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1.
Blood ; 142(19): 1658-1671, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37624904

RESUMO

Iron is an essential nutrient required by all cells but used primarily for red blood cell production. Because humans have no effective mechanism for ridding the body of excess iron, the absorption of dietary iron must be precisely regulated. The critical site of regulation is the transfer of iron from the absorptive enterocyte to the portal circulation via the sole iron efflux transporter, ferroportin. Here, we report that poly(rC)-binding protein 1 (PCBP1), the major cytosolic iron chaperone, is necessary for the regulation of iron flux through ferroportin in the intestine of mice. Mice lacking PCBP1 in the intestinal epithelium exhibit low levels of enterocyte iron, poor retention of dietary iron in enterocyte ferritin, and excess efflux of iron through ferroportin. Excess iron efflux occurred despite lower levels of ferroportin protein in enterocytes and upregulation of the iron regulatory hormone hepcidin. PCBP1 deletion and the resulting unregulated dietary iron absorption led to poor growth, severe anemia on a low-iron diet, and liver oxidative stress with iron loading on a high-iron diet. Ex vivo culture of PCBP1-depleted enteroids demonstrated no defects in hepcidin-mediated ferroportin turnover. However, measurement of kinetically labile iron pools in enteroids competent or blocked for iron efflux indicated that PCBP1 functioned to bind and retain cytosolic iron and limit its availability for ferroportin-mediated efflux. Thus, PCBP1 coordinates enterocyte iron and reduces the concentration of unchaperoned "free" iron to a low level that is necessary for hepcidin-mediated regulation of ferroportin activity.


Assuntos
Proteínas de Transporte de Cátions , Sobrecarga de Ferro , Humanos , Camundongos , Animais , Ferro/metabolismo , Hepcidinas/genética , Hepcidinas/metabolismo , Ferro da Dieta/metabolismo , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Intestinos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo
2.
J Am Chem Soc ; 146(25): 17158-17169, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38874447

RESUMO

Understanding Li-ion transport is key for the rational design of superionic solid electrolytes with exceptional ionic conductivities. LiNbOCl4 is reported to be one of the most highly conducting materials in the recently realized new class of soft oxyhalide solid electrolytes, exhibiting an ionic conductivity of ∼11 mS·cm-1. Here, we apply X-ray/neutron diffraction and pair distribution function analysis─coupled with density functional theory/ab initio molecular dynamics (AIMD)─to determine a structural model that provides a rationale for the high conductivity that we observe experimentally in this nanocrystalline solid. We show that it arises from unusually high framework flexibility at room temperature. This is due to isolated 1-D [NbOCl4]- anionic chains that exhibit energetically favorable orientational disorder that is─in turn─correlated to multiple, disordered, and equi-energetic Li+ sites in the lattice. As the Li ions sample the 3-D energy landscape with a fast predicted diffusion coefficient of 5.1 × 10-7 cm2/s at room temperature (σicalc = 17.4 mS·cm-1), the inorganic polymer chains can reorient or vice versa. The activation energy barrier for Li migration through the frustrated energy landscape is especially reduced by the elastic nature of the NbO2Cl4 octahedra evident from very widely dispersed Cl-Nb-Cl bond angles in AIMD simulations at 300 K. The phonon spectra are predominantly influenced by Cl vibrations in the low energy range, and there is a strong overlap between the framework (Cl, Nb) and Li partial density of states in the region between 1.2 and 4.0 THz. The framework flexibility is also reflected in a relatively low bulk modulus of 22.7 GPa. Our findings pave the way for the investigation of future "flex-ion" inorganic solids and open up a new direction for the design of high-conductivity, soft solid electrolytes for all-solid-state batteries.

3.
BMC Plant Biol ; 24(1): 563, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38879466

RESUMO

BACKGROUND: Drought is a leading environmental factor affecting plant growth. To explore the drought tolerance mechanism of asparagus, this study analyzed the responses of two asparagus varieties, namely, 'Jilv3' (drought tolerant) and 'Pacific Early' (drought sensitive), to drought stress using metabolomics and transcriptomics. RESULTS: In total, 2,567 and 7,187 differentially expressed genes (DEGs) were identified in 'Pacific Early' and 'Jilv3', respectively, by comparing the transcriptome expression patterns between the normal watering treatment and the drought stress treatment. These DEGs were significantly enriched in the amino acid biosynthesis, carbon metabolism, phenylpropanoid biosynthesis, and plant hormone signal transduction pathways. In 'Jilv3', DEGs were also enriched in the following energy metabolism-related pathways: citrate cycle (TCA cycle), glycolysis/gluconeogenesis, and pyruvate metabolism. This study also identified 112 and 254 differentially accumulated metabolites (DAMs) in 'Pacific Early' and 'Jilv3' under drought stress compared with normal watering, respectively. The amino acid, flavonoid, organic acid, and soluble sugar contents were more significantly enhanced in 'Jilv3' than in 'Pacific Early'. According to the metabolome and transcriptome analysis, in 'Jilv3', the energy supply of the TCA cycle was improved, and flavonoid biosynthesis increased. As a result, its adaptability to drought stress improved. CONCLUSIONS: These findings help to better reveal the molecular mechanism underlying how asparagus responds to drought stress and improve researchers' ability to screen drought-tolerant asparagus varieties as well as breed new varieties.


Assuntos
Asparagus , Secas , Metabolômica , Transcriptoma , Asparagus/genética , Asparagus/metabolismo , Asparagus/fisiologia , Perfilação da Expressão Gênica , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Metaboloma
4.
Opt Express ; 32(11): 20146-20152, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859131

RESUMO

Sapphire is a promising wideband substrate material for visible photonics. It is a common growth substrate for III-nitride light-emitting diodes and laser structures. Doped sapphires are important gain media foundational to the development of titanium-sapphire and ruby lasers. For lasers operating at visible and near-infrared wavelengths, a photonic platform that minimizes loss while maximizing gain material overlap is crucial. Here, we introduce a novel low-loss waveguiding strategy that establishes high-performance integrated photonics on sapphire substrates. This platform achieves a high intrinsic quality factor of 5.6 million near 780 nm and features direct compatibility with a range of solid-state laser gain media.

5.
Chemistry ; 30(37): e202401463, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38699856

RESUMO

Aqueous zinc-ion batteries are anticipated to be the next generation of important energy storage devices to replace lithium-ion batteries due to the ongoing use of lithium resources and the safety hazards associated with organic electrolytes in lithium-ion batteries. Manganese-based compounds, including MnOx materials, have prominent places among the many zinc-ion battery cathode materials. Additionally, Cu doping can cause the creation of an oxygen vacancy, which increases the material's internal electric field and enhances cycle stability. MnOx also has great cyclic stability and promotes ion transport. At a current density of 0.2 A g-1, the Cu/MnOx nanocomposite obtained a high specific capacitance of 304.4 mAh g-1. In addition, Cu/MnOx nanocomposites showed A high specific capacity of 198.9 mAh g-1 after 1000 cycles at a current density of 0.5 A g-1. Therefore, Cu/MnOx nanocomposites are expected to be a strong contender for the next generation of zinc-ion battery cathode materials in high energy density storage systems.

6.
Syst Biol ; 72(3): 639-648, 2023 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-36856704

RESUMO

The Lowest Radial Distance (LoRaD) method is a modification of the recently introduced Partition-Weighted Kernel method for estimating the marginal likelihood of a model, a quantity important for Bayesian model selection. For analyses involving a fixed tree topology, LoRaD improves upon the Steppingstone or Thermodynamic Integration (Path Sampling) approaches now in common use in phylogenetics because it requires sampling only from the posterior distribution, avoiding the need to sample from a series of ad hoc power posterior distributions, and yet is more accurate than other fast methods such as the Generalized Harmonic Mean (GHM) method. We show that the method performs well in comparison to the Generalized Steppingstone method on an empirical fixed-topology example from molecular phylogenetics involving 180 parameters. The LoRaD method can also be used to obtain the marginal likelihood in the variable-topology case if at least one tree topology occurs with sufficient frequency in the posterior sample to allow accurate estimation of the marginal likelihood conditional on that topology. [Bayesian; marginal likelihood; phylogenetics.].


Assuntos
Filogenia , Funções Verossimilhança , Teorema de Bayes
7.
Ann Hematol ; 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38886192

RESUMO

BACKGROUND: The interaction between CD47 and signal-regulatory protein-alpha (SIRPα) inhibits phagocytosis, and their clinicopathological characteristics have been evaluated in various diseases. However, the significance of CD47 and SIRPα expression, as well as the combined effect, in Extranodal Natural killer/T-cell Lymphoma (ENKTL) remains uncertain. METHODS: In total, 76 newly diagnosed ENKTL patients (mean age 49.9 years, 73.7% male) were included in this study. CD47 and SIRPα expression were examined by immunohistochemistry. Survival analyses were conducted through Kaplan-Meier curves and the Cox regression model. RESULTS: Seventy-one (93.4%) cases were categorized as the CD47 positive group and 59 (77.6%) cases were categorized as the SIRPα positive group. CD47-negative cases had more advanced-stage illness (P = 0.001), while SIRPα-positive cases showed significantly lower levels of high-density lipoprotein (P < 0.001). In univariable analysis, CD47, SIRPα expression, and their combination were significantly associated with prognosis (P < 0.05). In multivariable analysis, only positive SIRPα expression remained significantly associated with superior overall survival (Hazard ratio [HR] 0.446; 95% confidence interval [CI] 0.207-0.963; P = 0.004). Furthermore, SIRPα expression could re-stratify the survival of patients in ECOG (< 2), advanced CA stage, PINK (HR), CD38-positive, PD1-positive, and CD30-positive groups. CONCLUSIONS: SIRPα status was a potential independent prognostic factor for ENKTL. The prognostic significance of CD47 expression and the interaction between CD47 and SIRPα in ENKTL need further investigation.

8.
J Pineal Res ; 76(1): e12929, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38047407

RESUMO

Cholestatic liver disease is characterized by disturbances in the intestinal microbiota and excessive accumulation of toxic bile acids (BA) in the liver. Melatonin (MT) can improve liver diseases. However, the underlying mechanism remains unclear. This study aimed to explore the mechanism of MT on hepatic BA synthesis, liver injury, and fibrosis in 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-fed and Mdr2-/- mice. MT significantly improved hepatic injury and fibrosis with a significant decrease in hepatic BA accumulation in DDC-fed and Mdr2-/- mice. MT reprogramed gut microbiota and augmented fecal bile salt hydrolase activity, which was related to increasing intestinal BA deconjugation and fecal BA excretion in both DDC-fed and Mdr2-/- mice. MT significantly activated the intestinal farnesoid X receptor (FXR)/fibroblast growth factor 15 (FGF-15) axis and subsequently inhibited hepatic BA synthesis in DDC-fed and Mdr2-/- mice. MT failed to improve DDC-induced liver fibrosis and BA synthesis in antibiotic-treated mice. Furthermore, MT provided protection against DDC-induced liver injury and fibrosis in fecal microbiota transplantation mice. MT did not decrease liver injury and fibrosis in DDC-fed intestinal epithelial cell-specific FXR knockout mice, suggesting that the intestinal FXR mediated the anti-fibrosis effect of MT. In conclusion, MT ameliorates cholestatic liver diseases by remodeling gut microbiota and activating intestinal FXR/FGF-15 axis-mediated inhibition of hepatic BA synthesis and promotion of BA excretion in mice.


Assuntos
Colestase , Hepatopatias , Melatonina , Camundongos , Animais , Melatonina/farmacologia , Melatonina/metabolismo , Fígado/metabolismo , Colestase/tratamento farmacológico , Colestase/metabolismo , Colestase/patologia , Hepatopatias/metabolismo , Hepatopatias/patologia , Ácidos e Sais Biliares/metabolismo , Ácidos e Sais Biliares/farmacologia , Camundongos Knockout , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Camundongos Endogâmicos C57BL
9.
Jpn J Clin Oncol ; 54(1): 89-96, 2024 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-37721193

RESUMO

OBJECTIVE: Numerous scattered case studies continue to demonstrate a strong correlation between acquired KRAS mutations and epidermal growth factor receptor-tyrosine kinase inhibitor resistance in non-small cell lung cancer. However, the comprehensive understanding of the KRAS pathway following the failure of epidermal growth factor receptor-tyrosine kinase inhibitor therapy remains limited. METHODS: We conducted a retrospective evaluation of the next generation sequencing data from 323 patients with advanced non-small cell lung cancer and EGFR-activating mutations after experiencing progression with epidermal growth factor receptor-tyrosine kinase inhibitor therapy. Our analysis specifically focused on the acquired changes to the KRAS gene. RESULTS: Among the 323 patients with advanced non-small cell lung cancer and EGFR-activating mutations who experienced resistance to epidermal growth factor receptor-tyrosine kinase inhibitor therapy, 14 individuals (4.3%) developed resistance due to acquired KRAS alterations. Of these 14 patients, 10 cases (71.4%) were due to KRAS missense mutations, 1 case (7.2%) was due to KRAS gene fusion and 3 cases (21.4%) were due to KRAS amplification. Notably, we identified one newly demonstrated KRAS gene fusion (KRAS and LMNTD1), one KRAS G13D and one KRAS K117N. The emergence of acquired KRAS alterations was often accompanied by novel mutations and high tumor mutation burden, with TP53, CNKN2A, PIK3CA, MYC, STK11, CDK4, BRCA2 and ERBB2 being the most frequently observed concurrent mutations. The median progression-free survival and overall survival for the 14 patients were 5.2 and 7.3 months, respectively. Acquired KRAS missense variants were associated with significantly worse progression-free survival compared with other KRAS variant subtypes (P < 0.028). CONCLUSIONS: This study provides significant evidence of the role of acquired KRAS variants in the development of resistance to epidermal growth factor receptor-tyrosine kinase inhibitor therapy. Our results contribute to the growing body of knowledge on the mutational profiles associated with resistance to epidermal growth factor receptor-tyrosine kinase inhibitor treatment. Furthermore, our study highlights the KRAS gene change as a significant mechanism of resistance to epidermal growth factor receptor-tyrosine kinase inhibitor therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , Estudos Retrospectivos , Inibidores de Proteínas Quinases/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Quinazolinas , Receptores ErbB/genética , Mutação , Resistencia a Medicamentos Antineoplásicos/genética
10.
J Oncol Pharm Pract ; : 10781552241259354, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38839571

RESUMO

INTRODUCTION: Tyrosine kinase inhibitors (TKIs) have been used as the first-line treatment for many patients with renal cell carcinoma (RCC), the seventh most common cancer in the United Kingdom. However, suboptimal adherence to TKIs can result in poor clinical prognosis. This study quantified RCC patients' adherence to TKIs and explored factors associated with suboptimal adherence. METHOD: This retrospective cohort study was conducted at a specialist oncology tertiary hospital in Northwest England, using pharmacy dispensing records between November 2021 and March 2022. TKI prescriptions dispensed to patients with RCC were extracted to calculate the persistency gaps (≥7 or ≥14 days) and medication possession ratio (MPR). Multilevel regression analysis was conducted to associate MPR and persistency gaps with specific patient-related and TKI-related factors. This study did not require ethics approval. RESULTS: Of the 2225 prescriptions dispensed to 109 patients, 469 (23.4%) and 274 (13.7%) persistency gaps of ≥7 and ≥14 days were identified. About 75% and 92% of patients had a persistency gap of ≥7 days within the first 90 days and 180 days. The length of time since the first TKI prescription (p < 0.001) and the use of sunitinib(p = 0.003) were significantly associated with the number of prescription gaps of ≥7 days. Moreover, the median MPR was 95.6% (interquartile range: 90.7%, 100.1%). Similarly, the length of time since the first TKI prescription was dispensed (p < 0.001) and the use of sunitinib (p = 0.034) were significantly associated with MPR. DISCUSSION AND CONCLUSION: This single-centre study found that patients with RCC generally adhere to TKIs (MPR > 90%), but many patients experienced a persistency gap. The crucial window to mitigate TKI utilisation is within 180 days after the initial dispensing of TKIs. Further large-scale studies are required to comprehensively investigate other factors associated with adherence to TKIs and develop interventions to improve adherence and medication use problems.

11.
Neurosurg Rev ; 47(1): 35, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38183517

RESUMO

Clear cell meningiomas are a rare histological subtype of World Health Organization (WHO) grade II meningioma. Despite its relatively low frequency, clear cell meningioma has attracted considerable attention because of its unique pathological characteristics, clinical behavior, and challenging management considerations. The purpose of our systematic review is to provide clinicians with a better understanding of this rare disease. PubMed was searched for articles in the English language published from 1988 to 2023 June. The keywords were as follows: "clear cell meningioma," "clear cell" and "meningioma." We analyzed clinical manifestations, radiological manifestations, pathological features, comprehensive treatment strategies, and prognosis to determine the factors influencing recurrence-free survival (RFS). Recurrence-free survival curves of related factors were calculated by the Kaplan‒Meier method. The log-rank test and Cox univariate analysis were adopted to assess the intergroup differences and seek significant factors influencing prognosis and recurrence. Fifty-seven papers met the eligibility criteria, including 207 cases of clear cell meningioma (CCM), which were confirmed by postoperative pathology. The fifty-seven articles involved 84 (40.6%) males and 123 (59.4%) females. The average age at diagnosis was 27.9 years (range, 14 months to 84 years). Among the symptoms observed, headache, neurologic deficit, and hearing loss were the most commonly reported clinical manifestations. Most tumors (47.8%) were located in the skull base region. Most tumors showed significant enhancement, and homogeneous enhancement was more common. A total of 152 (74.1%) patients underwent gross total resection (GTR), and 53 (25.9%) patients underwent subtotal resection (STR). During the follow-up, the tumor recurred in 80 (39.4%) patients. The log-rank test and the Cox univariate analysis revealed that tumor resection range (GTR vs. STR) and adjuvant treatment (YES vs. NO) were significant predictors of recurrence-free survival (RFS). Clear cell meningioma is a rare type of meningioma with challenging diagnosis and therapy. The prognosis of this disease is different from that of regular meningiomas. Recurrence remains a possibility even after total tumor resection. We found that the surgical resection range and adjuvant treatment affected the recurrence period. This finding provides significant guidance for the treatment of clear cell meningioma.


Assuntos
Neoplasias Meníngeas , Meningioma , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Sistema Nervoso Central , Cefaleia , Neoplasias Meníngeas/cirurgia , Meningioma/cirurgia
12.
Artigo em Inglês | MEDLINE | ID: mdl-38222104

RESUMO

Fitting penalized models for the purpose of merging the estimation and model selection problem has become commonplace in statistical practice. Of the various regularization strategies that can be leveraged to this end, the use of the l0 norm to penalize parameter estimation poses the most daunting model fitting task. In fact, this particular strategy requires an end user to solve a non-convex NP-hard optimization problem irregardless of the underlying data model. For this reason, the use of the l0 norm as a regularization strategy has been woefully under utilized. To obviate this difficulty, a strategy to solve such problems that is generally accessible by the statistical community is developed. The approach can be adopted to solve l0 norm penalized problems across a very broad class of models, can be implemented using existing software, and is computationally efficient. The performance of the method is demonstrated through in-depth numerical experiments and through using it to analyze several prototypical data sets.

13.
Sensors (Basel) ; 24(2)2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38276343

RESUMO

Participatory crowdsensing (PCS) is an innovative data sensing paradigm that leverages the sensors carried in mobile devices to collect large-scale environmental information and personal behavioral data with the user's participation. In PCS, task assignment and path planning pose complex challenges. Previous studies have only focused on the assignment of individual tasks, neglecting or overlooking the associations between tasks. In practice, users often tend to execute similar tasks when choosing assignments. Additionally, users frequently engage in tasks that do not match their abilities, leading to poor task quality or resource wastage. This paper introduces a multi-task assignment and path-planning problem (MTAPP), which defines utility as the ratio of a user's profit to the time spent on task execution. The optimization goal of MATPP is to maximize the utility of all users in the context of task assignment, allocate a set of task locations to a group of workers, and generate execution paths. To solve the MATPP, this study proposes a grade-matching degree and similarity-based mechanism (GSBM) in which the grade-matching degree determines the user's income. It also establishes a mathematical model, based on similarity, to investigate the impact of task similarity on user task completion. Finally, an improved ant colony optimization (IACO) algorithm, combining the ant colony and greedy algorithms, is employed to maximize total utility. The simulation results demonstrate its superior performance in terms of task coverage, average task completion rate, user profits, and task assignment rationality compared to other algorithms.

14.
Radiol Med ; 129(2): 239-251, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38214839

RESUMO

BACKGROUND: This study aimed to develop and validate radiomics and deep learning (DL) signatures for predicting distal metastasis (DM) of non-small cell lung cancer (NSCLC) in low-dose computed tomography (LDCT). METHODS: Images and clinical data were retrospectively collected for 381 NSCLC patients and prospectively collected for 114 patients at the Fifth Affiliated Hospital of Sun Yat-Sen University. Additionally, we enrolled 179 patients from the Jiangmen Central Hospital to externally validate the signatures. Machine-learning algorithms were employed to develop radiomics signature while the DL signature was developed using neural architecture search. The diagnostic efficiency was primarily quantified with the area under receiver operating characteristic curve (AUC). We interpreted the reasoning process of the radiomics signature and DL signature by radiomics voxel mapping and attention weight tracking. RESULTS: A total of 674 patients with pathologically-confirmed NSCLC were included from two institutions, with 143 of them having DM. The radiomics signature achieved AUCs of 0.885, 0.854, and 0.733 in the internal validation, prospective validation, and external validation while those for DL signature were 0.893, 0.786, and 0.780. The proposed signatures achieved a promising performance in predicting the DM of NSCLC and outperformed the approaches proposed in previous studies. Interpretability analysis revealed that both radiomics and DL signatures could detect the variations among voxels inside tumors, which helped in identifying the DM of NSCLC. CONCLUSIONS: Our study demonstrates the potential of LDCT-based radiomics and DL signatures for predicting DM in NSCLC. These signatures could help improve lung cancer screening regarding further diagnostic tests and treatment strategies.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Aprendizado Profundo , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Estudos Retrospectivos , Detecção Precoce de Câncer , Radiômica , Tomografia Computadorizada por Raios X/métodos , Computadores
15.
Angew Chem Int Ed Engl ; 63(17): e202318568, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38433368

RESUMO

ATR has emerged as a promising target for anti-cancer drug development. Several potent ATR inhibitors are currently undergoing various stages of clinical trials, but none have yet received FDA approval due to unclear regulatory mechanisms. In this study, we discovered a potent and selective ATR degrader. Its kinase-independent regulatory functions in acute myeloid leukemia (AML) cells were elucidated using this proteolysis-targeting chimera (PROTAC) molecule as a probe. The ATR degrader, 8 i, exhibited significantly different cellular phenotypes compared to the ATR kinase inhibitor 1. Mechanistic studies revealed that ATR deletion led to breakdown in the nuclear envelope, causing genome instability and extensive DNA damage. This would increase the expression of p53 and triggered immediately p53-mediated apoptosis signaling pathway, which was earlier and more effective than ATR kinase inhibition. Based on these findings, the in vivo anti-proliferative effects of ATR degrader 8 i were assessed using xenograft models. The degrader significantly inhibited the growth of AML cells in vivo, unlike the ATR inhibitor. These results suggest that the marked anti-AML activity is regulated by the kinase-independent functions of the ATR protein. Consequently, developing potent and selective ATR degraders could be a promising strategy for treating AML.


Assuntos
Antineoplásicos , Leucemia Mieloide Aguda , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteínas Mutadas de Ataxia Telangiectasia/uso terapêutico , Linhagem Celular Tumoral , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/metabolismo , Proteólise , Proteína Supressora de Tumor p53/metabolismo
16.
Neuroimage ; 283: 120426, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37898378

RESUMO

The level of consciousness undergoes continuous alterations during anesthesia. Prior to the onset of propofol-induced complete unconsciousness, degraded levels of behavioral responsiveness can be observed. However, a reliable index to monitor altered consciousness levels during anesthesia has not been sufficiently investigated. In this study, we obtained 60-channel EEG data from 24 healthy participants during an ultra-slow propofol infusion protocol starting with an initial concentration of 1 µg/ml and a stepwise increase of 0.2 µg/ml in concentration. Consecutive auditory stimuli were delivered every 5 to 6 s, and the response time to the stimuli was used to assess the responsiveness levels. We calculated the spectral slope in a time-resolved manner by extracting 5-second EEG segments at each auditory stimulus and estimated their correlation with the corresponding response time. Our results demonstrated that during slow propofol infusion, the response time to external stimuli increased, while the EEG spectral slope, fitted at 15-45 Hz, became steeper, and a significant negative correlation was observed between them. Moreover, the spectral slope further steepened at deeper anesthetic levels and became flatter during anesthesia recovery. We verified these findings using an external dataset. Additionally, we found that the spectral slope of frontal electrodes over the prefrontal lobe had the best performance in predicting the response time. Overall, this study used a time-resolved analysis to suggest that the EEG spectral slope could reliably track continuously altered consciousness levels during propofol anesthesia. Furthermore, the frontal spectral slope may be a promising index for clinical monitoring of anesthesia depth.


Assuntos
Anestesia , Propofol , Humanos , Propofol/farmacologia , Estado de Consciência/fisiologia , Eletroencefalografia , Inconsciência/induzido quimicamente , Anestésicos Intravenosos/farmacologia
17.
Cancer Sci ; 114(6): 2569-2583, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36880750

RESUMO

The clinical outcome of resectable non-small-cell lung cancer (NSCLC) patients receiving neoadjuvant chemoimmunotherapy is good but varies greatly. In addition, the pathological response after neoadjuvant chemoimmunotherapy is significantly associated with survival outcomes. The aim of this retrospective study was to identify which population of patients with locally advanced and oligometastatic NSCLC has a favorable pathological response after neoadjuvant chemoimmunotherapy. NSCLC patients treated with neoadjuvant chemoimmunotherapy were enrolled between February 2018 and April 2022. Data on clinicopathological features were collected and evaluated. Multiplex immunofluorescence was performed on pre-treatment puncture specimens and surgically resected specimens. In total, 29 patients with stages III and IV locally advanced or oligometastatic NSCLC who received neoadjuvant chemoimmunotherapy and R0 resection were enrolled. The results showed that 55% (16/29) of patients had a major pathological response (MPR) and 41% (12/29) of patients had a complete pathological response (pCR). In the stroma area of the pre-treatment specimen, the higher infiltration of CD3+ PD-L1+ tumor-infiltrating lymphocytes (TILs) and the lower infiltration of CD4+ and CD4+ FOXP3+ TILs were more likely to appear in patients with pCR. However, in the tumor area, the higher infiltration of CD8+ TILs was more likely to appear in patients with non-MPR. In the post-treatment specimen, we found increased infiltration of CD3+ CD8+ , CD8+ GZMB+ , and CD8+ CD69+ TILs and decreased infiltration of PD-1+ TILs both in the stroma and tumor areas. Neoadjuvant chemoimmunotherapy achieved an MPR rate of 55% and induced greater immune infiltration. In addition, we observed that the baseline TILs and their spatial distribution correlate to the pathological response.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Terapia Neoadjuvante , Estudos Retrospectivos , Microambiente Tumoral , Linfócitos do Interstício Tumoral , Antígeno B7-H1
18.
Plant Biotechnol J ; 21(9): 1873-1886, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37323119

RESUMO

Salicylic acid (SA) is an essential plant hormone that plays critical roles in basal defence and amplification of local immune responses and establishes resistance against various pathogens. However, the comprehensive knowledge of the salicylic acid 5-hydroxylase (S5H) in rice-pathogen interaction is still elusive. Here, we reported that three OsS5H homologues displayed salicylic acid 5-hydroxylase activity, converting SA into 2,5-dihydroxybenzoic acid (2,5-DHBA). OsS5H1, OsS5H2, and OsS5H3 were preferentially expressed in rice leaves at heading stage and responded quickly to exogenous SA treatment. We found that bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo) strongly induced the expression of OsS5H1, OsS5H2, and OsS5H3. Rice plants overexpressing OsS5H1, OsS5H2, and OsS5H3 showed significantly decreased SA contents and increased 2,5-DHBA levels, and were more susceptible to bacterial blight and rice blast. A simple single guide RNA (sgRNA) was designed to create oss5h1oss5h2oss5h3 triple mutants through CRISPR/Cas9-mediated gene mutagenesis. The oss5h1oss5h2oss5h3 exhibited stronger resistance to Xoo than single oss5h mutants. And oss5h1oss5h2oss5h3 plants displayed enhanced rice blast resistance. The conferred pathogen resistance in oss5h1oss5h2oss5h3 was attributed to the significantly upregulation of OsWRKY45 and pathogenesis-related (PR) genes. Besides, flg22-induced reactive oxygen species (ROS) burst was enhanced in oss5h1oss5h2oss5h3. Collectively, our study provides a fast and effective approach to generate rice varieties with broad-spectrum disease resistance through OsS5H gene editing.


Assuntos
Oryza , Xanthomonas , Resistência à Doença/genética , Sistemas CRISPR-Cas , RNA Guia de Sistemas CRISPR-Cas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Ácido Salicílico/farmacologia , Ácido Salicílico/metabolismo , Mutação/genética , Oryza/metabolismo , Doenças das Plantas/microbiologia , Regulação da Expressão Gênica de Plantas
19.
Opt Express ; 31(21): 33923-33929, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37859161

RESUMO

UV and visible photonics enable applications ranging from spectroscopic sensing to communication and quantum information processing. Photonics structures in these wavelength regimes, however, tend to experience higher loss than their IR counterpart. Particularly in the near-UV band, on-chip optical microresonators have not yet achieved a quality factor beyond 1 million. Here, we report ultra-low-loss photonic waveguides and resonators patterned from alumina thin films prepared by a highly scalable atomic layer deposition process. We demonstrate ultra high Q factor of 1.5×106 at 390 nm, a record value at UV bands, and 1.9×106 at 488.5 nm.

20.
J Nutr ; 153(11): 3207-3219, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37696395

RESUMO

BACKGROUND: Lauric acid (LA), a major, natural, medium-chain fatty acid, is considered an efficient energy substrate for intense exercise and in patients with long-chain fatty acid ß-oxidation disorders. However, few studies have focused on the role of LA in exercise performance and related glucolipid metabolism in vivo. OBJECTIVES: We aimed to investigate the effect of dietary supplementation with LA on exercise performance and related metabolic mechanisms. METHODS: Male C57BL/6N mice (14 wk old) were fed a basal diet or a diet containing 1% LA, and a series of exercise tests, including a high-speed treadmill test, aerobic endurance exercises, a 4-limb hanging test, and acute aerobic exercises, were performed. RESULTS: Dietary supplementation with 1.0% LA accelerated the recovery from fatigue after explosive exercise (P < 0.05) and improved aerobic endurance and muscle strength in sedentary mice (P = 0.039). Lauric acid intake not only changed muscle fatty acid profiles, including increases in C12:0 and n-6/n-3 PUFAs (P < 0.001) and reductions in C18:0, C20:4n-6, C22:6n-3, and n-3 PUFAs (P < 0.05) but also enhanced fat mobilization from adipose tissue and fatty acid oxidation in the liver, at least partly via the AMP-activated protein kinase-acetyl CoA carboxylase pathway (P < 0.05). Likewise, LA supplementation promoted liver glyconeogenesis and conserved muscular glycogen during acute aerobic exercise (P < 0.05), which was accompanied by an increase in the mitochondrial DNA copy number and Krebs cycle activity in skeletal muscle (P < 0.05). CONCLUSIONS: Dietary supplemental LA serves as an efficient energy substrate for sedentary mice to improve aerobic exercise endurance and muscle strength through regulation of glucolipid metabolism. These findings imply that LA supplementation might be a promising nutritional strategy to improve aerobic exercise performance in sedentary people.


Assuntos
Suplementos Nutricionais , Músculo Esquelético , Humanos , Masculino , Camundongos , Animais , Camundongos Endogâmicos C57BL , Tecido Adiposo/metabolismo , Ácidos Graxos/metabolismo , Resistência Física
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