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1.
Nature ; 632(8025): 686-694, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39112701

RESUMO

The dopamine transporter has a crucial role in regulation of dopaminergic neurotransmission by uptake of dopamine into neurons and contributes to the abuse potential of psychomotor stimulants1-3. Despite decades of study, the structure, substrate binding, conformational transitions and drug-binding poses of human dopamine transporter remain unknown. Here we report structures of the human dopamine transporter in its apo state, and in complex with the substrate dopamine, the attention deficit hyperactivity disorder drug methylphenidate, and the dopamine-uptake inhibitors GBR12909 and benztropine. The dopamine-bound structure in the occluded state precisely illustrates the binding position of dopamine and associated ions. The structures bound to drugs are captured in outward-facing or inward-facing states, illuminating distinct binding modes and conformational transitions during substrate transport. Unlike the outward-facing state, which is stabilized by cocaine, GBR12909 and benztropine stabilize the dopamine transporter in the inward-facing state, revealing previously unseen drug-binding poses and providing insights into how they counteract the effects of cocaine. This study establishes a framework for understanding the functioning of the human dopamine transporter and developing therapeutic interventions for dopamine transporter-related disorders and cocaine addiction.


Assuntos
Benzotropina , Proteínas da Membrana Plasmática de Transporte de Dopamina , Inibidores da Captação de Dopamina , Dopamina , Humanos , Apoproteínas/metabolismo , Apoproteínas/química , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Benzotropina/metabolismo , Benzotropina/farmacologia , Sítios de Ligação , Cocaína/farmacologia , Cocaína/metabolismo , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Dopamina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Dopamina/antagonistas & inibidores , Proteínas da Membrana Plasmática de Transporte de Dopamina/química , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Inibidores da Captação de Dopamina/metabolismo , Inibidores da Captação de Dopamina/farmacologia , Metilfenidato/metabolismo , Metilfenidato/farmacologia , Modelos Moleculares , Piperazinas/metabolismo , Piperazinas/farmacologia , Ligação Proteica , Conformação Proteica
2.
Nature ; 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37019149

RESUMO

SARS-CoV-2, the causative agent of COVID-19, emerged in December 2019. Its origins remain uncertain. It has been reported that a number of the early human cases had a history of contact with the Huanan Seafood Market. Here we present the results of surveillance for SARS-CoV-2 within the market. From January 1st 2020, after closure of the market, 923 samples were collected from the environment. From 18th January, 457 samples were collected from 18 species of animals, comprising of unsold contents of refrigerators and freezers, swabs from stray animals, and the contents of a fish tank. Using RT-qPCR, SARS-CoV-2 was detected in 73 environmental samples, but none of the animal samples. Three live viruses were successfully isolated. The viruses from the market shared nucleotide identity of 99.99% to 100% with the human isolate HCoV-19/Wuhan/IVDC-HB-01/2019. SARS-CoV-2 lineage A (8782T and 28144C) was found in an environmental sample. RNA-seq analysis of SARS-CoV-2 positive and negative environmental samples showed an abundance of different vertebrate genera at the market. In summary, this study provides information about the distribution and prevalence of SARS-CoV-2 in the Huanan Seafood Market during the early stages of the COVID-19 outbreak.

3.
Proc Natl Acad Sci U S A ; 121(10): e2312150121, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38412127

RESUMO

African swine fever, one of the major viral diseases of swine, poses an imminent threat to the global pig industry. The high-efficient replication of the causative agent African swine fever virus (ASFV) in various organs in pigs greatly contributes to the disease. However, how ASFV manipulates the cell population to drive high-efficient replication of the virus in vivo remains unclear. Here, we found that the spleen reveals the most severe pathological manifestation with the highest viral loads among various organs in pigs during ASFV infection. By using single-cell-RNA-sequencing technology and multiple methods, we determined that macrophages and monocytes are the major cell types infected by ASFV in the spleen, showing high viral-load heterogeneity. A rare subpopulation of immature monocytes represents the major population infected at late infection stage. ASFV causes massive death of macrophages, but shifts its infection into these monocytes which significantly arise after the infection. The apoptosis, interferon response, and antigen-presentation capacity are inhibited in these monocytes which benefits prolonged infection of ASFV in vivo. Until now, the role of immature monocytes as an important target by ASFV has been overlooked due to that they do not express classical monocyte marker CD14. The present study indicates that the shift of viral infection from macrophages to the immature monocytes is critical for maintaining prolonged ASFV infection in vivo. This study sheds light on ASFV tropism, replication, and infection dynamics, and elicited immune response, which may instruct future research on antiviral strategies.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/fisiologia , Baço/patologia , Replicação Viral , Macrófagos/patologia
4.
Nature ; 583(7818): 830-833, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380511

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), which has become a public health emergency of international concern1. Angiotensin-converting enzyme 2 (ACE2) is the cell-entry receptor for severe acute respiratory syndrome coronavirus (SARS-CoV)2. Here we infected transgenic mice that express human ACE2 (hereafter, hACE2 mice) with SARS-CoV-2 and studied the pathogenicity of the virus. We observed weight loss as well as virus replication in the lungs of hACE2 mice infected with SARS-CoV-2. The typical histopathology was interstitial pneumonia with infiltration of considerable numbers of macrophages and lymphocytes into the alveolar interstitium, and the accumulation of macrophages in alveolar cavities. We observed viral antigens in bronchial epithelial cells, macrophages and alveolar epithelia. These phenomena were not found in wild-type mice infected with SARS-CoV-2. Notably, we have confirmed the pathogenicity of SARS-CoV-2 in hACE2 mice. This mouse model of SARS-CoV-2 infection will be valuable for evaluating antiviral therapeutic agents and vaccines, as well as understanding the pathogenesis of COVID-19.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/patologia , Infecções por Coronavirus/virologia , Pulmão/patologia , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/patologia , Pneumonia Viral/virologia , Transgenes , Enzima de Conversão de Angiotensina 2 , Animais , Antígenos Virais/imunologia , Antígenos Virais/metabolismo , Betacoronavirus/imunologia , Betacoronavirus/metabolismo , Brônquios/patologia , Brônquios/virologia , COVID-19 , Infecções por Coronavirus/imunologia , Modelos Animais de Doenças , Células Epiteliais/patologia , Células Epiteliais/virologia , Feminino , Humanos , Imunoglobulina G/imunologia , Pulmão/imunologia , Pulmão/virologia , Linfócitos/imunologia , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/virologia , Masculino , Camundongos , Camundongos Transgênicos , Pandemias , Pneumonia Viral/imunologia , Receptores de Complemento 3d/genética , Receptores de Complemento 3d/metabolismo , SARS-CoV-2 , Replicação Viral , Redução de Peso
5.
Proc Natl Acad Sci U S A ; 120(48): e2309506120, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37983498

RESUMO

African swine fever virus (ASFV), a devastating pathogen to the worldwide swine industry, mainly targets macrophage/monocyte lineage, but how the virus enters host cells has remained unclear. Here, we report that ASFV utilizes apoptotic bodies (ApoBDs) for infection and cell-cell transmission. We show that ASFV induces cell apoptosis of primary porcine alveolar macrophages (PAMs) at the late stage of infection to productively shed ApoBDs that are subsequently swallowed by neighboring PAMs to initiate a secondary infection as evidenced by electron microscopy and live-cell imaging. Interestingly, the virions loaded within ApoBDs are exclusively single-enveloped particles that are devoid of the outer layer of membrane and represent a predominant form produced during late infection. The in vitro purified ApoBD vesicles are capable of mediating virus infection of naive PAMs, but the transmission can be significantly inhibited by blocking the "eat-me" signal phosphatidyserine on the surface of ApoBDs via Annexin V or the efferocytosis receptor TIM4 on the recipient PAMs via anti-TIM4 antibody, whereas overexpression of TIM4 enhances virus infection. The same treatment however did not affect the infection by intracellular viruses. Importantly, the swine sera to ASFV exert no effect on the ApoBD-mediated transmission but can partially act on the virions lacking the outer layer of membrane. Thus, ASFV has evolved to hijack a normal cellular pathway for cell-cell spread to evade host responses.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Vesículas Extracelulares , Suínos , Animais , Vírus da Febre Suína Africana/fisiologia , Macrófagos/metabolismo , Monócitos/metabolismo , Vesículas Extracelulares/metabolismo
6.
J Virol ; 98(9): e0113224, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39194294

RESUMO

The 5' untranslated region (5'UTR) of many positive-stranded RNA viruses contain functional regulatory sequences. Here, we show that the porcine reproductive and respiratory syndrome virus (PRRSV), a member of arteriviruses, harbors small upstream open reading frames (uORFs) in its 5'UTR. Bioinformatics analysis shows that this feature is relatively well conserved among PRRSV strains and Arteriviridae. We also identified a uORF, namely uORF2, in the PRRSV strain JXwn06, that possesses translational activity and exerts a suppressive effect on the expression of the primary ORF evidenced by in vitro reporter assays. We tested its importance via reverse genetics by introducing a point mutation into the PRRSV infectious cDNA clone to inactivate the start codon of uORF2. The recovered mutant virus Mut2 surprisingly replicated to the same level as the wild-type virus (WT), but induced a higher level of inflammatory cytokines (e.g., TNF-α, IL-1ß, and IL-6) both in vitro and in animal experiments, correlating well with more severe lung injury and higher death rate. In line with this, over-expression of uORF2 in transfected cells significantly inhibited poly(I:C)-induced expression of inflammatory cytokines. Together, our data support the idea that uORF2 encodes a novel, functional regulator of PRRSV virulence despite of its short size. IMPORTANCE: PRRSV has remained a major challenge to the world swine industry, but we still do not know much about its biology and pathogenesis. Here, we provide evidence to show that the 5'UTR of PRRSV strain JXwn06 harbors a functional uORF that has the coding capacity and regulates induction of inflammation as demonstrated by in vitro assays and animal experiment. The findings reveal a novel viral factor that regulates cellular inflammation and provide insight into the understanding of PRRSV pathogenesis.


Assuntos
Regiões 5' não Traduzidas , Fases de Leitura Aberta , Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Animais , Regiões 5' não Traduzidas/genética , Suínos , Síndrome Respiratória e Reprodutiva Suína/virologia , Replicação Viral , Inflamação/virologia , Linhagem Celular , Citocinas/metabolismo , Citocinas/genética
7.
Cell Mol Life Sci ; 81(1): 240, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806818

RESUMO

The pulmonary endothelium is a dynamic and metabolically active monolayer of endothelial cells. Dysfunction of the pulmonary endothelial barrier plays a crucial role in the acute lung injury (ALI) and acute respiratory distress syndrome (ARDS), frequently observed in the context of viral pneumonia. Dysregulation of tight junction proteins can lead to the disruption of the endothelial barrier and subsequent leakage. Here, the highly pathogenic porcine reproductive and respiratory syndrome virus (HP-PRRSV) served as an ideal model for studying ALI and ARDS. The alveolar lavage fluid of pigs infected with HP-PRRSV, and the supernatant of HP-PRRSV infected pulmonary alveolar macrophages were respectively collected to treat the pulmonary microvascular endothelial cells (PMVECs) in Transwell culture system to explore the mechanism of pulmonary microvascular endothelial barrier leakage caused by viral infection. Cytokine screening, addition and blocking experiments revealed that proinflammatory cytokines IL-1ß and TNF-α, secreted by HP-PRRSV-infected macrophages, disrupt the pulmonary microvascular endothelial barrier by downregulating claudin-8 and upregulating claudin-4 synergistically. Additionally, three transcription factors interleukin enhancer binding factor 2 (ILF2), general transcription factor III C subunit 2 (GTF3C2), and thyroid hormone receptor-associated protein 3 (THRAP3), were identified to accumulate in the nucleus of PMVECs, regulating the transcription of claudin-8 and claudin-4. Meanwhile, the upregulation of ssc-miR-185 was found to suppress claudin-8 expression via post-transcriptional inhibition. This study not only reveals the molecular mechanisms by which HP-PRRSV infection causes endothelial barrier leakage in acute lung injury, but also provides novel insights into the function and regulation of tight junctions in vascular homeostasis.


Assuntos
Claudinas , Células Endoteliais , Pulmão , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , Suínos , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Pulmão/metabolismo , Pulmão/virologia , Pulmão/patologia , Pulmão/irrigação sanguínea , Células Endoteliais/metabolismo , Células Endoteliais/virologia , Claudinas/metabolismo , Claudinas/genética , Síndrome Respiratória e Reprodutiva Suína/metabolismo , Síndrome Respiratória e Reprodutiva Suína/virologia , Síndrome Respiratória e Reprodutiva Suína/patologia , Claudina-4/metabolismo , Claudina-4/genética , Macrófagos Alveolares/metabolismo , Macrófagos Alveolares/virologia , Endotélio Vascular/metabolismo , Endotélio Vascular/virologia , Endotélio Vascular/patologia , Células Cultivadas , Permeabilidade Capilar , Lesão Pulmonar Aguda/metabolismo , Lesão Pulmonar Aguda/virologia , Lesão Pulmonar Aguda/patologia , Citocinas/metabolismo
8.
Cell Mol Life Sci ; 81(1): 221, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38763964

RESUMO

In females, the pathophysiological mechanism of poor ovarian response (POR) is not fully understood. Considering the expression level of p62 was significantly reduced in the granulosa cells (GCs) of POR patients, this study focused on identifying the role of the selective autophagy receptor p62 in conducting the effect of follicle-stimulating hormone (FSH) on antral follicles (AFs) formation in female mice. The results showed that p62 in GCs was FSH responsive and that its level increased to a peak and then decreased time-dependently either in ovaries or in GCs after gonadotropin induction in vivo. GC-specific deletion of p62 resulted in subfertility, a significantly reduced number of AFs and irregular estrous cycles, which were same as pathophysiological symptom of POR. By conducting mass spectrum analysis, we found the ubiquitination of proteins was decreased, and autophagic flux was blocked in GCs. Specifically, the level of nonubiquitinated Wilms tumor 1 homolog (WT1), a transcription factor and negative controller of GC differentiation, increased steadily. Co-IP results showed that p62 deletion increased the level of ubiquitin-specific peptidase 5 (USP5), which blocked the ubiquitination of WT1. Furthermore, a joint analysis of RNA-seq and the spatial transcriptome sequencing data showed the expression of steroid metabolic genes and FSH receptors pivotal for GCs differentiation decreased unanimously. Accordingly, the accumulation of WT1 in GCs deficient of p62 decreased steroid hormone levels and reduced FSH responsiveness, while the availability of p62 in GCs simultaneously ensured the degradation of WT1 through the ubiquitin‒proteasome system and autophagolysosomal system. Therefore, p62 in GCs participates in GC differentiation and AF formation in FSH induction by dynamically controlling the degradation of WT1. The findings of the study contributes to further study the pathology of POR.


Assuntos
Hormônio Foliculoestimulante , Células da Granulosa , Folículo Ovariano , Proteína Sequestossoma-1 , Ubiquitinação , Proteínas WT1 , Animais , Hormônio Foliculoestimulante/metabolismo , Hormônio Foliculoestimulante/farmacologia , Feminino , Proteínas WT1/metabolismo , Proteínas WT1/genética , Camundongos , Folículo Ovariano/metabolismo , Folículo Ovariano/efeitos dos fármacos , Células da Granulosa/metabolismo , Células da Granulosa/efeitos dos fármacos , Proteína Sequestossoma-1/metabolismo , Proteína Sequestossoma-1/genética , Camundongos Endogâmicos C57BL , Autofagia/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Humanos , Camundongos Knockout
9.
Proc Natl Acad Sci U S A ; 119(29): e2201169119, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858300

RESUMO

Protein kinase R (PKR) is a critical host restriction factor against invading viral pathogens. However, this molecule is inactivated in the cells infected with porcine reproductive and respiratory syndrome virus (PRRSV), an economically devastating pathogen to the world swine industry. Here, we report that this event is to suppress cellular inflammation and is mediated by the viral replicase protein nsp1ß. We show that nsp1ß is a stress-responsive protein, enters virus-induced stress granules (SGs) during infection, and repurposes SGs into a proviral platform, where it co-opts the SG core component G3BP1 to interact with PKR in a regulated manner. RNA interference silencing of G3BP1 or mutation of specific nsp1ß residues (VS19GG) can abolish the antagonization of PKR activation. The viral mutant carrying the corresponding mutations induces elevated level of PKR phosphorylation and pronounced production of inflammatory cytokines (e.g., tumor necrosis factor-α, interleukin [IL]-6, and IL-8), whereas small-interfering RNA knockdown of PKR or treatment with C16, a PKR inhibitor, blocks this effect. Thus, PRRSV has evolved a unique strategy to evade PKR restriction to suppress host inflammatory responses.


Assuntos
Fatores de Restrição Antivirais , DNA Helicases , Evasão da Resposta Imune , Proteínas de Ligação a Poli-ADP-Ribose , Vírus da Síndrome Respiratória e Reprodutiva Suína , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA , Grânulos de Estresse , Proteínas não Estruturais Virais , eIF-2 Quinase , Animais , Fatores de Restrição Antivirais/metabolismo , DNA Helicases/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Grânulos de Estresse/virologia , Suínos , Proteínas não Estruturais Virais/metabolismo , Replicação Viral , eIF-2 Quinase/metabolismo
10.
J Am Chem Soc ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39283164

RESUMO

We report a mild method for the copper-catalyzed amination of aryl chlorides. Key to the success of the method was the use of highly sterically encumbered N1,N2-diaryl diamine ligands which resist catalyst deactivation, allowing reactions to proceed at significantly lower temperatures and with a broader scope than current protocols. A sequence of highly chemoselective C-N and C-O cross-coupling reactions were demonstrated, and mechanistic studies indicate that oxidative addition of the Cu catalyst to the aryl chlorides is rate-limiting. We anticipate that the design principles disclosed herein will help motivate further advances in Cu-catalyzed transformations of aryl chlorides.

11.
Eur J Neurosci ; 60(1): 3677-3693, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38711280

RESUMO

Gastrodin, an anti-inflammatory herbal agent, is known to suppress microglia activation. Here, we investigated whether it would exert a similar effect in reactive astrocytes and whether it might act through the renin-angiotensin system (RAS) and sirtuin 3 (SIRT3). Angiotensinogen (ATO), angiotensin-converting enzyme (ACE), angiotensin II type 1 (AT1) and type 2 (AT2) receptor and SIRT3 expression was detected in TNC-1 astrocytes treated with BV-2 microglia conditioned medium (CM) with or without gastrodin and lipopolysaccharide (LPS) pre-treatment by RT-PCR, immunofluorescence and western blotting analysis. Expression of C3 (A1 astrocyte marker), S100A10 (A2 astrocyte marker), proinflammatory cytokines and neurotrophic factors was then evaluated. The results showed a significant increase of ATO, ACE, AT1, SIRT3, C3, proinflammatory cytokines and neurotrophic factors expression in TNC-1 astrocytes incubated in CM + LPS when compared with cells incubated in the CM, but AT2 and S100A10 expression was reduced. TNC-1 astrocytes responded vigorously to BV-2 CM treated with gastrodin + LPS as compared with the control. This was evident by the decreased expression of the abovementioned protein markers, except for AT2 and S100A10. Interestingly, SIRT3, IGF-1 and BDNF expression was enhanced, suggesting that gastrodin inhibited the expression of RAS and proinflammatory mediators but promoted the expression of neurotrophic factors. And gastrodin regulated the phenotypic changes of astrocytes through AT1. Additionally, azilsartan (a specific inhibitor of AT1) inhibited the expression of C3 and S100A10, which remained unaffected in gastrodin and azilsartan combination treatment. These findings provide evidence that gastrodin may have a therapeutic effect via regulating RAS-SIRT3.


Assuntos
Astrócitos , Álcoois Benzílicos , Glucosídeos , Microglia , Sistema Renina-Angiotensina , Sirtuína 3 , Glucosídeos/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Animais , Álcoois Benzílicos/farmacologia , Camundongos , Sirtuína 3/metabolismo , Sistema Renina-Angiotensina/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Mediadores da Inflamação/metabolismo , Citocinas/metabolismo , Linhagem Celular
12.
Anal Chem ; 96(29): 11809-11822, 2024 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-38975729

RESUMO

Plant samples with irregular morphology are challenging for longitudinal tissue sectioning. This has restricted the ability to gain insight into some plants using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI). Herein, we develop a novel technique termed electromagnetic field-assisted frozen tissue planarization (EMFAFTP). This technique involves using a pair of adjustable electromagnets on both sides of a plant tissue. Under an optimized electromagnetic field strength, nondestructive planarization and regularization of the frozen tissue is induced, allowing the longitudinal tissue sectioning that favors subsequent molecular profiling by MALDI-MSI. As a proof of concept, flowers, leaves and roots with irregular morphology from six plant species are chosen to evaluate the performance of EMFAFTP for MALDI-MSI of secondary metabolites, amino acids, lipids, and proteins among others in the plant samples. The significantly enhanced MALDI-MSI capabilities of these endogenous molecules demonstrate the robustness of EMFAFTP and suggest it has the potential to become a standard technique for advancing MALDI-MSI into a new era of plant spatial omics.


Assuntos
Campos Eletromagnéticos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Folhas de Planta/metabolismo , Folhas de Planta/química , Congelamento , Raízes de Plantas/metabolismo , Raízes de Plantas/química , Plantas/metabolismo , Plantas/química , Flores/metabolismo , Flores/química
13.
Biochem Biophys Res Commun ; 734: 150639, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39241621

RESUMO

The target of rapamycin (TOR) protein, renowned for its highly conserved nature across species, plays a pivotal role in modulating signaling pathways via its multiprotein complexes, TORC1 and TORC2. The relationship between TOR and its inhibitor, rapamycin, especially in the context of lifespan extension, has earned significant attention. Unlike mammals, which have a single TOR gene, the budding yeast Saccharomyces cerevisiae features two TOR paralogs: TOR1 and TOR2. Non-essential TOR1 gene has been the focus of extensive research, whereas the essential TOR2 gene has received relatively little attention in lifespan studies. In our research, we engineered a point mutation (Ser-1975-Ile) within the FKBP12-rapamycin-binding (FRB) domain of Tor2p to block rapamycin binding. Remarkably, this mutation negated the lifespan-extending benefits of rapamycin, irrespective of the TOR1 gene status. Our findings indicate that the TOR2 gene likely serves as the primary mammalian ortholog, playing a crucial role in mediating the effects of rapamycin on lifespan extension. This discovery opens a new avenue for the development of innovative anti-aging agents targeting the TOR. complex.

14.
Small ; 20(10): e2304814, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37875646

RESUMO

Owing to the limited electrochemical stability window of carbonate electrolytes, the initial formation of a solid electrolyte interphase and surface film on the negative and positive electrode surfaces by the decomposition of the electrolyte component is inevitable for the operation of lithium secondary batteries. The deposited film on the surface of the active material is vital for reducing further electrochemical side reactions at the surface; hence, the manipulation of this formation process is necessary for the appropriate operation of the assembled battery system. In this study, the thermal decomposition of LiPF6 salt is used as a surface passivation agent, which is autocatalytically formed during high-temperature storage. The thermally formed difluorophosphoric acid is subsequently oxidized on the partially charged high-Ni positive electrode surface, which improves the cycleability of lithium metal cells via phosphorus- and fluorine-based surface film formation. Moreover, the improvement in the high-temperature cycleability is demonstrated by controlling the formation process in the lithium-ion pouch cell with a short period of high-temperature storage before battery usage.

15.
J Virol ; 97(3): e0168922, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36916907

RESUMO

Fast evolution in the field of the replicase nsp2 represents a most prominent feature of porcine reproductive and respiratory syndrome virus (PRRSV). Here, we determined its biological significance in viral pathogenesis by constructing interlineage chimeric mutants between the Chinese highly pathogenic PRRSV (HP-PRRSV) strain JXwn06 (lineage 8) and the low-virulent NADC30-like strain CHsx1401 (lineage 1). Replacement with nsp2 from JXwn06 was surprisingly lethal to the backbone virus CHsx1401, but combined substitution with the structural protein-coding region (SP) gave rise to viable virus CHsx1401-SPnsp2JX. Meanwhile, a derivative carrying only the SP region (CHsx1401-SPJX) served as a control. Subsequent animal experiments revealed that acquisition of SP alone (CHsx1401-SPJX) did not allow CHsx1401 to gain much virulence, but additional swapping of HP-PRRSV nsp2 (CHsx1401-SPnsp2JX) enabled CHsx1401 to acquire some properties of HP-PRRSV, exemplified by prolonged high fever, microscopic lung hemorrhage, and a significant increase in proinflammatory cytokines in the acute stage. Consistent with this was the transcriptomic analysis of persistently infected secondary lymphoid tissues that revealed a much stronger induction of host cellular immune responses in this group and identified several core immune genes (e.g., TLR4, IL-1ß, MPO, etc.) regulated by HP-PRRSV nsp2. Interestingly, immune activation status in the individual groups correlated well with the rate of viremia clearance and viral tissue load reduction. Overall, the above results suggest that the Chinese HP-PRRSV nsp2 is a critical virulence regulator and highlight the importance of nsp2 genetic variation in modulating PRRSV virulence and persistence via immune modulation. IMPORTANCE Porcine reproductive and respiratory syndrome virus (PRRSV) has been a major threat to the world swine industry. In the field, rapid genetic variations (e.g., deletion, mutation, recombination, etc.) within the nsp2 region present an intriguing conundrum to PRRSV biology and pathogenesis. By making chimeric mutants, here, we show that the Chinese highly pathogenic PRRSV (HP-PRRSV) nsp2 is a virulence factor and a much stronger inducer of host immune responses (e.g., inflammation) than its counterpart, currently epidemic, NADC30-like strains. Differences in the ability to modulate host immunity provide insight into the mechanisms of why NADC30-like strains and their derivatives are rising to be the dominant viruses, whereas the Chinese HP-PRRSV strains gradually give away center stage in the field. Our results have important implications in understanding PRRSV evolution, interlineage recombination, and persistence.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Animais , China/epidemiologia , Citocinas , Variação Genética , Genoma Viral , Filogenia , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Suínos , Virulência/genética
16.
Mod Pathol ; 37(1): 100384, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37972928

RESUMO

Tumor-agnostic testing for NTRK1-3 gene rearrangements is required to identify patients who may benefit from TRK inhibitor therapies. The overarching objective of this study was to establish a high-quality pan-TRK immunohistochemistry (IHC) screening assay among 18 large regional pathology laboratories across Canada using pan-TRK monoclonal antibody clone EPR17341 in a ring study design. TRK-fusion positive and negative tumor samples were collected from participating sites, with fusion status confirmed by panel next-generation sequencing assays. Each laboratory received: (1) unstained sections from 30 cases of TRK-fusion-positive or -negative tumors, (2) 2 types of reference standards: TRK calibrator slides and IHC critical assay performance controls (iCAPCs), (3) EPR17341 antibody, and (4) suggestions for developing IHC protocols. Participants were asked to optimize the IHC protocol for their instruments and detection systems by using iCAPCs, to stain the 30 study cases, and to report the percentage scores for membranous, cytoplasmic, and nuclear staining. TRK calibrators were used to assess the analytical sensitivity of IHC protocols developed by using the 2 reference standards. Fifteen of 18 laboratories achieved diagnostic sensitivity of 100% against next-generation sequencing. The diagnostic specificity ranged from 40% to 90%. The results did not differ significantly between positive scores based on the presence of any type of staining vs the presence of overall staining in ≥1% of cells. The median limit of detection measured by TRK calibrators was 76,000 molecules/cell (range 38,000 to >200,000 molecules/cell). Three different patterns of staining were observed in 19 TRK-positive cases, cytoplasmic-only in 7 samples, nuclear and cytoplasmic in 9 samples, and cytoplasmic and membranous in 3 samples. The Canadian multicentric pan-TRK study illustrates a successful strategy to accelerate the multicenter harmonization and implementation of pan-TRK immunohistochemical screening that achieves high diagnostic sensitivity by using laboratory-developed tests where laboratories used centrally developed reference materials. The measurement of analytical sensitivity by using TRK calibrators provided additional insights into IHC protocol performance.


Assuntos
Neoplasias , Humanos , Imuno-Histoquímica , Canadá , Anticorpos Monoclonais , Receptor trkA/genética , Proteínas de Fusão Oncogênica/genética , Biomarcadores Tumorais/genética
17.
Microb Pathog ; 195: 106885, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39182857

RESUMO

Porcine epidemic diarrhea virus (PEDV), porcine deltacoronavirus (PDCoV) and transmissible gastroenteritis virus (TGEV) are three clinically common coronaviruses causing diarrhea in pigs, with indistinguishable clinical signs and pathological changes. Rapid, portable and reliable differential diagnosis of these three pathogens is crucial for the prompt implementation of appropriate control measures. In this study, we developed a triplex nucleic acid assay that combines reverse transcription recombinase-aided amplification (RT-RAA) with lateral flow assay (LFA) by targeting the most conserved genomic region in the ORF1b genes of PEDV, PDCoV and TGEV. The entire detection process of the triplex RT-RAA-LFA assay included 10-min nucleic acid amplification at 42 °C and 5-min visual LFA readout at room temperature. The assay could specifically differentiate PEDV, PDCoV and TGEV without cross-reaction with any other major swine pathogens. Sensitivity analysis showed that the triplex RT-RAA-LFA assay was able to detect the viral RNA extracted from the spiked fecal samples with the minimum of 1 × 100 TCID50 PEDV, 1 × 104 TCID50 PDCoV, and 1 × 102 TCID50 TGEV per reaction, respectively. Further analysis showed that the 95 % detection limit (LOD) of triplex RT-RAA-LFA for PEDV, PDCoV, and TGEV were 22, 478, and 205 copies of recombinant plasmids per reaction, respectively. The diagnostic performance of triplex RT-RAA-LFA was compared with that of PEDV, PDCoV and TGEV respective commercial real-time RT-PCR kits by testing 114 clinical rectal swab samples in parallel. The total diagnostic coincidence rates of triplex RT-RAA-LFA with real-time RT-PCR kits of PEDV, PDCoV and TGEV were 100 %, 99.1 % and 99.1 %, respectively, and their Kappa values were 1.00, 0.958 and 0.936, respectively. Collectively, the RT-RAA-LFA assay is a powerful tool for the rapid, portable, visual, and synchronous differential diagnosis of PEDV, PDCoV, and TGEV.


Assuntos
Infecções por Coronavirus , Deltacoronavirus , Fezes , Técnicas de Amplificação de Ácido Nucleico , Vírus da Diarreia Epidêmica Suína , RNA Viral , Sensibilidade e Especificidade , Doenças dos Suínos , Vírus da Gastroenterite Transmissível , Animais , Suínos , Vírus da Gastroenterite Transmissível/isolamento & purificação , Vírus da Gastroenterite Transmissível/genética , Vírus da Diarreia Epidêmica Suína/isolamento & purificação , Vírus da Diarreia Epidêmica Suína/genética , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/virologia , RNA Viral/genética , RNA Viral/isolamento & purificação , Fezes/virologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/veterinária , Infecções por Coronavirus/virologia , Diagnóstico Diferencial , Deltacoronavirus/isolamento & purificação , Deltacoronavirus/genética , Técnicas de Amplificação de Ácido Nucleico/métodos , Técnicas de Amplificação de Ácido Nucleico/veterinária , Gastroenterite Suína Transmissível/diagnóstico , Gastroenterite Suína Transmissível/virologia , Técnicas de Diagnóstico Molecular/métodos , Diarreia/virologia , Diarreia/veterinária , Diarreia/diagnóstico
18.
Opt Lett ; 49(16): 4642-4645, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39146124

RESUMO

This paper presents the first-principles design approach for x-ray active optics. The feature of deterministic modulation enables the simulation-modulation cycle in place of the measurement-modulation feedback loops used in traditional active optics. We apply an x-ray mirror with localized thermal elastic deformation to validate the idea. Our experiments have demonstrated that the new active optics have the potential to outperform the accuracy of surface shape metrology instruments.

19.
Chemistry ; : e202402667, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39109456

RESUMO

A novel room-temperature liquid crystal of tetraphenylethylene derivative (TPE-DHAB) was synthesized using an ionic self-assembly strategy. The TPE-DHAB complex exhibits typical aggregation-induced emission properties and a unique helical supramolecular structure. Moreover, the generation and handedness inversion of circularly polarized luminescence (CPL) can be achieved through further chiral solvation, providing a facile approach to fabricate room-temperature liquid crystalline materials with controllable supramolecular structures and tunable CPL properties through a synergistic strategy of ionic self-assembly and chiral solvation process.

20.
J Magn Reson Imaging ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38205712

RESUMO

BACKGROUND: Accurate evaluation of the axillary lymph node (ALN) status is needed for determining the treatment protocol for breast cancer (BC). The value of magnetic resonance imaging (MRI)-based tumor heterogeneity in assessing ALN metastasis in BC is unclear. PURPOSE: To assess the value of deep learning (DL)-derived kinetic heterogeneity parameters based on BC dynamic contrast-enhanced (DCE)-MRI to infer the ALN status. STUDY TYPE: Retrospective. SUBJECTS: 1256/539/153/115 patients in the training cohort, internal validation cohort, and external validation cohorts I and II, respectively. FIELD STRENGTH/SEQUENCE: 1.5 T/3.0 T, non-contrast T1-weighted spin-echo sequence imaging (T1WI), DCE-T1WI, and diffusion-weighted imaging. ASSESSMENT: Clinical pathological and MRI semantic features were obtained by reviewing histopathology and MRI reports. The segmentation of the tumor lesion on the first phase of T1WI DCE-MRI images was applied to other phases after registration. A DL architecture termed convolutional recurrent neural network (ConvRNN) was developed to generate the KHimage (kinetic heterogeneity of DCE-MRI image) score that indicated the ALN status in patients with BC. The model was trained and optimized on training and internal validation cohorts, tested on two external validation cohorts. We compared ConvRNN model with other 10 models and the subgroup analyses of tumor size, magnetic field strength, and molecular subtype were also evaluated. STATISTICAL TESTS: Chi-squared, Fisher's exact, Student's t, Mann-Whitney U tests, and receiver operating characteristics (ROC) analysis were performed. P < 0.05 was considered significant. RESULTS: The ConvRNN model achieved area under the curve (AUC) of 0.802 in the internal validation cohort and 0.785-0.806 in the external validation cohorts. The ConvRNN model could well evaluate the ALN status of the four molecular subtypes (AUC = 0.685-0.868). The patients with larger tumor sizes (>5 cm) were more susceptible to ALN metastasis with KHimage scores of 0.527-0.827. DATA CONCLUSION: A ConvRNN model outperformed traditional models for determining the ALN status in patients with BC. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

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