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1.
Cureus ; 16(3): e55682, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38586713

RESUMO

Objective This population-based cross-sectional study aimed to investigate the association between thyroid hormones and renal function in euthyroid Chinese individuals, as the relationship between thyroid hormones and renal function in this population remains unclear. Methods A total of 661 participants were included in the study after excluding individuals with thyroid diseases, incomplete clinical measurements, or those taking medications affecting thyroid function. Participants were categorized into three groups based on serum thyroid hormone and antibody levels. The study adjusted for covariates and assessed the glomerular filtration rate (GFR) and urine albumin-to-creatinine ratio (ACR) in relation to thyroid hormone levels. Results After adjusting for covariates, the study found a significant increase in GFR in the middle and highest tertiles of free triiodothyronine (FT3) and the highest tertile of total triiodothyronine (TT3). Serum FT3 and TT3 levels were significantly associated with GFR. Additionally, the study observed a significantly lower GFR in the highest tertile of thyroid-stimulating hormone (TSH) compared to the lowest tertile. However, thyroid hormone and antibody levels were not associated with the ACR. Furthermore, the highest tertiles of TT3 and total thyroxine (TT4) were associated with a decreased risk of chronic kidney disease (CKD). Conclusion In our study among euthyroid Chinese individuals, we observed a significant association between thyroid function and GFR. Specifically, lower FT3, TT3, and higher TSH were associated with reduced GFR, indicating a potential role for thyroid hormones in maintaining renal function. Furthermore, lower levels of TT3 and TT4 were associated with an increased risk of CKD. These findings suggest a direct link between thyroid and renal function, even in euthyroid individuals, emphasizing the need for further investigation to elucidate the underlying mechanisms and potential therapeutic implications.

2.
Cardiovasc Diabetol ; 23(1): 3, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172813

RESUMO

BACKGROUND: The triglyceride-glucose (TyG) index has been proposed as a surrogate marker of insulin resistance. However, the relationship between the TyG index and central blood pressure (BP), has not been well studied in adults. METHODS: A total of 715 Chinese adult participants were enrolled in this study. Anthropometric and BP were assessed. The TyG index was calculated as ln[fasting triglycerides(mg/dL) × fasting glucose(mg/dL)/2]. Central BP was measured using SphygmoCor system. RESULTS: The participants were stratified into three groups based on the TyG index, and significant differences were observed in metabolic and cardiovascular parameters and the prevalence of hypertension among the groups. Both brachial (ß = 1.38, P = 0.0310; group highest vs. lowest, ß = 2.66, P = 0.0084) and aortic (ß = 2.38, P = 0.0002; group highest vs. lowest, ß = 3.96, P = 0.0001) diastolic BP were significantly and independently associated with the TyG index and increasing TyG index tertile. However, there was no independent association between the TyG index and systolic BP. A one-unit increase in the TyG index was associated with a 46% higher risk of hypertension (P = 0.0121), and compared with the lowest group, participants in the highest group had a 95% higher risk of hypertension (P = 0.0057). CONCLUSIONS: Our study demonstrates a significant and independent association between the TyG index and both brachial and aortic diastolic BP in Chinese adults. Furthermore, the TyG index was found to be an independent predictor of hypertension.


Assuntos
Hipertensão , Resistência à Insulina , Adulto , Humanos , Glucose/metabolismo , Glicemia/metabolismo , Triglicerídeos , Pressão Sanguínea , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Biomarcadores , China/epidemiologia , Fatores de Risco
3.
Nat Commun ; 14(1): 6320, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37813844

RESUMO

Polymorphic structures of transition metal dichalcogenides (TMDs) host exotic electronic states, like charge density wave and superconductivity. However, the number of these structures is limited by crystal symmetries, which poses a challenge to achieving tailored lattices and properties both theoretically and experimentally. Here, we report a coloring-triangle (CT) latticed MoTe2 monolayer, termed CT-MoTe2, constructed by controllably introducing uniform and ordered mirror-twin-boundaries into a pristine monolayer via molecular beam epitaxy. Low-temperature scanning tunneling microscopy and spectroscopy (STM/STS) together with theoretical calculations reveal that the monolayer has an electronic Janus lattice, i.e., an energy-dependent atomic-lattice and a Te pseudo-sublattice, and shares the identical geometry with the Mo5Te8 layer. Dirac-like and flat electronic bands inherently existing in the CT lattice are identified by two broad and two prominent peaks in STS spectra, respectively, and verified with density-functional-theory calculations. Two types of intrinsic domain boundaries were observed, one of which maintains the electronic-Janus-lattice feature, implying potential applications as an energy-tunable electron-tunneling barrier in future functional devices.

5.
Phys Rev Lett ; 129(4): 049901, 2022 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-35939036

RESUMO

This corrects the article DOI: 10.1103/PhysRevLett.127.176401.

6.
Phys Rev Lett ; 127(17): 176401, 2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34739291

RESUMO

Multifold degenerate fermions have attracted a lot of research interest in condensed matter physics and materials science, but always lack in two dimensions. In this Letter, from symmetry analysis and lattice model construction, we demonstrate that eightfold degenerate fermions can be realized in two-dimensional systems. In nonmagnetic materials with negligible spin-orbit coupling, the gray magnetic space groups together with SU(2) spin rotation symmetry can protect the two-dimensional eightfold degenerate fermions on a certain high-symmetry axis in the Brillouin zone, no matter whether the system is centrosymmetric or noncentrosymmetric. In antiferromagnetic materials, the eightfold degenerate fermions can also be protected by certain "spin space groups." Furthermore, by first-principles electronic structure calculations, we predict that the paramagnetic phase of the monolayer LaB_{8} on a suitable substrate is a two-dimensional eightfold degenerate as well as Dirac node-line semimetal. Especially, the eightfold degenerate points are close to the Fermi level, which makes monolayer LaB_{8} a good platform to study the exotic physical properties of two-dimensional eightfold degenerate fermions.

7.
Phys Rev Lett ; 127(12): 127205, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34597084

RESUMO

We study the effect of Dzyaloshinskii-Moriya (DM) interaction on the triangular lattice U(1) quantum spin liquid (QSL) which is stabilized by ring-exchange interactions. A weak DM interaction introduces a staggered flux to the U(1) QSL state and changes the density of states at the spinon Fermi surface. If the DM vector contains in-plane components, then the spinons gain nonzero Berry phase. The resultant thermal conductances κ_{xx} and κ_{xy} qualitatively agree with the experimental results on the material EtMe_{3}Sb[Pd(dmit)_{2}]_{2}. Furthermore, owing to perfect nesting of the Fermi surface, a spin density wave state is triggered by larger DM interactions. On the other hand, when the ring-exchange interaction decreases, another antiferromagnetic (AFM) phase with 120° order shows up which is proximate to a U(1) Dirac QSL. We discuss the difference of the two AFM phases from their static structure factors and excitation spectra.

8.
Nat Commun ; 12(1): 4007, 2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34188044

RESUMO

The frustrated magnet α-RuCl3 constitutes a fascinating quantum material platform that harbors the intriguing Kitaev physics. However, a consensus on its intricate spin interactions and field-induced quantum phases has not been reached yet. Here we exploit multiple state-of-the-art many-body methods and determine the microscopic spin model that quantitatively explains major observations in α-RuCl3, including the zigzag order, double-peak specific heat, magnetic anisotropy, and the characteristic M-star dynamical spin structure, etc. According to our model simulations, the in-plane field drives the system into the polarized phase at about 7 T and a thermal fractionalization occurs at finite temperature, reconciling observations in different experiments. Under out-of-plane fields, the zigzag order is suppressed at 35 T, above which, and below a polarization field of 100 T level, there emerges a field-induced quantum spin liquid. The fractional entropy and algebraic low-temperature specific heat unveil the nature of a gapless spin liquid, which can be explored in high-field measurements on α-RuCl3.

9.
Phys Rev Lett ; 123(19): 197201, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31765175

RESUMO

In addition to the Kitaev (K) interaction, candidate Kitaev materials also possess Heisenberg (J) and off-diagonal symmetric (Γ) couplings. We investigate the quantum (S=1/2) K-J-Γ model on the honeycomb lattice by a variational Monte Carlo method. In addition to the "generic" Kitaev spin liquid (KSL), we find that there is just one proximate KSL (PKSL) phase, while the rest of the phase diagram contains different magnetically ordered states. The PKSL is a gapless Z_{2} state with 14 Majorana cones, which in contrast to the KSL has a gapless spin response. In a magnetic field applied normal to the honeycomb plane, it realizes two of Kitaev's gapped chiral spin-liquid phases, of which one is non-Abelian with Chern number ν=5 and the other is Abelian with ν=4. These two phases could be distinguished by their thermal Hall conductance.

10.
Stem Cell Reports ; 11(1): 171-182, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29910127

RESUMO

Clinical application of stem cell derivatives requires clinical-grade cells and sufficient preclinical proof of safety and efficacy, preferably in primates. We previously successfully established a clinical-grade human parthenogenetic embryonic stem cell (hPESC) line, but the suitability of its subtype-specific progenies for therapy is not clear. Here, we compared the function of clinical-grade hPESC-derived midbrain dopaminergic (DA) neurons in two canonical protocols in a primate Parkinson's disease (PD) model. We found that the grafts did not form tumors and produced variable but apparent behavioral improvement for at least 24 months in most monkeys in both groups. In addition, a slight DA increase in the striatum correlates with significant functional improvement. These results demonstrated that clinical-grade hPESCs can serve as a reliable source of cells for PD treatment. Our proof-of-concept findings provide preclinical data for China's first ESC-based phase I/IIa clinical study of PD (ClinicalTrials.gov number NCT03119636).


Assuntos
Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/fisiologia , Células-Tronco Embrionárias/citologia , Locomoção , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Animais , Comportamento Animal , Biomarcadores , Encéfalo/citologia , Encéfalo/metabolismo , Diferenciação Celular , Linhagem Celular , Movimento Celular , Sobrevivência Celular , Transformação Celular Neoplásica , Terapia Baseada em Transplante de Células e Tecidos , Modelos Animais de Doenças , Dopamina/metabolismo , Humanos , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Doença de Parkinson/etiologia , Fenótipo , Primatas , Putamen/metabolismo , Putamen/fisiopatologia
11.
Phys Rev Lett ; 120(18): 187201, 2018 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-29775347

RESUMO

Motivated by recent experimental observations in α-RuCl_{3}, we study the K-Γ model on the honeycomb lattice in an external magnetic field. By a slave-particle representation and variational Monte Carlo calculations, we reproduce the phase transition from zigzag magnetic order to a field-induced disordered phase. The nature of this state depends crucially on the field orientation. For particular field directions in the honeycomb plane, we find a gapless Dirac spin liquid, in agreement with recent experiments on α-RuCl_{3}. For a range of out-of-plane fields, we predict the existence of a Kalmeyer-Laughlin-type chiral spin liquid, which would show an integer-quantized thermal Hall effect.

12.
Phys Rev Lett ; 119(22): 227208, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29286810

RESUMO

α-RuCl_{3} is a leading candidate material for the observation of physics related to the Kitaev quantum spin liquid (QSL). By combined susceptibility, specific-heat, and nuclear-magnetic-resonance measurements, we demonstrate that α-RuCl_{3} undergoes a quantum phase transition to a QSL in a magnetic field of 7.5 T applied in the ab plane. We show further that this high-field QSL phase has gapless spin excitations over a field range up to 16 T. This highly unconventional result, unknown in either Heisenberg or Kitaev magnets, offers insight essential to establishing the physics of α-RuCl_{3}.

13.
Phys Rev Lett ; 119(18): 185701, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29219568

RESUMO

We discuss the quantum simulation of symmetry-protected topological (SPT) states for interacting fermions in quasi-one-dimensional gases of alkaline-earth-like atoms such as ^{173}Yb. Taking advantage of the separation of orbital and nuclear-spin degrees of freedom in these atoms, we consider Raman-assisted spin-orbit couplings in the clock states, which, together with the spin-exchange interactions in the clock-state manifolds, give rise to SPT states for interacting fermions. We numerically investigate the phase diagram of the system, and study the phase transitions between the SPT phase and the symmetry-breaking phases. The interaction-driven topological phase transition can be probed by measuring local density distribution of the topological edge modes.

14.
Stem Cell Reports ; 9(1): 366-380, 2017 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-28506532

RESUMO

Human embryonic stem cells (hESCs) are promising in regenerative medicine. Although several hESC-based clinical trials are under way, a widely accepted standard of clinical-grade cells remains obscure. To attain a completely xeno-free clinical-grade cell line, the system must be free of xenogenic components, the cells must have a comprehensive set of functions, and good manufacturing practice conditions must be used. In this study, following these criteria, we successfully derived two hESC lines, which were thereby considered "clinical-grade embryonic stem cells". In addition to the primary capacity for pluripotency, these two cell lines were efficiently differentiated into various types of clinical-grade progeny. Importantly, the cells were recognized by the National Institutes for Food and Drug Control of China for further eligible accreditation. These data indicate that we have established completely xeno-free clinical-grade hESC lines and their derivatives, which will be valuable for the foundation of an international standard for clinical-grade cells for therapy.


Assuntos
Separação Celular/métodos , Células-Tronco Embrionárias Humanas/citologia , Animais , Técnicas de Cultura de Células/métodos , Técnicas de Cultura de Células/normas , Diferenciação Celular , Linhagem da Célula , Separação Celular/normas , Sobrevivência Celular , Células Cultivadas , China , Criopreservação , Neurônios Dopaminérgicos/citologia , Neurônios Dopaminérgicos/metabolismo , Feminino , Células-Tronco Embrionárias Humanas/metabolismo , Humanos , Fígado/citologia , Fígado/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese , Ratos Sprague-Dawley , Esterilização/métodos , Esterilização/normas
15.
Chin J Traumatol ; 19(6): 348-352, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28088940

RESUMO

PURPOSE: To describe an indirect reduction technique during minimally invasive percutaneous plate osteosynthesis (MIPPO) of tibial shaft fractures with the use of a distraction support. METHODS: Between March 2011 and October 2014, 52 patients with a mean age of 48 years (16-72 years) sustaining tibial shaft fractures were included. All the patients underwent MIPPO for the fractures using a distraction support prior to insertion of the plate. Fracture angular deformity was assessed by goni- ometer measurement on preoperative and postoperative images. RESULTS: Preoperative radiographs revealed a mean of 7.6°(1.2°-28°) angulation in coronal plane and a mean of 6.8°(0.5°-19°) angulation in sagittal plane. Postoperative anteroposterior and lateral radio- graphs showed a mean of 0.8°(0°-4.0°) and 0.6°(0°-3.6°) of varus/valgus and apex anterior/posterior angulation, respectively. No intraoperative or postoperative complications were noted. CONCLUSIONS: This study suggests that the distraction support during MIPPO of tibial shaft fractures is an effective and safe method with no associated complications.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Fraturas da Tíbia/cirurgia , Adolescente , Adulto , Idoso , Fixação Interna de Fraturas/efeitos adversos , Humanos , Pessoa de Meia-Idade
16.
Zhongguo Gu Shang ; 28(4): 340-4, 2015 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-26072617

RESUMO

OBJECTIVE: To explore the operation methods and clinical effects of transfer of the medial half of the coracoacromial ligament to reconstruct the coracoclavicular ligament in treating complete acromioclavicular joint dislocation. METHODS: From January 2006 to June 2012,26 patients with acute complete acromioclavicular joint dislocation underwent surgery. Transfer of the medial half of the coracoacromial ligament to reconstruct the coracoclavicular ligament, additional clavical hoot plate and Kirschner wires fixation, were performed in all the patients. Among the patients, 18 patients were male and 8 patients were female, with an average age of 36.7 years old (ranged from 25 to 51 years). The duration from injury to operation was from 3 to 12 days with an average of 5 days. According to the Rockwood classification, 4 cases were grade III and 22 cases were grade V . Clinical manifestation included local swelling, tenderness with snapping, limitation of shoulder joint motion. In preoperative bilateral shoulder joint X-rays, the injured coracoclavicular distance was (16.2 ± 5.0) mm which was significantly wider than that of uninjured sides (7.6 ± 1.0) mm. Clinical results were evaluated according to X-rays and Constant-Murley score. RESULTS: All incisions obtained primary healing after operation without complication of infection, internal fixation breakage, redislocation. All the patients were followed up from 12 to 30 months with an average of 18 months. Kirschner wires and internal fixation plate were removed at 1 month and 8-10 months after operation, respectively. At final follow-up, the motion of shoulder joint recovered to normal and a no pain joint was obtained. According to Constant-Murley score, 24 cases got excellent results and 2 cases good. There was no significant difference after operation between the injured coracoclavicular distance and the uninjured contralateral side [(7.7 ± 1.2) mm vs (7.6 ± 1.0) mm), P > 0.05]. CONCLUSION: Transfer of the medial half of the coracoacromial ligament to reconstruct the coracoclavicular ligament, additional fixation using hook plate and Kirschner wires is the effective surgical method in treating complete acute acromioclavicular joint dislocation.


Assuntos
Articulação Acromioclavicular/lesões , Luxações Articulares/cirurgia , Ligamentos Articulares/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
18.
Phys Rev Lett ; 113(26): 267206, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615382

RESUMO

It is well known that a bosonic Mott insulator can be realized by condensing vortices of a boson condensate. Usually, a vortex becomes an antivortex (and vice versa) under time reversal symmetry, and the condensation of vortices results in a trivial Mott insulator. However, if each vortex or antivortex interacts with a spin trapped at its core, the time reversal transformation of the composite vortex operator will contain an extra minus sign. It turns out that such a composite vortex condensed state is a bosonic topological insulator (BTI) with gapless boundary excitations protected by U(1)⋊Z2(T) symmetry. We point out that in BTI, an external π-flux monodromy defect carries a Kramers doublet. We propose lattice model Hamiltonians to realize the BTI phase, which might be implemented in cold atom systems or spin-1 solid state systems.

19.
Phys Rev Lett ; 110(6): 067205, 2013 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-23432300

RESUMO

Symmetry-protected topological (SPT) states are short-range entangled states with symmetry. Nontrivial SPT states have symmetry-protected gapless edge excitations. In 2 dimension (2D), there are an infinite number of nontrivial SPT phases with SU(2) or SO(3) symmetry. These phases can be described by SU(2) or SO(3) nonlinear-sigma models with a quantized topological θ term. At an open boundary, the θ term becomes the Wess-Zumino-Witten term and consequently the boundary excitations are decoupled gapless left movers and right movers. Only the left movers (if θ>0) carry the SU(2) or SO(3) quantum numbers. As a result, the SU(2) SPT phases have a half-integer quantized spin Hall conductance and the SO(3) SPT phases have an even-integer quantized spin Hall conductance. Both the SU(2) and SO(3) SPT phases are symmetric under their U(1) subgroup and can be viewed as U(1) SPT phases with even-integer quantized Hall conductance.

20.
Phys Rev Lett ; 110(7): 076401, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25166386

RESUMO

We propose to observe and manipulate topological edge spins in a one-dimensional optical lattice based on currently available experimental platforms. Coupling the atomic spin states to a laser-induced periodic Zeeman field, the lattice system can be driven into a symmetry protected topological (SPT) phase, which belongs to the chiral unitary (AIII) class protected by particle number conservation and chiral symmetries. In the free-fermion case the SPT phase is classified by a Z invariant which reduces to Z(4) with interactions. The zero edge modes of the SPT phase are spin polarized, with left and right edge spins polarized to opposite directions and forming a topological spin qubit (TSQ). We demonstrate a novel scheme to manipulate the zero modes and realize single spin control in an optical lattice. The manipulation of TSQs has potential applications to quantum computation.

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