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1.
J Am Chem Soc ; 146(14): 9623-9630, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38533830

RESUMO

The fundamental understanding of sluggish hydrogen evolution reaction (HER) kinetics on a platinum (Pt) surface in alkaline media is a topic of considerable debate. Herein, we combine cyclic voltammetry (CV) and electrical transport spectroscopy (ETS) approaches to probe the Pt surface at different pH values and develop molecular-level insights into the pH-dependent HER kinetics in alkaline media. The change in HER Tafel slope from ∼110 mV/decade in pH 7-10 to ∼53 mV/decade in pH 11-13 suggests considerably enhanced kinetics at higher pH. The ETS studies reveal a similar pH-dependent switch in the ETS conductance signal at around pH 10, suggesting a notable change of surface adsorbates. Fixed-potential calculations and chemical bonding analysis suggest that this switch is attributed to a change in interfacial water orientation, shifting from primarily an O-down configuration below pH 10 to a H-down configuration above pH 10. This reorientation weakens the O-H bond in the interfacial water molecules and modifies the reaction pathway, leading to considerably accelerated HER kinetics at higher pH. Our integrated studies provide an unprecedented molecular-level understanding of the nontrivial pH-dependent HER kinetics in alkaline media.

2.
Anim Biotechnol ; 34(8): 3908-3919, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37493347

RESUMO

This study was designed to isolate, cultivate, characterize and evaluate the growth kinetics of mesenchymal stem cells (MSCs) derived from fetal adnexa of sheep. The gravid uteri of ewes were collected from a local abattoir. The MSCs isolated from different fetal regions (Wharton's Jelly [oWJ], cord blood [oCB], amniotic fluid [oAF] and amniotic Sac [oAS]) were expanded in vitro and characterized for surface and pluripotency markers. The growth kinetics of MSCs was compared at 3rd and 5th passages. Similarly, the colony-forming efficiency (CFE) assay was performed at 3rd passage. The fetal adnexa-derived ovine MSCs showed the expression of CD73, CD90 and CD105. Similarly, the MSCs also expressed pluripotency markers, OCT4 and SOX2. Besides, cells also differentiated into osteogenic, chondrogenic and adipogenic lineages. The MSCs in culture showed a typical growth curve with initial lag phase, an exponential phase, a plateau phase and a decline phase. The growth rate was highest in oAF-MSCs at P5. The population doubling time (PDT) was highest in oAS-MSCs (87.28 ± 3.24 h), whereas the colony number was highest in oAF-MSCs (53.67 ± 4.06). The study reveals that oAF-MSCs were superior which outperformed other MSCs indicating that oAF-derived MSCs could be utilized for regenerative medicine.


Assuntos
Células-Tronco Mesenquimais , Geleia de Wharton , Animais , Ovinos , Feminino , Proliferação de Células , Diferenciação Celular , Geleia de Wharton/metabolismo , Adipogenia , Células Cultivadas
3.
Nat Mater ; 22(8): 1022-1029, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37349398

RESUMO

In analogy to natural enzymes, an elaborated design of catalytic systems with a specifically tailored local chemical environment could substantially improve reaction kinetics, effectively combat catalyst poisoning effect and boost catalyst lifetime under unfavourable reaction conditions. Here we report a unique design of 'Ni(OH)2-clothed Pt-tetrapods' with an amorphous Ni(OH)2 shell as a water dissociation catalyst and a proton conductive encapsulation layer to isolate the Pt core from bulk alkaline electrolyte while ensuring efficient proton supply to the active Pt sites. This design creates a favourable local chemical environment to result in acidic-like hydrogen evolution reaction kinetics with a lowest Tafel slope of 27 mV per decade and a record-high specific activity and mass activity in alkaline electrolyte. The proton conductive Ni(OH)2 shell can also effectively reject impurity ions and retard the Oswald ripening, endowing a high tolerance to solution impurities and exceptional long-term durability that is difficult to achieve in the naked Pt catalysts. The markedly improved hydrogen evolution reaction activity and durability in an alkaline medium promise an attractive catalyst material for alkaline water electrolysers and renewable chemical fuel generation.

4.
Nano Lett ; 23(7): 2758-2763, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36971471

RESUMO

Periodic assembly of heterogeneous nanoparticles provides a strategy for integrating distinct nanocatalyst blocks where their synergic effects can be explored for diverse applications. To achieve the synergistic enhancement, an intimate clean interface is preferred which however is usually plagued by the bulky surfactant molecules used in the synthesis and assembly process. Herein, we showed the creation of one-dimensional Pt-Au nanowires (NWs) with periodic alternating Pt and Au nanoblocks, by assembling Pt-Au Janus nanoparticles with the assistance of peptide T7 (Ac-TLTTLTN-CONH2). It is demonstrated that the Pt-Au NWs showed much-improved performance in the methanol oxidation reaction (MOR), exhibiting 5.3 times higher specific activity and 2.5 times higher mass activity than the current state-of-the-art commercial Pt/C catalyst. In addition, the periodic heterostructure also improves the stability of Pt-Au NWs in the MOR, where the Pt-Au NWs retained 93.9% of their initial mass activity much higher than commercial Pt/C (30.6%).

5.
Proc Natl Acad Sci U S A ; 119(39): e2208187119, 2022 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-36122216

RESUMO

Electrocatalytic hydrogen evolution reaction (HER) is critical for green hydrogen generation and exhibits distinct pH-dependent kinetics that have been elusive to understand. A molecular-level understanding of the electrochemical interfaces is essential for developing more efficient electrochemical processes. Here we exploit an exclusively surface-specific electrical transport spectroscopy (ETS) approach to probe the Pt-surface water protonation status and experimentally determine the surface hydronium pKa [Formula: see text] 4.3. Quantum mechanics (QM) and reactive dynamics using a reactive force field (ReaxFF) molecular dynamics (RMD) calculations confirm the enrichment of hydroniums (H3O[Formula: see text]) near Pt surface and predict a surface hydronium pKa of 2.5 to 4.4, corroborating the experimental results. Importantly, the observed Pt-surface hydronium pKa correlates well with the pH-dependent HER kinetics, with the protonated surface state at lower pH favoring fast Tafel kinetics with a Tafel slope of 30 mV per decade and the deprotonated surface state at higher pH following Volmer-step limited kinetics with a much higher Tafel slope of 120 mV per decade, offering a robust and precise interpretation of the pH-dependent HER kinetics. These insights may help design improved electrocatalysts for renewable energy conversion.


Assuntos
Eletroquímica , Hidrogênio , Platina , Concentração de Íons de Hidrogênio , Cinética , Platina/química , Energia Renovável , Água
6.
J Thorac Cardiovasc Surg ; 163(2): 539-548.e2, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-32654872

RESUMO

OBJECTIVE: Thoracic endovascular aortic repair is the standard of care for acute complicated type B aortic dissections, but long-term single-device outcomes are limited. METHODS: Fifty patients were treated with the Valiant Captivia thoracic stent graft (Medtronic Inc, Santa Rosa, Calif) for acute complicated type B aortic dissections in this prospective, nonrandomized Dissection Trial. All-cause mortality, secondary procedures, and serious adverse events were assessed, and a core lab evaluated images for aortic remodeling. RESULTS: Compliance for both clinical and imaging follow-up was 78% (18 out of 23) for the available patients at 5 years. Notable baseline characteristics were 86% of patients (43 out of 50) had malperfusion, 20% (10 out of 50) had ruptures, and 94% (46 out of 49) had DeBakey class IIIB dissections. The 5-year freedom from dissection-related mortality, secondary procedures related to the dissection, and endoleaks was 83%, 86%, and 85%, respectively. After 5 years, 89% of patients (16 out of 18) had a completely thrombosed false lumen in the stented segment of the aorta and the true lumen diameter over the length of stent graft was stable or increased for 94% of patients (16 out of 17) while the false lumen diameter was stable or decreased in 77% (13 out of 17) after 5 years. CONCLUSIONS: In the Dissection Trial, patients experienced positive and sustained measures of aortic remodeling. Survival outcomes, need for secondary procedures, and adverse event rates were consistent with previous thoracic endovascular aortic repair studies. Although limitations exist with the follow-up compliance, the Valiant Captivia thoracic stent graft system was effective in the long-term management of acute complicated type B aortic dissections in this patient population with a challenging condition.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Doença Aguda , Idoso , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/mortalidade , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/mortalidade , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/mortalidade , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/instrumentação , Procedimentos Endovasculares/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/cirurgia , Estudos Prospectivos , Reoperação , Stents , Fatores de Tempo , Resultado do Tratamento
7.
Eur Heart J Case Rep ; 5(9): ytab311, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34622132

RESUMO

BACKGROUND: Left ventricular (LV) pseudoaneurysm (PSA), also referred to as contained LV wall rupture, is a clinically uncommon but potentially life-threatening condition that can occur after myocardial infarction or cardiac surgery. If the anatomic characteristics of LV PSA are not eligible for the transfemoral approach, percutaneous closure of LV PSA can be technically difficult and appropriate approach selection may contribute to procedural success. CASE SUMMARY: An enlarging LV PSA was discovered in a 65-year-old man with Marfan syndrome and three prior cardiothoracic surgeries. Arterial access was not possible due to invagination of the previously placed surgical graft in the descending thoracic aorta. This was managed with a novel approach of simultaneous transseptal LV access and direct puncture of PSA through the chest wall followed by a vascular plug placement. DISCUSSION: This case demonstrates that percutaneous LV PSA closure using a hybrid approach of transseptal and direct apical puncture is a feasible and effective alternative for high-risk surgical candidates, although the anatomic characteristics are unsuitable for the transfemoral approach.

8.
Plant Physiol Biochem ; 166: 1001-1013, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34271533

RESUMO

Chromium (Cr) phytotoxicity affirmed the need of mitigation strategies to remediate polluted soils and restricts its accumulation in the food chains. Salicylic acid (SA) and silicon (Si) play pivotal roles in stimulating the plant performance and stress resilience. So far, their interactive effects against Cr-phytotoxicities are less known. Thus, we evaluated the beneficial roles of alone or/and combine applications of SA and Si in mitigating the toxic effects of Cr in the leaves and roots of rice (Oryza sativa) seedlings. Results indicated that SA (10 µM) and/or Si (5 µM) markedly retrieved the Cr (100 µM) induced toxicities by minimizing the Cr-accretion in both leaves and roots, enhancing the performance of light harvesting pigments (total chlorophylls and carotenoids), water retention and accumulation of osmolytes (water-soluble protein and total soluble sugars) and ultimately improved the growth and biomass. Additionally, SA and/or Si maintained the ionic balance by enhancing the nutrients transport, upregulated the ascorbate-glutathione (AsA-GSH) cycle enzymes, minimized the extra accumulation of reactive oxygen species (ROS) (H2O2 and O2•‒), malondialdehyde (MDA), recovered the membrane stability and damages in cellular ultrastructure in Cr-stressed rice plants. Overall findings suggested that SA underpins Si in mitigating the Cr-induced phytotoxicities on the above-reported parameters and combined applications of SA and Si were more effective than alone treatments. The uptake or cellular accumulation of Cr, osmoprotectants level and antioxidant defense system against oxidative stress can be considered as key toxicity biomarkers for the safe cultivation of rice in Cr-contaminated soils.


Assuntos
Antioxidantes , Oryza , Cromo/toxicidade , Homeostase , Peróxido de Hidrogênio , Estresse Oxidativo , Raízes de Plantas , Ácido Salicílico/farmacologia , Silício/farmacologia
9.
J Thorac Cardiovasc Surg ; 161(1): 44-45, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31757450
10.
Aorta (Stamford) ; 8(1): 14-17, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32599628

RESUMO

Type A aortic dissections during pregnancy are rare but lethal events, with reported mortalities as high as 60%. Unique changes in hemodynamics, hormone-related alterations in aortic tissue, and preexisting risk factors place patients at an elevated risk for dissection. We report a successful repair of a Type A aortic dissection at 32 weeks of gestation, with excellent outcomes in both mother and child. This report highlights the importance of gestational age and multidisciplinary effort.

11.
ACS Omega ; 5(17): 10123-10132, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32391500

RESUMO

A N-[(Benzyloxy)carbonyl]-l-alanyl-l-prolyl-l-leucine-N-cyclohexylcyclohexanamine (Cbz-APL) tripeptide-coated glassy carbon electrode (GCE)-based sensor was used for sensitive and selective recognition of cadmium ions in environmental water. Detailed cyclic voltammetric and electrochemical impedance spectroscopic studies were performed to investigate the charge transfer and sensing activity of the developed electrochemical sensor. Square wave anodic stripping voltammetry (SWASV) was employed to further investigate the sensitivity, selectivity, validity, and applicability of the developed sensor. A sharp electrochemical signal of oxidized Cd at -0.84 V versus Ag/AgCl provides evidence for the higher sensing ability of Cbz-APL/GCE than bare GCE at -0.79 V. Moreover, on Cbz-APL/GCE, extraordinary low detection limits of 4.34 fM and linearity range of 15 nM to 0.1 pM with coefficients of correlation higher than 0.99 for Cd2+ were achieved. Besides, the influence of inorganic and organic interferents on the targeted analyte signals was examined, and high selectivity of Cbz-APL/GCE for Cd2+ ions was observed. Lastly, the validity and applicability of the developed electrochemical sensor for the detection of Cd2+ ions were checked in real water samples, and 100% recovery was obtained.

12.
Ann Vasc Surg ; 68: 299-304, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32439524

RESUMO

BACKGROUND: The oldest segments of the population are expanding rapidly, and the number of thoracic endovascular aortic repairs (TEVARs) performed in the elderly parallels this trend. We describe our institutional TEVAR experience in octogenarians and nonagenarians. METHODS: All patients 80 years and older undergoing TEVAR at a single institution were reviewed using a prospectively maintained database. Baselines demographics, operative details, and outcomes were retrospectively analyzed. RESULTS: Twenty-five octogenarians and nonagenarians (age, 84.8 ± 3.7 years; 64% male) underwent TEVAR between January 2014 and January 2019. The most common preoperative comorbidities were hypertension (n = 24; 96%) and tobacco use (n = 18; 72%), and the mean modified frailty index was 0.32 ± 0.17. Degenerative aneurysms constituted the majority of aortic pathologies (60%), and most patients were symptomatic (64%), with a mean maximal aortic diameter of 62.7 ± 15.6 mm. Endoleaks were noted in 3 (12%) patients. Intensive care unit length of stay was 2.0 (1.5, 3.0) days, and the total length of stay was 5.0 (3.0, 7.0) days. In-hospital mortality was 12% (n = 3), while the overall 30-day mortality was 16% (n = 4). The median follow-up was 469.0 (76.0, 586.0) days. On univariate analysis, the presence of a postoperative complication was associated with a significantly increased risk of 30-day mortality (P < 0.01). CONCLUSIONS: Despite the inherently elevated operative risk among the elderly, this study demonstrates reasonable success rates for TEVAR in octogenarian and nonagenarian patients. In properly selected patients, advanced age alone should not be a prohibitive factor for TEVAR.


Assuntos
Doenças da Aorta/cirurgia , Implante de Prótese Vascular , Procedimentos Endovasculares , Fatores Etários , Idoso de 80 Anos ou mais , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/cirurgia , Doenças da Aorta/diagnóstico por imagem , Doenças da Aorta/mortalidade , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/mortalidade , Bases de Dados Factuais , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Tempo de Internação , Masculino , Complicações Pós-Operatórias/mortalidade , Complicações Pós-Operatórias/terapia , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
13.
Ann Vasc Surg ; 65: 54.e1-54.e4, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31981683

RESUMO

BACKGROUND: The risk of periprocedural stroke after thoracic endovascular aortic repair (TEVAR) ranges from 3% to 8%. Although cerebral embolic protection devices (CEPD) are widely utilized in transcatheter aortic valve replacement, there are currently no Food and Drug Administration approved CEPDs for use in TEVAR. We report our initial experience with the off-label use of a dual-filter CEPD in patients undergoing TEVAR. METHODS: Two patients at high risk for embolic stroke underwent TEVAR for descending thoracic aortic aneurysms (DTAAs) at a single institution. A dual-filter CEPD (Sentinel; Boston Scientific, Marlborough, MA) was used in an off-label fashion in both cases. Patient 1 was a 62-year-old woman with a 6.2-cm DTAA, extending from the left subclavian artery (LSCA) to the diaphragm (Zones 3-5) and associated with extensive atherosclerotic disease of the aortic arch. Patient 2 was a 78-year-old woman with a 6.3-cm DTAA, extending from the LSCA (Zone 2) to the sixth intercostal space (Zone 4) with associated mural thrombus. Given the proximity of the aneurysm to the LSCA, a left carotid-subclavian bypass was performed for planned LSCA coverage. RESULTS: Through a percutaneous right radial artery approach using a 6F sheath, the Sentinel dual-filter CEPD was delivered over a 0.014″ guidewire into the thoracic aorta. Under fluoroscopic guidance, the 2 filters were sequentially deployed in the innominate and left common carotid arteries, respectively. Appropriately sized devices were successfully delivered and deployed in the proximal and distal landing zones, respectively. Two devices were used for each patient. Completion angiograms showed successful exclusion of the DTAAs in both cases, without evidence of endoleak. The CEPD filters were retrieved in standard fashion without difficulty. Pathology demonstrated successful capture of embolic debris and fibrin clot in both patients. Neither patient exhibited neurological deficits or device-related complications. Both patients remained neurologically intact at 1- and 2-month follow-up, respectively. Surveillance angiograms revealed successful exclusion of the aneurysm without any evidence of endoleak. CONCLUSIONS: We report the novel off-label use of a dual-filter CEPD in 2 patients undergoing TEVAR. Pathological confirmation of embolic debris in the filters makes this a potential tool for stroke prevention during TEVAR in high-risk patients.


Assuntos
Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Aterosclerose/cirurgia , Implante de Prótese Vascular/instrumentação , Dispositivos de Proteção Embólica , Procedimentos Endovasculares/instrumentação , Embolia Intracraniana/prevenção & controle , Acidente Vascular Cerebral/prevenção & controle , Idoso , Aorta Torácica/diagnóstico por imagem , Aorta Torácica/fisiopatologia , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/fisiopatologia , Aterosclerose/diagnóstico por imagem , Aterosclerose/fisiopatologia , Prótese Vascular , Implante de Prótese Vascular/efeitos adversos , Procedimentos Endovasculares/efeitos adversos , Feminino , Humanos , Embolia Intracraniana/etiologia , Pessoa de Meia-Idade , Desenho de Prótese , Stents , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
14.
Phys Chem Chem Phys ; 22(4): 2046-2053, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31904072

RESUMO

The electrocatalytic CO2 reduction to yield C2 products is of particular interest in solar-to-fuel conversion schemes. The nanocrystalline oxide derived copper (ODCu) electrodes are specifically attractive due to their high faradaic efficiency towards C2 hydrocarbons like ethylene, ethane, acetate and ethanol. However, the mechanistic understanding of this special selectivity is still an impediment. In this work, ODCu is obtained from Cu2O nanowires and employed for electrocatalytic CO2 reduction, during which ethylene is found to be the major product with a faradaic efficiency of 65% at -0.8 V (vs. RHE). By in situ photoresponse measurement, combined with the ex situ structure and composition analysis, Cu2O is demonstrated to be persistent on the surface of ODCu throughout the CO2 reduction reaction (CO2RR) even at high applied bias (-1.0 V vs. RHE), while Cu2O is not present on the bulk Cu foil. Density functional theory calculations are employed to further investigate the correlation between the surface Cu2O on ODCu and its C2 selectivity performance, which is attributed to the orbital interactions between the persistent oxide and CO2 reduction intermediates. It should be noted that uncovering the active sites is the initial step to understand the surface reaction chemistry in CO2RR; here, we propose that the presence of Cu2O is the key for C2 selectivity during CO2RR in the ODCu system, which may facilitate the development of highly efficient catalysts.

15.
ACS Omega ; 4(16): 16860-16866, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31646232

RESUMO

The glassy carbon electrode was fabricated with multifunctional bis-triazole-appended calix[4]arene and then used for the simultaneous detection of Zn(II), Pb(II), As(III), and Hg(II). Before applying the square-wave anodic stripping voltammetry, the sensitivity and precision of the modified electrode was assured by optimizing various conditions such as the modifier concentration, pH of the solution, deposition potential, accumulation time, and supporting electrolytes. The modified glassy carbon electrode was found to be responsive up to picomolar limits for the aforementioned heavy metal ions, which is a concentration limit much lower than the threshold level permitted by the World Health Organization. Importantly, the designed sensing platform showed anti-interference ability, good stability, repeatability, reproducibility, and applicability for the detection of multiple metal ions. The detection limits obtained for Zn(II), Pb(II), As(III), and Hg(II) are 66.3, 14.6, 71.9, and 28.9 pM, respectively.

16.
ACS Omega ; 4(12): 15004-15011, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31552342

RESUMO

The hitherto unknown influence of 1,10-phenonthroline (1,10-phen) and its derivatives on the weak chemiluminescence (CL) of periodate-peroxide has been investigated, and a novel method for CL catalysis is described. Herein, we have deconvoluted the variation in CL intensity arising from the addition of various derivatives of 1,10-phen. Interestingly, similar derivatives of 1,10-phen show interesting differences in their reactivity toward CL. Electron-withdrawing substituents on 1,10-phen boosted the CL signals, indicating a negative charge buildup on 1,10-phen in the rate-determining step. The 1,10-phen derivatives having substitution at the C5=C6 position resulted in no CL signals due to the blockage of the reactive site. Mechanistic investigations are interpreted in terms of free radical (H2O2 reaction), followed by the oxygen atom transfer via an electrophilic attack of IO4 - (IO4 - reaction) on 1,10-phen resulting in dioxetane with enhanced CL emission. Additionally, the relationship between electronic structures and photophysical properties was investigated using density functional theory. Our results are expected to open up promising application of 1,10-phen as a molecular catalyst, providing a new strategy for metal-free catalytic CL enhancement reaction. We believe that this would foster in gleaning more detailed information on the nature of these reactions, thereby leading to a deeper understanding of the CL mechanism.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 176: 155-167, 2017 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-28092826

RESUMO

A novel Schiff base, 1-((2, 4-dimethylphenylimino)methyl)naphthalen-2-ol abbreviated as (HL) and its four metallic complexes were synthesized and confirmed by 1H and 13C NMR, FTIR, TGA and UV-Visible spectroscopy. Schiff base was also characterized by X-ray analysis. The photometric and electrochemical responses of all the synthesized compounds were investigated in a wide pH range. Structures of the compounds were optimized computationally for the evaluation of different physico-chemical parameters. On the basis of electrochemical results the redox mechanistic pathways of the compounds were proposed. The cytotoxicity analysis on Hela cells revealed that HL and its complexes inhibit cell growth as revealed from their IC50 values (HL):106.7µM, (L2VO): 40.66µM, (L2Sn): 5.92µM, (L2Zn): 42.82 and (L2Co): 107.68µM. The compounds were tested for anti-diabetic, triglyceride, cholesterol, anti-microbial, anti-fungal and enzyme inhibition activities. The results revealed that HL and its complexes are promising new therapeutic options as these compounds exhibit strong activity against cancer cells, diabetics, fungal and microbial inhibition.


Assuntos
Eletroquímica/métodos , Metais/química , Bases de Schiff/síntese química , Bases de Schiff/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Glicemia/metabolismo , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Difusão , Elétrons , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Hipoglicemiantes/farmacologia , Concentração Inibidora 50 , Limite de Detecção , Masculino , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , Oxirredução , Espectrofotometria Ultravioleta , Termogravimetria
18.
J Thorac Cardiovasc Surg ; 153(3): 521-527, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27932024

RESUMO

OBJECTIVE: Postoperative myocardial infarction remains a serious complication in cardiac surgery. The incidence and impact of this condition in acute type A aortic dissection are poorly understood. METHODS: A total of 1445 patients with acute type A aortic dissection who underwent surgery were enrolled in the International Registry of Acute Aortic Dissection from 1996 to 2013. Individuals with preoperative myocardial infarction at hospital presentation and a history of myocardial infarction were excluded. Patients with postoperative myocardial infarction (n = 38, 2.6%) were compared with those without postoperative myocardial infarction (n = 1407, 97.4%). RESULTS: The postoperative myocardial infarction group was more often of white race (100% vs 90%, P = .043) with bicuspid aortic valve (15.6% vs 4.5%, P = .015). Imaging demonstrated more aortic root involvement (75.8% vs 49.5%, P = .003), pericardial effusion (65.5% vs 44.1%, P = .022), and coronary artery compromise (27.3% vs 10.2%, P = .022). Patients with postoperative myocardial infarction were more frequently hypotensive or in shock during surgery (42.9% vs 25.5%, P = .021). Patients with postoperative myocardial infarction were more likely to have undergone root replacement (54.5% vs 33.3%, P = .011), coronary artery bypass grafting (28.6% vs 7.4%, P < .001), or aortic valve replacement (40.0% vs 23.8%, P = .027), and less likely to have had complete arch replacement (2.8% vs 14.0%, P = .050). Median circulatory arrest time was higher in postoperative myocardial infarction (60 vs 38 minutes, P = .024). In-hospital mortality (57.9% vs 16.3%, P < .001) and Kaplan-Meier estimates of 5-year mortality (P = .007) were distinctly higher in postoperative myocardial infarction. CONCLUSIONS: Postoperative myocardial infarction is a devastating complication of type A aortic dissection repair. It is associated with bicuspid aortic valve, root involvement, pericardial effusion, and extent of surgical repair. Patients with postoperative myocardial infarction have higher serious postoperative complications, in-hospital mortality, and 5-year mortality rates than those without postoperative myocardial infarction.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Implante de Prótese Vascular/efeitos adversos , Infarto do Miocárdio/etiologia , Complicações Pós-Operatórias/etiologia , Sistema de Registros , Doença Aguda , Dissecção Aórtica/diagnóstico , Aneurisma da Aorta Torácica/diagnóstico , Angiografia por Tomografia Computadorizada , Angiografia Coronária , Eletrocardiografia , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Mortalidade Hospitalar/tendências , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia
19.
Ann Cardiothorac Surg ; 5(4): 389-96, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27563553

RESUMO

Acute type A aortic dissection is a potentially lethal condition which requires immediate diagnostic and therapeutic intervention. Open surgical repair remains the standard of care as survival rates continue to improve in the modern surgical era. Unfortunately, up to twenty percent of patients are denied surgical therapy because they are deemed medically unfit to undergo open repair. The application of thoracic endovascular aortic repair (TEVAR) has changed the treatment paradigm for aortic disease involving the descending thoracic aorta and may be a viable rescue option for patients with type A dissection who are not eligible for open surgical repair. New endovascular devices and advanced image-guided procedures are continually evolving. This article summarizes the pathology of aortic dissection and focuses on currently available endovascular solutions for transapical and transfemoral stent graft deployment for acute aortic dissection involving the ascending aorta for selected patients who are ineligible for open surgical repair.

20.
Environ Monit Assess ; 188(5): 267, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27048492

RESUMO

Gaseous pollutant emissions from brick kiln industries deteriorate the current state of ambient air quality in Pakistan and worldwide. These gaseous pollutants affect the health of plants and may decrease plant growth and yield. A field experiment that was conducted to monitor the concentration of gaseous pollutants emitted mainly from brick kilns in the ambient air and associated impacts on the growth and physiological attributes of the two wheat (Triticum spp.) cultivars. Plants were grown at three sites, including control (Ayub Agriculture Research Institute, AARI), low pollution (LP) site (Small Estate Industry), and high pollution (HP) site (Sidar Bypass), of Faisalabad, Pakistan. Monitoring of ambient air pollution at experimental sites was carried out using the state-of-art ambient air analyzers. Plants were harvested after 120 days of germination and were analyzed for different growth attributes. Results showed that the hourly average concentration of gaseous air pollutants CO, NO2, SO2, and PM10 at HP site were significantly higher than the LP and control sites. Similarly, gaseous pollutants decreased plant height, straw and grain yield, photosynthesis and increased physical injury, and metal concentrations in the grains. However, wheat response toward gaseous pollutants did not differ between cultivars (Galaxy and 8173) studied. Overall, the results indicated that brick kiln emissions could reduce the performance of wheat grown in the soils around kilns and confirm the adverse impacts of pollutants on the growth, yield, and quality of the wheat.


Assuntos
Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Materiais de Construção , Monitoramento Ambiental , Fotossíntese/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos dos fármacos , Triticum/efeitos dos fármacos , Agricultura , Poluição do Ar/análise , Gases , Indústrias , Metais , Paquistão , Triticum/crescimento & desenvolvimento
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