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1.
Catheter Cardiovasc Interv ; 101(1): 209-216, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36478105

RESUMO

BACKGROUND: Post-infarction ventricular septal defect (PIVSD) carries a very poor prognosis. Surgical repair offers reasonable outcomes in patients who survive the initial healing period. Percutaneous device implantation remains a potentially effective earlier alternative. METHODS AND RESULTS: From March 2018 to May 2022, 11 trans-arterial PIVSD closures were attempted in 9 patients from two centers (aged 67.2 ± 11.1 years; 77.8% male). Two patients had a second procedure. Myocardial infarction was anterior in four patients (44.5%) and inferior in five cases (55.5%). Devices were successfully implanted in all patients. There were no major immediate procedural complications. Immediate shunt grade postprocedure was significant (11.1%), minimal (77.8%), or none (11.1%). Median length of stay after the procedure was 14.8 days. Five patients (55%) survived to discharge and were followed up for a median of 605 days, during which time no additional patients died. CONCLUSION: Single arterial access for percutaneous closure of PIVSD is a good option for these extremely high-risk patients, in the era of effective large-bore arterial access closure. Mortality remains high, but patients who survive to discharge do well in the longer term.


Assuntos
Infarto Miocárdico de Parede Anterior , Procedimentos Cirúrgicos Cardíacos , Comunicação Interventricular , Infarto do Miocárdio , Dispositivo para Oclusão Septal , Humanos , Masculino , Feminino , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Resultado do Tratamento , Cateterismo Cardíaco/efeitos adversos , Cateterismo Cardíaco/métodos , Comunicação Interventricular/cirurgia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/terapia , Infarto Miocárdico de Parede Anterior/complicações , Dispositivo para Oclusão Septal/efeitos adversos
2.
J Org Chem ; 88(9): 5254-5274, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37083424

RESUMO

The first diastereo- and enantiodivergent asymmetric synthesis of new bis-spirocyclopropyloxindole scaffolds has been accomplished from the readily available isatin as a single starting material. Four rel-(1R,2R,3R), rel-(1S,2S,3R), rel-(1R,2R,3S), and rel-(1S,2S,3S) configurations of desired products were constructed in excellent enantiopurity via a simple switch in substrates using the chiral auxiliary-controlled method. The absolute configuration of cycloadducts with three contiguous quaternary/tertiary stereogenic centers was confirmed through X-ray diffraction analysis. A facile synthesis of versatile precursor 3-chlorooxindoles was also introduced.

3.
Org Biomol Chem ; 21(10): 2143-2161, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36799076

RESUMO

In the present study, a library of important enantiopure dispirooxindole [indolizidine, pyrrolizidine, and pyrrolidine] derivatives with three or four contiguous and two quaternary stereogenic centers using different amino acids (pipecolic acid, sarcosine, proline and hydroxyproline) were synthesized in high yields (up to 96%) through a regio- and diastereoselective (up to 99 : 1) multicomponent 1,3-dipolar cycloaddition strategy. Based on the results, the alteration of amino acids led to a change in the regioselectivity and unusual regioisomers (pyrrolizidine versus indolizidine/pyrrolidine) were obtained to construct a novel enantiopure 1,3-dispirooxindole skeleton. The stereochemical outcome of the cycloaddition was determined by single crystal X-ray diffraction analysis and the self-disproportionation of enantiomers (SDE) test confirmed the enantiomeric purity of the desired products. The mechanism and differences in the regioselectivity of the 1,3-dipolar cycloaddition reactions between the stable azomethane ylides obtained from ninhydrin, pipecolinic acid, and proline with (E)-2-oxoindolin-3-ylideneacetyl sultam were theoretically studied through DFT calculations at the M06-2X/6-31G(d,p) level in methanol.

4.
J Card Surg ; 37(12): 4598-4605, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36284463

RESUMO

INTRODUCTION: In mitral valve replacement (MVR), sudden increases in afterload and disruption of the annular-chordal-papillary-left-ventricular wall causes left ventricular (LV) dysfunction in the early postoperative period. Preservation of the posterior mitral leaflet apparatus (MVR-P) has a favorable outcome on LV function. However, there is paucity of data on the impact of complete preservation of the sub-valvular apparatus (MVR-C). OBJECTIVE: We investigated the impact of MVR-P and MVR-C on baseline and 3-months postoperative LV ejection fraction (EF) and global longitudinal strain (GLS). METHODS: We retrospectively analyzed a cohort of 29 MVR-P and 19 MVR-C patients with complete echocardiography data at our unit, who were operated between 2008 and 2017. Between-group changes in LVEF and GLS were compared using independent sample T-test. RESULTS: Median age was 59 years (IQR 50-69 years). Baseline LVEF was 58% (51%- 60%). Baseline GLS was -18.4 (-21.2 to -15.5). There were no significant between-group differences between all baseline demographics and echocardiographic markers. There was significantly higher absolute postoperative LVEF in MVR-C patients (p = 0.029). There was also significant worsening in LVEF (p = 0.0121) and GLS (p < 0.0001) after MVR-P and not MVR-C, suggesting no reduction in LV function post-MVR-C but a reduction post-MVR-P. There was significantly less postoperative worsening of GLS per patient in MVR-C group as compared to the MVR-P group (p = 0.023), indicating better preservation of LV function. There was also a smaller decline in LVEF per patient in the MVR-C as compared to the MVR-P group, although not statistically significant (p = 0.23). CONCLUSION: MVR with complete preservation of the sub-valvular apparatus shows a favorable impact on the longitudinal function of the heart at 3 months. Further studies with larger patient numbers are indicated to investigate the long-term results of this surgical approach.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Disfunção Ventricular Esquerda , Humanos , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Função Ventricular Esquerda , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Insuficiência da Valva Mitral/complicações , Estudos Retrospectivos , Volume Sistólico , Disfunção Ventricular Esquerda/etiologia , Implante de Prótese de Valva Cardíaca/métodos
5.
Exp Mol Pathol ; 123: 104703, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34619140

RESUMO

BACKGROUND AND AIM: Parkinson's disease (PD) is a progressive neurodegenerative disorder caused by the destruction of the dopaminergic neurons in the nigrostriatal pathway, leading to motor-behavioral complications. Cell therapy has been proposed as a promising approach for PD treatment using various cellular sources. Despite a few disadvantages mesenchymal stem cells (MSCs) represent, they have more auspicious effects for PD cell therapy. The present study aimed to evaluate a new source of MSCs isolated from human Conjunctiva (CJ-MSCs) impact on PD complications for the first time. MATERIALS AND METHODS: Parkinson's was induced by stereotactic injection of 6-hydroxydopamine (6-OHDA) into the right medial forebrain bundle (MFB). An apomorphine-induced rotation test was used to confirm the model establishment. After PD model confirmation, green fluorescent protein (GFP) labeled CJ-MSCs and induced CJ-MSCs (microfluidic encapsulated and non-capsulated) were transplanted into the rats' right striatum. Then Rotation, Rotarod, and Open-field tests were performed to evaluate the behavioral assessment. Additionally, the immunohistochemistry technique was used for identifying tyrosine hydroxylase (TH). RESULTS: According to the obtained data, the cell transplantation caused a reduction in the rats' rotation number and improved locomotion compared to the control group. The previous results were also more pronounced in induced and microfluidic encapsulated cells compared to other cells. Rats recipient CJ-MSCs also have represented more TH-expressed GFP-labeled cell numbers in the striatum than the control group. CONCLUSION: It can be concluded that CJ-MSCs therapy can have protective effects against PD complications and nerve induction of cells due to their ability to express dopamine. On the other hand, CJ-MSCs microencapsulating leads to enhance even more protective effect of CJ-MSCs. However, confirmation of this hypothesis requires further studies and investigation of these cells' possible mechanisms of action.


Assuntos
Túnica Conjuntiva/transplante , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Doença de Parkinson/terapia , Animais , Túnica Conjuntiva/citologia , Corpo Estriado/patologia , Corpo Estriado/transplante , Modelos Animais de Doenças , Humanos , Técnicas Analíticas Microfluídicas , Oxidopamina/farmacologia , Doença de Parkinson/patologia , Ratos
6.
Metab Brain Dis ; 36(7): 2089-2100, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34357552

RESUMO

Parkinson's disease (PD) is a complex neurodegenerative disease in which the understanding of the underlying molecular mechanisms can be constructive in the diagnosis and treatment. Matrix metalloproteinase (MMPs) elevation and damage to the blood-brain barrier (BBB) are critical mechanisms involved in the PD separation. Studies have revealed that changes in miR-149-5p and CoQ10 are associated with BBB damage, and CoQ10 can affect the levels of some miRs. Hence, in the present study, we aimed to evaluate CoQ10 and miR-149-5p mimic on miR-149-5p, MMPs and TH expression, and behavioral functions of the PD models. PD was induced by injection of 6-OHDA into the rats' Medial Forbrain Bundle (MFB). The behavioral tests, including the Rotation test, Rotarod test, and Open field test, have been directed two weeks after PD induction. Next, the MiR-149-5p mimic (miR-mimic) and CoQ10 have been administered to rats. The same behavioral tests have been evaluated two weeks after administration to investigate the effect of miR-149-5p mimic and CoQ10. The rats were followed extra four weeks, and the behavioral tests have performed again. Finally, the expression of MMPs and miR-149-5p genes was measured using RT-qPCR, and tyrosine hydroxylase (TH) was assessed through immunohistochemistry analysis. According to the obtained results, the level of miR-149-5p has decreased, followed by PD induction in rats. RT-qPCR analysis has represented upregulation and downregulation of miR-149-5p and MMP-2,9, respectively, after miR-mimic and CoQ10 treatment. The treated rats have also represented improved motor function and increased TH + cells in the striatum according to the behavioral tests and immunohistochemistry assay. Taking together miR-149 and CoQ10 has shown to have an impressive potential to prevent damage to dopaminergic neurons caused by 6-OHDA injection through reducing MMP-2,9, increased TH expression, and improved motor function.


Assuntos
MicroRNAs , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Doença de Parkinson , Animais , Modelos Animais de Doenças , Metaloproteinases da Matriz/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Oxidopamina , Doença de Parkinson/tratamento farmacológico , Ratos , Ubiquinona/análogos & derivados
7.
Nanotechnology ; 31(46): 465405, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-32721931

RESUMO

In this paper, coupled optical and electrical simulations of perovskite solar cells (PSCs) are performed to optimize their basis output parameters and obtain the best power conversion efficiency (PCE) based on both the light absorption and carrier transport mechanisms. Due to the limitations of perovskite absorption in longer wavelengths, we used an extra photo-active material of GeSe with a narrower bandgap and a broader absorbing spectrum to increase the efficiency of the PSC. To prevent carrier transmission disorder that exists in the planar structure with two absorbing materials, GeSe was inserted into the main active layer in the form of nanowires (NWs). As a result, it improved the carrier transfer and open-circuit voltage (Voc ) in addition to the short-circuit current density (Jsc ). The behavior of PSC with different sizes of GeSe NWs at the same density was investigated to determine the appropriate size of NWs and achieve the highest PCE. In the optimal structure with 50 nm diameter NWs, Jsc and PCE of the cell are 22.96 mA cm-2 and 18.97%, which are improvements of 39% and 50%, respectively, compared to the planar structure studied at the beginning of the paper.

8.
Heart Lung Circ ; 28(4): e59-e63, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30017633

RESUMO

Aortic paravalvular leakage (PVL) is a recognised complication of surgically replaced valves which is often treated using vascular plugs. Whilst transcatheter valve-in-valve therapy has been increasingly used for failed surgical bioprostheses, it is not considered as a treatment option for aortic PVL. However, the newer design of transcatheter aortic valves has a fabric skirt to create a more effective seal around the annulus. To our best knowledge, for the first time, we report successful adoption of the valve-in-valve therapy for the treatment of PVL in surgical bioprosthetic aortic valves such that the fabric skirt is placed immediately below the regurgitant orifice resulting in significant reduction in the PVL.


Assuntos
Insuficiência da Valva Aórtica/cirurgia , Valva Aórtica/cirurgia , Valvuloplastia com Balão/métodos , Bioprótese/efeitos adversos , Cateterismo Cardíaco/métodos , Próteses Valvulares Cardíacas/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Idoso , Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/diagnóstico , Ecocardiografia Doppler em Cores , Ecocardiografia Tridimensional , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Desenho de Prótese , Falha de Prótese , Reoperação
9.
Int Ophthalmol ; 39(7): 1467-1474, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29934932

RESUMO

PURPOSE: To measure IOP in animals, it is often necessary to use topical anesthetics. The use of these drugs may cause changes in IOP and interfere with the final results. To address this issue, the effects of four local anesthetics (tetracaine, proparacaine, lidocaine, and bupivacaine) on IOP were investigated in ten adult dogs. METHODS: One drop of tetracaine was instilled in the right eye of half of the dogs and in the left eye of the other dogs; normal saline was instilled in the fellow eyes. The IOP in each dog was measured before and at 0, 5, 10, 15, 20, 25, 30, and 35 min after drug instillation using an electronic rebound tonometer. The effects of the other anesthetics were studied in the same way at intervals of at least 1 week. RESULTS: After instillation of tetracaine, the IOP decreased gradually, such that after 15 min, the IOP was significantly lower than the baseline (p = 0.022) and control values (p = 0.048). Proparacaine also reduced IOP after 10 min compared to baseline values (p = 0.046), but the two other drugs, bupivacaine and lidocaine, had no significant effect on IOP. The duration of eye anesthesia was 16, 20, 22, and 34 min for tetracaine, lidocaine, bupivacaine, and proparacaine, respectively. CONCLUSION: We recommend using drugs that combine inducing longer anesthesia with producing the smallest change in IOP, such as bupivacaine and, subsequently, lidocaine. Tetracaine and proparacaine have a significant effect on IOP, and if these drugs are used, this effect should be considered.


Assuntos
Anestesia Local/métodos , Bupivacaína/administração & dosagem , Glaucoma/prevenção & controle , Pressão Intraocular/efeitos dos fármacos , Lidocaína/administração & dosagem , Propoxicaína/administração & dosagem , Tetracaína/administração & dosagem , Administração Tópica , Anestésicos Locais/administração & dosagem , Animais , Modelos Animais de Doenças , Cães , Feminino , Glaucoma/etiologia , Glaucoma/fisiopatologia , Masculino
10.
Nanotechnology ; 29(20): 205201, 2018 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-29473826

RESUMO

In this work MoS2 thin film was studied as a potential two-dimensional (2D) hole-transporting material for fabrication of low-cost, durable and efficient perovskite solar cells. The thickness of MoS2 was studied as a potential factor in reaching high power conversion efficiency in perovskite solar cells. The thickness of the perovskite layer and the different metal back contacts gave distinct photovoltaic properties to the designed cells. The results show that a single sheet of MoS2 could considerably improve the power conversion efficacy of the device from 10.41% for a hole transport material (HTM)-free device to 20.43% for a device prepared with a 0.67 nm thick MoS2 layer as a HTM. On the back, Ag and Al collected the carriers more efficiently than Au due to the value of their metal contact work function with the TiO2 conduction band. The present work proposes a new architecture for the fabrication of low-cost, durable and efficient perovskite solar cells made from a low-cost and robust inorganic HTM and electron transport material.

11.
Biologicals ; 50: 49-54, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28942114

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder of the brain which is produced by the damage to dopaminergic neurons. Stem cell transplantation with a nanofibrous scaffold is one of the encouraging strategies for Parkinson's disease therapy. In this study, human mesenchymal stem cells (MSCs) from eye trabecular meshwork (TM) were differentiated into dopaminergic neurons on nanofibrous scaffold. After Trabecular meshwork biopsy, MSCs were isolated, cultivated on Poly-l-Lactide Acid (PLLA) nanofibrous scaffold (fabricated by electrospinning methods) and treated with medium containing DMEM supplemented with RA, IBMX and forskolin for 7 days. Scanning electron microscopy imaging, qPCR and immunostaining were used to analyze differentiated TM-MSCs on scaffold and their expression of dopaminergic-specific markers such as TH and Nurr-1. qPCR analysis revealed the expression of dopaminergic neuron genes such as TH, Nurr-1 on fibrous scaffold as well as TCPS. Immunostaining revealed that the differentiated TM-MSCs on TCPS and Scaffold not only express TH and Nurr-1 genes, but also express TH protein. In conclusion, the results indicate that TM-MSCs might be a suitable source for cell transplantation therapy. In addition the nanofibrous scaffold reported herein could be used as a potential cell carrier for the central system diseases such as PD.


Assuntos
Diferenciação Celular , Neurônios Dopaminérgicos/citologia , Células-Tronco Mesenquimais/citologia , Malha Trabecular/citologia , Técnicas de Cultura de Células/métodos , Células Cultivadas , Neurônios Dopaminérgicos/metabolismo , Expressão Gênica , Humanos , Células-Tronco Mesenquimais/metabolismo , Microscopia Eletrônica de Varredura , Nanofibras/química , Nanofibras/ultraestrutura , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Poliésteres/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Malha Trabecular/metabolismo , Malha Trabecular/ultraestrutura
12.
Heart Lung Circ ; 26(11): e71-e75, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28511922

RESUMO

Repeat cardiac surgery in patients with a previous sternotomy is associated with significant morbidity and mortality. While transcatheter aortic valve implantation in high risk surgical patients is now well established, experience with transcatheter mitral valve replacement is still at an early stage. Although many successful reports of transcatheter mitral valve replacements now exist, the predominant approach has been via a transapical approach. It is likely that, as with the evolution of favoured access routes for transcatheter aortic therapies, future directions for transcatheter mitral valves will focus on smaller delivery systems favouring the transvenous transseptal approach where possible. We present the first reported case of combined transseptal para-ring leak closure followed by transcatheter mitral valve implantation using a 12/5mm Amplatzer III vascular plug and a 29mm SAPIEN 3 valve.


Assuntos
Fístula Anastomótica/cirurgia , Valva Mitral/cirurgia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Fístula Anastomótica/etiologia , Humanos , Masculino , Pessoa de Meia-Idade
13.
J Card Fail ; 21(5): 374-381, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25724302

RESUMO

BACKGROUND: Selecting heart failure (HF) patients for intensive management to reduce readmissions requires effective targeting. However, available prediction scores are only modestly effective. We sought to develop a prediction score for 30-day all-cause rehospitalization or death in HF with the use of nonclinical and clinical data. METHODS AND RESULTS: This statewide data linkage included all patients who survived their 1st HF admission (with either reduced or preserved ejection fraction) to a Tasmanian public hospital during 2009-2012. Nonclinical data (n = 1,537; 49.5% men, median age 80 y) included administrative, socioeconomic, and geomapping data. Clinical data before discharge were available from 977 patients. Prediction models were developed and internally and externally validated. Within 30 days of discharge, 390 patients (25.4%) died or were rehospitalized. The nonclinical model (length of hospital stay, age, living alone, discharge during winter, remoteness index, comorbidities, and sex) had fair discrimination (C-statistic 0.66 [95% confidence interval (CI) 0.63-0.69]). Clinical data (blood urea nitrogen, New York Heart Association functional class, albumin, heart rate, respiratory rate, diuretic use, angiotensin-converting enzyme inhibitor use, arrhythmia, and troponin) provided better discrimination (C-statistic 0.72 [95% CI 0.68-0.76]). Combining both data sources best predicted 30-day rehospitalization or death (C-statistic 0.76 [95% CI 0.72-0.80]). CONCLUSIONS: Clinical data are stronger predictors than nonclinical data, but combining both best predicts 30-day rehospitalization or death among HF patients.


Assuntos
Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/mortalidade , Armazenamento e Recuperação da Informação/tendências , Readmissão do Paciente/tendências , Idoso , Idoso de 80 Anos ou mais , Feminino , Insuficiência Cardíaca/terapia , Humanos , Masculino , Mortalidade/tendências , Valor Preditivo dos Testes , Tasmânia/epidemiologia , Fatores de Tempo
14.
Cell Mol Neurobiol ; 34(3): 343-50, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24326522

RESUMO

Cognitive dysfunction occurs in patients with diabetes mellitus. The objective of this study was to examine whether bilateral intrahippocampal CA1 (intra-CA1) injection of aminoguanidine (AG) can either affect the Bcl-2 family gene expression or reduce the diabetic imposing abnormalities of passive avoidance learning (PAL) and memory. Rats were divided into five groups: control (C), control treated with normal saline (CS), control treated with AG (S-AG), diabetics (D), and diabetics treated with AG (D-AG). Diabetes mellitus was induced by a single intraperitoneal injection of streptozotocin (STZ) (50 mg/kg). AG (30 µg/rat) or vehicle was administered intra-CA1 bilaterally at the onset of hyperglycemia. PAL was assessed 7 weeks later. Animals were killed, and hippocampus was dissected following the behavioral test. The expressions of Bax, Bcl-2, and Bcl-xl mRNAs were measured using semiquantitative RT-PCR technique. The result of passive avoidance task showed that AG significantly improved the cognitive performance in diabetic rats. Moreover, AG treatment decreased the levels of Bcl-2 and Bcl-xL expressions in diabetic group. The ratio of Bax/Bcl-2 and Bax/Bcl-xL decreased significantly in AG-treated diabetic animals. In conclusion, initial treatment with AG by intra-CA1 micro-injection improves the impaired passive avoidance task in STZ-induced diabetic rats which may be related to the decreased Bax/Bcl-2 and Bax/Bcl-xL ratios.


Assuntos
Aprendizagem da Esquiva/fisiologia , Diabetes Mellitus Experimental/metabolismo , Guanidinas/uso terapêutico , Memória/fisiologia , Proteína X Associada a bcl-2/biossíntese , Proteína bcl-X/biossíntese , Animais , Proteínas Reguladoras de Apoptose/biossíntese , Aprendizagem da Esquiva/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Regulação da Expressão Gênica , Guanidinas/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Memória/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Distribuição Aleatória , Ratos , Ratos Wistar
15.
Sci Rep ; 14(1): 5500, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38448629

RESUMO

The external quantum efficiency (EQE) of a perovskite-based light-emitting diode (PELED) is a key indicator, comprising the internal quantum efficiency (IQE) and light extraction efficiency (LEE). Currently, enhancing EQE faces a major challenge in optimizing LEE. This study introduces an innovative structure to boost LEE, exploring various influencing parameters. The transition from a planar to a domical architecture leverages factors like the waveguiding effect, resulting in a remarkable tenfold increase in LEE, from 6 to 59%. Additionally, investigations into factors affecting LEE, such as altering dipole orientation, material-substrate contact angle, and layer thickness, reveal the potential for further improvement. The optimized structure attains an impressive LEE value of 74%.

16.
Heliyon ; 10(15): e35264, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39161815

RESUMO

Hydrogels containing antimicrobial materials have emerged as attractive platforms for wound treatment in the past decade due to their favorable bio-mimicking properties, excellent modulation of bacterial infection, and ability to minimize bacterial resistance. Herein, a hybrid combination of polyvinyl alcohol (PVA), hyperbranched poly L-lysine (L), tannic acid decorated AgNPs (AgTA NPs), loaded with Allantoin (Alla) is used to fabricate PLAg-Alla hydrogel dressing via the freeze-thaw method without use of any chemical cross-linker. The PLAg-Alla hydrogel possesses a great structure, is biodegradable, and safe, and exhibits high antibacterial potential, all required for efficient wound healing. The incorporation of AgTA and poly L-lysine (L) within the hydrogel contributes to the enhancement of antibacterial ability, as well as effectively promoting the wound healing. This hybrid hydrogel possessed favorable physicochemical features, robust antibacterial properties, and accelerated wound healing in vivo as promising dressing for the clinical application.

17.
Am J Cardiol ; 222: 23-28, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692400

RESUMO

The Navitor transcatheter heart valve (THV) is the latest iteration of the Portico self-expanding valve system. Early prospective studies have shown promising outcomes, however, there is a lack of complementary 'real-world' data. This study aimed to assess early safety and efficacy outcomes of the Navitor THV using registry data from 6 high-volume United Kingdom transcatheter aortic valve replacement (TAVR) centers. Demographic, procedural, and in-hospital outcome data were retrieved from 6 United Kingdom centers. The primary safety end point was 30-day mortality. Primary efficacy end points were procedural success, mean aortic gradient, and ≥moderate paravalvular leak. Secondary end points included rates of new permanent pacemaker implantation, stroke, and vascular injury. A total of 574 patients (mean age 83.4 years; 54.5% female) underwent Navitor TAVR between January 2020 and May 2023. The 30-day mortality in this patient cohort was 1.6%. Procedural success was 98.1%, mean echo-derived gradient post-TAVR was 7.7 ± 4.8 mm Hg (95% confidence interval [CI] 7.2 to 8.3, p <0.001) and 5.1% of patients had ≥moderate paravalvular leak (sample proportion estimate [p̂] = 0.051, 95% CI [0.035, 0.073], p <0.001). New permanent pacemaker implantation to discharge was required in 11% (p̂ = 0.119, 95% CI 0.088 to 0.158, p <0.001), stroke occurred in 1.2% of patients (p̂ = 0.017, 95% CI 0.006 to 0.036, p <0.001) and significant vascular injury in 1.6% (p̂ = 0.014, 95% CI 0.005 to 0.032, p <0.001). In conclusion, early procedural outcomes with Navitor TAVR compare favorably to new-generation THVs. Procedural success was high with a low incidence of complications.


Assuntos
Estenose da Valva Aórtica , Próteses Valvulares Cardíacas , Sistema de Registros , Substituição da Valva Aórtica Transcateter , Humanos , Substituição da Valva Aórtica Transcateter/métodos , Feminino , Masculino , Reino Unido/epidemiologia , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/cirurgia , Desenho de Prótese , Idoso , Complicações Pós-Operatórias/epidemiologia , Resultado do Tratamento , Valva Aórtica/cirurgia
18.
Micromachines (Basel) ; 14(9)2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37763894

RESUMO

In this research study, the effects of different parameters on the electron transfer rate from three quantum dots (QDs), CdSe, CdS, and CdTe, on three metal oxides (MOs), TiO2, SnO2, and SnO2, in quantum-dot-sensitized solar cells (QDSSCs) with porous structures in the presence of four types of blocking layers, ZnS, ZnO, TiO2, and Al2O3, are modeled and simulated using the Marcus theory and tunneling between two spheres for the first time. Here, the studied parameters include the change in the type and thickness of the blocking layer, the diameter of the QD, and the temperature effect. To model the effect of the blocking layer on the QD, the effective sphere method is used, and by applying it into the Marcus theory equation and the tunneling method, the electron transfer rate is calculated and analyzed. The obtained results in a wide range of temperatures of 250-400 °K demonstrate that, based on the composition of the MO-QD, the increase in the temperature could reduce or increase the electron transfer rate, and the change in the QD diameter could exacerbate the effects of the temperature. In addition, the results show which type and thickness of the blocking layer can achieve the highest electron transfer rate. In order to test the accuracy of the simulation method, we calculate the electron transfer rate in the presence of a blocking layer for a reported sample of a QDSSC manufacturing work, which was obtained with an error of ~3%. The results can be used to better interpret the experimental observations and to assist with the design and selection of the appropriate combination of MO-QD in the presence of a blocking layer effect.

19.
Sci Rep ; 13(1): 15905, 2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37741943

RESUMO

So far, remarkable achievements have been obtained by optimizing the device architecture and modeling of solar cells is a precious and very effective way to comprehend a better description of the physical mechanisms in solar cells. As a result, this study has inspected two-dimensional simulation of perovskite solar cells (PSCs) to achieve a precise model. The solution which has been employed is based on the finite element method (FEM). First, the periodically light trapping (LT) structure has been replaced with a planar structure. Due to that, the power conversion efficiency (PCE) of PSC was obtained at 14.85%. Then, the effect of adding an SiO2 layer to the LT structure as an anti-reflector layer was investigated. Moreover, increasing the PCE of these types of solar cells, a new structure including a layer of CH3NH3SnI3 as an absorber layer was added to the structure of PSCs in this study, which resulted in 25.63 mA/cm2 short circuit current (Jsc), 0.96 V open circuit voltage (Voc), and 20.48% PCE.

20.
Sci Rep ; 13(1): 18584, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37903845

RESUMO

The light absorption process is a key factor in improving the performance of perovskite solar cells (PSCs). Using arrays of metal nanostructures on semiconductors such as perovskite (CH3NH3PbI3), the amount of light absorption in these layers is significantly increased. Metal nanostructures have been considered for their ability to excite plasmons (collective oscillations of free electrons). Noble metal nanoparticles placed inside solar cells, by increasing the scattering of the incident light, effectively increase the optical absorption inside PSCs; this in turn increases the electric current generated in the photovoltaic device. In this work, by calculating the cross-sectional area of dispersion and absorption on gold (Au) nanoparticles, the effects of the position of nanoparticles in the active layer (AL) and their morphology on the increase of absorption within the PSC are investigated. The optimal position of the plasmonic nanoparticle was obtained in the middle of the AL using a three-dimensional simulation method. Then, three different morphologies of nano-sphere, nano-star and nano-cubes were investigated, where the short-circuit currents (Jsc) for these three nanostructures were obtained equal to 19.01, 18.66 and 20.03 mA/cm2, respectively. In our study, the best morphology of the nanostructure according to the Jsc value was related to the nano-cube, in which the device power conversion efficiency was equal to 16.20%, which is about 15% better than the PSC with the planar architecture.

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