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1.
Artigo em Inglês | MEDLINE | ID: mdl-28295762

RESUMO

The role of spirituality on the psychological health was mostly investigated through studies conducted in terminally ill patients. However, there are not studies investigating the role of religious and spiritual beliefs on psychological state and on burden dimensions in caregivers. The purpose of this study was to investigate the association between spirituality, burden, and psychological state in caregivers of terminally ill cancer patients. Two hundred caregivers of terminally ill patients with cancer were interviewed using Prolonged Grief Disorder 12 (PG-12), Hamilton Anxiety Rating Scale (HAM-A), Hamilton Depression Scale (HAM-D), Caregiver Burden Inventory (CBI) and System of Belief Inventory (SBI-15R). The caregiver burden was positively correlated with anxiety, depression and PG-12 scores. The intrinsic spirituality was a significant predictor of the time-dependence burden (positively associated); and of the emotional burden (negatively associated). In caregivers of terminally ill cancer patients, higher levels of intrinsic spirituality predicted a higher amount of time devote to caregiving, and also protected against the emotional distress linked to providing assistance.


Assuntos
Cuidadores/psicologia , Efeitos Psicossociais da Doença , Neoplasias/psicologia , Espiritualidade , Assistência Terminal/psicologia , Adaptação Psicológica , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doente Terminal
2.
Nature ; 462(7273): 620-3, 2009 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-19935645

RESUMO

Super-massive black holes in active galaxies can accelerate particles to relativistic energies, producing jets with associated gamma-ray emission. Galactic 'microquasars', which are binary systems consisting of a neutron star or stellar-mass black hole accreting gas from a companion star, also produce relativistic jets, generally together with radio flares. Apart from an isolated event detected in Cygnus X-1, there has hitherto been no systematic evidence for the acceleration of particles to gigaelectronvolt or higher energies in a microquasar, with the consequence that we are as yet unsure about the mechanism of jet energization. Here we report four gamma-ray flares with energies above 100 MeV from the microquasar Cygnus X-3 (an exceptional X-ray binary that sporadically produces radio jets). There is a clear pattern of temporal correlations between the gamma-ray flares and transitional spectral states of the radio-frequency and X-ray emission. Particle acceleration occurred a few days before radio-jet ejections for two of the four flares, meaning that the process of jet formation implies the production of very energetic particles. In Cygnus X-3, particle energies during the flares can be thousands of times higher than during quiescent states.

3.
Reumatismo ; 67(3): 97-102, 2015 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-26876188

RESUMO

The aim of this study was to assess circulating levels of reactive oxygen metabolites (ROMs) as a marker of oxidative stress in rheumatoid arthritis (RA) patients during an anti-tumor necrosis factor alpha (TNF-α) treatment. We enrolled 40 patients with RA (36 females; age 53 ± 13 yrs) treated with different subcutaneously administered TNF-α inhibitors. The oxidative status was determined on the basis of plasma samples taken before, at 24 and 52 weeks of the anti-TNF-α treatment. Hydroperoxide levels were measured using the d-ROMs test, a useful clinically proven oxidative stress marker. During the anti-TNF-α therapy, we observed a significant reduction in serum ROMs levels in RA patients from 33.2 ± 10 mg H2O2/L at baseline to 29.5 ± 7 and 29.3 ± 9 mg H2O2/L, at 24 and 52 weeks, respectively (p<0.05). We also identified a significant correlation between the oxidative stress status and the disease activity score on 28 joints/C-reactive protein and health assessment questionnaire disability index. The results of our study demonstrate that a good control of the disease with anti-TNF-α agents can reduce oxidative stress in RA patients. However, further studies of larger patient cohorts are needed to confirm these preliminary data.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Proteína C-Reativa/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Adulto , Idoso , Artrite Reumatoide/sangue , Biomarcadores/sangue , Feminino , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Pessoa de Meia-Idade , Oxidantes/metabolismo
4.
Org Biomol Chem ; 12(28): 5235-42, 2014 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-24920241

RESUMO

Herein, we report optically pure modified acyclic nucleosides as ideal probes for aptamer modification. These new monomers offer unique advantages in exploring the role played in thrombin inhibition by a single residue modification at key positions of the TBA structure.


Assuntos
Antitrombinas/síntese química , Aptâmeros de Nucleotídeos/síntese química , Nucleosídeos/química , Trombina/antagonistas & inibidores , Antitrombinas/química , Aptâmeros de Nucleotídeos/química , Dicroísmo Circular , Quadruplex G , Modelos Moleculares , Mimetismo Molecular , Rotação Ocular , Estereoisomerismo , Termodinâmica , Trombina/química
5.
Phys Rev Lett ; 106(1): 018501, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21231775

RESUMO

Strong electric discharges associated with thunderstorms can produce terrestrial gamma-ray flashes (TGFs), i.e., intense bursts of x rays and γ rays lasting a few milliseconds or less. We present in this Letter new TGF timing and spectral data based on the observations of the Italian Space Agency AGILE satellite. We determine that the TGF emission above 10 MeV has a significant power-law spectral component reaching energies up to 100 MeV. These results challenge TGF theoretical models based on runaway electron acceleration. The TGF discharge electric field accelerates particles over the large distances for which maximal voltages of hundreds of megavolts can be established. The combination of huge potentials and large electric fields in TGFs can efficiently accelerate particles in large numbers, and we reconsider here the photon spectrum and the neutron production by photonuclear reactions in the atmosphere.

6.
Eur Biophys J ; 40(11): 1237-45, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21750910

RESUMO

We evaluated the potential of tryptophan (Trp) phosphorescence spectroscopy for investigating conformational states of proteins involved in interaction with nanoparticles. Characterization of protein-nanoparticle interaction is crucial in assessing biological hazards related to use of nanoparticles. We synthesized glutathione-coated CdS quantum dots (GSH-CdS), which exhibited an absorption peak at 366 nm, indicative of 2.4 nm core size. Chemical analysis of purified GSH-CdS suggested an average molecular formula of GSH18S56Cd60. Investigations were conducted on model proteins varying in terms of isoelectric point, degree of burial of the Trp probe, and quaternary structure. GSH-CdS fluorescence measurements showed improvement in nanoparticle quantum yield induced by protein interaction. Trp phosphorescence was used to examine the possible perturbations in the protein native fold induced by GSH-CdS. Phosphorescence lifetime measurements highlighted significant conformational changes in some proteins. Despite their small size, GSH-CdS appeared to interact with more than one protein molecule. Rough determination of the affinity of GSH-CdS for proteins was derived from the change in phosphorescence lifetime at increasing nanoparticle concentrations. The estimated affinities were comparable to those observed for specific protein-ligand interactions and suggest that protein-nanoparticle interaction may have a biological impact.


Assuntos
Compostos de Cádmio/química , Glutationa/química , Glutationa/farmacologia , Medições Luminescentes , Proteínas/química , Pontos Quânticos , Sulfetos/química , Triptofano/química , Animais , Geobacillus stearothermophilus/enzimologia , Modelos Moleculares , Conformação Proteica/efeitos dos fármacos , Coelhos
7.
Food Microbiol ; 28(2): 311-20, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21315989

RESUMO

Models on Clostridium perfringens growth which have been published to date have all been deterministic. A probabilistic model describing growth under non-isothermal conditions was thus proposed for predicting C. perfringens growth in beef-in-sauce products cooked and distributed in a French hospital. Model parameters were estimated from different types of data from various studies. A Bayesian approach was proposed to model the overall uncertainty regarding parameters and potential variability on the 'work to be done' (h(0)) during the germination, outgrowth and lag phase. Three models which differed according to their description of this parameter h(0) were tested. The model with inter-curve variability on h(0) was found to be the best one, on the basis of goodness-of-fit assessment and validation with literature data on results obtained under non-isothermal conditions. This model was used in two-dimensional Monte Carlo simulations to predict C. perfringens growth throughout the preparation of beef-in-sauce products, using temperature profiles recorded in a hospital kitchen. The median predicted growth was 7.8×10(-2) log(10) cfu·g(-1) (95% credibility interval [2.4×10(-2), 0.8]) despite the fact that for more than 50% of the registered temperature profiles cooling steps were longer than those required by French regulations.


Assuntos
Clostridium perfringens/crescimento & desenvolvimento , Conservação de Alimentos/métodos , Produtos da Carne/microbiologia , Modelos Biológicos , Teorema de Bayes , Contagem de Colônia Microbiana , Qualidade de Produtos para o Consumidor , Culinária/métodos , Manipulação de Alimentos/métodos , Humanos , Cinética , Método de Monte Carlo , Valor Preditivo dos Testes , Temperatura
8.
Infez Med ; 17(4): 240-3, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20046105

RESUMO

A case of prosthetic valve endocarditis due to methicillin susceptible Staphylococcus aureus (MSSA) with cerebral metastatic seeding is described. The patient is a 61 year old man with diabetes mellitus, chronic renal failure and previous bacterial endocarditis. Despite appropriate MSSA therapy, the patient was eventually cured with the introduction of linezolid, without needing surgical intervention.


Assuntos
Acetamidas/uso terapêutico , Anti-Infecciosos/uso terapêutico , Valva Aórtica/cirurgia , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/etiologia , Próteses Valvulares Cardíacas/efeitos adversos , Embolia Intracraniana/tratamento farmacológico , Staphylococcus aureus Resistente à Meticilina , Oxacilina/uso terapêutico , Oxazolidinonas/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Teicoplanina/uso terapêutico , Humanos , Linezolida , Masculino , Resultado do Tratamento
9.
Aust Dent J ; 2018 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-29770451

RESUMO

Many women believe that their dental condition deteriorated during pregnancy or as a result of having children. Epidemiological studies have reported an association between higher parity and tooth loss, and higher parity and periodontal attachment loss. Several possible explanations for this association exist. First, hormonal changes during pregnancy affect the immune response to bacterial plaque and drive vascular and gingival changes that may contribute to heightened gingival inflammation. These changes are transient, without irreversible loss of periodontal attachment, and post-partum resolution can be expected for most women. For women with destructive periodontal disease, the effects of pregnancy and parity are unclear. Second, it is also plausible that parity and socioeconomic position (SEP) have shared risk factors, increasing the incidence of disease or influencing its management. Education, one aspect of SEP, is an important determining factor for women's fertility rate, with a gradient of fewer children with higher educational attainment. Higher levels of education are also favourably associated with behaviours conducive to oral health, and a lower incidence of damaging health behaviours. Thus, the potential for confounding is considerable. This review examines the literature on the association between pregnancy, parity and periodontal health, and explores sociobehavioural mechanisms for the observed association.

10.
Leukemia ; 32(4): 996-1002, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29158558

RESUMO

Arginine methyltransferases critically regulate cellular homeostasis by modulating the functional outcome of their substrates. The protein arginine methyltransferase 5 (PRMT5) is an enzyme involved in growth and survival pathways promoting tumorigenesis. However, little is known about the biologic function of PRMT5 and its therapeutic potential in multiple myeloma (MM). In the present study, we identified and validated PRMT5 as a new therapeutic target in MM. PRMT5 is overexpressed in patient MM cells and associated with decreased progression-free survival and overall survival. Either genetic knockdown or pharmacological inhibition of PRMT5 with the inhibitor EPZ015666 significantly inhibited growth of both cell lines and patient MM cells. Furthermore, PRMT5 inhibition abrogated NF-κB signaling. Interestingly, mass spectrometry identified a tripartite motif-containing protein 21 TRIM21 as a new PRMT5-partner, and we delineated a TRIM21-dependent mechanism of NF-κB inhibition. Importantly, oral administration of EPZ015666 significantly decreased MM growth in a humanized murine model of MM. These data both demonstrate the oncogenic role and prognostic relevance of PRMT5 in MM pathogenesis, and provide the rationale for novel therapies targeting PRMT5 to improve patient outcome.


Assuntos
Mieloma Múltiplo/metabolismo , Mieloma Múltiplo/patologia , Proteína-Arginina N-Metiltransferases/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/fisiologia , Humanos , Isoquinolinas/farmacologia , NF-kappa B/metabolismo , Prognóstico , Pirimidinas/farmacologia , Ribonucleoproteínas/metabolismo , Transdução de Sinais/efeitos dos fármacos
11.
Leukemia ; 32(4): 1003-1015, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29158557

RESUMO

Dendritic cells (DCs) have a key role in regulating tumor immunity, tumor cell growth and drug resistance. We hypothesized that multiple myeloma (MM) cells might recruit and reprogram DCs to a tumor-permissive phenotype by changes within their microRNA (miRNA) network. By analyzing six different miRNA-profiling data sets, miR-29b was identified as the only miRNA upregulated in normal mature DCs and significantly downregulated in tumor-associated DCs. This finding was validated in primary DCs co-cultured in vitro with MM cell lines and in primary bone marrow DCs from MM patients. In DCs co-cultured with MM cells, enforced expression of miR-29b counteracted pro-inflammatory pathways, including signal transducer and activator of transcription 3 and nuclear factor-κB, and cytokine/chemokine signaling networks, which correlated with patients' adverse prognosis and development of bone disease. Moreover, miR-29b downregulated interleukin-23 in vitro and in the SCID-synth-hu in vivo model, and antagonized a Th17 inflammatory response. All together, these effects translated into strong anti-proliferative activity and reduction of genomic instability of MM cells. Our study demonstrates that MM reprograms the DCs functional phenotype by downregulating miR-29b whose reconstitution impairs DCs ability to sustain MM cell growth and survival. These results underscore miR-29b as an innovative and attractive candidate for miRNA-based immune therapy of MM.


Assuntos
Células Dendríticas/patologia , Inflamação/genética , MicroRNAs/genética , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Animais , Medula Óssea/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação para Baixo/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Camundongos , Camundongos SCID , NF-kappa B/genética , Fator de Transcrição STAT3/genética , Regulação para Cima/genética
12.
Plant Physiol Biochem ; 110: 50-58, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27665987

RESUMO

Little is known about the interaction of nanoparticles (NPs) with soil constituents and their effects in plants. Boron (B), an essential micronutrient that reduces crop production at both deficiency and excess, has not been investigated with respect to its interaction with cerium oxide NPs (nano-CeO2). Considering conflicting results on the nano-CeO2 toxicity and protective role as antioxidant, their possible modulation on B toxicity in sunflower (Helianthus annuus L.) was investigated. Sunflower was cultivated for 30 days in garden pots containing original or B-spiked soil amended with nano-CeO2 at 0-800 mg kg-1. At harvest, Ce and B concentrations in tissues, biomass, and activities of stress enzymes in leaves were determined. Results showed that in the original soil, Ce accumulated mainly in roots, with little translocation to stems and leaves, while reduced root Ce was observed in plants from B-spiked soil. In the original soil, higher levels of nano-CeO2 reduced plant B concentration. Although morphological effects were not visible, changes in biomass and oxidative stress response were observed. Sunflower leaves from B-spiked soil showed visible symptoms of B toxicity, such as necrosis and chlorosis in old leaves, as well as an increase of superoxide dismutase (SOD) activity. However, at high nano-CeO2 level, SOD activity decreased reaching values similar to that of the control. This study has shown that nano-CeO2 reduced both the B nutritional status of sunflower in original soil and the B phytotoxicity in B-spiked soil.


Assuntos
Antioxidantes/química , Cério/química , Helianthus/efeitos dos fármacos , Nanopartículas/química , Fenômenos Fisiológicos Vegetais/efeitos dos fármacos , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Boro/química , Boro/metabolismo , Boro/toxicidade , Catalase/metabolismo , Helianthus/química , Helianthus/fisiologia , Nanopartículas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Folhas de Planta/química , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia , Proteínas de Plantas/metabolismo , Raízes de Plantas/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/fisiologia , Brotos de Planta/química , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/fisiologia , Solo/química , Poluentes do Solo/química , Poluentes do Solo/metabolismo , Poluentes do Solo/toxicidade , Superóxido Dismutase/metabolismo
13.
Leukemia ; 31(7): 1570-1581, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-27890927

RESUMO

Despite therapeutic advances, multiple myeloma (MM) remains an incurable disease, predominantly because of the development of drug resistance. The activator protein-1 (AP-1) transcription factor family has been implicated in a multitude of physiologic processes and tumorigenesis; however, its role in MM is largely unknown. Here we demonstrate specific and rapid induction of the AP-1 family member JunB in MM cells when co-cultured with bone marrow stromal cells. Supporting a functional key role of JunB in MM pathogenesis, knockdown of JUNB significantly inhibited in vitro MM cell proliferation and survival. Consistently, induced silencing of JUNB markedly decreased tumor growth in a murine MM model of the microenvironment. Subsequent gene expression profiling revealed a role for genes associated with apoptosis, DNA replication and metabolism in driving the JunB-mediated phenotype in MM cells. Importantly, knockdown of JUNB restored the response to dexamethasone in dexamethasone-resistant MM cells. Moreover, 4-hydroxytamoxifen-induced activation of a JunB-ER fusion protein protected dexamethasone-sensitive MM cells against dexamethasone- and bortezomib-induced cytotoxicity. In summary, our results demonstrate for the first time a specific role for AP-1/JunB in MM cell proliferation, survival and drug resistance, thereby strongly supporting that this transcription factor is a promising new therapeutic target in MM.


Assuntos
Medula Óssea/patologia , Mieloma Múltiplo/patologia , Fatores de Transcrição/fisiologia , Microambiente Tumoral , Animais , Bortezomib/farmacologia , Proliferação de Células , Dexametasona/farmacologia , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Camundongos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , NF-kappa B/fisiologia
14.
Braz J Biol ; 66(1A): 117-20, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16680314

RESUMO

Last instar larva and pupa of Paramallocera hirta Kirby, 1818 are described and illustrated based on specimens reared in the laboratory from neonate larvae on Eucalyptus globulus ssp. globulus logs and on an artificial diet. Characteristics of possible diagnostic value are also presented in this paper.


Assuntos
Besouros/anatomia & histologia , Animais , Besouros/crescimento & desenvolvimento , Eucalyptus/parasitologia , Larva/anatomia & histologia , Pupa/anatomia & histologia , Uruguai
15.
Diabetes ; 39(1): 76-82, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1698674

RESUMO

Differential solute clearances were used to examine the effects of a 90-day course of enalapril on glomerular barrier function in 16 proteinuric patients with diabetic glomerulopathy. By day 90, plasma renin and prorenin became elevated, and arterial pressure declined. Transglomerular passage of dextrans of broad size distribution (radii 28-60 A) was lowered significantly. In a subset of 8 patients, withdrawal of enalapril was followed after an additional 30 days by a return of renin levels and arterial pressure to pretreatment levels. The dextran-sieving profile also returned to baseline, becoming uniformly elevated above treated day-90 levels. A theoretical analysis of the serial dextran-sieving profiles indicated that enalapril shifted glomerular pore size distribution to smaller size. These changes in barrier size selectivity were associated with a reduction in fractional albumin and IgG clearances during enalapril therapy and a subsequent rise in these quantities after its withdrawal; urinary protein excretion rate tended to vary in parallel. We conclude that inhibition of converting enzyme in humans with established diabetic glomerulopathy diminishes glomerular permeability to proteins by enhancing barrier size selectivity. Because neither enalapril therapy nor its withdrawal influenced the glomerular filtration or renal plasma flow rates significantly, we propose that the primary action of enalapril may be to modulate the intrinsic membrane properties of the glomerular barrier.


Assuntos
Inibidores da Enzima Conversora de Angiotensina/farmacologia , Permeabilidade da Membrana Celular/fisiologia , Nefropatias Diabéticas/fisiopatologia , Glomérulos Renais/fisiopatologia , Oligopeptídeos/farmacologia , Adulto , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/fisiologia , Membrana Celular/ultraestrutura , Permeabilidade da Membrana Celular/efeitos dos fármacos , Dextranos/farmacocinética , Nefropatias Diabéticas/tratamento farmacológico , Enalapril/farmacologia , Enalapril/uso terapêutico , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Taxa de Filtração Glomerular/fisiologia , Humanos , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/ultraestrutura , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/uso terapêutico , Proteínas/farmacocinética , Teprotida
16.
Braz J Biol ; 65(1): 97-100, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16025908

RESUMO

Last instar larva and pupa of Eurymerus eburioides Audinet-Serville, 1833, are described and illustrated based on specimens reared from neonate larvae on Eucalyptus globulus globulus logs in the laboratory. Characters of possible diagnostic value are presented in this work.


Assuntos
Besouros/anatomia & histologia , Animais , Besouros/crescimento & desenvolvimento , Feminino , Larva/anatomia & histologia , Masculino , Pupa/anatomia & histologia
17.
Leukemia ; 29(11): 2173-83, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25987254

RESUMO

Interferon regulatory factor 4 (IRF4) is an attractive therapeutic target in multiple myeloma (MM). We here report that expression of IRF4 mRNA inversely correlates with microRNA (miR)-125b in MM patients. Moreover, we provide evidence that miR-125b is downregulated in TC2/3 molecular MM subgroups and in established cell lines. Importantly, constitutive expression of miR-125b-5p by lentiviral vectors or transfection with synthetic mimics impaired growth and survival of MM cells and overcame the protective role of bone marrow stromal cells in vitro. Apoptotic and autophagy-associated cell death were triggered in MM cells on miR-125b-5p ectopic expression. Importantly, we found that the anti-MM activity of miR-125b-5p was mediated via direct downregulation of IRF4 and its downstream effector BLIMP-1. Moreover, inhibition of IRF4 translated into downregulation of c-Myc, caspase-10 and cFlip, relevant IRF4-downstream effectors. Finally, in vivo intra-tumor or systemic delivery of formulated miR-125b-5p mimics against human MM xenografts in severe combined immunodeficient/non-obese diabetic mice induced significant anti-tumor activity and prolonged survival. Taken together, our findings provide evidence that miR-125b, differently from other hematologic malignancies, has tumor-suppressor activity in MM. Furthermore, our data provide proof-of-concept that synthetic miR-125b-5p mimics are promising anti-MM agents to be validated in early clinical trials.


Assuntos
Fatores Reguladores de Interferon/genética , MicroRNAs/fisiologia , Mieloma Múltiplo/terapia , Animais , Apoptose , Autofagia , Linhagem Celular Tumoral , Proliferação de Células , Genes Supressores de Tumor/fisiologia , Humanos , Masculino , Camundongos , Mieloma Múltiplo/patologia
18.
J Med Chem ; 42(21): 4362-79, 1999 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-10543880

RESUMO

The synthesis, pharmacological evaluation, and structure-activity relationships (SARs) of a series of novel pyrroloquinoxalines and heteroaromatic-related derivatives are described. The new pyrroloquinoxaline-related ligands were tested in rat cortex, a tissue expressing high density of 5-HT(3) receptors, and on NG108-15 cells and exhibited IC(50) values in the low nanomolar or subnanomolar range, as measured by the inhibition of [(3)H]zacopride binding. The SAR studies detailed herein delineated a number of structural features required for improving affinity. Some of the ligands were employed as "molecular yardsticks" to probe the spatial dimensions of the lipophilic pockets L1, L2, and L3 in the 5-HT(3) receptor cleft, while the 7-OH pyrroloquinoxaline analogue was designed to investigate hydrogen bonding with a putative receptor site H1 possibly interacting with the serotonin hydroxy group. The most active pyrroloquinoxaline derivatives showed subnanomolar affinity for the 5-HT(3) receptor. In functional studies ([(14)C]guanidinium accumulation test in NG108-15 hybrid cells, in vitro) most of the tested compounds showed clear-cut 5-HT(3) agonist properties, while some others were found to be partial agonists. Several heteroaromatic systems, bearing N-substituted piperazine moieties, have been explored with respect to 5-HT(3) affinity, and novel structural leads for the development of potent and selective central 5-HT(3) receptor agonists have been identified. Preliminary pharmacokinetic studies indicate that these compounds easily cross the blood-brain barrier (BBB) after systemic administration with a brain/plasma ratio between 2 and 20, unless they bear a highly hydrophilic group on the piperazine ring. None of the tested compounds showed in vivo anxiolytic-like activity, but potential analgesic-like properties have been possibly disclosed for this new class of 5-HT(3) receptor agonists.


Assuntos
Pirróis/síntese química , Quinoxalinas/síntese química , Receptores de Serotonina/efeitos dos fármacos , Agonistas do Receptor de Serotonina/síntese química , Animais , Ansiolíticos/síntese química , Ansiolíticos/química , Ansiolíticos/farmacocinética , Ansiolíticos/farmacologia , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Anti-Inflamatórios não Esteroides/farmacologia , Barreira Hematoencefálica , Encéfalo/metabolismo , Guanidina/metabolismo , Cobaias , Células Híbridas , Técnicas In Vitro , Ligantes , Masculino , Pirróis/química , Pirróis/farmacocinética , Pirróis/farmacologia , Quinoxalinas/química , Quinoxalinas/farmacocinética , Quinoxalinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores 5-HT3 de Serotonina , Antagonistas da Serotonina/síntese química , Antagonistas da Serotonina/química , Antagonistas da Serotonina/farmacocinética , Antagonistas da Serotonina/farmacologia , Agonistas do Receptor de Serotonina/química , Agonistas do Receptor de Serotonina/farmacocinética , Agonistas do Receptor de Serotonina/farmacologia , Relação Estrutura-Atividade
19.
J Med Chem ; 42(21): 4462-70, 1999 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-10543890

RESUMO

Pyrrolobenzoxazepinone (PBO) derivatives represent a new class of human immunodeficiency virus type 1 (HIV-1) non-nucleoside reverse transcriptase (RT) inhibitors (NNRTs) whose prototype is (+/-)-6-ethyl-6-phenylpyrrolo[2,1-d][1,5]benzoxazepin-7(6H)- one (6). Docking studies based on the three-dimensional structure of RT prompted the synthesis and biological evaluation of novel derivatives and analogues of 6 featuring a meta-substituted phenyl or a 2-thienyl ring at C-6 and a pyridine system in place of the fused-benzene ring to yield pyrrolopyridooxazepinones (PPOs). Compared with the lead 6 and nevirapine, several of the synthesized compounds (PBOs 13a-d and PPOs 13i-k) displayed higher inhibitory activity against wild-type RT and clinically relevant mutant RTs containing the single amino acid substitutions L100I, K103N, V106A, Y181I, and Y188L. The most potent inhibitors were further evaluated for in vitro antiviral activity on lymphocytes and monocyte-macrophages, for cytotoxicity on a panel of cell lines, and for potential synergistic antiviral activity with AZT. Pharmacokinetic studies performed on 13b, 13c, and 13i showed that these compounds achieve high concentrations in the brain. The results of the biological and pharmacokinetic experiments suggest a potential clinical utility of analogues such as 13b-d, 13i, and 13j, in combination with nucleoside RT inhibitors, against strains of HIV-1 bearing those mutations that confer resistance to known NNRTI.


Assuntos
Fármacos Anti-HIV/síntese química , Azepinas/síntese química , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Inibidores da Transcriptase Reversa/síntese química , Animais , Fármacos Anti-HIV/química , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/toxicidade , Azepinas/química , Azepinas/farmacologia , Azepinas/toxicidade , Linhagem Celular , Desenho de Fármacos , Sinergismo Farmacológico , Imunofluorescência , Humanos , Camundongos , Modelos Moleculares , Inibidores da Transcriptase Reversa/química , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/toxicidade , Relação Estrutura-Atividade , Zidovudina/farmacologia
20.
J Med Chem ; 44(26): 4501-4, 2001 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11741469

RESUMO

(S)-CPW399 (2b) is a novel, potent, and subtype-selective AMPA receptor full agonist that, unlike (S)-willardiine and related compounds, in mouse cerebellar granule cells, stimulated an increase in [Ca(2+)](i), and induced neuronal cell death in a time- and concentration-dependent manner. Compound 2b appears to be a weakly desensitizing, full agonist at AMPA receptors and therefore represents a new pharmacological tool to investigate the role of AMPA receptors in excitotoxicity and their molecular mechanisms of desensitization.


Assuntos
Alanina/síntese química , Agonistas de Aminoácidos Excitatórios/síntese química , Pirimidinas/síntese química , Pirimidinonas/síntese química , Receptores de AMPA/agonistas , Alanina/análogos & derivados , Alanina/farmacologia , Animais , Encéfalo/citologia , Encéfalo/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular , Eletrofisiologia , Agonistas de Aminoácidos Excitatórios/farmacologia , Técnicas In Vitro , Ligantes , Camundongos , Modelos Moleculares , Neurônios/citologia , Neurônios/efeitos dos fármacos , Oócitos/metabolismo , Pirimidinas/farmacologia , Pirimidinonas/farmacologia , Ensaio Radioligante , Ratos , Receptores de AMPA/metabolismo , Receptores de AMPA/fisiologia , Proteínas Recombinantes/metabolismo , Estereoisomerismo , Xenopus laevis
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