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1.
Mol Cell ; 83(23): 4304-4317.e8, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37949069

RESUMO

RNA-binding proteins (RBPs) control messenger RNA fate in neurons. Here, we report a mechanism that the stimuli-induced neuronal translation is mediated by phosphorylation of a YTHDF1-binding protein FMRP. Mechanistically, YTHDF1 can condense with ribosomal proteins to promote the translation of its mRNA targets. FMRP regulates this process by sequestering YTHDF1 away from the ribosome; upon neuronal stimulation, FMRP becomes phosphorylated and releases YTHDF1 for translation upregulation. We show that a new small molecule inhibitor of YTHDF1 can reverse fragile X syndrome (FXS) developmental defects associated with FMRP deficiency in an organoid model. Our study thus reveals that FMRP and its phosphorylation are important regulators of activity-dependent translation during neuronal development and stimulation and identifies YTHDF1 as a potential therapeutic target for FXS in which developmental defects caused by FMRP depletion could be reversed through YTHDF1 inhibition.


Assuntos
Proteína do X Frágil da Deficiência Intelectual , Síndrome do Cromossomo X Frágil , Humanos , Fosforilação , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Neurônios/metabolismo , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/metabolismo , Proteínas Ribossômicas/metabolismo , RNA Mensageiro/genética , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(41): e2311416120, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37782781

RESUMO

An evolutionarily conserved region of the TDP-43 low-complexity domain (LCD) twenty residues in length can adopt either an α-helical or ß-strand conformation. When in the latter conformation, TDP-43 self-associates via the formation of a labile, cross-ß structure. Self-association can be monitored via the formation of phase-separated protein droplets. Exposure of droplets to hydrogen peroxide leads to oxidation of conserved methionine residues distributed throughout the LCD. Oxidation disassembles the cross-ß structure, thus eliminating both self-association and phase separation. Here, we demonstrate that this process reciprocally enables formation of α-helical structure in precisely the same region formerly functioning to facilitate ß-strand-mediated self-association. We further observe that the α-helical conformation allows interaction with a lipid-like detergent and that exposure to lipids enhances the ß-to-α conformational switch. We hypothesize that regulation of this oxidative switch will prove to be important to the control of localized translation within vertebrate cells. The experimental observations reported herein were heavily reliant on studies of 1,6-hexanediol, a chemical agent that selectively dissolves labile structures formed via the self-association of protein domains of low sequence complexity. This aliphatic alcohol is shown to exert its dissociative activity primarily via hydrogen-bonding interactions with carbonyl oxygen atoms of the polypeptide backbone. Such observations underscore the central importance of backbone-mediated protein:protein interactions that facilitate the self-association and phase separation of LCDs.


Assuntos
Proteínas de Ligação a DNA , Peptídeos , Proteínas de Ligação a DNA/metabolismo , Peptídeos/química , Domínios Proteicos , Metionina/metabolismo , Estresse Oxidativo
3.
Proc Natl Acad Sci U S A ; 120(33): e2302799120, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37549264

RESUMO

Members of the nucleobase/ascorbic acid transporter (NAT) gene family are found in all kingdoms of life. In mammals, the concentrative uptake of ascorbic acid (vitamin C) by members of the NAT family is driven by the Na+ gradient, while the uptake of nucleobases in bacteria is powered by the H+ gradient. Here, we report the structure and function of PurTCp, a NAT family member from Colwellia psychrerythraea. The structure of PurTCp was determined to 2.80 Å resolution by X-ray crystallography. PurTCp forms a homodimer, and each protomer has 14 transmembrane segments folded into a transport domain (core domain) and a scaffold domain (gate domain). A purine base is present in the structure and defines the location of the substrate binding site. Functional studies reveal that PurTCp transports purines but not pyrimidines and that purine binding and transport is dependent on the pH. Mutation of a conserved aspartate residue close to the substrate binding site reveals the critical role of this residue in H+-dependent transport of purines. Comparison of the PurTCp structure with transporters of the same structural fold suggests that rigid-body motions of the substrate-binding domain are central for substrate translocation across the membrane.


Assuntos
Ácido Ascórbico , Purinas , Animais , Transporte Biológico , Purinas/metabolismo , Mutação , Sítios de Ligação , Ácido Ascórbico/metabolismo , Mamíferos/metabolismo
4.
Cereb Cortex ; 34(2)2024 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-38367612

RESUMO

Consequences of perceptual training, such as improvements in discriminative ability, are highly stimulus and task specific. Therefore, most studies on auditory training-induced plasticity in adult brain have focused on the sensory aspects, particularly on functional and structural effects in the auditory cortex. Auditory training often involves, other than auditory demands, significant cognitive components. Yet, how auditory training affects cognition-related brain regions, such as the hippocampus, remains unclear. Here, we found in female rats that auditory cue-based go/no-go training significantly improved the memory-guided behaviors associated with hippocampus. The long-term potentiations of the trained rats recorded in vivo in the hippocampus were also enhanced compared with the naïve rats. In parallel, the phosphorylation level of calcium/calmodulin-dependent protein kinase II and the expression of parvalbumin-positive interneurons in the hippocampus were both upregulated. These findings demonstrate that auditory training substantially remodels the processing and function of brain regions beyond the auditory system, which are associated with task demands.


Assuntos
Córtex Auditivo , Hipocampo , Ratos , Feminino , Animais , Hipocampo/fisiologia , Encéfalo , Potenciação de Longa Duração , Córtex Auditivo/fisiologia
5.
Proc Natl Acad Sci U S A ; 119(26): e2202034119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35727982

RESUMO

CRISPR diagnostics based on nucleic acid amplification faces barriers to its commercial use, such as contamination risks and insufficient sensitivity. Here, we propose a robust solution involving optochemical control of CRISPR RNA (crRNA) activation in CRISPR detection. Based on this strategy, recombinase polymerase amplification (RPA) and CRISPR-Cas12a detection systems can be integrated into a completely closed test tube. crRNA can be designed to be temporarily inactivated so that RPA is not affected by Cas12a cleavage. After the RPA reaction is completed, the CRISPR-Cas12a detection system is activated under rapid light irradiation. This photocontrolled, fully closed CRISPR diagnostic system avoids contamination risks and exhibits a more than two orders of magnitude improvement in sensitivity compared with the conventional one-pot assay. This photocontrolled CRISPR method was applied to the clinical detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA, achieving detection sensitivity and specificity comparable to those of PCR. Furthermore, a compact and automatic photocontrolled CRISPR detection device was constructed.


Assuntos
Proteínas de Bactérias , Proteínas Associadas a CRISPR , Sistemas CRISPR-Cas , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Endodesoxirribonucleases , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , COVID-19/diagnóstico , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas/efeitos da radiação , Humanos , RNA/efeitos da radiação , Recombinases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2/isolamento & purificação , Sensibilidade e Especificidade
6.
J Neurosci ; 43(16): 2850-2859, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-36948582

RESUMO

Antidepressants, while effective in treating depression and anxiety disorders, also induce deficits in sensory (particularly auditory) processing, which in turn may exacerbate psychiatric symptoms. How antidepressants cause auditory signature deficits remains largely unknown. Here, we found that fluoxetine-treated adult female rats were significantly less accurate when performing a tone-frequency discrimination task compared with age-matched control rats. Their cortical neurons also responded less selectively to sound frequencies. The degraded behavioral and cortical processing was accompanied by decreased cortical perineuronal nets, particularly those wrapped around parvalbumin-expressing inhibitory interneurons. Furthermore, fluoxetine induced critical period-like plasticity in their already mature auditory cortices; therefore, a brief rearing of these drug-treated rats under an enriched acoustic environment renormalized auditory processing degraded by fluoxetine. The altered cortical expression of perineuronal nets was also reversed as a result of enriched sound exposure. These findings suggest that the adverse effects of antidepressants on auditory processing, possibly because of a reduction in intracortical inhibition, can be substantially alleviated by simply pairing drug treatment with passive, enriched sound exposure. They have important implications for understanding the neurobiological basis of antidepressant effects on hearing and for designing novel pharmacological treatment strategies for psychiatric disorders.SIGNIFICANCE STATEMENT Clinical experience suggests that antidepressants adversely affect sensory (particularly auditory) processing, which can exacerbate patients' psychiatric symptoms. Here, we show that the antidepressant fluoxetine reduces cortical inhibition in adult rats, leading to degraded behavioral and cortical spectral processing of sound. Importantly, fluoxetine induces a critical period-like state of plasticity in the mature cortex; therefore, a brief rearing under an enriched acoustic environment is sufficient to reverse the changes in auditory processing caused by the administration of fluoxetine. These results provide a putative neurobiological basis for the effects of antidepressants on hearing and indicate that antidepressant treatment combined with enriched sensory experiences could optimize clinical outcomes.


Assuntos
Córtex Auditivo , Fluoxetina , Ratos , Feminino , Animais , Fluoxetina/farmacologia , Percepção Auditiva/fisiologia , Som , Córtex Auditivo/fisiologia , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Estimulação Acústica/métodos
7.
Anal Chem ; 96(22): 9270-9277, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38770656

RESUMO

Developing a specific, sensitive, rapid, and on-site method for detecting pathogenic bacteria in food samples is critical to ensuring public safety. This article demonstrates a CRISPR/Cas13a system and a chemiluminescence resonance energy transfer (CRET) (CRISPR/Cas 13a-assisted CRET)-based strategy for sensitive and on-site detection of pathogenic bacteria in real samples. Once the hybrid double strand of aptamerS. aureus-cRNA recognizes the target model bacteria of Staphylococcus aureus (S. aureus), the released cRNA would bind with CRISPR/Cas 13a to form a complex of cRNA-CRISPR/Cas 13a, which could cleave the RNA molecule in the detecting probe of horseradish peroxidase (HRP) modified-gold nanoparticles (AuNPs) linked by RNA (AuNPs-RNA-HRP), resulting in an enhanced chemiluminescence signal due to the CRET "OFF" phenomenon after introducing the chemiluminescence substrate of luminol. The CRISPR/Cas 13a-assisted CRET strategy successfully detected S. aureus in drinking water and milk with detection limits of 20 and 30 cfu/mL, respectively, within the recovery of 90.07-105.50%. Furthermore, after integrating with an immunochromatographic test strip (ICTS), the CRISPR/Cas 13a-assisted CRET strategy achieved the on-site detection of as low as 102 cfu/mL of S. aureus in drinking water and milk via a smartphone, which is about 10 times lower than that in the previously reported AuNPs-based colorimetric ICTS, demonstrating a convenient and sensitive detection method for S. aureus in real samples.


Assuntos
Sistemas CRISPR-Cas , Ouro , Leite , Staphylococcus aureus , Staphylococcus aureus/isolamento & purificação , Staphylococcus aureus/genética , Sistemas CRISPR-Cas/genética , Ouro/química , Leite/microbiologia , Animais , Medições Luminescentes , Água Potável/microbiologia , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , Limite de Detecção , Luminescência
8.
Small ; : e2402086, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38607305

RESUMO

Lithophobic Li2CO3/LiOH contaminants and high-resistance lithium-deficient phases produced from the exposure of garnet electrolyte to air leads to a decrease in electrolyte ion transfer ability. Additionally, garnet electrolyte grain boundaries (GBs) with narrow bandgap and high electron conductivity are potential channels for current leakage, which accelerate Li dendrites generation, ultimately leading to short-circuiting of all-solid-state batteries (ASSBs). Herein, a stably lithiophilic Li2ZO3 is in situ constructed at garnet electrolyte surface and GBs by interfacial modification with ZrO2 and Li2CO3 (Z+C) co-sintering to eliminate the detrimental contaminants and lithium-deficient phases. The Li2ZO3 formed on the modified electrolyte (LLZTO-(Z+C)) surface effectively improves the interfacial compatibility and air stability of the electrolyte. Li2ZO3 formed at GBs broadens the energy bandgaps of LLZTO-(Z+C) and significantly inhibits lithium dendrite generation. More Li+ transport paths found in LLZTO-Z+C by first-principles calculations increase Li+ conductivity from 1.04×10-4 to 7.45×10-4 S cm-1. Eventually, the Li|LLZTO-(Z+C)|Li symmetric cell maintains stable cycling for over 2000 h at 0.8 mA cm-2. The capacity retention of LiFePO4|LLZTO-(Z+C)|Li battery retains 70.5% after 5800 ultralong cycles at 4 C. This work provides a potential solution to simultaneously enhance the air stability and modulate chemical characteristics of the garnet electrolyte surface and GBs for ASSBs.

9.
RNA ; 28(1): 3-15, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34670847

RESUMO

This review covers research findings reported over the past decade concerning the ability of low complexity (LC) domains to self-associate in a manner leading to their phase separation from aqueous solution. We focus our message upon the reductionist use of two forms of phase separation as biochemical assays to study how LC domains might function in living cells. Cells and their varied compartments represent extreme examples of material condensates. Over the past half century, biochemists, structural biologists, and molecular biologists have resolved the mechanisms driving innumerable forms of macromolecular condensation. In contrast, we remain largely ignorant as to how 10%-20% of our proteins actually work to assist in cell organization. This enigmatic 10%-20% of the proteome corresponds to gibberish-like LC sequences. We contend that many of these LC sequences move in and out of a structurally ordered, self-associated state as a means of offering a combination of organizational specificity and dynamic pliability to living cells. Finally, we speculate that ancient proteins may have behaved similarly, helping to condense, organize, and protect RNA early during evolution.


Assuntos
Condensados Biomoleculares/química , Células Eucarióticas/química , Glicóis/química , Isoxazóis/química , Proteínas/química , RNA/química , Condensados Biomoleculares/metabolismo , Eucariotos , Células Eucarióticas/metabolismo , Hidrogéis/química , Hidrogéis/metabolismo , Ligação de Hidrogênio , Metionina/química , Metionina/metabolismo , Origem da Vida , Conformação Proteica em Folha beta , Domínios Proteicos , Proteínas/metabolismo , RNA/metabolismo , Soluções , Água/química , Água/metabolismo
10.
Respir Res ; 25(1): 148, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38555458

RESUMO

BACKGROUND: Astaxanthin (AXT) is a keto-carotenoid with a variety of biological functions, including antioxidant and antifibrotic effects. Small airway remodeling is the main pathology of chronic obstructive pulmonary disease (COPD) and is caused by epithelial-to-mesenchymal transition (EMT) and fibroblast differentiation and proliferation. Effective therapies are still lacking. This study aimed to investigate the role of AXT in small airway remodeling in COPD and its underlying mechanisms. METHODS: First, the model of COPD mice was established by cigarette smoke (CS) exposure combined with intraperitoneal injection of cigarette smoke extract (CSE). The effects of AXT on the morphology of CS combined with CSE -induced emphysema, EMT, and small airway remodeling by using Hematoxylin-eosin (H&E) staining, immunohistochemical staining, and western blot. In addition, in vitro experiments, the effects of AXT on CSE induced-EMT and fibroblast function were further explored. Next, to explore the specific mechanisms underlying the protective effects of AXT in COPD, potential targets of AXT in COPD were analyzed using network pharmacology. Finally, the possible mechanism was verified through molecular docking and in vitro experiments. RESULTS: AXT alleviated pulmonary emphysema, EMT, and small airway remodeling in a CS combined with CSE -induced mouse model. In addition, AXT inhibited the EMT process in airway cells and the differentiation and proliferation of fibroblasts. Mechanistically, AXT inhibited myofibroblast activation by directly binding to and suppressing the phosphorylation of AKT1. Therefore, our results show that AXT protects against small airway remodeling by inhibiting AKT1. CONCLUSIONS: The present study identified and illustrated a new food function of AXT, indicating that AXT could be used in the therapy of COPD-induced small airway remodeling.


Assuntos
Fumar Cigarros , Doença Pulmonar Obstrutiva Crônica , Enfisema Pulmonar , Camundongos , Animais , Fumar Cigarros/efeitos adversos , Remodelação das Vias Aéreas , Simulação de Acoplamento Molecular , Transdução de Sinais , Doença Pulmonar Obstrutiva Crônica/metabolismo , Enfisema Pulmonar/induzido quimicamente , Enfisema Pulmonar/tratamento farmacológico , Nicotiana/toxicidade , Xantofilas
11.
Respir Res ; 25(1): 66, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317159

RESUMO

BACKGROUND: Small airway remodelling is a vital characteristic of chronic obstructive pulmonary disease (COPD), which is mainly caused by epithelial barrier dysfunction and epithelial-mesenchymal transition (EMT). Recent studies have indicated that histone deacetylase 6 (HDAC6) plays an important role in the dysregulation of epithelial function. In this study, we investigated the therapeutic effects and underlying mechanisms of an inhibitor with high selectivity for HDAC6 in COPD. METHODS: Cigarette smoke (CS) exposure was used to establish a CS-induced COPD mouse model. CAY10603 at doses of 2.5 and 10 mg/kg was injected intraperitoneally on alternate days. The protective effects of CAY10603 against CS-induced emphysema, epithelial barrier function and small airway remodeling were evaluated using hematoxylin and eosin (H&E) staining, Masson's trichrome staining, immunohistochemical staining, and western blot. The human lung bronchial epithelial cell line (HBE) was used to elucidate the underlying molecular mechanism of action of CAY10603. RESULTS: HDAC6 levels in the lung homogenates of CS-exposed mice were higher than that those in control mice. Compared to the CS group, the mean linear intercept (MLI) of the CAY10603 treatment group decreased and the mean alveolar number (MAN)increased. Collagen deposition was reduced in groups treated with CAY10603. The expression of α-SMA was markedly upregulated in the CS group, which was reversed by CAY10603 treatment. Conversely, E-cadherin expression in the CS group was further downregulated, which was reversed by CAY10603 treatment. CAY10603 affects the tight junction protein expression of ZO-1 and occludin. ZO-1 and occludin expression were markedly downregulated in the CS group. After CAY10603treatment, the protein expression level of ZO-1 and occludin increased significantly. In HBE cells, Cigarette smoke extract (CSE) increased HDAC6 levels. CAY10603 significantly attenuated the release of TGF-ß1 induced by CSE. CAY10603 significantly increased the E-cadherin levels in TGF-ß1 treated HBE cells, while concurrently attenuated α-SMA expression. This effect was achieved through the suppression of Smad2 and Smad3 phosphorylation. CAY10603 also inhibited TGF-ß1 induced cell migration. CONCLUSIONS: These findings suggested that CAY10603 inhibited CS induced small airway remodelling by regulating epithelial barrier dysfunction and reversing EMT via the TGF-ß1/Smad2/3 signalling pathway.


Assuntos
Carbamatos , Fumar Cigarros , Oxazóis , Doença Pulmonar Obstrutiva Crônica , Animais , Humanos , Camundongos , Remodelação das Vias Aéreas , Caderinas/metabolismo , Fumar Cigarros/efeitos adversos , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Desacetilase 6 de Histona/metabolismo , Ocludina , Doença Pulmonar Obstrutiva Crônica/induzido quimicamente , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Doença Pulmonar Obstrutiva Crônica/metabolismo , Produtos do Tabaco , Fator de Crescimento Transformador beta1/metabolismo
12.
J Org Chem ; 89(10): 7169-7174, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38679873

RESUMO

α-succinimide-substituted allenoates were employed as phosphine acceptors in phosphine-catalyzed (4 + 2) annulation with 1,1-dicyanoalkenes. They served as C4 synthons in the annulation reaction under mild reaction conditions and produced hexahydroisoindole derivatives in moderate to high yields with good to excellent diastereoselectivities.

13.
Proc Natl Acad Sci U S A ; 118(8)2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33593918

RESUMO

Low complexity (LC) head domains 92 and 108 residues in length are, respectively, required for assembly of neurofilament light (NFL) and desmin intermediate filaments (IFs). As studied in isolation, these IF head domains interconvert between states of conformational disorder and labile, ß-strand-enriched polymers. Solid-state NMR (ss-NMR) spectroscopic studies of NFL and desmin head domain polymers reveal spectral patterns consistent with structural order. A combination of intein chemistry and segmental isotope labeling allowed preparation of fully assembled NFL and desmin IFs that could also be studied by ss-NMR. Assembled IFs revealed spectra overlapping with those observed for ß-strand-enriched polymers formed from the isolated NFL and desmin head domains. Phosphorylation and disease-causing mutations reciprocally alter NFL and desmin head domain self-association yet commonly impede IF assembly. These observations show how facultative structural assembly of LC domains via labile, ß-strand-enriched self-interactions may broadly influence cell morphology.


Assuntos
Desmina/química , Desmina/metabolismo , Filamentos Intermediários/química , Filamentos Intermediários/metabolismo , Humanos , Fosforilação , Conformação Proteica , Domínios Proteicos
14.
Proc Natl Acad Sci U S A ; 118(1)2021 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-33229555

RESUMO

The neural mechanisms underlying the impacts of noise on nonauditory function, particularly learning and memory, remain largely unknown. Here, we demonstrate that rats exposed postnatally (between postnatal days 9 and 56) to structured noise delivered at a sound pressure level of ∼65 dB displayed significantly degraded hippocampus-related learning and memory abilities. Noise exposure also suppressed the induction of hippocampal long-term potentiation (LTP). In parallel, the total or phosphorylated levels of certain LTP-related key signaling molecules in the synapses of the hippocampus were down-regulated. However, no significant changes in stress-related processes were found for the noise-exposed rats. These results in a rodent model indicate that even moderate-level noise with little effect on stress status can substantially impair hippocampus-related learning and memory by altering the plasticity of synaptic transmission. They support the importance of more thoroughly defining the unappreciated hazards of moderately loud noise in modern human environments.


Assuntos
Hipocampo/fisiologia , Aprendizagem/fisiologia , Memória/fisiologia , Ruído , Animais , Feminino , Potenciação de Longa Duração , Teste do Labirinto Aquático de Morris , Plasticidade Neuronal/fisiologia , Ratos , Ratos Sprague-Dawley , Sinapses/fisiologia , Transmissão Sináptica
15.
J Stroke Cerebrovasc Dis ; 33(4): 107634, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342274

RESUMO

BACKGROUND: Intracranial aneurysm (IA) is a common cerebrovascular disease and the leading cause of spontaneous subarachnoid hemorrhage. Recent evidence suggests that gut microbiota is involved in the pathophysiological process of IA through the gut-brain axis. However, the role of gut inflammation in the development of IA has yet to be clarified. Our study aimed to investigate whether fecal calprotectin (FC) level, a sensitive marker of gut inflammation, is correlated with the development of IA and the prognosis of patients with ruptured IA (RIA). METHODS: 182 patients were collected from January 2022 to January 2023, including 151 patients with IA and 31 healthy individuals. 151 IA patients included 109 patients with unruptured IA (UIA) and 42 patients with RIA. The FC level was measured by enzyme-linked immunosorbent assay. Other detailed information was obtained from an electronic medical record system. RESULTS: Compared with healthy controls, the FC levels in patients with IA were increased (P < 0.0001). Patients with RIA had significantly higher FC levels than UIA patients (P < 0.0001). Moreover, the FC level in RIA patients with unfavorable outcomes was higher than in RIA patients with favorable outcomes. Logistic regression analysis showed that the elevated FC level was an independent risk factor for a 3-month poor prognosis in patients with RIA (OR=1.005, 95% CI = 1.000 -1.009, P = 0.044). CONCLUSION: Fecal calprotectin level is significantly elevated in IA patients, especially those with RIA. FC is a novel biomarker of 3-month poor outcomes in RIA patients.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Hemorragia Subaracnóidea , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico , Hemorragia Subaracnóidea/etiologia , Aneurisma Roto/etiologia , Biomarcadores , Inflamação/complicações
16.
Molecules ; 29(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38893468

RESUMO

In this paper, an interesting γ'-carbon 1,6-conjugate addition for phosphine-catalyzed α-succinimide substituted allenoates has been disclosed. A wide array of substrates was found to participate in the reaction, resulting in the production of diverse 4-diarylmethylated 3,4-disubstituted maleimides with satisfactory to outstanding yields. Furthermore, a plausible mechanism for the reaction was proposed by the investigators.

17.
J Neurosci ; 42(45): 8556-8568, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36150889

RESUMO

An increasing number of studies have shown that cross-modal interaction can occur in early sensory cortices. Yet, how neurons in sensory cortices integrate multisensory cues in perceptual tasks and to what extent this influences behavior is largely unclear. To investigate, we examined visual modulation of auditory responses in the primary auditory cortex (A1) in a two-alternative forced-choice task. During the task, male rats were required to make a behavioral choice based on the pure tone frequency (low vs high) of the self-triggered stimulus to get a water reward. The result showed that the presence of a noninformative visual cue did not uniformly influence auditory response, with frequently enhancing just one of them. Closely correlated with behavioral choice, the visual cue mainly enhanced responsiveness to the auditory cue indicating a movement direction contralateral to A1 being recorded. Operating in this fashion provided A1 neurons a superior capability to discriminate sound during multisensory trials. Concomitantly, behavioral data and decoding analysis revealed that visual cue presence could speed the process of sound discrimination. We also observed this differential multisensory integration effect in well-trained rats when tested with passive stimulation and under anesthesia, albeit to a much lesser extent. We did not see this differentially integrative effect while recording in A1 in another similar group of rats performing a free-choice task. These data suggest that auditory cortex can engage in meaningful audiovisual processing, and perceptual learning can modify its multisensory integration mechanism to meet task requirements.SIGNIFICANCE STATEMENT In the natural environment, visual stimuli are frequently accompanied by auditory cues. Although multisensory integration has traditionally been seen as a feature of associational cortices, recent studies have shown that cross-modal inputs can also influence neuronal activity in primary sensory cortices. However, exactly how neurons in sensory cortices integrate multisensory cues to guide behavioral choice is still unclear. Here, we describe a novel model of multisensory integration used by A1 neurons to shape auditory representations when rats performed a cue-guided task. We found that a task-irrelevant visual cue could specifically enhance the response of neurons in sound guiding to the contralateral choice. This differentially integrative model facilitated sound discrimination and behavioral choice. This result indicates that task engagement can modulate multisensory integration.


Assuntos
Córtex Auditivo , Masculino , Ratos , Animais , Córtex Auditivo/fisiologia , Estimulação Acústica , Estimulação Luminosa , Percepção Auditiva/fisiologia , Discriminação Psicológica , Percepção Visual/fisiologia
18.
J Struct Biol ; 215(1): 107926, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36464198

RESUMO

Zinc transporter 8 (ZnT8) is mainly expressed in pancreatic islet ß cells and is responsible for H+-coupled uptake (antiport) of Zn2+ into the lumen of insulin secretory granules. Structures of human ZnT8 and its prokaryotic homolog YiiP have provided structural basis for constructing a plausible transport cycle for Zn2+. However, the mechanistic role that protons play in the transport process remains unclear. Here we present a lumen-facing cryo-EM structure of ZnT8 from Xenopus tropicalis (xtZnT8) in the presence of Zn2+ at a luminal pH (5.5). Compared to a Zn2+-bound xtZnT8 structure at a cytosolic pH (7.5), the low-pH structure displays an empty transmembrane Zn2+-binding site with a disrupted coordination geometry. Combined with a Zn2+-binding assay our data suggest that protons may disrupt Zn2+ coordination at the transmembrane Zn2+-binding site in the lumen-facing state, thus facilitating Zn2+ release from ZnT8 into the lumen.


Assuntos
Eucariotos , Prótons , Humanos , Microscopia Crioeletrônica , Concentração de Íons de Hidrogênio , Zinco
19.
Cancer ; 129(11): 1649-1661, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36857206

RESUMO

With the continuous cognition of the relationship between tumor cells and tumor immune microenvironment, immunotherapy based on the immune checkpoint blockade has achieved great breakthroughs, led to improved clinical outcomes, and prolonged survival for cancer patients in recent years. Nevertheless, the de novo or acquired resistance to immunotherapy has greatly counteracted the efficacy, leading to a 20%-40% overall response rate. Thus, further in-depth understanding of the regulation of the tumor microenvironment and antitumor immunity is urgently warranted. Ubiquitination-mediated protein degradation plays vital roles in protein stabilization, activation, and dynamics as well as in cellular homeostasis modulation. The dysregulated ubiquitination and deubiquitination are closely related to the changes in physiological and pathological processes, which subsequently result in a variety of diseases including cancer. In this review, the authors first summarize the current knowledge about the involvement of the ubiquitin-proteasome system in tumor development with the ubiquitin conjugation-regulated stability of p53, phosphatase and tensin homolog, and Myc protein as examples, then dissect the potential implications of ubiquitination-mediated immune checkpoints degradation in tumor microenvironment and immune responses, and finally discuss the effects of therapeutically targeting the ubiquitin-proteasome pathway on immunotherapy, with the goal of providing deep insights into the exploitation of more precise and effective combinational therapy against cancer.


Assuntos
Neoplasias , Ubiquitina , Humanos , Ubiquitina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Imunoterapia , Ubiquitinação , Neoplasias/patologia , Microambiente Tumoral
20.
Small ; 19(25): e2207324, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36932935

RESUMO

The construction of commercial surface enhanced Raman scattering (SERS) sensors suitable for clinical applications is a pending problem, which is heavily limited by the low production of high-performance SERS bases, because they usually require fine or complicated micro/nano structures. To solve this issue, herein, a promising mass-productive 4-inch ultrasensitive SERS substrate available for early lung cancer diagnosis is proposed, which is designed with a special architecture of particle in micro-nano porous structure. Benefitting from the effective cascaded electric field coupling inside the particle-in-cavity structure and efficient Knudsen diffusion of molecules within the nanohole, the substrate exhibits remarkable SERS performance for gaseous malignancy biomarker, with the limit of detection is 0.1 ppb and the average relative standard deviation value at different scales (from cm2 to µm2 ) is ≈16.5%. In practical application, this large-sized sensor can be further divided into small ones (1 × 1 cm2 ), and more than 65 chips will be obtained from just one 4-inch wafer, greatly increasing the output of commercial SERS sensor. Further, a medical breath bag composed of this small chip is designed and studied in detail here, which suggested high-specificity recognition for lung cancer biomarker in mixed mimetic exhalation tests.


Assuntos
Neoplasias Pulmonares , Nanopartículas Metálicas , Humanos , Nanopartículas Metálicas/química , Prata/química , Neoplasias Pulmonares/diagnóstico , Biomarcadores Tumorais , Análise Espectral Raman
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