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1.
Phys Rev Lett ; 132(15): 155102, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38683000

RESUMEN

We present the first experimental study of plasmoid formation in a magnetic reconnection layer undergoing rapid radiative cooling, a regime relevant to extreme astrophysical plasmas. Two exploding aluminum wire arrays, driven by the Z machine, generate a reconnection layer (S_{L}≈120) in which the cooling rate far exceeds the hydrodynamic transit rate (τ_{hydro}/τ_{cool}>100). The reconnection layer generates a transient burst of >1 keV x-ray emission, consistent with the formation and subsequent rapid cooling of the layer. Time-gated x-ray images show fast-moving (up to 50 km s^{-1}) hotspots in the layer, consistent with the presence of plasmoids in 3D resistive magnetohydrodynamic simulations. X-ray spectroscopy shows that these hotspots generate the majority of Al K-shell emission (around 1.6 keV) prior to the onset of cooling, and exhibit temperatures (170 eV) much greater than that of the plasma inflows and the rest of the reconnection layer, thus providing insight into the generation of high-energy radiation in radiatively cooled reconnection events.

2.
Am J Med Genet A ; 194(7): e63576, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38407483

RESUMEN

Genetic testing for germline RET pathogenic variants, which cause the Multiple Endocrine Neoplasia Type 2 (MEN2) syndrome, has become crucial in managing patients with medullary thyroid carcinoma (MTC). Classically, RET heterozygous missense pathogenic variants are transmitted in a Mendelian autosomal dominant pattern, of which germline/gonadal mosaicism has never been reported. We report the novel occurrence of a MEN2A patient's family in which the siblings inherited three different RET 634 genotypes: wild type (p.Cys634), p.Cys634Gly or p.Cys634Arg heterozygous pathogenic variants. We hypothesized that germline/gonadal mosaicism, derived from an inherited + early somatic mutation in the mother or a double de novo mutation during maternal embryogenesis, led to this rare event in the RET gene. Exome analysis of the proband's deceased mother's paraffin-embedded thyroid tissue confirmed the three nucleotides in the same 634 codon position. For the first time, we describe germline/gonadal mosaicism in RET, generating a second pathogenic amino acid change in the same codon causing MEN2A. Our finding shows that RET parental mosaicism, confirmed by somatic exome sequencing, might explain discrepant genotype cases in siblings with inherited cancers.


Asunto(s)
Mutación de Línea Germinal , Mosaicismo , Neoplasia Endocrina Múltiple Tipo 2a , Linaje , Proteínas Proto-Oncogénicas c-ret , Humanos , Neoplasia Endocrina Múltiple Tipo 2a/genética , Neoplasia Endocrina Múltiple Tipo 2a/patología , Proteínas Proto-Oncogénicas c-ret/genética , Mutación de Línea Germinal/genética , Femenino , Masculino , Adulto , Sustitución de Aminoácidos , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Genotipo , Secuenciación del Exoma
3.
Philos Trans A Math Phys Eng Sci ; 381(2246): 20220119, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36907209

RESUMEN

A concise review is given of astrophysically motivated experimental and theoretical research on Taylor-Couette flow. The flows of interest rotate differentially with the inner cylinder faster than the outer, but are linearly stable against Rayleigh's inviscid centrifugal instability. At shear Reynolds numbers as large as [Formula: see text], hydrodynamic flows of this type (quasi-Keplerian) appear to be nonlinearly stable: no turbulence is seen that cannot be attributed to interaction with the axial boundaries, rather than the radial shear itself. Direct numerical simulations agree, although they cannot yet reach such high Reynolds numbers. This result indicates that accretion-disc turbulence is not purely hydrodynamic in origin, at least insofar as it is driven by radial shear. Theory, however, predicts linear magnetohydrodynamic (MHD) instabilities in astrophysical discs: in particular, the standard magnetorotational instability (SMRI). MHD Taylor-Couette experiments aimed at SMRI are challenged by the low magnetic Prandtl numbers of liquid metals. High fluid Reynolds numbers and careful control of the axial boundaries are required. The quest for laboratory SMRI has been rewarded with the discovery of some interesting inductionless cousins of SMRI, and with the recently reported success in demonstrating SMRI itself using conducting axial boundaries. Some outstanding questions and near-future prospects are discussed, especially in connection with astrophysics. This article is part of the theme issue 'Taylor-Couette and related flows on the centennial of Taylor's seminal Philosophical Transactions paper (Part 2)'.

4.
J Endocrinol Invest ; 46(4): 687-698, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36301436

RESUMEN

PURPOSE: The role of computed tomography (CT) in the diagnosis of primary aldosteronism (PA) warrants attention, since the success application of adrenal venous sampling (AVS) remains limited. We aimed to investigate the value of CT-based volumetric indicators, including left-versus-right-adrenal-volume ratio (L/Rv) and left-subtract-right-adrenal-volume difference (L - Rv), in the diagnosis of unilateral primary aldosteronism (UPA). METHODS: A retrospective case-control study included 153 patients with PA and 1272 controls. AVS was used to classify patients into bilateral disease, left-sided disease, and right-sided disease groups. RESULTS: Adrenal gland volume on both sides of PA patients was significantly larger than controls. The optimal cutoff values of L/Rv and L - Rv were 1.417 [area under the curve (AUC) 0.864] and 1.185 (AUC 0.827), respectively, for the diagnosis of left-sided PA, and 1.030 (AUC 0.767) and 0.220 (AUC 0.769), respectively, for the diagnosis of right-sided PA. The mean AUC for subsequent cross-validation ranged from 0.77 ± 0.03 to 0.86 ± 0.02. Based on the optimal cutoff values, the combination of L/Rv and L - Rv detected 69.6% of patients with left-sided PA and 74.3% of patients with right-sided PA, with a specificity of 93.5% and 89.0%, respectively. For a better clinical application, we reported the sub-optimal cutoffs corresponding to a specificity of 95%. A L/Rv higher than 1.431 and a L - Rv higher than 3.185 as sub-optimal cutoff values was detected in 26.1% of patients with left-sided PA (specificity: 97.2%). A L/Rv smaller than 0.892 and a L - Rv smaller than -0.640 could detect 48.6% of patients with right-sided PA (specificity: 97.5%). CONCLUSIONS: CT-based L/Rv and L - Rv performed well in predicting UPA. The combination of L/Rv and L - Rv may serve as a potential indicator for guiding surgical decision making in centers without AVS programs.


Asunto(s)
Hiperaldosteronismo , Humanos , Hiperaldosteronismo/diagnóstico , Hiperaldosteronismo/cirugía , Aldosterona , Estudios Retrospectivos , Estudios de Casos y Controles , Glándulas Suprarrenales/diagnóstico por imagen , Adrenalectomía
5.
Int J Mol Sci ; 24(3)2023 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-36769186

RESUMEN

H2 permeation in peroxide-crosslinked EPDM blended with carbon black (CB) and silica fillers was studied at pressures ranging from 1.2 MPa to 90 MPa via the volumetric analysis technique. H2 uptake in the CB-filled EPDM revealed dual-sorption behaviors via Henry's law and the Langmuir model, which were attributed to H2 absorption by the polymer chains and H2 adsorption at the filler interfaces, respectively. Additionally, single-sorption mechanisms were observed for neat EPDM and silica-blended EPDM according to Henry's law, indicating H2 absorption by the polymer chain. The linear decreases in the diffusivity with filler content for the silica-blended EPDMs were attributed to increases in the diffusion paths caused by the filler. Exponential decreases in the diffusivity with increasing filler content and in the permeation with the physical/mechanical properties for CB-filled EPDMs were caused by decreases in the fractional free volume due to increased densities for the EPDM composites. Moreover, good filler-dependent correlations between permeability and density, hardness, and tensile strength were demonstrated for EPDMs used as sealing materials for O-rings. From the resulting equation, we predicted the permeation value without further measurements. Thus, we can select EPDM candidates satisfying the permeation guidelines used in hydrogen infrastructure for the future hydrogen economy.


Asunto(s)
Polímeros , Hollín , Polímeros/química , Dióxido de Silicio , Hidrógeno , Etilenos
6.
Zhonghua Nei Ke Za Zhi ; 62(6): 693-699, 2023 Jun 01.
Artículo en Zh | MEDLINE | ID: mdl-37263953

RESUMEN

Objective: To establish and validate a nomogram-based predictive model for idiopathic hyperaldosteronism (IHA). Methods: This cross-sectional study was conducted with the collected clinical and biochemical data of patients with primary aldosteronism (PA) including 249 patients with unilateral primary aldosteronism (UPA) and 107 patients with IHA, who were treated at the Department of Endocrinology of the First Affiliated Hospital of Chongqing Medical University from November 2013 to November 2022. Plasma aldosterone concentration (PAC) and plasma renin concentration (PRC) were measured by chemiluminescence. Stepwise regression analysis was applied to select the key predictors of IHA, and a nomogram-based scoring model was developed. The model was validated in another external independent cohort of patients with PA including 62 patients with UPA and 43 patients with IHA, who were diagnosed at the Department of Endocrinology, First Affiliated Hospital of Zhengzhou University. An independent-sample t test, Mann-Whitney U test, and χ2 test were used for statistical analysis. Results: In the training cohort, in comparison with the UPA group, the IHA group showed a higher serum potassium level [M(Q1, Q3), 3.4 (3.1, 3.8) mmol/L vs. 2.7 (2.1, 3.1) mmol/L] and higher PRC [4.0 (2.1, 8.2) mU/L vs. 1.5 (0.6, 3.4) mU/L] and a lower PAC post-saline infusion test (SIT) [305 (222, 416) pmol/L vs. 720 (443, 1 136) pmol/L] and a lower rate of unilateral adrenal nodules [33.6% (36/107) vs. 81.1% (202/249)]; the intergroup differences in these measurements were statistically significant (all P<0.001). Serum potassium level, PRC, PAC post-SIT, and the rate of unilateral adrenal nodules showed similar performance in the IHA group in the validation cohort. After stepwise regression analysis for all significant variables in the training cohort, a scoring model based on a nomogram was constructed, and the predictive parameters included the rate of unilateral adrenal nodules, serum potassium concentration, PAC post-SIT, and PRC in the standing position. When the total score was ≥14, the model showed a sensitivity of 0.65 and specificity of 0.90 in the training cohort and a sensitivity of 0.56 and specificity of 1.00 in the validation cohort. Conclusion: The nomogram was used to successfully develop a model for prediction of IHA that could facilitate selection of patients with IHA who required medication directly.


Asunto(s)
Hiperaldosteronismo , Hipertensión , Humanos , Hiperaldosteronismo/diagnóstico , Nomogramas , Estudios Transversales , Aldosterona , Solución Salina , Renina , Potasio
7.
Zhonghua Xin Xue Guan Bing Za Zhi ; 51(12): 1240-1246, 2023 Dec 24.
Artículo en Zh | MEDLINE | ID: mdl-38123206

RESUMEN

Objective: To investigate the prevalence of dyslipidemia and the level of blood lipids among Tajik people in Pamir Plateau, Xinjiang, and explore the related factors of dyslipidemia. Methods: It is a retrospective cross-sectional study. A multi-stage cluster random sampling survey was conducted among 5 635 Tajiks over 18 years old in Tashkorgan Tajik Autonomous County, Xinjiang Province from May to October 2021. Data were collected through questionnaire survey (general information, medical history, and personal history), physical examination (height, weight, waist, and blood pressure) and blood test (total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density cholesterol (HDL-C)) to analyze the dyslipidemia and its risk factors among Tajiks. Results: The age of Tajik participants was (41.9±15.0) years, including 2 726 males (48.4%). The prevalence of borderline high TC, high LDL-C and high TG levels were 17.2%, 14.7% and 8.9%, respectively. The prevalence of high TC, high LDL-C, high TG and low HDL-C were 4.1%, 4.9%, 9.4% and 32.4%, respectively, and the prevalence of dyslipidemia was 37.0%. There is a positive correlation between male,higher education level, higher body mass index (BMI) value,waist circumference, living in town, smoking and dyslipidemia. Conclusions: The low prevalence of high TC, high LDL-C, high TG and high prevalence of low HDL-C was a major characteristic of Tajik people in Pamir Plateau of Xinjiang. The lower rates of overweight and obesity may be one of the reasons for the lower prevalence of dyslipidemia among Tajik.


Asunto(s)
Dislipidemias , Hipercolesterolemia , Hipertrigliceridemia , Adulto , Humanos , Masculino , Persona de Mediana Edad , Colesterol , HDL-Colesterol , LDL-Colesterol , Estudios Transversales , Dislipidemias/epidemiología , Hipercolesterolemia/epidemiología , Hipertrigliceridemia/epidemiología , Prevalencia , Estudios Retrospectivos , Femenino
8.
Artículo en Zh | MEDLINE | ID: mdl-37006147

RESUMEN

Objective: To analyze the serum carbohydrate antigen 125 (CA125) level and its influencing factors in male silicosis patients with pulmonary heart disease. Methods: In October 2021, data of 38 male patients with simple silicosis (silicosis group), 28 cases of silicosis with pulmonary heart disease (pulmonary heart disease group), and 27 healthy controls (control group) in the same age group were collected in inpatient and outpatient of Nanjing Occupational Disease Prevention and Control Hospital from January 2017 to December 2020. The serum CA125 levels of the three groups were compared, and the correlation between disease-related indexes and serum CA125 in silicosis patients with pulmonary heart disease was analyzed, as well as the influencing factors of pulmonary heart disease and serum CA125 levels in silicosis patients. Results: The serum CA125 level[ (19.95±7.52) IU/ml] in pulmonary heart disease group was higher than that in silicosis group[ (12.98±6.35) IU/ml] and control group[ (9.17±5.32) IU/ml] (P<0.05). There was no significant difference in serum CA125 level between the silicosis group and the control group (P>0.05). Serum CA125 levels were positively correlated with blood uric acid and fasting blood glucose in silicosis patients with pulmonary heart disease (r=0.39, 0.46, P<0.05). Serum CA125 level was a risk factor for silicosis patients with pulmonary heart disease (OR=1.13, 95%CI: 1.02-1.24, P<0.05). Dust exposure time, lactate dehydrogenase and smoking history were positively correlated with serum CA125 level in silicosis patients (P<0.05) . Conclusion: The serum CA125 level of male silicosis patients with pulmonary heart disease is significantly increased, and the level of CA125 is correlated with the level of fasting blood glucose and blood uric acid.


Asunto(s)
Enfermedad Cardiopulmonar , Silicosis , Humanos , Masculino , Glucemia , Ácido Úrico , Silicosis/complicaciones , Factores de Riesgo
9.
Zhonghua Nei Ke Za Zhi ; 61(9): 1023-1030, 2022 Sep 01.
Artículo en Zh | MEDLINE | ID: mdl-36008295

RESUMEN

Objective: To characterize the histopathological subtypes and their clinicopathological parameters of gender and onset age by common, rare and sparse primary esophageal malignant tumors (PEMT). Methods: A total of 272 437 patients with PEMT were enrolled in this study, and all of the patients were received radical surgery. The clinicopathological information of the patients was obtained from the database established by the State Key Laboratory of Esophageal Cancer Prevention & Treatment from September 1973 to December 2020, which included the clinical treatment, pathological diagnosis and follow-up information of esophagus and gastric cardia cancers. All patients were diagnosed and classified by the criteria of esophageal tumor histopathological diagnosis and classification (2019) of the World Health Organization (WHO). The esophageal tumors, which were not included in the WHO classification, were analyzed separately according to the postoperative pathological diagnosis. The χ2 test was performed by the SPSS 25.0 software on count data, and the test standard α=0.05. Results: A total of 32 histopathological types were identified in the enrolled PEMT patients, of which 10 subtypes were not included in the WHO classification. According to the frequency, PEMT were divided into common (esophageal squamous cell carcinoma, ESCC, accounting for 97.1%), rare (esophageal adenocarcinoma, EAC, accounting for 2.3%) and sparse (mainly esophageal small cell carcinoma, malignant melanoma, etc., accounting for 0.6%). All the common, rare, and sparse types occurred predominantly in male patients, and the gender difference of rare type was most significant (EAC, male∶ female, 2.67∶1), followed with common type (ESCC, male∶ female, 1.78∶1) and sparse type (male∶ female, 1.71∶1). The common type (ESCC) mainly occurred in the middle thoracic segment (65.2%), while the rare type (EAC) mainly occurred in the lower thoracic segment (56.8%). Among the sparse type, malignant melanoma and malignant fibrous histiocytoma were both predominantly located in the lower thoracic segment (51.7%, 66.7%), and the others were mainly in the middle thoracic segment. Conclusion: ESCC is the most common type among the 32 histopathological types of PEMT, followed by EAC as the rare type, and esophageal small cell carcinoma and malignant melanoma as the major sparse type, and all of which are mainly occur in male patients. The common type of ESCC mainly occur in the middle thoracic segment, while the rare type of EAC mainly in the lower thoracic segment. The mainly sparse type of malignant melanoma and malignant fibrous histiocytoma predominately occur in the lower thoracic segment, and the remaining sparse types mainly occur in the middle thoracic segment.


Asunto(s)
Carcinoma de Células Pequeñas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Histiocitoma Fibroso Maligno , Melanoma , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/patología , Femenino , Humanos , Masculino
10.
Beijing Da Xue Xue Bao Yi Xue Ban ; 54(6): 1172-1177, 2022 Dec 18.
Artículo en Zh | MEDLINE | ID: mdl-36533351

RESUMEN

OBJECTIVE: To analyze the factors related to the need for revision surgery due to nonunion or internal fixation failure after the treatment of distal femoral fracture with lateral locking plate (LLP). METHODS: Retrospective analysis was made of the clinical data of 130 cases with distal femoral fracture treated in our hospital from March 2005 to March 2019. SPSS 17.0 software (univariate analysis and Logistic regression analysis) was used to analyze the general condition [gender, age, body mass index (BMI), comorbidities, smoking history], injury related factors (energy of injury, open or closed injury, AO/OTA classification of fracture, fracture area distribution), operation related factors (operation time, reduction quality, postoperative infection) and construct characteristics of internal fixation. RESULTS: Twelve of 130 patients who were included in the study underwent revisional surgery, with a revision rate 9.2%. Univariate analysis showed that there were significant differences in age, BMI, AO/OTA classification, fracture area distribution, operation time, reduction quality, length of plate/fracture area, length of plate/fracture area above condylar between the two groups (P < 0.05). Logistic regression analysis showed that AO/OTA classification (A3), supracondylar involved fracture, operation time, reduction quality and the length of the plate/fracture area above the condylar were the possible related factors (P < 0.05). Destruction of the medial support ability of the femur in comminuted type A3 fracture, supra-condylar cortex area fracture involvement, increase of the bending stress of the LLP due to poor fracture reduction quality, damage of the blood supply of fracture end due to long-time operation, and stress concentration caused by insufficient length of plate might be risk factors of revisional operation after the treatment of distal femoral fracture with LLP. For the patients who needed revision after LLP treatment, additional use of medial minimally invasive plate fixation and autologous bone transplantation, change to intramedullary nail fixation were commonly used clinical treatment strategies. CONCLUSION: AO/OTA classification (A3), supracondylar involved fracture, long operation time, poor reduction quality and the length of the plate/fracture area above the condylar were the possible predictive factors of the revision in distal femoral fractures treated with lateral locking plate. The appropriate application of the locking plate and operation strategy are the key to reduce the revision rate in distal femoral fractures.


Asunto(s)
Fracturas Femorales Distales , Fracturas del Fémur , Humanos , Fracturas del Fémur/cirugía , Fracturas del Fémur/etiología , Estudios Retrospectivos , Placas Óseas/efectos adversos , Fijación Interna de Fracturas/efectos adversos , Resultado del Tratamiento
11.
Zhonghua Xin Xue Guan Bing Za Zhi ; 50(9): 873-880, 2022 Sep 24.
Artículo en Zh | MEDLINE | ID: mdl-36096704

RESUMEN

Objective: To compare the clinical features and the outcome of in-hospital mortality between patients with myocardial infarction with non-obstructive coronary arteries(MINOCA)and myocardial infarction with obstructive coronary artery disease (MI-CAD). Methods: This is a retrospective study. The clinical data of acute myocardial infarction (AMI) patients admitted to Qilu Hospital of Shandong University from January 2017 to May 2021, who underwent coronary angiography, were collected. Patients were divided into MINOCA group and MI-CAD group according to the degree of coronary stenosis (<50% or ≥50%). Baseline clinical characteristics, electrocardiograph during hospitalization, myocardial bridge, length of stay in hospital, discharge medication and the outcome of in-hospital mortality were collected and compared between the two groups. Univariate and multivariate logistic regression analysis was used to screen the related factors of MINOCA and the factors predicting the nosocomial death outcome of patients with AMI. Results: A total of 3 048 AMI patients were enrolled, age was 62 (54, 69) years, 741 (24.3%) patients were women including 165 patients (5.4%) in the MINOCA group and 2 883 patients (94.6%) in the MI-CAD group. Compared with MI-CAD patients, MINOCA patients were younger, had a higher proportion of females and a higher incidence of NSTEMI, and had a lower history of smoking, diabetes, coronary heart disease and myocardial infarction. Baseline inflammatory markers such as neutrophil count, monocyte count, neutrophil count/lymphocyte count (NLR), and monocyte count/high-density lipoprotein count (MHR) were lower, creatinine, N-terminal pro-brain B-type Natriuretic peptides (NT-proBNP), creatine kinase-MB, hypersensitive troponin I, fibrinogen, baseline blood glucose levels were lower, high-density lipoprotein cholesterol was higher, and the incidence of myocardial bridge, arrhythmia, tachycardia and atrial fibrillation was higher (P<0.05). The application rates of calcium antagonists and non-vitamin K antagonists oral anticoagulants were higher in MINOCA group (P<0.05), and there was no statistical difference in hospitalization days and in-hospital death between the two groups (P>0.05). Multiple logistic regression analysis showed that young age, female, non-smoker, no history of coronary heart disease and low MHR were risk factors of MINOCA (P<0.05). MINCOA was not associated with higher in-hospital death (P>0.05). Patients with AMI and a history of coronary heart disease, chronic renal failure, higher baseline blood glucose, higher NLR, and higher D-dimer were risk factors of in-hospital death (P<0.05). Conclusions: Compared with MI-CAD patients, MINOCA patients are younger, more likely to be female and non-smokers and on history of coronary heart disease, and have lower baseline MHR. MINOCA is often associated with myocardial bridge and atrial fibrillation. The incidence of in-hospital death in MINCOA patients is similar as in MI-CAD patients.


Asunto(s)
Fibrilación Atrial , Enfermedad de la Arteria Coronaria , Infarto del Miocardio , Fibrilación Atrial/complicaciones , Glucemia , Enfermedad de la Arteria Coronaria/complicaciones , Femenino , Mortalidad Hospitalaria , Humanos , Lipoproteínas HDL , MINOCA , Masculino , Infarto del Miocardio/complicaciones , Estudios Retrospectivos
12.
Phys Rev Lett ; 127(5): 055102, 2021 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-34397253

RESUMEN

By examining the entropy production in fully kinetic simulations of collisional plasmas, it is shown that the transition from collisional Sweet-Parker reconnection to collisionless Hall reconnection may be viewed as a thermodynamic phase transition. The phase transition occurs when the reconnection electric field satisfies E=E_{D}sqrt[m_{e}/m_{i}], where m_{e}/m_{i} is the electron-to-ion mass ratio and E_{D} is the Dreicer electric field. This condition applies for all m_{i}/m_{e}, including m_{i}/m_{e}=1, where the Hall regime vanishes and a direct phase transition from the collisional to the kinetic regime occurs. In the limit m_{e}/m_{i}→0, this condition is equivalent to there being a critical electron temperature T_{e}≈m_{i}Ω_{i}^{2}δ^{2}, where Ω_{i} is the ion cyclotron frequency and δ is the current sheet half-thickness. The heat capacity of the current sheet changes discontinuously across the phase transition, and a critical power law is identified in an effective heat capacity. A model for the time-dependent evolution of an isolated current sheet in the collisional regime is derived.

13.
Phys Chem Chem Phys ; 23(39): 22476-22482, 2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34586129

RESUMEN

Biological probes with integrated photoluminescence and magnetism characteristics play a critical role in modern clinical diagnosis and surgical protocols combining fluorescence optical imaging (FOI) with magnetic resonance imaging (MRI) technology. However, traditional magnetic semiconductors can easily generate a spin splitting at the Fermi level and half-metallic electronic occupation, which will sharply reduce the radiation recombination efficiency of photogenerated carriers. To overcome this intrinsic contradiction, we propose a controllable oxidation strategy to introduce some particular PO bonds into black phosphorus nanosheets, in which the p orbital hybridization between P and O atoms not only provides some carrier recombination centers but also leads to a room-temperature spin polarization. As a result, the coexistence of photoluminescence and magnetism is realized in multifunctional black phosphorus probes with excellent biocompatibility. This work provides a new insight into integrating photoluminescence and magnetism together by intriguing atomic orbital hybridization.

14.
Clin Radiol ; 76(5): 393.e1-393.e7, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33568324

RESUMEN

AIM: To evaluate the changes in CCA-IMT and vascular elasticity in healthy subjects in relation to age using radiofrequency data technology, to produce reference values for potential clinical applications. MATERIALS AND METHODS: The following variables were measured in 160 subjects using radiofrequency data techniques: CCA-IMT, carotid distensibility (CD), local pulse-wave velocity (PWVß), and stiffness (ß). The subjects were divided into four age groups (30-39, 40-49, 50-59, and 60-69 years), with 20 men and 20 women in each group. The above parameters were compared among the different age groups. RESULTS: CCA-IMT increased significantly with age (p<0.05). CD decreased significantly in the 40-49-years compared with the 30-39-years age group (p<0.05). PWVß showed a significant increase in the 30-39-, 40-49-, and 50-59-years age groups (p<0.05). ß increased significantly in the 50-59- compared with the 40-49-years age group (p<0.05). Compared with the 50-59-years age group, CD, PWVß, and ß showed no significant changes in the 60-69-years age group (p>0.05), with mean values of 329.39 ± 102.06 µm, 7.22 ± 1.91 m/s, and 10.04 ± 4.91, respectively. CONCLUSION: Ultrasound radiofrequency data technology provides a non-invasive method for quantitatively and accurately assessing increased CCA-IMT and reduced vascular elasticity in healthy subjects in different age groups. The reference values produced in this study will be useful in clinical practice.


Asunto(s)
Arteria Carótida Común/anatomía & histología , Arteria Carótida Común/fisiología , Ultrasonografía/métodos , Adulto , Factores de Edad , Anciano , Elasticidad/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de la Onda del Pulso
15.
Proc Natl Acad Sci U S A ; 115(29): E6741-E6750, 2018 07 17.
Artículo en Inglés | MEDLINE | ID: mdl-29954863

RESUMEN

Each of the 30 human amyloid diseases is associated with the aggregation of a particular precursor protein into amyloid fibrils. In transthyretin amyloidosis (ATTR), mutant or wild-type forms of the serum carrier protein transthyretin (TTR), synthesized and secreted by the liver, convert to amyloid fibrils deposited in the heart and other organs. The current standard of care for hereditary ATTR is liver transplantation, which replaces the mutant TTR gene with the wild-type gene. However, the procedure is often followed by cardiac deposition of wild-type TTR secreted by the new liver. Here we find that amyloid fibrils extracted from autopsied and explanted hearts of ATTR patients robustly seed wild-type TTR into amyloid fibrils in vitro. Cardiac-derived ATTR seeds can accelerate fibril formation of wild-type and monomeric TTR at acidic pH and under physiological conditions, respectively. We show that this seeding is inhibited by peptides designed to complement structures of TTR fibrils. These inhibitors cap fibril growth, suggesting an approach for halting progression of ATTR.


Asunto(s)
Amiloide/química , Miocardio/química , Prealbúmina/química , Amiloide/metabolismo , Neuropatías Amiloides Familiares/metabolismo , Neuropatías Amiloides Familiares/patología , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino , Miocardio/metabolismo , Miocardio/patología , Prealbúmina/metabolismo
16.
Aesthetic Plast Surg ; 45(1): 193-197, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32356151

RESUMEN

BACKGROUND: Facial rejuvenation results, commonly seen in publications or national presentations, are fraught with uncorrected eyelid ptosis. This study was conducted to investigate the frequency of blepharoptosis in the rejuvenation population and to help increase awareness in recognizing this under corrected condition. METHODS: Fifty-nine consecutive patients being evaluated for facial rejuvenation were included in the study. Patients who had previous eyelid or forehead surgery, congenital abnormalities, or post-traumatic deformities were excluded. Standard preoperative photographs were obtained. Each photograph was analyzed to determine blepharoptosis by measuring the distance between the upper eyelid margin and the upper limbus in each eye using Adobe Photoshop. Patient age, gender, and race were reported. Ptosis was defined as more than 1.0 mm overlap between the upper eyelid margin and the upper limbus. RESULTS: Mean age was 63.7. Among 59 patients, 34 patients (57.6%) had blepharoptosis and 25 patients did not. Patients with blepharoptosis were likely to be older and male. CONCLUSION: Blepharoptosis becomes more common as patients age due to involution of eyelid and orbital tissue. It is commonly missed due to patient compensation by recruiting the frontalis muscle to lift the eyelids. It is imperative for the patient and the plastic surgeon to be aware of existing blepharoptosis and discuss expectations and formulate a comprehensive surgical plan. Awareness of the high prevalence of ptosis in the facial rejuvenation population allows plastic surgeons to provide better outcomes and higher patient satisfaction. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Blefaroplastia , Blefaroptosis , Blefaroptosis/diagnóstico , Blefaroptosis/epidemiología , Blefaroptosis/etiología , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Rejuvenecimiento , Estudios Retrospectivos
17.
Zhonghua Nei Ke Za Zhi ; 60(1): 22-28, 2021 Jan 01.
Artículo en Zh | MEDLINE | ID: mdl-33397017

RESUMEN

Objective: To investigate the effect of a 2-year resistance and aerobic training on reducing the risk of cardiovascular disease in patients with prediabetes. Methods: A total of 248 patients with prediabetes were enrolled from Chinese and Western Medicine Hospital Affiliated to Nanjing University of Chinese Medicine from January to April 2014, and Danyang People's Hospital and The First Affiliated Hospital of Guangxi Medical University from May to December 2014.Based on random number table method, the patients were divided into 3 groups: the resistance training group (RT group, 82 cases), the aerobic training group (AT group, 83 cases) and control group (83 cases). Participants in the RT group and the AT group underwent a total of 24 months of exercise training. Changes in indicators (blood glucose,blood lipid, etc.) at baseline and the end of 12 and 24 months among the groups were compared. Results: After intervention, glycosylated hemoglobin (HbA1c), low density lipoprotein cholesterol (LDL-C), blood pressure and homeostasis model 2 insulin resistance index (HOMA2-IR) in the RT and AT groups tended to decrease, and the steady state model 2 ß cell function index (HOMA2-ß) tended to increase. At the end of 24 months, HbA1c [5.80 (5.43, 6.20) %, 5.70 (5.50, 6.00)% vs. 6.20 (5.70, 6.60) %, all P ≤ 0.01], LDL-C [3.07 (2.69, 3.58) mmol/L, 2.97 (2.62, 3.95) mmol/L vs. 3.21(2.54, 3.78) mmol/L, all P<0.05] and HOMA2-IR [0.96 (0.82, 1.47), 1.20 (0.99, 1.43) vs. 1.34 (1.09, 1.51), all P<0.05] were significantly decreased in the RT and AT groups than in the control group. In addition, HOMA2-ß [84.50 (60.55, 107.33), 93.00 (78.60, 119.75) vs. 53.40 (37.70, 80.40), all P = 0.001] was significantly increased in the AT and RT groups compared with that in the control group. There were no significant differences in triglyceride (TG) and high-density lipoproteincholesterol (HDL-C) levels between the training groups and the control group (all P>0.05). After adjusting for age, sex and blood pressure, the cardiovascular risk of prediabetes was significantly reduced in RT (P =0.017) and AT groups (P =0.018). The Cox regression analyses showed that both the resistance training (HR=0.419, 95%CI =0.415-0.942, P=0.037) and the aerobic training (HR=0.310, 95%CI=0.447-0.866, P=0.026) were protective factors for cardiovascular disease in prediabetic patients after adjustment of age, sex, statins, body mass index and waist-to-hip ratio, which reduced the risks of cardiovascular disease in prediabetic patients by 58.1% and 69.0%, respectively. Conclusions: Two years of aerobic and resistance training interventions have obvious advantages on glycemic and insulin resistance control in prediabetes patients. The resistance training can reduce the risk of cardiovascular disease, and it is, thus, recommended for prediabetic patients without obvious exercise contraindications.


Asunto(s)
Enfermedades Cardiovasculares , Resistencia a la Insulina , Estado Prediabético , Entrenamiento de Fuerza , Glucemia , Índice de Masa Corporal , Enfermedades Cardiovasculares/prevención & control , China , Ejercicio Físico , Humanos , Estado Prediabético/terapia
18.
J Biol Chem ; 294(15): 6130-6141, 2019 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-30733338

RESUMEN

The tetrameric protein transthyretin is a transporter of retinol and thyroxine in blood, cerebrospinal fluid, and the eye, and is secreted by the liver, choroid plexus, and retinal epithelium, respectively. Systemic amyloid deposition of aggregated transthyretin causes hereditary and sporadic amyloidoses. A common treatment of patients with hereditary transthyretin amyloidosis is liver transplantation. However, this procedure, which replaces the patient's variant transthyretin with the WT protein, can fail to stop subsequent cardiac deposition, ultimately requiring heart transplantation. We recently showed that preformed amyloid fibrils present in the heart at the time of surgery can template or seed further amyloid aggregation of native transthyretin. Here we assess possible interventions to halt this seeding, using biochemical and EM assays. We found that chemical or mutational stabilization of the transthyretin tetramer does not hinder amyloid seeding. In contrast, binding of the peptide inhibitor TabFH2 to ex vivo fibrils efficiently inhibits amyloid seeding by impeding self-association of the amyloid-driving strands F and H in a tissue-independent manner. Our findings point to inhibition of amyloid seeding by peptide inhibitors as a potential therapeutic approach.


Asunto(s)
Neuropatías Amiloides Familiares , Amiloide , Péptidos/química , Prealbúmina , Agregado de Proteínas , Anciano , Anciano de 80 o más Años , Amiloide/antagonistas & inhibidores , Amiloide/química , Amiloide/genética , Amiloide/metabolismo , Neuropatías Amiloides Familiares/genética , Neuropatías Amiloides Familiares/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prealbúmina/antagonistas & inhibidores , Prealbúmina/química , Prealbúmina/genética , Prealbúmina/metabolismo
19.
Bioinformatics ; 35(21): 4397-4399, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30938757

RESUMEN

SUMMARY: Linked-read sequencing generates synthetic long reads which are useful for the detection and analysis of structural variants (SVs). The software associated with 10× Genomics linked-read sequencing, Long Ranger, generates the essential output files (BAM, VCF, SV BEDPE) necessary for downstream analyses. However, to perform downstream analyses requires the user to customize their own tools to handle the unique features of linked-read sequencing data. Here, we describe gemtools, a collection of tools for the downstream and in-depth analysis of SVs from linked-read data. Gemtools uses the barcoded aligned reads and the Megabase-scale phase blocks to determine haplotypes of SV breakpoints and delineate complex breakpoint configurations at the resolution of single DNA molecules. The gemtools package is a suite of tools that provides the user with the flexibility to perform basic functions on their linked-read sequencing output in order to address even more questions. AVAILABILITY AND IMPLEMENTATION: The gemtools package is freely available for download at: https://github.com/sgreer77/gemtools. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Asunto(s)
Programas Informáticos , Genómica , Secuenciación de Nucleótidos de Alto Rendimiento , Web Semántica , Análisis de Secuencia de ADN
20.
Opt Express ; 28(23): 34015-34023, 2020 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-33182879

RESUMEN

The beam splitters are essential optical components that are widely used in various optical instruments. The robustness of beam splitters is very necessary to all-optical networks. Here we report the design of the topologically protected beam splitter, whose splitting ratio can change flexibly to an arbitrary ratio, such as 50:50, 33:67, 25:75, based on the two-dimensional silicon photonic crystal slab. By using the 50:50 beam splitter, all major logic gates (OR, AND, NOT, XOR, NAND, XNOR, and NOR) are suitably designed with the linear interference approach. Additionally, these devices exhibit robustness even though some disorders exist. It is expected that these robust and compact devices are potentially applicable in optical computing and signal processing.

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