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1.
Front Vet Sci ; 10: 1286158, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38094499

RESUMO

Introduction: Cannabinoids are increasingly popular in human and veterinary medicine and have been studied as an alternative treatment for a wide range of disorders. The goal of this study was to perform a pharmacokinetic analysis of oral cannabidiol (CBD)-/cannabidiolic acid (CBDA)-rich hemp oil (CBD/ArHO) in juvenile cynomolgus macaques (Macaca fascicularis). Methods: After a 2 mg/kg CBD/ArHO pilot study, 4 and 8 mg/kg direct-to-mouth CBD/ArHO were administered (n = 4 per dose) once daily for 14 days and blood was collected at 0-, 0.5-, 1-, 2-, 4-, 8-, 12-, and 24-h, and on Days 7 and 14, to quantify serum cannabinoid concentrations by high-performance liquid chromatography-tandem mass spectrometry. Serum biochemistries and complete blood counts were performed on Days 0, 1, and 14. Results: The maximum mean serum concentration (Cmax) of CBDA was 28.6-36.2 times that of CBD at 4 and 8 mg/kg. At 8 mg/kg, the Cmax of CBD was 1.4 times higher (p = 0.0721), and CBDA was significantly 1.8 times higher (p = 0.0361), than at 4 mg/kg. The maximum mean serum concentration of ∆9-tetrahydrocannabinol (THC) was 4.80 ng/mL at 8 mg/kg. Changes in serum biochemistries and complete blood counts over time were not clinically significant. Discussion: Given the low serum CBD concentrations, the doses and frequency used in this study may be insufficient for a therapeutic effect of CBD in particular; therefore, clinical studies are needed to determine the therapeutic dose of CBD and CBDA for macaques, which may differ based on the disorder targeted.

2.
Front Immunol ; 13: 1010605, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36451826

RESUMO

Multiple sclerosis (MS) is a heterogeneous disease where herpesvirus infection and genetic predisposition are identified as the most consistent risk factors. Serum and blood samples were collected from 151 MS and 70 controls and used to analyze circulating antibodies for, and DNA of, Epstein Barr virus (EBV), human cytomegalovirus (HCMV), human herpes virus 6 (HHV6), and varicella zoster virus (VZV). The frequency of selected single nucleotide polymorphisms (SNPs) in MS and controls were studied. Herpesvirus DNA in blood samples were analyzed using qPCR. Anti-herpesvirus antibodies were detected by ELISA. SNPs were analyzed by the allele-specific PCR. For statistical analysis, Fisher exact test, odds ratio and Kruskall-Wallis test were used; p<0.05 values were considered as significant. We have found an association between circulating anti-HHV6 antibodies and MS diagnosis. We also confirmed higher frequency of A and C alleles in rs2300747 and rs12044852 of CD58 gene and G allele in rs929230 of CD6 gene in MS as compared to controls. Fatigue symptom was linked to AC and AA genotype in rs12044852 of CD58 gene. An interesting observation was finding higher frequency of GG genotype in rs12722489 of IL2RA and T allele in rs1535045 of CD40 genes in patient having anti-HHV6 antibodies. A link was found between having anti-VZV antibodies in MS and CC genotype in rs1883832 of CD40 gene.


Assuntos
Infecções por Vírus Epstein-Barr , Herpesvirus Humano 6 , Esclerose Múltipla , Humanos , Polimorfismo de Nucleotídeo Único , Esclerose Múltipla/genética , Infecções por Vírus Epstein-Barr/epidemiologia , Infecções por Vírus Epstein-Barr/genética , Herpesvirus Humano 4/genética , Fatores de Risco , Federação Russa/epidemiologia , Anticorpos Antivirais
3.
Sci Transl Med ; 12(552)2020 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-32669423

RESUMO

Inefficient delivery is a major obstacle to the development of peptide-based drugs targeting the intracellular compartment. We recently showed that selectively inhibiting integrin outside-in signaling using a peptide (mP6) derived from the Gα13-binding ExE motif within the integrin ß3 cytoplasmic domain had antithrombotic effects. Here, we engineered lipid-stabilized, high-loading peptide nanoparticles (HLPN), in which a redesigned ExE peptide (M3mP6) constituted up to 70% of the total nanoparticle molarity, allowing efficient in vivo delivery. We observed that M3mP6 HLPN inhibited occlusive thrombosis more potently than a clopidogrel/aspirin combination without adverse effects on hemostasis in rodents. Furthermore, M3mP6 HLPN synergized with P2Y12 receptor inhibitors or the clopidogrel/aspirin combination in preventing thrombosis, without exacerbating hemorrhage. M3mP6 HLPN also inhibited intravascular coagulation more potently than the P2Y12 inhibitor cangrelor. Postischemia injection of M3mP6 HLPN protected the heart from myocardial ischemia-reperfusion injury in a mouse model. This study demonstrates an efficient in vivo peptide delivery strategy for a therapeutic that not only efficaciously prevented thrombosis with minimal bleeding risk but also protected from myocardial ischemia-reperfusion injury in mice.


Assuntos
Traumatismo por Reperfusão Miocárdica , Nanopartículas , Preparações Farmacêuticas , Trombose , Animais , Isquemia , Camundongos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Peptídeos , Trombose/prevenção & controle
4.
PLoS One ; 12(2): e0171703, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28207794

RESUMO

We evaluated the mitigating effects of fibroblast growth factor 4 and 7 (FGF4 and FGF7, respectively) in comparison with long acting protected graft copolymer (PGC)-formulated FGF4 and 7 (PF4 and PF7, respectively) administered to C57BL/6J mice a day after exposure to LD50/30 (15.7 Gy) partial body irradiation (PBI) which targeted the gastrointestinal (GI) system. The PGC that we developed increased the bioavailability of FGF4 and FGF7 by 5- and 250-fold compared to without PGC, respectively, and also sustained a 24 hr presence in the blood after a single subcutaneous administration. The dose levels tested for mitigating effects on radiation injury were 3 mg/kg for the PF4 and PF7 and 1.5 mg each for their combination (PF4/7). Amifostine administered prior to PBI was used as a positive control. The PF4, PF7, or PF4/7 mitigated the radiation lethality in mice. The mitigating effect of PF4 and PF7 was similar to the positive control and PF7 was better than other mitigators tested. The plasma citrulline levels and hematology parameters were early markers of recovery and survival. GI permeability function appeared to be a late or full recovery indicator. The villus length and crypt number correlated with plasma citrulline level, indicating that it can act as a surrogate marker for these histology evaluations. The IL-18 concentrations in jejunum as early as day 4 and TPO levels in colon on day 10 following PBI showed statistically significant changes in irradiated versus non-irradiated mice which makes them potential biomarkers of radiation exposure. Other colon and jejunum cytokine levels are potentially useful but require larger numbers of samples than in the present study before their full utility can be realized.


Assuntos
Síndrome Aguda da Radiação/tratamento farmacológico , Fatores de Crescimento de Fibroblastos/uso terapêutico , Trato Gastrointestinal/efeitos dos fármacos , Lesões Experimentais por Radiação/terapia , Animais , Proliferação de Células/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Feminino , Fator 4 de Crescimento de Fibroblastos/efeitos adversos , Fator 4 de Crescimento de Fibroblastos/uso terapêutico , Fator 7 de Crescimento de Fibroblastos/efeitos adversos , Fator 7 de Crescimento de Fibroblastos/uso terapêutico , Fatores de Crescimento de Fibroblastos/efeitos adversos , Fibroblastos/efeitos dos fármacos , Trato Gastrointestinal/patologia , Trato Gastrointestinal/efeitos da radiação , Estimativa de Kaplan-Meier , Dose Letal Mediana , Masculino , Camundongos Endogâmicos C57BL , Polilisina/química , Polímeros/química
5.
Int J Cancer ; 140(3): 726-735, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27770551

RESUMO

Neuroblastoma is the most common extracranial childhood solid tumor. Treatment of high risk tumors require intense multicycle chemotherapies, resulting in short- and long-term toxicities. Here, we present treatment of an orthotopic neuroblastoma mouse model, with silk fibroin materials loaded with vincristine, doxorubicin or the combination as a intratumoral, sustained release system. The materials, loaded with vincristine with or without doxorubicin, significantly decreased neuroblastoma tumor growth compared to materials loaded without drug or doxorubicin only as well as intravenous (IV) drug treatment. The intratumoral drug concentration was significantly higher with intratumoral delivery versus IV. Furthermore, intratumor delivery decreased the maximum plasma concentration compared to IV delivery, reducing systemic exposure and possibly reduing long-term side effects of chemotherapy exposure. Histopathologically, tumors with remission periods >25 days before recurrence transformed from a "small-round-blue cell" (SBRC) to predominantly "large cell" neuroblastoma (LCN) histopathology, a more aggressive tumor subtype with unfavorable clinical outcomes. These results show that intratumoral chemotherapy delivery may be a treatment strategy for pediatric neuroblastoma, potentially translatable to other focal tumors types. Furthermore, this treatment modality allows for a clinically relevant mouse model of tumor transformation that may be used for studying the phenotypical tumor recurrence and developing more effective treatment strategies for recurrent tumors.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Fibroínas/administração & dosagem , Neuroblastoma/tratamento farmacológico , Seda/administração & dosagem , Vincristina/administração & dosagem , Animais , Linhagem Celular Tumoral , Preparações de Ação Retardada/administração & dosagem , Modelos Animais de Doenças , Sistemas de Liberação de Medicamentos/métodos , Camundongos , Recidiva Local de Neoplasia/tratamento farmacológico
6.
Arterioscler Thromb Vasc Biol ; 33(11): 2529-37, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24051142

RESUMO

OBJECTIVE: Poor prognosis of sepsis is associated with bacterial lipopolysaccharide (LPS)-induced intravascular inflammation, microvascular thrombosis, thrombocytopenia, and disseminated intravascular coagulation. Platelets are critical for thrombosis, and there has been increasing evidence of the importance of platelets in endotoxemia. The platelet adhesion receptor, the glycoprotein Ib-IX complex (GPIb-IX), mediates platelet adhesion to inflammatory vascular endothelium and exposed subendothelium. Thus, we have investigated the role of GPIb-IX in LPS-induced platelet adhesion, thrombosis, and thrombocytopenia. APPROACH AND RESULTS: LPS-induced mortality is significantly decreased in mice expressing a functionally deficient mutant of GPIbα. Furthermore, we have developed a micellar peptide inhibitor, MPαC (C13H27CONH-SIRYSGHpSL), which selectively inhibits the von Willebrand factor -binding function of GPIb-IX and GPIb-IX-mediated platelet adhesion under flow without affecting GPIb-IX-independent platelet activation. MPαC inhibits platelet adhesion to LPS-stimulated endothelial cells in vitro and alleviates LPS-induced thrombosis in glomeruli in mice. Importantly, MPαC reduces mortality in LPS-challenged mice, suggesting a protective effect of this inhibitor during endotoxemia. Interestingly, MPαC, but not the integrin antagonist, Integrilin, alleviated LPS-induced thrombocytopenia. CONCLUSIONS: These data indicate an important role for the platelet adhesion receptor GPIb-IX in LPS-induced thrombosis and thrombocytopenia, and suggest the potential of targeting GPIb as an antiplatelet strategy in managing endotoxemia.


Assuntos
Endotoxemia/metabolismo , Glicoproteínas de Membrana/metabolismo , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo , Trombocitopenia/metabolismo , Trombose/metabolismo , Animais , Endotélio Vascular/metabolismo , Endotoxemia/tratamento farmacológico , Endotoxemia/mortalidade , Humanos , Lipopolissacarídeos/farmacologia , Glicoproteínas de Membrana/antagonistas & inibidores , Glicoproteínas de Membrana/genética , Camundongos , Camundongos Transgênicos , Peptídeos/farmacologia , Adesividade Plaquetária/efeitos dos fármacos , Adesividade Plaquetária/fisiologia , Inibidores da Agregação Plaquetária/farmacologia , Complexo Glicoproteico GPIb-IX de Plaquetas/antagonistas & inibidores , Complexo Glicoproteico GPIb-IX de Plaquetas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Trombocitopenia/tratamento farmacológico , Trombocitopenia/mortalidade , Trombose/tratamento farmacológico , Trombose/mortalidade , Fator de von Willebrand/metabolismo
7.
Drug Chem Toxicol ; 36(3): 284-95, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22947079

RESUMO

SHetA2 is a heteroarotinoid that has shown selective inhibition of cancer cell growth and an induction of apoptosis without activation of nuclear retinoic acid receptors. In the rat study, SHetA2 was administered in 1% aqueous methylcellulose/0.2% Tween 80 by oral gavage at 0, 100, 500, and 2,000 mg/kg/day for 28 days. The high-dose administration induced decreased activity in male rats, decreased body-weight gains and food consumption, and changes in organ weights. The major metabolite of SHetA2 in rat plasma was monohydroxy SHetA2, which was considerably higher than the parent compound after oral and intravenous administration. Pharmacokinetic analysis showed extremely low (<1%) systemic bioavailability of SHetA2 for all doses tested. The dose of 2,000 mg/kg/day was considered as the lowest observed adverse effect level. The no observed adverse effect level (NOAEL) was 500 mg/kg/day. In the dog study, no toxicity of SHetA2 in 30% aqueous Solutol(®) HS 15 was observed in any tested dose groups (0, 100, 400, and 1,500 mg/kg/day). The major metabolite of SHetA2 in dog plasma was also monohydroxy SHetA2, which was equal to or lower than the parent compound after oral administration. SHetA2 levels in dog plasma were notably higher, when compared to levels in rat plasma. However, exposure was not dose proportional, as exemplified by a lack of proportional increase in maximum concentration or area under the plasma concentration-time curve with increasing dose. The NOAEL was not established and was considered to be above 1,500 mg/kg/day.


Assuntos
Anticarcinógenos/farmacocinética , Anticarcinógenos/toxicidade , Cromanos/farmacocinética , Cromanos/toxicidade , Tionas/farmacocinética , Tionas/toxicidade , Administração Oral , Glândulas Suprarrenais/efeitos dos fármacos , Glândulas Suprarrenais/patologia , Animais , Anticarcinógenos/administração & dosagem , Área Sob a Curva , Cromanos/administração & dosagem , Cães , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Masculino , Atividade Motora/efeitos dos fármacos , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Próstata/efeitos dos fármacos , Próstata/patologia , Ratos , Ratos Sprague-Dawley , Especificidade da Espécie , Tionas/administração & dosagem , Testes de Toxicidade , Aumento de Peso/efeitos dos fármacos
8.
Dalton Trans ; 39(30): 6960-6, 2010 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-20440427

RESUMO

The equilibrium molecular structure of octaphenyloctasilsesquioxane Si(8)O(12)Ph(8) in the gas phase has been determined by electron diffraction. It was found to have D(4) point-group symmetry, with Si-O bond lengths of 1.634(15)-1.645(19) A, and a narrow range [147.5(45)-149.8(24) degrees] of Si-O-Si angles. The structures of Si(8)O(12)(p-tolyl)(8) and Si(8)O(12)(p-ClCH(2)C(6)H(4))(8) have been determined by X-ray diffraction and are found to have Si(8)O(12) cages significantly distorted from the symmetry found for Si(8)O(12)Ph(8) in the gas phase. Thus, Si-O-Si angles range between 144.2(2)-151.64(16) degrees for Si(8)O(12)(p-tolyl)(8), and between 138.8(2)-164.2(2) degrees for Si(8)O(12)(p-ClCH(2)C(6)H(4))(8). These three structures show how much a Si(8)O(12) cage may be distorted away from an ideal structure, free from intermolecular forces, by packing forces in a crystalline lattice.


Assuntos
Compostos de Organossilício/química , Cristalografia por Raios X , Gases/química , Modelos Moleculares , Estrutura Molecular , Compostos de Organossilício/síntese química
9.
Toxicology ; 273(1-3): 19-28, 2010 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-20430063

RESUMO

2,2,5,7,8-Pentamethyl-6-chromanol (PMCol) was administered by gavage in rats for 28 days at dose levels of 0, 100, 500, and 2000mg/kg/day. PMCol administration induced decreases in body weight gains and food consumption, hepatotoxicity (increased TBILI, ALB, ALT, TP; increased relative liver weights; increased T4 and TSH), nephrotoxicity (increased BUN and BUN/CREAT, histopathology lesions), effect on lipid metabolism (increased CHOL), anemia, increase in WBC counts (total and differential), coagulation (FBGN upward arrow and PT downward arrow) and hyperkeratosis of the nonglandular stomach in the 2000mg/kg/day dose group (in one or both sexes). In the 500mg/kg/day dose group, toxicity was seen to a lesser extent. In the 100mg/kg/day dose group, only increased CHOL (females) was observed. To assess the toxicity of PMCol in male dogs it was administered orally by capsule administration for 28 days at dose levels of 0, 50, 200 and 800mg/kg/day (four male dogs/dose group). PMCol treatment at 800mg/kg/day resulted in pronounced toxicity to the male dogs. Target organs of toxicity were liver and thymus. Treatment at 200mg/kg/day resulted in toxicity consistent with slight adverse effect on the liver only. The results of the safety pharmacology study indicate that doses of 0, 50, 200 and 800mg/kg administered orally did not have an effect on the QT interval, blood pressures and body temperatures following dosing over a 24-h recording period. Under the conditions of this study, the no-observed-adverse effect level (NOAEL) for daily oral administration of PMCol by gavage for 28 days to male rats was 100mg/kg/day and 50mg/kg in male dogs. In female rats, the NOAEL was not established due to statistically significant and biologically meaningful increases in CHOL level seen in the 100mg/kg/day dose group. The results of these studies indicated that administration of PMCol at higher dose levels resulted in severe toxicity in dogs and moderate toxicity in rats, however, administration at lower levels is considered to be less likely to result in toxicity following 28 days of exposure. Sex-related differences were seen in rats. Male rats appeared to have greater sensitivity to nephrotoxicity, while female animals had a greater incidence of hepatoxicity and changes in hematological parameters evaluated, especially at a dose of 500mg/kg/day, which correlated to the higher plasma drug levels in female rats. It appeared that dogs were generally more sensitive than rats to oral administration of PMCol. Further examination of the potential toxic effects of PMCol in longer term studies is required prior to understanding the full risks of PMCol administration as a chemopreventative agent.


Assuntos
Anticarcinógenos/toxicidade , Cromanos/toxicidade , Administração Oral , Animais , Anticarcinógenos/administração & dosagem , Cromanos/administração & dosagem , Cães , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Masculino , Tamanho do Órgão/efeitos dos fármacos , Ratos , Testes de Toxicidade
10.
Phys Chem Chem Phys ; 11(38): 8570-9, 2009 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-19774289

RESUMO

The gas-phase molecular structure of a thiadiazole-containing expanded heteroazaporphyrinoid (C42H39N15S3) has been studied by a synchronous gas electron diffraction and mass spectrometric experiment and density functional theory calculations using the B3LYP hybrid method and cc-pVTZ basis sets. The molecule has an equilibrium structure of C3h symmetry with a planar macrocycle and the thiadiazole rings oriented in such a way that the sulfur atoms point outwards from the inner cavity. The unsubstituted macrocycle (C30H15N15S3) has been studied by DFT computations. An algorithm for building a complete set of internal coordinates, used in the computation of vibrational corrections, is also described.


Assuntos
Simulação por Computador , Elétrons , Gases/química , Modelos Químicos , Porfirinas/química , Teoria Quântica , Tiadiazóis/química , Espectrometria de Massas , Modelos Moleculares
11.
J Phys Chem A ; 113(34): 9511-20, 2009 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-19645487

RESUMO

A general method is described that allows experimental equilibrium structures to be determined from gas electron diffraction (GED) data. Distance corrections, starting values for amplitudes of vibration and anharmonic "Morse" constants (all required for a GED refinement) have been extracted from molecular dynamics (MD) simulations. For this purpose MD methods have significant advantages over traditional force-field methods, as they can more easily be performed for large molecules, and, as they do not rely on extrapolation from equilibrium geometries, they are highly suitable for molecules with large-amplitude and anharmonic modes of vibration. For the test case Si(8)O(12)Me(8), where the methyl groups rotate and large deformations of the Si(8)O(12) cage are observed, the MD simulations produced results markedly superior to those obtained using force-field methods. The experimental equilibrium structure of Si(8)O(12)H(8) has also been determined, demonstrating the use of empirical potentials rather than DFT methods when such potentials exist. We highlight the one major deficiency associated with classical MD--the absence of quantum effects--which causes some light-atom bonded-pair amplitudes of vibration to be significantly underestimated. However, using C(3)N(3)Cl(3) and C(3)N(3)H(3) as examples, we show that path-integral MD simulations can overcome these problems. The distance corrections and amplitudes of vibration obtained for C(3)N(3)Cl(3) are almost identical to those obtained from force-field methods, as we would expect for such a rigid molecule. In the case of C(3)N(3)H(3), for which an accurate experimental structure exists, the use of path-integral methods more than doubles the C-H amplitude of vibration.

12.
Phys Chem Chem Phys ; 11(18): 3472-7, 2009 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-19421550

RESUMO

The gas-phase molecular structure of oxotitanium phthalocyanine (TiOPc) has been studied by a synchronous gas electron diffraction and mass spectrometric experiment, and density functional theory calculations using the B3LYP hybrid method and cc-pVTZ basis sets. The molecule has an equilibrium structure of C4v symmetry with a convex macrocycle. The titanium atom is out-of-the-plane of the four central nitrogen atoms and forms a square pyramid with them, with the following parameters: r(Ti-N)=2.090(5) A, r(NN)=2.813(9) A (the side of the pyramid base), z(Ti)-z(N)=0.614 A (the height of the pyramid). Compared to solid-state crystal structures, the Ti-O distance in gas-phase TiOPc is shortened and the Ti-N distance is elongated, which can be attributed to significant intermolecular interaction in the crystals.

13.
Chem Biol Interact ; 179(2-3): 233-9, 2009 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-18992230

RESUMO

Aspirin is one of the oldest drugs and has been purported to have multiple beneficial effects, including prevention of cardiovascular disease and cancer, in addition to its original indication for treatment of inflammation, fever and pain. In cancer chemoprevention studies using animal models, two methods of aspirin administration have been employed: oral gavage and diet. The untested assumption was that exposure and the resultant pharmacological effects are similar for these two administration methods when dosing is normalized on the basis of mg/kg body weight/day. This study examined and compared time-dependent plasma and colon mucosal concentrations of aspirin metabolite salicylate (aspirin concentrations were below level of quantification), plasma thromboxane B(2) concentrations, and colon mucosal prostaglandin E(2) concentration following these two different dosing paradigms in rats. Diet dosing yielded relatively constant plasma and colon salicylate concentration vs. time profiles. On the other hand, oral gavage dosing led to a rapid peak followed by a fast decline in salicylate concentration in both plasma and colon. Nevertheless, the exposure as measured by the area under plasma or colon concentration-time curve of salicylate was linearly related to dose irrespective of the dosing method. Linear relationships were also observed between colon and plasma salicylate areas under the curve and between colon prostaglandin E(2) and plasma thromboxane B(2) areas under the curve. Therefore, more easily accessible plasma salicylate and thromboxane B(2) concentrations were representative of the salicylate exposure and prostaglandin E(2) pharmacodynamic biomarker in the target colon, respectively.


Assuntos
Aspirina/administração & dosagem , Aspirina/farmacocinética , Dieta , Administração Oral , Animais , Aspirina/metabolismo , Colo/química , Colo/metabolismo , Dinoprostona/análise , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Endogâmicos F344 , Salicilatos/análise , Tromboxano B2/sangue , Fatores de Tempo
14.
Chem Commun (Camb) ; (30): 3573-5, 2008 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-18654717

RESUMO

The molecular structure of a macrocycle with a 24-membered ring, a thiadiazole-containing expanded heteroazaporphyrinoid, has been, for the first time, directly characterised by a synchronous gas electron diffraction and mass spectrometric experiment and DFT calculations; the molecule has the equilibrium structure of C(3h) symmetry with a planar macrocycle.

15.
Cancer Res ; 65(17): 7603-11, 2005 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16140925

RESUMO

AML1/MDS1/EVI1 (AME) is a chimeric transcription factor produced by the (3;21)(q26;q22) translocation. This chromosomal translocation is associated with de novo and therapy-related acute myeloid leukemia and with the blast crisis of chronic myelogenous leukemia. AME is obtained by in-frame fusion of the AML1 and MDS1/EVI1 (ME) genes. The mechanisms by which AME induces a neoplastic transformation in bone marrow cells are unknown. AME interacts with the corepressors CtBP and HDAC1, and it was shown that AME is a repressor in contrast to the parent transcription factors AML1 and ME, which are transcription activators. Studies with murine bone marrow progenitors indicated that the introduction of a point mutation that destroys the CtBP-binding consensus impairs but does not abolish the disruption of cell differentiation and replication associated with AME expression, suggesting that additional events are required. Several chimeric proteins, such as AML1/ETO, BCR/ABL, and PML/RARa, are characterized by the presence of a self-interaction domain critical for transformation. We report that AME is also able to oligomerize and displays a complex pattern of self-interaction that involves at least three oligomerization regions, one of which is the distal zinc finger domain. Although the deletion of this short domain does not preclude the self-interaction of AME, it significantly reduces the differentiation defects caused in vitro by AME in primary murine bone marrow progenitors. The addition of a point mutation that inhibits CtBP binding completely abrogates the effects of AME on differentiation, suggesting that AME induces hematopoietic differentiation defects through at least two separate but cooperating pathways.


Assuntos
Células-Tronco Hematopoéticas/citologia , Proteínas de Fusão Oncogênica/metabolismo , Proteínas Repressoras/metabolismo , Dedos de Zinco/fisiologia , Oxirredutases do Álcool , Animais , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Diferenciação Celular/fisiologia , Transformação Celular Neoplásica/metabolismo , Subunidade alfa 2 de Fator de Ligação ao Core , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Humanos , Camundongos , Células NIH 3T3 , Proteínas de Fusão Oncogênica/genética , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , Estrutura Terciária de Proteína , Proteínas Repressoras/genética , Transfecção , Regulação para Cima , Dedos de Zinco/genética
16.
J Exp Bot ; 55(402): 1463-71, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15181101

RESUMO

The organ specificity of four promoters that are known to direct seed-specific gene expression was tested. Whereas the phaseolin (phas)- and legumin B4 (leB4)-promoters were from genes encoding 7S and 11S globulins from Phaseolus vulgaris and Vicia faba, respectively, the usp- and the sbp-promoters were from non-storage protein genes of V. faba. The expression of different promoter-reporter gene fusions was followed either by RT-PCR or by registering the reporter enzyme activity in organs of transgenic tobacco, pea, narbon bean, or linseed. In addition to seeds, the promoters directed reporter gene expression in pollen and in seed coats. USP-, vicilin- and legumin-mRNA were detected by RT-PCR in pollen of Pisum sativum and V. faba. Expression during microsporogenesis and embryogenesis seems to be a general character of various seed protein genes.


Assuntos
Regulação da Expressão Gênica de Plantas/genética , Regiões Promotoras Genéticas/genética , Sementes/genética , Pisum sativum/genética , Proteínas de Plantas/genética , Estruturas Vegetais/genética , Plantas Geneticamente Modificadas , Pólen/genética , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , alfa-Amilases/genética , Leguminas
17.
J Exp Bot ; 55(402): 1593-5, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15208344

RESUMO

Detailed analysis of the expression pattern of seven legumain genes from Nicotiana tabacum L. cv. SNN revealed that it showed neither coincidences with the branches of the phylogenetic tree of legumains nor with their conventional assignment to organs. This agreed well with the fact that, so far, no functional differences could be assigned to the sequence differences reflected in the branches of the tree.


Assuntos
Cisteína Endopeptidases/genética , Flores/genética , Regulação da Expressão Gênica de Plantas/genética , Nicotiana/genética , Sementes/genética , Flores/enzimologia , Regulação Enzimológica da Expressão Gênica/genética , Sementes/enzimologia
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