IgG, IgG3, or the combination of IgG1 and IgG3 (Youden index 0.356, 0.32 and 0.447, respectively). CONCLUSION: Anti-MDA5 IgG1 and IgG3 are significantly associated with poor prognosis in DM-ILD patients, and anti-MDA5 IgG1 is more efficient as a prognostic biomarker in DM-ILD patients.


Assuntos
Dermatomiosite , Doenças Pulmonares Intersticiais , Humanos , Prognóstico , Dermatomiosite/complicações , Estudos Retrospectivos , Helicase IFIH1 Induzida por Interferon , Autoanticorpos , Doenças Pulmonares Intersticiais/complicações
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