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1.
Sci Rep ; 14(1): 15017, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951557

RESUMO

In recent years, clear aligner can enhance individual appearance with dental defects, so it used more and more widely. However, in manufacturing process, there are still some problems, such as low degree of automation and high equipment cost. The problem of coordinate system mismatch between gingival curve point cloud and dental CAD model is faced to. The PCA-ICP registration algorithm is proposed, which includes coarse match algorithm and improve-ICP registration algorithm. The principal component analysis (PCA) based method can roughly find the posture relationship between the two point clouds. Using z-level dynamic hierarchical, the ICP registration can accurately find the posture between these two clouds. The final registration maximum distance error is 0.03 mm, which is smaller than robot machining error. Secondly, the clear aligner machining process is conducted to verify the registration effectiveness. Before machining, the path is generated based on the well registered gingival curve. After full registration, the tool path is calculated by establishing a local coordinate system between the workpiece and the tool to avoid interference. This path is calculated and generated as an executable program for ABB industrial robots. Finally, the robot was used for flexible cutting of clear aligners and was able to extract products, ensuring the effectiveness of the proposed research. This method can effectively solve the limitations of traditional milling path planning under such complex conditions.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39004899

RESUMO

The development of perovskite direct X-ray detectors shows potential for advancing medical imaging and industrial inspection precision. To ensure the optimal energy conversion efficiency of X-rays for reducing radiation doses, it is necessary for perovskites with thicknesses reaching hundreds of micrometers or even several millimeters to be utilized. However, the nonlinear current response becomes uncertain with such high thicknesses. For instance, the prevailing theory regarding the rapid trapping and release of charges by shallow-level defects falls short in explaining the nonlinear current response observed in high-quality single-crystal samples. Moreover, a significant nonlinear current response can degrade the detection performance. Here, we elucidate peculiar parasitic and drift capacitance-induced nonlinear current responses in perovskites, which arise from bulk structural deficiencies and interface junction width variation in addition to shallow-level defects. Both theoretical analysis and experimental findings demonstrate the effective suppression of nonlinear current responses by establishing bulk heterojunctions and refining interface junctions. Consequently, we have successfully developed highly linear current-responsive detectors based on polycrystalline MAPbI3 thick films. Notably, these detectors achieve a record sensitivity of 2.3 × 104 µC·Gyair-1·cm-2 under 100 kVp X-ray irradiation with a low bias of 0.1 V/µm, enabling enduring and high-resolution X-ray imaging for high-density objects. Successful fabrication and testing of a 64 × 64-pixel flat-panel prototype detector affirm the widespread applicability of these strategies in rectifying nonlinear current responses in perovskite-based X-ray detectors.

3.
Biosens Bioelectron ; 263: 116552, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-39038400

RESUMO

Sulfadiazine (SDZ) is frequently detected in environmental samples, arousing much concern due to its toxicity and hard degradation. This study investigated the electricity generation capabilities, SDZ removal and microbial communities of a highly efficient mixed-culture system using repeated transfer enrichments in a bio-electrochemical system. The mixed-culture biofilm (S160-T2) produced a remarkable current density of 954.12 ± 15.08 µA cm-2 with 160 mg/L SDZ, which was 32.9 and 1.8 times higher than that of Geobacter sulfurreducens PCA with 40 mg/L SDZ and without additional SDZ, respectively. Especially, the impressive SDZ removal rate of 98.76 ± 0.79% was achieved within 96 h using the further acclimatized mixed-culture. The removal efficiency of this mixed-culture for SDZ through the bio-electrochemical system was 1.1 times higher than that using simple anaerobic biodegradation. Furthermore, the current density and removal efficiency in this system gradually decreased with increasing SDZ concentrations from 0 to 800 mg/L. In addition, community diversity data demonstrated that the dominant genera, Geobacter and Escherichia-Shigella, were enriched in mixed-culture biofilm, which might be responsible for the current production and SDZ removal. This work confirmed the important roles of acclimatized microbial consortia and co-substrates in the simultaneous removal of SDZ and electricity generation in an electrochemical system.

4.
Light Sci Appl ; 13(1): 161, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987253

RESUMO

Wireless sensing of the wave propagation direction from radio sources lays the foundation for communication, radar, navigation, etc. However, the existing signal processing paradigm for the direction of arrival estimation requires the radio frequency electronic circuit to demodulate and sample the multichannel baseband signals followed by a complicated computing process, which places the fundamental limit on its sensing speed and energy efficiency. Here, we propose the super-resolution diffractive neural networks (S-DNN) to process electromagnetic (EM) waves directly for the DOA estimation at the speed of light. The multilayer meta-structures of S-DNN generate super-oscillatory angular responses in local angular regions that can perform the all-optical DOA estimation with angular resolutions beyond the diffraction limit. The spatial-temporal multiplexing of passive and reconfigurable S-DNNs is utilized to achieve high-resolution DOA estimation over a wide field of view. The S-DNN is validated for the DOA estimation of multiple radio sources over 5 GHz frequency bandwidth with estimation latency over two to four orders of magnitude lower than the state-of-the-art commercial devices in principle. The results achieve the angular resolution over an order of magnitude, experimentally demonstrated with four times, higher than diffraction-limited resolution. We also apply S-DNN's edge computing capability, assisted by reconfigurable intelligent surfaces, for extremely low-latency integrated sensing and communication with low power consumption. Our work is a significant step towards utilizing photonic computing processors to facilitate various wireless sensing and communication tasks with advantages in both computing paradigms and performance over electronic computing.

5.
Anal Methods ; 16(26): 4255-4261, 2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38910452

RESUMO

Nanozymes have recently become a research hotspot because of the advantages of good stability, excellent catalytic performance and easy storage in comparison to natural enzymes. Nanozymes with oxidase-like activity get special attention because they needn't the participation of hydrogen peroxide. In this paper, poly(N-isopropylacrylamide) nanogel with oxidase-like activity was synthesized for the first time. The catalytic mechanism was explored by EPR and UV spectroscopy after adding specific trapping agents of ROS, and the results showed that PNIPAM NG can catalyze O2 to 1O2. In the presence of PNIPAM NG, o-phenylenediamine (OPD) and ascorbic acid (AA) can be oxidized to 2,3-diaminophenazine (oxOPD) and dehydroascorbic acid (DHA), and DHA can further react with OPD to produce a fluorescence substance. The colorimetric and fluorescence detection platforms for AA were constructed based on the above principles. Both platforms have satisfactory results in real samples. The fluorescence platform has better sensitivity and selectivity than the colorimetric platform.


Assuntos
Resinas Acrílicas , Ácido Ascórbico , Ácido Ascórbico/química , Resinas Acrílicas/química , Nanogéis/química , Colorimetria/métodos , Oxirredutases/química , Polietilenoimina/química , Polietilenoglicóis/química , Fenilenodiaminas/química , Espectrometria de Fluorescência/métodos , Catálise
6.
Inflammation ; 2024 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-38909344

RESUMO

Autoimmune diseases are typically characterized by aberrant activation of immune system that leads to excessive inflammatory reactions and tissue damage. Nevertheless, precise targeted and efficient therapies are limited. Thus, studies into novel therapeutic targets for the management of autoimmune diseases are urgently needed. Radical S-adenosyl methionine domain-containing 2 (RSAD2) is an interferon-stimulated gene (ISG) renowned for the antiviral properties of the protein it encodes, named viperin. An increasing number of studies have underscored the new roles of RSAD2/viperin in immunomodulation and mitochondrial metabolism. Previous studies have shown that there is a complex interplay between RSAD2/vipeirn and mitochondria and that binding of the iron-sulfur (Fe-S) cluster is necessary for the involvement of viperin in mitochondrial metabolism. Viperin influences the proliferation and development of immune cells as well as inflammation via different signaling pathways. However, the function of RSAD2/viperin varies in different studies and a comprehensive overview of this emerging theme is lacking. This review will describe the characteristics of RSAD2/viperin, decipher its function in immunometabolic processes, and clarify the crosstalk between RSAD2/viperin and mitochondria. Furthermore, we emphasize the crucial roles of RSAD2 in autoimmune diseases and its potential application value.

8.
RMD Open ; 10(2)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38942592

RESUMO

OBJECTIVES: To investigate the efficacy, safety, pharmacokinetics and pharmacodynamics of nipocalimab in participants with moderate to severe active rheumatoid arthritis (RA) and inadequate response or intolerance to ≥1 antitumour necrosis factor agent. METHODS: In this phase 2a study, participants with RA seropositive for anticitrullinated protein antibodies (ACPA) or rheumatoid factors were randomised 3:2 to nipocalimab (15 mg/kg intravenously every 2 weeks) or placebo from Weeks 0 to 10. Efficacy endpoints (primary endpoint: change from baseline in Disease Activity Score 28 using C reactive protein (DAS28-CRP) at Week 12) and patient-reported outcomes (PROs) were assessed through Week 12. Safety, pharmacokinetics and pharmacodynamics were assessed through Week 18. RESULTS: 53 participants were enrolled (nipocalimab/placebo, n=33/20). Although the primary endpoint did not reach statistical significance for nipocalimab versus placebo, a numerically higher change from baseline in DAS28-CRP at Week 12 was observed (least squares mean (95% CI): -1.03 (-1.66 to -0.40) vs -0.58 (-1.24 to 0.07)), with numerically higher improvements in all secondary efficacy outcomes and PROs. Serious adverse events were reported in three participants (burn infection, infusion-related reaction and deep vein thrombosis). Nipocalimab significantly and reversibly reduced serum immunoglobulin G, ACPA and circulating immune complex levels but not serum inflammatory markers, including CRP. ACPA reduction was associated with DAS28-CRP remission and 50% response rate in American College of Rheumatology (ACR) criteria; participants with a higher baseline ACPA had greater clinical improvement. CONCLUSIONS: Despite not achieving statistical significance in the primary endpoint, nipocalimab showed consistent, numerical efficacy benefits in participants with moderate to severe active RA, with greater benefit observed for participants with a higher baseline ACPA. TRIAL REGISTRATION NUMBER: NCT04991753.


Assuntos
Anticorpos Monoclonais Humanizados , Antirreumáticos , Artrite Reumatoide , Índice de Gravidade de Doença , Humanos , Artrite Reumatoide/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Resultado do Tratamento , Antirreumáticos/uso terapêutico , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Idoso , Adulto , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Método Duplo-Cego , Medidas de Resultados Relatados pelo Paciente , Anticorpos Antiproteína Citrulinada/sangue
9.
Cell Rep Med ; 5(7): 101624, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38942021

RESUMO

Prior studies indicate no correlation between the gut microbes of healthy first-degree relatives (HFDRs) of patients with Crohn's disease (CD) and the development of CD. Here, we utilize HFDRs as controls to examine the microbiota and metabolome in individuals with active (CD-A) and quiescent (CD-R) CD, thereby minimizing the influence of genetic and environmental factors. When compared to non-relative controls, the use of HFDR controls identifies fewer differential taxa. Faecalibacterium, Dorea, and Fusicatenibacter are decreased in CD-R, independent of inflammation, and correlated with fecal short-chain fatty acids (SCFAs). Validation with a large multi-center cohort confirms decreased Faecalibacterium and other SCFA-producing genera in CD-R. Classification models based on these genera distinguish CD from healthy individuals and demonstrate superior diagnostic power than models constructed with markers identified using unrelated controls. Furthermore, these markers exhibited limited discriminatory capabilities for other diseases. Finally, our results are validated across multiple cohorts, underscoring their robustness and potential for diagnostic and therapeutic applications.


Assuntos
Doença de Crohn , Microbioma Gastrointestinal , Humanos , Doença de Crohn/microbiologia , Doença de Crohn/genética , Feminino , Masculino , Adulto , Microbioma Gastrointestinal/genética , Fezes/microbiologia , Família , Pessoa de Meia-Idade , Estudos de Casos e Controles , Ácidos Graxos Voláteis/metabolismo , Adulto Jovem , Metaboloma , Microbiota/genética
10.
Am J Physiol Cell Physiol ; 327(2): C291-C309, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38826136

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are a family of "forever chemicals" including perfluorooctane sulfonate (PFOS). These toxic chemicals do not break down in the environment or in our bodies. In the human body, PFOS and perfluoroctanoic acid (PFOA) have a half-life (T1/2) of about 4-5 yr so low daily consumption of these chemicals can accumulate in the human body to a harmful level over a long period. Although the use of PFOS in consumer products was banned in the United States in 2022/2023, this forever chemical remains detectable in our tap water and food products. Every American tested has a high level of PFAS in their blood (https://cleanwater.org/pfas-forever-chemicals). In this report, we used a Sertoli cell blood-testis barrier (BTB) model with primary Sertoli cells cultured in vitro with an established functional tight junction (TJ)-permeability barrier that mimicked the BTB in vivo. Treatment of Sertoli cells with PFOS was found to perturb the TJ-barrier, which was the result of cytoskeletal disruption across the cell cytoplasm, disrupting actin and microtubule polymerization. These changes thus affected the proper localization of BTB-associated proteins at the BTB. Using RNA-Seq transcriptome profiling, bioinformatics analysis, and pertinent biochemical and cell biology techniques, it was discovered that PFOS -induced Sertoli cell toxicity through the c-Jun N-terminal kinase (JNK; also known as stress-activated protein kinase, SAPK) and its phosphorylated/active form p-JNK signaling pathway. More importantly, KB-R7943 mesylate (KB), a JNK/p-JNK activator, was capable of blocking PFOS-induced Sertoli cell injury, supporting the notion that PFOS-induced cell injury can possibly be therapeutically managed.NEW & NOTEWORTHY PFOS induces Sertoli cell injury, including disruption of the 1) blood-testis barrier function and 2) cytoskeletal organization, which, in turn, impedes male reproductive function. These changes are mediated by JNK/p-JNK signaling pathway. However, the use of KB-R7943, a JNK/p-JNK activator was capable of blocking PFOS-induced Sertoli cell injury, supporting the possibility of therapeutically managing PFOS-induced reproductive dysfunction.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Proteínas Quinases JNK Ativadas por Mitógeno , Células de Sertoli , Fluorocarbonos/toxicidade , Ácidos Alcanossulfônicos/toxicidade , Masculino , Animais , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/metabolismo , Células de Sertoli/patologia , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/genética , RNA-Seq , Barreira Hematotesticular/efeitos dos fármacos , Barreira Hematotesticular/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Junções Íntimas/patologia , Células Cultivadas , Camundongos , Ratos , Ratos Sprague-Dawley
11.
J Transl Med ; 22(1): 596, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38926764

RESUMO

BACKGROUND: Existing studies have found that circular RNAs (circRNAs) act as sponges for micro RNAs (miRNAs) to control downstream genes. However, the specific functionalities and mechanisms of circRNAs in human clear cell renal cell carcinoma (ccRCC) have yet to be thoroughly investigated. METHODS: Patient cohorts from online databases were used to screen candidate circRNAs, while another cohort from our hospital was obtained for validation. CircSOD2 was identified as a potential oncogenic target, and its relevant characteristics were investigated during ccRCC progression through various assays. A positive feedback loop containing downstream miRNA and its target gene were identified using bioinformatics and validated by luciferase reporter assays, RNA pull-down, and high-throughput sequencing. RESULTS: CircSOD2 expression was elevated in tumor samples and significantly correlated with overall survival (OS) and the tumor stage of ccRCC patients, which appeared in the enhanced proliferation, invasion, and migration of tumor cells. Through competitive binding to circSOD2, miR-532-3p can promote the expression of PAX5 and the progression of ccRCC, and such regulation can be salvaged by miR-532-3p inhibitor. CONCLUSION: A novel positive feedback loop, PAX5/circSOD2/miR-532-3p/PAX5 was identified in the study, indicating that the loop may play an important role in the diagnosis and prognostic prediction in ccRCC patients.


Assuntos
Carcinoma de Células Renais , Proliferação de Células , Retroalimentação Fisiológica , Regulação Neoplásica da Expressão Gênica , Neoplasias Renais , MicroRNAs , RNA Circular , Humanos , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , RNA Circular/genética , RNA Circular/metabolismo , Neoplasias Renais/genética , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Pessoa de Meia-Idade , Masculino , Carcinogênese/genética , Carcinogênese/patologia , Movimento Celular/genética , Fator de Transcrição PAX5/metabolismo , Fator de Transcrição PAX5/genética , Oncogenes/genética , Sequência de Bases , Progressão da Doença , Invasividade Neoplásica , Reprodutibilidade dos Testes
12.
J Orthop Translat ; 46: 103-115, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38841339

RESUMO

Background: Reactive oxygen species (ROS), predominantly generated by mitochondria, play a crucial role in the pathogenesis of intervertebral disc degeneration (IVDD). Reduction of ROS levels may be an effective strategy to delay IVDD. In this study, we assessed whether umbilical cord mesenchymal stem cell-exosomes (UCMSC-exos) can be used to treat IVDD by suppressing ROS production caused by mitochondrial dysfunction. Materials and methods: Human UCMSC-exos were isolated and identified. Nucleus pulposus cells (NPCs) were stimulated with H2O2 in the presence or absence of exosomes. Then, 4D label free quantitative (4D-LFQ) proteomics were used to analyze the differentially expressed (DE) proteins. Mitochondrial membrane potential (MMP), mitochondrial ROS and protein levels were determined via immunofluorescence staining, flow cytometry and western blotting respectively. Additionally, high-throughput sequencing was performed to identify the DE miRNAs in NPCs. Finally, therapeutic effects of UCMSC-exos were investigated in a puncture-induced IVDD rat model. Degenerative grades of rat IVDs were assessed using magnetic resonance imaging and histochemical staining. Results: UCMSC-exos effectively improved the viability of NPCs and restored the expression of the extracellular matrix (ECM) proteins, collagen type II alpha-1 (COL2A1) and matrix metalloproteinase-13 induced by H2O2. Additionally, UCMSC-exos not only reduced the total intracellular ROS and mitochondrial superoxide levels, but also increased MMP in pathological NPCs. 4D-LFQ proteomics and western blotting further revealed that UCMSC-exos up-regulated the levels of the mitochondrial protein, mitochondrial transcription factor A (TFAM), in H2O2-induced NPCs. High-throughput sequencing and qRT-PCR uncovered that UCMSC-exos down-regulated the levels of miR-194-5p, a potential negative regulator of TFAM, induced by H2O2. Finally, in vivo results showed that UCMSC-exos injection improved the histopathological structure and enhanced the expression levels of COL2A1 and TFAM in the rat IVDD model. Conclusions: Our findings suggest that UCMSC-exos promote ECM synthesis, relieve mitochondrial oxidative stress, and attenuate mitochondrial dysfunction in vitro and in vivo, thereby effectively treating IVDD. The translational potential of this article: This study provides solid experimental data support for the therapeutic effects of UCMSC-exos on IVDD, suggesting that UCMSC-exos will be a promising nanotherapy for IVDD.

13.
J Mol Cell Cardiol ; 194: 3-15, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38844061

RESUMO

Diabetic cardiomyopathy (DCM) is a heart failure syndrome, and is one of the major causes of morbidity and mortality in diabetes. DCM is mainly characterized by ventricular dilation, myocardial hypertrophy, myocardial fibrosis and cardiac dysfunction. Clinical studies have found that insulin resistance is an independent risk factor for DCM. However, its specific mechanism of DCM remains unclear. 8-hydroxyguanine DNA glycosylase 1(OGG1)is involved in DNA base repair and the regulation of inflammatory genes. In this study, we show that OGG1 was associated with the occurrence of DCM. for the first time. The expression of OGG1 was increased in the heart tissue of DCM mice, and OGG1 deficiency aggravated the cardiac dysfunction of DCM mice. Metabolomics show that OGG1 deficiency resulted in obstruction of glycolytic pathway. At the molecular level, OGG1 regulated glucose uptake and insulin resistance by interacting with PPAR-γ in vitro. In order to explore the protective effect of exogenous OGG1 on DCM, OGG1 adeno-associated virus was injected into DCM mice through tail vein in the middle stage of the disease. We found that the overexpression of OGG1 could improve cardiac dysfunction of DCM mice, indicating that OGG1 had a certain therapeutic effect on DCM. These results demonstrate that OGG1 is a new molecular target for the treatment of DCM and has certain clinical significance.

14.
Int Immunopharmacol ; 138: 112481, 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38917527

RESUMO

Systemic lupus erythematosus (SLE) is an intricate autoimmune disease with diverse manifestations. Immunometabolism reprogramming contributes to the progression of SLE by regulating the phenotype and function of immune cells. Dysregulated iron metabolism is implicated in SLE pathogenesis, affecting both systemic and immune cell-specific iron homeostasis. This review explores the systemic and cellular iron handling and regulation. Additionally, the advancements regarding iron metabolism in SLE with a focus on the distinct subsets of immune cells are highlighted. By gaining insight into the interplay between iron dysregulation and immune dysfunction, the potential therapeutic avenues may be unveiled. However, challenges remain in elucidating cell-specific iron metabolic reprogramming and its contribution to SLE pathogenesis needs further research for personalized therapeutic interventions and biomarker discovery. This review provides an in-depth understanding of immune cell-specific regulatory mechanisms of iron metabolism and new insights in current challenges as well as possible clinical applications.

15.
Nat Protoc ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745111

RESUMO

Microbial signatures have emerged as promising biomarkers for disease diagnostics and prognostics, yet their variability across different studies calls for a standardized approach to biomarker research. Therefore, we introduce xMarkerFinder, a four-stage computational framework for microbial biomarker identification with comprehensive validations from cross-cohort datasets, including differential signature identification, model construction, model validation and biomarker interpretation. xMarkerFinder enables the identification and validation of reproducible biomarkers for cross-cohort studies, along with the establishment of classification models and potential microbiome-induced mechanisms. Originally developed for gut microbiome research, xMarkerFinder's adaptable design makes it applicable to various microbial habitats and data types. Distinct from existing biomarker research tools that typically concentrate on a singular aspect, xMarkerFinder uniquely incorporates a sophisticated feature selection process, specifically designed to address the heterogeneity between different cohorts, extensive internal and external validations, and detailed specificity assessments. Execution time varies depending on the sample size, selected algorithm and computational resource. Accessible via GitHub ( https://github.com/tjcadd2020/xMarkerFinder ), xMarkerFinder supports users with diverse expertise levels through different execution options, including step-to-step scripts with detailed tutorials and frequently asked questions, a single-command execution script, a ready-to-use Docker image and a user-friendly web server ( https://www.biosino.org/xmarkerfinder ).

16.
Synth Syst Biotechnol ; 9(3): 600-608, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38774831

RESUMO

Streptomyces offer a wealth of naturally occurring compounds with diverse structures, many of which possess significant pharmaceutical values. However, new product exploration and increased yield of specific compounds in Streptomyces have been technically challenging due to their slow growth rate, complex culture conditions and intricate genetic backgrounds. In this study, we screened dozens of Streptomyces strains inhabiting in a plant rhizosphere for fast-growing candidates, and further employed CRISPR/Cas-based engineering techniques for stepwise refinement of a particular strain, Streptomyces sp. A-14 that harbors a 7.47 Mb genome. After strategic removal of nonessential genomic regions and most gene clusters, we reduced its genome size to 6.13 Mb, while preserving its growth rate to the greatest extent. We further demonstrated that cleaner metabolic background of this engineered strain was well suited for the expression and characterization of heterologous gene clusters, including the biosynthetic pathways of actinorhodin and polycyclic tetramate macrolactams. Moreover, this streamlined genome is anticipated to facilitate directing the metabolic flux towards the production of desired compounds and increasing their yields.

17.
bioRxiv ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38798592

RESUMO

Cell population delineation and identification is an essential step in single-cell and spatial-omics studies. Spatial-omics technologies can simultaneously measure information from three complementary domains related to this task: expression levels of a panel of molecular biomarkers at single-cell resolution, relative positions of cells, and images of tissue sections, but existing computational methods for performing this task on single-cell spatial-omics datasets often relinquish information from one or more domains. The additional reliance on the availability of "atlas" training or reference datasets limits cell type discovery to well-defined but limited cell population labels, thus posing major challenges for using these methods in practice. Successful integration of all three domains presents an opportunity for uncovering cell populations that are functionally stratified by their spatial contexts at cellular and tissue levels: the key motivation for employing spatial-omics technologies in the first place. In this work, we introduce Cell Spatio- and Neighborhood-informed Annotation and Patterning (CellSNAP), a self-supervised computational method that learns a representation vector for each cell in tissue samples measured by spatial-omics technologies at the single-cell or finer resolution. The learned representation vector fuses information about the corresponding cell across all three aforementioned domains. By applying CellSNAP to datasets spanning both spatial proteomic and spatial transcriptomic modalities, and across different tissue types and disease settings, we show that CellSNAP markedly enhances de novo discovery of biologically relevant cell populations at fine granularity, beyond current approaches, by fully integrating cells' molecular profiles with cellular neighborhood and tissue image information.

19.
Ecotoxicol Environ Saf ; 279: 116502, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38788563

RESUMO

BACKGROUND: Despite the known reproductive toxicity induced by triptolide (TP) exposure, the regulatory mechanism underlying testicular vacuolization injury caused by TP remains largely obscure. METHODS: Male mice were subjected to TP at doses of 15, 30, and 60 µg/kg for 35 consecutive days. Primary Sertoli cells were isolated from 20-day-old rat testes and exposed to TP at concentrations of 0, 40, 80, 160, 320, and 640 nM. A Biotin tracer assay was conducted to assess the integrity of the blood-testis barrier (BTB). Transepithelial electrical resistance (TER) assays were employed to investigate BTB function in primary Sertoli cells. Histological structures of the testes and epididymides were stained with hematoxylin and eosin (H&E). The expression and localization of relevant proteins or pathways were assessed through Western blotting or immunofluorescence staining. RESULTS: TP exposure led to dose-dependent testicular injuries, characterized by a decreased organ coefficient, reduced sperm concentration, and the formation of vacuolization damage. Furthermore, TP exposure disrupted BTB integrity by reducing the expression levels of tight junction (TJ) proteins in the testes without affecting basal ectoplasmic specialization (basal ES) proteins. Through the TER assay, we identified that a TP concentration of 160 nM was optimal for elucidating BTB function in primary Sertoli cells, correlating with reductions in TJ protein expression. Moreover, TP exposure induced changes in the distribution of the BTB and cytoskeleton-associated proteins in primary Sertoli cells. By activating the AKT/mTOR signaling pathway, TP exposure disturbed the balance between mTORC1 and mTORC2, ultimately compromising BTB integrity in Sertoli cells. CONCLUSION: This investigation sheds light on the impacts of TP exposure on testes, elucidating the mechanism by which TP exposure leads to testicular vacuolization injury and offering valuable insights into comprehending the toxic effects of TP exposure on testes.


Assuntos
Barreira Hematotesticular , Citoesqueleto , Diterpenos , Compostos de Epóxi , Fenantrenos , Proteínas Proto-Oncogênicas c-akt , Células de Sertoli , Transdução de Sinais , Serina-Treonina Quinases TOR , Testículo , Masculino , Animais , Células de Sertoli/efeitos dos fármacos , Células de Sertoli/patologia , Diterpenos/toxicidade , Fenantrenos/toxicidade , Serina-Treonina Quinases TOR/metabolismo , Transdução de Sinais/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/patologia , Compostos de Epóxi/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Camundongos , Barreira Hematotesticular/efeitos dos fármacos , Barreira Hematotesticular/patologia , Citoesqueleto/efeitos dos fármacos , Ratos , Vacúolos/efeitos dos fármacos , Ratos Sprague-Dawley
20.
J Ophthalmol ; 2024: 7197249, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38529362

RESUMO

Purpose: To evaluate the efficacy of spironolactone in the treatment of chronic central serous chorioretinopathy (CSC) and identify imaging characteristics that can predict the benefit of spironolactone treatment. Methods: Patients with chronic CSC were treated with spironolactone (20 mg/tid) and followed for 6 months. The primary outcome measure was complete resolution of the subretinal fluid (SRF), and the best-corrected visual acuity (BCVA), the SRF area, the central macular thickness (CMT), the subfoveal choroidal thickness (SFCT), and the density of the choriocapillaris vessel and adverse events were secondary outcome measures. Patients who presented complete resolution of SRF were included in the responder group and the other patients who had moderate or no resolution were included in the nonresponder group. Imaging characteristic comparisons between the responder and nonresponder groups were performed with regression analyses to identify factors that are predictive of a good response to treatment. Results: Forty-two eyes of 42 patients with a mean age of 46.06 ± 6.66 years were included. A total of 57.1% of the patients achieved a complete resolution of SRF. The mean SRF area, CMT, and SFCT decreased significantly (all P < 0.05) throughout the follow-up period and BCVA improved slightly (P > 0.05). The vascular density of the choriocapillaris of the fellow eyes did not vary significantly during treatment. Logistic regression analysis revealed that SFCT (P=0.002) and the intact ellipsoid zone (P=0.001) were correlated with disease resolution. A relatively higher baseline SFCT was a predictive factor associated with a good response to treatment according to multivariate analysis. Conclusions: This study suggested that oral spironolactone could be an effective and safe therapy for chronic CSC patients. Eyes with a higher baseline SFCT and intact ellipsoid zone could have a good response. These parameters are an important prognostic marker.

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