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1.
Int J Offender Ther Comp Criminol ; : 306624X241240711, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546110

RESUMO

This article offers initial validation of the Good Lives Assessment of Domains (GLAD). Data were collected from an electronic survey of 1,484 American adults. Participants were recruited via paid research panels using quotas set to match the U.S. population on Age, Race/Ethnicity, Sex/Gender, Education, and Household Income. Participants responded to a set of items including 48 original items to assess perceptions of life satisfaction in the 11 domains described in the GLM and the 5 Satisfaction with Life Scale (SWLS) items. Factor Analysis indicated 45 final items that loaded onto 9 unique factors, with all loadings ranging between 0.391 and 0.854 with acceptable model fit (RMR = 0.070, CFI = 0.866, RMSEA = 0.063). Cronbach's Alphas demonstrated acceptable reliability, with items achieving alpha scores greater than .7 in all individual domains and for overall GLAD scores. The correlation between GLAD and SWLS scores was .610 (p < .001). An Independent samples T-test found a significant mean difference (t = 4.360, p < .001, mean difference = 8.15737) in GLAD scores between respondents who reported no engagement in crime and deviance and those who reported engagement in crime and deviance.

2.
Angew Chem Int Ed Engl ; 56(1): 193-197, 2017 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-27910251

RESUMO

Caged neurotransmitters, in combination with focused light beams, enable precise interrogation of neuronal function, even at the level of single synapses. However, most caged transmitters are, surprisingly, severe antagonists of ionotropic gamma-aminobutyric acid (GABA) receptors. By conjugation of a large, neutral dendrimer to a caged GABA probe we introduce a "cloaking" technology that effectively reduces such antagonism to very low levels. Such cloaked caged compounds will enable the study of the signaling of the inhibitory neurotransmitter GABA in its natural state using two-photon uncaging microscopy for the first time.


Assuntos
Dendrímeros/química , Antagonistas de Receptores de GABA-A/química , Neurônios/metabolismo , Imagem Óptica/métodos , Ácido gama-Aminobutírico/análogos & derivados , Animais , Células Cultivadas , Dendrímeros/metabolismo , Dendrímeros/farmacologia , Feminino , Antagonistas de Receptores de GABA-A/metabolismo , Antagonistas de Receptores de GABA-A/farmacologia , Masculino , Camundongos , Microscopia de Fluorescência/métodos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Fotólise , Fótons , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/farmacologia
3.
Sci Rep ; 5: 12119, 2015 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-26183486

RESUMO

Minimally invasive investigation of plant parts (root, stem, leaves, and flower) has good potential to elucidate the dynamics of plant growth, morphology, physiology, and root-rhizosphere interactions. Laboratory based absorption X-ray imaging and computed tomography (CT) systems are extensively used for in situ feasibility studies of plants grown in natural and artificial soil. These techniques have challenges such as low contrast between soil pore space and roots, long X-ray imaging time, and low spatial resolution. In this study, the use of synchrotron (SR) based phase contrast X-ray imaging (PCI) has been demonstrated as a minimally invasive technique for imaging plants. Above ground plant parts and roots of 10 day old canola and wheat seedlings grown in sandy clay loam soil were successfully scanned and reconstructed. Results confirmed that SR-PCI can deliver good quality images to study dynamic and real time processes such as cavitation and water-refilling in plants. The advantages of SR-PCI, effect of X-ray energy, and effective pixel size to study plant samples have been demonstrated. The use of contrast agents to monitor physiological processes in plants was also investigated and discussed.


Assuntos
Diagnóstico por Imagem/métodos , Plantas , Síncrotrons , Raios X , Meios de Contraste , Raízes de Plantas , Caules de Planta
4.
Eur J Neurosci ; 41(1): 5-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25471355

RESUMO

Caged compounds are widely used by neurophysiologists to study many aspects of cellular signaling in glia and neurons. Biologically inert before irradiation, they can be loaded into cells via patch pipette or topically applied in situ to a defined concentration; photolysis releases the caged compound in a very rapid and spatially defined way. As caged compounds are exogenous optical probes, they include not only natural products such neurotransmitters, calcium and IP3 but non-natural products such as fluorophores, drugs and antibodies. In this Technical Spotlight we provide a short introduction to the uncaging technique by discussing the nitroaromatic caging chromophores most widely used in such experiments [e.g. α-carboxy-ortho-nitrobenyl (CNB), dimethoxynitrobenzyl (DMNB), 4-methoxy-7-nitroindolinyl (MNI) and 4-carboxymethoxy-7-nitroindolinyl (CDNI)]. We show that recently developed caging chromophores [rutheniumbipyridial (RuBi) and 7-diethylaminocoumarin (DEAC)450] that are photolyzed with blue light (~ 430-480 nm range) can be combined with traditional nitroaromatic caged compounds to enable two-color optical probing of neuronal function. For example, one-photon uncaging of either RuBi-GABA or DEAC450-GABA with a 473-nm laser is facile, and can block nonlinear currents (dendritic spikes or action potentials) evoked by two-photon uncaging of CDNI-Glu at 720 nm. We also show that two-photon uncaging of DEAC450-Glu and CDNI-GABA at 900 and 720 nm, respectively, can be used to fire and block action potentials. Our experiments illustrate that recently developed chromophores have taken uncaging out of the 'monochrome era', in which it has existed since 1978, so as to enable multichromic interrogation of neuronal function with single-synapse precision.


Assuntos
Indicadores e Reagentes , Neurônios/fisiologia , Imagem Óptica/métodos , Animais , Processos Fotoquímicos
5.
ACS Chem Neurosci ; 5(1): 64-70, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24304264

RESUMO

We have synthesized photolabile 7-diethylamino coumarin (DEAC) derivatives of γ-aminobutyric acid (GABA). These caged neurotransmitters efficiently release GABA using linear or nonlinear excitation. We used a new DEAC-based caging chromophore that has a vinyl acrylate substituent at the 3-position that shifts the absorption maximum of DEAC to about 450 nm and thus is named "DEAC450". DEAC450-caged GABA is photolyzed with a quantum yield of 0.39 and is highly soluble and stable in physiological buffer. We found that DEAC450-caged GABA is relatively inactive toward two-photon excitation at 720 nm, so when paired with a nitroaromatic caged glutamate that is efficiently excited at such wavelengths, we could photorelease glutamate and GABA around single spine heads on neurons in brain slices with excellent wavelength selectivity using two- and one-photon photolysis, respectively. Furthermore, we found that DEAC450-caged GABA could be effectively released using two-photon excitation at 900 nm with spatial resolution of about 3 µm. Taken together, our experiments show that the DEAC450 caging chromophore holds great promise for the development of new caged compounds that will enable wavelength-selective, two-color interrogation of neuronal signaling with excellent subcellular resolution.


Assuntos
Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fótons , Ácido gama-Aminobutírico/análogos & derivados , Ácido gama-Aminobutírico/farmacologia , Animais , Química Encefálica , Cor , Hipocampo/citologia , Técnicas In Vitro , Camundongos , Técnicas de Patch-Clamp , Processos Fotoquímicos , Fotólise , Sinapses/efeitos dos fármacos , Ácido gama-Aminobutírico/química
6.
Tetrahedron ; 69(27-28)2013 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-24273349

RESUMO

Catalytic enantioselective methods for the generation of cyclopropanes has been of longstanding pharmaceutical interest. Chiral dirhodium(II) catalysts prove to be an effective means for the generation of diverse cyclopropane libraries. Rh2(R-DOSP)4 is generaally the most effective catalyst for asymmetric intermolecular cyclopropanation of methyl aryldiazoacetates with styrene. Rh2(S-PTAD)4 provides high levels of enantioinduction with ortho-substituted aryldiazoacetates. The less-established Rh2(R-BNP)4 plays a complementary role to Rh2(R-DOSP)4 and Rh2(S-PTAD)4 in catalyzing highly enantioselective cyclopropanation of 3- methoxy-substituted aryldiazoacetates. Substitution on the styrene has only moderate influence on the asymmetric induction of the cyclopropanation.

7.
J Am Chem Soc ; 135(42): 15948-54, 2013 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-24117060

RESUMO

Caged compounds are molecules rendered functionally inert by derivatization with a photochemical protecting group. We describe the design logic behind the development of a diethylaminocoumarin (DEAC) caging chromophore, DEAC450, that absorbs blue light strongly (ε450 = 43,000 M(-1) cm(-1)) and violet light 11-fold more weakly. The absorption minimum is in the wavelength range (340-360 nm) that is traditionally used for photolysis of many widely used nitroaromatic caged compounds (e.g., 4-carboxymethoxy-5,7-dinitroindolinyl(CDNI)-GABA). We used this chromophore to synthesize DEAC450-caged cAMP and found this probe was very stable toward aqueous hydrolysis in the electronic ground state but was photolyzed with a quantum efficiency of 0.78. When DEAC450-cAMP and CDNI-GABA where co-applied to striatal cholinergic interneurons, the caged compounds were photolyzed in an chromatically orthogonal manner using blue and violet light so as to modulate the neuronal firing rate in a bidirectional way.


Assuntos
Aminocumarinas/química , Cor , Cumarínicos/química , Luz , AMP Cíclico/química , Hidrólise , Estrutura Molecular , Processos Fotoquímicos , Ácido gama-Aminobutírico/química
8.
J Am Chem Soc ; 135(16): 5954-7, 2013 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-23577752

RESUMO

We have synthesized a 7-diethylaminocoumarin (DEAC) derivative that allows wavelength-selective two-photon uncaging at 900 nm versus 720 nm. This new caging chromophore, called DEAC450, has an extended π-electron moiety at the 3-position that shifts the absorption spectrum maximum of DEAC from 375 to 450 nm. Two-photon excitation at 900 nm was more than 60-fold greater than at 720 nm. Two-photon uncaging of DEAC450-Glu at 900 nm at spine heads on pyramidal neurons in acutely isolated brain slices generated postsynaptic responses that were similar to spontaneous postsynaptic excitatory miniature currents, whereas significantly higher energies at 720 nm evoked no currents. Since many nitroaromatic caged compounds are two-photon active at 720 nm, optically selective uncaging of DEAC450-caged biomolecules at 900 nm may allow facile two-color optical interrogation of bimodal signaling pathways in living tissue with high resolution for the first time.


Assuntos
Ácido Glutâmico/química , Neuroimagem/métodos , Animais , Química Encefálica , Cumarínicos/química , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Indicadores e Reagentes , Camundongos , Técnicas de Patch-Clamp , Fotólise , Células Piramidais/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Espectrofotometria Ultravioleta
9.
Dalton Trans ; 41(1): 251-60, 2012 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-22020444

RESUMO

Air and moisture stable homoleptic bis(diimidazolylidine)nickel(II) complexes, ([(diNHC)(2)Ni](2+)) 3a,b and their corresponding silver(I) 4a,b and palladium(II) 5a,b complexes were synthesized and characterized by NMR and single crystal X-ray analysis. The catalytic potential of complex 3a was assessed in Mizoroki-Heck and Suzuki-Miyaura coupling reactions. In the Suzuki-Miyaura coupling reaction, nickel precatalyst 3a was active for the coupling of aryl chlorides as well as aryl fluorides. The analogously synthesized Pd(II) complexes resulted in formation of (diNHC)PdCl(2) species which were not active for the coupling of aryl fluorides. For the Mizoroki-Heck reaction, it was found that aryl iodides could be activated in the absence of nickel or palladium precatalysts when using Na(2)CO(3) or NEt(3) as base while aryl iodides and aryl bromides could be activated in the Suzuki-Miyaura reaction sans precatalyst when K(3)PO(4) was used as base.

10.
Orthopedics ; 34(8): e374-7, 2011 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-21815579

RESUMO

Threaded and smooth pins are often used in orthopedic surgery. Although uncommon, injury to the soft tissues can and do occur, including nerve or vessel injury from aberrant pin placement. The purpose of this study was to compare the risk of nerve injury from threaded pins versus smooth guide pins due to: (1) past-point-drilling of the pin, or (2) entanglement of the pin with soft tissue. Past-point drilling was tested by a blindfolded participant drilling a 1.6-mm guide pin (terminally threaded or smooth) through a porcine femur until they felt they had drilled through the second cortex. The distance over-drilled was measured in millimeters. Twenty trials were randomly completed, 10 with each pin type. Entanglement of soft tissue was tested by placing the terminal portion of the guide pin on the nerve. Two drilling positions were tested: (1) drilling at 90° and (2) parallel to the nerve. The drill was run for 1 second and assessed for entanglement and magnitude of entanglement (measured in millimeters of nerve wrapped by the pin). Sixty trials were completed, 15 with each pin type, and in each of the 2 positions. The average past-point drilling depths were 4.6 and 16.9 mm for the smooth and threaded pins, respectively (P<.05). The mean nerve overwrapping was 0.45 and 4.7 mm, for the smooth and threaded pins, respectively (P<.05), drilled at 90° and 0.15 and 0.92 mm, respectively (P<.05) in the parallel position. In 13 of 60 trials with the smooth pin and 50 of 60 trials with the threaded pin, wrapping was observed (P<.05). This study demonstrates that it is difficult to determine by feel when the threaded pin has drilled through the second cortex of the bone, in contrast to the smooth pin. Furthermore, soft tissue entanglement is more likely and to a greater magnitude with threaded pins than with smooth.


Assuntos
Pinos Ortopédicos/efeitos adversos , Parafusos Ósseos/efeitos adversos , Fixação de Fratura/métodos , Complicações Intraoperatórias/etiologia , Animais , Fêmur , Fixação de Fratura/instrumentação , Humanos , Modelos Animais , Traumatismos dos Nervos Periféricos/etiologia , Desenho de Prótese , Lesões dos Tecidos Moles/etiologia , Suínos
11.
Tetrahedron Lett ; 52(26): 3345-3346, 2011 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-21779134

RESUMO

Procedures for the synthesis of thirty-six 5-methyl-3-(substituted)-[1,2,4]triazines have been described. These compounds were evaluated for antagonism at metabotropic glutamate receptor subtype 5. Two compounds, 5b and 3c, were determined to be low micromolar inhibitors of mGluR5.

12.
Environ Sci Technol ; 45(14): 6188-95, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21711052

RESUMO

XAFS spectroscopy has been used to determine the Ni species in particulate matter collected on quartz thimble filters in the stacks of eight residual (No. 6 fuel) oil-burning electric utility steam-generating units. Proper speciation of nickel in emitted particulate matter is necessary to correctly anticipate potential health risks. Analysis of the spectroscopic data using least-squares linear combination methods and a newly developed method specific for small quantities of Ni sulfide compounds in such emissions show that potentially carcinogenic Ni sulfide compounds are absent within the detection limits of the method (≤ 3% of the total Ni) in the particulate matter samples investigated. In addition to the major nickel sulfate phase (NiSO(4)·6H(2)O), lesser amounts of (Ni,Mg)O and/or NiFe(2)O(4) were also identified in most emission samples. On the basis of the results from these emission characterization studies, the appropriateness of the U.S. Environmental Protection Agency's assumption that the Ni compound mixture emitted from residual oil-fired power plants is 50% as carcinogenic as nickel subsulfide (Ni(3)S(2)) should be re-evaluated.


Assuntos
Poluentes Atmosféricos/análise , Cinza de Carvão/química , Monitoramento Ambiental/estatística & dados numéricos , Níquel/análise , Centrais Elétricas , Cinza de Carvão/análise , Análise dos Mínimos Quadrados , Níquel/química , Vapor , Espectroscopia por Absorção de Raios X
13.
Org Biomol Chem ; 9(11): 4276-86, 2011 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-21503289

RESUMO

In previous studies we showed that 3-(substituted phenylethynyl)-5-methyl[1,2,4]triazine analogues of MPEP were potent antagonists of glutamate-mediated mobilization of internal calcium in an mGluR5 in vitro efficacy assay. In the present study we report the synthesis and evaluation of six 3-(substituted biphenylethynyl)-5-methyl[1,2,4]triazines (5a-f), and five 3-(substituted phenoxyphenylethynyl)-5-methyltriazines (6a-e). Compound 2-(4-fluorophenyl-5-[2-(5-methyl[1,2,4]triazine-3-yl)ethynyl]benzonitrile (5f) with an IC(50) of 28.2 nM was the most potent analogue.


Assuntos
Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Triazinas/farmacologia , Animais , Células CHO , Cricetinae , Cricetulus , Humanos , Estrutura Molecular , Receptor de Glutamato Metabotrópico 5 , Estereoisomerismo , Relação Estrutura-Atividade , Triazinas/síntese química , Triazinas/química
14.
ACS Med Chem Lett ; 2(12): 882-884, 2011 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-22523618

RESUMO

In an effort to discover potent and selective metabotropic glutamate receptor subtype 5 (mGluR5) antagonists, 15 tetrahydropyrimidinone analogues of 1-(3-chlorophenyl)-3-(1-methyl-4-oxo-4,5-dihydro-1H-imidazol-2-yl)-urea (fenobam) were synthesized. These compounds were evaluated for antagonism of glutamate-mediated mobilization of internal calcium in an mGluR5 in vitro efficacy assay. The IC(50) value for 1-(3-chlorophenyl)-3-(1-methyl-4-oxo-1,4,5,6-tetrahydropyridine)urea (4g) was essentially identical to that of fenobam.

15.
Org Lett ; 10(4): 573-6, 2008 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-18215048

RESUMO

The reaction of benzofuranyldiazoacetates with 1,3-dienes catalyzed by the dirhodium tetracarboxylate Rh2(R-DOSP)4, generates formal [4+3] cycloadducts with >94% de and 91-98% ee. The reaction proceeds by a tandem cyclopropanation/Cope rearrangement followed by a stereoselective tautomerization. This methodology was extended to a formal synthesis of (+)-frondosin B.


Assuntos
Alcenos/química , Benzofuranos/química , Compostos Heterocíclicos de 4 ou mais Anéis/síntese química , Catálise , Compostos Heterocíclicos de 4 ou mais Anéis/química , Estrutura Molecular , Estereoisomerismo
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