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1.
Front Neurol ; 15: 1360741, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560728

RESUMO

Background: This study aimed to investigate the effects of adjuvant beam radiation therapy (ABRT) on overall survival (OS) in patients with primary single intracranial atypical meningioma (AM), with a focus on age-related outcomes. Methods: We conducted a retrospective study using data from SEER database. Our cohort consisted of patients diagnosed with a primary single intracranial AM tumor and had undergone surgery. The primary endpoint was OS. For survival analysis, univariable and multivariable Cox regression analysis were performed. A multivariable additive Cox model was used to assess the functional relationship between age and OS in patients with or without ABRT. Results: Of the 2,759 patients included, 1,650 underwent gross total resection and 833 received ABRT. Multivariable Cox analysis indicated that ABRT did not significantly influence OS across the entire cohort. According to the multivariable generalized additive Cox model, the relative risk of all-cause mortality increased with advancing age in both ABRT-yes and ABRT-no group. ABRT-yes had a lower relative risk than ABRT-no when age ≤ 55 years old while a higher relative risk when age > 55 years old. Subsequent multivariable Cox analysis showed that ABRT was associated with a significant lower risk for all-cause mortality in patients with age ≤ 55 years old while a significant higher risk in patients with age > 55 years old. Conclusion: Our study found that ABRT enhanced OS in younger primary single intracranial AM patients. But we also revealed a negative correlation between OS and ABRT in older patients.

2.
Appl Opt ; 63(8): 1962-1970, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38568636

RESUMO

In this paper, a dual-band terahertz metamaterial sensor based on aluminum and silicon is proposed and simulated. The aluminum surface, which is deposited on a silicon substrate, is made of a C-shaped frame resonator, a rectangular beam, and a cross. The device is insensitive to the change of incident angle in the range of 0°-30°, which shows the great transmission stability of the sensor. By examining the resonance frequency shift, it is shown that 98.3 and 237.5 GHz/RIU refractive index sensitivity can be obtained near 1.76 and 2.404 THz transmission dips of the proposed structure, respectively. The two dips can be used to sense analytes in different refractive index ranges, respectively. For Dip 1 at 1.76 THz, the range is 1.0-1.6. For Dip 2 at 2.404 THz, the range is 1.6-2.0. Different from traditional multi-band metamaterial sensors, two dips generated by the proposed device can measure continuous and non-multiplexed refractive index ranges, respectively. Because the resonance frequencies of matters are different, such a characteristic enables the device to measure different types of analyte using the appropriate resonant peak. A central-relief design is then proposed based on perturbation theory to further improve its sensing performance. The aluminum cross is covered by polyimide, which can interfere with the scattering field on the metal surface and affect the transmission results. For both transmission dips, the optimized structure realizes higher sensitivities of 111.7 GHz/RIU and 262.5 GHz/RIU, respectively. More significantly, the optimized structure also has the characteristic of a wide and non-multiplexed refractive index range. In addition, the effects of analyte thickness and polyimide layer thickness on sensor performance are also discussed. The proposed structure opens up new prospects in the design of multiple-band terahertz metamaterial sensors. It can also meet the sensing needs of biomedical, environmental monitoring, and industrial manufacturing.

3.
Front Immunol ; 15: 1290504, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38571961

RESUMO

Organoids present substantial potential for pushing forward preclinical research and personalized medicine by accurately recapitulating tissue and tumor heterogeneity in vitro. However, the lack of standardized protocols for cancer organoid culture has hindered reproducibility. This paper comprehensively reviews the current challenges associated with cancer organoid culture and highlights recent multidisciplinary advancements in the field with a specific focus on standardizing liver cancer organoid culture. We discuss the non-standardized aspects, including tissue sources, processing techniques, medium formulations, and matrix materials, that contribute to technical variability. Furthermore, we emphasize the need to establish reproducible platforms that accurately preserve the genetic, proteomic, morphological, and pharmacotypic features of the parent tumor. At the end of each section, our focus shifts to organoid culture standardization in primary liver cancer. By addressing these challenges, we can enhance the reproducibility and clinical translation of cancer organoid systems, enabling their potential applications in precision medicine, drug screening, and preclinical research.


Assuntos
Neoplasias Hepáticas , Proteômica , Humanos , Reprodutibilidade dos Testes , Neoplasias Hepáticas/patologia , Avaliação Pré-Clínica de Medicamentos , Organoides
4.
Plant Physiol ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38588053

RESUMO

Plants undergo various age-dependent changes in leaf morphology during the transition from the juvenile to the adult stage. However, the precise molecular mechanisms governing these changes in apple (Malus domestica) remain unknown. Here, we showed that CYTOKININ OXIDASE/DEHYDROGENASE5 (MdCKX5), an age-dependent gene, encodes a functional CKX enzyme and serves as the common downstream target of SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) transcription factor MdSPL14 and WRKY transcription factor MdWRKY24 to control the degradation of cytokinin (CK). As the target of mdm-microRNA156a, MdSPL14 interacts with MdWRKY24 to coordinately repress the transcription of MdCKX5 by forming the age-mediated mdm-miR156a-MdSPL14-MdWRKY24 module, which regulates age-dependent changes in CK during the juvenile-to-adult phase transition. We further demonstrated that MdARR6, a type-A ARABIDOPSIS RESPONSE REGULATOR (ARR), is a negative feedback regulator in the CK signaling pathway. Silencing of MdARR6 in apple resulted in large leaves with smaller epidermal cells and a greater number of epidermal cells. Biochemical analysis showed that the mdm-miR156a-MdSPL14-MdWRKY24 module acts as a transcriptional repressor to directly regulate MdARR6 expression, thus controlling the age-dependent changes in leaf size by reducing CK responses. These findings established a link between the age pathway and CK signaling and revealed the molecular mechanism underlying age-dependent changes during the juvenile-to-adult phase transition; our results also provide targets for the genetic improvement of the vegetative phase transition in apple.

5.
Materials (Basel) ; 17(3)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38591558

RESUMO

Inertia friction welding (IFW) was used to join large-diameter hollow bars made of Inconel 690 and 316LN successfully. The interfacial characteristics, microstructure, mechanical properties and fracture mechanism of welded joints under different process parameters were investigated. The results indicated that a joining mechanism with mechanical interlocking and metallurgical bonding was found in IFW joints. There was a significant mechanical mixing zone at the welding interface. The elemental diffusion layer was found in the "wrinkles" of the mechanical mixing zone. A tiny quantity of C elements accumulated on the friction and secondary friction surfaces. The tensile strength and impact toughness of the joints increased with the total welding energy input. Increasing the friction pressure could make the grain in all parts of the joint uniformly refined, thus enhancing the mechanical properties of welded joints. The maximum tensile strength and impact toughness of the welded joint were 639 MPa and 146 J/cm2, reaching 94% and 68% of that for Inconel 690, respectively, when the flywheel was initially set at 760 rpm, 200 MPa for friction pressure, and 388 kg/m2 for rotary inertia. Due to the Kirkendall effect in the welded joint, superior metallurgical bonding was at the welding interface close to the Inconel 690 side compared to the 316LN side.

6.
ACS Omega ; 9(14): 16519-16535, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38617621

RESUMO

Pyrite is widely distributed in lacustrine shales and has become a research focus in unconventional oil and gas exploration. Pyrite morphology is useful for identifying different types of organic matter and assessing shale oil enrichment in organic-rich shale. Abundant pyrite is developed in the source rocks from the Chang 7 Member of the Yanchang Formation in the Ordos Basin, NW China. However, the relationship between different pyrite types and the differential enrichment of shale oil still needs to be clarified. The organic geochemistry, petrology, and isotopic composition of the Chang 7 Member samples were analyzed. The significance of pyrite types and sulfur isotopic compositions as indicators of depositional environments and shale oil enrichment was emphasized. The Chang 7 shales contain three pyrite morphologies, framboidal pyrite (type A), spherulitic pyrite (type B), and euhedral and anhedral pyrite (type C), and their aggregates. The sulfur isotopic compositions of pyrite (δ34Spy) in Chang 7 shales with different pyrite types exhibited regular patterns. The δ34S values of types A, B, and C pyrites were sequentially positive overall (average values are -2.739, 2.201, and 7.487‰ in sequence), indicating that type A pyrite was formed during the syn-sedimentary to early diagenetic stage and types B and C pyrites were formed during the early to middle diagenetic stage. Types A, B, and C pyrites showed sequentially increasing kerogen type index values and kerogen carbon isotope values (mean values of -31.59, -28.70, and -26.45‰, successively), indicating that the horizons where types A, B, and C pyrites developed correspond to types I, II, and III organic matter, respectively. Strong correlations between the pyrite content and oil components reveal that pyrite indicates shale oil enrichment. Moreover, variations in pyrite type significantly influenced the enrichment behavior of shale oil. Types A and B pyrites contributing to reservoir space showed shale oil enrichment. They promoted saturated hydrocarbon enrichment at >15% pyrite content, whereas type C pyrite did not indicate shale oil enrichment. These findings provide new insights into the differential enrichment of organic matter and shale oil and valuable guidance for the large-scale exploration and development of shale oil resources.

7.
Environ Sci Technol ; 58(15): 6659-6669, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38557040

RESUMO

Revealing the role of functional redundancy is of great importance considering its key role in maintaining the stability of microbial ecosystems in response to various disturbances. However, experimental evidence on this point is still lacking due to the difficulty in "manipulating" and depicting the degree of redundancy. In this study, manipulative experiments of functional redundancy were conducted by adopting the mixed inoculation strategy to evaluate its role in engineered anaerobic digestion systems under ammonium inhibition conditions. The results indicated that the functional redundancy gradient was successfully constructed and confirmed by evidence from pathway levels. All mixed inoculation groups exhibited higher methane production regardless of the ammonium level, indicating that functional redundancy is crucial in maintaining the system's efficiency. Further analysis of the metagenome-assembled genomes within different functional guilds revealed that the extent of redundancy decreased along the direction of the anaerobic digestion flow, and the role of functional redundancy appeared to be related to the stress level. The study also found that microbial diversity of key functional populations might play a more important role than their abundance on the system's performance under stress. The findings provide direct evidence and highlight the critical role of functional redundancy in enhancing the efficiency and stability of anaerobic digestion.


Assuntos
Compostos de Amônio , Microbiota , Anaerobiose , Reatores Biológicos , Metagenoma , Metano
9.
Opt Express ; 32(7): 12081-12091, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38571041

RESUMO

The traditional analysis method for super multi-view 3D display based on geometric optics, which approximates the lenticular lenses as a series of pinhole structures, ignored the chromatic aberration. In this paper, the optimization method based on diffraction theory is proposed for super multi-view 3D display, where the wavefronts are evaluated accurately by the forward propagation method, and the chromatic aberration of the synthetic viewpoint image is reduced dramatically by the backward reconstruction optimization method (BROM). The optical experiment is performed to verify the feasibility of the method, which is consistent with numerical simulation results. It is proved that the proposed method simulates the physical propagation process of super multi-view 3D display and improves the reconstructed image quality. In the future, it can be used to achieve the super multi-view 3D light field technology with low crosstalk.

10.
Mol Plant ; 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38581129

RESUMO

The phytohormone auxin plays a pivotal role in governing plant growth and development. While the TRANSPORT INHIBITOR RESPONSE1/AUXIN SIGNALING F-BOX (TIR1/AFBs) receptors function in both the nucleus and cytoplasm, the mechanism governing the distribution of TIR1/AFBs between these small cellular compartments remains unknown. In this study, we demonstrate that auxin-mediated oxidation of TIR1/AFB2 is essential for their targeting to the nucleus. Our findings reveal that small active molecules, reactive oxygen species (ROS) and nitric oxide (NO), are indispensable for the nucleo-cytoplasmic distribution of TIR1/AFB2 in trichoblasts and root hairs. This process is regulated by the FERONIA receptor kinase-NADPH oxidase signaling pathway. ROS and NO initiate oxidative modifications in TIR1C140/516 and AFB2C135/511, facilitating their subsequent nuclear import. The oxidized forms of TIR1C140/516 and AFB2C135/511 play a crucial role in enhancing the functionality of TIR1 and AFB2 in transcriptional auxin responses. In summary, our study unveils a novel mechanism through which auxin stimulates the transportation of TIR1/AFB2 from the cytoplasm to the nucleus, orchestrated by the FERONIA-ROS signaling pathway.

11.
Artigo em Inglês | MEDLINE | ID: mdl-38581328

RESUMO

Objective: The measurement of the right and left axillary arteries and aortic arch and their vessels by multi-row spiral CT angiography provides the basis for clinical catheter selection and depth for axillary artery placement. This study reported the clinical experience of 7 patients who successfully underwent ultrasound-guided percutaneous axillary artery cannulation for veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Methods: Patients who had CT angiography of the thoracic aorta at our institution between January 2020 and March 2022 were assessed for eligibility and included. The diameters of the cephalic trunk (D1), right common carotid artery (D2), right axillary artery (D3), left common carotid artery (D4), left axillary artery opening (D5), right axillary artery cannulation length (L1), and left axillary artery cannulation length (L2) were measured. The tangential angles α, ß, and γ of the cephalic trunk, left common carotid artery and left subclavian and aorta was measured using an automatic angle-forming tool. The decision to use a 15F cannula for ultrasound-guided percutaneous axillary artery cannulation in veno-arterial extracorporeal membrane oxygenation (VA-ECMO) aims to achieve optimal vascular access. This cannula size strikes a balance, providing sufficient blood flow rates for ECMO support while minimizing the risk of complications associated with larger cannulas. Precise measurements of arterial dimensions, including the cephalic trunk, common carotid arteries, and axillary arteries, play a crucial role in guiding catheter selection and determining the depth of axillary artery placement. These measurements allow for tailored approaches based on individual patient characteristics, enhancing the safety and efficacy of the intervention. Additionally, measuring tangential angles (α, ß, and γ) provides insights into arterial alignment, optimizing the cannula trajectory for efficient blood flow. The use of an automatic angle-forming tool enhances measurement precision, contributing to procedural accuracy, minimizing complications, and ensuring the success of ultrasound-guided percutaneous axillary artery cannulation. In summary, the choice of a 15F cannula and precise measurements are essential components of the methodology, emphasizing safety, efficacy, and personalized approaches in VA-ECMO. From March to June 2022, 7 patients (6 males and 1 female) in our intensive care medicine department underwent successful ultrasound-guided percutaneous axillary artery cannulation for VA-ECMO with 15F cannula, including 3 cases with extracorporeal cardiopulmonary resuscitation (ECPR) and 4 cases with circulatory collapse. Results: 292 patients met the study criteria, 215 males and 77 females, with a mean age of 67.2±14.2 years. The measurements showed that D1 was (13.1±2.0) mm, D2 was (8.8±2.5) mm, D3 was (6.1±1.2) mm, D4 was (8.3±3.5) mm, D5 was (6.1±1.1) mm, L1 was (114.1±17.8) mm, and L2 was (128.4±20.2) mm. The tangential angles α of the cephalic trunk left common carotid artery and left subclavian artery to the aorta were (43.8°±17.1°), ß was (50.7°±14.8°), and γ was (62.4°±19.1°). Males had significantly wider D3 and D5, longer L1 and L2, and smaller gamma angles than females (P < .05). Three ECPR cases showed no recovery of the spontaneous heartbeat with femoral artery cannulation for VA-ECMO but recovered spontaneous heartbeat after axillary artery cannulation for VA-ECMO was adopted. The measurements in this study have important implications for veno-arterial extracorporeal membrane oxygenation (VA-ECMO) procedures. They provide crucial information about arterial dimensions, including the cephalic trunk, common carotid arteries, and axillary arteries. This information guides clinicians in selecting catheters and determining the ideal depth for percutaneous axillary artery cannulation during ECMO interventions. Notable gender differences in arterial dimensions highlight the need for personalized approaches in ECMO procedures. Customizing catheter choices and cannulation depth based on individual patient characteristics, informed by these measurements, improves the safety and effectiveness of the intervention. The measured tangential angles (α, ß, and γ) offer insights into arterial alignment, crucial for optimizing cannula trajectory and ensuring proper alignment for efficient blood flow. The use of an automatic angle-forming tool enhances measurement precision, contributing to procedural accuracy and minimizing the risk of complications during ECMO procedures. In summary, these measurements directly enhance the precision and safety of VA-ECMO procedures, underscoring the importance of personalized approaches based on individual anatomical variations and improving overall intervention success and outcomes. Conclusion: Ultrasound-guided percutaneous axillary artery cannulation for VA-ECMO with a 15F cannula is clinically feasible. Axillary artery cannulation for VA-ECMO contributes to the restoration of spontaneous heartbeat in ECPR patients more than femoral artery cannulation, and the possible mechanism is a better improvement of coronary blood flow. However, the study has limitations, including a modest sample size and a single-center, retrospective design, impacting its generalizability. To validate and extend these findings, further research with larger and diverse cohorts, including prospective investigations, is necessary to ensure their applicability across various clinical settings and patient demographics in VA-ECMO.

12.
Ecotoxicol Environ Saf ; 276: 116288, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38581909

RESUMO

Cylindrospermopsin (CYN), a cyanobacterial toxin, has been detected in the global water environment. However, information concerning the potential environmental risk of CYN is limited, since the majority of previous studies have mainly focused on the adverse health effects of CYN through contaminated drinking water. The present study reported that CYN at environmentally relevant levels (0.1-100 µg/L) can significantly enhance the conjugative transfer of RP4 plasmid in Escherichia coli genera, wherein application of 10 µg/L of CYN led to maximum fold change of ∼6.5- fold at 16 h of exposure. Meanwhile, evaluation of underlying mechanisms revealed that environmental concentration of CYN exposure could increase oxidative stress in the bacterial cells, resulting in ROS overproduction. In turn, this led to an upregulation of antioxidant enzyme-related genes to avoid ROS attack. Further, inhibition of the synthesis of glutathione (GSH) was also detected, which led to the rapid depletion of GSH in cells and thus triggered the SOS response and promoted the conjugative transfer process. Increase in cell membrane permeability, upregulation of expression of genes related to pilus generation, ATP synthesis, and RP4 gene expression were also observed. These results highlight the potential impact on the spread of antimicrobial resistance in water environments.

13.
Dev Cell ; 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38582082

RESUMO

The commitment and differentiation of human placental progenitor cytotrophoblast (CT) cells are crucial for a successful pregnancy, but the underlying mechanism remains poorly understood. Here, we identified the transcription factor (TF), specificity protein 6 (SP6), as a human species-specific trophoblast lineage TF expressed in human placental CT cells. Using pluripotent stem cells as a model, we demonstrated that SP6 controls CT generation and the establishment of trophoblast stem cells (TSCs) and identified msh homeobox 2 (MSX2) as the downstream effector in these events. Mechanistically, we showed that SP6 interacts with histone acetyltransferase P300 to alter the landscape of H3K27ac at targeted regulatory elements, thereby favoring transcriptional activation and facilitating CT cell fate decisions and TSC maintenance. Our results established SP6 as a regulator of the human trophoblast lineage and implied its role in placental development and the pathogenies of placental diseases.

14.
Zookeys ; 1197: 1-11, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38616922

RESUMO

Two new mealybug species, Paracoccusgillianwatsonae Zhang, sp. nov. and P.wui Zhang, sp. nov., collected from Jiangxi, South China, are described and illustrated based on the morphology of adult females. Paracoccusgillianwatsonae is similar to P.burnerae (Brain, 1915), but it differs in having fewer pairs of cerarii, and in lacking both ventral oral collar tubular ducts on the margins of the head and translucent pores on the hind femur. Paracoccuswui resembles P.keralae Williams, 2004 and P.neocarens (Lit, 1992), but it differs in lacking ventral oral collar tubular ducts on the margins of the head and in having multilocular disc-pores usually in double rows at the posterior edges of abdominal segments V and VI. A key to the Paracoccus species found in China is provided.

15.
Heliyon ; 10(7): e28242, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38601669

RESUMO

Introduction: The close association between cuproptosis and tumor immunity in triple-negative breast cancer (TNBC) allows its monitoring for predicting the prognosis of patients with TNBC. Nevertheless, the biological function and prognostic value of cuproptosis-related miRNAs and their target genes have not been reported. Purpose: To construct the miRNA and mRNA-based risk models associated with cuproptosis for patients with TNBC. Methods: Comparison of expression levels for genes associated with cuproptosis was executed between patients in the normal individuals and the TCGA-TNBC cohort. Conducting differential analysis resulted in the identification of differentially expressed miRNA (DE-miRNAs) and differentially expressed genes (DEGs) between the TNBC and Control samples. Screening for prognostic miRNAs and biomarkers involved employing univariate Cox analysis and least absolute shrinkage and selection operator regression analyses. These methods were utilized to construct risk models aimed at predicting the survival of patients with TNBC. Based on the median value of risk scores, patients were then stratified into low- and high-risk groups. Functional enrichment analysis was employed to explore the potential function and pathways of prognostic genes. Additionally, independent prognostic analysis was performed through univariate and multivariate Cox regression. Immune infiltration analysis was performed to examine disparities in the infiltration of immune cells between the two risk groups. Finally, the prognostic gene expression was mined in key cell types of TNBC. Results: We obtained 5213 DEGs and 204 DE-miRNAs related to cuproptosis between TNBC and Control samples. Five prognostic miRNAs (miR-203a-3p, miR-1277-3p, miR-135b-5p, miR-200c-3p, and miR-592) and three biomarkers (DENND5B, IGF1R, and MEF2C) were closely associated with TNBC. Significant differences in the functions of prognostic genes between the two risk groups were observed, encompassing adipogenesis, inflammatory response, and hormone metabolic process. The prognostic gene regulatory network revealed that miR200C-3p regulated ZFPM2 and CFL2, and miR-1277-3p regulated BMP2 and RORA. A nomogram was created based on riskScore, cancer status, and pathologic stage to predict 1/3/5-year survival of patients with TNBC. Immune infiltration analysis indicated that the immune microenvironment may be associated with the progression of TNBC. Interestingly, prognostic genes exhibited higher expression levels in T cells, fibroblasts, endothelial cells, and monocytes compared to other cells. Conclusions: Five prognostic miRNA (miR-203a-3p, miR-1277-3p, miR-135b-5p, miR-200c-3p, and miR-592) and three biomarkers (DENND5B, IGF1R, and MEF2C) were significantly associated with TNBC, it provides new therapeutic targets for the treatment and prognosis of TNBC.

16.
J Phys Chem A ; 128(16): 3170-3179, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38624170

RESUMO

We perform a high-level ab initio study on 20 electronic states of monochlorosilylene (HSiCl) using an internally contracted multireference configuration interaction method including Davidson correction (icMRCI+Q). The spin-orbit coupling (SOC) effect is investigated, leading to splitting of the 20 spin-orbit-free states into 50 spin-orbit-coupled states. Vertical transition energies, oscillator strengths, and potential energy curves are presented with and without considering the SOC effect. Analysis indicates that the SOC effect plays an important role, especially for the high-lying excited states of HSiCl. The state interaction and the dynamics of the electronic states of HSiCl in the ultraviolet region are discussed based on our calculation results. Our study paves the way to understanding the behavior of electronic excited states of monochlorosilylene.

17.
Org Lett ; 26(15): 3004-3009, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38573817

RESUMO

A well-defined Ru(II)-PNP complex demonstrated high activity in the anti-Markovnikov hydroalkylation of nonpolarized terminal alkenes via hydrazones. Hydrazone served as a carbanion equivalent to combine with the electrophilic alkene substrate upon activation by the ruthenium catalyst, forming a new C-C bond in a concerted pathway with N2 as the only theoretical byproduct. Experimental and computational studies suggested the existence of a push-pull interaction that activated the alkene for hydrazone addition and then deduced the mechanism.

18.
J Clin Pharmacol ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639103

RESUMO

Trilaciclib is a first-in-class, intravenous cyclin-dependent kinase 4 and 6 inhibitor approved for reducing the incidence of chemotherapy-induced myelosuppression in adult patients with extensive-stage small cell lung cancer receiving a platinum/etoposide-containing or topotecan-containing regimen. No dose adjustment is recommended for participants with mild hepatic impairment (HI) based on previous population pharmacokinetic (PK) analysis. This open-label, parallel-group study examined the impact of moderate and severe HI on the PK of trilaciclib. The study employed a reduced study design. Participants with moderate (Child-Pugh B, n = 8) and severe (Child-Pugh C, n = 5) HI and matched healthy controls (n = 11) received a single intravenous dose of trilaciclib 100 mg/m2. The unbound fraction of trilaciclib was comparable between the HI groups and the matched healthy control group. The unbound trilaciclib extent of exposure (i.e., area under the concentration-time curve) in participants with moderate and severe HI was ∼40% and ∼60% higher, respectively, compared with healthy matched controls based on Child-Pugh classification. Ad hoc analysis using National Cancer Institute classification showed similar results. The US Food and Drug Administration-approved trilaciclib dose of 240 mg/m2 should be reduced by ∼30%, to 170 mg/m2, for patients with moderate or severe HI.

20.
Comput Med Imaging Graph ; 115: 102378, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38640621

RESUMO

Current methods of digital pathological images typically employ small image patches to learn local representative features to overcome the issues of computationally heavy and memory limitations. However, the global contextual features are not fully considered in whole-slide images (WSIs). Here, we designed a hybrid model that utilizes Graph Neural Network (GNN) module and Transformer module for the representation of global contextual features, called TransGNN. GNN module built a WSI-Graph for the foreground area of a WSI for explicitly capturing structural features, and the Transformer module through the self-attention mechanism implicitly learned the global context information. The prognostic markers of hepatocellular carcinoma (HCC) prognostic biomarkers were used to illustrate the importance of global contextual information in cancer histopathological analysis. Our model was validated using 362 WSIs from 355 HCC patients diagnosed from The Cancer Genome Atlas (TCGA). It showed impressive performance with a Concordance Index (C-Index) of 0.7308 (95% Confidence Interval (CI): (0.6283-0.8333)) for overall survival prediction and achieved the best performance among all models. Additionally, our model achieved an area under curve of 0.7904, 0.8087, and 0.8004 for 1-year, 3-year, and 5-year survival predictions, respectively. We further verified the superior performance of our model in HCC risk stratification and its clinical value through Kaplan-Meier curve and univariate and multivariate COX regression analysis. Our research demonstrated that TransGNN effectively utilized the context information of WSIs and contributed to the clinical prognostic evaluation of HCC.

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