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1.
Eur Rev Med Pharmacol Sci ; 25(8): 3147, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33928594

RESUMO

Since this article has been suspected of research misconduct and the corresponding authors did not respond to our request to prove originality of data and figures, "MiR-101 affects proliferation and apoptosis of cervical cancer cells by inhibition of JAK2, by H. Wei, W.-R. He, K.-M. Chen, X.-W. Wang, C.-J. Yi, published in Eur Rev Med Pharmacol Sci 2019; 23 (13): 5640-5647-DOI: 10.26355/eurrev_201907_18299-PMID: 31298355" has been withdrawn. The Publisher apologizes for any inconvenience this may cause. https://www.europeanreview.org/article/18299.

2.
Phys Rev Lett ; 126(7): 076602, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33666464

RESUMO

As exemplified by the growing interest in the quantum anomalous Hall effect, the research on topology as an organizing principle of quantum matter is greatly enriched from the interplay with magnetism. In this vein, we present a combined electrical and thermoelectrical transport study on the magnetic Weyl semimetal EuCd_{2}As_{2}. Unconventional contribution to the anomalous Hall and anomalous Nernst effects were observed both above and below the magnetic transition temperature of EuCd_{2}As_{2}, indicating the existence of significant Berry curvature. EuCd_{2}As_{2} represents a rare case in which this unconventional transverse transport emerges both above and below the magnetic transition temperature in the same material. The transport properties evolve with temperature and field in the antiferromagnetic phase in a different manner than in the paramagnetic phase, suggesting different mechanisms to their origin. Our results indicate EuCd_{2}As_{2} is a fertile playground for investigating the interplay between magnetism and topology, and potentially a plethora of topologically nontrivial phases rooted in this interplay.

3.
Eur Rev Med Pharmacol Sci ; 24(7): 3555-3564, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32329829

RESUMO

OBJECTIVE: Finding a key target for the development of cervical cancer is conducive to the treatment of cervical cancer. LncRNA UCA1 plays a role in multiple tumors, such as the digestive tract and bladder. However, whether LncRNA UCA1 plays a role in cervical cancer is unclear. PATIENTS AND METHODS: The tumor tissues (tumor group) and adjacent tissues (normal group) of cervical cancer patients were collected for analysis of expression of LncRNA UCA1 and miR-145 by Real Time-Polymerase Chain Reaction (RT-PCR). Cervical cancer HeLa cell line was cultured and divided into NC group, si-UCA1 group, and si-UCA1+ miR-145 inhibitor group. It was followed by the analysis of LucRNA UCA1 expression by Real Time-PCR, cell proliferation by MTT assay, cell migration and invasion by respective cell scratch, transwell chamber assay, and targeted relationship between UCA1 and miR-145 by Dual-Luciferase activity. RESULTS: LncRNA UCA1 expression was significantly increased in cervical cancer and miR-145 expression was decreased compared with the normal group (p<0.05). There was a negative correlation between them (p<0.05). The downregulation of UCA1 significantly inhibited tumor cell proliferation, migration, and invasion compared with NC group (p<0.05). MiR-145 is the target miRNA of UCA1. The addition of miR-145 inhibitor reversed the effect of UCA1 siRNA on downregulating UCA1 expression, and the difference was statistically significant compared with the si-UCA1 group (p<0.05). CONCLUSIONS: LncRNA UCA1 expression is significantly increased in cervical cancer and miR-145 expression is decreased with a negative correlation between them. Lnc-RNA UCA1 regulates cervical cancer cell proliferation, migration, and invasion by targeting miR-145.


Assuntos
Movimento Celular , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , Idoso , Proliferação de Células , Feminino , Humanos , MicroRNAs/genética , Pessoa de Meia-Idade , RNA Longo não Codificante/genética
4.
Phys Rev Lett ; 123(4): 047001, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31491262

RESUMO

Although superconductivity in the vicinity of an antiferromagnetic (AFM) instability has been extensively explored in the last three decades or so, superconductivity in compounds with a background of ferromagnetic (FM) spin fluctuations is still rare. We report ^{75}As nuclear quadrupole resonance measurements on the A_{2}Cr_{3}As_{3} family, which is the first group of Cr-based superconductors at ambient pressure, with A being alkali elements. From the temperature dependence of the spin-lattice relaxation rate (1/T_{1}), we find that by changing A in the order of A=Na, Na_{0.75}K_{0.25}, K, and Rb, the system is tuned to approach a possible FM quantum critical point (QCP). This may be ascribed to the Cr2-As2-Cr2 bond angle that decreases towards 90°, which enhances the FM interaction via the Cr2-As2-Cr2 path. Upon moving away from the QCP, the superconducting transition temperature T_{sc} increases progressively up to 8.0 K in Na_{2}Cr_{3}As_{3}, which is in sharp contrast to the AFM case where T_{sc} usually shows a maximum around a QCP. The 1/T_{1} decreases rapidly below T_{sc} with no Hebel-Slichter peak, and ubiquitously follows a T^{5} variation below a characteristic temperature T^{*}≈0.6 T_{sc}, which indicates the existence of point nodes in the superconducting gap function commonly in the family. These results suggest that the A_{2}Cr_{3}As_{3} family is a possible solid-state analog of superfluid ^{3}He.

5.
Phys Rev Lett ; 123(4): 047201, 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31491259

RESUMO

The n-type HgCr_{2}Se_{4} exhibits a sharp semiconductor-to-metal transition (SMT) in resistivity accompanying the ferromagnetic order at T_{C}=106 K. Here, we investigate the effects of pressure and magnetic field on the concomitant SMT and ferromagnetic order by measuring resistivity, dc and ac magnetic susceptibility, as well as single-crystal neutron diffraction under various pressures up to 8 GPa and magnetic fields up to 8 T. Our results demonstrate that the ferromagnetic metallic ground state of n-type HgCr_{2}Se_{4} is destabilized and gradually replaced by an antiferromagnetic, most likely a spiral magnetic, and insulating ground state upon the application of high pressure. On the other hand, the application of external magnetic fields can restore the ferromagnetic metallic state again at high pressures, resulting in a colossal magnetoresistance (CMR) as high as ∼ 3×10^{11}% under 5 T and 2 K at 4 GPa. The present study demonstrates that n-type HgCr_{2}Se_{4} is located at a peculiar critical point where the balance of competition between ferromagnetic and antiferromagnetic interactions can be easily tipped by external stimuli, providing a new platform for achieving CMR in a single-valent system.

6.
Sci Adv ; 5(7): eaaw4718, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31309151

RESUMO

Weyl fermions as emergent quasiparticles can arise in Weyl semimetals (WSMs) in which the energy bands are nondegenerate, resulting from inversion or time-reversal symmetry breaking. Nevertheless, experimental evidence for magnetically induced WSMs is scarce. Here, using photoemission spectroscopy, we observe that the degeneracy of Bloch bands is already lifted in the paramagnetic phase of EuCd2As2. We attribute this effect to the itinerant electrons experiencing quasi-static and quasi-long-range ferromagnetic fluctuations. Moreover, the spin-nondegenerate band structure harbors a pair of ideal Weyl nodes near the Fermi level. Hence, we show that long-range magnetic order and the spontaneous breaking of time-reversal symmetry are not essential requirements for WSM states in centrosymmetric systems and that WSM states can emerge in a wider range of condensed matter systems than previously thought.

7.
Eur Rev Med Pharmacol Sci ; 23(13): 5640-5647, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31298355

RESUMO

OBJECTIVE: JAK2 expression and dysfunction play a role in tumor pathogenesis. Bioinformatics analysis revealed a targeted binding site between miR-101 and the 3'-UTR of JAK2 mRNA. This study investigated the role of miR-101 in regulating JAK2 expression and affecting the proliferation and apoptosis of cervical cancer cells. PATIENTS AND METHODS: The tumor tissues and adjacent tissues of patients with cervical cancer were collected. The expression of miR-101 and JAK2 was detected by qRT-PCR. The dual luciferase reporter gene assay validated the targeting relationship between miR-101 and JAK2. The cervical cancer Caski cells were cultured in vitro, and divided into miR-NC group and miR-101 mimic group. The expression of JAK2 and p-JAK2 was detected by Western blot, cell apoptosis was detected by flow cytometry, and cell proliferation was detected by EdU staining. RESULTS: Compared with adjacent tissues, miR-101 expression was significantly decreased, and JAK2 expression was increased in cervical cancer tissues. There was a targeted regulatory relationship between miR-101 and JAK2. Compared with HcerEpic cells, miR-101 expression in HeLa and Caski was significantly decreased, and the expression of JAK2 and p-JAK2 was significantly increased. Transfection of miR-101 mimic significantly reduced the expression of JAK2 and p-JAK2 in Caski cells, reduced cell proliferation and increased cell apoptosis. CONCLUSIONS: The decrease of miR-101 expression and the increase of JAK2 expression play a role in cervical cancer, while the increase of miR-101 expression can inhibit the proliferation and promote the apoptosis of cells by inhibiting the expression of JAK2.


Assuntos
Apoptose , Proliferação de Células , Janus Quinase 2/metabolismo , MicroRNAs/metabolismo , Neoplasias do Colo do Útero/patologia , Antagomirs/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Humanos , Janus Quinase 2/antagonistas & inibidores , Janus Quinase 2/genética , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Alinhamento de Sequência , Regulação para Cima , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo
8.
Sci Adv ; 5(5): eaau6459, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31058219

RESUMO

Topological semimetals are characterized by symmetry-protected band crossings, which can be preserved in different dimensions in momentum space, forming zero-dimensional nodal points, one-dimensional nodal lines, or even two-dimensional nodal surfaces. Materials harboring nodal points and nodal lines have been experimentally verified, whereas experimental evidence of nodal surfaces is still lacking. Here, using angle-resolved photoemission spectroscopy (ARPES), we reveal the coexistence of Dirac nodal surfaces and nodal lines in the bulk electronic structures of ZrSiS. As compared with previous ARPES studies on ZrSiS, we obtained pure bulk states, which enable us to extract unambiguously intrinsic information of the bulk nodal surfaces and nodal lines. Our results show that the nodal lines are the only feature near the Fermi level and constitute the whole Fermi surfaces. We not only prove that the low-energy quasiparticles in ZrSiS are contributed entirely by Dirac fermions but also experimentally realize the nodal surface in topological semimetals.

9.
Eur Rev Med Pharmacol Sci ; 22(19): 6280-6287, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30338793

RESUMO

OBJECTIVE: Cervical cancer is frequent in females. Epidermal growth factor receptor has a prominent expression in certain malignant tumors. This study aims to observe the expressional profile of epidermal growth factor receptor (EGFR) in cervical cancer patients, and mutation of EGFR gene related with its sensitivity towards tyrosine kinase inhibitor. MATERIALS AND METHODS: Cervical cancer patients from our hospital were recruited as the experimental group, in parallel with chronic cervicitis patients as control group. Serum EGFR level was measured by enzyme-linked immunosorbent assay (ELISA), and EGFR levels in cervical tissues were quantified by immunohistochemistry assay (IHC) staining. Real Time-PCR (RT-PCR) examined mutations of exon 18, 19, and 21 of the EGFR gene, to analyze their correlation with clinical or pathological features. RESULTS: Serum EGFR in experimental group was 1.16 ± 0.04 ng/ml, significantly higher than control group (p < 0.05). EGFR positive rate was 71.1% in cancer tissues, significantly higher compared to controlled or adjacent tissues (p < 0.05). Mutation rats of EGFR exon 19 and exon 21 were 3.3% and 5%, respectively. No mutation was found in exon 18. Such mutations of EGFR gene were related with cancer differentiation grade, tumor-lymph-node-metastasis (TNM) stage, lymph node or distal metastasis (p < 0.05), but not age, Karnofsky performance score (KPS) score or infiltration depth. CONCLUSIONS: EGFR is highly expressed in serum and tumors of cervical cancer patients, some of which showed mutations of exon 19 and 21 of EGFR gene with relatively lower frequency. Mutation rates were significantly higher in patients with highly differentiated grade, early TNM stage, and those without lymph node or distal metastasis.


Assuntos
Mutação , Neoplasias do Colo do Útero/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Receptores ErbB/sangue , Receptores ErbB/genética , Éxons , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Inibidores de Proteínas Quinases/uso terapêutico , Regulação para Cima , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética
10.
J Phys Condens Matter ; 29(45): 455603, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-29049031

RESUMO

K2Cr3As3 is a newly discovered quasi-1D superconductor with a T c = 6.1 K and an upper critical field µ 0 H c2(0) ≈ 40 T three times larger than the Pauli paramagnetic limit µ 0 H p that is suggestive of a spin-triplet Cooper pairing. In this paper, we have investigated the effects of hydrostatic pressure on its T c and µ 0 H c2 by measuring the ac magnetic susceptibility χ'(T) under magnetic fields at various hydrostatic pressures up to 7.5 GPa. The major findings include: (1) T c is suppressed gradually to below 2 K at 7.5 GPa; (2) the estimated µ 0 H c2(0) decreases dramatically to below µ 0 H p above ~2 GPa and becomes slight lower than the orbital limiting field [Formula: see text] estimated from the initial slope of upper critical field via [Formula: see text] = -0.73T cdH c2/[Formula: see text] in the clean limit; (3) the estimated Maki parameter α = √2[Formula: see text]/H p drops from 4 at ambient pressure to well below 1 at P > 2 GPa, suggesting the crossover from Pauli paramagnetic limiting to orbital limiting in the pair breaking process upon increasing pressure. These observations suggested that the application of hydrostatic pressure could drive K2Cr3As3 away from the ferromagnetic instability and lead to a breakdown of the spin-triplet pairing channel. We have also made a side-by-side comparison and discussed the distinct effects of chemical and physical pressures on the superconducting properties of K2Cr3As3.

11.
Radiother Oncol ; 41(2): 163-7, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9004360

RESUMO

BACKGROUND AND PURPOSE: Ginkgo biloba leaf extract (GBE) is known to increase peripheral blood circulation. The hypothesis that GBE may be able to enhance radiosensitivity of tumor by improving tumor blood flow and thus decreasing hypoxic fraction was tested. MATERIALS AND METHODS: Fibrosarcoma (FSaII) growing in C3H mouse leg muscle was used as a tumor model. GBE was given i.p. 1 h before irradiation with or without priming dose given 1 day earlier. Effect on tumor and normal tissue radiation reaction was investigated. RESULTS: Tumor growth delay by radiation was more elongated after two doses (1-day interval) of GBE than after a single dose. Radiation dose for 3-day tumor growth delay was decreased from 12.45 (10.97-13.93) Gy to 6.06 (3.89-8.22) Gy by two doses of GBE [enhancement ratio = 2.06 (1.32-2.79)]. Hypoxic cell fraction was 10.6% (6.3-18.2%) for control, 7.2% (3.8-14.0%) after a single dose (P = 0.18) and 2.7% (1.5-5.0%) after two doses (P < 0.001). Radiation effect on normal tissue, estimated by acute skin reaction and jejunal crypt assay, was not affected by GBE. CONCLUSION: Ginkgo biloba extract enhances radiation effect on tumor without increasing acute normal tissue radiation damage in this model system probably by increasing tumor blood flow and further investigation for this possible radiosensitizer is needed.


Assuntos
Fibrossarcoma/radioterapia , Neoplasias Musculares/radioterapia , Extratos Vegetais/uso terapêutico , Radiossensibilizantes/uso terapêutico , Animais , Hipóxia Celular , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C3H , Transplante de Neoplasias , Doses de Radiação
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