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1.
Nan Fang Yi Ke Da Xue Xue Bao ; 41(11): 1631-1640, 2021 Nov 20.
Artigo em Chinês | MEDLINE | ID: mdl-34916188

RESUMO

OBJECTIVE: To identify the key hub genes in prostate cancer metastasis based on weighted gene co-expression network analysis (WGCNA) and verify the identified genes. METHODS: Whole-genome chip data GSE6919 of prostate cancer study were analyzed using principal component analysis (PCA), and the differentially expressed genes (DEGs) were analyzed using R software. WGCNA was performed to construct a gene co-expression network for screening the key genes. TCGA database was used to explore the expressions of the DEGs and their association with the prognosis. To validate the results, we designed siRNA fragments targeting the metastasis-related gene HNRNPA2B1, and observed its effect on growth, apoptosis, clone formation, migration and invasion of prostate cancer cell lines using MTT assay, flow cytometry, clone formation assay, and Transwell assay. RESULTS: PCA analysis showed obvious clustering of significant DEGs in metastatic cancer group. The modules obtained by WGCNA analysis in metastasis group involved stem cell differentiation, amino acid metabolism and immune response. Further screening of the genes identified 3 genes related with prostate cancer occurrence (BDH1, PAK4 and EXTL3) and another 3 with prostate cancer metastasis (NKTR, CTBP2 and HNRNPA2B1), which were shown to have differential expressions in TCGA database and were correlated with the patient's overall survival. In the cell experiment, PC3 and LNCap cells transfected with the siRNA fragment targeting HNRNPA2B1 showed obvious growth inhibition with increased cell apoptosis, lowered clone formation ability, and suppressed capacities for migration and invasion. CONCLUSION: We identified 3 hub genes related with the occurrence (BDH1, PAK4 and EXTL3) and another 3 with metastasis of prostate cancer (NKTR, CTBP2 and HNRNPA2B1) using WGCNA, which provides a new approach for studying the regulatory mechanisms of prostate cancer.


Assuntos
Neoplasias da Próstata , Oxirredutases do Álcool/genética , Proteínas Correpressoras/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo A-B/genética , Humanos , Hidroxibutirato Desidrogenase/genética , Masculino , N-Acetilglucosaminiltransferases/genética , Prognóstico , Neoplasias da Próstata/genética , Receptores Imunológicos/genética , Quinases Ativadas por p21/genética
2.
Zhonghua Zhong Liu Za Zhi ; 43(11): 1148-1155, 2021 Nov 23.
Artigo em Chinês | MEDLINE | ID: mdl-34794216

RESUMO

Objective: To investigate the effects of lncRNA LINC00839 on the proliferation, migration and invasion of hepatocellular carcinoma cells and its mechanism. Methods: Real-time quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of LINC00839 and miR-3666 in hepatocellular carcinoma tissues and adjacent tissues. Pearson correlation was used to analyze the correlation between LINC00839 and miR-3666 expression in liver cancer tissues. Hepatocellular carcinoma cells MHCC97H were cultured in vitro and divided into si-NC group, si-LINC00839 group, miR-NC group, miR-3666 group, si-LINC00839+ anti-miR-NC group, and si-LINC00839+ anti-miR-3666 group. Methylthiazoletrazolium (MTT) method and clone formation experiment were used to detect cell proliferation. Transwell array was used to detect the cell migration and invasion. Western blot was used to detect the protein expressions of p21, E-cadherin and MMP-2. The double luciferase reporter gene experiment was used to verify the regulatory relationship between LINC00839 and miR-3666. Results: Compared with adjacent tissues, the expression level of LINC00839 in hepatocellular carcinoma tissues increased (2.82±0.27 vs. 0.96±0.10, P<0.001), but the expression level of miR-3666 decreased (0.23±0.02 vs. 1.01±0.10, P<0.001). The expression levels of LINC00839 and miR-3666 in liver cancer tissue were negatively correlated (r=-0.658, P<0.001). The survival rate of MHCC97H cells in the si-LINC00839 group [(53.91±5.41)% vs. (100.53±10.22)%], the number of clones formed (92.0±8.0 vs. 164.0±14.3), the number of migration (131.0±12.7 vs. 247.0±22.4), the number of invasion (66.0±6.4 vs. 120.0±11.6) and the protein level of MMP-2 (0.20±0.02 vs. 0.67±0.06) were lower than those in the si-NC group (P<0.001). However, the protein levels of p21 (0.76±0.07 vs. 0.25±0.02) and E-cadherin (0.78±0.08 vs. 0.14±0.01) were higher than those in the si-NC group (P<0.001). LINC00839 targeted and negatively regulated the expression of miR-3666. The survival rate of MHCC97-H cells in the miR-3666 group [(47.93±4.86)% vs. (100.11±10.21)%], the number of clone formation (78.0±7.7 vs. 166.0±15.9), the number of migration (117.0±12.1 vs. 250.0±25.0), the number of invasion (57.0±5.7 vs. 121.0±12.3) and the protein level of MMP-2 (0.16±0.01 vs. 0.69±0.07) were lower than those in the miR-NC group (all P<0.001). However, the protein levels of p21 (0.83±0.08 vs. 0.24±0.02) and E-cadherin (0.87±0.09 vs. 0.13±0.01)were higher than those in the miR-NC group (all P<0.001). The survival rate of MHCC97-H cells in the si-LINC00839+ anti-miR-3666 group [(89.94±9.05)% vs. (54.12±5.39)%], the number of clones (143.0±13.8 vs. 94.0±9.4), the number of migration (208.0±19.8 vs. 129.0±12.6), the number of invasion (108.0±10.1 vs. 65.0±6.4) and the protein level of MMP-2 (0.31±0.03 vs 0.66±0.06) were higher than those in the si-LINC00839+ anti-miR-NC group (P<0.001). However, the protein levels of p21 (0.31±0.03 vs. 0.74±0.07) and E-cadherin (0.28±0.03 vs. 0.80±0.08) were lower than those int the si-LINC00839+ anti-miR-NC group (P<0.001). Conclusion: Inhibition of LINC00839 expression may inhibit the proliferation, migration and invasion of hepatocellular carcinoma cells by targeting up-regulation of miR-3666 expression.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , MicroRNAs/genética
3.
Zhonghua Yi Xue Za Zhi ; 101(42): 3459-3465, 2021 Nov 16.
Artigo em Chinês | MEDLINE | ID: mdl-34775702

RESUMO

Objective: To estimate the prevalence of hyperkalemia and hypokalemia in patients with chronic kidney disease (CKD), analyze the influencing factors and explore the impact on disease prognosis. Methods: A total of 3 190 patients with CKD stage 1-4 from 39 tertiary clinical centers in China between November 2011 and December 2016 were recruited. The baseline characteristics of the patients were collected through face-to-face questionnaire investigation, physical examination and laboratory test. Meanwhile, the data of patient's end-stage renal disease, cardiovascular disease events and deaths were obtained up to December 2017 through active monitoring. The patients were categorized into three groups based on their baseline level of serum potassium (hypokalemia:<3.5 mmol/L, normal range: 3.5-<5.0 mmol/L, hyperkalemia: ≥5 mmol/L). Multi-nominal logistic regression was employed to evaluate the association between clinical characteristics and the presence of hyperkalemia or hypokalemia. The competing risk-based subdistribution Cox proportional hazards regression was used to assess the association between baseline level of serum potassium and various outcomes. Results: The mean age of the patients was (50±14) years, with a male rate of 57.6% (1 839/3 190) and a majority of glomerulonephritis (59.7%, 1 668/2 792). Patients with CKD stage 3-4 accounted for 70.8% (2 260/3 190), and the mean level of serum potassium was (4.4±0.7) mmol/L. The prevalence of hypokalemia and hyperkalemia was 3.7% (n=118) and 17.6% (n=561), respectively. In the multivariable adjusted analysis, presence of history of cardiovascular disease (OR=0.33, 95%CI: 0.13-0.83, P=0.019) and estimated glomerular filtration rate (OR=0.95, 95%CI: 0.91-0.98, P=0.001) were inversely associated with hypokalemia, while use of thiazide or loop diuretic (OR=2.06, 95%CI: 1.51-2.81, P<0.001) and estimated glomerular filtration rate (OR=1.13, 95%CI: 1.12-1.16, P<0.001) were positively associated with hyperkalemia. After adjusting for relevant cardiovascular and renal risk factors, the result only showed a significant association between hypokalemia and risk of all-cause mortality (HR=2.12, 95%CI: 1.06-4.24, P=0.034). Conclusions: Hypokalemia and hyperkalemia were not rare in patients with CKD in China, with the latter more prevalent. Hypokalemia was independently associated with the risk of death.


Assuntos
Hiperpotassemia , Insuficiência Renal Crônica , Adulto , Humanos , Hiperpotassemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Potássio , Prevalência , Prognóstico , Insuficiência Renal Crônica/epidemiologia
4.
Neurologia (Engl Ed) ; 2021 Sep 09.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34511274

RESUMO

PURPOSE: To investigate the effect of endovascular embolization of posterior communicating artery (Pcom) aneurysms on concomitant oculomotor nerve palsy (OMNP) and factors affecting the effect of treatment. MATERIALS AND METHODS: Patients with the Pcom aneurysms concomitant with OMNP were retrospectively enrolled for endovascular treatment of the aneurysms. All patients had the endovascular management. The clinical effect, degree of OMNP, size of the aneurysm, type of treatment, subarachnoid hemorrhage (SAH), and time from onset to treatment were analyzed on the resolution of OMNP. RESULTS: Ninety-six patients with 99 Pcom aneurysms were enrolled and treated endovascularly, with the success rate of 100%. Immediately after endovascular treatment, 75 aneurysms (75.75%) got complete occlusion, and 24 (24.24%) nearly complete occlusion. Followed up for 3-18 (mean 8.52±0.56) months, complete resolution of the OMNP was achieved in 63 patients (65.63%), partial resolution in 21 (21.88%), and non-recovery in the other 12 (12.50%). The degree of OMNP at onset, SAH, and time from onset to treatment were significantly (P<0.05) correlated with the resolution of OMNP. Univariate analysis revealed that younger age of the patient, degree of OMNP at onset, presence of subarachnoid hemorrhage, and time from disease onset to treatment were significantly (P<0.05) associated with the recovery of OMNP. Multivariate analysis revealed that the younger age, degree of OMNP at onset, and time from disease onset to treatment were significantly (P<0.05) associated with the recovery of OMNP. CONCLUSION: Endovascular embolization of Pcom aneurysms concomitant with OMNP can effectively improve the OMNP symptoms, especially for patients with moderate and a shorter history of OMNP. Younger age, degree of oculomotor nerve palsy at onset, and time from onset to treatment may significantly affect recovery of oculomotor nerve palsy.

5.
Ultramicroscopy ; 230: 113370, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34418774

RESUMO

An atomic potential should be assigned to several slices in the multislice method owing to its three-dimensional (3D) distribution. Based on a formula including several Gaussian functions to fit electron atomic scattering factors, a simple analytical expression is proposed to calculate the potential of atoms projected onto multiple slices. The potential in 3D distribution is properly projected onto slices that do not contain the atomic centroid. Thus, the fluctuations in atomic altitude influence the assigning of atomic potentials is considered correctly. The projected potential is calculated in a reciprocal space and involves an accurate 3D atomic position. Tests conducted with a plausible Ag chain verify the good performance of this new approach. The simulated exit wave leaving a complex crystal of Ba6Nd2Ti4O17 demonstrates that the proposed simulation approach is better than the traditional multislice method.

6.
Artigo em Chinês | MEDLINE | ID: mdl-34365762

RESUMO

Objective: To compare the quality of life of pneumoconiosis patients between from rural migrant workers and from a state-owned enterprises in Zhaotong City Yunnan Province, and to explore the factors influencing quality of life of pneumoconiosis patients. Methods: In August 2017, 83 patients from rural migrant workers in Zhaotong City Yunnan Province and 126 pneumoconiosis patients from a state-owned coal mining enterprises were selected as target population. World Health Organization on Quality of Life Brief Scale (WHOQOL-BREF) and self-designed questionnaires were used to collect information from two groups. The demographic information, health status and quality of life of two groups were compared. The factors influencing quality of life were analyzed by multi-liner regression analyses. Results: Average annual household income of rural migrant workers group was lower than that of state-owned enterprises group, and the average annual household expenditure for health of rural migrant workers group was higher than that of state-owned enterprises group (P<0.01) . Overall score of WHOQOL-BREF and scores for four domains including physiology, psychology, social relationship and environment of rural migrant workers group were lower than the scores of patients from state-owned enterprises group (P<0.01) . The result of multi-liner regression analysis showed that average annual household income (b=0.00015, 95%CI: 0.00010-0.00020) , being rural migrant workers (b=-5.904, 95%CI: -8.436--3.372) , better action ability (b=2.595, 95%CI: 0.706-4.483) and have complication (b=-2.542, 95%CI: -4.698--0.387) were factors influencing overall score of WHOQOL-BREF of pneumoconiosis patients (P<0.05) . Conclusion: The quality of life of pneumoconiosis patients from rural migrant workers is lower than that from state-owned enterprises. And the average annual household income, action ability and having complication or not are factors influencing the quality of life of pneumoconiosis patients.


Assuntos
Minas de Carvão , Pneumoconiose , Migrantes , China , Humanos , Qualidade de Vida , Inquéritos e Questionários
7.
Science ; 373(6553): 425-430, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34261813

RESUMO

The Crab Nebula is a bright source of gamma rays powered by the Crab Pulsar's rotational energy through the formation and termination of a relativistic electron-positron wind. We report the detection of gamma rays from this source with energies from 5 × 10-4 to 1.1 peta-electron volts with a spectrum showing gradual steepening over three energy decades. The ultrahigh-energy photons imply the presence of a peta-electron volt electron accelerator (a pevatron) in the nebula, with an acceleration rate exceeding 15% of the theoretical limit. We constrain the pevatron's size between 0.025 and 0.1 parsecs and the magnetic field to ≈110 microgauss. The production rate of peta-electron volt electrons, 2.5 × 1036 ergs per second, constitutes 0.5% of the pulsar spin-down luminosity, although we cannot exclude a contribution of peta-electron volt protons to the production of the highest-energy gamma rays.

8.
Int J Implant Dent ; 7(1): 65, 2021 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-34291352

RESUMO

BACKGROUND: Zygomatic implants have been described as a therapeutic alternative for patients with severe maxillary atrophy in order to avoid bone augmentation procedures. Taking that into account, in these treatments, the key factor is the position of the implant, the virtual surgical planning (VSP) is widespread among most clinicians before surgery on the patient. However, there are no studies which evaluate the clinical relevance of these VSP. The aim of this study is to determine whether digital planning on zygomatic implants has any influence on the implant dimensions and position, even when performing conventional surgery afterwards. RESULTS: Fourteen zygomatic implants were placed in four patients. Pre-operative and post-operative helicoidal computed tomography were performed to each patient to allow the comparison between the digital planning and the final position of implants. Tridimensional deviation (TD), mesio-distal deviation (MDD), bucco-palatine deviation (BPD), and apico-coronal deviation (ACD) were evaluated as well as angular deviation (AD). Significative differences in apical TD were observed with a mean of 6.114 ± 4.28 mm (p < 0.05). Regarding implant position, only implants placed in the area of the first right molar reported significant differences (p < 0.05) for ACD. Also, implant length larger than 45 mm showed BPD significative differences (p < 0.05). CONCLUSIONS: Zygomatic implant surgery is a complex surgical procedure, and although VSP is a useful tool which helps the clinician determine the number and the length of zygomatic implants as well as its proper position, surgical experience is still mandatory.


Assuntos
Maxila , Zigoma , Atrofia/patologia , Humanos , Maxila/diagnóstico por imagem , Próteses e Implantes , Tomografia Computadorizada por Raios X , Zigoma/diagnóstico por imagem
9.
Hum Exp Toxicol ; 40(12_suppl): S77-S86, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34219538

RESUMO

Asthma is a respiratory disease with a clinically high incidence, and repeated attacks of asthma severely affect the quality of life and even pose a threat to health, leading to severe burdens on families and even the society. A thorough understanding of the pathogenesis of asthma is essential for the prevention and treatment of asthma. This study aimed to examine the effect of the microRNA miR-27a on asthma and its relationship with mitogen activated protein kinase 4 (MAP2K4). Patients with asthma admitted to our hospital from August 2016 to August 2018 and healthy participants in the same period were included in this prospective analysis. The mRNA expression levels of miR-27a and MAP2K4 in peripheral blood were determined. Airway smooth muscle cells (ASMCs) were used to study the effects of miR-27a and MAP2K4 on cell biological behavior. The relationship between miR-27a and MAP2K4 was verified using dual-luciferase reporter assay. miR-27a expression was increased and MAP2K4 mRNA expression was decreased in asthma (P < 0.05). Increasing miR-27a expression and inhibiting MAP2K4 expression could enhance the activity of ASMCs, whereas inhibiting miR-27a expression and increasing MAP2K4 expression had the opposite effect (P < 0.05). Dual-luciferase reporter assay results showed that the fluorescence activity of MAP2K4-wild type was inhibited by increased miR-27a expression (P < 0.05). miR-27a promotes the proliferation and invasion of ASMCs by targeting MAP2K4 and is involved in the occurrence of asthma.

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.
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.

12.
Zhonghua Yi Xue Za Zhi ; 101(18): 1363-1368, 2021 May 18.
Artigo em Chinês | MEDLINE | ID: mdl-34015871

RESUMO

Objective: To investigate the effect of serum potassium level and hyperkalemia on the renal function decline in chronic kidney disease (CKD) patients. Methods: The clinical data at baseline and follow-up in stage Ⅲ-Ⅴ CKD patients without dialysis who were followed up for more than one year in Tianjin First Central Hospital from May 2015 to June 2019 and Teikyo University School of Medicine from January 2008 to July 2013 were retrospectively collected. All patients were divided into stable group (337 cases), slow progression group (337 cases) and rapid progression group (338 cases) according to the tertile of estimated glomerular filtration rate (eGFR) slope (the annual average percentage of eGFR decline). Multivariate logistic regression analysis models were used to evaluate the correlations of baseline serum potassium or time-averaged serum potassium level with CKD rapid progression. Results: Three hundred and forty-three cases from Tianjin First Central Hospital and 669 cases from Teikyo University School of Medicine were included in the study, and 635 cases (62.7%) were male. The average age was (61±14) years old and the average eGFR decline slope was 4.0%/year. The levels of baseline serum potassium and time-averaged serum potassium of patients in the slow progression group [(4.47±0.52) and (4.51±0.43) mmo/L] and rapid progression group [(4.62±0.62) and (4.76±0.48) mmo/L] were higher than those in the stable group [(4.37±0.49) and (4.38±0.37) mmo/L] (both P<0.05). Meanwhile, 24.6% (83/338) of the patients in the rapid progression group had hyperkalemia at baseline (serum potassium ≥5.0 mmol/L) and 34.9% (118/338) of the patients had time-averaged serum potassium ≥5.0 mmol/L, which were higher than those in the stable group [10.7% (36/337) and 6.5% (22/337)] (both P<0.001). Multivariate logistic regression analysis showed that compared with the stable group, baseline serum potassium (OR=1.843, 95%CI: 1.051-3.234) and time-averaged serum potassium (OR=2.495, 95%CI: 1.040-5.987) were correlated with the rapid progression of CKD. Time-averaged serum potassium ≥5.0 mmol/L was the independent influencing factor for rapid progression of CKD. Conclusions: During the follow-up period, the average level of serum potassium in stage Ⅲ-Ⅴ CKD patients should be controlled under 5.0 mmol/L, which may reduce the risk of rapid decline of renal function.


Assuntos
Diálise Renal , Insuficiência Renal Crônica , Idoso , Progressão da Doença , Feminino , Taxa de Filtração Glomerular , Humanos , Masculino , Pessoa de Meia-Idade , Potássio , Estudos Retrospectivos , Fatores de Risco
13.
Phys Rev Lett ; 126(15): 152701, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33929230

RESUMO

The discrepancy between observations from γ-ray astronomy of the ^{60}Fe/^{26}Al γ-ray flux ratio and recent calculations is an unresolved puzzle in nuclear astrophysics. The stellar ß-decay rate of ^{59}Fe is one of the major nuclear uncertainties impeding us from a precise prediction. The important Gamow-Teller strengths from the low-lying states in ^{59}Fe to the ^{59}Co ground state are measured for the first time using the exclusive measurement of the ^{59}Co(t,^{3}He+γ)^{59}Fe charge-exchange reaction. The new stellar decay rate of ^{59}Fe is a factor of 3.5±1.1 larger than the currently adopted rate at T=1.2 GK. Stellar evolution calculations show that the ^{60}Fe production yield of an 18 solar mass star is decreased significantly by 40% when using the new rate. Our result eliminates one of the major nuclear uncertainties in the predicted yield of ^{60}Fe and alleviates the existing discrepancy of the ^{60}Fe/^{26}Al ratio.

14.
AJNR Am J Neuroradiol ; 42(7): 1208-1215, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33858820

RESUMO

BACKGROUND AND PURPOSE: The clinical practice of three-dimensional TOF-MRA, despite its capability in brain artery assessment, has been hampered by the relatively long scan time, while recent developments in fast imaging techniques with random undersampling has shed light on an improved balance between image quality and imaging speed. Our aim was to evaluate the effectiveness of TOF-MRA accelerated by compressed sensitivity encoding and to identify the optimal acceleration factors for routine clinical use. MATERIALS AND METHODS: One hundred subjects, enrolled at 5 centers, underwent 8 brain TOF-MRA sequences: 5 sequences using compressed sensitivity encoding with acceleration factors of 2, 4, 6, 8, and 10 (CS2, CS4, CS6, CS8, and CS10), 2 using sensitivity encoding with factors of 2 and 4 (SF2 and SF4), and 1 without acceleration as a reference sequence (RS). Five large arteries, 6 medium arteries, and 6 small arteries were evaluated quantitatively (reconstructed signal intensity, structural similarity, contrast ratio) and qualitatively (scores on arteries, artifacts, overall image quality, and diagnostic confidence for aneurysm and stenosis). Comparisons were performed among the 8 sequences. RESULTS: The quantitative measurements showed that the reconstructed signal intensities of the assessed arteries and the structural similarity consistently decreased as the compressed sensitivity encoding acceleration factor increased, and no significant difference was found for the contrast ratios in pair-wise comparisons among SF2, CS2, and CS4. Qualitative evaluations showed no significant difference in pair-wise comparisons among RS, SF2, and CS2 (P > .05). The visualization of all the assessed arteries was acceptable for CS2 and CS4, while 2 small arteries in images of CS6 were not reliably displayed, and the visualization of large arteries was acceptable in images of CS8 and CS10. CONCLUSIONS: CS4 is recommended for routine brain TOF-MRA with balanced image quality and acquisition time; CS6, for examinations when small arteries are not evaluated; and CS10, for fast visualization of large arteries.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Transtornos Cerebrovasculares , Angiografia por Ressonância Magnética , Aceleração , Adulto , Idoso , Idoso de 80 Anos ou mais , Artefatos , Transtornos Cerebrovasculares/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Angiografia por Ressonância Magnética/instrumentação , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Adulto Jovem
15.
Neurologia (Engl Ed) ; 2021 Apr 19.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33888329

RESUMO

PURPOSE: The performance of the Low-Profile Visualized Intraluminal Support (LVIS) stent deployed following balloon angioplasty is unknown in treating intracranial atherosclerotic stenosis, and this study was to investigate the safety and efficacy of the LVIS stent in treating intracranial atherosclerotic stenosis in the middle cerebral artery M1 segment. METHODS: Thirty-five patients were enrolled with 35 atherosclerotic stenoses at the M1 segment. The stenosis was about 75% in 16 patients, 80% in 15, and 90% in the rest four. The LVIS stent was used to treat these patients. RESULTS: The success rate of stenting was 97.1%. The stenting procedure was failed in one patient because of intraprocedural dissection of the stenotic (75%) segment, resulting in a 30-day periprocedural complication rate of 2.9% (1/35). Before stenting, the stenosis rate ranged 75%-90% (mean 78.9%±4.7%), and after stenting, the diameter of the stented segment was significantly (P<0.0001) increased to 1.5-3.4mm (mean 2.1±0.32mm) ranging 68.2%-100% (mean 94.0%±5.8%) of the normal arterial diameter, with the residual stenosis ranging 0-31.8% (median 4.8%, IQR 2.4%-7.3%). Follow-up was performed at 6-20 months (mean 8.5) after stenting. One patient (2.9%) had occlusion of the stented M1 segment with no symptoms, and two patients (5.7%) had slight asymptomatic instent stenosis (40%) at the M1 segment, with the instent restenosis and occlusion rate of 8.6% (3/35). CONCLUSION: The braided LVIS stent can be safely applied for treatment of intracranial atherosclerotic stenosis in the middle cerebral artery with good safety and efficacy immediately after stenting and at follow-up.

16.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(3): 371-378, 2021 Mar 06.
Artigo em Chinês | MEDLINE | ID: mdl-33730830

RESUMO

Objective: To explore the flora characteristics and differences of esophageal tissues between elderly esophageal squamous cell carcinoma (ESCC) patients and young and middle-aged ESCC patients, so as to assist in studying the potential biomarkers of elderly ESCC patients. Methods: In this study, a retrospective study was adopted. 72 ESCC patients diagnosed in Taihe Hospital, Shiyan City, Hubei Province from July 2018 to July 2019 were selected, including 49 patients in the elderly group (≥ 60 years old, 40 males and 9 females), 23 patients in the young and middle-aged group (<60 years old, 21 males and 2 females). In the same period, 20 healthy persons without abnormal gastroscopy in endoscopy center were selected as the control group (aged 35-78 years old, median age 57 years old, 16 males and 4 females). The genomic DNA was extracted from the affected esophageal tissues of patients with ESCC and the middle esophageal samples of the control group. The V4 hypervariable region of bacterial 16SrRNA gene sequence was amplified. Illumina HiSeq sequencing technology was adopted. The flora characteristics of elderly, young and middle-aged ESCC patients was compared and analyzed. QIIME and Rstudio software were used to analyze the sequence data, and nonparametric Kruskal-Wallis test or Wilcoxon rank sum test were used for statistical methods. Results: Shannon index [5.17 (4.53, 5.95) vs. 4.79 (3.74, 5.97)], Simpson index [0.94 (0.91, 0.96) vs. 0.92 (0.83, 0.96)] and Chao1 index [343.55 (259.76, 570.59) vs. 329.16 (268.88, 648.00)] were similar in flora of two groups, and there was no significant difference (Z=-0.791, -1.057, -0.380, all P>0.05). There was no significant difference in ß-diversity between the elderly group and the young and middle-aged group (PC1=19.14%, PC2=6.95%, PPC1=0.67, PPC2=0.42). At the phyla level, the top 5 phyla in abundance were as follows: Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria and Fusobacteria in the young and middle-aged group, while the top 5 phyla in abundance were as follows: Firmicutes, Bacteroidetes, Proteobacteria, Fusobacteria and Actinobacteria in the elderly group; the significant difference between the two groups was Fusobacteria (Q=0.596, P<0.05). At the genus level, the top 5 genera in the young and middle-aged group in abundance were as follows: Prevotella, Bacteroides, Streptococcus, Selenomonas and Veillonella. In the elderly group, Prevotella, Bacteroides, Streptococcus, Selenomonas and Haemophilus were the top 5 in abundance, and there were significant difference in Fusobacterium between the two groups (Q=0.938, P<0.05). PICRUSt function prediction showed that the abundance of Aminoacyl.tRNA.biosynthesis, Nucleotide.excision.repair, RNA.polymerase, Ribosome, Clavulanic.acid.biosynthesis, Photosynthesis and Photosynthesis. proteins in the elderly group were lower than those in the young and middle-aged group (all Q=0.734, P<0.05). Conclusion: There is no significant difference in α-diversity and ß-diversity between elderly ESCC patients and young and middle-aged patients, but the abundance of Fusobacterium flora increased.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Adulto , Idoso , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas do Esôfago/genética , Feminino , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Estudos Retrospectivos
18.
Phys Rev Lett ; 126(1): 017201, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33480800

RESUMO

We apply neutron spectroscopy to measure the magnetic dynamics in the S=3/2 magnet ß-CaCr_{2}O_{4} (T_{N}=21 K). The low-energy fluctuations, in the ordered state, resemble large-S linear spin waves from the incommensurate ground state. However, at higher energy transfers, these semiclassical and harmonic dynamics are replaced by an energy and momentum broadened continuum of excitations. Applying kinematic constraints required for energy and momentum conservation, sum rules of neutron scattering, and comparison against exact diagonalization calculations, we show that the dynamics at high-energy transfers resemble low-S one-dimensional quantum fluctuations. ß-CaCr_{2}O_{4} represents an example of a magnet at the border between classical Néel and quantum phases, displaying dual characteristics.

19.
J Appl Microbiol ; 130(6): 2008-2017, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32358825

RESUMO

AIMS: To identify a lambda promoter pL mutant that could extend the thermal stability of the thermo-inducible λcI857-pR/pL system and to evaluate the effects of the modified system for the controlled expression of lysis gene E during the production of bacterial ghosts (BGs). METHODS AND RESULTS: The promoter pL mutant was identified by random mutagenesis and site-directed mutagenesis. The results showed that a T â†’ 35C mutation in the pL promoter was responsible for the phenotype alteration. Under the same induction conditions, the lysis rates of the modified lytic system on Escherichia coli and Salmonella enteritidis were significantly lower than that of the control, while the lysis rates of Escherichia coli with the thermo-inducible lytic system were significantly higher than that of S. enteritidis with the corresponding plasmid (P < 0·05). CONCLUSIONS: Increasing the heat stability of the thermo-inducible lytic systems decreased lysis efficiency during the production of BGs. There exist differences in the lysis efficiency of thermo-inducible lytic systems between different bacterial strains. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings enrich current knowledge about modifications to thermo-inducible systems and provide a reference for the application of these modified systems for the production of BGs and controlled gene expression in bacteria.


Assuntos
Bacteriófago lambda/fisiologia , Regulação Viral da Expressão Gênica , Regiões Promotoras Genéticas/genética , Proteínas Virais/genética , Bacteriólise , Bacteriófago lambda/genética , Escherichia coli/fisiologia , Escherichia coli/virologia , Mutação , Plasmídeos/genética , Plasmídeos/fisiologia , Salmonella enteritidis/fisiologia , Salmonella enteritidis/virologia , Temperatura
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