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1.
Front Immunol ; 15: 1362133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38558812

RESUMO

Chimeric antigen receptor (CAR) -T cell therapy has achieved tremendous efficacy in the treatment of hematologic malignancies and represents a promising treatment regimen for cancer. Despite the striking response in patients with hematologic malignancies, most patients with solid tumors treated with CAR-T cells have a low response rate and experience major adverse effects, which indicates the need for biomarkers that can predict and improve clinical outcomes with future CAR-T cell treatments. Recently, the role of the gut microbiota in cancer therapy has been established, and growing evidence has suggested that gut microbiota signatures may be harnessed to personally predict therapeutic response or adverse effects in optimizing CAR-T cell therapy. In this review, we discuss current understanding of CAR-T cell therapy and the gut microbiota, and the interplay between the gut microbiota and CAR-T cell therapy. Above all, we highlight potential strategies and challenges in harnessing the gut microbiota as a predictor and modifier of CAR-T cell therapy efficacy while attenuating toxicity.


Assuntos
Microbioma Gastrointestinal , Neoplasias Hematológicas , Neoplasias , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T , Neoplasias/terapia , Neoplasias Hematológicas/terapia , Terapia Baseada em Transplante de Células e Tecidos
2.
World J Gastroenterol ; 30(9): 1164-1176, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38577177

RESUMO

BACKGROUND: Diffusion-weighted imaging (DWI) has been developed to stage liver fibrosis. However, its diagnostic performance is inconsistent among studies. Therefore, it is worth studying the diagnostic value of various diffusion models for liver fibrosis in one cohort. AIM: To evaluate the clinical potential of six diffusion-weighted models in liver fibrosis staging and compare their diagnostic performances. METHODS: This prospective study enrolled 59 patients suspected of liver disease and scheduled for liver biopsy and 17 healthy participants. All participants underwent multi-b value DWI. The main DWI-derived parameters included Mono-apparent diffusion coefficient (ADC) from mono-exponential DWI, intravoxel incoherent motion model-derived true diffusion coefficient (IVIM-D), diffusion kurtosis imaging-derived apparent diffusivity (DKI-MD), stretched exponential model-derived distributed diffusion coefficient (SEM-DDC), fractional order calculus (FROC) model-derived diffusion coefficient (FROC-D) and FROC model-derived microstructural quantity (FROC-µ), and continuous-time random-walk (CTRW) model-derived anomalous diffusion coefficient (CTRW-D) and CTRW model-derived temporal diffusion heterogeneity index (CTRW-α). The correlations between DWI-derived parameters and fibrosis stages and the parameters' diagnostic efficacy in detecting significant fibrosis (SF) were assessed and compared. RESULTS: CTRW-D (r = -0.356), CTRW-α (r = -0.297), DKI-MD (r = -0.297), FROC-D (r = -0.350), FROC-µ (r = -0.321), IVIM-D (r = -0.251), Mono-ADC (r = -0.362), and SEM-DDC (r = -0.263) were significantly correlated with fibrosis stages. The areas under the ROC curves (AUCs) of the combined index of the six models for distinguishing SF (0.697-0.747) were higher than each of the parameters alone (0.524-0.719). The DWI models' ability to detect SF was similar. The combined index of CTRW model parameters had the highest AUC (0.747). CONCLUSION: The DWI models were similarly valuable in distinguishing SF in patients with liver disease. The combined index of CTRW parameters had the highest AUC.


Assuntos
Imagem de Difusão por Ressonância Magnética , Hepatopatias , Humanos , Estudos Prospectivos , Imagem de Difusão por Ressonância Magnética/métodos , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Imagem de Tensor de Difusão/métodos
4.
Chemistry ; 30(16): e202304372, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38191767

RESUMO

Incorporating heteroatoms can effectively modulate the molecular optoelectronic properties. However, the fundamental understanding of BN doping effects in BN-embedded polycyclic aromatic hydrocarbons (PAHs) is underexplored, lacking rational guidelines to modulate the electronic structures through BN units for advanced materials. Herein, a concise synthesis of novel B2N2-perylenes with BN doped at the bay area is achieved to systematically explore the doping effect of BN position on the photophysical properties of PAHs. The shift of BN position in B2N2-perylenes alters the π electron conjugation, aromaticity and molecular rigidness significantly, achieving substantially higher electron transition abilities than those with BN doped in the nodal plane. It is further clarified that BN position dominates the photophysical properties over BN orientation. The revealed guideline here may apply generally to novel BN-PAHs, and aid the advancement of BN-PAHs with highly-emissive performance.

5.
Nat Commun ; 15(1): 621, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245530

RESUMO

Intratumoral immune status influences tumor therapeutic response, but it remains largely unclear how the status determines therapies for patients with intrahepatic cholangiocarcinoma. Here, we examine the single-cell transcriptional and TCR profiles of 18 tumor tissues pre- and post- therapy of gemcitabine plus oxaliplatin, in combination with lenvatinib and anti-PD1 antibody for intrahepatic cholangiocarcinoma. We find that high CD8 GZMB+ and CD8 proliferating proportions and a low Macro CD5L+ proportion predict good response to the therapy. In patients with a poor response, the CD8 GZMB+ and CD8 proliferating proportions are increased, but the CD8 GZMK+ proportion is decreased after the therapy. Transition of CD8 proliferating and CD8 GZMB+ to CD8 GZMK+ facilitates good response to the therapy, while Macro CD5L+-CD8 GZMB+ crosstalk impairs the response by increasing CTLA4 in CD8 GZMB+. Anti-CTLA4 antibody reverses resistance of the therapy in intrahepatic cholangiocarcinoma. Our data provide a resource for predicting response of the combination therapy and highlight the importance of CD8+T-cell status conversion and exhaustion induced by Macro CD5L+ in influencing the response, suggesting future avenues for cancer treatment optimization.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Compostos de Fenilureia , Quinolinas , Humanos , Oxaliplatina/uso terapêutico , Gencitabina , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Linfócitos T CD8-Positivos , Ductos Biliares Intra-Hepáticos , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/patologia , Proteínas Reguladoras de Apoptose , Receptores Depuradores
6.
Ecol Evol ; 14(1): e10848, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38264336

RESUMO

Many kinds of medicinal ingredients occur in Cirsium lineare that have good clinical efficacy, conferring on this species its high medicinal development value. However, with a rapidly changing global climate, it is increasingly imperative to study the factors affecting the habitat distribution and survival of species. We predicted the current and future distribution areas of suitable habitats for C. lineare, analyzed the importance of environmental variables in influencing habitat shifts, and described the alterations to suitable habitats of C. lineare in different periods (modern, 2050s, and 2070s) and scenarios (RCP2.6, RCP4.5, and RCP8.5). The results show that, under the current climate, the total suitable area of C. lineare is about 2,220,900 km2, of which the highly suitable portion amounts to ca. 292,600 km2. The minimum temperature of the coldest month, annual precipitation, and mean daily temperature range are the chief environmental variables affecting the distribution of habitat for C. lineare. In the same period, with rising greenhouse gas emission concentrations, the total suitable area will increase. In general, under future climate change, the suitable habitat for C. lineare will gradually migrate to the west and north, and its total suitable area will also expand. The results of this experiment can be used for the conservation and management of the wild resources of C. lineare. We can choose suitable growth areas to protect the medicinal resources of C. lineare through in situ conservation and artificial breeding.

7.
Small ; : e2306010, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37884476

RESUMO

Realizing ideal charge transport in field-effect transistors (FETs) of conjugated polymers is crucial for evaluating device performance, such as carrier mobility and practical applications of conjugated polymers. However, the current FETs using conjugated polymers as the active layers generally show certain non-ideal transport characteristics and poor stability. Here, ideal charge transport of n-type polymer FETs is achieved on flexible polyimide substrates by using an organic-inorganic hybrid double-layer dielectric. Deposited conjugated polymer films show highly ordered structures and low disorder, which are supported by grazing-incidence wide-angle X-ray scattering, near-edge X-ray absorption fine structure, and molecular dynamics simulations. Furthermore, the organic-inorganic hybrid double-layer dielectric provides low interfacial defects, leading to excellent charge transport in FETs with high electron mobility (1.49 ± 0.46 cm2  V-1  s-1 ) and ideal reliability factors (102 ± 7%). Fabricated polymer FETs show a self-encapsulation effect, resulting in high stability of the FET charge transport. The polymer FETs still work with high mobility above 1 cm2  V-1  s-1 after storage in air for more than 300 days. Compared with state-of-the-art conjugated polymer FETs, this work simultaneously achieves ideal charge transport and environmental stability in n-type polymer FETs, facilitating rapid device optimization of high-performance polymer electronics.

8.
Cost Eff Resour Alloc ; 21(1): 65, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37705023

RESUMO

BACKGROUND: The aim of the study was to evaluate the cost-effectiveness of nivolumab plus chemotherapy as first-line treatment for patients with advanced gastric, gastroesophageal junction (GEJ), or esophageal adenocarcinoma from the perspective of Chinese and US society. METHODS: To conduct the analysis, a state-transitioned Markov model, which included three mutually exclusive health states (progression-free survival (PFS), progressive disease (PD), and death), was developed. Cycle length was set at 3 weeks and lifetime horizon was set at 10 years. Costs, quality-adjusted life years (QALYs), and incremental cost-effectiveness ratio (ICER) were calculated in the analysis. Willingness-to-pay (WTP) thresholds in the model were set at $37,653.00/QALY in China and $100,000.00/QALY in the US, respectively. Meanwhile, one-way sensitivity analyses and probabilistic sensitivity analyses were conducted to investigate the robustness of the model. RESULTS: Over a lifetime horizon, the ICERs of nivolumab plus chemotherapy versus chemotherapy alone were $430,185.04/QALY and $944,089.78/QALY in China and the US, respectively. Cost of nivolumab and utility for the PFS state had the most significant impact on ICERs both in the US and China based on the results of the one-way sensitivity analyses. In the probabilistic sensitivity analyses, the proportions of nivolumab plus chemotherapy being cost-effective compared with chemotherapy alone were 0%. CONCLUSIONS: In conclusion, nivolumab plus chemotherapy is unlikely to be a cost-effective treatment option compared with chemotherapy alone in the first-line setting of advanced gastric, GEJ, or esophageal adenocarcinoma.

9.
Quant Imaging Med Surg ; 13(7): 4563-4577, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37456330

RESUMO

Background: Myocardial work (MW) indices and longitudinal strain (LS) are sensitive markers of early left ventricular systolic dysfunction. Stress computed tomography myocardial perfusion imaging (CT-MPI) can assess early myocardial ischemia. The association between resting MW indices and stress myocardial perfusion remains unclear. This study compares resting MW indices with LS to assess stress myocardial perfusion in angina patients with non-obstructive coronary artery disease (CAD). Methods: Eighty-four patients who underwent resting echocardiography, coronary computed tomography angiography, and stress CT-MPI were reviewed. Seventeen myocardial segments were divided into three regions according to the epicardial coronary arteries. Global indices included global longitudinal strain (GLS), global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE). Regional indices included regional longitudinal strain (RLS), regional work index (RWI), and regional work efficiency (RWE). Reduced global perfusion was defined as an average stress myocardial blood flow (MBF) <116 mL/100 mL/min for the whole heart. Reduced regional perfusion was defined as an average stress MBF <116 mL/100 mL/min for the coronary territories. No patients demonstrated obstructions in the epicardial coronary arteries (stenosis diameter <50%). The MW indices and LS were compared. Receiver operating characteristic curves were constructed and logistic regression analyses were used to investigate the predictors of reduced myocardial perfusion. Results: Patients with reduced stress perfusion demonstrated reduced GLS, GWI, GCW, and GWE (P<0.05) and increased GWW (P<0.05). After adjustment for age and sex, GWE was still independently associated with reduced myocardial perfusion (odds ratio =0.386, 95% confidence interval: 0.214-0.697; P<0.05). Receiver operating characteristic curves reflected the good diagnostic ability of GWE and its superiority to GLS (area under the curve: 0.858 vs. 0.741). The optimal cutoff GWE value was 95% (sensitivity, 70%; specificity, 90%). Regions with lower stress perfusion showed lower RLS, RWI, and RWE (P<0.05). The optimal cutoff value of RWE for predicting reduced regional perfusion was 95%, with an area under the curve of 0.780, a sensitivity of 62%, and a specificity of 83%. Conclusions: Resting MW indices perform well in assessing global and regional stress myocardial perfusion in angina patients with non-obstructive CAD, and GWE is superior to GLS in the global evaluations.

10.
Org Biomol Chem ; 21(31): 6307-6311, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37492010

RESUMO

A new method has been successfully developed that offers a facile and reliable approach for synthesizing (E)-2-(1-(methoxyimino)ethyl)-2-phenylbenzofuran-3(2H)-one, providing 28 compounds. This optimized process enables efficient preparation of a wide range of compounds using readily available (E)-1-(benzofuran-2-yl)ethan-1-one O-methyl oxime and iodobenzene, and provides alternative ideas for the structural modification of benzofuran ketones.

11.
J Geriatr Cardiol ; 20(6): 469-478, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37416517

RESUMO

BACKGROUND: The efficiency of the target versus sub-target dose of renin-angiotensin system inhibitors (RASIs) in elderly patients with heart failure (HF) with reduced ejection fraction (HErEF) remains unclear. METHODS: PubMed, Embase, and the Cochrane Central Register of Controlled Trials were searched from database inception through March 2022 for randomized controlled trials (RCTs) and observational studies considering the effect of the target versus sub-target dose of RASIs on survival in elderly patients (≥ 60 years) with HErEF. The primary outcome was all-cause mortality. The secondary outcomes were cardiac mortality, HF hospitalization, and the composite endpoint of mortality or HF hospitalization. A meta-analysis was conducted to generate combined hazard ratio (HR) and 95% CI. RESULTS: Seven studies (two RCTs and five observational studies) enrolling 16,634 patients were included. A pooled analysis suggested that the target versus sub-target dose of RASIs led to lower rates of all-cause mortality (HR = 0.92, 95% CI: 0.87-0.98, I2 = 21%) and cardiac mortality (HR = 0.93, 95% CI: 0.85-1.00, I2 = 15%) but not reduced rates of HF hospitalization (HR = 0.94, 95% CI: 0.88-1.01, I2 = 0) and the composite endpoint (HR = 1.03, 95% CI: 0.91-1.15, I2 = 51%). However, the target dose of RASIs was associated with a similar primary outcome (HR = 0.85, 95% CI: 0.64-1.14, I2 = 0) in a subgroup of very elderly patients > 75 years of age. CONCLUSIONS: Our analysis suggests that the target dose of RASIs has a better survival benefit in elderly patients with HFrEF compared to the sub-target dose of RASIs. However, the sub-target dose of RASIs is associated with a similar mortality rate in very elderly patients > 75 years of age. Future high-quality and adequately powered RCTs are warranted.

12.
Heliyon ; 9(5): e16161, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37234672

RESUMO

Objective: The aim of this study was to assess the effect of flap design for impacted mandibular third molar extraction on the distal periodontal tissue of their neighbors clinically, immunologically, and microbiologically. Study design: This randomized controlled study comprised 100 patients who were allocated randomly to receive either a triangular flap or a modified triangular flap. The distal periodontal pocket depth, plaque index, bleeding on probing, the presence of Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis and Prevotella intermedia, and the level of interleukin-1ß, interleukin-8 and matrix metalloproteinase-8 of adjacent second molars were measured at baseline, and 1, 4 and 8 weeks after surgery. Results: After 1 and 4 weeks, distal periodontal conditions of adjacent second molars deteriorated, along with an increase in subgingival microbiota and inflammatory factors in both groups. And compared to the modified triangular flap group, the triangular flap group significantly increased (p < 0.05). Prevotella intermedia, interleukin-1ß and probing depth were positively correlated in both groups. After 8 weeks, they returned to the preoperative level. Conclusions: In this study, both flap designs for impacted mandibular third molar extractions was associated with worse clinical periodontal indices, increased inflammatory biomarkers of gingival crevicular fluid, and more subgingival pathogenic microbiota within 4 weeks. But compared with the triangular flap, the modified triangular flap was better for distal periodontal health of adjacent second molars, which provides certain directions for clinical treatment.

14.
J Cancer Res Clin Oncol ; 149(11): 8631-8638, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37099198

RESUMO

PURPOSE: Cannabis use is increasing legally worldwide, while its impact on cancer risk is unclear. This study was performed to investigate the relationship between cannabis use and the risk of several types of cancer. METHODS: We conducted a two-sample Mendelian randomization (MR) study to explore the causality of cannabis use on 9 site-specific types of cancer including breast cancer, cervical cancer, melanoma, colorectal cancer, laryngeal cancer, oral cancer, oropharyngeal cancer, esophageal cancer, and glioma. Genome-wide significant genetic instruments (P < 5E-06) for cannabis use were extracted from a large-scale genome-wide association meta-analysis of European ancestry, whereas cancer genetic instruments were extracted from the UK Biobank (UKB) cohort and GliomaScan consortium in the OpenGWAS database. The inverse-variance weighted (IVW) was considered the main method for MR analysis, and sensitivity analyses including MR-Egger, weighted median, MR pleiotropy residual sum, and outlier test (MR-PRESSO) were conducted to evaluate the robustness of the results. RESULTS: Cannabis use was a significant promoting factor for cervical cancer (OR = 1.001265, 95% CI 1.000375-1.002155, P = 0.0053). And we also detected suggestive evidence of the causality of cannabis use on laryngeal cancer (OR = 1.000350, 95% CI 1.000027-1.000672, P = 0.0336) and breast cancer (OR = 1.003741, 95% CI 1.000052-1.007442, P = 0.0467). No evidence of a causal association of cannabis use with other site-specific types of cancer was detected. Additionally, no pleiotropy or heterogeneity was found in the sensitivity analysis. CONCLUSION: This study indicates a causative association of cannabis use on cervical cancer, while cannabis use may increase the odds of breast cancer and laryngeal cancer, which require further evaluation in large-scale population-based studies.


Assuntos
Neoplasias da Mama , Cannabis , Neoplasias Laríngeas , Neoplasias do Colo do Útero , Humanos , Feminino , Cannabis/efeitos adversos , Neoplasias Laríngeas/etiologia , Neoplasias Laríngeas/genética , Estudo de Associação Genômica Ampla , Neoplasias da Mama/etiologia , Neoplasias da Mama/genética , Polimorfismo de Nucleotídeo Único
15.
Ying Yong Sheng Tai Xue Bao ; 34(4): 1009-1014, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37078320

RESUMO

To evaluate the effects of nitrogen (N) application rates on the growth, photosynthetic traits and yield of winter wheat under elevated atmospheric ammonia (NH3) concentrations could provide guidance for N management under high NH3 environment. We conducted a split-plot experiment for two consecutive years (2020-2021 and 2021-2022) with top-open chambers. The treatments included two NH3 concentrations [elevated ambient NH3 concentration at 0.30-0.60 mg·m-3 (EAM) and air NH3 concentration at 0.01-0.03 mg·m-3 (AM)] and two N application rates [recommended N dose (+N) and no N application (-N)]. We analyzed the effects of aforementioned treatments on net photosynthetic rate (Pn), stomatal conductance (gs), chlorophyll content (SPAD value), plant height, and grain yield. The results showed that averaged across the two years, EAM significantly increased Pn, gs, and SPAD values at the jointing and booting stages at the -N level by 24.6%, 16.3%, 21.9% and 20.9%, 37.1%, 5.7%, respectively, compared with AM. However, EAM significantly decreased Pn, gs, and SPAD values at jointing and booting stages at +N level by 10.8%, 5.9%, 3.6% and 6.8%, 18.9%, 9.3%, respectively, over AM treatment. There was a significant effect of NH3 treatment, N application rates and their interaction on plant height and grain yield. Compared with AM, EAM increased the average plant height and grain yield by 4.5% and 32.1% at -N level and decreased by 1.1% and 8.5% at +N level, respectively. In a nutshell, the eleva-ted ambient NH3 concentration had positive effect on photosynthetic characteristics, plant height, and grain yield under ambient N condition, but a inhibitory effect under N application.


Assuntos
Amônia , Triticum , Nitrogênio/farmacologia , Folhas de Planta , Fertilizantes , Fotossíntese , Grão Comestível
16.
Sheng Li Xue Bao ; 75(2): 171-178, 2023 Apr 25.
Artigo em Chinês | MEDLINE | ID: mdl-37089091

RESUMO

The aim of the present study was to investigate the effects of short-term ketogenic diet on the low temperature tolerance of mice and the involvement of peroxisome proliferator-activated receptor α (PPARα). C57BL/6J mice were divided into two groups: normal diet (WT+ND) group and ketogenic diet (WT+KD) group. After being fed with normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The changes in core temperature, blood glucose, blood pressure of mice under low temperature condition were detected, and the protein expression levels of PPARα and mitochondrial uncoupling protein 1 (UCP1) were detected by Western blot. PPARα knockout mice were divided into normal diet (PPARα-/-+ND) group and ketogenic diet (PPARα-/-+KD) group. After being fed with the normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The above indicators were also detected. The results showed that, at room temperature, the protein expression levels of PPARα and UCP1 in liver and brown adipose tissue of WT+KD group were significantly up-regulated, compared with those of WT+ND group. Under low temperature condition, compared with WT+ND, the core temperature and blood glucose of WT+KD group were increased, while mean arterial pressure was decreased; The ketogenic diet up-regulated PPARα protein expression in brown adipose tissue, as well as UCP1 protein expression in liver and brown adipose tissue of WT+KD group. Under low temperature condition, compared to WT+ND group, PPARα-/-+ND group exhibited decreased core temperature and down-regulated PPARα and UCP1 protein expression levels in liver, skeletal muscle, white and brown adipose tissue. Compared to the PPARα-/-+ND group, the PPARα-/-+KD group exhibited decreased core temperature and did not show any difference in the protein expression of UCP1 in liver, skeletal muscle, white and brown adipose tissue. These results suggest that the ketogenic diet promotes UCP1 expression by up-regulating PPARα, thus improving low temperature tolerance of mice. Therefore, short-term ketogenic diet can be used as a potential intervention to improve the low temperature tolerance.


Assuntos
Tecido Adiposo Marrom , Dieta Cetogênica , Animais , Camundongos , Tecido Adiposo Marrom/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , PPAR alfa/farmacologia , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo , Glicemia/metabolismo , Temperatura , Camundongos Endogâmicos C57BL , Fígado , Tecido Adiposo/metabolismo
17.
Front Chem ; 11: 1166593, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37090248

RESUMO

Water, in trace amounts, can greatly alter chemical and physical properties of mantle minerals and exert primary control on Earth's dynamics. Quantifying how water is retained and distributed in Earth's deep interior is essential to our understanding of Earth's origin and evolution. While directly sampling Earth's deep interior remains challenging, the experimental technique using laser-heated diamond anvil cell (LH-DAC) is likely the only method available to synthesize and recover analog specimens throughout Earth's lower mantle conditions. The recovered samples, however, are typically of micron sizes and require high spatial resolution to analyze their water abundance. Here we use nano-scale secondary ion mass spectrometry (NanoSIMS) to characterize water content in bridgmanite, the most abundant mineral in Earth's lower mantle. We have established two working standards of natural orthopyroxene that are likely suitable for calibrating water concentration in bridgmanite, i.e., A119(H2O) = 99 ± 13 µg/g (1SD) and A158(H2O) = 293 ± 23 µg/g (1SD). We find that matrix effect among orthopyroxene, olivine, and glass is less than 10%, while that between orthopyroxene and clinopyroxene can be up to 20%. Using our calibration, a bridgmanite synthesized by LH-DAC at 33 ± 1 GPa and 3,690 ± 120 K is measured to contain 1,099 ± 14 µg/g water, with partition coefficient of water between bridgmanite and silicate melt ∼0.025, providing the first measurement at such condition. Applying the unique analytical capability of NanoSIMS to minute samples recovered from LH-DAC opens a new window to probe water and other volatiles in Earth's deep mantle.

18.
Nature ; 615(7950): 56-61, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36859579

RESUMO

Correlating atomic configurations-specifically, degree of disorder (DOD)-of an amorphous solid with properties is a long-standing riddle in materials science and condensed matter physics, owing to difficulties in determining precise atomic positions in 3D structures1-5. To this end, 2D systems provide insight to the puzzle by allowing straightforward imaging of all atoms6,7. Direct imaging of amorphous monolayer carbon (AMC) grown by laser-assisted depositions has resolved atomic configurations, supporting the modern crystallite view of vitreous solids over random network theory8. Nevertheless, a causal link between atomic-scale structures and macroscopic properties remains elusive. Here we report facile tuning of DOD and electrical conductivity in AMC films by varying growth temperatures. Specifically, the pyrolysis threshold temperature is the key to growing variable-range-hopping conductive AMC with medium-range order (MRO), whereas increasing the temperature by 25 °C results in AMC losing MRO and becoming electrically insulating, with an increase in sheet resistance of 109 times. Beyond visualizing highly distorted nanocrystallites embedded in a continuous random network, atomic-resolution electron microscopy shows the absence/presence of MRO and temperature-dependent densities of nanocrystallites, two order parameters proposed to fully describe DOD. Numerical calculations establish the conductivity diagram as a function of these two parameters, directly linking microstructures to electrical properties. Our work represents an important step towards understanding the structure-property relationship of amorphous materials at the fundamental level and paves the way to electronic devices using 2D amorphous materials.

19.
Cell Death Dis ; 14(2): 79, 2023 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-36732324

RESUMO

Multidrug resistance is a major challenge in treating advanced hepatocellular carcinoma (HCC). Although recent studies have reported that the multidrug resistance phenotype is associated with abnormal DNA methylation in cancer cells, the epigenetic mechanism underlying multidrug resistance remains unknown. Here, we reported that the level of 5-hydroxymethylcytosine (5-hmC) in human HCC tissues was significantly lower than that in adjacent liver tissues, and reduced 5-hmC significantly correlated with malignant phenotypes, including poor differentiation and microvascular invasion; additionally, loss of 5-hmC was related to chemotherapy resistance in post-transplantation HCC patients. Further, the 5-hmC level was regulated by ten-eleven translocation 2 (TET2), and the reduction of TET2 in HCC contributes to chemotherapy resistance through histone acetyltransferase P300/CBP-associated factor (PCAF) inhibition and AKT signaling hyperactivation. In conclusion, loss of 5-hmC induces chemotherapy resistance through PCAF/AKT axis and is a promising chemosensitivity prediction biomarker and therapeutic target for HCC patients.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-akt , 5-Metilcitosina
20.
BMC Genomics ; 24(1): 8, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36624393

RESUMO

BACKGROUND: Exosomes are nanosized membranous vesicles secreted by various types of cells, which facilitate intercellular communication by transporting bioactive compounds. Exosomes are abundant in biological fluids including semen, and their protein composition and the potential of seminal plasma exosomes (SPEs) as fertility biomarkers were elucidated in humans, however, little information is available regarding buffalo (Bubalus bubalis). Here, we examined protein correlation between spermatozoa, seminal plasma (SP), and SPEs, and we compared and analyzed protein differences between high-motility (H-motility) and low-motility (L-motility) SPEs in buffalo. RESULTS: SPEs were concentrated and purified by ultracentrifugation combined with sucrose density gradient centrifugation, followed by verification using western blotting, nanoparticle tracking analysis, and transmission electron microscopy. Protein composition in spermatozoa, SP and SPEs, and protein difference in H- and L-motility SPEs were identified by LC-MS/MS proteomic analysis and were functionally analyzed through comprehensive bioinformatics. Many SPEs proteins originated from spermatozoa and SP, and nearly one third were also present in spermatozoa and SP. A series of proteins associated with reproductive processes including sperm capacitation, spermatid differentiation, fertilization, sperm-egg recognition, membrane fusion, and acrosome reaction were integrated in a functional network. Comparative proteomic analyses showed 119 down-regulated and 41 up-regulated proteins in L-motility SPEs, compared with H-motility SPEs. Gene Ontology (GO) enrichment of differentially expressed proteins (DEPs) showed that most differential proteins were located in sperm and vesicles, with activities of hydrolase and metalloproteinase, and were involved in sperm-egg recognition, fertilization, single fertilization, and sperm-zona pellucida binding processes, etc. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that differential proteins were mainly involved in the PPRP signaling pathway, calcium signaling pathway, and cAMP signaling pathway, among others. Furthermore, 6 proteins associated with reproduction were validated by parallel reaction monitoring analysis. CONCLUSION: This study provides a comprehensive description of the seminal plasma exosome proteome and may be of use for further screening of biomarkers associated with male infertility.


Assuntos
Exossomos , Sêmen , Animais , Masculino , Humanos , Sêmen/metabolismo , Búfalos , Motilidade dos Espermatozoides , Cromatografia Líquida , Exossomos/metabolismo , Proteômica , Espectrometria de Massas em Tandem , Espermatozoides/metabolismo , Proteoma/metabolismo
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