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1.
Am J Transplant ; 24(5): 839-849, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38266712

RESUMO

Lung transplantation lags behind other solid organ transplants in donor lung utilization due, in part, to uncertainty regarding donor quality. We sought to develop an easy-to-use donor risk metric that, unlike existing metrics, accounts for a rich set of donor factors. Our study population consisted of n = 26 549 adult lung transplant recipients abstracted from the United Network for Organ Sharing Standard Transplant Analysis and Research file. We used Cox regression to model graft failure (GF; earliest of death or retransplant) risk based on donor and transplant factors, adjusting for recipient factors. We then derived and validated a Lung Donor Risk Index (LDRI) and developed a pertinent online application (https://shiny.pmacs.upenn.edu/LDRI_Calculator/). We found 12 donor/transplant factors that were independently predictive of GF: age, race, insulin-dependent diabetes, the difference between donor and recipient height, smoking, cocaine use, cytomegalovirus seropositivity, creatinine, human leukocyte antigen (HLA) mismatch, ischemia time, and donation after circulatory death. Validation showed the LDRI to have GF risk discrimination that was reasonable (C = 0.61) and higher than any of its predecessors. The LDRI is intended for use by transplant centers, organ procurement organizations, and regulatory agencies and to benefit patients in decision-making. Unlike its predecessors, the proposed LDRI could gain wide acceptance because of its granularity and similarity to the Kidney Donor Risk Index.


Assuntos
Rejeição de Enxerto , Sobrevivência de Enxerto , Transplante de Pulmão , Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Humanos , Transplante de Pulmão/efeitos adversos , Feminino , Masculino , Doadores de Tecidos/provisão & distribuição , Pessoa de Meia-Idade , Fatores de Risco , Adulto , Rejeição de Enxerto/etiologia , Seguimentos , Prognóstico , Medição de Risco
2.
J Org Chem ; 89(7): 4503-4511, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38502929

RESUMO

Tetrahydroisoquinoline (THIQ) derivatives stand out as a promising class of compounds due to their diverse range of biological activities, making them particularly valuable in drug discovery. To enhance their structural diversity, an Rh-catalyzed denitrogenative annulation method has been introduced for synthesizing these derivatives. An intriguing aspect of this method is the ability of the Brønsted acid to prevent further annulation while facilitating the production of the desired THIQ derivatives, achieving impressive yields of up to 86%. This synthetic approach was subsequently leveraged to create an analogue of cyclocelabenzine, a compound showing potential as an anti-inflammatory agent.

3.
Angew Chem Int Ed Engl ; 61(44): e202207824, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36082970

RESUMO

Oxidative N-heterocyclic carbene (NHC) organocatalysis, typically leading to the formation of acyl azolium reactive intermediates, constitutes one of the most important activation strategies for the NHC-catalyzed chemical transformations. Here, we report an unprecedented oxidative radical NHC catalysis by using peroxyester as the external single-electron oxidant to realize divergent difunctionalization of olefins. The key to success of this chemistry is the catalytic generation of oxygen radicals that could trigger an intermolecular hydrogen atom transfer to activate the inert C-H bonds, thereby enabling the productive radical relay process. With this protocol, commonly used general chemicals could serve as radical precursors to allow efficient synthesis of value-added products in a straightforward and cost-effective manner. Preliminary mechanistic investigations, including control experiments and DFT calculations, shed light on the NHC organocatalytic radical reaction mechanism.

4.
Chemistry ; 24(5): 1112-1120, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29044757

RESUMO

In this study, a series of variously substituted 2,3-dihydroquinolin-4-imines (DQIs) were synthesized from N-substituted propargylanilines by copper(I)-catalyzed annulation. The approach adopted in this study under mild, effective conditions exhibited broad substrate tolerance, particularly for functional groups substituted on anilines. Most of the DQI derivatives synthesized under optimal conditions were obtained in good isolated yields of 63-88 %. 2,3-Dihydroquinolinimine thus obtained was easily converted to important structures like 2,3-dihydroquinolone and tetrahydrobenzodiazepin-5-one, confirming the importance of this strategy in constructing various heterocycles. Surprisingly, 2,3-dihydroquinolinimines thus obtained exhibited bright fluorescence with quantum yields up to 66 %. The density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were performed for understanding the excited-state nature of DQI system. Accordingly, a tailored DQI derivative bearing methoxy group at C-6 position and acetoxy group at C-7 position was designed and synthesized to give emission at 559 nm with redshift compared to the 7-methoxy substituted DQI. A detailed study of DQI structures with their photophysical properties was performed with five control molecules and consequently demonstrated the uniqueness of the chemical structures of DQIs.

5.
Materials (Basel) ; 17(5)2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38473687

RESUMO

Solid oxide electrolysis cell (SOEC) industrialization has been developing for many years. Commercial materials such as 8 mol% Y2O3-stabilized zirconia (YSZ), Gd0.1Ce0.9O1.95 (GDC), La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF), La0.6Sr0.4CoO3-δ (LSC), etc., have been used for many years, but the problem of mismatched thermal expansion coefficients of various materials between cells has not been fundamentally solved, which affects the lifetime of SOECs and restricts their industry development. Currently, various solutions have been reported, such as element doping, manufacturing defects, and introducing negative thermal expansion coefficient materials. To promote the development of the SOEC industry, a direct treatment method for commercial materials-quenching and doping-is reported to achieve the controllable preparation of the thermal expansion coefficient of commercial materials. The quenching process only involves the micro-treatment of raw materials and does not have any negative impact on preparation processes such as powder slurry and sintering. It is a simple, low-cost, and universal research strategy to achieve the controllable preparation of the thermal expansion coefficient of the commercial material La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) through a quenching process by doping elements and increasing oxygen vacancies in the material. Commercial LSCF materials are heated to 800 °C in a muffle furnace, quickly removed, and cooled and quenched in 3.4 mol/L of prepared Y(NO3)3. The thermal expansion coefficient of the treated material can be reduced to 13.6 × 10-6 K-1, and the blank sample is 14.1 × 10-6 K-1. In the future, it may be possible to use the quenching process to select appropriate doping elements in order to achieve similar thermal expansion coefficients in SOECs.

6.
Chest ; 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39154796

RESUMO

BACKGROUND: Multiple listing (ML) is a practice used to increase the potential for transplant but is controversial due to concerns that it disproportionately benefits patients with greater access to health care resources. RESEARCH QUESTION: Is there disparity in ML practices based on social deprivation in the United States and does ML lead to quicker time to transplant? STUDY DESIGN AND METHODS: A retrospective cohort study of adult (≥ 18 years of age) lung transplant candidates listed for transplant (2005-2018) was conducted. Exclusion criteria included heart only or heart and lung transplant and patients relisted during the observation period. Data were obtained from the United Network for Organ Sharing Standard Transplant Analysis and Research File. The first exposure of interest was the Social Deprivation Index with a primary outcome of ML status, to assess disparities between ML and single listing (SL) participants. The second exposure of interest was ML status with a primary outcome of time to transplant, to assess whether implementation of ML leads to quicker time to transplant. RESULTS: A total of 35,890 patients were included in the final analysis, of whom 791 (2.2%) were ML and 35,099 (97.8%) were SL. ML participants had lower median level of social deprivation (5 units, more often female: 60.0% vs 42.3%) and lower median lung allocation score (35.3 vs 37.3). ML patients were more likely to be transplanted than SL patients (OR, 1.42; 95% CI, 1.17-1.73), but there was a significantly quicker time to transplant only for those whom ML was early (within 6 months of initial listing) (subdistribution hazard ratio, 1.17; 95% CI, 1.04-1.32). INTERPRETATION: ML is an uncommon practice with disparities existing between ML and SL patients based on several factors including social deprivation. ML patients are more likely to be transplanted, but only if they have ML status early in their transplant candidacy. With changing allocation guidelines, it is yet to be seen how ML will change with the implementation of continuous distribution.

7.
J Heart Lung Transplant ; 42(10): 1455-1463, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37290569

RESUMO

BACKGROUND: Lung transplant (LT) centers are increasingly evaluating patients with multiple risk factors for adverse outcomes. The effects of these stacked risks remains unclear. Our aim was to determine the relationship between the number of comorbidities and post-transplant outcomes. METHODS: We performed a retrospective cohort study using the National Inpatient Sample (NIS) and UNOS Starfile (USF). We applied a probabilistic matching algorithm using 7 variables (transplant: month, year, and type; recipient: age, sex, race, payer). We matched recipients in the USF to transplant patients in the NIS between 2016 and 2019. The Elixhauser methodology was used to identify comorbidities present on admission. We determined the associations between mortality, length of stay (LOS), total charges, and disposition with comorbidity numbers using penalized cubic splines, Kaplan-Meier, and linear and logistic regression methods. RESULTS: From 28,484,087 NIS admissions, we identified 1,821 LT recipients. Matches were exact in 76.8% of the cohort. While the remaining cohort had a probability match of ≥0.94. Penalized splines of Elixhauser comorbidity number identified 3 knots defining 3 groups of stacked risk: low (<3), medium (3-6), and high risk (>6). Inpatient mortality increased from low to medium to high-risk categories: (1.6%, 3.9%, and 7.0%; p < 0.001), as did LOS (16, 21, 29 days, p < 0.001), total charges ($553,057, $666,791, $821,641.5; p = 0.004) and discharge to a skilled nursing facility (15%, 20%, 31%; p < 0.001). CONCLUSIONS: Stacked risks adversely affect post-LT mortality, LOS, charges, and discharge disposition. Further study to understand the details of specific stacked risks is warranted.


Assuntos
Hospitalização , Alta do Paciente , Humanos , Estudos Retrospectivos , Tempo de Internação , Fatores de Risco
8.
Sci Bull (Beijing) ; 65(6): 452-459, 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36747434

RESUMO

Silicon is attracting considerable attention as an active anode material for advanced lithium-ion batteries due to its ultrahigh theoretical capacity. However, the reversible utilization of silicon-based anode materials is still hindered by the rapid capacity decay, as a consequence of the huge volume change of silicon during cycling. Herein, we use a Co-zeolitic imidazole framework (ZIF-67) to prepare silicon-wrapped nitrogen-doped carbon nanotubes (Si@N-doped CNTs) by controllable thermal pyrolysis. The as-prepared nanocomposites can effectively prevent pulverization and accommodate volume fluctuations of silicon during cycling. It can deliver a highly reversible capacity of 1100 mAh g-1 even after 750 cycles at a current density of 1000 mA g-1. As confirmed by an in situ transmission electron microscopy experiment, the remarkable electrochemical performance of Si@N-doped CNTs is attributed to the high electronic conductivity and flexibility of cross-linked N-doped CNTs network as a cushion to mitigate the mechanical stress and volume expansion. Furthermore, a full cell consisting of Si@N-doped CNTs anode and LiFePO4 cathode delivers a high reversible capacity of 1264 mAh g-1 and exhibits good cycling stability (>85% capacity retention) over 140 cycles at 1/4 C (1 C = 4000 mA g-1) rate.

9.
Sci Rep ; 7: 43059, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28220866

RESUMO

The aim of this study was to explore the associations and differences in influencing factors between alcoholic liver disease (ALD) coupled with Helicobacter pylori infection and atherosclerosis and to determine whether there is a "double hit phenomenon" in atherosclerosis patients with ALD and H. pylori infections. Included cases (n = 160) were categorized into 4 groups: 41 cases of ALD coupled with H. pylori infections (group A), 35 cases of H. pylori infections without ALD (group B), 37 cases of ALD without H. pylori infections (group C), and 47 normal control cases (group D). CIMT was significantly greater in group A than in groups B and D (P = 0.005 and P = 0.001, respectively). The GLM univariate analysis found that CIMT was significantly greater in group A than in groups B, C and D (P = 0.018, P = 0.001 and P = 0.009, respectively). We found that BMI and ALT, AST and ApoB levels were independent predictors of CIMT (P = 0.000, P = 0.000, P = 0.012 and P = 0.014, respectively). ALD coupled with H. pylori infection may result in significant CIMT thickening, but H. pylori infection without ALD and ALD without H. pylori infection does not, suggesting that a "double hit phenomenon" occurs. Additionally, BMI, and ALT, AST and ApoB levels were independent risk factors for increased CIMT.


Assuntos
Aterosclerose/etiologia , Infecções por Helicobacter/complicações , Helicobacter pylori , Hepatopatias Alcoólicas/complicações , Adulto , Aterosclerose/epidemiologia , Aterosclerose/patologia , Doenças das Artérias Carótidas/epidemiologia , Doenças das Artérias Carótidas/etiologia , Espessura Intima-Media Carotídea , Feminino , Infecções por Helicobacter/patologia , Humanos , Hepatopatias Alcoólicas/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
10.
Int J Biol Macromol ; 87: 555-62, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26993529

RESUMO

In our previous study, a polysaccharide was extracted from Schisandra Chinensis (Trucz.) Baill and found with anti-diabetic effects. The aim of this study was to investigate the anti-diabetic effects of the low weight molecular polysaccharide (SCPP11) purified from crude Schisandra polysaccharide and illustrate the underlying mechanism in buffalo rat liver cells. The insulin resistance model of BRL cells was established by incubating with insulin solution for 24h. The effects of SCPP11 on regulating related protein and mRNA expression in an insulin and AMPK signal pathway were investigated by western blot and RT-PCR analysis. SCPP11 showed no cytotoxicity to BRL cells and could improve the glucose consumption in BRL cells. SCPP11 increased the protein expression of Akt, p-AMPK and GLUT-4 in BRL cells. Moreover, SCPP11 could enhance the mRNA expression levels of IRS-1, PI3K, Akt, GLUT-4, AMPKα and PPAR-γ in BRL cells at the same time. In conclusion, SCPP11 possessed effects in improving glucose consumption by up-regulating the expression of GLUT-4 which might occur via insulin and AMPK signal pathway and could be a potential functional food to prevent and mitigate the insulin resistance condition.


Assuntos
Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Hipoglicemiantes/farmacologia , Polissacarídeos/farmacologia , Schisandra/química , Regulação para Cima/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Linhagem Celular , Insulina/metabolismo , Resistência à Insulina , PPAR gama/genética , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos
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