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1.
Proc Natl Acad Sci U S A ; 121(11): e2318320121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38457518

RESUMO

Coordinated carbon and nitrogen metabolism is crucial for bacteria living in the fluctuating environments. Intracellular carbon and nitrogen homeostasis is maintained by a sophisticated network, in which the widespread signaling protein PII acts as a major regulatory hub. In cyanobacteria, PII was proposed to regulate the nitrate uptake by an ABC (ATP-binding cassette)-type nitrate transporter NrtABCD, in which the nucleotide-binding domain of NrtC is fused with a C-terminal regulatory domain (CRD). Here, we solved three cryoelectron microscopy structures of NrtBCD, bound to nitrate, ATP, and PII, respectively. Structural and biochemical analyses enable us to identify the key residues that form a hydrophobic and a hydrophilic cavity along the substrate translocation channel. The core structure of PII, but not the canonical T-loop, binds to NrtC and stabilizes the CRD, making it visible in the complex structure, narrows the substrate translocation channel in NrtB, and ultimately locks NrtBCD at an inhibited inward-facing conformation. Based on these results and previous reports, we propose a putative transport cycle driven by NrtABCD, which is allosterically inhibited by PII in response to the cellular level of 2-oxoglutarate. Our findings provide a distinct regulatory mechanism of ABC transporter via asymmetrically binding to a signaling protein.


Assuntos
Cianobactérias , Transportadores de Nitrato , Nitratos/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Alostérica , Microscopia Crioeletrônica , Cianobactérias/metabolismo , Trifosfato de Adenosina/metabolismo , Nitrogênio/metabolismo , Carbono/metabolismo , Proteínas PII Reguladoras de Nitrogênio/genética , Proteínas PII Reguladoras de Nitrogênio/metabolismo
2.
Exp Cell Res ; 434(1): 113857, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38008278

RESUMO

Genetic factors coordinate with environmental factors to drive the pathogenesis of prostate adenocarcinoma (PRAD). SPOP is one of the most mutated genes and LRP5 mediates lipid metabolism that is abnormally altered in PRAD. Here, we investigated the potential cross-talk between SPOP and LRP5 in PRAD. We find a negative correlation between SPOP and LRP5 proteins in PRAD. SPOP knockdown increased LRP5 protein while SPOP overexpression resulted in LRP5 reduction that was fully rescued by proteasome inhibitors. LRP5 intracellular tail has SPOP binding site and the direct interaction between LRP5 and SPOP was confirmed by Co-IP and GST-pulldown. Moreover, LRP5 competed with Daxx for SPOP-mediated degradation, establishing a dynamic balance among SPOP, LRP5 and Daxx. Overexpression of LRP5 tail could shift this balance to enhance Daxx-mediated transcriptional inhibition, and inhibit T cell activity in a co-culture system. Further, we generated human and mouse prostate cancer cell lines expressing SPOP variants (F133V, A227V, R368H). SPOP-F133V and SPOP-A227V have specific effects in up-regulating the protein levels of PD-1 and PD-L1. Consistently, SPOP-F133V and SPOP-A227V show robust inhibitory effects on T cells compared to WT SPOP in co-culture. This is further supported by the mouse syngeneic model showing that SPOP-F133V and SPOP-A227V enhance tumorigenesis of prostate cancer in in-vivo condition. Taken together, our study provides evidence that SPOP-LRP5 crosstalk plays an essential role, and the genetic variants of SPOP differentially modulate the expression and activity of immune checkpoints in prostate cancer.


Assuntos
Neoplasias da Próstata , Proteínas Repressoras , Masculino , Animais , Camundongos , Humanos , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Antígeno B7-H1/genética , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Neoplasias da Próstata/patologia , Carcinogênese/genética , Transformação Celular Neoplásica , Mutação , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Chaperonas Moleculares/genética , Proteínas Correpressoras/genética
3.
Nano Lett ; 24(37): 11661-11668, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39250914

RESUMO

Fluorescent nanodiamonds (FNDs) with nitrogen-vacancy centers are pivotal for advancing quantum photonics and imaging through deterministic quantum state manipulation. However, deterministic integration of quantum emitters into photonic devices remains a challenge due to the need for high coupling efficiency and Purcell enhancement. We report a deterministic FND-integrated nanofocusing device achieved by assembling FNDs at a plasmonic waveguide tip through plasmonic-enhanced optical trapping. This technique not only increases the emission rate by 58.6 times compared to isolated FNDs but also preferentially directs radiation into the waveguide at a rate 5.3 times higher than that into free space, achieving an exceptional figure-of-merit of ∼3000 for efficient energy transfer. Our findings represent a significant step toward deterministic integration in quantum imaging and communication, opening new avenues for quantum technology advancements.

4.
J Struct Biol ; 216(2): 108072, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38431179

RESUMO

Efficient and high-accuracy filtering of cryo-electron microscopy (cryo-EM) micrographs is an emerging challenge with the growing speed of data collection and sizes of datasets. Convolutional neural networks (CNNs) are machine learning models that have been proven successful in many computer vision tasks, and have been previously applied to cryo-EM micrograph filtering. In this work, we demonstrate that two strategies, fine-tuning models from pretrained weights and including the power spectrum of micrographs as input, can greatly improve the attainable prediction accuracy of CNN models. The resulting software package, Miffi, is open-source and freely available for public use (https://github.com/ando-lab/miffi).


Assuntos
Microscopia Crioeletrônica , Processamento de Imagem Assistida por Computador , Redes Neurais de Computação , Software , Microscopia Crioeletrônica/métodos , Processamento de Imagem Assistida por Computador/métodos , Aprendizado de Máquina , Algoritmos
5.
Oncologist ; 29(4): e487-e497, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37874924

RESUMO

BACKGROUND: The difference in the prognoses between treatment with surgical therapy and continuation of local-plus-systemic therapy following successful down-staging of intermediate-advanced hepatocellular carcinoma (HCC) remains unclear. METHODS: Data of 405 patients with intermediate-advanced HCC treated at 30 hospitals across China from January 2017 to July 2022 were retrospectively reviewed. All patients received local-plus-systemic therapy and were divided into the surgical (n = 100) and nonsurgical groups (n = 305) according to whether they received surgical therapy. The differences between long-term prognoses of the 2 groups were compared. Subgroup analysis was performed in 173 HCC patients who met the criteria for surgical resection following down-staging. RESULTS: Multivariable analysis of all patients showed that surgical therapy, hazard ratio (HR): 0.289, 95% confidence interval, CI, 0.136-0.613) was a protective factor for overall survival (OS), but not for event-free survival (EFS). Multivariable analysis of 173 intermediate-advanced HCC patients who met the criteria for surgical resection after conversion therapy showed that surgical therapy (HR: 0.282, 95% CI, 0.121-0.655) was a protective factor for OS, but not for EFS. Similar results were obtained after propensity score matching. For patients with Barcelona Clinic Liver Cancer stage B (HR: 0.171, 95% CI, 0.039-0.751) and C (HR: 0.269, 95% CI, 0.085-0.854), surgical therapy was also a protective factor for OS. CONCLUSIONS: Overall, for patients with intermediate-advanced HCC who underwent local-plus-systemic therapies, surgical therapy is a protective factor for long-term prognosis and can prolong OS, and for those who met the surgical resection criteria after conversion therapy, surgical therapy is recommended.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/patologia , Estudos Retrospectivos , Estadiamento de Neoplasias , Prognóstico , Hepatectomia
6.
Org Biomol Chem ; 22(37): 7702-7706, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39224970

RESUMO

The development of facile and convenient atom-economical methods for the preparation of organosulfur compounds from CS2 is a challenging endeavor. Herein, a one-pot, environmentally friendly method to access S-aryl/alkyl dithiocarbamates has been demonstrated by a three-component coupling involving aryl/alkyl thiols, CS2 and amines in the presence of a common base K2CO3. The transformation process can proceed in an H2O-DMAc (3 : 1) mixed solvent without requiring any catalysts or extensive prefunctionalization of reactants. The protocol is operationally simple and affords dithiocarbamates with various moieties (including aryl, aliphatic, heteroaryl and alkenyl) in good yields.

7.
Nutr J ; 23(1): 104, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39252042

RESUMO

BACKGROUND: The fat-to-muscle mass ratio (FMR), integrating the antagonistic effects of fat and muscle mass, has been suggested as a valuable indicator to assess cardiometabolic health independent of overall adiposity. However, the specific associations of total and regional FMR with cardiometabolic risk are poorly understood. We aimed to examine sex-specific associations of total and regional FMR with single and clustered cardiometabolic risk factors (CRFs). METHODS: 13,505 participants aged 20 years and above were included in the cross-sectional study. Fat mass and muscle mass were assessed using a bioelectrical impedance analysis device. FMR was estimated as fat mass divided by muscle mass in corresponding body parts (whole body, arm, leg, and trunk). Clustered CRFs was defined as the presence of two or more risk factors, including hypertension, elevated blood glucose, dyslipidemia, insulin resistance (IR), and hyperuricemia. IR was assessed by the triglyceride glucose (TyG) index. Multivariable logistic regression models were applied to explore the associations of FMR in the whole body and body parts with single and clustered CRFs. RESULTS: The odds ratios (ORs) increased significantly for all single and clustered CRFs with the per quartile increase of total and regional FMR in both sexes (P for trend < 0.001), following adjustment for confounders. Among the regional parts, FMRs of the legs presented the strongest associations for clustered CRFs in both men and women, with adjusted OR of 8.54 (95% confidence interval (CI): 7.12-10.24) and 4.92 (95% CI: 4.24-5.71), respectively. Significant interactions (P for interaction < 0.05) were identified between age and FMRs across different body parts, as well as between BMI status and FMRs in different regions for clustered CRFs. Restricted cubic splines revealed significant non-linear relationships between FMRs of different body parts and clustered CRFs in both sexes (P for nonlinear < 0.05). CONCLUSIONS: FMRs in the whole body and different regions were significantly associated with single and clustered CRFs in the general Chinese population. The association between FMR and clustered CRFs was more pronounced in youngers than in the elderly.


Assuntos
Fatores de Risco Cardiometabólico , Inquéritos Epidemiológicos , Humanos , Masculino , Feminino , China/epidemiologia , Estudos Transversais , Adulto , Pessoa de Meia-Idade , Inquéritos Epidemiológicos/estatística & dados numéricos , Inquéritos Epidemiológicos/métodos , Fatores Sexuais , Tecido Adiposo , Músculo Esquelético , Adiposidade , Composição Corporal , Adulto Jovem , Fatores de Risco , Idoso , Resistência à Insulina , Doenças Cardiovasculares/epidemiologia
8.
Int J Med Sci ; 21(6): 1176-1186, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38774752

RESUMO

Background: To uncover the potential significance of JAK-STAT-SOCS1 axis in penile cancer, our study was the pioneer in exploring the altered expression processes of JAK-STAT-SOCS1 axis in tumorigenesis, malignant progression and lymphatic metastasis of penile cancer. Methods: In current study, the comprehensive analysis of JAK-STAT-SOCS1 axis in penile cancer was analyzed via multiple analysis approaches based on GSE196978 data, single-cell data (6 cancer samples) and bulk RNA data (7 cancer samples and 7 metastasis lymph nodes). Results: Our study observed an altered molecular expression of JAK-STAT-SOCS1 axis during three different stages of penile cancer, from tumorigenesis to malignant progression to lymphatic metastasis. STAT4 was an important dominant molecule in penile cancer, which mediated the immunosuppressive tumor microenvironment by driving the apoptosis of cytotoxic T cell and was also a valuable biomarker of immune checkpoint inhibitor treatment response. Conclusions: Our findings revealed that the complexity of JAK-STAT-SOCS1 axis and the predominant role of STAT4 in penile cancer, which can mediate tumorigenesis, malignant progression, and lymphatic metastasis. This insight provided valuable information for developing precise treatment strategies for patients with penile cancer.


Assuntos
Progressão da Doença , Janus Quinases , Metástase Linfática , Neoplasias Penianas , Fator de Transcrição STAT4 , Proteína 1 Supressora da Sinalização de Citocina , Humanos , Masculino , Neoplasias Penianas/patologia , Neoplasias Penianas/genética , Neoplasias Penianas/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/genética , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Metástase Linfática/patologia , Metástase Linfática/genética , Janus Quinases/metabolismo , Fator de Transcrição STAT4/metabolismo , Fator de Transcrição STAT4/genética , Regulação Neoplásica da Expressão Gênica , Carcinogênese/genética , Carcinogênese/patologia , Transdução de Sinais , Microambiente Tumoral/imunologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/farmacologia
9.
Skin Res Technol ; 30(4): e13693, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572573

RESUMO

BACKGROUND: To further clarify the acne profile of Chinese adult women, we included 1,156,703 adult women. An artificial intelligence algorithm was used to analyze images taken by high-resolution mobile phones to further explore acne levels in Chinese adult women. METHOD: In this study, we assessed the severity of acne by evaluating patients' selfies through a smartphone application. Furthermore, we gathered basic user information through a questionnaire, including details such as age, gender, skin sensitivity, and dietary habits. RESULTS: This study showed a gradual decrease in acne severity from the age of 25 years. A trough was reached between the ages of 40 and 44, followed by a gradual increase in acne severity. In terms of skin problems and acne severity, we have found that oily skin, hypersensitive skin, frequent makeup application and unhealthy dietary habits can affect the severity of acne. For environment and acne severity, we observed that developed city levels, cold seasons and high altitude and strong radiation affect acne severity in adult women. For the results of the AI analyses, the severity of blackheads, pores, dark circles and skin roughness were positively associated with acne severity in adult women. CONCLUSIONS: AI analysis of high-res phone images in Chinese adult women reveals acne severity trends. Severity decreases after 25, hits a low at 40-44, then gradually rises. Skin type, sensitivity, makeup, diet, urbanization, seasons, altitude, and radiation impact acne. Blackheads, pores, dark circles, and skin roughness are linked to acne severity. These findings inform personalized skincare and public health strategies for adult women.


Assuntos
Acne Vulgar , Inteligência Artificial , Adulto , Humanos , Feminino , Acne Vulgar/epidemiologia , Acne Vulgar/complicações , Pele , China/epidemiologia
10.
BMC Oral Health ; 24(1): 625, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38807101

RESUMO

BACKGROUND: Oral squamous cell cancer (OSCC) is a prevalent malignancy in oral cavity, accounting for nearly 90% of oral malignancies. It ranks sixth among the most common types of cancer worldwide and is responsible for approximately 145,000 deaths each year. It is widely accepted that noncoding RNAs participate cancer development in competitive regulatory interaction, knowing as competing endogenous RNA (ceRNA) network, whereby long non-coding RNA (lncRNA) function as decoys of microRNAs to regulate gene expression. LncRNA FOXD2-AS1 was reported to exert an oncogenic role in OSCC. Nevertheless, the ceRNA network mediated by FOXD2-AS1 was not investigated yet. This study aimed to explore the effect of FOXD2-AS1 on OSCC cell process and the underlying ceRNA mechanism. METHODS: FOXD2-AS1 expression in OSCC cells were determined via reverse transcription and quantitative polymerase chain reaction. Short hairpin RNA targeting FOXD2-AS1 was transfected into OSCC cells to silence FOXD2-AS1 expression. Then, loss-of-function experiments (n = 3 each assay) were performed to measure cell proliferation, apoptosis, migration, and invasion using colony formation, TdT-mediated dUTP Nick-End Labeling, wound healing and Transwell assays, respectively. RNA binding relation was verified by RNA immunoprecipitation and luciferase reporter assays. Rescue experiments were designed to validate whether FOXD2-AS1 affects cell behavior via the gene cellular retinoic acid binding protein 2 (CRABP2). Statistics were processed by GraphPad Prism 6.0 Software and SPSS software. RESULTS: FOXD2-AS1 was significantly upregulated in Cal27 and SCC9 cells (6.8 and 6.4 folds). In response to FOXD2-AS1 knockout, OSCC cell proliferation, migration and invasion were suppressed (approximately 50% decrease) while OSCC cell apoptosis was enhanced (more than two-fold increase). FOXD2-AS1 interacted with miR-378 g to alter CRABP2 expression. CRABP2 upregulation partly rescued (*p < 0.05, **p < 0.01, ***p < 0.001) the inhibitory impact of FOXD2-AS1 depletion on malignant characteristics of OSCC cells. CONCLUSION: FOXD2-AS1 enhances OSCC malignant cell behaviors by interacting with miR-378 g to regulate CRABP2 expression.


Assuntos
Carcinoma de Células Escamosas , MicroRNAs , Neoplasias Bucais , RNA Longo não Codificante , Humanos , Apoptose/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , MicroRNAs/genética , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Neoplasias Bucais/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
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