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1.
Artigo em Chinês | MEDLINE | ID: mdl-38664029

RESUMO

Objective: To explore the effects of early debridement and conservative eschar removal followed by wound coverage with acellular dermal matrix (ADM), i.e., early surgery, in the treatment of children with deep burns. Methods: This study was a retrospective cohort study. From January 2017 to December 2022, 278 deep burned hospitalized children aged 1-7 years who met the inclusion criteria were admitted to Central Hospital Affiliated to Shandong First Medical University. According to the differences in treatment processes, 134 children who underwent early surgery+routine dressing change were enrolled in eschar removal+dressing change group (77 males and 57 females, aged 1 (1, 2) years), and 144 children who underwent only routine dressing change were enrolled in dressing change alone group (90 males and 54 females, aged 1 (1, 2) years). Fifty-one children without full-thickness burns in eschar removal+dressing change group were enrolled in eschar removal+dressing change group 1 (26 males and 25 females, aged 1 (1, 2) years), and 57 cases of the 83 children with full-thickness burns who did not undergo autologous skin grafting at the same time of early surgery (namely early skin grafting) in eschar removal+dressing change group were included in eschar removal+dressing change group 2 (37 males and 20 females, aged 1 (1, 2) years). Seventy-six children without full-thickness burns in dressing change alone group were included in dressing change alone group 1 (51 males and 25 females, aged 1 (1, 3) years), and 68 children with full-thickness burns in dressing change alone group were included in dressing change alone group 2 (39 males and 29 females, aged 1 (1, 2) years). For deep partial-thickness burn wounds and small full-thickness burn wounds in eschar removal+dressing change group, the eschar removal was performed on the basis of retaining a thin layer of denatured dermis so as to preserve the healthy tissue of the wound base, and ADM was applied to all wounds externally after eschar removal. For larger full-thickness burn wounds in this group, especially those located in the functional part of joints, eschar removal to the plane layer of viable tissue and early autologous skin grafting was needed. When the superficial wounds of children healed or tended to heal, the residual wounds were evaluated, and elective autologous skin grafting was performed if it was difficult to heal within 14 days. The healing time, intervention healing time, times of operation/dressing change, and times of intervention operation/dressing change in children with deep partial-thickness burn wounds of children in eschar removal+dressing change group, dressing change alone group, eschar removal+dressing change group 1, and dressing change alone group 1 were recorded. At the last follow-up (follow-up period was set to 7-12 months), the modified Vancouver scar scale (mVSS) scores of the most severe area of scar hyperplasia of healed deep partial-thickness burn wounds of 54 children in eschar removal+dressing change group and 48 children in dressing change alone group were recorded. The healing time and times of operation/dressing change of all burn wounds of children in eschar removal+dressing change group and dressing change alone group, and the healing time and times of operation/dressing change of full-thickness burn wounds of children in eschar removal+dressing change group 2 and dressing change alone group 2 were recorded. The incidences of wound infection, sepsis, fever, and fever after 5 days of burns in children of eschar removal+dressing change group and dressing change alone group during wound healing. Results: Compared with those in dressing change alone group, the healing time and intervention healing time were significantly shortened, and the times of operation/dressing change and times of intervention operation/dressing change were significantly reduced in children with deep partial-thickness burn wounds in eschar removal+dressing change group (with Z values of -11.00, -11.33, -12.64, and -11.65, respectively, P<0.05). Compared with those in dressing change alone group 1, the healing time and intervention healing time were significantly shortened, and the times of operation/dressing change and times of intervention operation/dressing change were significantly reduced in children with deep partial-thickness burn wounds in eschar removal+dressing change group 1 (with Z values of 6.57, 6.46, 8.04, and 6.57, respectively, P<0.05). At the last follow-up, the mVSS score of the most severe scar hyperplasia area of healed deep partial-thickness burn wounds of 54 children in eschar removal+dressing change group was 4.00 (3.00,5.00), which was significantly lower than 6.50 (5.00,7.00) of 48 children in dressing change alone group (Z =-4.67, P<0.05).Compared with those in dressing change alone group, the healing time was significantly shortened, and times of operation/dressing change was significantly reduced in all burn wounds in eschar removal+dressing change group (with Z values of -5.20 and -6.34, respectively, P<0.05). Compared with those in dressing change alone group 2, the healing time was significantly shortened, and times of operation/dressing change was significantly reduced in full-thickness burn wounds in eschar removal+dressing change group 2 (with Z values of -5.22 and -5.73, respectively, P<0.05). During wound healing, the probabilities of fever and fever after 5 days of burns in children of eschar removal+dressing change group were significantly lower than those in dressing change alone group (with χ2 values of 4.13 and 3.91, respectively, P<0.05); only 1 child in dressing change alone group developed sepsis, and there was no statistically significant difference in the wound infection rate of children in the two groups (P>0.05). Conclusions: For children with deep burns, early surgery, and early skin grafting or elective autologous skin grafting as needed, have better short-term and long-term effects than those without early surgery.


Assuntos
Derme Acelular , Queimaduras , Desbridamento , Transplante de Pele , Humanos , Masculino , Queimaduras/terapia , Queimaduras/cirurgia , Feminino , Estudos Retrospectivos , Lactente , Pré-Escolar , Transplante de Pele/métodos , Desbridamento/métodos , Criança , Cicatrização
2.
Artigo em Chinês | MEDLINE | ID: mdl-37805721

RESUMO

Objective: To investigate the application effects of nitrous oxide and oxygen mixed inhalation technology on analgesia and sedation during debridement and dressing change in children with moderate or severe burns. Methods: A retrospective non-randomized contemporary controlled study was conducted. From December 2019 to November 2021, 140 burn children with moderate or severe burns, aged 1 to 3 years, who met the inclusion criteria were admitted to Central Hospital Affiliated to Shandong First Medical University. During debridement and dressing change 3 to 14 days after injury, 42 children, including 23 males and 19 females, who received nurse-centered pain management mode and analgesia and sedation with nitrous oxide and oxygen mixed inhalation technology were included in nitrous oxide group (the dressing change process using the above-mentioned technology for the first time was selected for the follow-up study). Another 42 children, including 24 males and 18 females, were included in non-nitrous oxide group from 98 children who did not apply analgesia or sedation treatment during dressing change with stratified random sampling (one dressing change process was randomly selected for the follow-up study). The face, legs, activity, cry, and consolability scale and Ramsay sedation scale were used to evaluate the pain intensity and degree of sedation, respectively, at 30 minutes before dressing change (hereinafter referred to as before dressing change), immediately after debridement, and at 30 minutes after finishing dressing change (hereinafter referred to as after dressing change). After dressing change, the self-made satisfaction scale was used to evaluate the satisfaction degree of dressing change surgeons and guardians of children for analgesic effects during dressing change. The duration of dressing change and the healing time of deep partial-thickness burn wounds were recorded. The heart rate and percutaneous arterial oxygen saturation (SpO2) before, during, and after dressing change and the occurrence of adverse events such as nausea and vomiting during dressing change were recorded. Data were statistically analyzed with Mann-Whitney U test, chi-square test, analysis of variance for repeated measurement, independent sample t test, and Bonferroni correction. Results: There were no significant differences in the score of pain intensity and score of sedation degree between children in two groups before and after dressing change (P>0.05). Immediately after debridement, the score of pain intensity of children in nitrous oxide group was 2.5±0.7, which was significantly lower than 7.6±1.0 in non-nitrous oxide group (t=-26.69, P<0.05); the score of sedation degree of children in nitrous oxide group was 1.83±0.38, which was significantly higher than 1.21±0.42 in non-nitrous oxide group (t=7.15, P<0.05). After dressing change, the satisfaction degree scores of dressing change surgeons and guardians of children for analgesic effects during dressing change of children in nitrous oxide group were significantly higher than those in non-nitrous oxide group (with t values of 10.53 and 2.24, respectively, P<0.05). The dressing change duration of children in nitrous oxide group was significantly shorter than that in non-nitrous oxide group (t=-5.33, P<0.05). The healing time of deep partial-thickness burn wounds in children between the two groups had no significant difference (P>0.05). The heart rate of children in nitrous oxide group was significantly lower than that in non-nitrous oxide group during dressing change (t=-12.40, P<0.05), while the SpO2 was significantly higher than that in non-nitrous oxide group (t=5.98, P<0.05). During dressing change, 2 children had nausea and 1 child had euphoria in nitrous oxide group, while heart rate of all children in non-nitrous oxide group continued to be higher than the normal range. Conclusions: In the process of debridement and dressing change in children with moderate or severe burns, the use of nurse-centered pain management mode and the standardized use of nitrous oxide and oxygen mixed inhalation technology can safely and effectively control pain and sedation.


Assuntos
Analgesia , Queimaduras , Masculino , Feminino , Humanos , Criança , Óxido Nitroso/uso terapêutico , Manejo da Dor , Desbridamento , Oxigênio , Seguimentos , Estudos Retrospectivos , Resultado do Tratamento , Queimaduras/cirurgia , Dor , Náusea , Infecção da Ferida Cirúrgica , Bandagens , Analgésicos
3.
Niger J Clin Pract ; 26(4): 524-527, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37203120

RESUMO

Nephronophthisis (NPHP) is a common pediatric cystic kidney disease, accounting for approximately 10% of end-stage renal failure cases in children. NPHP is primarily diagnosed through the identification of indel mutations and copy number variants (CNVs), and patients carrying NPHP1 mutations usually progress to renal failure at a mean age of 13 years old. However, the association between CNVs containing NPHP1 variations and the progression of NPHP-induced disease remains unclear. Here, we report three NPHP patients in a family. The proband had developed stage 4 chronic kidney disease (CKD) at 9 years old, and her younger brother and older sister had developed renal failure at 8 and 10 years old, respectively. A genetic diagnosis showed that they carried two rare CNVs, including homozygous loss of NPHP1, MALL, ACTR1AP1, MTLN, and LOC100507334. Heterozygous deletions mainly consisted of non-coding RNA genes on both sides of the CNVs. The proband was in stage 4 of CKD while her brother had progressed to renal failure, probably due to more extensive heterozygous deletion of a 67.115 kbp fragment, which included LIMS3-LOC440895, LOC440895, GPAA1P1, ZBTB45P1, and LINC0112 genes. This report demonstrates that larger CNV deletions, including homozygous NPHP1, MALL, and MTLN mutations and heterozygous deletions, presumably accelerate disease progression. Therefore, early genetic diagnosis plays a crucial role in the intervention and prognosis of these patients.


Assuntos
Falência Renal Crônica , Insuficiência Renal Crônica , Humanos , Masculino , Criança , Feminino , Adolescente , Variações do Número de Cópias de DNA , Deleção de Sequência , Proteínas do Citoesqueleto/genética , Proteínas de Membrana/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Falência Renal Crônica/genética , Insuficiência Renal Crônica/genética
4.
Nat Commun ; 13(1): 6560, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36323685

RESUMO

The interactions between electrons and antiferromagnetic magnons (AFMMs) are important for a large class of correlated materials. For example, they are the most plausible pairing glues in high-temperature superconductors, such as cuprates and iron-based superconductors. However, unlike electron-phonon interactions (EPIs), clear-cut observations regarding how electron-AFMM interactions (EAIs) affect the band structure are still lacking. Consequently, critical information on the EAIs, such as its strength and doping dependence, remains elusive. Here we directly observe that EAIs induce a kink structure in the band dispersion of Ba1-xKxMn2As2, and subsequently unveil several key characteristics of EAIs. We found that the coupling constant of EAIs can be as large as 5.4, and it shows strong doping dependence and temperature dependence, all in stark contrast to the behaviors of EPIs. The colossal renormalization of electron bands by EAIs enhances the density of states at Fermi energy, which is likely driving the emergent ferromagnetic state in Ba1-xKxMn2As2 through a Stoner-like mechanism with mixed itinerant-local character. Our results expand the current knowledge of EAIs, which may facilitate the further understanding of many correlated materials where EAIs play a critical role.

5.
Zhonghua Gan Zang Bing Za Zhi ; 30(6): 637-643, 2022 Jun 20.
Artigo em Chinês | MEDLINE | ID: mdl-36038326

RESUMO

Objective: The investigation and research on the application status of Hepatic Venous Pressure Gradient (HVPG) is very important to understand the real situation and future development of this technology in China. Methods: This study comprehensively investigated the basic situation of HVPG technology in China, including hospital distribution, hospital level, annual number of cases, catheters used, average cost, indications and existing problems. Results: According to the survey, there were 70 hospitals in China carrying out HVPG technology in 2021, distributed in 28 provinces (autonomous regions and municipalities directly under the central Government). A total of 4 398 cases of HVPG were performed in all the surveyed hospitals in 2021, of which 2 291 cases (52.1%) were tested by HVPG alone. The average cost of HVPG detection was (5 617.2±2 079.4) yuan. 96.3% of the teams completed HVPG detection with balloon method, and most of the teams used thrombectomy balloon catheter (80.3%). Conclusion: Through this investigation, the status of domestic clinical application of HVPG has been clarified, and it has been confirmed that many domestic medical institutions have mastered this technology, but it still needs to continue to promote and popularize HVPG technology in the future.


Assuntos
Hipertensão Portal , China/epidemiologia , Veias Hepáticas , Humanos , Hipertensão Portal/diagnóstico , Cirrose Hepática , Pressão na Veia Porta
6.
Zhonghua Yi Xue Za Zhi ; 102(4): 273-278, 2022 Jan 25.
Artigo em Chinês | MEDLINE | ID: mdl-35073676

RESUMO

Objective: To evaluate the clinical value of aspirin as a prophylactic for transplant renal artery stenosis (TRAS). Methods: From January 2017 to November 2019, clinical data of 307 patients who had undergone renal transplant in Zhengzhou University People's Hospital were collected. Patients were divided into two groups: the treatment group (124 recipients who had taken oral aspirin 100 mg/d after transplant) and the control group (183 recipients who had not taken aspirin after transplant). The general data, incidence of initially diagnosed and confirmed TRAS, type of renal artery anastomosis vessels, duration of stenosis, location of stenosis, and complications were compared between the two groups. The treatment group was further divided into two subgroups, the early group (92 recipients) and the delayed group (32 recipients), according to the time of starting aspirin after operation. Subgroup analysis was performed. Results: Among all 307 patients included, there were 241 males and 66 females, aged 19-64 years. There were no statistical difference between the treatment and control groups in terms of gender, age, comorbidities, number of arterial vessels, type of graft, and acute rejection all P>0.05. Among 46 initially diagnosed TRAS patients, 13 (10.5%) and 33 (18.0%) cases were in the treatment and control group respectively, with no statistically significant difference in stenosis rate (P>0.05). The number of confirmed TRAS patients was 1 (0.8%) and 24 (13.1%) in the treatment and control group respectively, with statistically significant difference in stenosis rate (P<0.001). The proportion of patients with bleeding disorders in the treatment group was slightly higher than that in the control group (13.7% vs 8.7%), and the proportion of infarct diseases was slightly lower than that in the control group (1.6% vs 4.9%). But there was no significant difference in aspirin-related complications between the two groups (P>0.05). Subgroup analysis showed that there was no significant difference in initially diagnosed and confirmed TRAS and aspirin-related complications between the early group and the delayed group (all P>0.05). Conclusions: Oral low-dose aspirin after kidney transplantation can effectively reduce the incidence of TRAS, without increasing the risk of aspirin-related complications.


Assuntos
Transplante de Rim , Obstrução da Artéria Renal , Aspirina , Constrição Patológica , Feminino , Humanos , Incidência , Masculino
7.
Zhonghua Zhong Liu Za Zhi ; 43(7): 769-774, 2021 Jul 23.
Artigo em Chinês | MEDLINE | ID: mdl-34289571

RESUMO

Objective: To investigate the effect of long non-coding RNA HOTAIR (LncRNA HOTAIR) on the proliferation, apoptosis and drug resistance of Wilms tumor cells and its molecular mechanism. Methods: Collected nephroblastoma tissues and normal tumor side tissues in 32 children with renal syblastoma surgical treatment at Zhengzhou University Children's Hospital from 2015 to 2019. Real-time quantitative reverse transcription polymerase chain reaction, (qRT-PCR)was used to detect the expression of HOTAIR in Wilms tumor tissues and adjacent tissues. Small interfering RNA technology was used to delete the expression of HOTAIR in Wilms tumor cell SK-NEP-1. Cell counting kit-8 (CCK-8)was used to detect cell proliferation after transfection. Flow cytometry and terminal deoxynucleotidyl transferase mediated dUTP nick-end labeling (TUNEL) staining to detect the apoptosis. Western blot was used to detect the expression of Wnt/ß-catenin signaling pathway related proteins.CCK-8 was used to detect the proliferation inhibition of cells treated with different concentrations of cisplatin after transfection. Results: Compared with adjacent tissues, HOTAIR was highly expressed in Wilms tumor tissues (P<0.05). The expression levels of Wnt, ß-catenin, Cyclin D1, c-myc in the control group were (0.89±0.08), (0.94±0.10), (0.72±0.06), (1.10±0.11), and (1.06±0.11), (0.92±0.08), (0.66±0.07), (1.25±0.11) of the si-RNA group, while (0.54±0.05), (0.41±0.05), (0.25±0.03), (0.56±0.06) of the si-HOTAIR group. The expression levels of these protein were significantly down-regulated in the si-HOTAIR group when compared with the control group and the si-RNA group (P<0.05). The absorbance (A) values of SK-NEP-1 cells in the si-HOTAIR group at 24, 48 and 72 hours after transfection were (0.31±0.02), (0.37±0.04), (0.69±0.07), significantly lower than (0.49±0.05), (0.78±0.08), (1.22±0.14) in the control group and (0.57±0.06), (0.68±0.07), (0.94±0.09) in the si-RNA group (P<0.05). The apoptosis rate in the si-HOTAIR group was (13.81±1.25)%, significantly higher than (6.54±0.72)% in the control group and (4.35±0.40)% in the si-RNA group (P<0.05). The cell positive rate of TUNEL cells in the si-HOTAIR group was (35.14±3.50)%, significantly higher than (20.16±2.18)% in the control group and (21.09±2.35)% in the si-RNA group (P<0.05). The median inhibitory concentration (IC(50)) of the si-HOTAIR group was (62.48±5.97) µmol/L, significantly lower than (88.27±9.05) µmol/L of the control group and (92.50±9.11) µmol/L of the si-RNA group (P<0.05). Conclusions: Suppression of LncRNA HOTAIR can inhibit the proliferation of Wilms tumor cells, promote cell apoptosis, decrease cell resistance to cisplatin. The mechanism may be related to the inhibition of Wnt/ß-catenin signaling pathway activation.


Assuntos
Neoplasias Renais , RNA Longo não Codificante , Tumor de Wilms , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Criança , Resistência a Medicamentos , Humanos , Neoplasias Renais/genética , RNA Longo não Codificante/genética , Tumor de Wilms/genética , Via de Sinalização Wnt , beta Catenina/genética , beta Catenina/metabolismo
8.
J Phys Condens Matter ; 33(32)2021 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-33232949

RESUMO

It was generally believed that weak van der Waals interactions exist between neighboring layers in the two-dimensional group-IV chalcogenides. Using PbSe as a prototypal example, we find additional strong coupling between the Pb-Pb layers, as evidenced by detailed analysis of the differential charge density plot. The coupling is covalent-like and can be fine-tuned to obviously reduce the phonon thermal conductivity but slightly change the electronic transport of PbSe layer. As a consequence, a maximumZTvalue of 2.5 can be realized at 900 K for thep-type system. Our work also offers an effective and feasible design strategy to enhance the thermoelectric performance of similar layered structures.

9.
J Phys Condens Matter ; 32(43): 435603, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32756017

RESUMO

We report inelastic neutron scattering (INS) investigations on the bilayer Fe-based superconductor CsCa2Fe4As4F2 above and below its superconducting transition temperature T c ≈ 28.9 K to investigate the presence of a neutron spin resonance. This compound crystallises in a body-centred tetragonal lattice containing asymmetric double layers of Fe2As2 separated by insulating CaF2 layers and is known to be highly anisotropic. Our INS study clearly reveals the presence of a neutron spin resonance that exhibits higher intensity at lower momentum transfer (Q) at 5 K compared to 54 K, at an energy of 15 meV. The energy E R of the observed spin resonance is broadly consistent with the relationship E R = 4.9k B T c, but is slightly enhanced compared to the values observed in other Fe-based superconductors. We discuss the nature of the electron pairing symmetry by comparing the value of E R with that deduced from the total superconducting gap value integrated over the Fermi surface.

11.
J Phys Condens Matter ; 31(38): 385701, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31174197

RESUMO

The electronic and phonon transport properties of graphene-like boron phosphide (BP), boron arsenide (BAs), and boron antimonide (BSb) monolayers are investigated using first-principles calculations combined with the Boltzmann theory. By considering both the phonon-phonon and electron-phonon scatterings, we demonstrate that the strong bond anharmonicity in the BAs and BSb monolayers can dramatically suppress the phonon relaxation time but hardly affect that of electron. As a consequence, both systems exhibit comparable power factors with that of the BP monolayer but much lower lattice thermal conductivities. Accordingly, a maximum ZT value above 3.0 can be realized in both BAs and BSb monolayers at optimized carrier concentration. Interestingly, very similar p - and n-type thermoelectric performance is observed in the BSb monolayer along the zigzag direction, which is of vital importance in the fabrication of thermoelectric modules with comparable efficiencies.

12.
Clin Transl Oncol ; 21(2): 167-177, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30003530

RESUMO

PURPOSE: To assess the efficacy and safety of drug-eluting beads transarterial chemoembolization (DEB-TACE) in liver cancer patients with different times of previous conventional transarterial chemoembolization (cTACE) treatments. METHODS: 367 liver cancer patients about to receive DEB-TACE treatment were enrolled in this prospective cohort study. All patients were divided into no previous cTACE group (NPC group), 1-2 times previous cTACE group (PC group) and triple or above previous cTACE group (TPC group) according to the times of previous cTACE treatments. RESULTS: There was no difference in complete response (CR) (P = 0.671) and objective response rate (ORR) (P = 0.062) among three groups. Additionally, no difference in overall survival (OS) among groups (P = 0.899) was found. As to liver function, most liver function indexes were deteriorative at 1 week after DEB-TACE operation, but returned to baseline at 1-3 months after DEB-TACE operation in all three groups, while percentage of abnormal total bile acid (TBA) patients was higher in TPC group than NPC and PC groups at 1-3 month post-DEB-TACE (P = 0.018). As for safety profiles, the incidence of pain during DEB-TACE operation was lower in TPC group compared to NPC and PC groups (P = 0.005), while no difference of other adverse events was found during and 1 month post-DEB-TACE treatment among three groups. CONCLUSION: DEB-TACE treatment was equally efficient and tolerated in liver cancer patients with different times of previous cTACE treatments.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Quimioembolização Terapêutica/métodos , Doxorrubicina/administração & dosagem , Neoplasias Hepáticas/terapia , Adulto , Idoso , Quimioembolização Terapêutica/mortalidade , Portadores de Fármacos , Feminino , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Masculino , Microesferas , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/terapia , Resultado do Tratamento
13.
J Phys Condens Matter ; 31(4): 044001, 2019 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-30543523

RESUMO

RbGd2Fe4As4O2 is a newly discovered self-hole-doped stoichiometric superconductor, which has a hybrid structure with separated double FeAs layers and exhibits a high superconducting transition temperature T c = 35 K. Here, we report the effect of pressure (P) on its T c and normal-state transport properties by measuring the temperature dependence of resistivity ρ(T) under various pressures up to 14 GPa with a cubic anvil cell apparatus. We found that the T c is suppressed monotonically to ca. 12.5 K upon increasing pressure to 14 GPa with a slope change of T c(P) at around 4 GPa. In addition, the low-temperature normal-state ρ(T), which is proportional to T n , also evolves gradually from a non-Fermi-liquid with n = 1 at ambient pressure to a Fermi liquid with n = 2 at P ⩾ 4 GPa. Accompanying with the non-Fermi-liquid to Fermi-liquid crossover, the quadratic temperature coefficient of resistivity, which reflects the effective mass of charge carriers, also experiences a significant reduction as commonly observed in the vicinity of a magnetic quantum critical point (QCP). Our results indicate that the stoichiometric RbGd2Fe4As4O2 at ambient pressure might be located near a QCP such that the enhanced critical spin fluctuations lead to high-T c superconductivity. The application of pressure should broaden the electronic bandwidth and weaken the spin fluctuations, and then restore a Fermi-liquid ground state with lower T c.

14.
Nat Commun ; 8(1): 156, 2017 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-28761126

RESUMO

Unlike the widely studied ReFeAsO series, the newly discovered iron-based superconductor ThFeAsN exhibits a remarkably high critical temperature of 30 K, without chemical doping or external pressure. Here we investigate in detail its magnetic and superconducting properties via muon-spin rotation/relaxation and nuclear magnetic resonance techniques and show that ThFeAsN exhibits strong magnetic fluctuations, suppressed below ~35 K, but no magnetic order. This contrasts strongly with the ReFeAsO series, where stoichiometric parent materials order antiferromagnetically and superconductivity appears only upon doping. The ThFeAsN case indicates that Fermi-surface modifications due to structural distortions and correlation effects are as important as doping in inducing superconductivity. The direct competition between antiferromagnetism and superconductivity, which in ThFeAsN (as in LiFeAs) occurs at already zero doping, may indicate a significant deviation of the s-wave superconducting gap in this compound from the standard s ± scenario.Exploring the interplay between the superconducting gap and the antiferromagnetic phase in Fe-based superconductors remains an open issue. Here, the authors show that Fermi-surface modifications by means of structural distortions and correlation effects are as important as doping in inducing superconductivity in undoped ThFeAsN.

15.
Eur Rev Med Pharmacol Sci ; 20(18): 3825-3829, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27735035

RESUMO

OBJECTIVE: The present study aimed to clarify the expression pattern and prognostic role of miR-409-3p in breast cancer patients. MATERIALS AND METHODS: miR-409-3p levels in breast cancer tissues were tested by qRT-PCR. The chi-square test and Fishers exact tests were used to examine the associations between miR-409-3p expression and the clinicopathological characters. Overall survival (OS) was estimated using the Kaplan-Meier method. The univariable and the multivariable Cox regression analyses were used to evaluate independent prognostic factors. RESULTS: miR-409-3p expression in breast cancer specimens was observed to be decreased compared with matched normal breast tissues (p < 0.01). Additionally, low miR-409-3p expression in breast cancer tissues was significantly associated with the advanced TNM stage (p = 0.004), lymph node metastasis (p = 0.001), and poorer pathological differentiation (p = 0.026). The patients in the low miR-409-3p group had a shorter overall survival than those in the high miR-409-3p group (p < 0.001). Furthermore, the univariate and the multivariate analyses showed that miR-409-3p expression was an independent predictor of overall survival (p < 0.05). CONCLUSIONS: Our results revealed that miR-409-3p was related to the prognosis of patients with breast cancer and might be a promising predictor of miR-409-3p recurrence.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Feminino , Humanos , Estimativa de Kaplan-Meier , MicroRNAs/genética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Prognóstico
16.
Eur Rev Med Pharmacol Sci ; 20(11): 2230-4, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27338046

RESUMO

OBJECTIVE: The aim of this study was to investigate the expression of LncRNA HMlincRNA717 in human pancreatic cancer and its correlation with clinicopathological features PATIENTS AND METHODS: Using reverse transcription quantitative polymerase chain reaction, HMlincRNA717 expression was detected in primary pancreatic cancer tissues. The correlation of HMlincRNA717 with clinicopathological features and prognosis were also analyzed. Survival analysis was performed using the Kaplan-Meier method and Cox's proportional hazards model. RESULTS: The expression of HMlincRNA717 was significantly decreased in pancreatic cancer tissues compared with paired adjacent normal tissues (p < 0.01). It was also proved that HMlincRNA717 expression was to be associated with clinical stage (p = 0.001), tumor size (p < 0.001), lymph node metastasis (p = 0.003), and distant metastasis (p < 0.001) in pancreatic cancer patients. Significantly shorter 5-year overall survival (OS) were observed in patients with lower expression of the HMlincRNA717 (p < 0.01). Multivariate analysis showed that decreased HMlincRNA717 expression was a poor independent prognostic factor for pancreatic cancer patients. CONCLUSIONS: Our findings showed that the expression of lncRNA HMlincRNA717 was down-regulated in pancreatic cancer and associated with overall survival, suggesting that HMlincRNA717 could be a potential prognostic biomarker for pancreatic cancer progression.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Pancreáticas/patologia , RNA Longo não Codificante/genética , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Reação em Cadeia da Polimerase em Tempo Real
17.
Phys Rev Lett ; 115(14): 147002, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26551818

RESUMO

We report (75)As nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) studies on the superconductor Rb(2)Cr(3)As(3) with a quasi-one-dimensional crystal structure. Below T∼100 K, the spin-lattice relaxation rate (1/T(1)) divided by temperature, 1/T(1)T, increases upon cooling down to T(c)=4.8 K, showing a Curie-Weiss-like temperature dependence. The Knight shift also increases with decreasing temperature. These results suggest ferromagnetic spin fluctuation. In the superconducting state, 1/T(1) decreases rapidly below T(c) without a Hebel-Slichter peak, and follows a T(5) variation below T∼3 K, which points to unconventional superconductivity with point nodes in the gap function.

18.
J Phys Condens Matter ; 27(49): 495701, 2015 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-26595404

RESUMO

We have performed polarized Raman scattering measurements on the newly discovered superconductor Ta4Pd3Te16 (T(c) = 4.6 K). We observe 28 out of 33 Raman active modes, with frequencies in good accordance with first-principles calculations. Although most of the phonons observed vary only slightly with temperature and do not exhibit any asymmetric profile that would suggest strong electron-phonon coupling, the linewidth of the A(g) phonon mode at 89.9 cm(-1) shows an unconventional increase with temperature decreasing, which is possibly due to a charge-density-wave transition or the emergence of charge-density-wave fluctuations below a temperature estimated to fall in the 140-200 K range.

19.
J Phys Condens Matter ; 26(26): 265701, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24912631

RESUMO

Eu(Fe(0.79)Ru(0.21))2As2 is suggested to be a nodeless superconductor based on the empirical correlation between pnictogen height (hPn) and superconducting gap behavior, in contrast to BaFe2(As(0.7)P(0.3))2 and Ba(Fe(0.65)Ru(0.35))2As2. We studied the low-lying electronic structure of Eu(Fe(0.79)Ru(0.21))2As2 with angle-resolved photoemission spectroscopy (ARPES). By photon energy dependence and polarization dependence measurements, we resolved the band structure in the three-dimensional momentum space and determined the orbital character of each band. In particular, we found that the dz2 -originated ζ band does not contribute spectral weight to the Fermi surface around Z, unlike BaFe2(As(0.7)P(0.3))2 and Ba(Fe(0.65)Ru(0.35))2As2. Since BaFe2(As(0.7)P(0.3))2 and Ba(Fe(0.65)Ru(0.35))2As2 are nodal superconductors and their hPn's are less than 1.33 Å, while the hPn of Eu(Fe(0.79)Ru(0.21))2As2 is larger than 1.33 Å, our results provide more evidence for a direct relationship between nodes, dz2 orbital character and hPn. Our results help to provide an understanding of the nodal superconductivity in iron-based superconductors.

20.
Phys Rev Lett ; 113(26): 266407, 2014 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-25615365

RESUMO

The electronic structure of the iron-based superconductor Ba2Ti2Fe2As4O (Tc(onset)=23.5 K) has been investigated by using angle-resolved photoemission spectroscopy and combined local density approximation and dynamical mean field theory calculations. The electronic states near the Fermi level are dominated by both the Fe 3d and Ti 3d orbitals, indicating that the spacer layers separating different FeAs layers are also metallic. By counting the enclosed volumes of the Fermi surface sheets, we observe a large self-doping effect; i.e., 0.25 electrons per unit cell are transferred from the FeAs layer to the Ti2As2O layer, leaving the FeAs layer in a hole-doped state. This exotic behavior is successfully reproduced by our dynamical mean field calculations, in which the self-doping effect is attributed to the electronic correlations in the 3d shells. Our work provides an alternative route of effective doping without element substitution for iron-based superconductors.

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