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1.
Appl Opt ; 63(10): 2528-2534, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568532

RESUMO

Terahertz time-domain spectroscopy was first used to establish a correlation with the whole-rock iron (TFe) content in different depths of the Bayan Obo protolith. Compared with element content obtained by the traditional method of X-ray fluorescence spectroscopy (XRF), a similar tendency of the absorption coefficient and refractive index is presented. Furthermore, three machine learning algorithms, namely, partial least squares regression (PLSR), random forest (RF), and multi-layer perceptron (MLP), were used to develop a quantitative analytical model for TFe content of the protolith minerals. Among the three algorithms, MLP has the highest detection accuracy, with a model coefficient of determination R 2 reaching up to 0.945. These findings demonstrate that terahertz time-domain spectroscopy can be used to rapidly quantify the TFe elemental content of protolith, providing a method of detecting the content of mineral components.

2.
Soc Sci Med ; 348: 116875, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38613870

RESUMO

In 2011, China implemented tougher driving-under-the-influence laws, which criminalized driving under the influence of alcohol for the first time and increased penalties. This paper provides the first comprehensive analysis of the effects of stricter drinking policies on men's smoking behavior by using data from the 2010 and 2012 waves of the China Family Panel Studies. The results show that stricter drinking policies reduced smoking initiation and the number of cigarettes smoked per day among men by reducing the frequency and quantity of alcohol consumption. Heterogeneity analyses show that the impact of the policy is more pronounced not only for men aged 41-55, but also for men who have higher educational qualifications, who are employed, or who are not members of the Communist Party.


Assuntos
Consumo de Bebidas Alcoólicas , Fumar , Humanos , Masculino , China/epidemiologia , Adulto , Consumo de Bebidas Alcoólicas/legislação & jurisprudência , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia , Pessoa de Meia-Idade , Fumar/epidemiologia , Fumar/legislação & jurisprudência , Fumar/psicologia , Adulto Jovem , Adolescente , Dirigir sob a Influência/estatística & dados numéricos , Dirigir sob a Influência/legislação & jurisprudência , Política Pública
3.
Hepatol Commun ; 8(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437058

RESUMO

BACKGROUND: Dachshund homolog 1 (DACH1) is widely acknowledged for its involvement in regulating diverse cell fates, but its precise regulatory mechanism in ferroptosis remains elusive. In this study, we investigated whether DACH1 modulates ferroptosis through affecting P53/solute carrier family 25 member 37 (SLC25A37) signaling in hepatic fibrogenesis. METHODS: CRISPR-Cas9 system was used to knockout DACH1 in HSC to determine the effect of DACH1 on ferroptosis. Immunoprecipitation, pulldown, and mouse model of hepatic fibrogenesis were used to analyze the potential molecular mechanism of ferroptosis regulation by DACH1. RESULTS: We found that ferroptosis inducers increased the protein expression of DACH1 by suppressing the ubiquitin-proteasome signaling. DACH1 knockout can resist ferroptosis, whereas DACH1 knockin can enhance it. Interestingly, the upregulation of DACH1 resulted in the mitochondrial translocation of p53 by inducing phosphorylation at serine 392. The mutation of serine 392 can prevent the combination of DACH1 and p53, the mitochondrial translocation of p53, and DACH1-mediated ferroptosis. Moreover, SLC25A37 was identified as a candidate target for mitochondrial p53. The binding of p53 to SLC25A37 can enhance the iron uptake capacity of SLC25A37, which may cause an overload of iron in the mitochondria and hyperactive mitochondrial electron transport chain. Knockdown of SLC25A37 can impair p53-mediated mitochondrial iron overload and ferroptosis. Furthermore, treatment with erastin can induce HSC ferroptosis and relieve fibrotic lesion damage in the mouse model of hepatic fibrogenesis. HSC-specific knockdown of DACH1, p53, and SLC25A37 can abolish the induction of HSC ferroptosis and reversal of hepatic fibrogenesis by erastin treatment. CONCLUSIONS: Our findings suggest that the DACH1/P53/SLC25A37 signaling pathway is a promising target for fibrotic disorders and reveals new regulatory mechanisms of ferroptosis.


Assuntos
Ferroptose , Proteína Supressora de Tumor p53 , Animais , Camundongos , Modelos Animais de Doenças , Ferroptose/genética , Ferro , Serina , Transdução de Sinais , Proteína Supressora de Tumor p53/genética
4.
PeerJ Comput Sci ; 10: e1810, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435621

RESUMO

In this article, we address the problem of estimating fluid flows between two adjacent images containing fluid and non-fluid objects. Typically, traditional optical flow estimation methods lack accuracy, because of the highly deformable nature of fluid, the lack of definitive features, and the motion differences between fluid and non-fluid objects. Our approach captures fluid motions using an affine motion model for each small patch of an image. To obtain robust patch matches, we propose a best-buddies similarity-based method to address the lack of definitive features but many similar features in fluid phenomena. A dense set of affine motion models was then obtained by performing nearest-neighbor interpolation. Finally, dense fluid flow was recovered by applying the affine transformation to each patch and was improved by minimizing a variational energy function. Our method was validated using different types of fluid images. Experimental results show that the proposed method achieves the best performance.

5.
Sci Bull (Beijing) ; 69(7): 949-967, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38395651

RESUMO

Myocardial ischemia-reperfusion injury (MIRI) is a major hindrance to the success of cardiac reperfusion therapy. Although increased neutrophil infiltration is a hallmark of MIRI, the subtypes and alterations of neutrophils in this process remain unclear. Here, we performed single-cell sequencing of cardiac CD45+ cells isolated from the murine myocardium subjected to MIRI at six-time points. We identified diverse types of infiltrating immune cells and their dynamic changes during MIRI. Cardiac neutrophils showed the most immediate response and largest changes and featured with functionally heterogeneous subpopulations, including Ccl3hi Neu and Ym-1hi Neu, which were increased at 6 h and 1 d after reperfusion, respectively. Ym-1hi Neu selectively expressed genes with protective effects and was, therefore, identified as a novel specific type of cardiac cell in the injured heart. Further analysis indicated that neutrophils and their subtypes orchestrated subsequent immune responses in the cardiac tissues, especially instructing the response of macrophages. The abundance of Ym-1hi Neu was closely correlated with the therapeutic efficacy of MIRI when neutrophils were specifically targeted by anti-Lymphocyte antigen 6 complex locus G6D (Ly6G) or anti-Intercellular cell adhesion molecule-1 (ICAM-1) neutralizing antibodies. In addition, a neutrophil subtype with the same phenotype as Ym-1hi Neu was detected in clinical samples and correlated with prognosis. Ym-1 inhibition exacerbated myocardial injury, whereas Ym-1 supplementation significantly ameliorated injury in MIRI mice, which was attributed to the tilt of Ym-1 on the polarization of macrophages toward the repair phenotype in myocardial tissue. Overall, our findings reveal the anti-inflammatory phenotype of Ym-1hi Neu and highlight its critical role in myocardial protection during the early stages of MIRI.


Assuntos
Traumatismo por Reperfusão Miocárdica , Animais , Camundongos , Molécula 1 de Adesão Intercelular/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio , Neutrófilos
6.
Opt Lett ; 49(4): 919-922, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38359216

RESUMO

Multi-view microscopic fringe projection systems, which use high-resolution telecentric lenses and the Scheimpflug condition, face challenges in coinciding focal planes accurately, resulting in inconsistent measurements between views. In this Letter, we developed a sharpness evaluation function based on the total power of the line-spread function, which was subsequently used to generate a full-field sharpness distribution map. Then we employed the correlation between the sharpness map and orientation of the focal plane to precisely coincide the focal planes. Experimental results validate the proposed method and demonstrate its improved consistency in 3D reconstruction.

7.
Nat Chem Biol ; 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212578

RESUMO

Ferroptosis is iron-dependent oxidative cell death. Labile iron and polyunsaturated fatty acid (PUFA)-containing lipids are two critical factors for ferroptosis execution. Many processes regulating iron homeostasis and lipid synthesis are critically involved in ferroptosis. However, it remains unclear whether biological processes other than iron homeostasis and lipid synthesis are associated with ferroptosis. Using kinase inhibitor library screening, we discovered a small molecule named CGI1746 that potently blocks ferroptosis. Further studies demonstrate that CGI1746 acts through sigma-1 receptor (σ1R), a chaperone primarily located at mitochondria-associated membranes (MAMs), to inhibit ferroptosis. Suppression of σ1R protects mice from cisplatin-induced acute kidney injury hallmarked by ferroptosis. Mechanistically, CGI1746 treatment or genetic disruption of MAMs leads to defective Ca2+ transfer, mitochondrial reactive oxygen species (ROS) production and PUFA-containing triacylglycerol accumulation. Therefore, we propose a critical role for MAMs in ferroptosis execution.

8.
Acta Pharmacol Sin ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195693

RESUMO

Hepatocellular carcinoma (HCC) is one of the most common malignancy, presenting a formidable challenge to the medical community owing to its intricate pathogenic mechanisms. Although current prevention, surveillance, early detection, diagnosis, and treatment have achieved some success in preventing HCC and controlling overall disease mortality, the imperative to explore novel treatment modalities for HCC remains increasingly urgent. Epigenetic modification has emerged as pivotal factors in the etiology of cancer. Among these, RNA N6-methyladenosine (m6A) modification stands out as one of the most prevalent, abundant, and evolutionarily conserved post-transcriptional alterations in eukaryotes. The literature underscores that the dynamic and reversible nature of m6A modifications orchestrates the intricate regulation of gene expression, thereby exerting a profound influence on cell destinies. Increasing evidence has substantiated conspicuous fluctuations in m6A modification levels throughout the progression of HCC. The deliberate modulation of m6A modification levels through molecular biology and pharmacological interventions has been demonstrated to exert a discernible impact on the pathogenesis of HCC. In this review, we elucidate the multifaceted biological functions of m6A modifications in HCC, and concurrently advancing novel therapeutic strategies for the management of this malignancy.

9.
J Clin Transl Hepatol ; 12(1): 36-51, 2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38250467

RESUMO

Background and Aims: Development of fibrosis in chronic liver disease requires activation of hepatic stellate cells (HSCs) and leads to a poor outcome. Artesunate (Art) is an ester derivative of artemisinin that can induce ferroptosis in HSCs, and activated transcriptional factor 3 (ATF3) is an ATF/CREB transcription factor that is induced in response to stress. In this study, we examined the role of the Rho-associated protein kinase 1 (ROCK1)/ATF3 axis in Art-induced ferroptosis in HSCs. Methods: HSC activation and ferroptosis were studied in vitro by western blotting, polymerase chain reaction, immunofluorescence, and other assays. ATF3 electrophoretic mobility and ROCK1 protein stability were assayed by western blotting. Immunoprecipitation was used to detect the interaction of ROCK1 and ATF3, as well as ATF3 phosphorylation. A ubiquitination assay was used to verify ROCK1 degradation. Atf3-interfering and Rock1-overexpressing mice were constructed to validate the anti-hepatic fibrosis activity of Art in vivo. Results: Art induced ferroptosis in HSCs following glutathione-dependent antioxidant system inactivation resulting from nuclear accumulation of unphosphorylated ATF3 mediated by ROCK1-ubiquitination in vitro. Art also decreased carbon tetrachloride-induced liver fibrosis in mice, which was reversed by interfering with Atf3 or overexpressing Rock1. Conclusions: The ROCK1/ATF3 axis was involved in liver fibrosis and regulation of ferroptosis, which provides an experimental basis for further study of Art for the treatment of liver fibrosis.

10.
Small ; 20(15): e2307357, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38012538

RESUMO

Hydrogen reduction reaction (HER) and corrosion limit the long-life cycle of zinc-ion batteries. However, hydrophilic separators are unable to prevent direct contact between water and electrodes, and hydrophobic separators have difficulty in transporting electrolytes. In this work, an inorganic oxide-based "hydrophobic-hydrophilic-hydrophobic" self-assembled separator system is proposed. The hydrophobic layer consists of a porous structure, which can isolate a large amount of free water to avoid HER and corrosion reactions, and can transport electrolyte by binding water. The middle hydrophilic layer acts as a storage layer consisting of the GF separator, storing large amounts of electrolyte for proper circulation. By using this structure separator, Zn||Zn symmetric cell achieve 2200 h stable cycle life at 5 mA cm-2 and 1mAh cm-2 and still shows a long life of 1800 h at 10 mA cm-2 and 1mAh cm-2. The assembled Zn||VO2 full cell displays high specific capacity and excellent long-term durability of 60.4% capacity retention after 1000 cycles at 2C. The assembled Zn||VO2 pouch full cell displays high specific capacity of 172.5mAh g-1 after 40 cycles at 0.5C. Changing the inorganic oxide materials, the hydrophobic-hydrophilic-hydrophobic structure of the separators still has excellent performance. This work provides a new idea for the engineering of water-based battery separators.

11.
Hepatology ; 79(3): 606-623, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-37733267

RESUMO

BACKGROUND AND AIMS: Aerobic glycolysis reprogramming occurs during HSC activation, but how it is initiated and sustained remains unknown. We investigated the mechanisms by which canonical Wnt signaling regulated HSC glycolysis and the therapeutic implication for liver fibrosis. APPROACH AND RESULTS: Glycolysis was examined in HSC-LX2 cells upon manipulation of Wnt/ß-catenin signaling. Nuclear translocation of lactate dehydrogenase A (LDH-A) and its interaction with hypoxia-inducible factor-1α (HIF-1α) were investigated using molecular simulation and site-directed mutation assays. The pharmacological relevance of molecular discoveries was intensified in primary cultures, rodent models, and human samples. HSC glycolysis was enhanced by Wnt3a but reduced by ß-catenin inhibitor or small interfering RNA (siRNA). Wnt3a-induced rapid transactivation and high expression of LDH-A dependent on TCF4. Wnt/ß-catenin signaling also stimulated LDH-A nuclear translocation through importin ß2 interplay with a noncanonical nuclear location signal of LDH-A. Mechanically, LDH-A bound to HIF-1α and enhanced its stability by obstructing hydroxylation-mediated proteasome degradation, leading to increased transactivation of glycolytic genes. The Gly28 residue of LDH-A was identified to be responsible for the formation of the LDH-A/HIF-1α transcription complex and stabilization of HIF-1α. Furthermore, LDH-A-mediated glycolysis was required for HSC activation in the presence of Wnt3a. Results in vivo showed that HSC activation and liver fibrosis were alleviated by HSC-specific knockdown of LDH-A in mice. ß-catenin inhibitor XAV-939 mitigated HSC activation and liver fibrosis, which were abrogated by HSC-specific LDH-A overexpression in mice with fibrosis. CONCLUSIONS: Inhibition of HSC glycolysis by targeting Wnt/ß-catenin signaling and LDH-A had therapeutic promise for liver fibrosis.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia , Cirrose Hepática , Via de Sinalização Wnt , beta Catenina , Animais , Humanos , Camundongos , beta Catenina/metabolismo , Glicólise , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Lactato Desidrogenase 5/metabolismo , Via de Sinalização Wnt/fisiologia , Células Estreladas do Fígado/metabolismo
12.
Redox Biol ; 69: 102971, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38056309

RESUMO

BACKGROUND & AIMS: Although ferroptosis holds promise as a new strategy for treating hepatocellular carcinoma (HCC), there are several obstacles that need to be overcome. One major challenge is the lack of understanding about the mechanisms underlying ferroptosis. Additionally, while the m6A modification has been shown to regulate various forms of cell death, its role in regulating ferroptosis in HCC has been largely overlooked. Bridging this knowledge gap, our study aimed to elucidate the regulatory influence of m6A modification on HCC ferroptosis. MATERIALS: Dot blot and EpiQuik m6A RNA Methylation Quantitative kit detected changes in overall m6A modification level during ferroptosis in HCC. MeRIP-qPCR and RIP-qPCR identified that the m6A modification of ATG5 mRNA was significant changed. BALB/c nude mice were used to construct xenograft tumor models to verify the phenotypes upon YTHDC2 silencing. In addition, patient-derived organoid models were used to demonstrate that induction of ferroptosis was an effective strategy against HCC. RESULTS: Our study has shown that inducing ferroptosis is a promising strategy for combatting HCC. Specifically, we have found a significant correlation between ferroptosis and high levels of m6A modification in HCC. Notably, we discovered that the elevation of ATG5 mRNA m6A modification mediated by WTAP is dependent on the reading protein YTHDC2. Importantly, inhibition of either WTAP or YTHDC2 effectively prevented ferroptosis and suppressed HCC development in both in vitro and in vivo models. CONCLUSION: Our study revealed that WTAP upregulates ATG5 expression post-transcriptionally in an m6A-YTHDC2-dependent manner, thereby promoting the translation of ATG5 mRNA during ferroptosis in HCC. These findings have significant implications for the development of innovative and effective therapeutic approaches for HCC treatment.


Assuntos
Carcinoma Hepatocelular , Ferroptose , Neoplasias Hepáticas , Animais , Camundongos , Humanos , Carcinoma Hepatocelular/genética , Ferroptose/genética , Camundongos Nus , Neoplasias Hepáticas/genética , Autofagia/genética , Modelos Animais de Doenças , RNA Mensageiro
13.
Opt Express ; 31(24): 39528-39545, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38041272

RESUMO

In microscopic fringe projection profilometry (MFPP), the traditional absolute phase retrieval method using composite frequency fringe has the shortcomings of low accuracy and poor robustness due to mutual crosstalk of harmonic from the different channels of frequency-division multiplexing. In this study, an absolute phase retrieval method that avoids the inter-channel crosstalk is proposed. By introducing guard bands to accommodate the frequency channels corresponding to the second harmonic that dominate the high order harmonics, the aliasing between the second harmonic and the fundamental is eliminated. Consequently, phase maps without crosstalk can be demodulated using appropriate phase-shifting algorithms. The proposed method is well-suited for high-precision three-dimensional shape measurement scenarios in many fields such as integrated circuit manufacturing process control and micro-electro-mechanical system quality inspection. The experiment results demonstrate that the anti-crosstalk method is effective and can realize three-dimensional reconstruction for discontinuous planar surface and spherical surface.

14.
Cell Biochem Funct ; 41(8): 1076-1092, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37947373

RESUMO

COVID-19 is mainly characterized by respiratory disorders and progresses to multiple organ involvement in severe cases. With expansion of COVID-19 and SARS-CoV-2 research, correlative liver injury has been revealed. It is speculated that COVID-19 patients exhibited abnormal liver function, as previously observed in the SARS and MERS pandemics. Furthermore, patients with underlying diseases such as chronic liver disease are more susceptible to SARS-CoV-2 and indicate a poor prognosis accompanied by respiratory symptoms, systemic inflammation, or metabolic diseases. Therefore, COVID-19 has the potential to impair liver function, while individuals with preexisting liver disease suffer from much worse infected conditions. COVID-19 related liver injury may be owing to direct cytopathic effect, immune dysfunction, gut-liver axis interaction, and inappropriate medication use. However, discussions on these issues are infancy. Expanding research have revealed that angiotensin converting enzyme 2 (ACE2) expression mediated the combination of virus and target cells, iron metabolism participated in the virus life cycle and the fate of target cells, and amino acid metabolism regulated immune response in the host cells, which are all closely related to liver health. Further exploration holds great significance in elucidating the pathogenesis, facilitating drug development, and advancing clinical treatment of COVID-19-related liver injury. This article provides a review of the clinical and laboratory hepatic characteristics in COVID-19 patients, describes the etiology and impact of liver injury, and discusses potential pathophysiological mechanisms.


Assuntos
COVID-19 , Hepatopatias , Humanos , SARS-CoV-2/metabolismo , Peptidil Dipeptidase A/metabolismo , Hepatopatias/etiologia
15.
BMC Cancer ; 23(1): 1013, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37864137

RESUMO

BACKGROUND: Recent studies have shown that deficient mismatch repair (dMMR) rectal cancer may be related to treatment resistance, resulting in a worse prognosis than proficient MMR (pMMR) rectal cancer. The purpose of this study was to explore whether surgery plus other treatments (radiotherapy and chemotherapy) can bring more benefits to these patients than surgery alone. METHODS: A retrospective study of 168 patients with rectal adenocarcinoma who underwent total mesorectal excision was conducted using immunohistochemical methods to determine MMR status and a propensity score matching model to minimize potential confounding factors between subgroups of patients with different treatment regimens. Kaplan-Meier analysis, log-rank tests, and Cox regression models were used to assess overall survival (OS) and disease-free survival (DFS) in patient subgroups. RESULTS: Only 6.9% (n = 168) of patients in the total cohort had dMMR rectal adenocarcinoma, and the most common cause of dMMR was a PMS2 deletion (103, 61.3%). The median DFS of the surgery alone group was 45.7 months (IQR, 40.9 to 77.8), and the median DFS of the surgery plus other treatment group was 43.9 months (IQR, 14.2 to 80.1). The surgery alone group was superior to the surgery plus other treatment group (HR, 0.16; 95% CI, 0.07 to 0.38; p = 0.005). There was no significant difference in OS (45.8 (IQR, 41.0 to 79.8) vs. 45.9 (IQR, 38.5 to 80.3)) between the two groups (HR, 0.57; 95% CI, 0.23 to 1.40; p = 0.263). CONCLUSIONS: For patients with locally advanced dMMR rectal adenocarcinoma, compared with surgery alone, surgery plus other treatment options (radiotherapy and chemotherapy) do not grant long-term survival benefits but rather shorten DFS.


Assuntos
Adenocarcinoma , Neoplasias Retais , Humanos , Estadiamento de Neoplasias , Reparo de Erro de Pareamento de DNA , Estudos Retrospectivos , Prognóstico , Neoplasias Retais/genética , Neoplasias Retais/cirurgia , Adenocarcinoma/genética , Adenocarcinoma/cirurgia
16.
World J Clin Cases ; 11(27): 6483-6490, 2023 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-37900239

RESUMO

BACKGROUND: The pathological complete response (ypCR) rate following neoadjuvant chemotherapy for advanced gastric cancer remains low and lacks a universally accepted treatment protocol. Immunotherapy has achieved breakthrough progress. CASE SUMMARY: We report two female patients with gastric cancer defined as clinical stage cT4N1-2M0. Detection of mismatch repair protein showed mismatch repair function defect, and perioperative treatment with programmed death protein 1 inhibitor combined with S-1+oxaliplatin achieved ypCR. Surprisingly, the patients underwent clinical observation after surgery but developed different degrees of metastasis at ~6 mo after surgery. CONCLUSION: PD-1 inhibitor combined with chemotherapy provides a more strategic choice for comprehensive perioperative treatment of gastric cancer.

17.
J Appl Stat ; 50(13): 2739-2759, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37720246

RESUMO

Joint modelling of longitudinal and time-to-event data is usually described by a joint model which uses shared or correlated latent effects to capture associations between the two processes. Under this framework, the joint distribution of the two processes can be derived straightforwardly by assuming conditional independence given the random effects. Alternative approaches to induce interdependency into sub-models have also been considered in the literature and one such approach is using copulas to introduce non-linear correlation between the marginal distributions of the longitudinal and time-to-event processes. The multivariate Gaussian copula joint model has been proposed in the literature to fit joint data by applying a Monte Carlo expectation-maximisation algorithm. In this paper, we propose an exact likelihood estimation approach to replace the more computationally expensive Monte Carlo expectation-maximisation algorithm and we consider results based on using both the multivariate Gaussian and t copula functions. We also provide a straightforward way to compute dynamic predictions of survival probabilities, showing that our proposed model is comparable in prediction performance to the shared random effects joint model.

18.
Appl Opt ; 62(16): 4342-4348, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706926

RESUMO

This paper introduces a scheme of near-zero beam drift tracking technology with two-stage compression structures for the coordinate accuracy measurement of a laser tracker. The Galileo telescope system, with a magnification of 21.43, is designed to compress the beam drift in a dual-frequency interferometer. The azimuth and pitch of the beam drift are compressed to 2.41 in. and 2.92 in., and the compression rates are 95.0% and 91.9%, respectively. The improved four degrees of freedom position-sensitive detector system is used to further compress the beam drift. The peak-to-peak value of the beam drift is 0.9 in. in the azimuth direction and 2.1 in. in the pitch direction. The standard deviation of azimuth is within 0.15 in, and the pitch is within 0.43 in. The coordinate accuracy of the laser tracker can be improved 6.85 parts per million by simulation. The developed two-stage compression near-zero beam drift system can be used in the laser tracker to realize large-scale precision instrument geometric measurement.

19.
Opt Express ; 31(15): 24230-24242, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37475255

RESUMO

The laser tracker, as a new large-scale measuring instrument of combining conventional measurement technology and modern control technology, has the advantages of intelligence, portability, large measurement space, high measurement accuracy and short detection period. However, the laser tracker has strict requirements on the moving speed of the spherically mounted retroreflector. This deficiency not only limits the application of the measuring instrument in the field of high-velocity measurement, but also greatly reduces the measurement efficiency. In this work, we analyze the factors that affect the tracking velocity of the laser tracker, and propose for the first time to use the beam expander device to improve the transverse tracking measurement velocity of the instrument. The experimental results show that the laser tracker miss distance can reach 2.25 mm. The transverse tracking velocity and acceleration can reach 4.34 m/s and 2.4 g, respectively. Additionally, the acousto-optic modulator is used to increase the frequency difference between the reference beam and the measuring beam, so that the value is greater than 19 MHz. The radial tracking measurement velocity can reach 6.2 m/s. The high-velocity laser interference tracker developed by this new method can be used in the field of large-scale space precision measurement such as nuclear power, medical treatment and rail transit.

20.
Sci Rep ; 13(1): 8969, 2023 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-37268749

RESUMO

We evaluate the prognostic value of chemotherapy and other prognostic factors on overall survival among colon patients with deficient mismatch repair (dMMR), and determine the optimum time to start chemotherapy after surgery. Data of 306 colon cancer patients with dMMR who received radical surgery were collected from three Chinese centers between August 2012 and January 2018. Overall survival (OS) was assessed with the Kaplan-Meier method and log-rank. Cox regression analysis were used to assess influencing prognosis factors. The median follow-up time for all patients was 45.0 months (range, 1.0-100). There was a nonsignificant OS benefit from chemotherapy for patients with stage I and stage II disease, including high-risk stage II disease (log-rank p: 0.386, 0.779, 0.921), and a significant OS benefit for patients with stage III and stage IV disease for receiving post-operation chemotherapy (log-rank p = 0.002, 0.019). Stage III patients benefitted from chemotherapy regimens that contained oxaliplatin (log-rank p = 0.004), and Starting chemotherapy with oxaliplatin treatment earlier resulted in better outcomes (95% CI 0.013-0.857; p = 0.035). Chemotherapy regimens containing oxaliplatin can prolong the survival time of stage III and IV dMMR colon cancer patients. This beneficial manifestation was more pronounced after starting chemotherapy treatment early post operation. High risk stage II dMMR colon patients including T4N0M0 cannot benefit from chemotherapy.


Assuntos
Neoplasias do Colo , Fluoruracila , Humanos , Oxaliplatina/uso terapêutico , Fluoruracila/uso terapêutico , Reparo de Erro de Pareamento de DNA , Estadiamento de Neoplasias , Quimioterapia Adjuvante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/cirurgia , Prognóstico
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