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1.
Org Biomol Chem ; 22(20): 4123-4134, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38700442

RESUMO

A family of stilbenyl-azopyrroles compounds 2a-d and 3a-d was efficiently obtained via a Mizoroki-Heck C-C-type coupling reaction between 2-(4'-iodophenyl-azo)-N-methyl pyrrole (1a) and different vinyl precursors. The influence of the π-conjugated backbone and the effect of the pyrrole moiety were correlated with their optical properties. Studies via UV-Visible spectrophotometry revealed that the inclusion of EWG or EDG favors a red-shift of the main absorption band in these azo compounds compared with their non-substituted analogues. Furthermore, there is a clear influence between the half-life of the Z isomer formed by irradiation with white light and the push-pull behavior of the molecules. In several cases, the stilbenyl-azopyrroles led to the formation of J-type aggregates in binary MeOH : H2O solvents, which are of interest for water compatible applications.

2.
Org Biomol Chem ; 18(8): 1657-1670, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32048680

RESUMO

A new family of push-pull biphenyl-azopyrrole compounds 3b-g and 4b-d was efficiently obtained via a Suzuki cross-coupling reaction between 2-(4'-iodophenyl-azo)-N-methyl pyrrole (1a) or 3-(4'-iodophenyl-azo)-1,2,5-trimethyl pyrrole (2a) and 4'-substituted phenyl boronic acids in excellent yields. The influence of the π-biphenyl backbone and pyrrole pattern substitution was correlated with their optical properties. Solvatochromic studies via UV-visible spectrophotometry revealed that the inclusion of a 4'-nitro-biphenyl fragment favors a red-shift of the main absorption band in these azo compounds compared with their non-substituted analogues. Likewise, optical band-gaps were estimated by means of electronic absorption spectra and correlated with TD-DFT studies. The pyrrole pattern substitution and the π-conjugated backbone exhibit a clear influence on their thermal isomerization kinetics at room temperature. In all cases, biphenylazo-pyrrole compounds lead to the formation of J-type aggregates in binary MeOH : H2O solvents. Under these conditions, compounds 3b-c undergo a water-assisted cis-to-trans isomerization at room temperature.

3.
Neurobiol Learn Mem ; 127: 17-26, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26656274

RESUMO

Intracranial self-stimulation (ICSS) of the lateral hypothalamus (LH) is involved in the activation of neuroanatomical systems that are also associated with the processing of natural and other artificial rewarding stimuli. Specific components of this behavior (hedonic impact, learning, and motor behavior) may involve changes in different neurotransmitters, such as dopamine and opioids. In this study, quantitative autoradiography was used to examine changes in mu-opioid and D1/D2-dopamine receptor expression in various anatomical regions related to the motor and mesolimbic reward systems after intracranial self-stimulation of the LH. Results of the behavioral procedure and subsequent radiochemical assays show selective changes in D1 but not D2 or mu receptors in Accumbens-Shell, Ventral Pallidum, Caudate-Putamen, and Medial Globus Pallidus. These findings are discussed in relation to the different psychobiological components of the appetitive motivational system, identifying some dissociation among them, particularly with respect to the involvement of the D1-dopamine subsystem (but not D2 or mu receptors) in goal-directed behaviors.


Assuntos
Encéfalo/fisiologia , Região Hipotalâmica Lateral/fisiologia , Sistema Límbico/fisiologia , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores Opioides mu/metabolismo , Animais , Autorradiografia , Encéfalo/metabolismo , Estimulação Elétrica , Sistema Límbico/metabolismo , Masculino , Ratos Wistar , Autoestimulação
4.
Dalton Trans ; 52(9): 2722-2734, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36748862

RESUMO

The synthesis of a series of ferrocenylvinylketenes as stable η4-[Fe(CO)3] complexes (3a-f) was successfully accomplished through the reaction of η2-[Fe(CO)4] complexes under mild carbonylation conditions. The reactivity of 3a-f under thermal conditions afforded the unexpected formation of a novel family of (µ2,η3-allyl-η5-oxapentadienyl)diiron pentacarbonyl complexes 5a-f proposed to be formed by a sequence metathesis-haptotropic rearrangement between the starting η4-vinylketene iron(0) complex 3 and a η4-vinylcarbene iron(0) complex trapped in situ after a reversible carbonylation process favored by the thermal conditions. An electron density distribution analysis (EDD) of 5e using high-resolution X-ray diffraction data in combination with the DFT framework was performed to understand the electronic communication between the two iron fragments.

5.
Inorg Chem ; 49(9): 4109-16, 2010 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-20380385

RESUMO

New lanthanide complexes with 4,5-bis(diphenyl)phosphoranyl-1,2,3-triazolate (L(-)), LnL(3).nH(2)O (1-8) and LnL(3)(phen).nH(2)O (9-16) (Ln = La, Ce, Nd, Sm, Eu, Gd, Tb, Er), have been prepared and spectroscopically characterized. The structures of LnL(3).nH(2)O (Ln = La, Ce, Nd, Sm and Gd) were determined by X-ray crystallography. The metal centers exhibit a distorted trigonal dodecahedron coordination environment with two symmetrically O,O-bidentate ligands and one unsymmetrically O,N- ligand attached to the metal; two oxygen atoms from neighboring dimethyl sulfoxide (DMSO) molecules complete the coordination sphere. This unsymmetrical ligand coordination behavior was also identified in solution through (31)P{(1)H} NMR studies. Photoluminescence spectroscopy experiments in CH(2)Cl(2) for both types of complexes containing Eu(III) (6, 14) and Tb(III) (7, 15) exhibit strong characteristic red and green emission bands for Eu(III) and Tb(III), respectively. Furthermore, NdL(3) (phen).5H (2)O (11) displays emission in the near-infrared spectral region ((4)F(3/2) --> (4)F(9/2) at 872 nm and (4)F(3/2) --> (4)F(11/2) at 1073 nm). The complexes containing 1,10-phenantroline exhibit higher quantum yields upon excitation at 267 nm, indicating that this auxiliary ligand promotes the luminescence of the complexes; however, luminescence lifetimes (tau) in this case are shorter than those of the LnL(3).nH(2)O series.


Assuntos
Elementos da Série dos Lantanídeos/química , Compostos Organometálicos/síntese química , Fenantrolinas/química , Triazóis/química , Cristalografia por Raios X , Ligantes , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/química
6.
J Nat Prod ; 73(11): 1969-72, 2010 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-20942442

RESUMO

Three new lupane-type triterpenes, lippiolide (1), lippiolidolic acid (2), and lippiolic acid (3), were isolated from aerial parts of Lippia mexicana. Compounds 1 and 2 exhibited a δ-lactone at ring E. The known cycloartane triterpene 5 was also isolated. The structures of these compounds were established on the basis of spectroscopic data and chemical reactions, and the structure of compound 1 was confirmed by X-ray diffraction analysis. Anti-inflammatory activity of compounds 1, 3, and 5 was evaluated in the TPA-induced ear mouse edema model. Lupanes 1 and 3 were more active than cycloartane 5.


Assuntos
Anti-Inflamatórios/isolamento & purificação , Lactonas/química , Lippia/química , Triterpenos/química , Triterpenos/isolamento & purificação , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Cristalografia por Raios X , Modelos Animais de Doenças , Edema/induzido quimicamente , Edema/tratamento farmacológico , Camundongos , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Estereoisomerismo , Triterpenos/farmacologia
7.
Eura Medicophys ; 43(1): 37-47, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17159742

RESUMO

AIM: Changes in the amplitude of Hoffmann reflex (H-reflex) may reflect variations in the characteristics of the largely monosynaptic circuitry that is explored and are a possible target for diagnostic and physical therapeutic intervention. However, previous attempts to induce predictable changes in the H-reflex amplitude by transcutaneous electrical nervous stimulation (TENS) have generally failed. Previous workers applied fixed frequency in the low- (2-5 Hz) or in the high- (100 Hz) field, but they did not attempt to vary frequency and/or impulse duration in time. METHODS: We evaluated the effect of a new type of painless electric stimulation, i.e. frequency rhythmic electrical modulation system (FREMS). FREMS is characterized by the use of transcutaneous electric pulses with sequentially modulated frequency (f: 1-39 Hz) and width (w: 10-40 micro s) at constant, perceptive threshold voltage (approximately 150 V). FREMS was applied at the abductor hallucis muscle (AHM), as conditioning stimulus of the H-reflex which was recorded ipsilaterally at the soleus muscle, according to the classic method, in 10 normal volunteers (age range 21-40 years). RESULTS: H-reflex amplitude was substantially decreased (-50%) during FREMS and H-reflex amplitude variations were influenced by w/f variation in time during FREMS subphase C in a predictable way (r(2)=0.43; P<0.001). Our results suggest an effective ability of FREMS to modulate H reflex amplitude. CONCLUSIONS: The ability to achieve large and predictable changes of the H-reflex amplitude simply by modulating both frequency and duration of a conditioning painless electrical stimulation offers new possibilities for the treatment of diseases characterized by motoneuron excitability abnormalities.


Assuntos
Músculo Esquelético/inervação , Reflexo Anormal/fisiologia , Estimulação Elétrica Nervosa Transcutânea/métodos , Potenciais de Ação/fisiologia , Adulto , Análise de Variância , Eletromiografia/instrumentação , Eletromiografia/métodos , Humanos , Neurônios Motores/fisiologia , Nervos Espinhais/fisiologia , Transmissão Sináptica/fisiologia , Nervo Tibial/fisiologia , Estimulação Elétrica Nervosa Transcutânea/instrumentação
8.
Dalton Trans ; 46(5): 1510-1519, 2017 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-28091644

RESUMO

An efficient method to obtain chiral 1,2-disubstituted ferrocenyl ligands has been developed. The introduction of planar chirality was accomplished by using 2-thiazoline as an ortho-directing lithiation group, and moreover, these kinds of ligands possess a central chirality from the amino alcohol used in their synthesis. The X-ray analysis and DFT calculations confirmed the diastereoselectivity of ortho-lithiation and the configuration of the planar chirality. The ability of these new bidentate [N,S]-ferrocene ligands to act in Pd-catalyzed asymmetric allylic alkylation has also been demonstrated and compared with their oxazoline counterparts.

9.
ISA Trans ; 45(1): 35-44, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16480108

RESUMO

This paper presents a simple but effective method for finding a robust output feedback controller via a random search algorithm. The convergence of this algorithm can be guaranteed. Moreover, the probability to find a solution as well as the number of random trials can be estimated. The robustness of the closed-loop system is improved by the minimization of a given cost function reflecting the performance of the controller for a set of plants. Simulation studies are used to demonstrate the effectiveness of the proposed method.

10.
J Med Chem ; 29(4): 589-91, 1986 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3959034

RESUMO

The (-)-S isomer of 5-benzoyl-1,2-dihydro-3H-pyrrolo[1,2-alpha]pyrrole-1-carboxylic acid is about 60 times more potent than the (+)-R isomer in the carrageenan edema test and ca. 230 times more active than the (+)-R isomer in the mouse phenylquinone writhing assay.


Assuntos
Analgésicos , Anti-Inflamatórios , Pirróis , Tolmetino , Analgésicos/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Cetorolaco , Camundongos , Conformação Molecular , Ratos , Estereoisomerismo , Tolmetino/análogos & derivados
11.
Virchows Arch ; 434(3): 259-62, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10190308

RESUMO

A 35-year-old man suffered simultaneously from nodular sclerosis Hodgkin's disease (HD), Langerhans' cell histiocytosis and multiple myeloma (MM). There was no prior history of irradiation or chemotherapy, and clinically the lymphoma was confined to cervical lymph nodes. Immunohistochemically, neoplastic lymphoma cells reacted with CD15 and CD30 markers. The patient's bone marrow exhibited a diffuse infiltration by rather atypical plasma cells showing kappa immunoglobulin light-chain restriction. At 14 months after the diagnosis, after autologous bone marrow transplantation, the clinical evolution is favourable with complete remission of the diseases. This is the first time that the coexistence of these three haematological disorders has been discussed, and only the fourth documented case of simultaneous HD and MM. Speculations about the significance of this finding are discussed.


Assuntos
Histiocitose de Células de Langerhans/complicações , Doença de Hodgkin/complicações , Imunoglobulinas/metabolismo , Mieloma Múltiplo/complicações , Adulto , Histiocitose de Células de Langerhans/metabolismo , Histiocitose de Células de Langerhans/patologia , Doença de Hodgkin/metabolismo , Doença de Hodgkin/patologia , Humanos , Linfonodos/patologia , Masculino , Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Plasmócitos/metabolismo
12.
Phytochemistry ; 58(5): 751-8, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11672740

RESUMO

Reinvestigation of the fermentation broth and mycelium of the coprophilous fungus Guanomyces polythrix, grown in static conditions, led to the isolation of several phytotoxic compounds, including two new naphthopyranone derivatives, namely (2S, 3R)-5-hydroxy-6,8-dimethoxy-2,3-dimethyl-2,3-dihydro-4H-naphtho[2,3-b]-pyran-4-one and (2S, 3R)-5-hydroxy-6,8,10-trimethoxy-2,3-dimethyl-2,3-dihydro-4H-naphtho[2,3-b]-pyran-4-one. The structures of the new compounds were established by spectral and chiroptical methods. In addition, the structure of 8-hydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylic acid methyl ester was unambiguously determined by X-ray analysis. The isolates caused significant inhibition of radicle growth of two weed seedlings (Amaranthus hypochondriacus and Echinochloa crusgalli) and interacted with both spinach and bovine brain calmodulins.


Assuntos
Amaranthus/efeitos dos fármacos , Fungos/química , Naftalenos/metabolismo , Naftalenos/farmacologia , Pironas/metabolismo , Pironas/farmacologia , Amaranthus/crescimento & desenvolvimento , Calmodulina/metabolismo , Cristalografia por Raios X , Fermentação/fisiologia , Herbicidas/química , Herbicidas/isolamento & purificação , Herbicidas/farmacologia , Conformação Molecular , Naftalenos/química , Naftalenos/isolamento & purificação , Ligação Proteica , Pironas/isolamento & purificação
13.
Steroids ; 63(11): 556-64, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9830681

RESUMO

The epimers 17 beta-amino-1,3,5(10)-estratrien-3-ol and 17 alpha-amino-1,3,5(10)-estratrien-3-ol were synthesized. 17 beta-Amino-1,3,5(10)-estratrien-3-ol was prepared by catalytic hydrogenation of the estrone-oxime. The 17 alpha-amino epimer was obtained from estradiol, via tosylate, followed by nucleophilic displacement by sodium azide and subsequent reduction with LiAlH4. They were characterized by spectroscopic methods. Determination of the crystal structures of 3-(toluene-4-sulfonyloxy)-17 alpha-1,3,5(10)-estratriene, 3-(toluene-4-sulfonyloxy)-17-alpha-amino,1,3,5(10)-estratriene hydrochloride, 17 beta-acetylamino-1,3,5(10)-estratriene-3-ol, and 3-acetoxy-17 beta-acetylamino-1,3,5(10)-estratriene enabled us to characterize the structure of the 17 alpha and 17 beta amino epimers for the first time.


Assuntos
Congêneres do Estradiol/química , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular
14.
Steroids ; 45(2): 151-7, 1985 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3841424

RESUMO

The synthesis and molecular structure of prolame, N-(3-hydroxy-1,3,5(10)-estratrien-17 beta-yl)-3-hydroxypropylamine, is described. It was characterized by ir, nmr, mass spectrometry and chemical analysis. The crystal structure of this compound was determined by single-crystal x-ray diffraction. Prolame belongs to space group P212121. Cell dimensions are: a = 8.356(2), b = 13.343(4) and c = 16.119(4) A. Z = 4; R = 4.1%.


Assuntos
Anticoagulantes/síntese química , Congêneres do Estradiol/síntese química , Estrenos/síntese química , Modelos Moleculares , Conformação Molecular , Difração de Raios X
15.
J Inorg Biochem ; 80(1-2): 173-6, 2000 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-10885482

RESUMO

Kinetics of the oxidation of cysteine to cystine by four V(V) oxo diperoxo complexes [VO(O2)2L] possessing insulin mimetic activity, where L = oxalate(oxa), picolinate (pic), bipyridil (bipy), phenanthroline(phen), were performed in water at 10 degrees C by the UV or stopped-flow technique. 51V NMR spectra indicate that oxa undergoes a total ligand dissociation differently from pic, bipy and phen which hold their ligands also in solution. The observed reactivity is deeply affected by the identity of the ligand. The process seems to require coordination of the cysteine to the metal, followed by oxidation within the coordination sphere. In this respect phen and bipy make the coordination of cysteine much easier than oxa and pic. It is suggested, also on the basis of some preliminary observations concerning the oxidation of C6H5CH2SH, that the oxidation process is triggered by an electron transfer step. The rate of this step would be higher for oxa and pic than for phen and bipy. The observation that the oxidative ability of these vanadium peroxo complexes is dependent upon the nature of the ligands might match the analogous finding that their insulin mimetic activity is also modulated by the ligand identities.


Assuntos
Cisteína/metabolismo , Insulina/farmacologia , Vanadatos/farmacologia , Ligantes , Espectroscopia de Ressonância Magnética , Modelos Químicos , Estrutura Molecular , Fenantrolinas/química , Relação Estrutura-Atividade
16.
Surg Endosc ; 15(9): 924-7, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11605107

RESUMO

We report our learning experience in simulated and real surgical tasks with a new voice-controlled robotic endoscope manipulator: an industrial robot with the tool-holder arm modified to support the optic and camera. The manipulator control-card programs have been rewritten to meet the needs of endoscopic surgeons. For this preliminary work, systems engineers with an additional monitor monitored, recorded, and compared the percentage effectiveness and precision of the responses of the robotic and human assistant to successive oral commands during the several different experimental surgical tasks. Simultaneously, to help develop this voice-commanded system for future, more precise robotic manipulation of surgical instruments, they measured the cartesian and spherical coordinates of successive positions of the optic. In unexpectedly difficult experimental conditions, the tireless robot proved more precise and effective than the demonstrably fatigable human: the steadier screen images of the robotic manipulations helped the surgeon tie knots in 7-0 sutures.


Assuntos
Endoscopia/métodos , Robótica/instrumentação , Animais , Desenho de Equipamento/métodos , Humanos , Modelos Animais , Robótica/métodos , Estômago/cirurgia , Técnicas de Sutura , Suínos , Interface Usuário-Computador , Cirurgia Vídeoassistida/instrumentação , Cirurgia Vídeoassistida/métodos , Voz
17.
Am Surg ; 61(11): 940-2, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7486420

RESUMO

Pseudoaneurysms of the splenic artery have been well described in association with pancreatic pseudocysts secondary to pancreatitis. We present a case of a ruptured splenic artery pseudoaneurysm 14 years after splenectomy for trauma which, at that time, was complicated by a subphrenic abscess.


Assuntos
Aneurisma Roto/diagnóstico por imagem , Artéria Esplênica , Aneurisma Roto/complicações , Aneurisma Roto/cirurgia , Feminino , Hemorragia Gastrointestinal/etiologia , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Radiografia , Ruptura Espontânea , Esplenectomia , Ruptura Esplênica/cirurgia , Abscesso Subfrênico/complicações , Fatores de Tempo
18.
Am Surg ; 60(11): 889-91, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7978688

RESUMO

Compression of the common bile duct by a stone impacted in the cystic duct is an uncommon cause of obstructive jaundice. We present a case study and review of the literature pertaining to the presentation, diagnosis, and surgical treatment of Mirizzi Syndrome.


Assuntos
Colelitíase/complicações , Colestase Extra-Hepática/etiologia , Ducto Cístico/patologia , Ducto Hepático Comum/patologia , Colangite/etiologia , Colecistite/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome
19.
J Pediatr Endocrinol Metab ; 14 Suppl 5: 1271-5; discussion 1297-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11964022

RESUMO

Autoimmune thyroid diseases (AITD) are known to be clustered in families, but to what extent this occurs in childhood and adolescence is not well defined. In order to establish the prevalence of AITD in the siblings of affected children and adolescents, we examined 73 siblings from 66 families selected on the basis of a pediatric index patient. Sixty-six families, including a total of 146 offspring, were selected on the basis of diagnosis of chronic lymphocytic thyroiditis (CLT) (n = 55) or Graves' disease (GD) (n = 11). Among the 73 siblings examined, 20 new cases of CLT (27%) were detected. L-Thyroxine therapy was required in 4/20. History of AITD was recorded in 24/66 mothers (36%), and in two fathers. Overall in these families, considering both the index patients and the new patients, 86/141 (61%) children and adolescents were affected with AITD, with a female/male ratio of 3.3:1. Our study confirms that AITD clusters in families with a high prevalence in the siblings of affected children and adolescents. These children should be followed in order to avoid undiagnosed hypothyroidism. Prospective studies are warranted to identify predictive factors for overt thyroid disease.


Assuntos
Tireoidite Autoimune/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Humanos , Itália/epidemiologia , Masculino , Hormônios Tireóideos/sangue , Tireoidite Autoimune/diagnóstico por imagem , Tireoidite Autoimune/genética , Tiroxina/sangue , Tiroxina/uso terapêutico , Ultrassonografia
20.
Surg Laparosc Endosc Percutan Tech ; 9(3): 190-3, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10803998

RESUMO

We treated a series of 30 patients who had a Nyhus type II, III, or IV inguinal hernia without associated pathology by laparoscopic surgery using 2-mm surgical instruments and a modified preperitoneal Dulucq technique. A 30 degrees optic was used, and the repair was reinforced by an accordion-folded, polypropylene mesh introduced through a 10-mm optic needleport. There were no postoperative complications, and all patients were discharged 24 hours after operation. At 6 months there has been no recurrence of hernia. It was evident that the 2-mm procedure produced less surgical trauma.


Assuntos
Hérnia Inguinal/cirurgia , Laparoscopia , Humanos , Laparoscopia/métodos , Masculino , Instrumentos Cirúrgicos , Telas Cirúrgicas , Fatores de Tempo
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