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1.
Nature ; 627(8003): 281-285, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38286342

RESUMO

Tight relationships exist in the local Universe between the central stellar properties of galaxies and the mass of their supermassive black hole (SMBH)1-3. These suggest that galaxies and black holes co-evolve, with the main regulation mechanism being energetic feedback from accretion onto the black hole during its quasar phase4-6. A crucial question is how the relationship between black holes and galaxies evolves with time; a key epoch to examine this relationship is at the peaks of star formation and black hole growth 8-12 billion years ago (redshifts 1-3)7. Here we report a dynamical measurement of the mass of the black hole in a luminous quasar at a redshift of 2, with a look back in time of 11 billion years, by spatially resolving the broad-line region (BLR). We detect a 40-µas (0.31-pc) spatial offset between the red and blue photocentres of the Hα line that traces the velocity gradient of a rotating BLR. The flux and differential phase spectra are well reproduced by a thick, moderately inclined disk of gas clouds within the sphere of influence of a central black hole with a mass of 3.2 × 108 solar masses. Molecular gas data reveal a dynamical mass for the host galaxy of 6 × 1011 solar masses, which indicates an undermassive black hole accreting at a super-Eddington rate. This suggests a host galaxy that grew faster than the SMBH, indicating a delay between galaxy and black hole formation for some systems.

2.
Nature ; 581(7806): 47-52, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32376964

RESUMO

The recently discovered flat electronic bands and strongly correlated and superconducting phases in magic-angle twisted bilayer graphene (MATBG)1,2 crucially depend on the interlayer twist angle, θ. Although control of the global θ with a precision of about 0.1 degrees has been demonstrated1-7, little information is available on the distribution of the local twist angles. Here we use a nanoscale on-tip scanning superconducting quantum interference device (SQUID-on-tip)8 to obtain tomographic images of the Landau levels in the quantum Hall state9 and to map the local θ variations in hexagonal boron nitride (hBN)-encapsulated MATBG devices with relative precision better than 0.002 degrees and a spatial resolution of a few moiré periods. We find a correlation between the degree of θ disorder and the quality of the MATBG transport characteristics and show that even state-of-the-art devices-which exhibit correlated states, Landau fans and superconductivity-display considerable local variation in θ of up to 0.1 degrees, exhibiting substantial gradients and networks of jumps, and may contain areas with no local MATBG behaviour. We observe that the correlated states in MATBG are particularly fragile with respect to the twist-angle disorder. We also show that the gradients of θ generate large gate-tunable in-plane electric fields, unscreened even in the metallic regions, which profoundly alter the quantum Hall state by forming edge channels in the bulk of the sample and may affect the phase diagram of the correlated and superconducting states. We thus establish the importance of θ disorder as an unconventional type of disorder enabling the use of twist-angle gradients for bandstructure engineering, for realization of correlated phenomena and for gate-tunable built-in planar electric fields for device applications.

3.
Nature ; 582(7811): 203-208, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32528091

RESUMO

Twisted bilayer graphene near the magic angle1-4 exhibits rich electron-correlation physics, displaying insulating3-6, magnetic7,8 and superconducting phases4-6. The electronic bands of this system were predicted1,2 to narrow markedly9,10 near the magic angle, leading to a variety of possible symmetry-breaking ground states11-17. Here, using measurements of the local electronic compressibility, we show that these correlated phases originate from a high-energy state with an unusual sequence of band population. As carriers are added to the system, the four electronic 'flavours', which correspond to the spin and valley degrees of freedom, are not filled equally. Rather, they are populated through a sequence of sharp phase transitions, which appear as strong asymmetric jumps of the electronic compressibility near integer fillings of the moiré lattice. At each transition, a single spin/valley flavour takes all the carriers from its partially filled peers, 'resetting' them to the vicinity of the charge neutrality point. As a result, the Dirac-like character observed near charge neutrality reappears after each integer filling. Measurement of the in-plane magnetic field dependence of the chemical potential near filling factor one reveals a large spontaneous magnetization, further substantiating this picture of a cascade of symmetry breaking. The sequence of phase transitions and Dirac revivals is observed at temperatures well above the onset of the superconducting and correlated insulating states. This indicates that the state that we report here, with its strongly broken electronic flavour symmetry and revived Dirac-like electronic character, is important in the physics of magic-angle graphene, forming the parent state out of which the more fragile superconducting and correlated insulating ground states emerge.

4.
Ann Oncol ; 35(6): 523-536, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38408508

RESUMO

BACKGROUND: The incidence of early-onset colorectal cancer (EOCRC; diagnosed <50 years of age) is rising globally; however, the causes underlying this trend are largely unknown. CRC has strong genetic and environmental determinants, yet common genetic variants and causal modifiable risk factors underlying EOCRC are unknown. We conducted the first EOCRC-specific genome-wide association study (GWAS) and Mendelian randomization (MR) analyses to explore germline genetic and causal modifiable risk factors associated with EOCRC. PATIENTS AND METHODS: We conducted a GWAS meta-analysis of 6176 EOCRC cases and 65 829 controls from the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO), the Colorectal Transdisciplinary Study (CORECT), the Colon Cancer Family Registry (CCFR), and the UK Biobank. We then used the EOCRC GWAS to investigate 28 modifiable risk factors using two-sample MR. RESULTS: We found two novel risk loci for EOCRC at 1p34.1 and 4p15.33, which were not previously associated with CRC risk. We identified a deleterious coding variant (rs36053993, G396D) at polyposis-associated DNA repair gene MUTYH (odds ratio 1.80, 95% confidence interval 1.47-2.22) but show that most of the common genetic susceptibility was from noncoding signals enriched in epigenetic markers present in gastrointestinal tract cells. We identified new EOCRC-susceptibility genes, and in addition to pathways such as transforming growth factor (TGF) ß, suppressor of Mothers Against Decapentaplegic (SMAD), bone morphogenetic protein (BMP) and phosphatidylinositol kinase (PI3K) signaling, our study highlights a role for insulin signaling and immune/infection-related pathways in EOCRC. In our MR analyses, we found novel evidence of probable causal associations for higher levels of body size and metabolic factors-such as body fat percentage, waist circumference, waist-to-hip ratio, basal metabolic rate, and fasting insulin-higher alcohol drinking, and lower education attainment with increased EOCRC risk. CONCLUSIONS: Our novel findings indicate inherited susceptibility to EOCRC and suggest modifiable lifestyle and metabolic targets that could also be used to risk-stratify individuals for personalized screening strategies or other interventions.


Assuntos
Neoplasias Colorretais , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Adulto , Feminino , Humanos , Masculino , Idade de Início , Estudos de Casos e Controles , Neoplasias Colorretais/genética , Neoplasias Colorretais/epidemiologia , Polimorfismo de Nucleotídeo Único , Fatores de Risco
5.
Opt Express ; 32(9): 16398-16413, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38859267

RESUMO

Attosecond electron bunches have wide application prospects in free-electron laser injection, attosecond X/γ-ray generation, ultrafast physics, etc. Nowadays, there is one notable challenge in the generation of high-quality attosecond electron bunch, i.e., how to enhance the electron bunch density. Using theoretical analysis and three-dimensional particle-in-cell simulations, we discovered that a relativistic vortex laser pulse interacting with near-critical density plasma can not only effectively concentrate the attosecond electron bunches to over critical density, but also control the duration and density of the electron bunches by tuning the intensity and carrier-envelope phase of the drive laser. It is demonstrated that this method can efficiently produce attosecond electron bunches with a density up to 300 times of the original plasma density, peak divergence angle of less than 0.5 ∘, and duration of less than 67 attoseconds. Furthermore, by using near-critical density plasma instead of solid targets, our scheme is potential for the generation of high-repetition-frequency attosecond electron bunches, thus reducing the requirements for experiments, such as the beam alignment or target supporter.

6.
Phys Rev Lett ; 132(17): 176703, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38728713

RESUMO

We report the picosecond spin current generation from the interface between a heavy metal and a vicinal antiferromagnet insulator Cr_{2}O_{3} by laser pulses at room temperature and zero magnetic field. It is converted into a detectable terahertz emission in the heavy metal via the inverse spin Hall effect. The vicinal interfaces are apparently the source of the picosecond spin current, as evidenced by the proportional terahertz signals to the vicinal angle. We attribute the origin of the spin current to the transient magnetic moment generated by an interfacial nonlinear magnetic-dipole difference-frequency generation. We propose a model based on the in-plane inversion symmetry breaking to quantitatively explain the terahertz intensity with respect to the angles of the laser polarization and the film azimuth. Our work opens new opportunities in antiferromagnetic and ultrafast spintronics by considering symmetry breaking.

7.
Phys Rev Lett ; 132(24): 241801, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38949335

RESUMO

We present a first search for dark-trident scattering in a neutrino beam using a dataset corresponding to 7.2×10^{20} protons on target taken with the MicroBooNE detector at Fermilab. Proton interactions in the neutrino target at the main injector produce π^{0} and η mesons, which could decay into dark-matter (DM) particles mediated via a dark photon A^{'}. A convolutional neural network is trained to identify interactions of the DM particles in the liquid-argon time projection chamber (LArTPC) exploiting its imagelike reconstruction capability. In the absence of a DM signal, we provide limits at the 90% confidence level on the squared kinematic mixing parameter ϵ^{2} as a function of the dark-photon mass in the range 10≤M_{A^{'}}≤400 MeV. The limits cover previously unconstrained parameter space for the production of fermion or scalar DM particles χ for two benchmark models with mass ratios M_{χ}/M_{A^{'}}=0.6 and 2 and for dark fine-structure constants 0.1≤α_{D}≤1.

8.
Phys Rev Lett ; 132(15): 151801, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38683006

RESUMO

We present a measurement of η production from neutrino interactions on argon with the MicroBooNE detector. The modeling of resonant neutrino interactions on argon is a critical aspect of the neutrino oscillation physics program being carried out by the DUNE and Short Baseline Neutrino programs. η production in neutrino interactions provides a powerful new probe of resonant interactions, complementary to pion channels, and is particularly suited to the study of higher-order resonances beyond the Δ(1232). We measure a flux-integrated cross section for neutrino-induced η production on argon of 3.22±0.84(stat)±0.86(syst) 10^{-41} cm^{2}/nucleon. By demonstrating the successful reconstruction of the two photons resulting from η production, this analysis enables a novel calibration technique for electromagnetic showers in GeV accelerator neutrino experiments.

9.
Phys Rev Lett ; 132(4): 041801, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38335355

RESUMO

We present the first search for heavy neutral leptons (HNLs) decaying into νe^{+}e^{-} or νπ^{0} final states in a liquid-argon time projection chamber using data collected with the MicroBooNE detector. The data were recorded synchronously with the NuMI neutrino beam from Fermilab's main injector corresponding to a total exposure of 7.01×10^{20} protons on target. We set upper limits at the 90% confidence level on the mixing parameter |U_{µ4}|^{2} in the mass ranges 10≤m_{HNL}≤150 MeV for the νe^{+}e^{-} channel and 150≤m_{HNL}≤245 MeV for the νπ^{0} channel, assuming |U_{e4}|^{2}=|U_{τ4}|^{2}=0. These limits represent the most stringent constraints in the mass range 35

10.
J Endocrinol Invest ; 47(4): 833-841, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37815751

RESUMO

BACKGROUND: 21-Hydroxylase deficiency (21-OHD) is caused by pathogenic CYP21A2 variations. CYP21A2 is arranged in tandem with its highly homologous pseudogene CYP21A1P; therefore, it is prone to mismatch and rearrangement, producing different types of complex variations. There were few reports on using only one method to detect different CYP21A2 variants simultaneously. AIMS: Targeted long-read sequencing method was used to detect all types of CYP21A2 variants in a series of patients with 21-OHD. METHODS: A total of 59 patients with 21-OHD were enrolled from Peking Union Medical College Hospital. Long-range locus-specific PCR and long-read sequencing (LRS) were performed to detect the pathogenic variants in CYP21A2. RESULTS: Copy-number variants of CYP21A2 were found in 25.4% of patients, including 5.1% with 3 copies of CYP21A2, 16.9% with 1 copy of CYP21A2, and 3.4% with 0 copy of CYP21A2. The remaining 74.6% of patients had 2 copies of CYP21A2. Pathogenic variants were identified in all 121 alleles of 59 patients. Specifically, single-nucleotide variants and small insertions/deletions (< 50 bp) were detected in 79 alleles, of which conversed from CYP21A1P were detected in 63 alleles, and rare variants were found in the other 16 alleles. Large gene conversions (> 50 bp) from pseudogene were detected in 10 alleles, and different chimeric genes (CYP21A1P/CYP21A2 or TNXA/TNXB) formed by large deletions were detected in 32 alleles. Of all variants, p.I173N was the most common variant (19.0%). CONCLUSIONS: Our study demonstrated that targeted long-read sequencing is a comprehensive method for detecting CYP21A2 variations, which is helpful for genetic diagnosis in 21-OHD patients.


Assuntos
Hiperplasia Suprarrenal Congênita , Esteroide 21-Hidroxilase , Humanos , Esteroide 21-Hidroxilase/genética , Hiperplasia Suprarrenal Congênita/genética , Mutação , Pseudogenes , Tenascina/genética
11.
Public Health ; 226: 91-98, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38029699

RESUMO

OBJECTIVES: National-level data on the incidence of retinopathy of prematurity (ROP) in different regions of China is insufficient. This study aimed to compare ROP incidences and care practices in different regions of China and their relationship with regional gross domestic product (GDP) per capita. STUDY DESIGN: Retrospective cohort study. METHODS: All infants born at <32 weeks gestational age (GA) and admitted to 70 neonatal intensive care units (NICUs) from January 1, 2019, to December 31, 2020, were enrolled. Hospitals were categorised into three regional groups according to geographical locations and GDP per capita from high to low: Eastern, Central, and Western China. The incidence of death or ROP, and care practices were compared among the groups. RESULTS: A total of 18,579 infants were enrolled. Median GA was 29.9 (interquartile range 28.4-31.0) weeks and birth weight was 1318.1 (317.2) g. The percentage of GA <28 weeks, complete administration of antenatal steroids, and weight gain velocity during NICU stay were highest in Eastern China and lowest in Western China (all P < 0.01). In Eastern, Central, and Western China, the rates of death or any stage of ROP were 33.3%, 38.5%, and 39.2%, respectively (P < 0.01). CONCLUSIONS: There were considerable regional disparities in ROP incidence in preterm infants with GA <32 weeks in China. The incidence of death or ROP ranged from high to low in Western, Central, and Eastern China.


Assuntos
Recém-Nascido Prematuro , Retinopatia da Prematuridade , Gravidez , Lactente , Recém-Nascido , Humanos , Feminino , Idade Gestacional , Incidência , Retinopatia da Prematuridade/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Peso ao Nascer , China/epidemiologia
12.
Zhonghua Yi Xue Za Zhi ; 104(3): 218-221, 2024 Jan 16.
Artigo em Zh | MEDLINE | ID: mdl-38220448

RESUMO

The clinical characteristics, auxiliary examinations, skin and neuropathological features of 7 patients who had reticular cyanosis with peripheral neuropathy from the Department of Neurology, Huashan Hospital, Fudan University from January 2019 to December 2022 were retrospectively analyzed. Among the 7 patients, 5 were female and 2 were male.The age of onset of peripheral neuropathy was (39.8±21.3) years and the disease duration of peripheral neuropathy was (2.7±2.3) years. Three patients had acute onset and 4 patients had chronic onset. All the patients had limb numbness, with limb weakness in 6 patients and pain in 5 cases. Neuroelectrophysiological examination revealed 1 case of mononeuropathy, 2 cases of polyneuropathy, 2 cases of peripheral neuropathy, and 2 cases of sensory neuron neuropathy. Skin biopsy was performed in 3 patients, which presented hyperplasia and expansion of blood vessels in the dermis with lymphocyte infiltration. Nerve biopsy was performed in 3 patients, indicating axonal damage. Reticular cyanosis with peripheral neuropathy characterizes with numbness and weakness of limbs, most of which were accompanied by pain. Electrophysiological changes are in various forms. The pathological changes are dominated by the damage of axonal.


Assuntos
Livedo Reticular , Doenças do Sistema Nervoso Periférico , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Cianose/complicações , Hipestesia/complicações , Livedo Reticular/complicações , Dor , Estudos Retrospectivos
13.
Zhonghua Yi Xue Za Zhi ; 104(18): 1590-1600, 2024 May 14.
Artigo em Zh | MEDLINE | ID: mdl-38742346

RESUMO

Objective: To investigate the prognostic value of skeletal muscle measured by CT at the level of the fourth thoracic vertebra (T4) in advanced epidermal growth factor receptor (EGFR)-positive non-small cell lung cancer (NSCLC) patients treated with ecotinib. Methods: The study retrospectively reviewed clinical and pathological characteristics of 176 patients with advanced EGFR-positive NSCLC who received ecotinib and underwent chest CT scans at Wuhan Union Hospital between January 2017 and October 2020. Among them, 70 were male and 106 were female, with ages ranging from 27 to 80 (58.6±10.6) years. As of August 21, 2021, the median follow-up duration was 19.2 months (95%CI: 15.3 to 23.7 months). The optimal cut-off value of skeletal muscle density (T4-SMD) on CT images at the T4 level were determined using X-tile software. Kaplan-Meier analysis and log-rank test were used to plot progression-free survival curves. Cox proportional hazards regression models were employed to analyze factors influencing 1-year progression-free survival (PFS), and a nomogram prognostic model was constructed accordingly. Receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA) were utilized to evaluate the predictive value of the nomogram. Results: The T4-SMD [M (Q1,Q3)] of 176 patients was 42.56 (37.05, 45.93) HU. Patients were divided into low T4-SMD group (n=122) and high T4-SMD group (n=54) based on the cut-off value (The values for males and females were 49.44 and 41.41 HU, respectively) of T4-SMD. The median PFS time and 1-year PFS rate in the low T4-SMD group were significantly lower than those in the high T4-SMD group [10.4 (95%CI: 9.3-11.8) vs 13.7 (95%CI: 11.1-18.5) months, 36.1% vs 59.3%, respectively, P=0.034]. Eastern Cooperative Oncology Group performance status (HR=3.308, 95%CI: 1.183-9.247, P=0.023), lactate dehydrogenase level (HR=1.852, 95%CI: 1.037-3.307, P=0.037), systemic immune-inflammation index (HR=1.772, 95%CI: 1.019-3.080, P=0.043), and T4-SMD (HR=0.563, 95%CI: 0.325-0.974, P=0.040) were prognostic factors for 1-year PFS in advanced EGFR-positive NSCLC patients treated with ecotinib. A nomogram for predicting 1-year PFS of advanced EGFR-positive NSCLC patients treated with ecotinib was constructed based on the four indicators selected by multivariate Cox regression analysis. The area under the ROC curve of the nomogram was 0.775 (95%CI: 0.676-0.874). The calibration curve showed good consistency between the predicted and actual 1-year PFS. DCA demonstrated good clinical prediction effectiveness of the nomogram. Conclusion: Low T4-SMD is a prognostic risk factor for patients with advanced EGFR-positive NSCLC receiving icotinib therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Neoplasias Pulmonares , Músculo Esquelético , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Éteres de Coroa/uso terapêutico , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/tratamento farmacológico , Músculo Esquelético/diagnóstico por imagem , Prognóstico , Quinazolinas/uso terapêutico , Estudos Retrospectivos
14.
Zhonghua Fu Chan Ke Za Zhi ; 59(5): 391-400, 2024 May 25.
Artigo em Zh | MEDLINE | ID: mdl-38797569

RESUMO

Objective: To investigate the effect of rare ginsenosides (RGS) on reproductive injury induced by cyclophosphamide (CP) in female rats. Methods: Twenty-four female rats were divided into four groups [normal control (NC), RGS, CP, and CP+RGS group] with 6 rats in each group. CP group (the model group) and CP+RGS group (the treatment group) were intraperitoneally injected with CP 30 mg/kg for 5 days for modeling, and CP+RGS group was given RGS intragastric intervention. General growth status of rats in each group was observed, the organ index was calculated, and the pathological changes of ovary, uterus, liver and kidney were observed by hematoxylin-eosin staining. Serum levels of estradiol, follicle stimulating hormone (FSH), luteinizing hormone (LH), pro-inflammatory factors interleukin (IL) 6, IL-1ß, tumor necrosis factor-α were detected. The urine samples were collected after RGS treatment for metabonomics analysis. Metabolomic profiling based on ultra performance liquid chromatography (UPLC) coupled with mass spectrometry (MS) was used to analyze and determine the urine metabolites of rats in each group. Results: Compared with NC group, the ovary index of CP group [(0.054±0.015) %] was significantly decreased (P<0.05), the uterus index [(0.293±0.036) %] and estradiol level [(62.9±6.4) pmol/L] were significantly decreased (all P<0.01), serum levels of FSH, LH, IL-6 and IL-1ß [(20.4±1.0) U/L, (29.0±3.0) U/L, (185.4±28.6) ng/L, (72.9±2.0) ng/L, respectively] were significantly increased (all P<0.01). Compared with CP group, the ovary index in CP+RGS group [(0.075±0.010) %] was significantly increased (P<0.05), serum estradiol level [(122.1±16.2) pmol/L] was significantly increased (P<0.01), serum FSH, IL-1ß and IL-6 levels [(16.7±1.0) U/L, (111.8±17.4) ng/L, (60.1±2.2) ng/L, respectively] were significantly decreased (all P<0.01). Metabonomics analysis results showed that, a total of 352 metabolites were detected in urine, of which 12 were found to be potential markers associated with reproductive injury according to the screening standard. After treatment with RGS, differential metabolites were improved in the direction of NC group. Pathway enrichment suggests that the therapeutic effect of RGS was related to multiple metabolic pathways, including purine metabolism and taurine and hypotaurine metabolism. Conclusion: RGS might reduce inflammation and thus ameliorate the damage caused by CP to the reproductive system of female rats by affecting purine metabolism and other pathways.


Assuntos
Ciclofosfamida , Estradiol , Hormônio Foliculoestimulante , Ginsenosídeos , Metabolômica , Ovário , Ratos Sprague-Dawley , Útero , Animais , Feminino , Ratos , Ciclofosfamida/efeitos adversos , Ciclofosfamida/toxicidade , Ginsenosídeos/farmacologia , Hormônio Foliculoestimulante/sangue , Estradiol/sangue , Ovário/efeitos dos fármacos , Ovário/patologia , Ovário/metabolismo , Útero/efeitos dos fármacos , Útero/patologia , Útero/metabolismo , Hormônio Luteinizante/sangue , Cromatografia Líquida de Alta Pressão , Interleucina-6/metabolismo , Interleucina-6/sangue , Modelos Animais de Doenças , Interleucina-1beta/metabolismo , Interleucina-1beta/sangue , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/sangue , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fígado/patologia , Espectrometria de Massas , Rim/efeitos dos fármacos , Rim/patologia , Rim/metabolismo
15.
Zhonghua Fu Chan Ke Za Zhi ; 59(4): 299-306, 2024 Apr 25.
Artigo em Zh | MEDLINE | ID: mdl-38644276

RESUMO

Objective: To explore the value of optical coherence tomography (OCT) imaging system in evaluating cervical lesions in vivo. Methods: A total of 1 214 patients with cervical lesions were collected from January 2020 to December 2021 in the Third Affiliated Hospital of Zhengzhou University, Maternal and Chlid Heaith Hospital of Gushi County, Xinyang City, Henan Province, and Maternal and Chlid Heaith Hospital of Sui County, Shangqiu City, Henan Province. The age of the patients was (38.9±10.5) years (range: 16-77 years). All patients underwent in vivo cervical OCT examination and cervical biopsy pathology examination, and summarized the OCT image features of in vivo cervical lesions. Using the pathological diagnosis as the "gold standard", the accuracy, specificity, sensitivity, positive predictive value (PPV) and negative predictive value (NPV) of OCT image interpretation results were evaluated, as well as the consistency of OCT image diagnosis and pathological diagnosis. At the same time, the in vivo cervical OCT imaging system, as a newly developed screening tool, was compared with the traditional combined screening of human papillomavirus (HPV) and Thinprep cytologic test (TCT), to assess the screening effect. Results: By comparing the OCT images of the cervix in vivo with the corresponding HE images, the OCT image characteristics of the normal cervix and various types of cervical lesions in vivo were summarized. The accuracy, sensitivity, specificity, PPV and NPV of OCT image in the diagnosis of high-grade squamous intraepithelial lesion (HSIL) and above (HSIL+) were 93.4%, 88.5%, 95.0%, 85.0% and 96.2%, respectively. The accuracy, sensitivity, specificity, PPV and NPV of OCT for low-grade squamous intraepithelial lesion (LSIL) were 84.7%, 61.7%, 96.3%, 89.3% and 83.2%, respectively. The consistency between OCT image diagnosis and pathological diagnosis was strong (Kappa value was 0.701).The accuracy, sensitivity and specificity of OCT screening, HPV and TCT combined screening were 83.7% vs 64.9% (χ²=128.82, P<0.001), 77.8% vs 64.5% (χ²=39.01, P<0.001), 91.8% vs 65.4% (χ²=98.12, P<0.001), respectively. The differences were statistically significant. Conclusions: OCT imaging system has high sensitivity and specificity in the evaluation of cervical lesions in vivo, and has the characteristics of non-invasive, real-time and high efficiency. OCT examination is expected to become an effective method for the diagnosis of cervical lesions and cervical cancer screening.


Assuntos
Colo do Útero , Sensibilidade e Especificidade , Tomografia de Coerência Óptica , Neoplasias do Colo do Útero , Humanos , Feminino , Tomografia de Coerência Óptica/métodos , Adulto , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/diagnóstico , Pessoa de Meia-Idade , Colo do Útero/diagnóstico por imagem , Colo do Útero/patologia , Adolescente , Idoso , Displasia do Colo do Útero/diagnóstico por imagem , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/diagnóstico , Infecções por Papillomavirus/diagnóstico , Adulto Jovem , Esfregaço Vaginal , Biópsia , Valor Preditivo dos Testes , Detecção Precoce de Câncer/métodos
16.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(2): 261-267, 2024 Feb 06.
Artigo em Zh | MEDLINE | ID: mdl-38387960

RESUMO

This study explores the effects and possible mechanisms of nuclear factor E2 related factor 2 (NRF2) on ovarian granulosa cells, providing a scientific basis to prevent premature ovarian failure. An ovarian cell injury model was constructed by treating human ovarian granulosa cell (KGN cell) with 4-Vinylcyclohexene dioxide (VCD). Firstly, KGN cells were treated with different concentrations of VCD, and cell counting kit 8 (CCK-8) was used to detect ovarian cell proliferation. After determining IC50 by CCK8, the levels of estradiol and progesterone in the cell supernatant were detected using enzyme-linked immunosorbent assay (ELISA), reactive oxygen species (ROS) assay kit was used to detect the content of ROS in ovarian cells, real-time fluorescence quantitative polymerase chain reaction (qRT PCR) was used to detect the mRNA expression level of NRF2, and Western blot was used to detect the protein expression level of NRF2. Further, NRF2 silence (siNRF2) and overexpression (NRF2-OE) cell models were constructed through lentivirus transfection, and the effects of regulating NRF2 on VCD treated cell models were investigated by detecting hormone levels, oxidative stress indicators (ROS, SOD, GSH-Px), and autophagy (LC3B level). The results showed that VCD intervention inhibited the proliferation of ovarian granulosa cells in a time-dependent and dose-dependent manner (F>100, P<0.05), with an IC50 of 1.2 mmol/L at 24 hours. After VCD treatment, the level of estradiol in the cell supernatant decreased from (56.32±10.18) ng/ml to (24.59±8.75) ng/ml (t=5.78, P<0.05). Progesterone decreased from (50.25±7.03) ng/ml to (25.13±6.67) ng/ml (t=6.54, P<0.05). After VCD treatment, the SOD of cells decreased from (44.47±7.71) ng/ml to (30.92±4.97) ng/ml (t=3.61, P<0.05). GSH-Px decreased from (68.51±10.17) ng/ml to (35.19±6.59) ng/ml (t=5.73, P<0.05). Simultaneously accompanied by an increase in autophagy and a decrease in NRF2. This study successfully constructed KGN cell models that silenced NRF2 and overexpressed NRF2. Subsequently, this study treated each group of cells with VCD and found that the cell proliferation activity of the siNRF2 group was significantly reduced (t=8.37, P<0.05), while NRF2-OE could reverse the cell activity damage caused by VCD (t=3.37, P<0.05). The siNRF2 group had the lowest level of estradiol (t=5.78, P<0.05), while NRF2-OE could reverse the decrease in cellular estradiol levels caused by VCD (t=5.58, P<0.05). The siNRF2 group had the lowest progesterone levels (t=3.02, P<0.05), while NRF2-OE could reverse the decrease in cellular progesterone levels caused by VCD (t=2.41, P<0.05). The ROS level in the siNRF2 group was the highest (t=2.86, P<0.05), NRF2-OE could reverse the increase in ROS caused by VCD (t=3.14, P<0.05), the SOD enzyme content in the siNRF2 group was the lowest (t=2.98, P<0.05), and NRF2-OE could reverse the decrease in SOD enzyme content caused by VCD (t=4.72, P<0.05). The GSH-Px enzyme content in the siNRF2 group was the lowest (t=3.67, P<0.05), and NRF2-OE could reverse the decrease in antioxidant enzyme content caused by VCD (t=2.71, P<0.05). The LC3B level was highest in the siNRF2 group (t=2.45, P<0.05), and NRF2-OE was able to reverse the LC3B elevation caused by VCD (t=9.64, P<0.05). In conclusion, NRF2 inhibits ROS induced autophagy, thereby playing a role in reducing ovarian granulosa cell damage, which may be a potential target for premature ovarian failure.


Assuntos
Fator 2 Relacionado a NF-E2 , Insuficiência Ovariana Primária , Feminino , Humanos , Autofagia , Estradiol/metabolismo , Estradiol/farmacologia , Células da Granulosa/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/farmacologia , Estresse Oxidativo , Insuficiência Ovariana Primária/metabolismo , Progesterona/metabolismo , Progesterona/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Superóxido Dismutase/metabolismo , Superóxido Dismutase/farmacologia
17.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(1): 25-32, 2024 Jan 06.
Artigo em Zh | MEDLINE | ID: mdl-38228546

RESUMO

Objective: To evaluate the immunogenicity, safety, and immune persistence of the sequential booster with the recombinant protein-based COVID-19 vaccine (CHO cell) in healthy people aged 18-84 years. Methods: An open-label, multi-center trial was conducted in October 2021. The eligible healthy individuals, aged 18-84 years who had completed primary immunization with the inactivated COVID-19 vaccine 3 to 9 months before, were recruited from Shangyu district of Shaoxing and Kaihua county of Quzhou, Zhejiang province. All participants were divided into three groups based on the differences in prime-boost intervals: Group A (3-4 months), Group B (5-6 months) and Group C (7-9 months), with 320 persons per group. All participants received the recombinant COVID-19 vaccine (CHO cell). Blood samples were collected before the vaccination and after receiving the booster at 14 days, 30 days, and 180 days for analysis of GMTs, antibody positivity rates, and seroconversion rates. All adverse events were collected within one month and serious adverse events were collected within six months. The incidences of adverse reactions were analyzed after the booster. Results: The age of 960 participants was (52.3±11.5) years old, and 47.4% were males (455). The GMTs of Groups B and C were 65.26 (54.51-78.12) and 60.97 (50.61-73.45) at 14 days after the booster, both higher than Group A's 44.79 (36.94-54.30) (P value<0.05). The GMTs of Groups B and C were 23.95 (20.18-28.42) and 27.98 (23.45-33.39) at 30 days after the booster, both higher than Group A's 15.71 (13.24-18.63) (P value <0.05). At 14 days after the booster, the antibody positivity rates in Groups A, B, and C were 91.69% (276/301), 94.38% (302/320), and 93.95% (295/314), respectively. The seroconversion rates in the three groups were 90.37% (272/301), 93.75% (300/320), and 93.31% (293/314), respectively. There was no significant difference among these rates in the three groups (all P values >0.05). At 30 days after the booster, antibody positivity rates in Groups A, B, and C were 79.60% (238/299), 87.74% (279/318), and 90.48% (285/315), respectively. The seroconversion rates in the three groups were 76.92% (230/299), 85.85% (273/318), and 88.25% (278/315), respectively. There was a significant difference among these rates in the three groups (all P values <0.001). During the sequential booster immunization, the incidence of adverse events in 960 participants was 15.31% (147/960), with rates of about 14.38% (46/320), 17.50% (56/320), and 14.06% (45/320) in Groups A, B, and C, respectively. The incidence of adverse reactions was 8.02% (77/960), with rates of about 7.50% (24/320), 6.88% (22/320), and 9.69% (31/320) in Groups A, B, and C, respectively. No serious adverse events related to the booster were reported. Conclusion: Healthy individuals aged 18-84 years, who had completed primary immunization with the inactivated COVID-19 vaccine 3 to 9 months before, have good immunogenicity and safety profiles following the sequential booster with the recombinant COVID-19 vaccine (CHO cell).


Assuntos
Vacinas contra COVID-19 , COVID-19 , Masculino , Cricetinae , Animais , Humanos , Adulto , Pessoa de Meia-Idade , Feminino , Imunização Secundária , Células CHO , COVID-19/prevenção & controle , Proteínas Recombinantes , Anticorpos Antivirais , Anticorpos Neutralizantes
18.
Zhonghua Wai Ke Za Zhi ; 62(6): 543-548, 2024 Jun 01.
Artigo em Zh | MEDLINE | ID: mdl-38682625

RESUMO

Objective: To report the clinical efficacy of adjuvant therapy based on pathological results following immunotherapy combined with targeted therapy and sequential curative surgical procedures in patients with initially unresectable hepatocellular carcinoma. Methods: This is a retrospective case series study. Data from 100 patients who underwent adjuvant therapy based on pathological results following immunotherapy combined with targeted therapy and sequential curative surgical procedures with long-term survival were collected from December 2018 to December 2022 at the Faculty of Hepato-Pancreato-Biliary Surgery, First Medical Center, Chinese People's Liberation Army General Hospital. According to inclusion and exclusion criteria, 47 cases were included, among which patients who met the discontinuation criteria and maintained a drug-free tumor-free status. Thirty-nine male and eight female patients were included, with an age of (54.2±18.8)years(range:38 to 73 years) at initial diagnosis. At the time of initial diagnosis, 43 cases (91.5%) were classified as Barcelona Clinic Liver Cancer stage C. Survival curves were made using Kaplan Meier method. Results: Forty-seven patients underwent R0 resection, all achieved a drug-free tumor-free state through postoperative adjuvant therapy based on pathological examination results. Thirty-six patients(76.6%) maintained a drug-free tumor-free survival status for more than 6 months,28 patients(59.6%) for more than 12 months,and 8 patients(17.0%) for more than 24 months. The longest drug-free tumor-free survival in this cohort reached 48 months. The median follow-up time in this study was 32 months. After diagnosis, the overall survival rates at 1- and 3- years were 97.7%(95%CI:93.4% to 100%) and 90.7%(95%CI:82.5% to 99.8%). The postoperative recurrence-free survival rates at 1- and 3- years were 91.0%(95%CI:83.0% to 99.8%) and 71.3%(95%CI:58.7% to 86.5%). Conclusions: The adjuvant therapy based on pathological results following immunotherapy combined with targeted therapy and sequential curative surgical approach provides long-term survival benefits for patients with initially unresectable hepatocellular carcinoma. Standardized adjuvant therapy maybe sustain long-term tumor-free status,and achieve drug-free tumor-free survival.


Assuntos
Carcinoma Hepatocelular , Imunoterapia , Neoplasias Hepáticas , Humanos , Masculino , Feminino , Estudos Retrospectivos , Carcinoma Hepatocelular/terapia , Carcinoma Hepatocelular/cirurgia , Pessoa de Meia-Idade , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/cirurgia , Adulto , Idoso , Terapia Combinada , Quimioterapia Adjuvante , Taxa de Sobrevida , Hepatectomia
19.
Zhonghua Xin Xue Guan Bing Za Zhi ; 52(2): 165-171, 2024 Feb 24.
Artigo em Zh | MEDLINE | ID: mdl-38326068

RESUMO

Objective: To explore the application value of quantitative flow ratio (QFR) in the hemodynamic evaluation of myocardial bridge and to preliminarily evaluate the correlation and related influencing factors between deformation quantitative flow ratio (D-QFR) and QFR. Methods: This is a cross-sectional study. Patients with CAG-confirmed simple myocardial bridge of the middle anterior descending coronary artery from June 2012 to June 2022 at the Air Force Medical Center were retrospectively included in this study. Systolic stenosis of mural coronary arteries (MCA) and myocardial bridge length were measured using quantitative coronary angiography. The patients were divided into mild stenosis group (<50% systolic stenosis) and moderate-to-severe stenosis group (≥50% systolic stenosis) according to the Nobel grading criteria. At different time periods (systolic and diastolic), the QFR values were measured at 3 locations (1 to 2 cm before the MCA entrance, the middle segment of the MCA, and 1 to 2 cm after the MCA exit), denoted as QFRa, QFRb, and QFRc, respectively, and the D-QFR values, incorporating vessel deformation information, were recorded. The MCA distal QFR≤0.8 in either stage was defined as an abnormal QFR value. QFR values were compared between the two groups at different locations and within each group. Factors associated with abnormal QFR values were analysed using multifactorial logistic regression. Spearman rank correlation analysis was used to examine the correlation between D-QFR values and systolic and diastolic QFR values.Multiple linear regression was used to analyse the factors associated with D-QFR. Results: A total of 83 patients were enrolled, including 58 males, aged (57.1±13.1) years. There were 48 cases in the mild stenosis group and 35 cases in the moderate-to-severe stenosis group, and the differences in systolic and diastolic QFRb and QFRc values between the two groups were statistically significant (all P<0.05). Within-group comparisons showed the values of QFRb and QFRc in the systolic phase were lower than those in the diastolic phase; QFRb and QFRc were both lower than QFRa during the same period (all P<0.05). Multifactorial logistic regression analysis showed that MCA systolic stenosis (OR=1.225, 95%CI 1.093-1.372, P<0.001) was an influential factor for abnormal QFR. D-QFR values were positively correlated with both systolic and diastolic QFR values (correlation coefficients were 0.849 and 0.675, respectively, both P<0.01). Multiple linear regression analysis showed that D-QFR values were negatively correlated with age (ß=-0.208, P=0.029), systolic stenosis (ß=-0.500, P<0.001), and myocardial bridge length (ß=-0.211, P=0.036). Conclusions: The QFR values in middle and distal of myocardial bridge decrease. The systolic stenosis rate of myocardial bridge is an important factor affecting QFR value. D-QFR is positively correlated with both systolic and diastolic QFR values. Age, myocardial bridge systolic stenosis rate and length are factors influencing the D-QFR values.


Assuntos
Doença da Artéria Coronariana , Estenose Coronária , Reserva Fracionada de Fluxo Miocárdico , Masculino , Humanos , Estudos Retrospectivos , Constrição Patológica , Estudos Transversais , Miocárdio , Vasos Coronários , Angiografia Coronária , Índice de Gravidade de Doença , Hemodinâmica , Valor Preditivo dos Testes
20.
Angew Chem Int Ed Engl ; 63(18): e202402007, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38407551

RESUMO

Pathological hyperphosphorylation and aggregation of microtubule-associated Tau protein contribute to Alzheimer's Disease (AD) and other related tauopathies. Currently, no cure exists for Alzheimer's Disease. Aptamers offer significant potential as next-generation therapeutics in biotechnology and the treatment of neurological disorders. Traditional aptamer selection methods for Tau protein focus on binding affinity rather than interference with pathological Tau. In this study, we developed a new selection strategy to enrich DNA aptamers that bind to surviving monomeric Tau protein under conditions that would typically promote Tau aggregation. Employing this approach, we identified a set of aptamer candidates. Notably, BW1c demonstrates a high binding affinity (Kd=6.6 nM) to Tau protein and effectively inhibits arachidonic acid (AA)-induced Tau protein oligomerization and aggregation. Additionally, it inhibits GSK3ß-mediated Tau hyperphosphorylation in cell-free systems and okadaic acid-mediated Tau hyperphosphorylation in cellular milieu. Lastly, retro-orbital injection of BW1c tau aptamer shows the ability to cross the blood brain barrier and gain access to neuronal cell body. Through further refinement and development, these Tau aptamers may pave the way for a first-in-class neurotherapeutic to mitigate tauopathy-associated neurodegenerative disorders.


Assuntos
Doença de Alzheimer , Tauopatias , Proteínas tau , Humanos , Doença de Alzheimer/metabolismo , Neurônios/metabolismo , Ácido Okadáico/metabolismo , Ácido Okadáico/farmacologia , Ácido Okadáico/uso terapêutico , Fosforilação , Proteínas tau/antagonistas & inibidores , Proteínas tau/metabolismo , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo , Tauopatias/patologia , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/farmacologia
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