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1.
Nature ; 594(7861): 33-36, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34002091

RESUMO

The extension of the cosmic-ray spectrum beyond 1 petaelectronvolt (PeV; 1015 electronvolts) indicates the existence of the so-called PeVatrons-cosmic-ray factories that accelerate particles to PeV energies. We need to locate and identify such objects to find the origin of Galactic cosmic rays1. The principal signature of both electron and proton PeVatrons is ultrahigh-energy (exceeding 100 TeV) γ radiation. Evidence of the presence of a proton PeVatron has been found in the Galactic Centre, according to the detection of a hard-spectrum radiation extending to 0.04 PeV (ref. 2). Although γ-rays with energies slightly higher than 0.1 PeV have been reported from a few objects in the Galactic plane3-6, unbiased identification and in-depth exploration of PeVatrons requires detection of γ-rays with energies well above 0.1 PeV. Here we report the detection of more than 530 photons at energies above 100 teraelectronvolts and up to 1.4 PeV from 12 ultrahigh-energy γ-ray sources with a statistical significance greater than seven standard deviations. Despite having several potential counterparts in their proximity, including pulsar wind nebulae, supernova remnants and star-forming regions, the PeVatrons responsible for the ultrahigh-energy γ-rays have not yet been firmly localized and identified (except for the Crab Nebula), leaving open the origin of these extreme accelerators.

2.
Phys Rev Lett ; 133(7): 071501, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39213544

RESUMO

On 9 October 2022, the Large High Altitude Air Shower Observatory (LHAASO) reported the observation of the very early TeV afterglow of the brightest-of-all-time gamma-ray burst 221009A, recording the highest photon statistics in the TeV band ever obtained from a gamma-ray burst. We use this unique observation to place stringent constraints on the energy dependence of the speed of light in vacuum, a manifestation of Lorentz invariance violation (LIV) predicted by some quantum gravity (QG) theories. Our results show that the 95% confidence level lower limits on the QG energy scales are E_{QG,1}>10 times the Planck energy E_{Pl} for the linear LIV effect, and E_{QG,2}>6×10^{-8}E_{Pl} for the quadratic LIV effect. Our limits on the quadratic LIV case improve previous best bounds by factors of 5-7.

3.
Phys Rev Lett ; 133(6): 061001, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39178452

RESUMO

In this Letter we try to search for signals generated by ultraheavy dark matter at the Large High Altitude Air Shower Observatory (LHAASO) data. We look for possible γ rays by dark matter annihilation or decay from 16 dwarf spheroidal galaxies in the field of view of the LHAASO. Dwarf spheroidal galaxies are among the most promising targets for indirect detection of dark matter that have low fluxes of astrophysical γ-ray background while having large amount of dark matter. By analyzing more than 700 days of observational data at LHAASO, no significant dark matter signal from 1 TeV to 1 EeV is detected. Accordingly we derive the most stringent constraints on the ultraheavy dark matter annihilation cross section up to EeV. The constraints on the lifetime of dark matter in decay mode are also derived.

4.
Phys Rev Lett ; 132(13): 131002, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38613275

RESUMO

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15 PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

5.
Phys Rev Lett ; 131(15): 151001, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37897763

RESUMO

The diffuse Galactic γ-ray emission, mainly produced via interactions between cosmic rays and the interstellar medium and/or radiation field, is a very important probe of the distribution, propagation, and interaction of cosmic rays in the Milky Way. In this Letter, we report the measurements of diffuse γ rays from the Galactic plane between 10 TeV and 1 PeV energies, with the square kilometer array of the Large High Altitude Air Shower Observatory (LHAASO). Diffuse emissions from the inner (15°10 TeV). The energy spectrum in the inner Galaxy regions can be described by a power-law function with an index of -2.99±0.04, which is different from the curved spectrum as expected from hadronic interactions between locally measured cosmic rays and the line-of-sight integrated gas content. Furthermore, the measured flux is higher by a factor of ∼3 than the prediction. A similar spectrum with an index of -2.99±0.07 is found in the outer Galaxy region, and the absolute flux for 10≲E≲60 TeV is again higher than the prediction for hadronic cosmic ray interactions. The latitude distributions of the diffuse emission are consistent with the gas distribution, while the longitude distributions show clear deviation from the gas distribution. The LHAASO measurements imply that either additional emission sources exist or cosmic ray intensities have spatial variations.

6.
Beijing Da Xue Xue Bao Yi Xue Ban ; 55(3): 495-501, 2023 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-37291926

RESUMO

OBJECTIVE: To explore the association between periconceptional supplementation of folic acid or multiple-micronutrients containing folic acid(MMFA) and risk of preterm delivery in women with natural conception, singleton pregnancy and vaginal delivery. METHODS: A retrospective cohort study was performed based on the prenatal health care system and hospital information system of Tongzhou Maternal and Child Health Hospital of Beijing and the women who had their prenatal care in the hospital from January 2015 to December 2018 were included. The information of 16 332 women who conceived naturally, had a singleton pregnancy, and delivered vaginally was collected. Compliance scores were constructed based on the time of initiation and the frequency of taking nutritional supplements. The association between maternal periconceptional micronutrient supplementation, including pure folic acid (FA) pills or MMFA and the rate of preterm delivery was evaluated using Logistic regression models. RESULTS: The preterm delivery rate (gestational week < 37 weeks) of the study population was 3.8%, and the mean (standard deviation) of gestational age was (38.98±1.37) weeks. A total of 6 174 (37.8%) women took FA during the periconceptional period, 8 646 (52.9%) women took MMFA, and 1 512 (9.3%) women did not take any nutritional supplements. The association between periconceptional supplementation of FA or MMFA and risk of preterm delivery in women was not statistically significant [adjusted odds ratio (aOR)=1.01, 95%CI: 0.74-1.37]. The associations with preterm birth were not statistically significant in further analysis by the type of nutritional supplements, time of initiation, and the frequency of supplementation. In addition, the association between the compliance score of taking supplements and the rate of preterm delivery was not statistically significant, either. CONCLUSION: This study did not find an association between the risk of preterm delivery and the use of FA or MMFA during the periconcep-tional period in women with natural conception, singleton pregnancy, and vaginal delivery. In the future, multicenter studies with large-scale prospective cohort or population-based randomized controlled trials are warranted to confirm the association between taking FA or MMFA during the periconceptional period and preterm delivery among women.


Assuntos
Ácido Fólico , Nascimento Prematuro , Gravidez , Feminino , Criança , Recém-Nascido , Humanos , Lactente , Masculino , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/prevenção & controle , Estudos Prospectivos , Estudos Retrospectivos , Suplementos Nutricionais , Micronutrientes
7.
Phys Rev Lett ; 128(5): 051102, 2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35179919

RESUMO

Recently, the LHAASO Collaboration published the detection of 12 ultrahigh-energy γ-ray sources above 100 TeV, with the highest energy photon reaching 1.4 PeV. The first detection of PeV γ rays from astrophysical sources may provide a very sensitive probe of the effect of the Lorentz invariance violation (LIV), which results in decay of high-energy γ rays in the superluminal scenario and hence a sharp cutoff of the energy spectrum. Two highest energy sources are studied in this work. No signature of the existence of the LIV is found in their energy spectra, and the lower limits on the LIV energy scale are derived. Our results show that the first-order LIV energy scale should be higher than about 10^{5} times the Planck scale M_{Pl} and that the second-order LIV scale is >10^{-3}M_{Pl}. Both limits improve by at least one order of magnitude the previous results.

8.
Phys Rev Lett ; 129(26): 261103, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36608208

RESUMO

The kilometer square array (KM2A) of the large high altitude air shower observatory (LHAASO) aims at surveying the northern γ-ray sky at energies above 10 TeV with unprecedented sensitivity. γ-ray observations have long been one of the most powerful tools for dark matter searches, as, e.g., high-energy γ rays could be produced by the decays of heavy dark matter particles. In this Letter, we present the first dark matter analysis with LHAASO-KM2A, using the first 340 days of data from 1/2-KM2A and 230 days of data from 3/4-KM2A. Several regions of interest are used to search for a signal and account for the residual cosmic-ray background after γ/hadron separation. We find no excess of dark matter signals, and thus place some of the strongest γ-ray constraints on the lifetime of heavy dark matter particles with mass between 10^{5} and 10^{9} GeV. Our results with LHAASO are robust, and have important implications for dark matter interpretations of the diffuse astrophysical high-energy neutrino emission.

9.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(5): 971-980, 2022 Oct 18.
Artigo em Chinês | MEDLINE | ID: mdl-36241241

RESUMO

OBJECTIVE: To evaluate pharmacokinetics (PK), efficacy, and safety of atezolizumab (anti-PD-L1) in high interest cancers in China, including esophageal cancer (EC), gastric cancer (GC), hepatocellular carcinoma (HCC), nasopharyngeal cancer (NPC), and non-small cell lung can-cer (NSCLC). METHODS: This phase I, open-label study was conducted at 6 Chinese sites from August 4, 2016 to April 15, 2019. The patients were ≥18 years old with a histologically documented incurable or metastatic solid tumor that was advanced or recurrent and had progressed since the last anti-tumor the-rapy. The PK phase characterized PK and safety of atezolizumab following multiple-dose administration when atezolizumab was administered as a single agent. The extension phase studied safety and efficacy of atezolizumab, as monotherapy (EC, GC, HCC, NPC) and with chemotherapy (NSCLC). RESULTS: This study enrolled 120 patients (PK phase: n=20; extension phase: n=20/cohort). Fourty-two patients (42.0%) were PD-L1 positive in atezolizumab monotherapy group (100 patients), of the 9 patients (9.0%) with microsatellite instability-high (MSI-H) tumors. Atezolizumab clearance was 0.219 L/d, and steady state was reached after 6 to 9 weeks (2-3 cycles) of repeated dosing. Objective response rates (ORRs) in EC, GC, HCC, NPC, and NSCLC were 10.0%, 15.0%, 10.0%, 5.0%, and 40.0%, respectively. In the patients with PD-L1 positive tumors, ORR was 11.9% with atezolizumab and 46.2% with atezolizumab plus gemcitabine and cisplatin. Two GC patients achieved durable response after pseudo-progression. The most common treatment-related adverse events in the atezolizumab monotherapy group were fatigue, anemia, fever, and decreased white blood cell count. The most common treatment-related adverse events in the combination group were anemia, decreased white blood cell count, and decreased appetite. No new safety signals were identified. CONCLUSION: Atezolizumab's PK, efficacy, and safety were similar in Chinese patients vs. global patients in previous studies.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Neoplasias Pulmonares , Neoplasias Nasofaríngeas , Adolescente , Anticorpos Monoclonais Humanizados , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Cisplatino/uso terapêutico , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Neoplasias Nasofaríngeas/induzido quimicamente , Neoplasias Nasofaríngeas/tratamento farmacológico
10.
Phys Rev Lett ; 126(24): 241103, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213924

RESUMO

We report the discovery of an extended very-high-energy (VHE) gamma-ray source around the location of the middle-aged (207.8 kyr) pulsar PSR J0622+3749 with the Large High-Altitude Air Shower Observatory (LHAASO). The source is detected with a significance of 8.2σ for E>25 TeV assuming a Gaussian template. The best-fit location is (right ascension, declination) =(95.47°±0.11°,37.92°±0.09°), and the extension is 0.40°±0.07°. The energy spectrum can be described by a power-law spectrum with an index of -2.92±0.17_{stat}±0.02_{sys}. No clear extended multiwavelength counterpart of the LHAASO source has been found from the radio to sub-TeV bands. The LHAASO observations are consistent with the scenario that VHE electrons escaped from the pulsar, diffused in the interstellar medium, and scattered the interstellar radiation field. If interpreted as the pulsar halo scenario, the diffusion coefficient, inferred for electrons with median energies of ∼160 TeV, is consistent with those obtained from the extended halos around Geminga and Monogem and much smaller than that derived from cosmic ray secondaries. The LHAASO discovery of this source thus likely enriches the class of so-called pulsar halos and confirms that high-energy particles generally diffuse very slowly in the disturbed medium around pulsars.

11.
Zhonghua Zhong Liu Za Zhi ; 43(11): 1177-1182, 2021 Nov 23.
Artigo em Chinês | MEDLINE | ID: mdl-34794220

RESUMO

Objective: To investigate the correlation between UGT1A1 polymorphisms and the irinotecan plus S-1 regimen-induced toxicities in Chinese advanced esophageal squamous cell carcinoma (ESCC) patients. Methods: A total of 46 recurrent or metastatic ESCC patients selected from ESWN 01 trial were randomly assigned to irinotecan plus S-1 group [intravenous infusion of irinotecan (160 mg/m(2)) on day 1 and oral S-1 (80-120 mg) on days 1-10, repeated every 14 days]. Peripheral venous blood at baseline was collected and genomic DNA was extracted. The genetic polymorphisms of UGT1A1*6 and UGT1A1*28 were analyzed by polymerase chain reaction (PCR) amplification. Irinotecan plus S-1 regimen-induced toxicities of patients with different UGT1A1 polymorphisms were observed. The correlation between UGT1A1 polymorphisms and the adverse effects was analyzed. Results: Among the 46 patients, the numbers of UGT1A1*6 wild type genotype (GG), mutant heterozygote (GA) and mutant homozygote (AA) were 30, 15 and 1, while those with UGT1A1*28 wild type genotype (TA6/6), mutant heterozygote (TA6/7) and mutant homozygote (TA7/7) were 36, 8 and 2, respectively. Only one patient with UGT1A1*6 AA genotype occurred grade 3 diarrhea, while one of the 2 patients with UGT1A1*28 TA7/7 genotype occurred grade 4 diarrhea. No neutropenia was observed in the patient with UGT1A1*6 AA genotype, however, both of the two patients with UGT1A1*28 TA7/7 genotype occurred grade 3-4 neutropenia. Patients with UGT1A1*28 genetic polymorphism (TA 6/7 or TA7/7) had a higher response rate compared with wild-type TA6/6 carriers. (55.6% versus 26.5%). Conclusions: The homozygous genotype of UGT1A1*6 AA and UGT1A1*28 TA7/7 are rare (<5%) in Chinese ESCC population. Not all homozygous AA and TA7/7 carriers occur severe dose limited toxicities (DLT) when treated with irinotecan (160 mg/m(2)) plus S-1 regimen for 2 weeks. However, it's still necessary torigorously observe the occurrence of severe diarrhea and neutropenia in patients with UGT1A1*6 AA and UGT1A1*28 TA7/7 and adjust the dose timely.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Camptotecina/efeitos adversos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Genótipo , Glucuronosiltransferase/genética , Humanos , Irinotecano/efeitos adversos , Polimorfismo Genético , Estudos Prospectivos
12.
Neoplasma ; 66(1): 83-91, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30509084

RESUMO

Angiotensin II (Ang II) has been strongly associated with biological behavior in human malignant tumors; nevertheless, its function in hepatic carcinoma growth and progression is still not well understood. This study investigates the effect and mechanism of Ang II on the HepG2 and Hep3B hepatic carcinoma cell lines in vitro. The effect of Ang II on HepG2 and Hep3B cell viability was examined by cell counting kit-8 assay (CCK-8). Quantitative real-time PCR and Western blot analysis detected the expression of angiotensin type 1 and type 2 receptors (AT1 and AT2), total extra-cellular signal-regulated kinases 1/2 (ERK1/2), phospho-ERK1/2 (p-ERK1/2) and Bcl-2 and c-Myc. Ang II significantly promoted HepG2 cell proliferation by affecting AT1 and AT2 expression and induced ERK1/2 pathway activation. This was reversed by treating HepG2 and Hep3B cells with AT1 blockers; candesartan, Raf inhibitor sorafenib, and ERK1/2 inhibitor PD98059. Ang II also up-regulated the expression of Bcl-2 and c-Myc in HepG2 cells, and our results suggest that Ang II has a positive role in HepG2 and Hep3B cell proliferation through the AT1/Raf/ERK1/2 signaling pathway.


Assuntos
Angiotensina II/metabolismo , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Sistema de Sinalização das MAP Quinases , Proliferação de Células , Células Hep G2 , Humanos , Receptor Tipo 1 de Angiotensina , Receptor Tipo 2 de Angiotensina
13.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(6): 1071-1077, 2019 Dec 18.
Artigo em Chinês | MEDLINE | ID: mdl-31848507

RESUMO

OBJECTIVE: To evaluate the diagnostic value of 18F-FDG PET/CT and tumor markers (CEA,CA19-9,CA24-2) in detection for recurrence and metastasis of postoperative colorectal moderately differentiated adenocarcinoma. METHODS: Fifty-five patients were enrolled in this study. All of the patients were tested with serum CEA within 2 weeks when they underwent 18F-FDG PET/CT scan, and some patients were tested with serum CA19-9 and CA24-2 simultaneously. According to the pathology and clinical results of their follow-up, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 18F-FDG PET/CT and tumor markers were calculated based on different divided groups, respectively. RESULTS: According to the pathology and the results of their clinical follow-up, the sensitivity of 18F-FDG PET/CT, CEA, CA19-9, CA24-2 and the combination of those three tumor markers were 95.74%, 68.09%, 28.57%, 40.00% and 74.47%, respectively. The specificity of 18F-FDG PET/CT, CEA, CA19-9, CA24-2 and the combination of those three tumor markers were 75.00%, 50.00%, 66.67%, 71.43% and 50.00%, respectively. The positive predictive valueof 18F-FDG PET/CT, CEA, CA19-9, CA24-2 and the combination of those three tumor markers were 95.74%, 88.89%, 85.71%, 88.89% and 89.74%, respectively. The negative predictive value of 18F-FDG PET/CT, CEA, CA19-9, CA24-2 and the combination of those three tumor markers were 75.00%, 26.67%, 11.42%, 17.24%, 25.00%, respectively. The accuracy of 18F-FDG PET/CT, CEA, CA19-9, CA24-2 and the combination of those three tumor markers were 92.73%, 65.47%, 32.65%, 44.68% and 70.91%, respectively. There were 2 cases of false positive and 2 cases of false negative in 18F-FDG PET/CT. CONCLUSION: 18F-FDG PET/CT has high value in detecting recurrence and metastasis of postoperative colorectal carcinoma. Tumor markers have the positive value to imply the recurrence and metastasis of postoperative colorectal carcinoma and are useful to indicate when to perform the 18F-FDG PET/CT. The combination of tumor markers could improve the diagnostic efficiency to some extent.


Assuntos
Adenocarcinoma , Neoplasias Colorretais , Adenocarcinoma/diagnóstico , Biomarcadores Tumorais , Antígeno CA-19-9 , Antígeno Carcinoembrionário , Neoplasias Colorretais/diagnóstico , Fluordesoxiglucose F18 , Humanos , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tomografia por Emissão de Pósitrons , Recidiva
14.
Zhonghua Bing Li Xue Za Zhi ; 48(9): 710-714, 2019 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-31495092

RESUMO

Objective: To investigate the clinicopathological features, diagnosis, differential diagnosis, treatment and prognosis of pediatric alveolar rhabdomyosarcoma (ARMS). Methods: The clinical and pathological data of 25 pediatric ARMS from 2008 to 2018 in Children's Hospital of Fudan University were collected. This histomorphology was assessed, and FOXO1 gene rearrangement was detected with FISH. The treatment details and outcome were analyzed. Results: There were 13 males and 12 females, with ages range from 19 days to 14 years (median 6 years, mean 6.2 years). The ARMS were located in the limbs (13 cases), head and neck (4 cases), trunk (3 cases), abdominal cavity (3 cases), scrotum (1 case) and perianal region (1 case). The ARMS were classified histologically as classic group (18 cases), solid group (5 cases) and embryonic-alveolar mixed group (2 cases). The typical pathological characteristics were small dark round cells arranged in solid, glandular and papillary patterns. The tumor cells expressed ALK (D5F3) (21/25, 84.0%), muscle origin DES (23/25, 92.0%), myogenin (22/25, 88.0%), MYOD1 (19/25, 76.0%), and in some cases they also expressed neurogenic marker Syn (6/25, 24.0%). FOXO1 gene rearrangement was detected by FISH in 24/25 cases (96.0%). Conclusion: Pediatric ARMS is rare and has unique clinicopathological characteristics, and needs to be differentiated from other common small round cell malignancies in children. ALK, DES, myogenin, MYOD1 immunohistochemistry and FOXO1 gene rearrangement are valuable aid in the diagnosis of ARMS.


Assuntos
Rabdomiossarcoma Alveolar , Rabdomiossarcoma Embrionário , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Recém-Nascido , Masculino , Miogenina , Prognóstico
16.
Zhonghua Gan Zang Bing Za Zhi ; 26(8): 601-606, 2018 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-30317792

RESUMO

Objective: To study the effect and mechanism of angiotensin (Ang II) on the proliferation of human hepatocellular carcinoma HepG2 cells. Methods: The effects of different concentrations of Ang II's (10(-8)-10(-4) mol/L) on proliferated hepatocellular carcinoma HepG2 cells were detected by CCK-8 assay. The expression of angiotensin II type 1 receptor (AT1) protein and activation of ERK1/2 protein in hepatocellular carcinoma HepG2 cells after processing with Ang II were assayed by Western blot. The cells were pretreated with candesartan (AT1 receptor antagonist), sorafenib (Raf kinase inhibitor) and PD98059 (ERK1/2 inhibitor) for 1.5 h and then Ang II (10(-6) mol/L) was added. CCK-8 assay was used to determine whether it could reverse the proliferation of Ang II, and ERK phosphorylation levels were detected by Western blot. The changes in Bcl-2 and c-myc gene expression before and after Ang II processing were detected by Rt-PCR. According to different data, t-test, one-way analysis of variance or SNK method were used for statistical analysis. Results: HepG2 cells treated with different concentrations of Ang II promoted cell proliferation after 24h and 48h. After 24 h, cell vitality was strongest with Ang II concentration 10(-5) mol/L and the absorbance value was 0.990 8±0.097 8; and again after 48 h, the cell viability was strongest with Ang II concentration 10(-6) mol/L and the absorbance value was 1.302 7 ± 0.030 9. Moreover, the pro-proliferation effect of Ang II on HepG2 cells blocked candesartan, sorafenib and ERK1/2 isolated inhibitors. After treatment with 10(-6) mol/L Ang II, Western blot showed that Ang II significantly promoted AT1 receptor expression and phosphorylation of ERK1/2 protein confirmed that Ang II activated the AT1/RAF/ERK1/2 signaling pathway. In addition, Rt-PCR detection showed that the downstream of Bcl-2 and c-myc genes expressions rose significantly when the concentration of Ang II ranged from 10(-8) to 10(-6) mol/L. Conclusion: Ang II can promote the proliferation of HepG2 cells by activating AT1/Raf /ERK1/2 signaling pathway and enhance the downstream of Bcl-2 and c-myc gene expression.


Assuntos
Angiotensina II/farmacologia , Proliferação de Células/efeitos dos fármacos , Genes bcl-2/efeitos dos fármacos , Genes myc/efeitos dos fármacos , Células Hep G2/efeitos dos fármacos , Carcinoma Hepatocelular , Linhagem Celular , Células Cultivadas , Genes bcl-2/genética , Genes myc/genética , Humanos , Neoplasias Hepáticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
Genet Mol Res ; 14(4): 17972-81, 2015 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-26782444

RESUMO

The aim of this study was to investigate the effect of local administration of odanacatib (ODN) on orthodontic root resorption and the status of alveolar bone metabolism in rat molars. All specimens were scanned using microcomputed tomography and then the raw images were reconstructed. The total volume of the root resorption craters of the 60 g-NS (normal saline) group was higher than in the 60 g-ODN group and the control group. In the 60 g-NS group, the bone volume fraction values of alveolar bone were significantly decreased compared with the other 2 groups. There were no significant differences in the bone volume fraction values of the tibiae among the 3 groups. The results of tartrate-resistant acid phosphatase-positive (TRAP+) numbers showed that there was no difference between the 60 g-NS group and the 60 g-ODN group. The expression of cathepsin K was decreased significantly in the 60 g-ODN group. These results indicate that ODN reduces orthodontics-induced external root resorption and increases alveolar bone metabolism. This may be because ODN inhibits the activity of odontoclasts, but maintains the quantity of odontoclasts and enhances bone formation. ODN promotes local alveolar bone metabolism, but does not affect systemic bone metabolism.


Assuntos
Perda do Osso Alveolar/tratamento farmacológico , Compostos de Bifenilo/administração & dosagem , Osso e Ossos/metabolismo , Reabsorção da Raiz/tratamento farmacológico , Perda do Osso Alveolar/metabolismo , Perda do Osso Alveolar/patologia , Animais , Osso e Ossos/efeitos dos fármacos , Catepsina K/biossíntese , Humanos , Dente Molar/metabolismo , Dente Molar/patologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Ratos , Reabsorção da Raiz/metabolismo , Reabsorção da Raiz/patologia , Técnicas de Movimentação Dentária , Microtomografia por Raio-X
18.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 59(9): 886-891, 2024 Sep 09.
Artigo em Chinês | MEDLINE | ID: mdl-39289975

RESUMO

Early orthodontic treatment is an important means of preventing and treating dentofacial deformities during the period of growth and development. In this stage, children have great potential in growth and development, high adaptability of muscles and temporomandibular joint, and good responsiveness to orthodontic force. Therefore, orthodontic intervention and treatment in this stage can prevent and guide the normal growth and development of dentition, occlusion and maxillofacial complex. This article summarizes the commonly used orthodontic techniques and appliances in the mixed dentition, including interceptive treatment of oral habits, application of functional appliances, fixed appliances, clear aligners, as well as management of severe crowding and space maintenance. This article comprehensively explains the application and indications of different orthodontic techniques in design and appliance selection in the treatment of malocclusions in the mixed dentition.


Assuntos
Dentição Mista , Má Oclusão , Humanos , Má Oclusão/terapia , Criança , Aparelhos Ortodônticos Fixos , Aparelhos Ortodônticos Funcionais , Ortodontia Corretiva/métodos , Ortodontia Interceptora , Desenho de Aparelho Ortodôntico
19.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 59(9): 904-910, 2024 Sep 09.
Artigo em Chinês | MEDLINE | ID: mdl-39289978

RESUMO

Objective: To compare the clinical efficacy of customized titanium plate and conventional maxillary protraction treatment in patients with skeletal class Ⅲ malocclusion during growth spurt. Methods: During growth spurt, skeletal class Ⅲ patients with maxillary hypoplasia who were treated in the Department of Orthodontics, Capital Medical University School of Stomatology from August 2018 to July 2021 were prospectively enrolled. They were treated with maxillary protraction using customized titanium plates (customized titanium plate group) and conventional methods (conventional protraction group), respectively. Lateral cephalometric radiographs were collected before and after treatment for conventional cephalometric analysis, including SNA angle (angle between Sella, Nasion and A point), ANB angle (angle between A point, Nasion, and B point), FH-MP angle (mandibular plane angle), Y-axis angle, U1-L1 angle (upper to lower central incisor angle), U1-SN angle (upper incisor to SN plane angle), anterior and lower height, maxillary length, etc. The stable basicranial line (SBL) was used as the reference line to measure the distance from each reference point (ANS point, A point, Prn point, Sn point, UL point etc.) to the stable basicranial vertical line (VerT, the perpendicular line of the skull base line at the intersection point of the anterior wall of the sella image and the inferior edge of the anterior bed process). Paired t-tests were performed on the cephalometric data before and after maxillary protraction treatment in the two groups, and two independent samples t-tests were performed to compare the differences in the efficacy of the two maxillary protraction methods. Results: A total of 20 patients (9 males and 11 females), aged (10.8±1.3) years, were included in the personalized titanium plate group. A total of 20 patients (8 males and 12 females), aged (10.5±1.1) years, were included in the conventional protraction group. The SNA angle, ANB angle, FH-MP angle, Y-axis angle, anterior lower height, maxillary length, ANS-VerT distance, A-VerT distance, Prn-VerT distance, Sn-VerT distance, and UL-VerT distance were significantly higher than those before treatment in the two groups (P<0.05). The changes of SNA angle, ANB angle and A-VerT before and after treatment in the personalized titanium plate group [3.15°±2.28°, 4.64°±1.40°, (4.41±3.43) mm, respectively] were significantly higher than those in the traditional group [2.13°±2.69°, 2.81°±1.10°, (3.13±4.76) mm, respectively](P<0.05), and the changes of U1-L1 angle and U1-SN angle before and after treatment (-0.76°±7.42° and 1.74°±6.38°, respectively) was significantly lower than that of the control group (-5.14°±6.62° and 4.57°±5.24°, respectively, P<0.05). Conclusions: Maxillary protraction can effectively improve skeletal class Ⅲ relationships in growing patients. The linear measurements using the SBL line as a reference plane visualize the sagittal improvement in sagittal relationship after maxillary protraction. The customized titanium plate maxillary protraction treatment has a clear therapeutic effect on patients with skeletal class Ⅲ deformities, and its dental effect is relatively small.


Assuntos
Placas Ósseas , Cefalometria , Má Oclusão Classe III de Angle , Maxila , Titânio , Humanos , Maxila/crescimento & desenvolvimento , Estudos Prospectivos , Má Oclusão Classe III de Angle/terapia , Mandíbula
20.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 59(10): 977-987, 2024 Sep 27.
Artigo em Chinês | MEDLINE | ID: mdl-39344448

RESUMO

Temporomandibular joint (TMJ) diseases are common clinical conditions. The number of patients with TMJ diseases is large, and the etiology, epidemiology, disease spectrum, and treatment of the disease remain controversial and unknown. To understand and master the current situation of the occurrence, development and prevention of TMJ diseases, as well as to identify the patterns in etiology, incidence, drug sensitivity, and prognosis is crucial for alleviating patients'suffering.This will facilitate in-depth medical research, effective disease prevention measures, and the formulation of corresponding health policies. Cohort construction and research has an irreplaceable role in precise disease prevention and significant improvement in diagnosis and treatment levels. Large-scale cohort studies are needed to explore the relationship between potential risk factors and outcomes of TMJ diseases, and to observe disease prognoses through long-term follw-ups. The consensus aimsto establish a standard conceptual frame work for a cohort study on patients with TMJ disease while providing ideas for cohort data standards to this condition. Temporomandibular joint disease cohort data consists of both common data standards applicable to all specific disease cohorts as well as disease-specific data standards. Common data were available for each specific disease cohort. By integrating different cohort research resources, standard problems or study variables can be unified. Long-term follow-up can be performed using consistent definitions and criteria across different projects for better core data collection. It is hoped that this consensus will be facilitate the development cohort studies of TMJ diseases.

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