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Objective: To investigate the effects of subcutaneous immunotherapy (SCIT) on patients' immune markers and metabolic levels in the early stage of allergen treatment, and to gain insight into the role of SCIT in regulating immune responses and metabolic levels, so as to provide reference data for the further discovery of potential biomarkers. Methods: A longitudinal study was used to include 40 subjects who underwent SCIT with dust mite allergens in the Department of Pediatrics of the First Affiliated Hospital of Guangzhou Medical University between November 2017 and February 2022, including 20 subjects each of single mite subcutaneous immunotherapy (SM-SCIT) and double mite subcutaneous immunotherapy (DM-SCIT). In this study, levels of dust mite allergen-specific antibodies and polyunsaturated fatty acid metabolism were measured before and 12 months after treatment, while pulmonary function tests were performed. The therapeutic effects of the patients were followed up by visual analogue scale (VAS), asthma control test (ACT) and total medication scores (TMS). The results were statistically analyzed using t-test and Mann-Whitney U-test. Results: After 12 months of treatment with SCIT, both groups showed a significant decrease in total VAS score (SM-SCIT:Z=-2.298, P<0.05; DM-SCIT:Z=-3.411, P<0.001); total ACT score (SM-SCIT:Z=-2.054, P<0.05; DM-SCIT:Z=-2.014, P<0.05) and total medication scores (SM-SCIT:Z=-3.799, P<0.000 1; DM-SCIT:Z=-3.474, P<0.001) were significantly higher, in addition to significantly higher MMEF75/25 values in the DM-SCIT group (t=-2.253, P<0.05). There was no significant change in sIgE in the SM-SCIT group (P>0.05), and the sIgG4 levels of the Der p, Der f, p 1, p 2, f 2, and p 21 fractions were significantly elevated (Z=-2.651, -3.771, -2.949, -2.912, -2.725, -2.128, and -3.285, respectively, all P<0.05); The sIgE of Der p 2, f 2, p 7 and p 23 fractions(Z=-2.651, -3.771, -2.949, -2.912, -2.725, -2.128, -3.285, all P<0.05) and the sIgG4 levels of the Der p, Der f, p 1, p 2, f 1, f 2, p 10, p 21 and p 23 fractions (Z=-3.808, -3.845, -3.061, -2.688, -2.464, -3.211, -2.371, -2.091, -2.427, all P<0.05) of the DM-SCIT group were significantly elevated. Metabolomics analysis showed that arachidonic acid, docosahexaenoic acid, docosapentaenoic acid, eicosapentaenoic acid, 5, 9, 12-octadecatrienoic acid, 5(S)-hydroxylated eicosatetraenoic acid, and dihomo-gamma-linolenic acid were significantly elevated at the beginning of the treatment period after SM-SCIT treatment (Z of -2.191, -2.497, -1.988, -2.090, -2.19, -2.803, -2.073, all P<0.05); 5(S)-hydroxylated eicosatetraenoic acid showed elevated and alpha-linolenic acid, eicosadienoic acid, and eicosapentaenoic acid were significantly decreased in the DM-SCIT group after treatment (Z=-1.988, -2.090, -2.497, -1.988, respectively, all P<0.05). Correlation analysis showed that arachidonic acid was significantly negatively correlated with changes in dust mite-specific IgG4 (r=-0.499, P<0.05), and that alpha-linolenic acid, 5, 9, 12-octadecatrienoic acid, and eicosapentaenoic acid were positively correlated with the ΔsIgG4 of the dust mite der p 2 (r=0.451, 0.420, 0.474, respectively; all P<0.05). Conclusion: Significant changes in allergen-specific antibody levels and polyunsaturated fatty acid metabolism levels occur during SCIT, and the two may interact and influence each other.
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Asma , Desensibilización Inmunológica , Ácidos Grasos Insaturados , Humanos , Animales , Desensibilización Inmunológica/métodos , Asma/terapia , Pyroglyphidae/inmunología , Estudios Longitudinales , Antígenos Dermatofagoides/inmunología , Alérgenos/inmunología , Niño , Inyecciones Subcutáneas , Inmunoglobulina E/inmunologíaRESUMEN
OBJECTIVE: To construct a model of Enterococcus faecalis (E. faecalis) infection in dentinal tubules by gradient centrifugation and to evaluate the antibacterial effect of low-temperature plasma on E. faecalis in dentinal tubules. METHODS: Standard dentin blocks of 4 mm×4 mm×2 mm size were prepared from single root canal isolated teeth without caries, placed in the E. faecalis bacterial solution, centrifuged in gradient and incubated for 24 h to establish the model of dentinal tubule infection with E. faecalis. The twenty dentin blocks of were divided into five groups, low-temperature plasma jet treatment for 0, 5 and 10 min, calcium hydroxide paste sealing for 7 d and 2% chlorhexidine gel sealing for 7 d. Scanning electron microscopy and confocal laser scanning microscope were used to assess the infection in the dentinal tubules and the antibacterial effect of low-temperature plasma. RESULTS: The results of scanning electron microscopy and confocal laser scanning microscopy showed that after 24 h of incubation by gradient centrifugation, E. faecalis could fully enter the dentinal tubules to a depth of more than 600µm indicating that this method was time-saving and efficient and could successfully construct a model of E. faecalis infection in dentinal tubules. Low-temperature plasma could enter the dentinal tubules and play a role, the structure of E. faecalis was still intact after 5 min of low-temperature plasma treatment, with no obvious damage, and after 10 min of low-temperature plasma treatment, the surface morphology of E. faecalis was crumpled and deformed, the cell wall was seriously collapsed, and the normal physiological morphology was damaged indicating that the majority of E. faecalis was killed in the dentinal tubules. The antibacterial effect of low-temperature plasma treatment for 10 min exceeded that of the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d. These two chemicals had difficulty entering deep into the dentinal tubules, and therefore only had a few of antibacterial effect on the bacterial biofilm on the root canal wall, and there was also no significant damage to the E. faecalis bacterial structure. CONCLUSION: Gradient centrifugation could establish the model of E. faecalis dentin infection successfully. Low-temperature plasma treatment for 10 min could kill E. faecalis in dentinal tubules effectively, which is superior to the calcium hydroxide paste sealing for 7 d and the 2% chlorhexidine gel sealing for 7 d.
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Hidróxido de Calcio , Clorhexidina , Clorhexidina/farmacología , Hidróxido de Calcio/farmacología , Enterococcus faecalis/fisiología , Temperatura , Dentina , Biopelículas , Antibacterianos/farmacología , Irrigantes del Conducto Radicular/farmacología , Cavidad PulparRESUMEN
Chemically protected sodium butyrate (CSB) is a new kind of sodium butyrate. Our previous study found that 1,000 mg/kg of CSB had the potential capacity of improving growth performance and promoting early development of small intestine in broilers. This study aimed to investigate the effect of long-term antibiotics or CSB supplementation for intestinal microflora dynamical regulation in broilers. One hundred ninety-two 1-day-old Arbor Acres male broilers were randomly allocated into 3 dietary treatment (8 replicates per treatment) and fed with a basal diet (CON), a diet supplemented with the antibiotics (enramycin, 8 mg/kg and aureomycin, 100 mg/kg) (ANT), or a diet supplemented with 1,000 mg/kg of CSB, respectively. Results showed that dietary supplementation of CSB or ANT treatment elevated the weight gain and feed conversion ratio (FCR; P < 0.05), as compared with control (CON) group. Additionally, CON, CSB, or ANT administration dynamically altered the gut microbiota composition as time goes on. The increased presence of potential pathogens, such as Romboutsia and Shuttleworthia, and decreased beneficial bacteria such as Alistipes, Akkermansia, and Bacteroides were verified in new gut homeostasis reshaped by long-term antibiotics treatment, which has adverse effects on intestinal development and health of broilers. Conversely, CSB supplementation could dynamically enhance the relative abundance of Bacteroides, and decrease Romboutsia and Shuttleworthia in new microflora, which has positive effects on intestinal bacteria of broilers compared with CON group. Meanwhile, CSB supplementation was significantly increased the concentration of propionic acid and total short chain fatty acids (total SCFA; P < 0.05) in comparison with CON and ANT groups. Moreover, CSB treatment significantly increased anti-inflammatory and antioxidative capacities (P < 0.05) of broilers compared with ANT group. Taken together, we revealed characteristic structural changes of gut microbiota throughout long-term CSB or ANT supplementation in broilers, which provided a basic data for evaluating the mechanism of action affecting intestinal health by CSB or ANT administration and CSB as an alternative to antibiotics in the broilers industry.
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Microbioma Gastrointestinal , Masculino , Animales , Ácido Butírico/farmacología , Pollos/fisiología , Alimentación Animal/análisis , Antibacterianos/farmacología , Intestinos , Dieta/veterinaria , Suplementos Dietéticos/análisisRESUMEN
BACKGROUND: Our prospective, open-label, single-arm phase II study investigated the safety and efficacy of DCVAC/LuCa (dendritic cell vaccines for lung cancer) combined with standard carboplatin/pemetrexed in advanced non-squamous (nsq) non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Eligible patients had stage IV nsq NSCLC without oncogenic drivers and had not received prior systemic cancer therapy. Treatment consisted of carboplatin/pemetrexed for up to 6 cycles followed by 21 cycles of pemetrexed maintenance or until progression or intolerance. Non-progression patients after two cycles of chemotherapy started to receive DCVAC/LuCa subcutaneously (s.c.) on day 15 of cycle 3, and thereafter q3w (day 15 of chemotherapy cycles) for up to 15 doses. Dosing of DCVAC/LuCa s.c. varied among patients depending on the baseline number of leucocytes but remained constant for each single patient. Safety was assessed by adverse events (AEs), treatment-related adverse events (TRAEs), serious adverse events (SAEs), and adverse events of special interest (AESIs). Efficacy was measured by overall survival (OS), progression-free survival (PFS), time to progression (TTP), and objective response rate (ORR). RESULTS: Sixty-one patients were enrolled. In the safety population (n = 60), eight patients (13.33%) had grade 3 or greater TRAEs, and six patients (10.0%) showed SAEs which were not related to leukapheresis or DC vaccination. Six grade 1 AEs were considered to be related to leukapheresis. No AESIs or DCVAC/LuCa-induced AEs were observed. The 2-year survival rate in the modified intention-to-treat population (n = 44) was 52.57%. Median OS was not reached. Median PFS was 8.0 months, median TTP was 10.2 months, and the ORR was 31.82%. CONCLUSION: In treatment-naïve stage IV nsq NSCLC patients without oncogenic drivers, the combination of carboplatin/pemetrexed and DCVAC/LuCa was well tolerated and showed promising efficacy. Therefore, a study to prove our immunotherapeutic concept in a randomized phase III trial is planned.
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Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Acetilcisteína/análogos & derivados , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Carboplatino/farmacología , Carboplatino/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Células Dendríticas , Humanos , Inmunoterapia/efectos adversos , Neoplasias Pulmonares/tratamiento farmacológico , Pemetrexed/farmacología , Pemetrexed/uso terapéutico , Estudios ProspectivosRESUMEN
Objective: To investigate the clinicopathological features and prognostic factors of primary mediastinal large B-cell lymphoma (PMBL). Methods: The clinical data of 60 patients with PMBL including 44 biopsy cases and 16 consultation cases from September 2000 to November 2019 in the Department of Pathology, China-Japan Friendship Hospital (14 cases) and Peking Union Medical College Hospital (46 cases) were enrolled. Pathologic features, immunophenotype, immunoglobulin (Ig) gene rearrangement and microRNA expression profile were retrospectively studied. Results: Of the 60 patients, 23 were males and 37 were females, age ranged from 15 to 64 years (median 28 years). Immunohistochemical staining showed that the tumor cells were positive for pan-B cell antigens, CD30 (77.4%, 24/31), CD23 (73.1%, 19/26), MUM1 (45.8%, 11/24), Ki-67 index ≥70 % (90.6%, 29/32). EBER in situ hybridization was analyzed in 21 PMBL, only one case (4.8%) was positive. Ig gene rearrangement was performed in 20 cases, and seven were positive (35.0%). MicroRNA gene expression profiles were analyzed in seven cases of PMBL and nine cases of diffuse large B-cell lymphoma, and there were 33 microRNAs with significant difference (P<0.05). Univariate analysis indicated that the poor prognostic factors included serum lactate dehydrogenase (LDH) level,International Prognostic Index (IPI) score ≥3, stages â ¢-â £, chemotherapy not combined with rituximab and MUM1 positivity (P<0.05). Multivariate analysis showed that the treatment combined with rituximab was independently related to prognosis (P<0.05). Conclusions: PMBL is different from diffuse large B-cell lymphoma in clinicopathologic features, immunophenotypic presentation and molecular features. The prognostic factors, molecular genetics and immunological characteristics reveal that this study has enriched our understanding of the biology of PMBL, thus providing evidence and strategies for treatment.
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Linfoma de Células B Grandes Difuso , Neoplasias del Mediastino , MicroARNs , Adolescente , Adulto , Femenino , Humanos , Linfoma de Células B Grandes Difuso/tratamiento farmacológico , Linfoma de Células B Grandes Difuso/genética , Masculino , Neoplasias del Mediastino/tratamiento farmacológico , Neoplasias del Mediastino/genética , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Adulto JovenRESUMEN
Epigenetics refers to genetic regulation patterns that gene expressions, which lead to the phenotype variance, are modified in the absence of changes of DNA sequence. Epigenetics mainly includes DNA methylation, histone modification, and non-coding RNA regulation. During the development of the teeth, conventional gene regulation and epigenetics synergistically regulate the spatial and temporal expression of genes, which involved in cell proliferation, differentiation and finally the formation of teeth. Exploration of the epigenetic regulation mechanisms during tooth development can provide multiple clues and ideas for the research of tooth regeneration. This article reviewed the significant roles of epigenetic regulation in tooth development.
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Epigénesis Genética , Odontogénesis , Diferenciación Celular , Metilación de ADN , Regulación de la Expresión Génica , Odontogénesis/genéticaRESUMEN
Ruminants can tolerate moderate concentrations of dietary tannin, making it feasible to replace corn with sorghum in ruminant diets; however, conditioning temperature of pelleted total mixed ration (PTMR) greatly affects nutrient digestibility. The objective was to determine effects of grain type and conditioning temperature during pelleting on growth performance, ruminal fermentation, meat quality and blood metabolites of fattening lambs. This was a 2â¯×â¯3 factorial study, with corn and sorghum and three conditioning temperatures (65, 75 and 85⯰C) in a randomized complete design, with 36 lambs (120⯱â¯10.2 d and 24.9⯱â¯3.3â¯kg) grouped by weight and randomly allocated. The resulting six PTMRs were referred to as 65-S, 75-S and 85-S for sorghum-based diets, and 65-C, 75-C and 85-C for corn-based diets, for low, medium and high pelleting temperatures, respectively. There was no grain type × conditioning temperature (Grain × Temp) interaction on growth performance and apparent nutrient digestibility. Furthermore, grain type did not affect DM intake (DMI), average daily gain (ADG) or feed conversion ratio (FCR) of fattening lambs. Pelleting at 75⯰C improved ADG (Pâ¯<â¯0.03) and FCR (Pâ¯<â¯0.02) of fattening lambs compared to other temperatures. There was a Grain × Temp interaction (Pâ¯<â¯0.01) on ruminal pH (lowest in lambs fed 75-S). There tended (Pâ¯=â¯0.07) to be a Grain × Temp interaction for total volatile fatty acid (VFA), and there were Grain × Temp interactions for molar proportions of acetate (Pâ¯<â¯0.04), butyrate (Pâ¯<â¯0.03) and branch-chained VFA (Pâ¯<â¯0.01). Lambs fed sorghum-based PTMR had greater molar proportion of propionate (Pâ¯<â¯0.03) and lower acetate to propionate ratio (A:P, Pâ¯<â¯0.04). Lambs fed sorghum-based PTMR had higher plasma concentrations of urea nitrogen (N) (Pâ¯<â¯0.03), glucose (Pâ¯<â¯0.01) and alkaline phosphatase (Pâ¯<â¯0.05), whereas other blood metabolites were not affected by treatments. There were Grain × Temp (Pâ¯<â¯0.03) interactions for color coordinates of longissimus and mid-gluteal muscle. Lambs fed sorghum-based PTMR had lower (Pâ¯<â¯0.01) dressing percentage and meat quality than those fed corn-based PTMR. We concluded that sorghum can replace corn in lamb diets without compromising growth performance and feed efficiency; furthermore, feeding sorghum vs corn improved rumen fermentation, with reduced A:P ratio and enhanced N and glucose utilization. Finally, pelleting at 75⯰C increased feeding value of either sorghum- or corn-based PTMR for fattening lambs.
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Alimentación Animal , Rumen , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Digestión , Fermentación , Carne , Rumen/metabolismo , Ovinos , Temperatura , Zea maysRESUMEN
Purpose Immune cells in the immune microenvironment of lung cancer have a great impact on the development of lung cancer. Our purpose was to analyze the immune cell infiltration features and related marker genes for lung cancer. Methods Single cell RNA sequencing data of 11,485 lung cancer cells were retrieved from the Gene Expression Omnibus. After quality control and data normalization, cell clustering was performed using the Seurat package. Based on the marker genes of each cell type from the CellMarker database, each cell was divided into G1, G2M, and S phases. Then, differential expression and functional enrichment analyses were performed. CIBERSORT was used to reconstruct immune cell types. Results Following cell filtering, highly variable genes were identified for all cells. 14 cell types were clustered. Among them, CD4 + T cell, B cell, plasma cell, natural killer cell and cancer stem cell were the top five cell types. Up-regulated genes were mainly enriched in immune-related biological processes and pathways. Using CIBERSORT, we identified the significantly higher fractions of naïve B cell, memory CD4 + T cell, T follicular helper cell, T regulatory helper cell and M1 macrophage in lung cancer tissues compared to normal tissues. Furthermore, the fractions of resting NK cell, monocyte, M0 macrophage, resting mast cell, eosinophil and neutrophil were significantly lower in tumor tissues than normal tissues. Conclusion Our findings dissected the immune cell infiltration features and related marker genes for lung cancer, which might provide novel insights for the immunotherapy of lung cancer (AU)
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Humanos , Marcadores Genéticos/genética , Inmunidad Celular/genética , Inmunidad Celular/inmunología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Linfocitos B/inmunología , Linfocitos T CD4-Positivos/inmunología , Regulación Neoplásica de la Expresión Génica , Microambiente Tumoral/inmunología , Regulación hacia AbajoRESUMEN
In strongly correlated systems the strength of Coulomb interactions between electrons, relative to their kinetic energy, plays a central role in determining their emergent quantum mechanical phases. We perform resonant x-ray scattering on Bi2Sr2CaCu2O8+δ, a prototypical cuprate superconductor, to probe electronic correlations within the CuO2 plane. We discover a dynamic quasi-circular pattern in the x-y scattering plane with a radius that matches the wave vector magnitude of the well-known static charge order. Along with doping- and temperature-dependent measurements, our experiments reveal a picture of charge order competing with superconductivity where short-range domains along x and y can dynamically rotate into any other in-plane direction. This quasi-circular spectrum, a hallmark of Brazovskii-type fluctuations, has immediate consequences to our understanding of rotational and translational symmetry breaking in the cuprates. We discuss how the combination of short- and long-range Coulomb interactions results in an effective non-monotonic potential that may determine the quasi-circular pattern.
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PURPOSE: Immune cells in the immune microenvironment of lung cancer have a great impact on the development of lung cancer. Our purpose was to analyze the immune cell infiltration features and related marker genes for lung cancer. METHODS: Single cell RNA sequencing data of 11,485 lung cancer cells were retrieved from the Gene Expression Omnibus. After quality control and data normalization, cell clustering was performed using the Seurat package. Based on the marker genes of each cell type from the CellMarker database, each cell was divided into G1, G2M, and S phases. Then, differential expression and functional enrichment analyses were performed. CIBERSORT was used to reconstruct immune cell types. RESULTS: Following cell filtering, highly variable genes were identified for all cells. 14 cell types were clustered. Among them, CD4 + T cell, B cell, plasma cell, natural killer cell and cancer stem cell were the top five cell types. Up-regulated genes were mainly enriched in immune-related biological processes and pathways. Using CIBERSORT, we identified the significantly higher fractions of naïve B cell, memory CD4 + T cell, T follicular helper cell, T regulatory helper cell and M1 macrophage in lung cancer tissues compared to normal tissues. Furthermore, the fractions of resting NK cell, monocyte, M0 macrophage, resting mast cell, eosinophil and neutrophil were significantly lower in tumor tissues than normal tissues. CONCLUSION: Our findings dissected the immune cell infiltration features and related marker genes for lung cancer, which might provide novel insights for the immunotherapy of lung cancer.
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Marcadores Genéticos/genética , Inmunidad Celular , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , RNA-Seq/métodos , Linfocitos B/citología , Linfocitos T CD4-Positivos/citología , Ciclo Celular , Bases de Datos Genéticas , Expresión Génica , Humanos , Inmunidad Celular/genética , Células Asesinas Naturales/citología , Macrófagos/citología , Células Madre Neoplásicas/citología , Células Plasmáticas/citología , Células T Auxiliares Foliculares/citología , Linfocitos T Reguladores/citología , Microambiente Tumoral/inmunología , Regulación hacia ArribaRESUMEN
Objective: To analyze whether there is a difference in the influence of coronary artery disease (CAD) on the clinical features and prognosis of three different types of heart failure patients. Methods: Complete clinical data of 1 520 hospitalized patients with heart failure from Tianjin Medical University General Hospital and Tianjin Chest Hospital from March 2014 to February 2016 was retrospectively reviewed. According to left ventricular ejection fraction (LVEF), the patients were divided into three groups: heart failure with reduced ejection fraction group (HFrEF), heart failure with mid-range ejection fraction group (HFmrEF)and heart failure with preserved ejection fraction group (HFpEF). Each group was further classified into two subgroups according to absence or presence of CAD (No CAD' and 'With CAD'). In the HFrEF group, 197 patients were categorized into 'No CAD' sub-group while 435 patients were into 'With CAD' sub-group. Likewise, 63 patients in HFmrEF group fell into 'No CAD' sub-group while 367 were into 'With CAD' sub-group. Seventy two patients in the HFpEF group were in the 'No CAD' sub-group with 386 in the 'With CAD' sub-group. Clinical features and 2-year prognosis between different subgroups were compared. Results: (1) The relationship between CAD and clinical features of different types of heart failure: the proportions of HFrEF, HFmrEF and HFpEF combined with CAD were 68.8%, 85.3% and 84.3%, respectively (P<0.05). Compared with the 'No CAD' subgroups, patients in the 'With CAD' subgroups were older, and had higher NT-proBNP levels, higher rates of hypertension and diabetes, and lower rates of atrial fibrillation. Also, there were more use of antiplatelet and nitrate drugs in the 'With CAD' sub-groups (P<0.05). (2) Risk of different types of heart failure combined with CAD: after multivariate adjustment, HFrEF had a lower risk of CAD (HFrEF vs HFmrEF: RR=0.389, 95%CI 0.281-0.540; HFrEF vs HFpEF: RR=0.408, 95%CI 0.298-0.560). (3)The influence of CAD on the prognosis of different types of heart failure: CAD increased the risk of mortality in the HFrEF group (HR=1.631, 95%CI 1.119-2.377), and cardiovascular events in all three types of heart failure (HR: HFrEF 1.725, 95%CI 1.325-2.246; HFmrEF 1.815, 95%CI 1.144-2.879; HFpEF 1.900, 95%CI 1.218-2.963). Conclusions: Patients with HFmrEF and HFpEF have a higher prevalence and risk of CAD than patients with HFrEF. CAD is associated with an increased risk of cardiovascular events in all types of heart failure and increases the risk of all-cause mortality among HFrEF group. CAD is an important factor influencing the clinical features and prognosis of patients with all types of heart failure.
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Enfermedad de la Arteria Coronaria , Insuficiencia Cardíaca , Humanos , Pronóstico , Estudios Retrospectivos , Volumen Sistólico , Función Ventricular IzquierdaRESUMEN
Establishing the presence and the nature of a quantum critical point in their phase diagram is a central enigma of the high-temperature superconducting cuprates. It could explain their pseudogap and strange metal phases, and ultimately their high superconducting temperatures. Yet, while solid evidences exist in several unconventional superconductors of ubiquitous critical fluctuations associated to a quantum critical point, in the cuprates they remain undetected until now. Here using symmetry-resolved electronic Raman scattering in the cuprate [Formula: see text], we report the observation of enhanced electronic nematic fluctuations near the endpoint of the pseudogap phase. While our data hint at the possible presence of an incipient nematic quantum critical point, the doping dependence of the nematic fluctuations deviates significantly from a canonical quantum critical scenario. The observed nematic instability rather appears to be tied to the presence of a van Hove singularity in the band structure.
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Zirconium pentatelluride was recently reported to be a 3D Dirac semimetal, with a single conical band, located at the center of the Brillouin zone. The cone's lack of protection by the lattice symmetry immediately sparked vast discussions about the size and topological or trivial nature of a possible gap opening. Here, we report on a combined optical and transport study of ZrTe_{5}, which reveals an alternative view of electronic bands in this material. We conclude that the dispersion is approximately linear only in the a-c plane, while remaining relatively flat and parabolic in the third direction (along the b axis). Therefore, the electronic states in ZrTe_{5} cannot be described using the model of 3D Dirac massless electrons, even when staying at energies well above the band gap 2Δ=6 meV found in our experiments at low temperatures.
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SrxBi2Se3 and the related compounds CuxBi2Se3 and NbxBi2Se3 have attracted considerable interest, as these materials may be realizations of unconventional topological superconductors. Superconductivity with Tc ~3 K in SrxBi2Se3 arises upon intercalation of Sr into the layered topological insulator Bi2Se3. Here we elucidate the anisotropy of the normal and superconducting state of Sr0.1Bi2Se3 with angular dependent magnetotransport and thermodynamic measurements. High resolution x-ray diffraction studies underline the high crystalline quality of the samples. We demonstrate that the normal state electronic and magnetic properties of Sr0.1Bi2Se3 are isotropic in the basal plane while we observe a large two-fold in-plane anisotropy of the upper critical field in the superconducting state. Our results support the recently proposed odd-parity nematic state characterized by a nodal gap of Eu symmetry in SrxBi2Se3.
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A central mystery in high-temperature superconductivity is the origin of the so-called strange metal (i.e., the anomalous conductor from which superconductivity emerges at low temperature). Measuring the dynamic charge response of the copper oxides, [Formula: see text], would directly reveal the collective properties of the strange metal, but it has never been possible to measure this quantity with millielectronvolt resolution. Here, we present a measurement of [Formula: see text] for a cuprate, optimally doped Bi2.1Sr1.9CaCu2O8+x (Tc = 91 K), using momentum-resolved inelastic electron scattering. In the medium energy range 0.1-2 eV relevant to the strange metal, the spectra are dominated by a featureless, temperature- and momentum-independent continuum persisting to the electronvolt energy scale. This continuum displays a simple power-law form, exhibiting q2 behavior at low energy and q2/ω2 behavior at high energy. Measurements of an overdoped crystal (Tc = 50 K) showed the emergence of a gap-like feature at low temperature, indicating deviation from power law form outside the strange-metal regime. Our study suggests the strange metal exhibits a new type of charge dynamics in which excitations are local to such a degree that space and time axes are decoupled.
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The possibility of driving phase transitions in low-density condensates through the loss of phase coherence alone has far-reaching implications for the study of quantum phases of matter. This has inspired the development of tools to control and explore the collective properties of condensate phases via phase fluctuations. Electrically gated oxide interfaces1,2, ultracold Fermi atoms3,4 and cuprate superconductors5,6, which are characterized by an intrinsically small phase stiffness, are paradigmatic examples where these tools are having a dramatic impact. Here we use light pulses shorter than the internal thermalization time to drive and probe the phase fragility of the Bi2Sr2CaCu2O8+δ cuprate superconductor, completely melting the superconducting condensate without affecting the pairing strength. The resulting ultrafast dynamics of phase fluctuations and charge excitations are captured and disentangled by time-resolved photoemission spectroscopy. This work demonstrates the dominant role of phase coherence in the superconductor-to-normal state phase transition and offers a benchmark for non-equilibrium spectroscopic investigations of the cuprate phase diagram.
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Background: MYC is a well-established cancer driver gene regulating the expression of numerous genes, indicating that polymorphisms in MYC response elements could affect tumorigenesis through altering MYC regulation. We performed integrative multistage study to evaluate the effects of variants in MYC response elements and colorectal cancer (CRC) risk. Patients and methods: We systematically integrated ChIP-Seq, DNase-Seq and transcription factor motif data to screen variants with potential ability to affect the MYC binding affinity. Then, we conducted a two-stage case-control study, totally consisting of 4830 CRC cases and 4759 controls in Chinese population to identify risk polymorphisms and interactions. The effects of risk variants were confirmed by functional assays in CRC LoVo, SW480 and HCT15 cells. Results: We identified a novel polymorphism rs11777210 in KBTBD11 significantly associated with CRC susceptibility (P = 2.43 × 10-12). Notably, we observed a significant interaction between rs11777210 and MYC nearby rs6983267 (P-multi = 0.003, P-add = 0.005), subjects carrying rs6983267 GG and rs11777210 CC genotypes showing higher susceptibility to CRC (2.83-fold) than those carrying rs6983267 TT and rs11777210 TT genotypes. We further demonstrated that rs6983267 T > G increased MYC expression, and MYC bound to and negatively regulated KBTBD11 expression when the rs11777210 C risk allele was present. KBTBD11 was downregulated in tumor tissues, and KBTBD11 knockdown promoted cell proliferation and inhibited cell apoptosis. Conclusion: The rs11777210 is a potential predictive biomarker of CRC susceptibility, and KBTBD11 functions as a putative tumor suppressor in tumorigenesis. Our study highlighted the high CRC risk of people carrying rs6983267 G and rs11777210 C alleles, and provided possible biological mechanism of the interaction.
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Neoplasias Colorrectales/genética , Regulación Neoplásica de la Expresión Génica/genética , Predisposición Genética a la Enfermedad/genética , Proteínas Proto-Oncogénicas c-myc/genética , Elementos de Respuesta/genética , Genotipo , Humanos , Polimorfismo de Nucleótido SimpleRESUMEN
INTRODUCTION: Red blood cell distribution width (RDW) and bilirubin have been proved to be prognostic factors for various types of cancer. However, their prognostic value in patients with gastric cancer (GC) remains largely unknown. METHODS: To verify whether RDW and bilirubin are prognostic factors for patients with GC, we performed a cross-sectional study to analyze the relationship between RDW, bilirubin, and the clinical characteristics of patients with GC. Medical records of all newly diagnosed and pathologically proved patients with GC admitted to Changzheng Hospital between January 2016 and July 2016 were retrospectively reviewed. The relationship between RDW, bilirubin, and the clinical characteristics of patients with GC was analyzed. RESULTS: A total of 144 patients with GC were enrolled. Patients with GC had significantly higher RDW than healthy controls, even after adjusting for hemoglobin, while total bilirubin (TBIL), direct bilirubin (DBIL) and indirect bilirubin (IBIL) were significantly decreased. Furthermore, RDW and bilirubin were significantly correlated with tumor stage, as well as carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9). CONCLUSION: Our study indicated that RDW and bilirubin could be potential prognostic factors for patients of GC.
Asunto(s)
Bilirrubina/sangre , Índices de Eritrocitos , Neoplasias Gástricas/sangre , Neoplasias Gástricas/diagnóstico , Anciano , Biomarcadores de Tumor , Recuento de Células Sanguíneas , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios RetrospectivosRESUMEN
PURPOSE: To test if active breath control during cone-beam computed tomography (CBCT) could improve planning target volume during accelerated partial breast radiotherapy for breast cancer. METHODS: Patients who were more than 40 years old, underwent breast-conserving dissection and planned for accelerated partial breast irradiation, and with postoperative staging limited to T1-2 N0 M0, or postoperative staging T2 lesion no larger than 3cm with a negative surgical margin greater than 2mm were enrolled. Patients with lobular carcinoma or extensive ductal carcinoma in situ were excluded. CBCT images were obtained pre-correction, post-correction and post-treatment. Set-up errors were recorded at left-right, anterior-posterior and superior-inferior directions. The differences between these CBCT images, as well as calculated radiation doses, were compared between patients with active breath control or free breathing. RESULTS: Forty patients were enrolled, among them 25 had active breath control. A total of 836 CBCT images were obtained for analysis. CBCT significantly reduced planning target volume. However, active breath control did not show significant benefit in decreasing planning target volume margin and the doses of organ-at-risk when compared to free breathing. CONCLUSION: CBCT, but not active breath control, could reduce planning target volume during accelerated partial breast irradiation.