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1.
Phys Rev Lett ; 130(21): 216004, 2023 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-37295091

RESUMO

There has been a long-standing debate about the mechanism of the unusual superconductivity in alkali-intercalated fullerides. In this Letter, using high-resolution angle-resolved photoemission spectroscopy, we systematically investigate the electronic structures of superconducting K_{3}C_{60} thin films. We observe a dispersive energy band crossing the Fermi level with the occupied bandwidth of about 130 meV. The measured band structure shows prominent quasiparticle kinks and a replica band involving the Jahn-Teller active phonon modes, which reflects strong electron-phonon coupling in the system. The electron-phonon coupling constant is estimated to be about 1.2, which dominates the quasiparticle mass renormalization. Moreover, we observe an isotropic nodeless superconducting gap beyond the mean-field estimation (2Δ/k_{B}T_{c}≈5). Both the large electron-phonon coupling constant and large reduced superconducting gap suggest a strong-coupling superconductivity in K_{3}C_{60}, while the electronic correlation effect is suggested by the observation of a waterfall-like band dispersion and the small bandwidth compared with the effective Coulomb interaction. Our results not only directly visualize the crucial band structure but also provide important insights into the mechanism of the unusual superconductivity of fulleride compounds.


Assuntos
Álcalis , Elétrons , Espectroscopia Fotoeletrônica
2.
Zhonghua Shao Shang Za Zhi ; 35(10): 733-739, 2019 Oct 20.
Artigo em Chinês | MEDLINE | ID: mdl-31658544

RESUMO

Objective: To preliminarily investigate the effect of intraoperative goal-directed fluid management (GDFM) on pulmonary function and oxygen dynamics in patients with severe burns. Methods: From February 2017 to May 2018, 30 patients admitted to Burn Department of our hospital with severe burns who met the criteria for inclusion and needed escharectomy and skin grafting were enrolled in this prospective randomized controlled trial. The patients were divided into group GDFM of 15 cases [14 males and 1 female, (45±14) years old] and conventional liquid management group of 15 cases [12 males and 3 females, (42±10) years old] according to the random number table. During escharectomy and skin grafting, volume of patients in group GDFM was managed according to the GDFM scheme, based on cardiac output index, stroke volume variation, stroke volume index, hemoglobin, central venous oxygen saturation (ScvO(2)), and other parameters; volume of patients in conventional liquid management group was managed according to clinical experience and conventional liquid management scheme, based on mean arterial pressure, central venous pressure, urine output, hemoglobin, and other parameters. At post operation hour (POH) 1, 6, 12, and 24, arterial and venous blood was collected from patients of the two groups to determine the levels of extravascular lung water index (ELWI), global end-diastolic volume index (GEDI), oxygenation index, ScvO(2), central venous-to-arterial blood carbon dioxide partial pressure difference (Pcv-aCO(2)), lactic acid, pH value, bicarbonate ion, and base excess routinely. Data were processed with Fisher's exact probability test, t test, analysis of variance for repeated measurement, and least significant difference test. Results: (1) The ELWI of patients in group GDFM was (4.3±1.1) mL/kg at POH 1, which was significantly lower than (6.5±3.6) mL/kg in conventional liquid management group (t=2.26, P<0.05). The ELWI levels of patients in group GDFM at POH 6, 12, and 24 were (6.8±2.2), (6.6±2.0), and (6.9±1.6) mL/kg, respectively, significantly higher than the level at POH 1 within the same group (P<0.01), and similar to (8.5±3.1), (7.8±2.3), and (8.0±3.5) mL/kg in conventional liquid management group (t=1.73, 1.53, 1.10, P>0.05). The GEDI levels between patients of the two groups were similar, and there was no significantly statistical difference between the two groups as a whole (treatment factor main effect F=2.35, time factor main effect F=0.44, interaction F=0.07, P>0.05). (2) The oxygenation index of patients in group GDFM was (350±78) mL/kg at POH 1, which was significantly higher than (259±109) mL/kg in conventional liquid management group (t=2.63, P<0.05). In conventional liquid management group, the oxygenation index of patients at POH 6 was significantly higher than that at POH 1, 12, or 24 (P<0.01). The ScvO(2) levels of patients in group GDFM at POH 1, 6, and 12 were 0.516±0.105, 0.679±0.121, and 0.713±0.104, respectively, which were significantly higher than 0.382±0.194, 0.545±0.194, and 0.595±0.191 in conventional liquid management group (t=2.35, 2.27, 2.10, P<0.05). The ScvO(2) levels of patients in the two groups at POH 6, 12, and 24 were significantly higher than those levels at POH 1 within the same group (P<0.01), and the ScvO(2) of patients in conventional liquid management group at POH 24 was significantly higher than that at POH 6 or 12 within the same group (P<0.05 or P<0.01). The Pcv-aCO(2) levels of patients in group GDFM were significantly lower than those in conventional liquid management group at POH 1 and 6 (t=2.55, 2.71, P<0.05). The Pcv-aCO(2) of patients in group GDFM at POH 12 was significantly lower than that at POH 6 or 24 within the same group (P<0.05). (3) The blood lactic acid levels and pH values between patients of the two groups were similar at POH 1, 6, 12, and 24 (t=0.89, 0.19, 0.26, 0.23; 1.55, 0.71, 0.77, 0.77, P>0.05). In conventional liquid management group, the blood lactic acid levels of patients at POH 6, 12, and 24 were significantly lower than the level at POH 1 within the same group (P<0.05), and the pH values of patients at POH 6, 12, and 24 were significantly higher than the value at POH 1 within the same group (P<0.05). The levels of bicarbonate ion and base excess between patients of the two groups were similar, and there were no significantly statistical differences between the two groups as a whole (treatment factor main effect F=0.06, 0.11, time factor main effect F=2.07, 1.59, interaction F=1.45, 0.91, P>0.05). Conclusions: GDFM is helpful to improve the pulmonary function and oxygen dynamics in patients with severe burns in the short term after escharectomy and skin grafting. It has certain significance in preventing and reducing pulmonary edema and pulmonary complications in patients with severe burn after operation.


Assuntos
Queimaduras/terapia , Hidratação/métodos , Pulmão/fisiologia , Oxigênio , Adulto , Queimaduras/complicações , Pressão Venosa Central , Feminino , Objetivos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Transplante de Pele , Resultado do Tratamento
3.
Scand J Rheumatol ; 46(3): 210-214, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27684961

RESUMO

OBJECTIVES: Polymorphisms of IKAROS family zinc finger 1 (IKZF1) have been found to be associated with systemic lupus erythematosus (SLE) by genome-wide association studies (GWAS). The aim of the current study was to investigate the association between IKZF1 functional variants and lupus nephritis (LN) in a northern Han Chinese population and analyse their relationship with clinical and pathological phenotypes in LN. METHOD: The association between IKZF1 functional variants and LN was analysed for the lead variant rs1456896 with both GWAS and expression quantitative trait loci (eQTL) top hits in 500 LN patients and 500 healthy controls. Replication was conducted in an independent cohort comprising 798 LN patients and 704 healthy controls. Using the ENCODE (Encyclopedia of DNA Elements) databases, functional annotations and differential gene expression data were evaluated. RESULTS: A significant association between the single nuclear polymorphism (SNP) rs1456896 and susceptibility to LN was observed in the two different cohorts (p = 9.32 × 10-3 and p = 3.00 × 10-2) and reinforced in combination (p = 1.36 × 10-3). In silico analysis indicates that rs1456896 is a regulatory variant and lower mRNA expressions of IKZF1 were observed in both peripheral blood mononuclear cells (PBMCs) and renal biopsies from SLE patients compared to normal controls. Although patients with the protective genotype AA of rs1456896 seemed to have more pronounced clinical manifestations and a lower ratio of histological classes III and IV, no significant associations between rs1456896 genotypes and sub-phenotypes of LN were detected. CONCLUSIONS: Our results suggest that the rs1456896 A allele is associated with protective susceptibility to LN. However, this association did not seem to be implicated in the disease and histopathological severity of LN in the current population.


Assuntos
Povo Asiático/genética , Fator de Transcrição Ikaros/genética , Nefrite Lúpica/genética , Regiões 5' não Traduzidas/genética , Adulto , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Modelos Logísticos , Nefrite Lúpica/patologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de Proteção , Índice de Gravidade de Doença
4.
Genes Immun ; 16(3): 231-7, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25675412

RESUMO

IgA nephropathy (IgAN) is a complex syndrome with high genetic heterogeneity. More recently, a genome-wide association study (GWAS) from Southern Han population revealed that variants within 8p23.1, where the DEFA genes encoding a-defensins assembled, were associated with susceptibility to IgAN. To replicate the association and fine-map the genetic variants, a case-control genetic study from an independent Northern Han cohort was conducted. A total of 60 single-nucleotide polymorphisms in a region spanning 350 kb encompassing the DEFA genes cluster were analyzed in 2096 individuals. Copy number variations of DEFA1A3 within the loci were also checked for the independent association. Functional significance of the associated variants was further examined by the in silico method as well as by cis-acting expression quantitative trait loci analysis with mRNA. It showed that 17 out of 60 (28.3%) variants were associated with susceptibility to IgAN. Two independent signals with functional potentials were discovered (rs2738058, P=4.64 × 10(-5), odds ratio (OR)=0.76, 95% confidence interval (CI) 0.66-0.87 and rs9644778, P=4.78 × 10(-3), OR=1.21, 95% CI 1.06-1.39). Besides, marginally significant association of rs9644778 risk genotype with lower proportion of gross hematuria (CC+CA vs AA 35.2% vs 30.2%, P=0.073) was observed. In conclusion, DEFA gene polymorphisms have potentially pathogenic roles in IgAN, and the role of mucosal immunity in the pathogenesis of IgAN has to be emphasized.


Assuntos
Povo Asiático/genética , Proteína DEFICIENS/genética , Estudos de Associação Genética , Predisposição Genética para Doença , Variação Genética , Glomerulonefrite por IGA/epidemiologia , Glomerulonefrite por IGA/genética , Alelos , Estudos de Casos e Controles , China/epidemiologia , Variações do Número de Cópias de DNA , Feminino , Expressão Gênica , Ligação Genética , Genótipo , Glomerulonefrite por IGA/diagnóstico , Humanos , Desequilíbrio de Ligação , Masculino , Família Multigênica , Razão de Chances , Peptídeos Cíclicos/genética , Fenótipo , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas , Índice de Gravidade de Doença , alfa-Defensinas/genética
5.
Sheng Wu Gong Cheng Xue Bao ; 17(3): 246-9, 2001 May.
Artigo em Chinês | MEDLINE | ID: mdl-11517593

RESUMO

Hansenula polymorpha is a potential host for foreign gene expression, which has been applied widely in academic studying and industry application. It has a number of advantages of expressing genes derived from eukaryotic organisms, such as mitotically stable recombinant strains, faithful processing of the produced polypeptides, and high productivity et al. Numerous foreign proteins with high commercial value have been expressed successfully in H. polymorpha, among which some have been launched on the market. In this review, the favorable characteristics of this system for foreign gene production and new advances are described.


Assuntos
Engenharia Genética , Pichia/genética , Fermentação , Expressão Gênica
6.
J Tongji Med Univ ; 13(4): 218-20, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8151740

RESUMO

Clinical and prognostic investigations were conducted in 46 cases of M2/t(8;21) leukemia and 29 cases of M2/NN patients. Results showed that most patients with M2/t(8;21) were young males with higher incidence of extramedullary infiltrations. Complete remission rate was higher but with earlier relapse. The prognosis of patients with M2/t(8;21) with loss of one sexual chromosome was poor.


Assuntos
Cromossomos Humanos Par 12 , Cromossomos Humanos Par 8 , Leucemia Mieloide Aguda/genética , Translocação Genética , Adulto , Aberrações Cromossômicas , Feminino , Humanos , Masculino , Prognóstico , Cromossomo Y
7.
Ann Ophthalmol ; 21(8): 303-5, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2802454

RESUMO

We describe clinical and pathologic characteristics of two cases of traumatic intracorneal cyst. Both patients were children, without a history of ocular surgery, but they had been injured by scissors many years before the corneal lesion was noted. The corneal lesion was characteristically circular, opalescent, quiet, and slowly progressive. Histopathologically it formed within the corneal lamellae and was lined by corneal epithelium. Some epithelial debris was noted in the cyst contents. The first case was treated with penetrating keratoplasty, and the graft remained clear after 11 months of follow-up. The second case received simple aspiration, and recurrence of the cyst was noted at a nine-month follow-up. Excision of the anterior cyst wall and chemical cauterization using aqueous iodine 1% was done subsequently.


Assuntos
Doenças da Córnea/cirurgia , Lesões da Córnea , Cistos/cirurgia , Criança , Doenças da Córnea/etiologia , Cistos/etiologia , Feminino , Humanos , Masculino
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