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1.
Leuk Res ; 142: 107507, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38692191

RESUMO

PURPOSE: To assess the real-world efficacy and safety of flumatinib as first-line and post-line treatments for chronic myeloid leukemia in the chronic phase (CML-CP). RESULTS: Among 141 patients receiving flumatinib as first-line and post-line treatment, the 12-month major molecular response (MMR) rates were 69.4% and 67.6%, respectively. The median time to response was 6 and 10.5 months, respectively. In post-line treatment, the early molecular response (EMR) of flumatinib as second-line is significantly superior to that of third-line treatment (3-month EMR rate: 79.2% vs. 39.3%, P<0.001; 3-month MMR rate: 45.8% vs. 21.4%, P=0.033). Contrastively, patients who switched to flumatinib due to intolerance had significantly higher MMR rates at 3, 6, and 12 months compared to patients who switched due to inadequate response (60.6% vs. 24.2%, P=0.003; 66.7% vs. 36.0%, P=0.027; 84.2% vs. 50.0%, P=0.038). Premature drug discontinuation was observed in 28.4% of the patients. Grades 3-4 hematologic adverse events (AEs) were identified as independent risk factors for premature drug discontinuation. Patients who discontinued treatment and those who previously received only imatinib therapy had a poorer molecular response and failure-free survival. CONCLUSIONS: Flumatinib demonstrates favorable efficacy and safety. Treatment discontinuation can result in a poorer molecular response and long-term prognosis.

2.
Angew Chem Int Ed Engl ; : e202403258, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38721770

RESUMO

BRD4 protein plays a pivotal role in cell cycle regulation and differentiation. Disrupting the activity of BRD4 has emerged as a promising strategy for inhibiting the growth and proliferation of cancer cells. Herein, we introduced a BRD4-targeting photothermal agent for controlled protein degradation, aiming to enhance low-temperature photothermal therapy (PTT) for cancer treatment. By incorporating a BRD4 protein inhibitor into a cyanine dye scaffold, the photothermal agent specifically bond to the bromodomain of BRD4. Upon low power density laser irradiation, the agent induced protein degradation, directly destroying the BRD4 structure and inhibiting its transcriptional regulatory function. This strategy not only prolonged the retention time of the photothermal agent in cancer cells but also confined the targeted protein degradation process solely to the tumor tissue, minimizing side effects on normal tissues through the aid of exogenous signals. This work established a simple and feasible platform for future PTT agent design in clinical cancer treatment.

4.
Gland Surg ; 13(3): 325-339, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38601284

RESUMO

Background: Breast cancer (BC) is one of the most common malignancies worldwide, and its development is affected in various ways by the tumor microenvironment (TME). Tumor-derived mesenchymal progenitor cells (MPCs), as the most important components of the TME, participate in the proliferation and metastasis of BC in several ways. In this study, we aimed to characterize the genes associated with tumor-derived MPCs and determine their effects on BC cells. Methods: Tumor-derived MPCs and normal breast tissue-derived mesenchymal stem cells (MSCs) were isolated from tissues specimens of patients with BC. We conducted culture and passage, phenotype identification, proliferation and migration detection, inflammatory factor release detection, and other experiments on isolated MPCs from tumors and MSCs from normal breast tissues. Three paired tumor-derived MPCs and normal breast tissue-derived MSCs were then subjected to transcriptome analysis to determine the expression profiles of the relevant genes, and quantitative real-time polymerase chain reaction (qRT-PCR) was used to further confirm gene expression. Subsequently, the overexpression plasmids were transfected into tumor-derived MPCs, and the expression of various inflammatory factors of tumor-derived MPCs and their proliferation were characterized with a cell viability test reagent (Cell Counting Kit 8). Subsequently, the transfected tumor-derived MPCs were cocultured with BC cells using a conditioned medium coculture method to clarify the role of tumor-derived MSCs in BC. Results: Tumor-derived MPCs expressed stem cell characteristics including CD105, CD90, and CD73 and exhibited adipogenic and osteogenic differentiation in vitro. The proliferation of tumor-derived MPCs was significantly lower than that of normal breast tissue-derived MSCs, and the invasive metastatic ability was comparable; however, MPCs were found to release inflammatory factors such as interleukin 6 (IL-6) and transforming growth factor ß (TGF-ß). Transcriptome analysis showed that stomatin (STOM), collagen and calcium binding EGF domains 1 (CCBE1), and laminin subunit alpha 5 (LAMA5) were significantly upregulated in tumor-derived MPCs. Among them, STOM was highly expressed in tumor-derived MPCs, which mediated the slow proliferation of MPCs and promoted the proliferation of BC cells. Conclusions: STOM, CCBE1, and LAMA5 were highly expressed in tumor-derived MPCs, with STOM being found to retard the proliferation of MPCs but promote the proliferation of BC cells. There findings present new possibilities in targeted microenvironmental therapy for BC.

5.
Neuroendocrinology ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38583420

RESUMO

INTRODUCTION: Progestin, commonly used in oral contraception and preventing preterm birth, elicits various off-target side effects on brain and gastrointestinal (GI) functions, yet the precise mechanisms remain elusive. This study aims to probe progestin's impact on GI function and anxiety-like behaviors in female mice. METHODS: Colon stem cells were utilized to explore the mechanism underlying progestin 17-hydroxyprogesterone caproate (17-OHPC)-mediated suppression of claudin-1 (CLDN1), crucial for epithelial integrity. Chromatin immunoprecipitation and luciferase assays identified potential progestin-response elements on the CLDN1 promoter, with subsequent assessment of oxidative stress and pro-inflammatory cytokine release. Manipulation of vitamin D receptor (VDR) or estrogen receptor ß (ERß) expression elucidated their roles in 17-OHPC-mediated effects. Intestine-specific VDR deficient mice were generated to evaluate 17-OHPC's impact on GI dysfunction and anxiety-like behaviors in female mice. Additionally, gene expression was analyzed in various brain regions, including the amygdala, hypothalamus, and hippocampus. RESULTS: Exposure to 17-OHPC suppressed CLDN1 expression via epigenetic modifications and VDR dissociation from the CLDN1 promoter. Furthermore, 17-OHPC intensified oxidative stress and proinflammatory cytokine release. VDR knockdown partly mimicked, while overexpression of either VDR or ERß partly restored 17-OHPC-mediated effects. Intestinal VDR deficiency partly mirrored 17-OHPC-induced GI dysfunction, with minimal impact on 17-OHPC-mediated anxiety-like behaviors. CONCLUSIONS: 17-OHPC suppresses CLDN1 expression through VDR, contributing to GI dysfunction in female mice, distinct from 17-OHPC-induced anxiety-like behaviors. This study reveals a new mechanism and potential negative impact of progestin exposure on the gastrointestinal tract, alongside inducing anxiety-like behaviors in female mice.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38551435

RESUMO

Objective: To assess the effectiveness of perioperative nursing interventions in improving outcomes and satisfaction for patients undergoing laparoscopic surgery for ovarian endometriosis. Methods: From July 2021 to September 2022, 80 patients with endometriosis underwent laparoscopic surgery at Shijiazhuang Fourth Hospital and were randomly assigned to the conventional (n=40) and experimental (n=40) groups. During the perioperative period, patients in the conventional group received standard nursing interventions, while patients in the experimental group received comprehensive nursing interventions. The two groups were compared in terms of postoperative clinical indicators, self-rated anxiety scale (SAS) and self-rated depression scale (SDS) scores, nursing compliance, complications, and nursing satisfaction. Results: comprehensive nursing resulted in better postoperative clinical indices (time to get out of bed, hospital stay) versus routine nursing (all P < .001). The comprehensive nursing led to significantly lower SAS and SDS scores versus routine nursing. The nursing compliance of the patients in the experimental group was significantly higher than that of the patients in the conventional group (P < .001). Comprehensive nursing was associated with a significantly lower incidence of complications versus routine nursing (P < .001). Comprehensive nursing contributed to significantly higher nursing satisfaction versus routine nursing (P < .001). Conclusion: Comprehensive perioperative nursing interventions for patients with ovarian endometriosis undergoing laparoscopic surgery considerably accelerate patient recovery and enhance nursing compliance, as well as minimize patient negative emotions and improve patient satisfaction with nursing.  The comprehensive approach addresses the specific needs of patients during the recovery period, minimizing postoperative complications, accelerating patient recovery, and improving overall quality of life. By integrating psychological support, tailored strategies for pain management, early mobilization, and prompt intervention for complications, this intervention sets a benchmark for holistic care in gynecological surgery.

8.
Adv Healthc Mater ; : e2303749, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483042

RESUMO

The Golgi apparatus (GA) is central in shuttling proteins from the endoplasmic reticulum to different cellular areas. Therefore, targeting the GA to precisely destroy its proteins through local heat could induce apoptosis, offering a potential avenue for effective cancer therapy. Herein, a GA-targeted photothermal agent based on protein anchoring is introduced for enhanced photothermal therapy of tumor through the modification of near-infrared molecular dye with maleimide derivative and benzene sulfonamide. The photothermal agent can actively target the GA and covalently anchor to its sulfhydryl proteins, thereby increasing its retention within the GA. Under laser irradiation, the heat generated by the photothermal agent efficiently disrupts sulfhydryl proteins in situ, leading to GA dysfunction and ultimately inducing cell apoptosis. In vivo experiments demonstrate that the photothermal agent can precisely treat tumors and significantly reduce side effects.

9.
Exp Hematol Oncol ; 13(1): 22, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38402232

RESUMO

Cellular immunotherapy, particularly CAR-T cells, has shown potential in the improvement of outcomes in patients with refractory and recurrent malignancies of the blood. However, achieving sustainable long-term complete remission for blood cancer remains a challenge, with resistance and relapse being expected outcomes for many patients. Although many studies have attempted to clarify the mechanisms of CAR-T cell therapy failure, the mechanism remains unclear. In this article, we discuss and describe the current state of knowledge regarding these factors, which include elements that influence the CAR-T cell, cancer cells as a whole, and the microenvironment surrounding the tumor. In addition, we propose prospective approaches to overcome these obstacles in an effort to decrease recurrence rates and extend patient survival subsequent to CAR-T cell therapy.

10.
J Enzyme Inhib Med Chem ; 39(1): 2315227, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38421003

RESUMO

Pterostilbene (PST) is a naturally derived stilbene compound in grapes, blueberries, and other fruits. It is also a natural dietary compound with a wide range of biological activities such as antioxidant, anti-inflammatory, antitumor, and so on. Structural modifications based on the chemical scaffold of the pterostilbene skeleton are of great importance for drug discovery. In this study, pterostilbene skeletons were used to design novel anti-inflammatory compounds with high activity and low toxicity. A total of 30 new were found and synthesised, and their anti-inflammatory activity and safety were screened. Among them, compound E2 was the most active (against NO: IC50 = 0.7 µM) than celecoxib. Further studies showed that compound E2 exerted anti-inflammatory activity by blocking LPS-induced NF-κB/MAPK signalling pathway activation. In vivo experiments revealed that compound E2 had a good alleviating effect on acute colitis in mice. In conclusion, compound E2 may be a promising anti-inflammatory lead compound.


Assuntos
Transdução de Sinais , Estilbenos , Camundongos , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Estilbenos/farmacologia , NF-kappa B/metabolismo , Lipopolissacarídeos/farmacologia
11.
Sci Rep ; 14(1): 2187, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38273011

RESUMO

Bladder cancer is a common malignant tumor, and patients who have undergone radical cystectomy and urinary diversion require a lifelong abdominal stoma. This greatly affects their physiological, psychological, and social well-being. However, there is currently a lack of a self-assessment outcome scale specifically designed for bladder cancer patients with abdominal stomas. Therefore, we developed and validated a self-assessment outcome scale (PROS-BCAS) for Chinese bladder cancer patients with abdominal stomas. The scale was initially developed through literature research and expert consultation, and it comprised four dimensions: physiological, psychological, social, and treatment, with a total of 66 items. After item analysis, 44 items were retained. We collected scale data from 382 patients to examine its validity and reliability. The results showed that the PROS-BCAS scale had good content validity (S-CVI/Ave = 0.992), construct validity (KMO > 0.6), and discriminant validity (correlation coefficient 0.404-0.870). The Cronbach's alpha coefficients (0.801-0.954), test-retest reliability (0.778-0.956), and split-half reliability (0.896-0.977) all demonstrated good internal consistency for each dimension and the overall scale. The study demonstrated that the PROS-BCAS scale is a reliable and valid tool for accurately assessing the health-related quality of life of bladder cancer patients with abdominal stomas, providing reference for developing individualized clinical care plans.


Assuntos
Qualidade de Vida , Neoplasias da Bexiga Urinária , Humanos , Qualidade de Vida/psicologia , Reprodutibilidade dos Testes , Psicometria/métodos , Inquéritos e Questionários , Neoplasias da Bexiga Urinária/diagnóstico , Neoplasias da Bexiga Urinária/cirurgia , China
13.
Food Chem X ; 20: 101006, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-38046180

RESUMO

This study investigated the modification of myofibrillar protein (MP) from the razor clam through phosphorylation by using various phosphate salts, namely, sodium tripolyphosphate (STPP), sodium trimetaphosphate (STMP), sodium polyphosphate (STTP) and sodium pyrophosphate (TSPP), and their mechanisms of action for functional and gelling properties. Fourier transform infrared spectrometry (FTIR) showed that MP introduced phosphate groups during phosphorylation; these phosphates changed the secondary structure. Moreover, MP after phosphorylation led to an increase in solubility, which was more evident in the case of TSPP phosphorylation, leading to the improvement of gel properties. Therefore, TSPP was the phosphate with the best gel properties in the modification of MP, showing the highest phosphorus content, which resulted in better gelling properties owing to its relatively shorter chains. These results showed that phosphate was able to improve protein cross-linking through ion interactions and electrostatic interactions, which ultimately improved the gelling properties of the razor clam protein.

14.
Front Oncol ; 13: 1296456, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38098505

RESUMO

Mitochondrial heat shock protein 90 (mtHsp90), including Tumor necrosis factor receptor-associated protein 1 (TRAP1) and Hsp90 translocated from cytoplasm, modulating cellular metabolism and signaling pathways by altering the conformation, activity, and stability of numerous client proteins, and is highly expressed in tumors. mtHsp90 inhibition results in the destabilization and eventual degradation of its client proteins, leading to interference with various tumor-related pathways and efficient control of cancer cell development. Among these compounds, gamitrinib, a specific mtHsp90 inhibitor, has demonstrated its safety and efficacy in several preclinical investigations and is currently undergoing evaluation in clinical trials. This review aims to provide a comprehensive overview of the present knowledge pertaining to mtHsp90, encompassing its structure and function. Moreover, our main emphasis is on the development of mtHsp90 inhibitors for various cancer therapies, to present a thorough overview of the recent pre-clinical and clinical advancements in this field.

15.
Gland Surg ; 12(10): 1360-1374, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-38021193

RESUMO

Background: Cone-beam breast computed tomography (CBBCT) is a new breast imaging technique, however, CBBCT is not yet widely used, and its future application will depend on its diagnostic potential and application value. Therefore, it is of great clinical significance to systematically review and analyze the diagnostic accuracy of CBBCT for breast cancer detection in existing studies and compare it with other traditional imaging methods for the diagnosis of breast lesions. Methods: We searched PubMed, Embase, Web of Science, and Chinese databases until August 2022 for relevant papers. Studies evaluating the diagnostic accuracy of CBBCT in women with suspected breast cancer were included. Each study's quality was evaluated using the Quality Assessment of Diagnostic Performance Studies-2 (QUADAS-2) instrument. Results: Eighteen studies with a total of 1,792 patients were included in the analysis. The overall pooled sensitivity and specificity of CBBCT in diagnosing breast cancer were 0.95 [95% confidence interval (CI): 0.91-0.97] and 0.72 (95% CI: 0.62-0.80), respectively. The area under the curve (AUC) for CBBCT was 0.92 (95% CI: 0.90-0.94). In a head-to-head comparison of CBBCT and digital mammography (DM), eight trials with 992 patients were included in the study, and the AUCs for CBBCT and DM were 0.94 (95% CI: 0.92-0.96) and 0.83 (95% CI: 0.80-0.83), respectively. In a head-to-head comparison of CBBCT and magnetic resonance imaging (MRI), four trials with 203 patients were included in the analysis; the AUC for CBBCT and MRI were 0.88 (95% CI: 0.85-0.91) and 0.96 (95% CI: 0.94-0.97), respectively. Conclusions: This meta-analysis of CBBCT test accuracy indicated encouraging diagnostic performance. In the summary of head-to-head comparative studies, there is a tendency for CBBCT to have greater diagnostic accuracy than DM, although its diagnostic performance is marginally inferior to that of MRI. However, the meta-analysis results were derived from studies with limited sample sizes. There is a need for more extensive research in this setting.

16.
J Chromatogr A ; 1711: 464448, 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37852047

RESUMO

Simultaneous determination of multiple biomarkers can improve the effectiveness and accuracy of cancer diagnosis. Cortisol, cortisone, and 4-methoxyphenylacetic acid (4-Me) are metabolic biomarker group with high specificity and sensitivity for the diagnosis of non-small cells lung cancer (NSCLC), and the development of their simultaneous determination method is desired. Herein, a simple, sensitive, and low-cost method involving pipette-tip solid-phase extraction (PT-SPE) using anion exchange adsorbent (MAX) coupled with liquid chromatography tandem mass spectrometry (LC-MS/MS) was developed for the simultaneous determination of three biomarkers (cortisol, cortisone, and 4-Me) in human urine. The sample (0.1 mL), adsorbent (1.5 mg) and organic reagent (3.5 mL) of MAX-PT-SPE are less consumed, and have the advantages of easy access to raw materials, simple assembly, convenient on-site instant extraction, low pollution, and low cost. The limits of detection of the three biomarkers were 0.006-0.024 ng mL-1, the recoveries of three spiked levels (2, 50, and 500 ng mL-1) were 91.0%-99.3%, with the relative standard deviations (RSDs) ≤ 5.9%. Finally, the MAX-PT-SPE-LC-MS/MS method achieved the quantitative analysis of cortisol, cortisone, and 4-Me in urine of different patients of NSCLC. This method is expected to be used in the non-invasive auxiliary diagnosis of NSCLC, and it provides a new strategy for multi-molecular diagnosis and multi-omics combined diagnosis.


Assuntos
Cortisona , Neoplasias Pulmonares , Humanos , Cromatografia Líquida , Espectrometria de Massas em Tandem , Hidrocortisona , Neoplasias Pulmonares/diagnóstico , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos
17.
Plant Physiol Biochem ; 203: 108076, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37832366

RESUMO

The MADS-box transcription factor APETELA1 (AP1) is crucially important for reproductive developmental processes. The function of AP1 and the classic LFY-AP1 interaction in woody plants are not widely known. Here, the OfAP1-a gene from the continuously flowering plant Osmanthus fragrans 'Sijigui' was characterized, and its roles in regulating flowering time, petal number robustness and floral organ identity were determined using overexpression in Arabidopsis thaliana and Nicotiana tabacum. The expression of OfAP1-a was significantly induced by low ambient temperature and was upregulated with the floral transition process. Ectopic expression OfAP1-a revealed its classic function in flowering and flower ABC models. The expression of OfAP1-a is inhibited by LEAFY (OfLFY) through direct promoter binding, as confirmed by yeast one-hybrid and dual luciferase assays. Arabidopsis plants overexpressing OfAP1-a exhibited accelerated flowering and altered floral organ identities. Moreover, OfAP1-a-overexpressing plants displayed variable petal numbers. Likewise, the overexpression of OfLFY in Arabidopsis and Nicotiana altered petal number robustness and inflorescence architecture, partially by regulating native AP1 in transformed plants. Furthermore, we performed RNA-seq analysis of transgenic Nicotiana plants. DEGs were identified by transcriptome analysis, and we found that the expression of several floral homeotic genes was altered in both OfAP1-a and OfLFY-overexpressing transgenic lines. Our results suggest that OfAP1-a may play important roles during floral transition and development in response to ambient temperature. OfAP1-a functions as a petal number modulator and may directly activate a subset of flowers to regulate floral organ formation. OfAP1-a and OfLFY mutually regulate the expression of each other and coregulate genes that might be involved in these phenotypes related to flowering. The results provide valuable data for understanding the function of the LFY-AP1 module in the reproductive process and shaping floral structures in woody plants.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Arabidopsis/metabolismo , Temperatura , Fatores de Transcrição/genética , Proteínas de Arabidopsis/genética , Fenótipo , Flores/metabolismo , Plantas Geneticamente Modificadas/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Domínio MADS/genética , Proteínas de Domínio MADS/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
18.
Biosens Bioelectron ; 239: 115584, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37619479

RESUMO

MicroRNAs (miRNAs) have emerged as important biomarkers in biomedicine and bioimaging due to their roles in various physiological and pathological processes. Real-time and in situ monitoring of dynamic fluctuation of miRNAs in living cells is crucial for understanding these processes. However, current miRNA imaging probes still have some limitations, including the lack of effective amplification methods for low abundance miRNAs bioanalysis and uncontrollable activation, leading to background signals and potential false-positive results. Therefore, researchers have been integrating activatable devices with miRNA amplification techniques to design stimuli-responsive nanoprobes for "on-demand" and precise imaging of miRNAs in living cells. In this review, we summarize recent advances of stimuli-responsive probes for the amplification-based imaging of miRNAs in living cells and discuss the future challenges and opportunities in this field, aiming to provide valuable insights for accurate disease diagnosis and monitoring.


Assuntos
Amplificação de Genes , Humanos , MicroRNAs/química , MicroRNAs/genética , MicroRNAs/metabolismo , Sobrevivência Celular , Trifosfato de Adenosina/metabolismo , Concentração de Íons de Hidrogênio
19.
Research (Wash D C) ; 6: 0215, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37614365

RESUMO

Solid tumor cells live in a highly dynamic mechanical microenvironment. How the extracellular-matrix-generated mechanotransduction regulates tumor cell development and differentiation remains an enigma. Here, we show that a low mechanical force generated from the soft matrix induces dedifferentiation of moderately stiff tumor cells to soft stem-cell-like cells. Mechanistically, integrin ß8 was identified to transduce mechano-signaling to trigger tumor cell dedifferentiation by recruiting RhoGDI1 to inactivate RhoA and subsequently Yes-associated protein (YAP). YAP inactivation relieved the inhibition of v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog G (MAFG), allowing MAFG to transactivate the stemness genes NANOG, SOX2, and NESTIN. Inactivation also restored ß8 expression, thereby forming a closed mechanical loop. Importantly, MAFG expression is correlated with worse prognosis. Our findings provide mechanical insights into the regulation of tumor cell dedifferentiation, which has therapeutic implications for exploring innovative strategies to attack malignancies.

20.
Sensors (Basel) ; 23(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37420608

RESUMO

Lightweight, high stability, and high-temperature adaptability are the primary considerations when designing the primary mirror of a micro/nano satellite remote sensing camera. In this paper, the optimized design and experimental verification of the large-aperture primary mirror of the space camera with a diameter of Φ610 mm is carried out. First, the design performance index of the primary mirror was determined according to the coaxial tri-reflective optical imaging system. Then, SiC, with excellent comprehensive performance, was selected as the primary mirror material. The initial structural parameters of the primary mirror were obtained using the traditional empirical design method. Due to the improvement of SiC material casting complex structure reflector technology level, the initial structure of the primary mirror was improved by integrating the flange with the primary mirror body design. The support force acts directly on the flange, changing the transmission path of the traditional back plate support force, and has the advantage that the primary mirror surface shape accuracy can be maintained for a long time when subjected to shock, vibration, and temperature changes. Then, a parametric optimization algorithm based on the mathematical method of compromise programming was used to optimize the design of the initial structural parameters of the improved primary mirror and the flexible hinge, and finite element simulation was conducted on the optimally designed primary mirror assembly. Simulation results show that the root mean square (RMS) surface error is less than λ/50 (λ = 632.8 nm) under gravity, 4 °C temperature rise, and 0.01 mm assembly error. The mass of the primary mirror is 8.66 kg. The maximum displacement of the primary mirror assembly is less than 10 µm, and the maximum inclination angle is less than 5″. The fundamental frequency is 203.74 Hz. Finally, after the primary mirror assembly was precision manufactured and assembled, the surface shape accuracy of the primary mirror was tested by ZYGO interferometer, and the test value was 0.02 λ. The vibration test of the primary mirror assembly was conducted at a fundamental frequency of 208.25 Hz. This simulation and experimental results show that the optimized design of the primary mirror assembly meets the design requirements of the space camera.


Assuntos
Algoritmos , Placas Ósseas , Biópsia , Comércio , Simulação por Computador
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