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1.
Int J Mol Sci ; 25(2)2024 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-38256094

RESUMO

The fixation of carbon dioxide with epoxides is one of the most attractive methods for the green utilisation of this greenhouse gas and leads to many valuable chemicals. This process is characterised by 100% atom efficiency; however, an efficient catalyst is required to achieve satisfactory yields. Metal-organic frameworks (MOFs) are recognised as being extremely promising for this purpose. Nevertheless, many of the proposed catalysts are based on ions of rare elements or elements not entirely safe for the environment; this is notable with commercially unavailable ligands. In an effort to develop novel catalysts for CO2 fixation on an industrial scale, we propose novel MOFs, which consist of aluminium ions coordinated with commercially available 1,4-naphthalene dicarboxylic acid (Al@NDC) and their nanocomposites with gold nanoparticles entrapped inside their structure (AlAu@NDC). Due to the application of 4-amino triazole and 5-amino tetrazole as crystallization mediators, the morphology of the synthesised materials can be modified. The introduction of gold nanoparticles (AuNPs) into the structure of the synthesised Al-based MOFs causes the change in morphology from nano cuboids to nanoflakes, simultaneously decreasing their porosity. However, the homogeneity of the nanostructures in the system is preserved. All synthesised MOF materials are highly crystalline, and the simulation of PXRD patterns suggests the same tetragonal crystallographic system for all fabricated nanomaterials. The fabricated materials are proven to be highly efficient catalysts for carbon dioxide cycloaddition with a series of model epoxides: epichlorohydrin; glycidol; styrene oxide; and propylene oxide. Applying the synthesised catalysts enables the reactions to be performed under mild conditions (90 °C; 1 MPa CO2) within a short time and with high conversion and yield (90% conversion of glycidol towards glycerol carbonate with 89% product yield within 2 h). The developed nanocatalysts can be easily separated from the reaction mixture and reused several times (both conversion and yield do not change after five cycles). The excellent performance of the fabricated catalytic materials might be explained by their high microporosity (from 421 m2 g-1 to 735 m2 g-1); many catalytic centres in the structure exhibit Lewis acids' behaviour, increased capacity for CO2 adsorption, and high stability. The presence of AuNPs in the synthesised nanocatalysts (0.8% w/w) enables the reaction to be performed with a higher yield within a shorter time; this is especially important for less-active epoxides such as propylene oxide (two times higher yield was obtained using a nanocomposite, in comparison with Al-MOF without nanoparticles).


Assuntos
Nanopartículas Metálicas , Estruturas Metalorgânicas , Propanóis , Dióxido de Carbono , Ouro , Alumínio , Compostos de Epóxi , Íons
2.
Org Lett ; 25(37): 6818-6822, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37655810

RESUMO

Application of high-pressure conditions enables enantioselective Michael-type addition of dialkyl malonates to ß-arylethenesulfonyl fluorides. The reaction is efficiently catalyzed with 5 mol % of tertiary amino-thiourea at 9 kbar. Chiral alkanesulfonyl fluorides are formed in yields of up to 96% and enantioselectivities of up to 92%. Functionalization of the adducts via sulfur fluoride exchange (SuFEx) reaction and desulfonylative cyclization is demonstrated.

3.
Sensors (Basel) ; 23(7)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37050657

RESUMO

The passive multipliers based on semiconductor diodes, most frequently a Schottky type, should be driven by a certain value of input power, where the conversion losses are optimal. This means that the variation in the input power level causes the change in the output power level. A solution to this issue is the integration of an output power amplifier, which in the state of saturation provides quasi-stabilization of the output power. Practically, this approach gives an unsatisfactory performance: weak stabilization or narrow input power range. This paper comprises a concept of an active frequency multiplier with the use of one FET transistor and a special adaptive bias circuit in order to obtain a very wide input power range when the output power is stable. The principle of the operation, design guidelines, and measurement results have been presented for an example circuit of the frequency doubler. The results show the possibility to obtain up to 10 dB input power range for a 1 dB change in output power level without the use of additional amplifiers.

4.
Cent Eur J Immunol ; 47(1): 58-62, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600156

RESUMO

In December 2019, the World Health Organization (WHO) reported that China had accumulated pneumonia of unclear etiology in Wuhan. According to WHO recommendations, in strictly defined situations, antigen tests can be implemented into the diagnostic algorithm to reduce the number of molecular tests performed and support the rapid identification and treatment of COVID-19 patients. According to WHO recommendations, the antigen test for diagnostic use should have a sensitivity of ≥ 80% and a specificity of ≥ 97% compared to molecular tests (NAAT). Based on the comparative analysis, the sensitivity and specificity of the SARS-CoV-2 Antigen ELISA test were determined concerning the RT-PCR reference method. The sensitivity of the SARS-CoV-2 Antigen ELISA was 100% (51/51) and the specificity was 98.84%. The obtained data demonstrate that the analyzed antigen test meets both the WHO and the Ministry of Health criteria.

5.
J Clin Med ; 11(7)2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35407387

RESUMO

Background: Whereas the efficacy and safety of intravascular lithotripsy (IVL) have been confirmed in de novo calcified coronary lesions, little is known about its utility in treating stent underexpansion. This study aimed to investigate the impact of IVL in treating stent underexpansion. Methods and Results: Consecutive patients with stent underexpansion treated with IVL entered the multicenter IVL-Dragon Registry. The procedural success (primary efficacy endpoint) was defined as a relative stent expansion >80%. Thirty days device-oriented composite endpoint (DOCE) (defined as a composite of cardiac death, target lesion revascularization, or target vessel myocardial infarction) was the secondary endpoint. A total of 62 patients were enrolled. The primary efficacy endpoint was achieved in 72.6% of patients. Both stent underexpansion 58.5% (47.5−69.7) vs. 11.4% (5.8−20.7), p < 0.001, and the stenotic area 82.6% (72.4−90.8) vs. 21.5% (11.1−37.2), p < 0.001, measured by quantitative coronary angiography improved significantly after IVL. Intravascular imaging confirmed increased stent expansion following IVL from 37.5% (16.0−66.0) to 86.0% (69.2−90.7), p < 0.001, by optical coherence tomography and from 57.0% (31.5−77.2) to 89.0% (85.0−92.0), p = 0.002, by intravascular ultrasound. Secondary endpoint occurred in one (1.6%) patient caused by cardiac death. There was no target lesion revascularization or target vessel myocardial infarction during the 30-day follow-up. Conclusions: In this real-life, largest-to-date analysis of IVL use to manage underexpanded stent, IVL proved to be an effective and safe method for facilitating stent expansion and increasing luminal gain.

6.
Artigo em Inglês | MEDLINE | ID: mdl-35162210

RESUMO

This path analysis of mothers of children with autism aimed to investigate the relationship between maternal burnout and the mother's subjective reporting of difficulty in childcare, family function, and personality traits. A total of 410 mothers of children with autism (mean age 39.03, SD 7.42) completed four questionnaires: Parental Burnout Measure (PBM-12), International Personality Item Pool-Big Five Markers (IPIP-BFM-20), Flexibility and Cohesion Evaluation Scales (FACES-IV), and a survey on childcare difficulties. Path analysis using two predetermined models was used to examine the interrelations. Both models fit the empirical data equally with a Root Mean Square Error of Approximation (RMSEA) index of 0.000 and a 90% confidence interval (model 1: 0.000-0.052; model 2: 0.000-0.059). Path analysis revealed similar fit indexes for both models: (a) burnout is a mediator between exogenous variables and family functioning, and (b) family functioning is an indirect mediator between exogenous variables and burnout. These findings suggest that increased maternal emotional instability (neuroticism) and conscientiousness can lead to increased family communication problems, which may further lead to a breakdown of the equilibrium in the family system, resulting in the mother's dissatisfaction with family life and a consequent increased risk of maternal burnout.


Assuntos
Transtorno Autístico , Esgotamento Profissional , Adulto , Transtorno Autístico/epidemiologia , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/psicologia , Esgotamento Psicológico , Criança , Feminino , Humanos , Mães/psicologia , Personalidade , Inquéritos e Questionários
7.
New Dir Child Adolesc Dev ; 2020(174): 137-158, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33201567

RESUMO

This study examined the factorial structure of the Polish version of the Parental Burnout Assessment (PBA-PL) and its relation with other variables, previously shown to be antecedents or outcomes of parental burnout. The PBA-PL was administered to a total sample of 2,130 parents along with other instruments depending on the study. Factorial analyses of the PBA-PL supported both the original four-factor model of parental burnout (exhaustion related to parenting, feelings of being fed up with parenting, emotional distancing from one's children, and contrast with previous parental self) and a second-order model with a global parental burnout underlying the four first-order factors. Both subscale and global scores were reliable. Significant correlations were found between PBA-PL and neuroticism, emotional intelligence, maladaptive perfectionism, perceived social support, depressive symptoms, marital satisfaction, and life satisfaction. PBA-PL also predicted both parental neglect and parental violence beyond socio-demographic factors, depression, and job burnout.


Assuntos
Esgotamento Profissional , Esgotamento Psicológico , Esgotamento Profissional/diagnóstico , Esgotamento Psicológico/diagnóstico , Criança , Humanos , Poder Familiar , Pais , Polônia
8.
Cytokine ; 113: 185-194, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30539780

RESUMO

INTRODUCTION: A growing body of evidence indicates that brain cytokines are involved in the control of the cardiovascular system. Tumour necrosis factor (TNF) is an archetypal cytokine, which exerts its proinflammatory actions via type 1 receptor (TNFR1). Interleukin 10 (IL-10) plays a critical anti-inflammatory role by binding to its receptor (IL-10Ra). The orchestrated inflammatory response is largely dependent on an intricate balance between proinflammatory and anti-inflammatory cytokines and expression of their receptors. AIM: In the study we evaluated the expression of the cytokines and their receptors in the brains of spontaneously hypertensive (SH) and normotensive Wistar-Kyoto (WKY) rats, and how the cytokines affect arterial blood pressure. METHODS: In SH and WKY rats we recorded systolic blood pressure with tail cuff method and measured concentration of TNF, IL-10, TNFR1, and IL-10Ra in the serum, the brainstem, and the hypothalamus; we also measured serum concentrations of copeptin, a surrogate of vasopressin release, angiotensin II and norepinephrine. We immunostained brainstem sections for TNFR1, IL-10Ra, neurons, astrocytes and microglia for confocal imaging. In urethane anaesthetized SH and WKY rats, we invasively recorded blood pressure response to intracerebroventricular (IVC) infusion of TNF or IL-10. We also pharmacologically evaluated baroreflex with phenylephrine and chemoreflex with cyanide in SH and WKY rats. RESULTS: Compared to WKY rats, SH rats had: (1) higher blood pressure; (2) blunted baroreflex and augmented peripheral chemoreflex; (3) greater pressor response to ICV infused TNF and greater hypotensive response to ICV infused IL-10; (4) higher concentration of TNF in the ventral and dorsal aspects of the medulla oblongata; (5) higher expression of TNFR1 in the dorsal medulla; (6) higher concentration of IL-10 in both aspects of the medulla; (7) lower expression of IL-10Ra in the dorsal medulla. Confocal imaging showed co-localization of TNFR1 and IL-10Ra with neurons, astrocytes and microglia in both SH and WKY rats. The concentration of the cytokines and their receptors were significantly higher in the brain than in the serum. There were no significant differences in the concentration of the cytokines and their receptors in the hypothalamic region and in the serum between SH and WKY rats. Serum concentrations of norepinephrine, angiotensin II and copeptin were similar between SH and WKY rats. CONCLUSIONS: Taken together, these findings suggest the presence of a potent milieu for effective TNF signalling in the brainstem, which is associated with the hypertensive phenotype and enhanced hemodynamic response to intrabrain administration of the cytokines. In addition, we hypothesize that the increased IL-10 concentration in the brainstem is a compensatory mechanism for the upregulated TNF system.


Assuntos
Pressão Sanguínea , Tronco Encefálico/metabolismo , Hipotálamo/metabolismo , Interleucina-10/sangue , Receptores de Interleucina-10/sangue , Receptores Tipo I de Fatores de Necrose Tumoral/sangue , Fator de Necrose Tumoral alfa/sangue , Animais , Astrócitos/citologia , Astrócitos/metabolismo , Tronco Encefálico/citologia , Hipotálamo/citologia , Microglia/citologia , Microglia/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Transdução de Sinais
9.
Org Biomol Chem ; 16(23): 4365-4371, 2018 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-29850721

RESUMO

The application of high pressure (up to 9 kbar) allows for relatively fast (1-5 h) and highly enantioselective 1,4-addition of nitromethane and 2-nitropropane to chalcones at room temperature with substantial reduction of catalyst loading (0.2-1 mol% of cinchona alkaloid-based thioureas and squaramides). Various γ-nitroketones were obtained at 9 kbar with high yield and enantioselectivity (up to 98%), whereas in control experiments at atmospheric pressure usually only a small amount (<10%) of products were formed after 20 h.

10.
J Interv Cardiol ; 31(5): 599-607, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29869380

RESUMO

OBJECTIVES: We evaluated the impact of stent inflation pressure and type of guidewire on "jailed" coronary guidewire damage occurring during bifurcation angioplasty. BACKGROUND: Despite new techniques and treatment options during percutaneous coronary intervention (PCI) we still observe peri- and postoperative complications for to various known and unknown reasons. METHODS: Patients undergoing PCI within the coronary bifurcation were randomly assigned to one of four groups: Pilot 50 or BMW guidewire and pressure ≤12 or >12 atm. After PCI each "jailed" guidewire was evaluated under an optical microscope. The Wide Beast Scale (WBS) was developed for the internal purposes of the study and was used for qualitative assessment. Also, the inflation pressure, the patients' characteristics and the technical parameters of the procedure were recorded. RESULTS: The clinical characteristics were similar in all the groups. There was no statistical significance of the degree of damage, rated on the WBS, for either guidewire group with respect to inflation pressure (P = 0.49). The prevalence of guidewire damage was higher in the BMW versus the Pilot 50 group (98.4% vs 67.4% respectively, P = 0.00001) as was the severity of the damage (grades 3 and 4) in BMW versus Pilot 50 (55.6% vs 13.0% respectively, P = 0.00001). CONCLUSIONS: The inflation pressure during stent implantation had no impact on "jailed" guidewire damage. The difference in the prevalence of serious damage and total damage number was statistically significant for the BMW guidewire compared to the Pilot50. The BMW guidewire was an independent predictor of the degree of damage to the guidewire.


Assuntos
Implante de Prótese Vascular , Angiografia Coronária , Vasos Coronários/lesões , Complicações Intraoperatórias , Stents/efeitos adversos , Lesões do Sistema Vascular , Idoso , Implante de Prótese Vascular/efeitos adversos , Implante de Prótese Vascular/métodos , Angiografia Coronária/efeitos adversos , Angiografia Coronária/instrumentação , Angiografia Coronária/métodos , Análise de Falha de Equipamento , Feminino , Humanos , Incidência , Complicações Intraoperatórias/epidemiologia , Complicações Intraoperatórias/etiologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Lesões do Sistema Vascular/epidemiologia , Lesões do Sistema Vascular/etiologia
11.
Talanta ; 183: 102-107, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29567150

RESUMO

The identification of groups of ligands binding metals is a crucial issue for the better understanding of their bioaccessibility. In the current study, we have intended an approach for identification of Zn-binding ligands based on using capillary electrophoresis combined with inductively coupled plasma mass spectrometry (CE-ICP-MS) and tandem electrospray ionization mass spectrometry (CE-ESI-MS/MS). The approach, which featured the use of the coupling of capillary electrophoresis with inductively coupled plasma mass spectrometry allows to separate and observe zinc ions present in complexes with respect to their size and charge and to identify nine compounds with zinc isotopic profile. CE-ICP-MS provides us with information about presence of zinc species and elemental information about zinc distribution. CE-ESI-MS/MS provide us with information about the most favorable Zn binding ligands: amino acids, flavonols, stilbenoids, fenolic acids and carotenoids. The presented work is the continuation of previous studies based on using LC-ESI-MS/MS, though, now we presented a new solutions with the possibility of changing detectors without changing the separation techniques, what is important without re-optimizing the method. The new presented method allows to identify the zinc-binding ligands in shorter time.


Assuntos
Aminoácidos/análise , Carotenoides/análise , Flavonóis/análise , Lycium/química , Extratos Vegetais/química , Estilbenos/análise , Zinco/química , Eletroforese Capilar , Frutas/química , Ligantes , Espectrometria de Massas
12.
Artigo em Inglês | MEDLINE | ID: mdl-28425201

RESUMO

The paper presents an applied methodology for numerical finite element analysis of coronary stent crimping and the free inflation process with the use of a folded noncompliant angioplasty balloon. The use of an implicit scheme is considered as the most original part of the work, as an explicit finite element procedure is very often preferred. Hitherto, when the implicit solution was used for the finite element solution, the simulated issue was largely simplified. Therefore, the authors focused on the modelling methodology with minimum possible simplification, ie, a full load path (compression and inflation in single analysis), solid element discretization, and sophisticated contact models (bodies with highly different stiffness). The obtained results are partially compared with experimental data (radial force during the crimping procedure) and present satisfactory compliance. The authors believe that presented methodology allow for significant improvement of the obtained results, as well as potential extension of the research scope, compared to previous efforts performed using the explicit integration scheme. Moreover, the presented methodology is believed to be suitable for sensitivity and optimization studies.


Assuntos
Análise de Elementos Finitos , Stents , Angioplastia com Balão , Humanos , Desenho de Prótese
13.
J Chromatogr A ; 1492: 70-78, 2017 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-28268000

RESUMO

Goji berries (Lycium Barbarum, L.) are known for their nutritional potential as a great source of trace metals (e.g., copper, zinc and manganese) which are present in the form of highly bioaccessible compounds. In order to assess the bioaccessibility of trace elements and to identify compounds responsible for better bioaccessibility of copper and zinc, an in vitro simulation of gastrointestinal digestion was used in this study. The total content of trace metals was evaluated using sample digestion followed by inductively coupled plasma mass spectrometry. Bioaccessibility of trace elements was estimated by size exclusion chromatography coupled to inductively coupled plasma mass spectrometry. These analytical methods were used to analyse samples of goji berries to determine the highest amount of elements. For total trace metal content in goji berries, Zn had the highest level of the three studied (10.6µgg-1), while the total content of manganese and copper was 9.9µgg-1 and 6.1µgg-1, respectively. Additionally, the analysed metals were found to be highly bioaccessible to the human body (about 56% for Mn, 72% for Cu and 64% for Zn in the gastric extract and approximately 35% for Mn, 23% for Cu and 31% for Zn in the case of gastrointestinal extract). To obtain information about metal complexes present in goji berries, extraction treatment using different solutions (ionic liquid, HEPES, SDS, Tris-HCl, ammonium acetate, water) was performed. Enzymatic treatment using pectinase and hemicellulase was also checked. Extracts of berries were analysed by SEC-ICP-MS and µHPLC-ESI-MS/MS techniques. The ionic liquid and pectinase extraction helped efficiently extract copper (seven compounds) and zinc (four compounds) complexes. Compounds identified in goji berries are most likely to be responsible for better bioaccessibility of those elements to the human organism.


Assuntos
Lycium/química , Espectrometria de Massas , Oligoelementos/análise , Cromatografia em Gel , Cromatografia Líquida de Alta Pressão , Cobre/análise , Humanos , Lycium/metabolismo , Manganês/análise , Extratos Vegetais/química , Espectrometria de Massas em Tandem , Zinco/análise
14.
Neuropeptides ; 58: 67-72, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27241175

RESUMO

INTRODUCTION: Emerging evidence indicates that increased levels of TNF in the brain are associated with hypertension. Nitric oxide synthase (NOS) is involved in the central control of the cardiovascular system, exerting both pro- and antihypertensive effects. TNF induces hypothalamic synthesis of nitric oxide. AIM: We checked if acutely administered TNF into the cerebral ventricles affects arterial blood pressure, heart rate and baroreflex sensitivity, and whether TNF actions are dependent on NOS in normotensive rats. METHODS: We carried out hemodynamic measurements in 6 groups of freely moving, adult Sprague-Dawley male rats, intracerebroventricularly (ICV) infused with either: 1) saline (5µl/h); 2) TNF (200ng/5µl/h); 3) non-selective NO synthase inhibitor - l-NG-Nitroarginine Methyl Ester (l-NAME) (1mg/5µl/h); 4) TNF together with l-NAME (200ng and 1mg/5µl/h, respectively); 5) neuronal NO synthase inhibitor - 7-nitroindazole sodium salt (7-NI) (20µg/10µl/h); 6) or TNF together with 7-NI (200ng and 20µg/10µl/h, respectively). Mean arterial blood pressure (MABP), heart rate (HR) and spontaneous baroreflex sensitivity (sBRS) evaluated by the sequence method were analysed. RESULTS: ICV infusion of TNF caused a significant increase in MABP accompanied by a transient increase in HR, and a decrease in sBRS. ICV infusion of l-NAME increased MABP, but it did not change HR, nor sBRS. ICV infusion of 7-NI did not affect MABP, nor HR, nor sBRS. TNF administered together with l-NAME increased MABP with a transient increase in HR without changes of sBRS. Similarly, ICV infusion of TNF with 7-NI increased MABP without changes in HR and sBRS. CONCLUSIONS: Centrally administered TNF increases MABP and HR and blunts sBRS. The pressor effect of TNF appears to be independent of NOS activity in the brain. Inhibition of nNOS restores sBRS in TNF treated rats.


Assuntos
Pressão Arterial/efeitos dos fármacos , Hipertensão/fisiopatologia , Óxido Nítrico Sintase/fisiologia , Fator de Necrose Tumoral alfa/administração & dosagem , Fator de Necrose Tumoral alfa/fisiologia , Administração Intravenosa , Animais , Barorreflexo/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Masculino , NG-Nitroarginina Metil Éster/administração & dosagem , Óxido Nítrico Sintase/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley
15.
Electrophoresis ; 37(3): 536-44, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26311334

RESUMO

PDMS is a very popular material used for fabrication of Lab-on-a-Chip systems for biological applications. Although PDMS has numerous advantages, it is a highly hydrophobic material, which inhibits adhesion and proliferation of the cells. PDMS surface modifications are used to enrich growth of the cells. However, due to the fact that each cell type has specific adhesion, it is necessary to optimize the parameters of these modifications. In this paper, we present an investigation of normal (MRC-5) and carcinoma (A549) human lung cell adhesion and proliferation on modified PDMS surfaces. We have chosen these cell types because often they are used as models for basic cancer research. To the best of our knowledge, this is the first presentation of this type of investigation. The combination of a gas-phase processing (oxygen plasma or ultraviolet irradiation) and wet chemical methods based on proteins' adsorption was used in our experiments. Different proteins such as poly-l-lysine, fibronectin, laminin, gelatin, and collagen were incubated with the activated PDMS samples. To compare with other works, here, we also examined how ratio of prepolymer to curing agent (5:1, 10:1, and 20:1) influences PDMS hydrophilicity during further modifications. The highest adhesion of the tested cells was observed for the usage of collagen, regardless of PDMS ratio. However, the MRC-5 cell line demonstrated better adhesion than A549 cells. This is probably due to the difference in their morphology and type (normal/cancer).


Assuntos
Adesão Celular/efeitos dos fármacos , Técnicas de Cultura de Células/instrumentação , Dimetilpolisiloxanos/química , Dimetilpolisiloxanos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Colágeno/farmacologia , Humanos , Dispositivos Lab-On-A-Chip , Polilisina/farmacologia , Propriedades de Superfície
16.
Org Lett ; 16(22): 5930-3, 2014 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-25390507

RESUMO

A very effective high-pressure-induced acceleration of asymmetric organocatalytic conjugate addition of nitromethane to sterically congested ß,ß-disubstituted ß-CF3 enones has been developed. A combination of pressure (8-10 kbar) and noncovalent catalysis with low-loading of chiral tertiary amine-thioureas (0.5-3 mol %) is shown to provide very efficient access to a wide range of γ-nitroketones containing trifluoromethylated all-carbon quaternary stereogenic centers in the ß-position (80-97%, 92-98% ee).

17.
Acta Bioeng Biomech ; 16(4): 23-31, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25597960

RESUMO

PURPOSE: The paper presents the process of numerical modeling and simulation of balloon angioplasty of the coronary artery using Finite Element Method. METHODS: The authors focused on the issue of applying adequate pressure in an arterial tissue during the post-dilatation process in the "kissing balloon" stenting technique applied to patients with bifurcation stenosis. Despite great progress in the field of interventional cardiology, angioplasty in bifurcations still belongs to the most difficult interventions, generally being less effective and more risky than in the cases of straight stenosis. RESULTS: During the modeling procedures and further simulations, the authors focused on mutual cooperation of non-compliant angioplasty balloons and the coronary artery. The other goal was to develop a sufficiently accurate model of the coronary artery fragment, including its bifurcation and angioplasty balloons; however, it was decided to ignore the modeling of coronary stents. CONCLUSIONS: The issue undertaken is considered as relatively complicated and complex but, in the authors' opinion, the implementation of advanced computer aided engineering techniques may, in this case, answer several important questions without the need of performing costly and aggravating in vivo tests.


Assuntos
Vasos Coronários/patologia , Vasos Coronários/cirurgia , Análise de Elementos Finitos , Intervenção Coronária Percutânea , Angioplastia com Balão , Simulação por Computador , Vasos Coronários/diagnóstico por imagem , Elasticidade , Humanos , Modelos Cardiovasculares , Análise Numérica Assistida por Computador , Pressão , Estresse Mecânico , Fatores de Tempo , Tomografia Computadorizada por Raios X
18.
Org Lett ; 14(16): 4222-5, 2012 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-22873407

RESUMO

A practical and highly enantioselective Michael addition of malonates to enones catalyzed by simple and readily available bifunctional primary amine-thiourea derived from 1,2-diaminocyclohexane is reported. The addition of weak acids and elevated temperature (ca. 50 °C) improved the efficiency of the Michael reaction. This approach enables the efficient synthesis of 1,5-ketoesters with good yields, excellent enantioselectivities (up to 99% ee), and low loading (0.5-5 mol %) of simple chiral primary amine-thiourea catalysts, and is applicable in multigram scale synthesis.

19.
Am J Cardiol ; 110(8): 1106-12, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22748353

RESUMO

Frequency-domain optical coherence tomography (FD-OCT) is becoming a useful diagnostic tool for coronary imaging for quantitative coronary analysis. Second-generation FD-OCT produces detailed coronary lumen images. However, the reproducibility of coronary measurements using FD-OCT in humans has not been thoroughly explored. Our goal was to determine the intraobserver, interobserver, and interpullback reproducibility of the in vivo FD-OCT measurements of the lumen area and/or lesion length. Twenty-five patients undergoing coronary angioplasty were included. In all subjects, FD-OCT pullbacks (20 mm/s) were acquired twice from the same coronary segment different from the target lesion, at an interval of 5 minutes, with no other intervention. A total of 9,396 cross-sectional lumen area frames and the relative coronary lesion length of each pullback were analyzed off-line with dedicated software by 2 independent expert readers (A and B). We compared the lumen area and length measurements as follows: pullback 1, read by reader A twice at an interval of 7 days (intraobserver analysis); pullback 1, independently read by readers A and B (interobserver comparison); and pullback 1 versus pullback 2, read by reader A (interpullback comparison). The per-segment and per-frame analyses showed very high and significant correlation coefficients for the interobserver, intraobserver, and interpullback comparisons for the lumen area and lesion length (R ≥0.95 and p <0.001 in all cases). Accordingly, the Bland-Altman estimates of bias showed nonsignificant differences in the interobserver, intraobserver, and interpullback comparisons at all levels, with average biases never >0.150 mm(2) for the lumen area or 0.200 mm for the lesion length. In conclusion, coronary imaging using FD-OCT showed excellent reproducibility, with low intraobserver, interobserver, and interpullback variability for both lumen area and lesion length measurements in humans. Thus, FD-OCT can be proposed for precise analysis in the catheterization laboratory to guide decision making and in clinical trials focusing on imaging end points.


Assuntos
Doença das Coronárias/patologia , Vasos Coronários/patologia , Tomografia de Coerência Óptica/métodos , Angioplastia Coronária com Balão , Meios de Contraste , Angiografia Coronária , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Itália , Masculino , Estudos Prospectivos , Reprodutibilidade dos Testes , Software , Ácidos Tri-Iodobenzoicos
20.
Org Lett ; 14(6): 1540-3, 2012 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-22397622

RESUMO

An organocatalytic Friedel-Crafts alkylation of indoles with α,ß-unsaturated ketones was found to be efficiently accelerated under high-pressure conditions with a low loading of chiral primary amine salts with good yield and enantioselectivity up to 90%. This approach also allows, for the first time, selected indole derivatives containing quaternary stereogenic centers to be obtained from prochiral ß,ß-disubstituted enones with an enantioselectivity up to 80%.


Assuntos
Aminas/química , Indóis/química , Indóis/síntese química , Cetonas/química , Cetonas/síntese química , Alquilação , Catálise , Estrutura Molecular , Estereoisomerismo
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