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1.
Nature ; 606(7915): 678-682, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35732764

RESUMO

A long-standing question in nuclear physics is whether chargeless nuclear systems can exist. To our knowledge, only neutron stars represent near-pure neutron systems, where neutrons are squeezed together by the gravitational force to very high densities. The experimental search for isolated multi-neutron systems has been an ongoing quest for several decades1, with a particular focus on the four-neutron system called the tetraneutron, resulting in only a few indications of its existence so far2-4, leaving the tetraneutron an elusive nuclear system for six decades. Here we report on the observation of a resonance-like structure near threshold in the four-neutron system that is consistent with a quasi-bound tetraneutron state existing for a very short time. The measured energy and width of this state provide a key benchmark for our understanding of the nuclear force. The use of an experimental approach based on a knockout reaction at large momentum transfer with a radioactive high-energy 8He beam was key.

2.
Zhonghua Xin Xue Guan Bing Za Zhi ; 52(2): 137-143, 2024 Feb 24.
Artigo em Zh | MEDLINE | ID: mdl-38326064

RESUMO

Objective: To explore the long-term effects of intravascular ultrasound (IVUS) guidance on patients with acute coronary syndrome (ACS) undergoing drug-eluting stents (DES) implantation. Methods: Data used in this study derived from ULTIMATE trial, which was a prospective, multicenter, randomized study. A total of 1 448 all-comer patients were enrolled between 2014 August and 2017 May. Primary endpoint of this study was target vessel failure (TVF) at 3 years, including cardiac death, target-vessel-related myocardial infarction, and clinically-driven target vessel revascularization. Results: ACS was present in 1 136 (78.5%) patients, and 3-year clinical follow-up was available in 1 423 patients (98.3%). TVF in the ACS group was 9.6% (109/1 136), which was significantly higher than 4.5% (14/312) in the non-ACS group (log-rank P=0.005). There were 109 TVFs in the ACS patients, with 7.6% (43/569) TVFs in the IVUS group and 11.6% (66/567) TVFs in the angiography group (log-rank P=0.019). Moreover, patients with optimal IVUS guidance were associated with a lower risk of 3-year TVF compared to those with suboptimal IVUS results (5.4% (16/296) vs. 9.9% (27/273),log-rank P=0.041). Conclusions: This ULTIMATE-ACS subgroup analysis showed that ACS patients undergoing DES implantation were associated with a higher risk of 3-year TVF. More importantly, the risk of TVF could be significantly decreased through IVUS guidance in patients with ACS, especially in those who had an IVUS-defined optimal procedure.


Assuntos
Síndrome Coronariana Aguda , Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Humanos , Angiografia Coronária , Síndrome Coronariana Aguda/cirurgia , Estudos Prospectivos , Resultado do Tratamento , Intervenção Coronária Percutânea/métodos , Ultrassonografia de Intervenção/efeitos adversos , Ultrassonografia de Intervenção/métodos
3.
Phys Rev Lett ; 131(22): 222502, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101341

RESUMO

Collinear laser spectroscopy was performed on the isomer of the aluminium isotope ^{26m}Al. The measured isotope shift to ^{27}Al in the 3s^{2}3p ^{2}P_{3/2}^{○}→3s^{2}4s ^{2}S_{1/2} atomic transition enabled the first experimental determination of the nuclear charge radius of ^{26m}Al, resulting in R_{c}=3.130(15) fm. This differs by 4.5 standard deviations from the extrapolated value used to calculate the isospin-symmetry breaking corrections in the superallowed ß decay of ^{26m}Al. Its corrected Ft value, important for the estimation of V_{ud} in the Cabibbo-Kobayashi-Maskawa matrix, is thus shifted by 1 standard deviation to 3071.4(1.0) s.

4.
Phys Rev Lett ; 128(15): 152501, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35499902

RESUMO

The impact of nuclear deformation can been seen in the systematics of nuclear charge radii, with radii generally expanding with increasing deformation. In this Letter, we present a detailed analysis of the precise relationship between nuclear quadrupole deformation and the nuclear size. Our approach combines the first measurements of the changes in the mean-square charge radii of well-deformed palladium isotopes between A=98 and A=118 with nuclear density functional calculations using Fayans functionals, specifically Fy(std) and Fy(Δr,HFB), and the UNEDF2 functional. The changes in mean-square charge radii are extracted from collinear laser spectroscopy measurements on the 4d^{9}5s ^{3}D_{3}→4d^{9}5p ^{3}P_{2} atomic transition. The analysis of the Fayans functional calculations reveals a clear link between a good reproduction of the charge radii for the neutron-rich Pd isotopes and the overestimated odd-even staggering: Both aspects can be attributed to the strength of the pairing correlations in the particular functional which we employ.

5.
Phys Rev Lett ; 128(15): 152701, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35499908

RESUMO

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and ß-delayed neutron emission probability, P_{1 n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.

6.
Zhonghua Yi Xue Za Zhi ; 102(24): 1839-1845, 2022 Jun 28.
Artigo em Zh | MEDLINE | ID: mdl-35725363

RESUMO

Objective: To discuss the clinical value of preserving subvalvular structure in mitral and aortic valve replacement surgery and its effect on left ventricular contractility. Methods: A total of 97 patients who underwent mitral valve replacement surgery in the Adult Cardiac Surgery of Heart Center of Henan Provincial People's Hospital, Central China Fuwai Hospital from June 2016 to December 2018 were selected as the research subjects, of whom 45 cases were preserved subvalvular structure and 52 cases were in the total resection group (intraoperative total resection of the mitral valve and subvalvular chordae tendineae). General cardiac function indexes and left ventricular function quantitative indexes were compared before and in 3 months and 6 months after the operation of the two groups; The changes of the overall longitudinal strain of the long axis of the apex and the overall circumferential strain of the short axis of the left ventricle determined by the two-dimensional speckle tracking technology were compared before and after the operation. Results: The ages of the patients in the preservation group and the total resection group were (41.8±11.3) and (43.3±10.6) years old, respectively, and the male proportions were 58.0% (26 cases) and 44.0% (23 cases), respectively, with no significant difference (all P>0.05). The aortic occlusion time and cardiopulmonary bypass time of the patients in the preservation group were (57.8±4.5) and (78.6±6.7) min, respectively, which were longer than those in the total resection group [(48.1±4.4) and (48.1±4.4) min, respectively] (all P<0.05). The left atrial pressure of the patients in the preservation group at shutdown was (8.4±1.8) mmHg (1 mmHg=0.133 kPa), which was lower than that of the total resection group (11.3±2.5) mmHg (P<0.001). There were interaction effects between groups and time in regards to the left ventricular end-diastolic diameter ( LVEDD ), left ventricular ejection fraction ( LVEF ) and Tei index, as well as the strain rate of mitral annulus and left ventricular wall of interventricular septum of the preservation group and the total resection group (all P<0.05). LVEDD and LVEF of patients in the preservation group at 3rd month after operation were (44.7±4.0) mm and (45.5±4.2) mm, and at 6th months were (56.5±4.9)% and (58.8±5.0)%, respectively, all larger than (42.7±3.6) mm and (42.7±3.6) mm, (54.5±4.6)% and (56.3±4.8)% of the total resection group. The measured value of LVESD in the preservation group at 3rd month after surgery was (32.6±3.2) mm, which was greater than that in the total resection group (31.2±3.4) mm (P<0.05). The Tei index of patients in the preservation group at 3rd and 6th months after surgery were 1.0±0.2 and 0.8±0.2, respectively, which were lower than those in the total resection group 1.2±0.3 and 0.9±0.2 (all P<0.05). Conclusion: Preserving the subvalvular structure during mitral valve replacement surgery can better improve the patient's left ventricular function and left ventricular systolic capacity.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral , Adulto , Valva Aórtica/cirurgia , Cordas Tendinosas/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Ventrículos do Coração , Humanos , Masculino , Insuficiência da Valva Mitral/cirurgia , Volume Sistólico , Função Ventricular Esquerda
7.
Phys Rev Lett ; 127(27): 272301, 2021 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-35061421

RESUMO

The ground state to ground state electron-capture Q value of ^{159}Dy (3/2^{-}) has been measured directly using the double Penning trap mass spectrometer JYFLTRAP. A value of 364.73(19) keV was obtained from a measurement of the cyclotron frequency ratio of the decay parent ^{159}Dy and the decay daughter ^{159}Tb ions using the novel phase-imaging ion-cyclotron resonance technique. The Q values for allowed Gamow-Teller transition to 5/2^{-} and the third-forbidden unique transition to 11/2^{+} state with excitation energies of 363.5449(14) keV and 362.050(40) keV in ^{159}Tb were determined to be 1.18(19) keV and 2.68(19) keV, respectively. The high-precision Q value of transition 3/2^{-}→5/2^{-} from this work, revealing itself as the lowest electron-capture Q value, is used to unambiguously characterize all the possible lines that are present in its electron-capture spectrum. We performed atomic many-body calculations for both transitions to determine electron-capture probabilities from various atomic orbitals and found an order of magnitude enhancement in the event rates near the end point of energy spectrum in the transition to the 5/2^{-} nuclear excited state, which can become very interesting once the experimental challenges of identifying decays into excited states are overcome. The transition to the 11/2^{+} state is strongly suppressed and found unsuitable for measuring the neutrino mass. These results show that the electron-capture in the ^{159}Dy atom, going to the 5/2^{-} state of the ^{159}Tb nucleus, is a new candidate that may open the way to determine the electron-neutrino mass in the sub-eV region by studying electron-capture. Further experimental feasibility studies, including coincidence measurements with realistic detectors, will be of great interest.

8.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(4): 340-344, 2021 Apr 24.
Artigo em Zh | MEDLINE | ID: mdl-33874683

RESUMO

Objective: To investigate the safety and efficacy of ultrafiltration on diuretic sensitivity in heart failure patients with reduced ejection fraction and diuretic resistance. Methods: This was a single-center randomized controlled trial. A total of 148 heart failure patients with reduced ejection fraction admitted to the Hospital of Traditional Chinese Medicine of Xinjiang Uygur Autonomous Region from June 2010 to June 2020 were enrolled in this study, and these patients were randomly divided (ratio 1:1) into the ultrafiltration group (n=74) and the control group (n=74). All patients were treated with diuretics, cardiotonic, vasodilator and other comprehensive drugs according to relevant guidelines. After grouping, the patients in the control group were treated with standard treatment plan, while patients in the ultrafiltration group were treated with ultrafiltration on top of standard therapy. Diuretic drugs were discontinued during ultrafiltration, and intravenously furosemide (40 mg) was given immediately and 24 hours after the end of ultrafiltration. Clinical data including gender, age, complicated diseases, New York Heart Association (NYHA) function classification, etc. were collected. Effectiveness indicators include urine volume (the first 12-hour and 24-hour urine volume and the second 24-hour urine volume after using diuretic), body weight and dyspnea severity score. Safety indicators include systolic blood pressure, serum creatinine, serum Na+ concentration, blood K+ concentration and the number of deaths before and after intervention. Results: Two patients in the control group died due to worsening heart failure after randomization and were excluded in this study, 146 patients were finally analyzed (72 patients in the control group and 74 patients in the ultrafiltration group). There were 93 males, and the age was (68.3±11.2) years. There was no significant difference between patients in the ultrafiltration group and the control group in gender, age, body weight, course of disease, dyspnea severity score, NYHA function classification Ⅲ/Ⅳ, the proportion of patients with severe edema of both lower limbs, the proportion of patients with complicated diseases, and basic medication (all P>0.05). After using diuretics, the urine volume of the first 12-hour and 24-hour and the second 24-hour were significantly higher in the ultrafiltration group than in the control group (all P<0.05). Body weight decreased significantly after ultrafiltration treatment as compared with that before intervention in the ultrafiltration group (P<0.05). Compared with the control group, the dyspnea severity score was significantly improved in the ultrafiltration group (P<0.05). There was no significant difference in systolic blood pressure, serum creatinine, serum Na+ concentration, blood K+ concentration of patients between ultrafiltration group and control group before and after intervention (all P>0.05). During the clinical diagnosis and treatment, 2 male patients in the control group died, and the cause of death was aggravation of basic diseases complicated with acute heart failure and cardiogenic shock. There was no death in the ultrafiltration group, and there were no obvious clinical adverse events during and after ultrafiltration. Conclusion: Ultrafiltration therapy is safe and can improve diuretic sensitivity in heart failure patients with reduced ejection fraction and diuretic resistance.


Assuntos
Diuréticos , Insuficiência Cardíaca , Idoso , Diuréticos/uso terapêutico , Furosemida/uso terapêutico , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Volume Sistólico , Ultrafiltração
9.
Zhonghua Xin Xue Guan Bing Za Zhi ; 49(2): 136-142, 2021 Feb 24.
Artigo em Zh | MEDLINE | ID: mdl-33611899

RESUMO

Objective: To explore the long-term effect of intravascular ultrasound (IVUS) guidance on patients with chronic kidney disease (CKD) undergoing drug-eluting stent (DES) implantation. Methods: Data used in this study derived from ULTIMATE trial, which was a prospective, multicenter, randomized study. From August 2014 to May 2017, 1 448 patients with coronary heart disease undergoing DES implantation were selected from 8 domestic centers and randomly divided into two groups in the ratio of 1∶1 (IVUS or coronary angiography guided stent implantation). A total of 1 443 patients with the baseline serum creatine available were enrolled. The patients were divided into CKD group and non CKD group. CKD was defined as the estimated glomerular filtration rate (eGFR) derived from Cockcroft Gault (CG) formula< 60 ml·min-1·1.73 m-2 for at least 3 months. Primary endpoint of this study was target vessel failure (TVF) at 3 years, including cardiac death, target vessel myocardial infarction, and clinically-driven target vessel revascularization. Kaplan Meier method was used for survival analysis, and log rank test was used to compare the occurrence of end-point events in each group. Cox proportional hazards model was used to calculate HR and 95%CI, and interaction was tested. Multivariate Cox regression was used to analyze the independent influencing factors of TVF. Results: A total of 1 443 patients with coronary heart disease were enrolled in this study, including 349 (24.2%) patients in CKD group and 1 094 patients in non CKD group. In CKD group, IVUS was used to guide stent implantation in 180 cases and angiography was used in 169 cases; in non CKD group, IVUS was used to guide stent implantation in 543 cases and angiography was used in 551 cases. Three-year clinical follow-up was available in 1 418 patients (98.3%). The incidence of TVF in CKD group was 12.0% (42/349), which was higher than that in non CKD group (7.4% (81/1 094) (P = 0.01). The difference was mainly due to the higher cardiac mortality in CKD group (4.6% (16/349) vs. 1.5% (16/1094), P<0.001). In CKD group, the incidence of TVF in patients who underwent IVUS guided stent implantation was lower than that in angiography guided stent implantation (8.3% (15/180) vs. 16.0% (27/169), P = 0.03). There was no significant difference in the incidence of TVF between IVUS guided stent implantation and angiography guided stent implantation in non CKD group (5.9% (32/543) vs. 8.9% (49/551), P = 0.06), and there was no interaction (P = 0.47). Multivariate Cox regression analysis showed that IVUS guidance (HR = 0.56, 95%CI 0.39-0.81, P = 0.002), CKD (HR = 1.83, 95%CI 1.17-2.87, P = 0.010) and stent length (every 10 mm increase) (HR = 1.11, 95%CI 1.04-1.19, P = 0.002) were independent risk factors for TVF within 3 years after DES implantation. Conclusions: CKD patients undergoing DES implantation are associated with a higher risk of 3-year TVF. More importantly, the risk of TVF could be significantly decreased through IVUS guidance in comparison with angiography guidance in patients with CKD.


Assuntos
Doença da Artéria Coronariana , Stents Farmacológicos , Intervenção Coronária Percutânea , Insuficiência Renal Crônica , Angiografia Coronária , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Humanos , Estudos Prospectivos , Resultado do Tratamento , Ultrassonografia de Intervenção
10.
Eur Cell Mater ; 38: 79-93, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478555

RESUMO

Biological effects of pulsed electrical stimulation (PES) on cells and tissues have been intensively studied with the aim of advancing their biomedical applications. These effects vary significantly depending on PES parameters, cell and tissue types, which can be attributed to the diverse variety of signaling pathways, ion channels, and epigenetic mechanisms involved. The development of new technology platforms, such as nanosecond pulsed electric fields (nsPEFs) with finely tuned parameters, have added further complexity. The present review systematically examines current research progress in various aspects of PES, from physical models to biological effects on cells and tissues, including voltage-sensing domains of voltage-gated channels, pore formation, intracellular components/organelles, and signaling pathways. Emphasis is placed on the complexity of PES parameters and inconsistency of induced biological effects, with the aim of exploring the underlying physical and cellular mechanisms of the physiological effects of electrical stimulation on cells. With chondrogenic differentiation of stem cells and cartilage regeneration as examples, the underlying mechanisms involved were reviewed and analyzed, hoping to move forward towards potential biomedical applications. Hopefully, the present review will inspire more interest in the wider clinical applications of PES and lay the basis for further comprehensive studies in this field.


Assuntos
Cartilagem/fisiologia , Condrócitos/citologia , Regeneração , Animais , Cartilagem/citologia , Condrócitos/metabolismo , Condrogênese , Estimulação Elétrica , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo
11.
Epidemiol Infect ; 147: e181, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-31063103

RESUMO

Co-receptor tropism has been identified to correlate with HIV-1 transmission and the disease progression in patients. A molecular epidemiology investigation of co-receptor tropism is important for clinical practice and effective control of HIV-1. In this study, we investigated the co-receptor tropism on HIV-1 variants of 85 antiretroviral-naive patients with Geno2pheno algorithm at a false-positive rate of 10%. Our data showed that a majority of the subjects harboured the CCR5-tropic virus (81.2%, 69/85). No significant differences in gender, age, baseline CD4+ T-cell counts and transmission routes were observed between subjects infected with CXCR4-tropic or CCR5-tropic virus. The co-receptor tropism appeared to be associated with the virus genotype; a significantly more CXCR4-use was predicted in CRF01_AE infections whereas all CRF07_BC and CRF08_BC were predicted to use CCR5 co-receptor. Sequences analysis of V3 revealed a higher median net charge in the CXCR4 viruses over CCR5 viruses (4.0 vs. 3.0, P < 0.05). The predicted N-linked glycosylation site between amino acids 6 and 8 in the V3 region was conserved in CCR5 viruses, but not in CXCR4 viruses. Besides, variable crown motifs were observed in both CCR5 and CXCR4 viruses, of which the most prevalent motif GPGQ existed in both viral tropism and almost all genotypes identified in this study except subtype B. These findings may offer important implications for clinical practice and enhance our understanding of HIV-1 biology.


Assuntos
Antirretrovirais/farmacologia , HIV-1/genética , Tropismo Viral/genética , Adulto , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores CCR5/fisiologia , Adulto Jovem
12.
Zhonghua Yi Xue Za Zhi ; 99(14): 1081-1085, 2019 Apr 09.
Artigo em Zh | MEDLINE | ID: mdl-30982256

RESUMO

Objective: To study the effect of death decoy receptor 3 on the prognosis of breast cancer and the invasive function of breast cancer cells in vitro. Methods: Expression of DcR3 were assessed qualitatively by Q-PCR to analyze the correlation in 115 mammary tissue samples with a 10-year median follow-up. The expression of DcR3 was examined in MCF7 and MDA-MB-231 cell lines using immunocytochemical staining and RT-PCR. DcR3 knock-down cell sub-lines were constructed. The effects of reduced DcR3 expression were observed by establishing invasion and migration models. Results: Patients were divided into the good prognosis group (n=81) and the poor prognosis group (n=26). The expression of DcR3 in the poor prognosis group (133 350+49 646 copies/50 ng RNA)was significantly higher than that in the good prognosis group (5 393+1 428 copies/50 ng RNA, P=0.020). DcR3 transcripts were found to be increased significantly in grade 2 cancers compared to well differentiated grade 1(82 844±34 068 copies/50 ng RNA, n=39,) vs (5 371±3 500 copies/50 ng RNA, n=20, P=0.029).The DcR3 gene of MCF7 cell line and MDA-MB-231 cell line were successfully knocked out and verified that DcR3 knockout. And the invasion and migration of MCF7 cells were inhibited (P=0.009, P=0.001). However, no significant difference was found in these two aspects of the MDA-MB-231 cell line (P=0.475, P=0.102). Conclusion: DcR3 promotes the capacity of invasion of breast cancer cells and plays an important role in the metastasis of breast cancer. DcR3 detection is helpful to the judgment about prognosis of breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Prognóstico , Membro 6b de Receptores do Fator de Necrose Tumoral
13.
Int Endod J ; 49(7): 646-54, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26102215

RESUMO

The aim of this review was to evaluate whether CBCT is reliable for the detection of root fractures in teeth without root fillings, and whether the voxel size has an impact on diagnostic accuracy. The studies published in PubMed, Web of Science, ScienceDirect, Cochrane Library, Embase, Scopus, CNKI and Wanfang up to May 2014 were the data source. Studies on nonroot filled teeth with the i-CAT (n = 8) and 3D Accuitomo CBCT (n = 5) units were eventually selected. In the studies on i-CAT, the pooled sensitivity was 0.83 and the pooled specificity was 0.91; in the 3D Accuitomo studies, the pooled sensitivity was 0.95 and pooled specificity was 0.96. The i-CAT group comprised 5 voxel size subgroups and the 3D Accuitomo group contained 2 subgroups. For the i-CAT group, there was a significant difference amongst the five subgroups (0.125, 0.2, 0.25, 0.3 and 0.4 mm; P = 0.000). Pairwise comparison revealed that 0.125 mm voxel subgroup was significantly different from those of 0.2, 0.25 and 0.3 mm voxel subgroups, but not from the 0.4 mm voxel subgroup. There were no significant differences amongst any other two subgroups (by α' = 0.005). No significant difference was found between 0.08 mm and 0.125 mm voxel subgroups (P = 0.320) for the 3D Accuitomo group. The present review confirms the detection accuracy of root fractures in CBCT images, but does not support the concept that voxel size may play a role in improving the detection accuracy of root fractures in nonroot filled teeth.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Fraturas dos Dentes/diagnóstico por imagem , Raiz Dentária/lesões , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fraturas dos Dentes/diagnóstico , Raiz Dentária/diagnóstico por imagem
14.
Genet Mol Res ; 15(4)2016 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-27808384

RESUMO

In this study, a methylation-sensitive amplification polymorphism analysis system was used to analyze DNA methylation level in three cotton accessions. Two disease-sensitive near-isogenic lines, PD94042 and IL41, and one disease-resistant Gossypium mustelinum accession were exposed to Verticillium wilt, to investigate molecular disease resistance mechanisms in cotton. We observed multiple different DNA methylation types across the three accessions following Verticillium wilt exposure. These included hypomethylation, hypermethylation, and other patterns. In general, the global DNA methylation level was significantly increased in the disease-resistant accession G. mustelinum following disease exposure. In contrast, there was no significant difference in the disease-sensitive accession PD94042, and a significant decrease was observed in IL41. Our results suggest that disease-resistant cotton might employ a mechanism to increase methylation level in response to disease stress. The differing methylation patterns, together with the increase in global DNA methylation level, might play important roles in tolerance to Verticillium wilt in cotton. Through cloning and analysis of differently methylated DNA sequences, we were also able to identify several genes that may contribute to disease resistance in cotton. Our results revealed the effect of DNA methylation on cotton disease resistance, and also identified genes that played important roles, which may shed light on the future cotton disease-resistant molecular breeding.


Assuntos
Metilação de DNA , Gossypium/genética , Doenças das Plantas/genética , Resistência à Doença , Genes de Plantas , Melhoramento Vegetal , Polimorfismo Genético , Verticillium/genética , Verticillium/metabolismo
15.
Persoonia ; 37: 173-198, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-28232764

RESUMO

The sequestrate (truffle-like) basidiomycete genera Rossbeevera, Chamonixia, and Octaviania are closely related to the epigeous mushroom genera Leccinum and Leccinellum. In order to elucidate the properties and placement of several undescribed sequestrate taxa in the group and to reveal the evolutionary history of Rossbeevera and its allies, we conducted phylogenetic analyses based on three nuclear (ITS, nLSU, EF-1α) and two mitochondrial DNA loci (ATP6 and mtSSU) as well as precise morphological observations. Phylogenetic analyses of three nuclear loci suggest a complex evolutionary history with sequestrate fruiting bodies present in several clades, including a previously unrecognized sister clade to Rossbeevera. Here we propose a new sequestrate genus, Turmalinea, with four new species and one new subspecies as well as two new species of Rossbeevera. The three-locus nuclear phylogeny resolves species-level divergence within the Rossbeevera-Turmalinea lineage, whereas a separate phylogeny based on two mitochondrial genes corresponds to geographic distance within each species-level lineage and suggests incomplete lineage sorting (ILS) and gene introgression within several intraspecific lineages of Rossbeevera. Furthermore, topological incongruence among the three nuclear single-locus phylogenies suggests that ancient speciation within Rossbeevera probably involved considerable ILS. We also found an unusually long, minisatellite-like insertion within the ITS2 in all Rossbeevera and Turmalinea species. A barcode gap analysis demonstrates that the insertion is more informative for discrimination at various taxonomic levels than the rest of the ITS region and could therefore serve as a unique molecular barcode for these genera.

16.
Eur Cell Mater ; 30: 12-27, 2015 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-26214287

RESUMO

As a cell source, multipotent mesenchymal stromal cells or mesenchymal stem cells (MSCs) are promising candidates for chondrogenic differentiation and subsequent cartilage regeneration. From previous literature, it is known that chondrogenic differentiation of MSCs inevitably leads to hypertrophy and subsequent endochondral ossification. In this review, we examine the history of currently established protocols of chondrogenic differentiation and elaborate on the roles of individual components of chondrogenic differentiation medium. We also summarise the effects of physical, chemical and biological factors involved, and propose potential strategies to differentiate MSCs into articular chondrocytes with homogenous mature phenotypes through spatial-temporal incorporation of cell differentiation and chondrogenesis.


Assuntos
Cartilagem Articular/citologia , Diferenciação Celular/fisiologia , Condrócitos/citologia , Condrogênese/fisiologia , Células-Tronco Mesenquimais/citologia , Animais , Técnicas de Cocultura/métodos , Humanos
17.
Genet Mol Res ; 14(3): 8883-91, 2015 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-26345819

RESUMO

The purpose of this study was to investigate the mechanism behind adipose tissue wound healing (ATWH). The preadipocyte cell line 3T3-L1 was cultured and expression of adiponectin receptors (AdipoR1/2) was detected by immunohistochemistry and reverse transcription polymerase chain reaction. The concentration of adiponectin secreted at different cell densities was measured by enzyme-linked immunosorbent assay, while preadipocyte proliferation and migration were determined in vitro by MTT and wound closure assays. AdipoR1/2 were found to be expressed in 3T3-L1 preadipocytes. There were no statistically significant differences in the concentrations of adiponectin secreted by cell solutions of different densities (P > 0.05). In addition, adiponectin was seen to promote the growth and migration of preadipocytes. In conclusion, adiponectin may regulate ATWH by promoting preadipocyte proliferation and migration, and its systemic and/or local application is proposed as a promising therapeutic approach for the treatment of wounds incurred as a result of surgery.


Assuntos
Adiponectina/metabolismo , Tecido Adiposo/metabolismo , Cicatrização/fisiologia , Células 3T3-L1 , Adiponectina/biossíntese , Tecido Adiposo/lesões , Tecido Adiposo/patologia , Animais , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Ensaio de Imunoadsorção Enzimática , Camundongos , Receptores de Adiponectina/biossíntese , Receptores de Adiponectina/metabolismo
18.
J Hosp Infect ; 149: 65-76, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38754784

RESUMO

OBJECTIVE: This study aimed to develop a diagnostic model for predicting early surgical site infection (SSI) based on postoperative inflammatory markers after spinal fusion surgery. METHODS: In this retrospective study, we analysed the trends of inflammatory markers between SSI and non-SSI groups. The data were randomly divided into training cohort and validation cohort (ratio 7:3). The variables for SSI were analysed using stepwise logistic regression to develop the prediction model. To evaluate the model, we analysed its sensitivity, specificity, positive predictive value, negative predictive value, as well as the area under the curve in the validation cohort. Calibration plots and decision curve analysis were employed to assess the calibration and clinical usefulness of the model. FINDINGS: We observed significant changes in inflammatory markers on the seventh day after surgery. The prediction model included four variables on the seventh day after surgery: body temperature, C-reactive protein, erythrocyte sedimentation rate and neutrophil counts. After binary processing of these data, the simplified model achieved an area under the curve of 0.86 (95% confidence interval (CI): 0.81-0.92) in the training cohort and 0.9 (95% CI: 0.82-0.98) in the validation cohort. Calibration plots and decision curve analysis demonstrated that the proposed model was effective for the diagnosis of SSI. CONCLUSION: We developed and validated a prediction model for diagnosing early infection after spinal fusion.


Assuntos
Fusão Vertebral , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/diagnóstico , Fusão Vertebral/efeitos adversos , Estudos Retrospectivos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Modelos Logísticos , Proteína C-Reativa/análise , Sensibilidade e Especificidade , Biomarcadores/sangue , Valor Preditivo dos Testes
19.
Zhonghua Er Ke Za Zhi ; 62(4): 345-350, 2024 Mar 25.
Artigo em Zh | MEDLINE | ID: mdl-38527505

RESUMO

Objective: To investigate the clinical phenotype and genetic characteristics of patients with Fabry disease caused by a GLA variant, IVS4+919G>A. Methods: It was a prospective study. Fabry disease screening was conducted among high-risk population in Ninghai from October 2021 to August 2023. Those children with decreased α-galactosidase enzyme activity<2.40 µmol/(L·h) or elavated Lyso-GL-3 level>1.10 µg/L in dried blood spot (DBS) method underwent GLA genetic testing for diagnosis confirmation. Meanwhile, family screening was carried out. A proband and his family members diagnosed with Fabry disease were research subjects. The clinical and genetic characteristics of patients with Fabry disease caused by the GLA variant (IVS4+919G>A) were analyzed. Results: The female proband aged 9.8 years with pain in both lower limbs as the initial symptom was found to have a heterozygous GLA variant IVS4+919G>A among 102 patients. In family screening, there were 4 family members (proband's father, elder sister, elder male cousin and elder female cousin) with Fabry disease and a family member (proband's fifth aunt) with a GLA variant. Among these 4 diagnosed family members, the elder male cousin of the proband, a boy aged 13.2 years had a heterozygous GLA variant, IVS4+919G>A with intermittent pain in both lower limbs as the initial symptom. The proband's father had knee joint pain. The proband's elder sister had decreased vision and his elder female cousin had no obvious symptoms. The proband's fifth aunt with a GLA variant had decreased vision. Conclusions: High-risk screening in children and family screening are helpful for early diagnosis and treatment of Fabry disease. Neuropathic pain may be a early symptom in children with Fabry disease caused by the GLA variant, IVS4+919G>A.


Assuntos
Doença de Fabry , Criança , Humanos , Masculino , Feminino , Idoso , Doença de Fabry/diagnóstico , Doença de Fabry/genética , Doença de Fabry/epidemiologia , alfa-Galactosidase/genética , Linhagem , Estudos Prospectivos , Mutação , Fenótipo , Heterozigoto , Dor
20.
Mol Ecol ; 22(6): 1717-32, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23205556

RESUMO

Fungal mitospores may function as dispersal units and/ or spermatia and thus play a role in distribution and/or mating of species that produce them. Mitospore production in ectomycorrhizal (EcM) Pezizales is rarely reported, but here we document mitospore production by a high diversity of EcM Pezizales on three continents, in both hemispheres. We sequenced the internal transcribed spacer (ITS) and partial large subunit (LSU) nuclear rDNA from 292 spore mats (visible mitospore clumps) collected in Argentina, Chile, China, Mexico and the USA between 2009 and 2012. We collated spore mat ITS sequences with 105 fruit body and 47 EcM root sequences to generate operational taxonomic units (OTUs). Phylogenetic inferences were made through analyses of both molecular data sets. A total of 48 OTUs from spore mats represented six independent EcM Pezizales lineages and included truffles and cup fungi. Three clades of seven OTUs have no known meiospore stage. Mitospores failed to germinate on sterile media, or form ectomycorrhizas on Quercus, Pinus and Populus seedlings, consistent with a hypothesized role of spermatia. The broad geographic range, high frequency and phylogenetic diversity of spore mats produced by EcM Pezizales suggests that a mitospore stage is important for many species in this group in terms of mating, reproduction and/or dispersal.


Assuntos
Ascomicetos/classificação , Micorrizas/classificação , Filogenia , Ascomicetos/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Funções Verossimilhança , Dados de Sequência Molecular , Micorrizas/genética , Pinus/microbiologia , Raízes de Plantas/microbiologia , Populus/microbiologia , Quercus/microbiologia , Análise de Sequência de DNA , Esporos Fúngicos/classificação , Esporos Fúngicos/genética
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