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1.
J Am Chem Soc ; 144(41): 18938-18947, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36197299

RESUMO

The fish oil constituent docosahexaenoic acid (DHA, 22:6 n-3) is a signaling lipid with anti-inflammatory properties. The molecular mechanisms underlying the biological effect of DHA are poorly understood. Here, we report the design, synthesis, and application of a complementary pair of bio-orthogonal, photoreactive probes based on the polyunsaturated scaffold DHA and its oxidative metabolite 17-hydroxydocosahexaenoic acid (17-HDHA). In these probes, an alkyne serves as a handle to introduce a fluorescent reporter group or a biotin-affinity tag via copper(I)-catalyzed azide-alkyne cycloaddition. This pair of chemical probes was used to map specific targets of the omega-3 signaling lipids in primary human macrophages. Prostaglandin reductase 1 (PTGR1) was identified as an interaction partner that metabolizes 17-oxo-DHA, an oxidative metabolite of 17-HDHA. 17-oxo-DHA reduced the formation of pro-inflammatory lipids 5-HETE and LTB4 in human macrophages and neutrophils. Our results demonstrate the potential of comparative photoaffinity protein profiling for the discovery of metabolic enzymes of bioactive lipids and highlight the power of chemical proteomics to uncover new biological insights.


Assuntos
Ácidos Docosa-Hexaenoicos , Ácidos Graxos Ômega-3 , Humanos , Ácidos Docosa-Hexaenoicos/metabolismo , Ácidos Docosa-Hexaenoicos/farmacologia , Azidas , Cobre/farmacologia , Biotina/farmacologia , Leucotrieno B4/farmacologia , Ácidos Graxos Ômega-3/farmacologia , Macrófagos , Óleos de Peixe/farmacologia , Anti-Inflamatórios/farmacologia , Alcinos/farmacologia , Prostaglandinas , Oxirredutases
2.
J Med Chem ; 63(20): 11691-11706, 2020 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-32960056

RESUMO

Self-adjuvanting vaccines, wherein an antigenic peptide is covalently bound to an immunostimulating agent, have been shown to be promising tools for immunotherapy. Synthetic Toll-like receptor (TLR) ligands are ideal adjuvants for covalent linking to peptides or proteins. We here introduce a conjugation-ready TLR4 ligand, CRX-527, a potent powerful lipid A analogue, in the generation of novel conjugate-vaccine modalities. Effective chemistry has been developed for the synthesis of the conjugation-ready ligand as well as the connection of it to the peptide antigen. Different linker systems and connection modes to a model peptide were explored, and in vitro evaluation of the conjugates showed them to be powerful immune-activating agents, significantly more effective than the separate components. Mounting the CRX-527 ligand at the N-terminus of the model peptide antigen delivered a vaccine modality that proved to be potent in activation of dendritic cells, in facilitating antigen presentation, and in initiating specific CD8+ T-cell-mediated killing of antigen-loaded target cells in vivo. Synthetic TLR4 ligands thus show great promise in potentiating the conjugate vaccine platform for application in cancer vaccination.


Assuntos
Vacinas Anticâncer/síntese química , Glucosamina/análogos & derivados , Lipídeo A/análogos & derivados , Compostos Organofosforados/química , Ovalbumina/química , Receptor 4 Toll-Like/imunologia , Adjuvantes Imunológicos , Animais , Vacinas Anticâncer/química , Vacinas Anticâncer/imunologia , Citocinas/imunologia , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Glucosamina/química , Glucosamina/imunologia , Imunoglobulina G/sangue , Ligantes , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Compostos Organofosforados/imunologia , Ovalbumina/imunologia , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Vacinas Conjugadas
3.
J Mater Chem B ; 8(32): 7166-7188, 2020 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-32614035

RESUMO

Despite the undeniable advances in recent decades, cancer remains one of the deadliest diseases of the current millennium, where the triple-negative breast cancer (TNBC) is very aggressive, extremely metastatic, and resistant to conventional chemotherapy. The nanotheranostic approach focusing on targeting membrane receptors often expressed at abnormal levels by cancer cells can be a strategic weapon for fighting malignant tumors. Herein, we introduced a novel "all-in-one nanosoldier" made of colloidal hybrid nanostructures, which were designed for simultaneously targeting, imaging, and killing TNBC cells. These nanohybrids comprised four distinct components: (a) superparamagnetic iron oxide nanoparticles, as bi-functional nanomaterials for inducing ferroptosis via inorganic nanozyme-mediated catalysis and magnetotherapy by hyperthermia treatment; (b) carboxymethyl cellulose biopolymer, as a water-soluble capping macromolecule; (c) folic acid, as the membranotopic vector for targeting folate receptors; (d) and doxorubicin (DOX) drug for chemotherapy. The results demonstrated that this novel strategy was highly effective for targeting and killing TNBC cells in vitro, expressing high levels of folate membrane-receptors. The results evidenced that three integrated mechanisms triggered the deaths of the cancer cells in vitro: (a) ferroptosis, by magnetite nanoparticles inducing a Fenton-like reaction; (b) magneto-hyperthermia effect by generating heat under an alternate magnetic field; and (c) chemotherapy, through the DOX intracellular release causing DNA dysfunction. This "all-in-one nanosoldier" strategy offers a vast realm of prospective alternatives for attacking cancer cells, combining multimodal therapy and the delivery of therapeutic agents to diseased sites and preserving healthy cells, which is one of the most critical clinical challenges faced in fighting drug-resistant breast cancers.


Assuntos
Antineoplásicos/química , Doxorrubicina/química , Corantes Fluorescentes/química , Nanopartículas de Magnetita/química , Nanocápsulas/química , Neoplasias de Mama Triplo Negativas/diagnóstico por imagem , Neoplasias de Mama Triplo Negativas/terapia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Terapia Combinada , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Liberação Controlada de Fármacos , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/química , Ácido Fólico/metabolismo , Humanos , Hipertermia Induzida/efeitos adversos , Campos Magnéticos , Nanopartículas de Magnetita/uso terapêutico , Terapia de Alvo Molecular , Imagem Óptica , Estudos Prospectivos , Espécies Reativas de Oxigênio/metabolismo , Nanomedicina Teranóstica
4.
Biomater Sci ; 7(5): 2102-2122, 2019 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-30869664

RESUMO

Glioblastoma is the most aggressive primary brain cancer, which has no cure yet. Emerging nanotheranostic alternatives such as magnetic iron oxide nanoparticles (MIONs) have great potential as multimodal cancer therapy mediators. They can act as nanocarriers of anticancer drugs and generate localized heat when exposed to an alternating magnetic field (AMF), resulting in combined effects of chemotherapy and magnetic hyperthermia therapy. Thus, we designed and synthesized novel MIONs directly through a co-precipitation method by a single step one-pot aqueous green process using carboxymethylcellulose (CMC) as a multifunctional, biocompatible and water-soluble biopolymer ligand (iron oxide nanoparticle-CMC, MION@CMC). They were bioconjugated via amide bonds with doxorubicin (DOX, an anticancer drug) forming nanohybrids (MION@CMC-DOX). The CMC, MION@CMC and MION@CMC-DOX nanoconjugates were comprehensively characterized by 1HNMR, FTIR, TEM/SAED/EDX, UV-visible, XRD, zeta potential (ZP) and DLS analyses. Moreover, cytotoxicity and cell killing activities of these nanoconjugates were assessed by in vitro biological assays. The nanoconjugates were incubated with glioma cells (U87), a magnetic hyperthermia (MHT) assay was performed for evaluating the activity against brain cancer cells and confocal laser scanning laser microscopy was used for bioimaging their cellular uptake pathways. The results showed that fairly monodisperse and water-soluble ultra-small iron oxide nanoparticles (Fe3O4) were synthesized (core size = 7 ± 2 nm) and stabilized by CMC producing negatively charged nanocolloids (-38 ± 3 mV, MION@CMC; hydrodynamic radius, HD = 38 ± 2 nm). The results confirmed the conjugation of MION@CMC with DOX by amide bonds, leading to the development of magnetopolymersome nanostructures (MION@CMC-DOX). The cell viability bioassays evidenced low toxicity of MION@CMC compared to the severe cytotoxicity of MION@CMC-DOX nanosystems mainly caused by the release of DOX. Under an alternating magnetic field, MION@CMC and MION@CMC-DOX systems demonstrated activity for killing U87 cancer cells due to the heat generated by hyperthermia. In addition, the MION@CMC-DOX bioconjugates showed significantly higher cell killing response when exposed to an AMF due to the combined chemotherapy effect of DOX release inside the cancer cells triggering apoptotic pathways.


Assuntos
Antineoplásicos/química , Neoplasias Encefálicas/patologia , Carboximetilcelulose Sódica/química , Doxorrubicina/química , Hipertermia Induzida , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Transporte Biológico , Neoplasias Encefálicas/tratamento farmacológico , Fenômenos Químicos , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Óxido Ferroso-Férrico/química , Células HEK293 , Humanos , Modelos Moleculares , Conformação Molecular , Nanopartículas/química
5.
Chem Commun (Camb) ; 53(86): 11810-11813, 2017 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-29035406

RESUMO

The cysteine hydrolase, N-acylethanolamine acid amidase (NAAA) is a promising target for analgesic and anti-inflammatory drugs. Here, we describe the development of two unprecedented NAAA-reactive activity-based probes as research tools for application in the discovery of new inhibitors and for the in-depth characterization of NAAA in its cellular environment.


Assuntos
Amidoidrolases/metabolismo , Sondas Moleculares/química , Sondas Moleculares/metabolismo , Amidoidrolases/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/farmacologia , Humanos , Sondas Moleculares/síntese química , Estrutura Molecular , Treonina/química , beta-Lactamas/química
6.
J Lipid Res ; 58(12): 2299-2309, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29025868

RESUMO

Epidermal ß-glucocerebrosidase (GBA1), an acid ß-glucosidase normally located in lysosomes, converts (glucosyl)ceramides into ceramides, which is crucial to generate an optimal barrier function of the outermost skin layer, the stratum corneum (SC). Here we report on two developed in situ methods to localize active GBA in human epidermis: i) an optimized zymography method that is less labor intensive and visualizes enzymatic activity with higher resolution than currently reported methods using either substrate 4-methylumbelliferyl-ß-D-glucopyranoside or resorufin-ß-D-glucopyranoside; and ii) a novel technique to visualize active GBA1 molecules by their specific labeling with a fluorescent activity-based probe (ABP), MDW941. The latter method pro-ved to be more robust and sensitive, provided higher resolution microscopic images, and was less prone to sample preparation effects. Moreover, in contrast to the zymography substrates that react with various ß-glucosidases, MDW941 specifically labeled GBA1. We demonstrate that active GBA1 in the epidermis is primarily located in the extracellular lipid matrix at the interface of the viable epidermis and the lower layers of the SC. With ABP-labeling, we observed reduced GBA1 activity in 3D-cultured skin models when supplemented with the reversible inhibitor, isofagomine, irrespective of GBA expression. This inhibition affected the SC ceramide composition: MS analysis revealed an inhibitor-dependent increase in the glucosylceramide:ceramide ratio.


Assuntos
Ensaios Enzimáticos , Corantes Fluorescentes/química , Glucosilceramidase/análise , Pele/enzimologia , Coloração e Rotulagem/métodos , Benzoxazinas/química , Compostos de Boro/química , Cicloexanóis/química , Compostos de Epóxi/química , Expressão Gênica , Glucosídeos/química , Glucosilceramidase/metabolismo , Humanos , Himecromona/análogos & derivados , Himecromona/química , Técnicas de Cultura de Tecidos
7.
J Am Chem Soc ; 139(40): 14192-14197, 2017 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-28937220

RESUMO

Human nonlysosomal glucosylceramidase (GBA2) is one of several enzymes that controls levels of glycolipids and whose activity is linked to several human disease states. There is a major need to design or discover selective GBA2 inhibitors both as chemical tools and as potential therapeutic agents. Here, we describe the development of a fluorescence polarization activity-based protein profiling (FluoPol-ABPP) assay for the rapid identification, from a 350+ library of iminosugars, of GBA2 inhibitors. A focused library is generated based on leads from the FluoPol-ABPP screen and assessed on GBA2 selectivity offset against the other glucosylceramide metabolizing enzymes, glucosylceramide synthase (GCS), lysosomal glucosylceramidase (GBA), and the cytosolic retaining ß-glucosidase, GBA3. Our work, yielding potent and selective GBA2 inhibitors, also provides a roadmap for the development of high-throughput assays for identifying retaining glycosidase inhibitors by FluoPol-ABPP on cell extracts containing recombinant, overexpressed glycosidase as the easily accessible enzyme source.


Assuntos
Ensaios Enzimáticos/métodos , Inibidores Enzimáticos/farmacologia , Polarização de Fluorescência/métodos , Imino Açúcares/farmacologia , beta-Glucosidase/antagonistas & inibidores , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/química , Glucosilceramidase , Humanos , Imino Açúcares/química , beta-Glucosidase/metabolismo
8.
Orthop Traumatol Surg Res ; 102(7): 873-877, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27720193

RESUMO

INTRODUCTION: Femoral nerve block (FNB) is considered as a major advance in anterior cruciate ligament (ACL) reconstruction as it reduces the need for parenteral opioids. However, the incidence of transient or even permanent neurological deficits due to the FNB is estimated at 1.94% after knee surgery. The primary objective of this study was to compare local infiltration analgesia (LIA) to FNB during ACL reconstruction procedures. The study hypothesis was that LIA was not less effective than FNB on early postoperative pain. PATIENTS AND METHODS: A retrospective analysis of data collected prospectively in the FAST cohort included a series of continuous patients who underwent primary repair for isolated ACL with a hamstring graft in 2013-2014. Changes in our anesthesia practices over time allowed us to form three successive groups: Group 1 - FNB, Group 2 - FNB+LIA, Group 3 - LIA only. Ultrasound-guided FNB was done pre-operatively. The LIA was done at the end of the procedure by the surgeon with systematic infiltration of all skin incisions and the hamstring donor site; no intra-articular injections were performed. The primary endpoint was the average early postoperative pain (Days 0-3) described by the patient on a visual analogue scale (0-10). Sample size calculation pointed to 36 subjects being needed per group for a non-inferiority study. RESULTS: The study involved 126 patients: G1=42, G2=38, G3=46. The patients were comparable at enrolment. The average early postoperative pain levels were 3.1±2.4, 2.8±2.0 and 2.5±2.2, respectively (P=0.66). A trend toward higher intake of tramadol was noted in the LIA group on D0 to D3, with a significant trend test on Day 1 (P=0.03) and Day 2 (P=0.02). CONCLUSION: After reconstruction of isolated ACL tears with a hamstring graft, FNB is not more effective than LIA on patients' early postoperative pain. Patients who received a FNB consumed significantly less opioid-like analgesics. LEVEL OF EVIDENCE: III - Prospective, comparative, non-randomized study.


Assuntos
Amidas/administração & dosagem , Anestesia Local/métodos , Anestésicos Locais/administração & dosagem , Reconstrução do Ligamento Cruzado Anterior , Bloqueio Nervoso , Dor Pós-Operatória/prevenção & controle , Adulto , Amidas/uso terapêutico , Anestésicos Locais/uso terapêutico , Feminino , Nervo Femoral , Seguimentos , Humanos , Masculino , Medição da Dor , Dor Pós-Operatória/diagnóstico , Estudos Retrospectivos , Ropivacaina , Resultado do Tratamento
9.
Orphanet J Rare Dis ; 11: 28, 2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27008851

RESUMO

BACKGROUND: We retrospectively compared biochemical responses in type 1 Gaucher disease patients to treatment with glycosphingolipid synthesis inhibitors miglustat and eliglustat and ERT. METHODS: Seventeen GD1 patients were included (n = 6 eliglustat, (two switched from ERT), n = 9 miglustat (seven switchers), n = 4 ERT (median dose 60U/kg/m). Plasma protein markers reflecting disease burden (chitotriosidase, CCL18) and lipids reflecting substrate accumulation (glucosylsphingosine, glucosylceramide) were determined. Also, liver and spleen volumes, hemoglobin, platelets, and fat fraction were measured. RESULTS: In patients naïve to treatment, chitotriosidase, CCL18 and glucosylsphingosine decreased comparably upon eliglustat and ERT treatment, while the response to miglustat was less. After 2 years, median decrease of chitotriosidase was 89% (range 77-98), 88% (78-92) and 37% (29-46) for eliglustat, ERT and miglustat naïve patients respectively; decrease of CCL18 was 73% (63-78), 54% (43-86), and 10% (3-18); decrease of glucosylsphingosine was 86% (78-93), 78% (65-91), 48% (46-50). Plasma glucosylceramide in eliglustat treated patients (n = 4) reached values below the normal range (n = 20 healthy controls). Biochemical markers decreased or stabilized in switchers from ERT to eliglustat (n = 2), but less in miglustat switchers (n = 7). Clinical parameters responded comparably upon eliglustat and ERT treatment. CONCLUSIONS: Our explorative study provides evidence that biochemical markers respond comparably in patients receiving eliglustat treatment and ERT, while the corresponding response to miglustat treatment is less.


Assuntos
Terapia de Reposição de Enzimas/métodos , Doença de Gaucher/tratamento farmacológico , Doença de Gaucher/enzimologia , 1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Feminino , Glucosilceramidase/antagonistas & inibidores , Glucosilceramidase/metabolismo , Glucosilceramidas/metabolismo , Humanos , Masculino , Pirrolidinas/uso terapêutico
10.
J Lipid Res ; 56(4): 927-35, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25684760

RESUMO

The endocannabinoid 2-arachidonoylglycerol (2-AG) is predominantly biosynthesized by sn-1-diacylglycerol lipase α (DAGL-α) in the CNS. Selective inhibitors of DAGL-α will provide valuable insights in the role of 2-AG in endocannabinoid signaling processes and are potential therapeutics for the treatment of obesity and neurodegenerative diseases. Here, we describe the development of a natural substrate-based fluorescence assay for DAGL-α, using a coupled enzyme approach. The continuous setup of our assay allows monitoring of DAGL-α activity in real-time and in a 96-well plate format. This constitutes a major improvement to the currently available radiometric and LC/MS-based methods, which can be executed only in low-throughput formats. In addition, our assay circumvents the use of radioactive material. We demonstrate that our assay can be used to screen inhibitors of DAGL-α activity, using 1-stearoyl-2-arachidonoyl-sn-glycerol as the physiologically relevant natural substrate of DAGL-α. Furthermore, our method can be employed to measure DAGL activity and inhibition in the mouse brain membrane proteome. Consequently, our assay should serve as a valuable tool for rapid hit validation and lead optimization of DAGL-α inhibitors.


Assuntos
Diglicerídeos/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Inibidores Enzimáticos/farmacologia , Lipase Lipoproteica/antagonistas & inibidores , Lipase Lipoproteica/metabolismo , Animais , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Cinética , Camundongos , Espectrometria de Fluorescência
11.
Top Curr Chem ; 301: 253-89, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21222193

RESUMO

This chapter describes the assembly of uronic acid containing oligosaccharides and glycoconjugates. Two strategies are available to access these target molecules, namely a pre-glycosylation oxidation approach, in which uronic acid building blocks are used, and a post-glycosylation oxidation strategy, which employs an oxidation step after the assembly of the oligosaccharide chain. Because uronic acid building blocks are generally considered to be less reactive than their non-oxidized counterparts, the latter approach has found most application in carbohydrate synthesis. With the aid of selected examples of recent syntheses of biologically relevant oligosaccharides and glycoconjugates, the reactivity of different uronic acid building blocks is evaluated. From these examples it is apparent that the generally assumed low reactivity of uronic acids does not a priori rule out an efficient assembly of these target compounds. Besides influencing the reactivity of a given pyranoside, the C-5 carboxylic acid function can also have a profound effect on the stereochemical course of a glycosylation reaction, which can be exploited in the stereoselective formation of glycosidic bonds.


Assuntos
Glicoconjugados/síntese química , Oligossacarídeos/síntese química , Ácidos Urônicos/química , Alginatos/síntese química , Pectinas/síntese química , Saponinas/síntese química
12.
Knee Surg Sports Traumatol Arthrosc ; 18(6): 777-80, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19784623

RESUMO

Our case report highlights the complexity of treating multi-ligament knee injuries in the setting of ipsilateral long bone trauma. We describe the use of the tibial inlay technique for PCL reconstruction in the setting of a tibial shaft fracture treated with an intramedullary nail. We also present a comprehensive treatment algorithm for the treatment of ligamentous knee injuries in the setting of long bone trauma.


Assuntos
Algoritmos , Fixação Intramedular de Fraturas/métodos , Luxação do Joelho/cirurgia , Ligamento Cruzado Posterior/lesões , Ligamento Cruzado Posterior/cirurgia , Fraturas da Tíbia/cirurgia , Adulto , Pinos Ortopédicos , Procedimentos Clínicos , Fixação Intramedular de Fraturas/instrumentação , Humanos , Luxação do Joelho/complicações , Masculino , Fraturas da Tíbia/complicações
13.
Bioorg Med Chem Lett ; 19(23): 6600-3, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19853441

RESUMO

In the recent past sugar-derived cyclopropylamines were proposed as structurally new glycosidase inhibitors. In this Letter we report our efforts in the synthesis of a set of alpha-glucose configured oxabicyclo[4.1.0] heptanes, based on this hypothesis, bearing an amine substituent on the propyl ring and reveal that their inhibitory potential towards a range of mammalian glucosidases is modest.


Assuntos
Aminas/síntese química , Aminas/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Glucosidases/antagonistas & inibidores , Aminas/química , Compostos Bicíclicos Heterocíclicos com Pontes/química , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Conformação Molecular , Relação Estrutura-Atividade
14.
Org Biomol Chem ; 5(9): 1416-26, 2007 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-17464411

RESUMO

The synthesis and evaluation of hybrid proteasome inhibitors that contain structural elements of the known inhibitors bortezomib, epoxomicin and peptide vinyl sulfones is described. From the panel of 15 inhibitors some structure activity relationships can be deduced with regard to inhibitory activity in relation to peptide recognition element, inhibitor size and nature of the electrophilic trap. Further, the panel contains one of the most potent peptide-based pan-proteasome inhibitors reported to date.


Assuntos
Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Inibidores de Proteassoma , Linhagem Celular , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/química , Humanos , Complexo de Endopeptidases do Proteassoma/metabolismo , Eletricidade Estática , Relação Estrutura-Atividade
15.
Food Nutr Bull ; 23(3 Suppl): 158-65, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12362786

RESUMO

The fortification of various types of food with minerals is often undertaken without consideration of either their bioavailability or the potential nutrient-nutrient interactions resulting from their use. Stable isotopes provide a safe and accessible method of resolving these issues by providing the proper evidence in each case. They must be conducted according to strict safety and ethical guidelines and may be readily conducted in a field setting. Clinical studies in children enable researchers, policymakers, and food manufacturers to obtain the data necessary to determine the best way to fortify specific foods and beverages, in order to optimally enhance the nutritional health of growing children. We have shown the utility of this approach in studies in both developing countries and in the United States.


Assuntos
Alimentos Fortificados , Minerais/farmacocinética , Disponibilidade Biológica , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/farmacocinética , Criança , Países em Desenvolvimento , Interações Medicamentosas , Grão Comestível , Humanos , Indonésia , Ferro da Dieta/administração & dosagem , Ferro da Dieta/farmacocinética , Isótopos , Magnésio/administração & dosagem , Magnésio/farmacocinética , Minerais/administração & dosagem , Valor Nutritivo , Segurança , Estados Unidos , Zinco/administração & dosagem , Zinco/farmacocinética
16.
Plant Physiol ; 127(1): 78-89, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11553736

RESUMO

The interaction between the tropical legume Sesbania rostrata and the bacterium Azorhizobium caulinodans results in the formation of nodules on both stem and roots. Stem nodulation was used as a model system to isolate early markers by differential display. One of them, Srchi24 is a novel early nodulin whose transcript level increased already 4 h after inoculation. This enhancement depended on Nod factor-producing bacteria. Srchi24 transcript levels were induced also by exogenous cytokinins. In situ hybridization and immunolocalization experiments showed that Srchi24 transcripts and proteins were present in the outermost cortical cell layers of the developing nodules. Sequence analyses revealed that Srchi24 is similar to class III chitinases, but lacks an important catalytic glutamate residue. A fusion between a maltose-binding protein and Srchi24 had no detectable hydrolytic activity. A function in nodulation is proposed for the Srchi24 protein.


Assuntos
Quitinases/química , Fabaceae/microbiologia , Proteínas de Membrana , Proteínas de Plantas/genética , Sequência de Aminoácidos , Azorhizobium caulinodans/fisiologia , Citocininas/farmacologia , DNA Bacteriano , DNA Complementar , Regulação da Expressão Gênica de Plantas , Ácido Glutâmico/metabolismo , Hidrólise , Hibridização In Situ , Lipopolissacarídeos/metabolismo , Dados de Sequência Molecular , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Caules de Planta/metabolismo , Caules de Planta/microbiologia , Homologia de Sequência de Aminoácidos , Simbiose/genética
17.
J Behav Health Serv Res ; 27(3): 286-302, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10932442

RESUMO

A randomized experimental design was used to assign participants to an integrated mental health and substance use treatment program or to standard hospital treatment. A multilevel, nonlinear model was used to estimate hospital treatment effects on days of alcohol use for persons with serious mental illness and substance use disorders over 18 months. The integrated treatment program had a significant effect on the rate of alcohol use at 2 months postdischarge, reducing the rate of use by 54%. Motivation for sobriety at hospital discharge, posttreatment self-help attendance, and social support for sobriety were also found to reduce the rate of use during the follow-up period. Implications for mental health treatment and aftercare support are discussed.


Assuntos
Alcoolismo/reabilitação , Prestação Integrada de Cuidados de Saúde , Transtornos Mentais/reabilitação , Transtornos Relacionados ao Uso de Substâncias/reabilitação , Adulto , Comorbidade , Diagnóstico Duplo (Psiquiatria) , Feminino , Seguimentos , Hospitais Psiquiátricos , Humanos , Masculino , Pessoa de Meia-Idade , Dinâmica não Linear , Resultado do Tratamento
18.
J Bone Joint Surg Br ; 82(3): 352-7, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10813168

RESUMO

We describe three prostheses with cemented titanium-alloy stems and Al2O3 ceramic femoral heads which had to be revised after a mean period of implantation of 78 months. In each case, the neck of the prosthesis had been so severely worn that the profile was elliptical rather than circular. There was severe metallosis of the periprosthetic tissues. Metal particles isolated from the tissues were approximately one nanometre in size and the ratios of titanium, aluminium and vanadium in the particles were the same as in the original alloy. Histologically, the high concentration of metal particles masked the presence of high-density polyethylene (HDP) debris, but again particles about one nanometre in size were isolated from the tissues. The severe necrobiosis and necrosis noted were consistent with other reports of the presence of extensive wear particles in periprosthetic tissues. Wear is presumed to have occurred as a result of mismatch between the shape or size of the taper cone and the femoral head, or to changes in the geometry of loading due to migration of the cup. To facilitate early intervention, patients with this design of prosthesis should be monitored radiologically.


Assuntos
Óxido de Alumínio , Análise de Falha de Equipamento , Reação a Corpo Estranho/patologia , Prótese de Quadril , Complicações Pós-Operatórias/patologia , Titânio , Idoso , Idoso de 80 Anos ou mais , Ligas , Feminino , Reação a Corpo Estranho/cirurgia , Articulação do Quadril/patologia , Humanos , Masculino , Microscopia Eletrônica de Varredura , Necrose , Complicações Pós-Operatórias/cirurgia , Desenho de Prótese , Falha de Prótese , Reoperação
19.
Planta ; 209(1): 45-52, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10467030

RESUMO

During a search for genes with induced or enhanced expression in the early stages of development of stem-borne nodules on Sesbania rostrata, a cDNA with homology to chalcone reductase (CHR) genes was isolated. Here, we describe the characterization of a full-length CHR cDNA (Srchr1) and the pattern of CHR transcript accumulation in stem-borne nodules. Expression was correlated with both nodule development and bacterial invasion. In young nodules, CHR transcripts were observed in cells of the parenchyma, in cells around the nodule vascular bundles, and in the uninfected cells of the central tissue.


Assuntos
Oxirredutases do Álcool/genética , Fabaceae/enzimologia , Plantas Medicinais , Sequência de Aminoácidos , Azorhizobium caulinodans/fisiologia , Sequência de Bases , DNA de Plantas , Fabaceae/genética , Hibridização In Situ , Dados de Sequência Molecular , Caules de Planta/enzimologia , RNA Mensageiro/metabolismo , RNA de Plantas/metabolismo , Homologia de Sequência de Aminoácidos , Clima Tropical
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