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1.
Chem Rev ; 123(22): 12471-12506, 2023 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-37931070

RESUMO

Serving as the basis of cell life, interactions between nucleic acids and proteins play essential roles in fundamental cellular processes. Aptamers are unique single-stranded oligonucleotides generated by in vitro evolution methods, possessing the ability to interact with proteins specifically. Altering the structure of aptamers will largely modulate their interactions with proteins and further affect related cellular behaviors. Recently, with the in-depth research of aptamer-protein interactions, the analytical assays based on their interactions have been widely developed and become a powerful tool for biomolecular detection. There are some insightful reviews on aptamers applied in protein detection, while few systematic discussions are from the perspective of regulating aptamer-protein interactions. Herein, we comprehensively introduce the methods for regulating aptamer-protein interactions and elaborate on the detection techniques for analyzing aptamer-protein interactions. Additionally, this review provides a broad summary of analytical assays based on the regulation of aptamer-protein interactions for detecting biomolecules. Finally, we present our perspectives regarding the opportunities and challenges of analytical assays for biological analysis, aiming to provide guidance for disease mechanism research and drug discovery.


Assuntos
Aptâmeros de Nucleotídeos , Ácidos Nucleicos , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Proteínas , Técnica de Seleção de Aptâmeros/métodos
2.
PLoS Genet ; 18(9): e1010425, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36149892

RESUMO

Transcriptional elongation is a universal and critical step during gene expression. The super elongation complex (SEC) regulates the rapid transcriptional induction by mobilizing paused RNA polymerase II (Pol II). Dysregulation of SEC is closely associated with human diseases. However, the physiological role of SEC during development and homeostasis remains largely unexplored. Here we studied the function of SEC in adipogenesis by manipulating an essential scaffold protein AF4/FMR2 family member 4 (AFF4), which assembles and stabilizes SEC. Knockdown of AFF4 in human mesenchymal stem cells (hMSCs) and mouse 3T3-L1 preadipocytes inhibits cellular adipogenic differentiation. Overexpression of AFF4 enhances adipogenesis and ectopic adipose tissue formation. We further generate Fabp4-cre driven adipose-specific Aff4 knockout mice and find that AFF4 deficiency impedes adipocyte development and white fat depot formation. Mechanistically, we discover AFF4 regulates autophagy during adipogenesis. AFF4 directly binds to autophagy-related protein ATG5 and ATG16L1, and promotes their transcription. Depleting ATG5 or ATG16L1 abrogates adipogenesis in AFF4-overepressing cells, while overexpression of ATG5 and ATG16L1 rescues the impaired adipogenesis in Aff4-knockout cells. Collectively, our results unveil the functional importance of AFF4 in regulating autophagy and adipogenic differentiation, which broaden our understanding of the transcriptional regulation of adipogenesis.


Assuntos
Adipogenia , Fatores de Elongação da Transcrição/metabolismo , Adipogenia/genética , Animais , Autofagia/genética , Proteínas Relacionadas à Autofagia/genética , Diferenciação Celular/genética , Humanos , Camundongos , RNA Polimerase II , Fatores de Transcrição , Fatores de Elongação da Transcrição/genética
3.
Proc Natl Acad Sci U S A ; 119(34): e2204256119, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35972965

RESUMO

Antibody therapeutics for the treatment of COVID-19 have been highly successful. However, the recent emergence of the Omicron variant has posed a challenge, as it evades detection by most existing SARS-CoV-2 neutralizing antibodies (nAbs). Here, we successfully generated a panel of SARS-CoV-2/SARS-CoV cross-neutralizing antibodies by sequential immunization of the two pseudoviruses. Of the potential candidates, we found that nAbs X01, X10, and X17 offer broad neutralizing potential against most variants of concern, with X17 further identified as a Class 5 nAb with undiminished neutralization against the Omicron variant. Cryo-electron microscopy structures of the three antibodies together in complex with each of the spike proteins of the prototypical SARS-CoV, SARS-CoV-2, and Delta and Omicron variants of SARS-CoV-2 defined three nonoverlapping conserved epitopes on the receptor-binding domain. The triple-antibody mixture exhibited enhanced resistance to viral evasion and effective protection against infection of the Beta variant in hamsters. Our findings will aid the development of antibody therapeutics and broad vaccines against SARS-CoV-2 and its emerging variants.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Epitopos , SARS-CoV-2 , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , Sequência Conservada , Cricetinae , Microscopia Crioeletrônica , Epitopos/imunologia , Humanos , Camundongos , Testes de Neutralização , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética
4.
Nano Lett ; 24(28): 8558-8566, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38847360

RESUMO

In laser-based additive manufacturing (AM), porosity and unmelted metal powder are typically considered undesirable and harmful. Nevertheless in this work, precisely controlling laser parameters during printing can intentionally introduce controllable porosity, yielding a porous electrode with enhanced catalytic activity for the oxygen evolution reaction (OER). This study demonstrates that deliberate introduction of porosity, typically considered a defect, leads to improved gas molecule desorption, enhanced mass transfer, and increased catalytically active sites. The optimized P-93% electrode displays superior OER performance with an overpotential of 270 mV at 20 mA cm-2. Furthermore, it exhibits remarkable long-term stability, operating continuously for over 1000 h at 10 mA cm-2 and more than 500 h at 500 mA cm-2. This study not only provides a straightforward and mass-producible method for efficient, binder-free OER catalysts but also, if optimized, underscores the potential of laser-based AM driven defect engineering as a promising strategy for industrial water splitting.

5.
J Cell Mol Med ; 28(8): e18292, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38652116

RESUMO

Foodborne illnesses, particularly those caused by Salmonella enterica with its extensive array of over 2600 serovars, present a significant public health challenge. Therefore, prompt and precise identification of S. enterica serovars is essential for clinical relevance, which facilitates the understanding of S. enterica transmission routes and the determination of outbreak sources. Classical serotyping methods via molecular subtyping and genomic markers currently suffer from various limitations, such as labour intensiveness, time consumption, etc. Therefore, there is a pressing need to develop new diagnostic techniques. Surface-enhanced Raman spectroscopy (SERS) is a non-invasive diagnostic technique that can generate Raman spectra, based on which rapid and accurate discrimination of bacterial pathogens could be achieved. To generate SERS spectra, a Raman spectrometer is needed to detect and collect signals, which are divided into two types: the expensive benchtop spectrometer and the inexpensive handheld spectrometer. In this study, we compared the performance of two Raman spectrometers to discriminate four closely associated S. enterica serovars, that is, S. enterica subsp. enterica serovar dublin, enteritidis, typhi and typhimurium. Six machine learning algorithms were applied to analyse these SERS spectra. The support vector machine (SVM) model showed the highest accuracy for both handheld (99.97%) and benchtop (99.38%) Raman spectrometers. This study demonstrated that handheld Raman spectrometers achieved similar prediction accuracy as benchtop spectrometers when combined with machine learning models, providing an effective solution for rapid, accurate and cost-effective identification of closely associated S. enterica serovars.


Assuntos
Salmonella enterica , Sorogrupo , Análise Espectral Raman , Máquina de Vetores de Suporte , Análise Espectral Raman/métodos , Salmonella enterica/isolamento & purificação , Humanos , Algoritmos
6.
J Am Chem Soc ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38982560

RESUMO

The disturbance of potassium current in cardiac myocytes caused by potassium channel dysfunction can lead to cardiac electrophysiological disorders, resulting in associated cardiovascular diseases. The emergence of artificial potassium ion channels opens up a way to replace dysfunctional natural ion channels and cure related diseases. However, bionic potassium ion channels have not been introduced into living cells to regulate cell function. One of the biggest challenges is that when the bionic channel fuses with the cell, it is difficult to control the inserting angle of the bionic potassium channel to ensure its penetration of the entire cell membrane. In nature, the extracellular vesicles can fuse with living cells with a completely preserved structure of vesicle protein. Inspired by this, we developed a vesicle fusion-based bionic porin (VFBP), which integrates bionic potassium ion channels into cardiomyocytes to replace damaged potassium ion channels. Theoretical and experimental results show that the inserted bionic ion channels have a potassium ion transport rate comparable to that of natural ion channels, which can restore the potassium ion outflow in cardiomyocytes and repair the abnormal action potential and excitation-contraction coupling of cardiomyocytes. Therefore, the bionic potassium ion channel system based on membrane fusion is expected to become the research object in many fields such as ultrafast ion transport, transmembrane delivery, and channelopathies treatment.

7.
J Am Chem Soc ; 146(1): 319-329, 2024 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-38129955

RESUMO

Tumor invasion and metastasis are the main causes of tumor progression and are the leading causes of death among cancer patients. In the present study, we propose a strategy to regulate cellular signaling with a tumor metastasis-relevant cytoskeleton-associated protein 4 (CKAP4) specific aptamer for the achievement of tumor metastasis inhibition. The designed aptamer could specifically bind to CKAP4 in the cell membranes and cytoplasm to block the internalization and recycling of α5ß1 integrin, resulting in the disruption of the fibronectin-dependent cell adhesion and the weakening of the cell traction force. Moreover, the aptamer is able to impede the interaction between CKAP4 and Dickkopf1 (DKK1) to further block the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) signaling pathway, which subsequently reduces AKT phosphorylation and inhibits the reorganization of the actin cytoskeleton in cell migration. The synergetic function of the designed aptamer in inhibiting cancer cell adhesion and blocking the PI3K signaling pathway enables efficient tumor cell metastasis suppression. The aptamer with specific targeting ability in regulating cellular signaling paves the way for cancer treatment and further provides a guiding ideology for inhibiting tumor metastasis.


Assuntos
Neoplasias , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular Tumoral , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Membrana Celular/metabolismo , Movimento Celular , Neoplasias/metabolismo
8.
J Hepatol ; 80(6): 858-867, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38336347

RESUMO

BACKGROUND & AIMS: HBV expresses more than 10 spliced RNAs from the viral pregenomic RNA, but their functions remain elusive and controversial. To address the function of HBV spliced RNAs, we generated splicing-deficient HBV mutants and conducted experiments to assess the impact of these mutants on HBV infection. METHODS: HepG2-NTCP cells, human hepatocyte chimeric FRG mice (hu-FRG mice), and serum from patients with chronic hepatitis B were used for experiments on HBV infection. Additionally, SHifter assays and cryo-electron microscopy were performed. RESULTS: We found the infectivity of splicing-deficient HBV was decreased 100-1,000-fold compared with that of wild-type HBV in hu-FRG mice. Another mutant, A487C, which loses the most abundant spliced RNA (SP1), also exhibits severely impaired infectivity. SP1 hypothetically encodes a novel protein HBcSP1 (HBc-Cys) that lacks the C-terminal cysteine from full-length HBc. In the SHifter assay, HBcSP1 was detected in wild-type viral particles at a ratio of about 20-100% vs. conventional HBc, as well as in the serum of patients with chronic hepatitis B, but not in A487C particles. When infection was conducted with a shorter incubation time of 4-8 h at lower PEG concentrations in HepG2-NTCP cells, the entry of the A487C mutant was significantly slower. SP1 cDNA complementation of the A487C mutant succeeded in rescuing its infectivity in hu-FRG mice and HepG2-NTCP cells. Moreover, cryo-electron microscopy revealed a disulfide bond between HBc cysteine 183 and 48 in the HBc intradimer of the A487C capsid, leading to a locked conformation that disfavored viral entry in contrast to the wild-type capsid. CONCLUSIONS: Prior studies unveiled the potential integration of the HBc-Cys protein into the HBV capsid. We confirmed the proposal and validated its identity and function during infection. IMPACT AND IMPLICATIONS: HBV SP1 RNA encodes a novel HBc protein (HBcSP1) that lacks the C-terminal cysteine from conventional HBc (HBc-Cys). HBcSP1 was detected in cell culture-derived HBV and confirmed in patients with chronic infection by both immunological and chemical modification assays at 10-50% of capsid. The splicing-deficient mutant HBV (A487C) impaired infectivity in human hepatocyte chimeric mice and viral entry in the HepG2-NTCP cell line. Furthermore, these deficiencies of the splicing-deficient mutant could be rescued by complementation with the SP1-encoded protein HBcSP1. We confirmed and validated the identity and function of HBcSP1 during infection, building on the current model of HBV particles.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Humanos , Animais , Vírus da Hepatite B/genética , Camundongos , Células Hep G2 , Hepatite B Crônica/virologia , Splicing de RNA , Mutação , RNA Viral/genética , RNA Viral/metabolismo , Microscopia Crioeletrônica
9.
J Hepatol ; 80(5): 714-729, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38336348

RESUMO

BACKGROUND & AIMS: Mechanisms behind the impaired response of antigen-specific B cells to therapeutic vaccination in chronic hepatitis B virus (HBV) infection remain unclear. The development of vaccines or strategies to overcome this obstacle is vital for advancing the management of chronic hepatitis B. METHODS: A mouse model, denominated as E6F6-B, was engineered to feature a knock-in of a B-cell receptor (BCR) that specifically recognizes HBsAg. This model served as a valuable tool for investigating the temporal and spatial dynamics of humoral responses following therapeutic vaccination under continuous antigen exposure. Using a suite of immunological techniques, we elucidated the differentiation trajectory of HBsAg-specific B cells post-therapeutic vaccination in HBV carrier mice. RESULTS: Utilizing the E6F6-B transfer model, we observed a marked decline in antibody-secreting cells 2 weeks after vaccination. A dysfunctional and atypical pre-plasma cell population (BLIMP-1+ IRF4+ CD40- CD138- BCMA-) emerged, manifested by sustained BCR signaling. By deploying an antibody to purge persistent HBsAg, we effectively prompted the therapeutic vaccine to provoke conventional plasma cell differentiation. This resulted in an enhanced anti-HBs antibody response and facilitated HBsAg clearance. CONCLUSIONS: Sustained high levels of HBsAg limit the ability of therapeutic hepatitis B vaccines to induce the canonical plasma cell differentiation necessary for anti-HBs antibody production. Employing a strategy combining antibodies with vaccines can surmount this altered humoral response associated with atypical pre-plasma cells, leading to improved therapeutic efficacy in HBV carrier mice. IMPACT AND IMPLICATIONS: Therapeutic vaccines aimed at combatting HBV encounter suboptimal humoral responses in clinical settings, and the mechanisms impeding their effectiveness have remained obscure. Our research, utilizing the innovative E6F6-B mouse transfer model, reveals that the persistence of HBsAg can lead to the emergence of an atypical pre-plasma cell population, which proves to be relevant to the potency of therapeutic HBV vaccines. Targeting the aberrant differentiation process of these atypical pre-plasma cells stands out as a critical strategy to amplify the humoral response elicited by HBV therapeutic vaccines in carrier mouse models. This discovery suggests a compelling avenue for further study in the context of human chronic hepatitis B. Encouragingly, our findings indicate that synergistic therapy combining HBV-specific antibodies with vaccines offers a promising approach that could significantly advance the pursuit of a functional cure for HBV.


Assuntos
Hepatite B Crônica , Hepatite B , Camundongos , Humanos , Animais , Antígenos de Superfície da Hepatite B , Vírus da Hepatite B , Vacinas contra Hepatite B/uso terapêutico , Anticorpos Anti-Hepatite B , Diferenciação Celular , Hepatite B/prevenção & controle , Hepatite B/tratamento farmacológico
10.
Biochem Biophys Res Commun ; 722: 150156, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-38797155

RESUMO

Osteosarcoma, considered as the primary cause of malignant bone tumors in children, necessitates novel therapeutic strategies to enhance overall survival rates. KAT7, a histone acetyltransferase, exerts pivotal functions in gene transcription and immune modulation. In light of this, our study identified a significant upregulation of KAT7 in the mRNA and protein levels in human osteosarcoma, boosting cell proliferation in vivo and in vitro. In addition, KAT7-mediated H3K14ac activation induced MMP14 transcription, leading to increased expression and facilitation of osteosarcoma cell metastasis. Subsequent bioinformatics analyses highlighted a correlation between KAT7 and adaptive immune responses, indicating CCL3 as a downstream target of KAT7. Mechanistically, STAT1 was found to transcriptionally upregulate CCL3 expression. Furthermore, overexpression of KAT7 suppressed CCL3 secretions, whereas knockdown of KAT7 enhanced its release. Overall, these findings underscore the oncogenic role of KAT7 in regulating immune responses for osteosarcoma treatment.


Assuntos
Neoplasias Ósseas , Quimiocina CCL3 , Regulação Neoplásica da Expressão Gênica , Histona Acetiltransferases , Osteossarcoma , Fator de Transcrição STAT1 , Transdução de Sinais , Animais , Humanos , Camundongos , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Quimiocina CCL3/metabolismo , Quimiocina CCL3/genética , Histona Acetiltransferases/metabolismo , Histona Acetiltransferases/genética , Camundongos Nus , Osteossarcoma/genética , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Fator de Transcrição STAT1/metabolismo , Fator de Transcrição STAT1/genética
11.
J Virol ; 97(2): e0168422, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36651747

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant is becoming a dominant circulator and has several mutations in the spike glycoprotein, which may cause shifts of immunogenicity, so as to result in immune escape and breakthrough infection among the already infected or vaccinated populations. It is unclear whether infection with Omicron could generate adequate cross-variant protection. To investigate this possibility, we used Syrian hamsters as an animal model for infection of SARS-CoV-2. The serum from Omicron BA.1 variant-infected hamsters showed a significantly lower neutralization effect against infection of the same or different SARS-CoV-2 variants than the serum from Beta variant-infected hamsters. Furthermore, the serum from Omicron BA.1 variant-infected hamsters were insufficient to protect against rechallenge of SARS-CoV-2 Prototype, Beta and Delta variants and itself. Importantly, we found that rechallenge with different SARS-CoV-2 lineages elevated cross-variant serum neutralization titers. Overall, our findings indicate a weakened immunogenicity feature of Omicron BA.1 variant that can be overcome by rechallenge of a different SARS-CoV-2 lineages. Our results may lead to a new guideline in generation and use of the vaccinations to combat the pandemic of SARS-CoV-2 Omicron variant and possible new variants. IMPORTANCE The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant causes breakthrough infections among convalescent patients and vaccinated populations. However, Omicron does not generate robust cross-protective responses. Here, we investigate whether heterologous SARS-CoV-2 challenge is able to enhance antibody response in a sensitive animal model, namely, Syrian hamster. Of note, a heterologous challenge of Beta and Omicron BA.1 variant significantly broadens the breadth of SARS-CoV-2 neutralizing responses against the prototype, Beta, Delta, and Omicron BA.1 variants. Our findings confirm that vaccination strategy with heterologous antigens might be a good option to protect against the evolving SARS-CoV-2.


Assuntos
COVID-19 , SARS-CoV-2 , Animais , Cricetinae , Anticorpos Neutralizantes , Anticorpos Antivirais , Antígenos Heterófilos/imunologia , Infecções Irruptivas , COVID-19/prevenção & controle , Mesocricetus , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Imunogenicidade da Vacina
12.
J Virol ; 97(11): e0113723, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37855619

RESUMO

IMPORTANCE: The ongoing COVID-19 pandemic has been characterized by the emergence of new SARS-CoV-2 variants including the highly transmissible Omicron XBB sublineages, which have shown significant resistance to neutralizing antibodies (nAbs). This resistance has led to decreased vaccine effectiveness and therefore result in breakthrough infections and reinfections, which continuously threaten public health. To date, almost all available therapeutic nAbs, including those authorized under Emergency Use Authorization nAbs that were previously clinically useful against early strains, have recently been found to be ineffective against newly emerging variants. In this study, we provide a comprehensive structural basis about how the Class 3 nAbs, including 1G11 in this study and noted LY-CoV1404, are evaded by the newly emerged SARS-CoV-2 variants.


Assuntos
Anticorpos Neutralizantes , COVID-19 , Pandemias , Humanos , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais , Infecções Irruptivas , COVID-19/imunologia , COVID-19/virologia
13.
J Med Virol ; 96(4): e29568, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38549430

RESUMO

The global incidence rate of kidney cancer (KC) has been steadily increasing over the past 30 years. With the aging global population, kidney cancer has become an escalating concern that necessitates vigilant surveillance. Nowadays, surgical intervention remains the optimal therapeutic approach for kidney cancer, while the availability of efficacious treatments for advanced tumors remains limited. Oncolytic viruses, an emerging form of immunotherapy, have demonstrated encouraging anti-neoplastic properties and are progressively garnering public acceptance. However, research on oncolytic viruses in kidney cancer is relatively limited. Furthermore, given the high complexity and heterogeneity of kidney cancer, it is crucial to identify an optimal oncolytic virus agent that is better suited for its treatment. The present study investigates the oncolytic activity of the Pseudorabies virus live attenuated vaccine (PRV-LAV) against KC. The findings clearly demonstrate that PRV-LAV exhibits robust oncolytic activity targeting KC cell lines. Furthermore, the therapeutic efficacy of PRV-LAV was confirmed in both a subcutaneous tumor-bearing nude mouse model and a syngeneic mouse model of KC. Combined RNA-seq analysis and flow cytometry revealed that PRV-LAV treatment substantially enhances the infiltration of a diverse range of lymphocytes, including T cells, B cells, macrophages, and NK cells. Additionally, PRV-LAV treatment enhances T cell activation and exerts antitumor effects. Importantly, the combination of PRV-LAV with anti-PD-1 antibodies, an approved drug for KC treatment, synergistically enhances the efficacy against KC. Overall, the discovery of PRV-LAV as an effective oncolytic virus holds significant importance for improving the treatment efficacy and survival rates of KC patients.


Assuntos
Vacinas Anticâncer , Herpesvirus Suídeo 1 , Inibidores de Checkpoint Imunológico , Neoplasias Renais , Vírus Oncolíticos , Animais , Humanos , Camundongos , Linhagem Celular Tumoral , Herpesvirus Suídeo 1/genética , Neoplasias Renais/terapia , Vírus Oncolíticos/genética , Receptor de Morte Celular Programada 1 , Microambiente Tumoral , Vacinas Atenuadas , Vacinas Anticâncer/uso terapêutico , Inibidores de Checkpoint Imunológico/uso terapêutico
14.
Opt Express ; 32(3): 3031-3045, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297535

RESUMO

We propose and design a multi-stage cascaded scanning laser ophthalmoscope (SLO) for ultra-wide field (UWF), which uses conicoid mirrors, constructed by conjugation of pupil plane. The vergence uniformity and the angular magnification of a cascaded conicoid mirrors (CCM) system are analyzed recursively and optimized preliminarily to achieve high quality imaging with UWF, and the optimal system with the model eye are obtained by simulation and optimization. Two-stage and three-stage cascaded systems are designed with this method, and the formulas of beam vergence and angular magnification are obtained by theoretical derivation. As compared to the two-stage CCM system, the proposed three-stage cascaded UWF SLO has superior performance in imaging quality. Its average RMS radius of spot diagram is calculated to be 26.372 µm, close to the diffractive limit resolution. The image resolution of human retina can be up to 30 µm with 135° FOV in theory. The three-stage cascaded SLO is more suitable for UWF fundus imaging. This study will be helpful for early screening and accurate diagnosis of various diseases in the peripheral retina.


Assuntos
Oftalmoscópios , Retina , Humanos , Oftalmoscopia/métodos , Fundo de Olho , Retina/diagnóstico por imagem , Lasers
15.
Pediatr Res ; 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760472

RESUMO

BACKGROUND: The risk factors for central venous access device-related thrombosis (CRT) in children are not fully understood. We used evidence-based medicine to find the risk factors for CRT by pooling current studies reporting risk factors of CRT, aiming to guide clinical diagnosis and treatment. METHODS: A systematic search of PubMed, Web of Science, Embase, Cochrane Library, Scopus, CNKI, Sinomed, and Wanfang databases was conducted. RevMan 5.4 was employed for data analysis. RESULTS: The review included 47 studies evaluating 262,587 children with CVAD placement. Qualitative synthesis and quantitative meta-analysis identified D-dimer, location of insertion, type of catheter, number of lumens, catheter indwelling time, and central line-associated bloodstream infection as the most critical risk factors for CRT. Primarily due to observational design, the quality of evidence was regarded as low certainty for these risk factors according to the GRADE approach. CONCLUSION: Because fewer high-quality studies are available, larger sample sizes and well-designed prospective studies are still needed to clarify the risk factors affecting CRT. In the future, developing pediatric-specific CRT risk assessment tools is important. Appropriate stratified preventive strategies for CRT according to risk assessment level will help improve clinical efficiency, avoid the occurrence of CRT, and alleviate unnecessary suffering of children. IMPACT: This is the latest systematic review of risk factors and incidence of CRT in children. A total of 47 studies involving 262,587 patients were included in our meta-analysis, according to which the pooled prevalence of CRT was 9.1%. This study identified several of the most critical risk factors affecting CRT in children, including D-dimer, insertion location, type of catheter, number of lumens, catheter indwelling time, and central line-associated bloodstream infection (CLABSI).

16.
BMC Public Health ; 24(1): 163, 2024 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212753

RESUMO

BACKGROUND: China has the third-largest burden of tuberculosis (TB) cases in the world with great challenges towards ending TB. Primary health care (PHC) sectors play a critical role in TB prevention and control in communities under the Chinese integrated TB control model. However, there is a lack of comprehensive review of research evidence on TB control in PHC sectors under the integrated TB control model in China. METHODS: This review was conducted following the PRISMA guidelines. Articles published from 2012 to January 2022 were searched from four international and three Chinese databases. Studies conducted inside mainland China and relevant with TB control service in PHC sectors under the integrated model were included. After study selection, data extraction, and quality assessment, the meta-analysis was performed with RevMan using a random-effect model.When I2 was more than 50%, subgroup analysis was performed to explore possible reasons for heterogeneity. We also conducted a post hoc sensitivity analysis for outcomes after meta-analysis by exclusion of studies with a high risk of bias or classified as low quality. RESULTS: Forty-three studies from 16 provinces/municipalities in China were included in this review, and most studies included were of medium quality. PHC sectors in East China delivered TB control service better overall than that in West China, especially in tracing of patients and TB case management (TCM). In meta-analyses, both the pooled arrival rate of tracing and pooled TCM rate in East China were higher than those in West China. TB patients had a low degree of willingness to receive TCM provided by healthcare workers in PHC sectors nationwide, especially among migrant TB patients. There were 9 studies reporting factors related to TB control service in PHC sectors, 6 (2 in East and 4 in West China) of which indentified several characteristics of patients as associated factors. The context of PHC sectors was demonstrated to influence delivery of TB control service in PHC sectors in 5 studies (3 in East, 1 in Middle and 1 in West China). Most studies on strategies to promoting TB control services in PHC sectors were conducted in East China and some of these studies identified several online and offline interventions and strategies improving patients' treatment compliance [pooled OR (95% CI): 7.81 (3.08, 19.19] and awareness of TB [pooled OR (95% CI): 6.86 (2.16, 21.72)]. CONCLUSION: It is of urgent need to improve TB control in PHC sector in China, particularly in West China. Formative and implementation research with rigorous design are necessary to develop comprehensive, context-specific, and patient-centered TB control strategies to promote ending TB in China.


Assuntos
Setor de Assistência à Saúde , Tuberculose , Humanos , Tuberculose/epidemiologia , Tuberculose/prevenção & controle , Cooperação do Paciente , China/epidemiologia
17.
Proc Natl Acad Sci U S A ; 118(23)2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34074746

RESUMO

The construction and maturation of the postsynaptic apparatus are crucial for synapse and dendrite development. The fundamental mechanisms underlying these processes are most often studied in glutamatergic central synapses in vertebrates. Whether the same principles apply to excitatory cholinergic synapses, such as those found in the insect central nervous system, is not known. To address this question, we investigated a group of projection neurons in the Drosophila larval visual system, the ventral lateral neurons (LNvs), and identified nAchRα1 (Dα1) and nAchRα6 (Dα6) as the main functional nicotinic acetylcholine receptor (nAchR) subunits in the larval LNvs. Using morphological analyses and calcium imaging studies, we demonstrated critical roles of these two subunits in supporting dendrite morphogenesis and synaptic transmission. Furthermore, our RNA sequencing analyses and endogenous tagging approach identified distinct transcriptional controls over the two subunits in the LNvs, which led to the up-regulation of Dα1 and down-regulation of Dα6 during larval development as well as to an activity-dependent suppression of Dα1 Additional functional analyses of synapse formation and dendrite dynamics further revealed a close association between the temporal regulation of individual nAchR subunits and their sequential requirements during the cholinergic synapse maturation. Together, our findings support transcriptional control of nAchR subunits as a core element of developmental and activity-dependent regulation of central cholinergic synapses.


Assuntos
Neurônios Colinérgicos/metabolismo , Dendritos/metabolismo , Proteínas de Drosophila/biossíntese , Morfogênese , Receptores Nicotínicos/biossíntese , Sinapses/metabolismo , Transmissão Sináptica , Animais , Drosophila melanogaster , Larva/metabolismo
18.
Ecotoxicol Environ Saf ; 277: 116370, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38663198

RESUMO

Total dissolved gas (TDG) supersaturation caused by flood discharge water poses a threat to vital activities such as migration, foraging, and evasion in fish species upstream of the Yangtze River, which may impair the ability of fish to pass through fishways during the migration period, causing poor utilization of fishways. Previous studies have shown that TDG supersaturation reduces the critical and burst swimming abilities of fish, suggesting potential adverse effects on swimming performance. However, studies focusing on the impact of TDG on fish swimming behavior in experimental vertical-slot fishways remain scarce. Therefore, in this study, silver carp (Hypophthalmichthys molitrix) and ya-fish (Schizothorax prenanti) were used as the study species, and comparative passage experiments were carried out in an experimental vertical slot fishway to systematically analyze the effects of TDG supersaturation on their passage behavior. The passage success of the silver carp was 57%, 39%, 26%, and 27% at TDG levels of 100%, 110%, 120%, and 130%, respectively. Passage success of ya-fish was 73%, 37%, 31%, and 35% at TDG concentrations of 100%, 110%, 120%, and 130%, respectively. The passage time for both species increased significantly with increasing TDG levels. Furthermore, the passage routes of silver carp changed significantly compared to the control group, whereas the passage routes of ya-fish changed insignificantly. High levels of TDG supersaturation (≥120%) also contributed to a higher mortality rate of ya-fish passing through the vertical slot fishway. The research results provide valuable data on the influence of TDG supersaturation on fish movement behavior responses in experimental vertical slot fishways, offering a reference for the design of fishways and the formulation of reservoir operation schemes.


Assuntos
Carpas , Natação , Animais , Carpas/fisiologia , Rios/química , Poluentes Químicos da Água/toxicidade , Gases , China , Comportamento Animal/efeitos dos fármacos , Migração Animal/efeitos dos fármacos , Cyprinidae/fisiologia
19.
Sensors (Basel) ; 24(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38931808

RESUMO

To improve the accuracy and robustness of autonomous vehicle localization in a complex environment, this paper proposes a multi-source fusion localization method that integrates GPS, laser SLAM, and an odometer model. Firstly, fuzzy rules are constructed to accurately analyze the in-vehicle localization deviation and confidence factor to improve the initial fusion localization accuracy. Then, an odometer model for obtaining the projected localization trajectory is constructed. Considering the high accuracy of the odometer's projected trajectory within a short distance, we used the shape of the projected localization trajectory to inhibit the initial fusion localization noise and used trajectory matching to obtain an accurate localization. Finally, the Dual-LSTM network is constructed to predict the localization and build an electronic fence to guarantee the safety of the vehicle while also guaranteeing the updating of short-distance localization information of the vehicle when the above-mentioned fusion localization is unreliable. Under the limited arithmetic condition of the vehicle platform, accurate and reliable localization is realized in a complex environment. The proposed method was verified by long-time operation on the real vehicle platform, and compared with the EKF fusion localization method, the average root mean square error of localization was reduced by 66%, reaching centimeter-level localization accuracy.

20.
J Prosthet Dent ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38604906

RESUMO

With the development of digital dental technologies, a complete digital workflow without using physical casts has become possible. However, for certain clinical and dental laboratory procedures, especially in complex rehabilitation treatments, physically mounted casts in an ideal location in a mechanical articulator are still necessary for treatment planning and restoration fabrication. This technique report describes a digital approach to fabricating a custom transfer plate to cross mount intraoral scan casts from a virtual articulator to the corresponding mechanical articulator. This technique eliminates the need for conventional physical facebow transfer processes and offers a straightforward approach to integrating virtual procedures with analog workflows.

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