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1.
Zhonghua Yan Ke Za Zhi ; 60(4): 343-351, 2024 Apr 11.
Artigo em Zh | MEDLINE | ID: mdl-38583058

RESUMO

Objective: The aim of this paper is to compare the refractive correction effects of rigid gas permeable contact lenses (RGPCL) and spectacle correction in children with aphakia after congenital cataract surgery. Methods: This was a prospective non-randomized controlled trial. Children with aphakic eyes after congenital cataract surgery, who underwent vision correction in the Strabismus and Pediatric Ophthalmology Clinic of Beijing Tongren Hospital affiliated with Capital Medical University from April 2012 to November 2019, were continuously collected. Those who voluntarily chose to wear RGPCL for refractive correction were included in the experimental group. Patients with monocular disease were in trial group 1, and patients with binocular disease were in trial group 2. Patients who chose to wear frame glasses for refractive correction were included in the control group. Patients with monocular disease were in control group 1, and patients with binocular disease were in control group 2. Regional origin, medical history, and family information were collected at the first diagnosis. During the follow-up, adverse reactions occurring during the process of wearing glasses were recorded. The Teller acuity card was used for visual examination to obtain the best-corrected visual acuity and convert it into the logarithm of the minimum resolution angle. The degree of nystagmus was determined according to the amplitude and frequency of nystagmus. Treatment cost, treatment compliance, and the reasons for adopting or not adopting RGPCL were analyzed through a questionnaire completed by the parents of children with RGPCL. Results: A total of 203 children (344 eyes) who underwent congenital cataract surgery were included, including 124 males (210 eyes) and 79 females (134 eyes). The age range was 3 to 36 months. There were 28 cases in the experimental group, including 19 cases in trial group 1 and 9 cases in trial group 2. There were 175 cases in the control group, including 43 cases in control group 1 and 132 cases in control group 2. Except for 6 months of age, the visual acuity of the experimental group was better than that of the control group, and the differences were statistically significant (P<0.05). The visual acuity of children in trial group 1 was better than that of children in control group 1 at the same age. Among them, at 12 months of age [1.54 (1.27, 1.97), 1.84 (0.97, 2.12)], 18 months of age [1.27 (0.97, 1.84), 1.84 (0.97, 2.12)], 24 months of age [1.54 (1.27, 1.84), 1.84 (0.97, 2.12)], and 30 months old [0.97 (0.66, 1.27), 1.54 (0.66, 2.12)], the difference was statistically significant (P<0.001). The visual acuity of children in trial group 2 was better than that in control group 2 at the same age. Among them, at 18 months old [1.27 (0.97, 1.54), 1.27 (0.66, 2.12)], 24 months old [0.97 (0.66, 1.27), 1.27 (0.66, 2.12)], and 30 months old [1.27 (0.66, 2.12)], the difference was statistically significant (P<0.05). The remission rate of nystagmus in the experimental group was 8/9 (8 cases), the remission rate of nystagmus in the control group was 34.40% (32 cases), and the exacerbation rate was 29.03% (27 cases). The average annual cost of the experimental group was 25 125 yuan, and that of the control group was 2 511 yuan. Conclusions: RGPCL is a well-tolerated, safe, and effective treatment for infants and young children. The visual acuity and degree of nystagmus were significantly improved in children who wore RGPCL for aphakia refractive correction after congenital cataract surgery compared with spectacle correction.


Assuntos
Afacia , Extração de Catarata , Catarata , Lentes de Contato , Nistagmo Patológico , Oftalmologia , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Catarata/terapia , Catarata/congênito , Óculos , Estudos Prospectivos
2.
Zhonghua Gan Zang Bing Za Zhi ; 31(9): 961-968, 2023 Sep 20.
Artigo em Zh | MEDLINE | ID: mdl-37872092

RESUMO

Objective: To compare the differences in the prevalence of mild micro-hepatic encephalopathy (MHE) among patients with cirrhosis by using the psychometric hepatic encephalopathy score (PHES) and the Stroop smartphone application (Encephal App) test. Methods: This prospective, multi-center, real-world study was initiated by the National Clinical Medical Research Center for Infectious Diseases and the Portal Hypertension Alliance and registered with International ClinicalTrials.gov (NCT05140837). 354 cases of cirrhosis were enrolled in 19 hospitals across the country. PHES (including digital connection tests A and B, digital symbol tests, trajectory drawing tests, and serial management tests) and the Stroop test were conducted in all of them. PHES was differentiated using standard diagnostic criteria established by the two studies in China and South Korea. The Stroop test was evaluated based on the criteria of the research and development team. The impact of different diagnostic standards or methods on the incidence of MHE in patients with cirrhosis was analyzed. Data between groups were differentiated using the t-test, Mann-Whitney U test, and χ (2) test. A kappa test was used to compare the consistency between groups. Results: After PHES, the prevalence of MHE among 354 cases of cirrhosis was 78.53% and 15.25%, respectively, based on Chinese research standards and Korean research normal value standards. However, the prevalence of MHE was 56.78% based on the Stroop test, and the differences in pairwise comparisons among the three groups were statistically significant (kappa = -0.064, P < 0.001). Stratified analysis revealed that the MHE prevalence in three groups of patients with Child-Pugh classes A, B, and C was 74.14%, 83.33%, and 88.24%, respectively, according to the normal value standards of Chinese researchers, while the MHE prevalence rates in three groups of patients with Child-Pugh classes A, B, and C were 8.29%, 23.53%, and 38.24%, respectively, according to the normal value standards of Korean researchers. Furthermore, the prevalence rates of MHE in the three groups of patients with Child-Pugh grades A, B, and C were 52.68%, 58.82%, and 73.53%, respectively, according to the Stroop test standard. However, among the results of each diagnostic standard, the prevalence of MHE showed an increasing trend with an increasing Child-Pugh grade. Further comparison demonstrated that the scores obtained by the number connection test A and the number symbol test were consistent according to the normal value standards of the two studies in China and South Korea (Z = -0.982, -1.702; P = 0.326, 0.089), while the other three sub-tests had significant differences (P < 0.001). Conclusion: The prevalence rate of MHE in the cirrhotic population is high, but the prevalence of MHE obtained by using different diagnostic criteria or methods varies greatly. Therefore, in line with the current changes in demographics and disease spectrum, it is necessary to enroll a larger sample size of a healthy population as a control. Moreover, the establishment of more reliable diagnostic scoring criteria will serve as a basis for obtaining accurate MHE incidence and formulating diagnosis and treatment strategies in cirrhotic populations.


Assuntos
Encefalopatia Hepática , Humanos , Encefalopatia Hepática/diagnóstico , Encefalopatia Hepática/epidemiologia , Encefalopatia Hepática/etiologia , Estudos Prospectivos , Índice de Gravidade de Doença , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico , Psicometria/métodos
3.
Zhonghua Yi Xue Za Zhi ; 102(22): 1660-1665, 2022 Jun 14.
Artigo em Zh | MEDLINE | ID: mdl-35692018

RESUMO

Objectives: To investigate the feasibility of using a porcine fibrin sealant to wrap and remove kidney calculi fragments through an isolated porcine kidney model. Methods: In the isolated porcine kidney stone model (implanted with 100 mg, air dried, ≤1 mm human stone fragments, n=6;implanted with 100 mg, air dried, ≤3 mm human stone fragments, n=6), the ureteral soft mirror combined with the 12/14Fr UAS was used to test the effect of stone extraction using only two stone extraction methods: basket extraction (control group, ≤1 mm stone fragments, n=3; ≤3 mm stone fragments, n=3) and basket-sealant extraction (test group, ≤1 mm stone fragments, n=3; ≤3 mm stone fragments, n=3). Compare the stone removal rate and operation time of the two stone retrieval methods. The sealant was put into urine of normal human and observed. Results: Porcine Fibrin Sealant can form a gel in saline and urine and adhere and wrap stone fragments. The time of procedures of test (basket-sealant) and control (basket) group in kidneys implanted with ≤ 1 mm stone fragments were (14.0±4.2) and (29.0±0.7)min (P<0.05) stone clearance rates were (90.9±1.4)% and (48.4±15.7)% (P<0.05), respectively. In kidneys implanted with ≤ 3 mm fragments, time of procedures were (12.8±4.0) and (30.0±0)min (P<0.05) Stone clearance rates were (91.1±5.0)% and (20.7±8.0)% (P<0.05). The Sealant dissolves by itself in normal human urine and normal saline at 37 ℃ for 24 hours. Conclusion: The appropriate concentration of Porcine Fibrin Sealant assisted stone retrieval may become a new method for removing small stone fragments in retrograde intrarenal surgery.


Assuntos
Cálculos Renais , Litotripsia , Cálculos Ureterais , Animais , Adesivo Tecidual de Fibrina , Rim , Cálculos Renais/cirurgia , Suínos , Cálculos Ureterais/terapia , Ureteroscopia/métodos
4.
Phys Rev Lett ; 126(24): 247001, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34213920

RESUMO

CsV_{3}Sb_{5} is a newly discovered Z_{2} topological kagome metal showing the coexistence of a charge-density-wave (CDW)-like order at T^{*}=94 K and superconductivity (SC) at T_{c}=2.5 K at ambient pressure. Here, we study the interplay between CDW and SC in CsV_{3}Sb_{5} via measurements of resistivity, dc and ac magnetic susceptibility under various pressures up to 6.6 GPa. We find that the CDW transition decreases with pressure and experience a subtle modification at P_{c1}≈0.6-0.9 GPa before it vanishes completely at P_{c2}≈2 GPa. Correspondingly, T_{c}(P) displays an unusual M-shaped double dome with two maxima around P_{c1} and P_{c2}, respectively, leading to a tripled enhancement of T_{c} to about 8 K at 2 GPa. The obtained temperature-pressure phase diagram resembles those of unconventional superconductors, illustrating an intimated competition between CDW-like order and SC. The competition is found to be particularly strong for the intermediate pressure range P_{c1}≤P≤P_{c2} as evidenced by the broad superconducting transition and reduced superconducting volume fraction. The modification of CDW order around P_{c1} has been discussed based on the band structure calculations. This work not only demonstrates the potential to raise T_{c} of the V-based kagome superconductors, but also offers more insights into the rich physics related to the electron correlations in this novel family of topological kagome metals.

5.
Phys Rev Lett ; 124(13): 137201, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32302196

RESUMO

The ternary AMnBi_{2} (A is alkaline as well as rare-earth atom) materials provide an arena for investigating the interplay between low-dimensional magnetism of the antiferromagnetic MnBi layers and the electronic states in the intercalated Bi layers, which harbor relativistic fermions. Here, we report on a comprehensive study of the optical properties and magnetic torque response of Ca_{1-x}Na_{x}MnBi_{2}. Our findings give evidence for a spin canting occurring at T_{s}∼50-100 K. With the support of first-principles calculations we establish a direct link between the spin canting and the reconstruction of the electronic band structure, having immediate implications for the spectral weight reshuffling in the optical response, signaling a partial gapping of the Fermi surface, and the dc transport properties below T_{s}.

6.
J Biol Regul Homeost Agents ; 34(4): 1317-1324, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32924373

RESUMO

The purpose of this study was to investigate the expression and mechanism of miR-17 in gastric lym-phoma. miR-17mimics, miR-17 inhibitors and negative controls were transfected into human gastric lymphoma cell line cyp6d. The proliferation, invasion and apoptosis of cyp6d cells were detected by CCK-8, Transwell and TUNEL methods, respectively. The expression and clinicopathological features of miR-17 in gastric lymphoma were analyzed by real-time quantitative PCR. The target gene of miR-17 was predicted by targetscan 7.2, and the expression of miR-17 related protein was detected by Western blot. The results showed that the expression of miR-17 in gastric lymphoma was significantly higher than that in normal tissues (P < 0.05), which was closely related to lymph node metastasis, tumor size and distant metastasis (P < 0.05). The high expression of miR-17 significantly promoted the proliferation and invasion of cyp6d cells and inhibited apoptosis (P < 0.05). The high expression of miR-17 can regu¬late the expression of HSP60 and TNFR2. It has been found that miR-17 can promote the development of gastric lymphoma by regulating HSP60/TNFR2 pathway, which is a potential molecular target for the diagnosis and treatment of gastric lymphoma.


Assuntos
MicroRNAs/genética , Neoplasias Gástricas , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Chaperonina 60 , Regulação Neoplásica da Expressão Gênica , Humanos , Linfoma não Hodgkin , Proteínas Mitocondriais , Invasividade Neoplásica/genética , Receptores Tipo II do Fator de Necrose Tumoral , Neoplasias Gástricas/genética
7.
J Biol Regul Homeost Agents ; 30(1): 135-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27049084

RESUMO

This study explores the effects of sodium ferrous chlorophyll treatment on the anemia of maintenance hemodialysis (MHD) patients, as well as the relevant biochemical parameters. We selected 72 patients who had received regular MHD treatment two or three times a week for more than 3 months in the Hospital of Traditional Chinese Medicine of Zhengzhou City of Henan Province from March 2014 to March 2016. They were equally divided into a treatment group and a control group. Haemoglobin (HB) and hematocrit (HCT) of the treatment group increased significantly after treatment (p < 0.01), but less in the control group (p < 0.05); Also serum ferritin (SF) and transferrin saturation (TAST) of the treatment group increased significantly after treatment (p < 0.01); SF of the control group also increased significantly (p < 0.01) and TAST of the control group increased (p < 0.05) but less than in the treatment group. No obvious changes of serum creatinine (SCR), blood urea nitrogen (BUN), C-reactive protein (CRP) and superoxide dismutase (SOD) were found in either groups after treatment (p>0.05). Albumin (ALB) dosage of the treatment group increased after treatment (p < 0.05) while hemopoietin (EPO) decreased significantly (p < 0.01). ALB and EPO of the control group had no obvious changes after treatment (p>0.05). ALB level of the treatment group increased more significantly than in the control group (p < 0.05), while EPO dosage decreased more significantly than in the control group (p <0.05). Therefore, the combination of conventional western medicine and sodium ferrous chlorophyll can effectively improve anemia conditions of MHD patients and their quality of life.


Assuntos
Anemia/tratamento farmacológico , Clorofila/uso terapêutico , Diálise Renal , Albuminas/metabolismo , Anemia/sangue , Nitrogênio da Ureia Sanguínea , Proteína C-Reativa/metabolismo , Creatinina/sangue , Eritropoetina/metabolismo , Feminino , Ferritinas/sangue , Hematócrito , Hemoglobinas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Superóxido Dismutase/metabolismo , Transferrina/metabolismo , Resultado do Tratamento
8.
J Biol Regul Homeost Agents ; 30(2): 535-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27358145

RESUMO

To explore the reactivity of patients with renal anemia (MHD) to erythropoietin (EPO) in maintenance hemodialysis (HD), 31 patients were enrolled in this study. According to the level of serum ferritin (SF), they were divided into two groups; one group received treatment using recombinant human erythropoietin (rHuEPO) and the other group was given iron sucrose. Taking terminal EPO dosage, terminal erythropoietin resistance index (ERI) and rate of change of ERI (ΔERII) as target indexes, the influence of SF level on dosage of EPO was evaluated after usage conditions of relevant substances in a 3-month period. The results revealed that differences of dialysis age, albumin (ALB), blood calcium, initial and terminal SF, variable quantity of hemoglobin (Hb), terminal EPO and ERI between two groups had statistical significance. Furthermore, SF level and terminal EPO (r = -0.37, P < 0. 05) as well as SF level and terminal ERI (r = - 0.39, P <0.05) were negatively correlated. Difference of terminal ERI between the two groups had statistical significance. It can therefore be summarized that supplementing an iron agent intravenously to maintain SF level between 500 ng/ml and 1200 ng/ml may improve reactivity of patients with MHD to EPO. In addition, rHuEPO therapy in treating anemia of patients with MHD has the same effect with intravenous drug delivery, less side effects and is easy to administer.


Assuntos
Anemia/tratamento farmacológico , Eritropoetina/uso terapêutico , Falência Renal Crônica/complicações , Diálise Renal , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia/sangue , Feminino , Ferritinas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/uso terapêutico
10.
Genet Mol Res ; 14(2): 3098-105, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25966074

RESUMO

The gene for the nucleocapsid (N) protein of canine distemper virus was cloned into the pMD-18T vector, and positive recombinant plasmids were obtained by enzyme digestion and sequencing. After digestion by both EcoRI and KpnI, the plasmid was directionally cloned into the eukaryotic expression vector pcDNA; the positive clone pcDNA-N was screened by electrophoresis and then transfected into COS-7 cells. Immunofluorescence analysis results showed that the canine distemper virus N protein was expressed in the cytoplasm of transfected COS-7 cells. After emulsification in Freund's adjuvant, the recombinant plasmid pcDNA-N was injected into the abdominal cavity of 8-week-old BABL/c mice, with the pcDNA original vector used as a negative control. Mice were immunized 3 times every 2 weeks. The blood of immunized mice was drawn 2 weeks after completing the immunizations to measure titer levels. The antibody titer in the pcDNA-N test was 10(1.62 ± 0.164), while in the control group this value was 10(0.52 ± 0.56), indicating that specific humoral immunity was induced in canine distemper virus nucleocapsid protein-immunized mice.


Assuntos
Vírus da Cinomose Canina/genética , Vírus da Cinomose Canina/imunologia , Animais , Anticorpos Antivirais/sangue , Clonagem Molecular , Cães , Feminino , Imunização/veterinária , Camundongos , Camundongos Endogâmicos BALB C , Proteínas do Nucleocapsídeo/genética , Vacinas Virais/imunologia
11.
Phys Rev Lett ; 112(10): 107001, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24679321

RESUMO

Single-layer FeSe films with an extremely expanded in-plane lattice constant of 3.99±0.02 Å are fabricated by epitaxially growing FeSe/Nb:SrTiO3/KTaO3 heterostructures and studied by in situ angle-resolved photoemission spectroscopy. Two elliptical electron pockets at the Brillouin zone corner are resolved with negligible hybridization between them, indicating that the symmetry of the low-energy electronic structure remains intact as a freestanding single-layer FeSe, although it is on a substrate. The superconducting gap closes at a record high temperature of 70 K for the iron-based superconductors. Intriguingly, the superconducting gap distribution is anisotropic but nodeless around the electron pockets, with minima at the crossings of the two pockets. Our results place strong constraints on current theories.

12.
Genet Mol Res ; 13(3): 7388-97, 2014 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-25222237

RESUMO

This study aimed to prepare monoclonal antibody of feline calicivirus (FCV) and identify its basic biological characteristics. Saturated ammonium sulfate precipitation, combined differential centrifugation, and cesium chloride density gradient centrifugation were used for the purification of FCV. The purified FCV was used as antigen to immunize BALB/c mice. The hybridoma lines of anti-FCV monoclonal antibodies were established using cell fusion and hybridoma screening techniques. The subtypes of the monoclonal antibody were identified. The results showed that 3 strains of hybridoma cell lines stably secreted anti-FCV monoclonal antibody; they were named as D8, E5, and H4. The D8 and E5 were IgM subtype antibodies, and H4 was IgG2b subtype antibody. The monoclonal antibody obtained shared no cross-reactivity with feline parvovirus, canine parvovirus, and canine distemper virus. According to the different recognition sites of 2 monoclonal antibodies E5 and H4 to the FCV, they were used to coat microtiter plates and prepare 2 enzyme-labeled secondary antibodies to establish double-antibody sandwich enzyme-linked immunosorbent assay detecting method.


Assuntos
Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/isolamento & purificação , Calicivirus Felino/imunologia , Ensaio de Imunoadsorção Enzimática , Animais , Especificidade de Anticorpos/imunologia , Calicivirus Felino/ultraestrutura , Gatos , Linhagem Celular , Feminino , Hibridomas/imunologia , Hibridomas/metabolismo , Cariotipagem , Camundongos
13.
Eur Rev Med Pharmacol Sci ; 27(16): 7576-7581, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37667934

RESUMO

OBJECTIVE: Due to the impact of excessive glucose on osteogenic differentiation, diabetic osteopathy frequently results in skeletal fragility, osteoporosis, and bone pain. Zoledronic acid, a bisphosphonate (BP) that effectively inhibits osteoclastic bone resorption is given yearly to improve bone mineral density (BMD) in patients with osteoporosis. However, the detailed molecular mechanisms remained unclear. This study investigates the possible pathways by which zoledronic acid regulates osteogenesis when blood glucose levels are high. MATERIALS AND METHODS: MC3T3-E1 cells were treated with one mM zoledronic acid or not in a standard or high glucose culture medium. A quantitative polymerase chain reaction (qPCR) assay was utilized to assess the expression of the target candidate genes, including RUNX2, MALAT1, miR-133, miR-20a, and miR-204. RESULTS: In a high-glucose condition, zoledronic acid treatment significantly lowered MALAT1 (p < 0.0001) and miR-20a (p < 0.0001) expression. Conversely, in a high-glucose condition, RUNX2, miR-133, and miR-204 expressions were found to be significantly increased in the zoledronic acid treatment group as compared to no treatment (all p < 0.0001). CONCLUSIONS: In conclusion, under a high-glucose environment, zoledronic acid can modulate the expression of the RUNX2 transcription factor through epigenetic regulation.


Assuntos
Reabsorção Óssea , MicroRNAs , Osteoporose , RNA Longo não Codificante , Humanos , Ácido Zoledrônico/farmacologia , Osteogênese , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Epigênese Genética , Diferenciação Celular , Osteoporose/tratamento farmacológico , Osteoporose/genética , Glucose , MicroRNAs/genética
14.
Nat Mater ; 10(4): 273-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21358648

RESUMO

Pairing symmetry is a fundamental property that characterizes a superconductor. For the iron-based high-temperature superconductors, an s(±)-wave pairing symmetry has received increasing experimental and theoretical support. More specifically, the superconducting order parameter is an isotropic s-wave type around a particular Fermi surface, but it has opposite signs between the hole Fermi surfaces at the zone centre and the electron Fermi surfaces at the zone corners. Here we report the low-energy electronic structure of the newly discovered superconductors, A(x)Fe(2)Se(2) (A=K,Cs) with a superconducting transition temperature (Tc) of about 30 K. We found A(x)Fe(2)Se(2) (A=K,Cs) is the most heavily electron-doped among all iron-based superconductors. Large electron Fermi surfaces are observed around the zone corners, with an almost isotropic superconducting gap of ~10.3 meV, whereas there is no hole Fermi surface near the zone centre, which demonstrates that interband scattering or Fermi surface nesting is not a necessary ingredient for the unconventional superconductivity in iron-based superconductors. Thus, the sign change in the s(±) pairing symmetry driven by the interband scattering as suggested in many weak coupling theories becomes conceptually irrelevant in describing the superconducting state here. A more conventional s-wave pairing is probably a better description.

15.
Phys Rev Lett ; 109(3): 037003, 2012 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-22861887

RESUMO

We report a comprehensive angle-resolved photoemission spectroscopy study of the tridimensional electronic bands in the recently discovered Fe selenide superconductor ((Tl,Rb)(y)Fe(2-x)Se2 (T(c)=32 K). We determined the orbital characters and the k(z) dependence of the low energy electronic structure by tuning the polarization and the energy of the incident photons. We observed a small 3D electron Fermi surface pocket near the Brillouin zone center and a 2D like electron Fermi surface pocket near the zone boundary. The photon energy dependence, the polarization analysis and the local-density approximation calculations suggest a significant contribution from the Se 4p(z) and Fe 3d(xy) orbitals to the small electron pocket. We argue that the emergence of Se 4p(z) states might be the cause of the different magnetic properties between Fe chalcogenides and Fe pnictides.

16.
Nat Commun ; 13(1): 2975, 2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35624231

RESUMO

We report an unusual pressure-induced superconducting state that coexists with an antiferromagnetic ordering of Eu2+ moments and shows a large upper critical field comparable to the Pauli paramagnetic limit in EuTe2. In concomitant with the emergence of superconductivity with Tc ≈ 3-5 K above Pc ≈ 6 GPa, the antiferromagnetic transition temperature TN(P) experiences a quicker rise with the slope increased dramatically from dTN/dP = 0.85(14) K/GPa for P ≤ Pc to 3.7(2) K/GPa for P ≥ Pc. Moreover, the superconducting state can survive in the spin-flop state with a net ferromagnetic component of the Eu2+ sublattice under moderate magnetic fields µ0H ≥ 2 T. Our findings establish the pressurized EuTe2 as a rare magnetic superconductor possessing an intimated interplay between magnetism and superconductivity.

17.
Phys Rev Lett ; 107(6): 067001, 2011 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-21902359

RESUMO

We systematically investigated the in-plane resistivity anisotropy of electron-underdoped EuFe(2-x)Co(x)As(2) and BaFe(2-x)Co(x)As(2) and hole-underdoped Ba(1-x)K(x)Fe(2)As(2). Large in-plane resistivity anisotropy was found in the former samples, while tiny in-plane resistivity anisotropy was detected in the latter ones. When it is detected, the anisotropy starts above the structural transition temperature and increases smoothly through it. As the temperature is lowered further, the anisotropy takes a dramatic enhancement through the magnetic transition temperature. We found that the anisotropy is universally tied to the presence of T-linear behavior of resistivity. Our results demonstrate that the nematic state is caused by electronic degrees of freedom, and the microscopic orbital involvement in the magnetically ordered state must be fundamentally different between the hole- and electron-doped materials.

18.
Phys Rev Lett ; 105(11): 117003, 2010 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-20867600

RESUMO

The three-dimensional band structure and superconducting gap of Ba0.6K0.4Fe2As2 are studied with angle-resolved photoemission spectroscopy. In contrast with previous results, we have identified three holelike Fermi surface sheets near the zone center with sizable out-of-plane or kz dispersion. The superconducting gap on certain Fermi surface sheets shows significant kz dependence. Moreover, the superconducting gap sizes are different at the same Fermi momentum for two bands with different spatial symmetries (one odd, one even). Our results further reveal the three-dimensional and orbital-dependent structure of the superconducting gap in iron pnictides, which facilitates the understanding of momentum-integrated measurements and provides a distinct test for theories.

19.
Phys Rev Lett ; 105(11): 117002, 2010 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-20867599

RESUMO

The electronic structure of NaFeAs is studied with angle-resolved photoemission spectroscopy on high quality single crystals. Large portions of the band structure start to shift around the structural transition temperature and smoothly evolve as the temperature lowers through the spin density wave transition. Moreover, band folding due to magnetic order emerges slightly above the structural transition. Our observation provides direct evidence that the structural and magnetic transitions share the same origin and could both be driven by the electronic structure reconstruction in Fe-based superconductors instead of Fermi surface nesting. We did not observe any sign of a gap in the superconducting state, which is likely related to weakened superconductivity in the presence of the spin density wave.

20.
Eur Rev Med Pharmacol Sci ; 24(12): 6589-6596, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32633347

RESUMO

OBJECTIVE: The purpose of this study was to uncover the role of VASN in regulating proliferative ability of prostate cancer (PCa) cells through the yes-associated protein/transcriptional coactivator with PDZ-binding motif (YAP/TAZ) axis, thus influencing the progression of PCa. PATIENTS AND METHODS: VASN, YAP, and TAZ levels in PCa tissues or in the serum were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The diagnostic value of VASN in PCa was assessed by introducing receiver operating characteristic (ROC) curves. Besides, the regulatory effects of VASN on viability, clonality, and expression levels of YAP/TAZ were evaluated by cell counting kit-8 (CCK-8), colony formation, and Western blot, respectively. Finally, rescue experiments were conducted to uncover the involvement of YAP in VASN-regulated proliferation of PCa. RESULTS: Results manifested that VASN, YA, and TAZ were upregulated in PCa patients, and VASN presented a certain diagnostic value. Knockdown of VASN in LNCaP and C4-2 cells suppressed viability and clonality, and downregulated protein levels of YAP and TAZ. Notably, overexpression of YAP abolished the attenuated viability and clonality in PCa cells with VASN knockdown. CONCLUSIONS: VASN promotes proliferative ability in PCa via regulating the YAP/TAZ axis, thus aggravating the progression of the disease.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Proteínas de Transporte/biossíntese , Proliferação de Células/fisiologia , Proteínas de Membrana/biossíntese , Neoplasias da Próstata/metabolismo , Transativadores/biossíntese , Fatores de Transcrição/biossíntese , Linhagem Celular Tumoral , Humanos , Masculino , Neoplasias da Próstata/patologia , Proteínas com Motivo de Ligação a PDZ com Coativador Transcricional , Proteínas de Sinalização YAP
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