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1.
Food Funct ; 8(8): 2722-2730, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28725891

RESUMO

A comparison between the impacts of advanced (Nε-carboxymethyllysine - CML) and terminal (melanoidins) Maillard reaction products from bread on gut microbiota was carried out in this study. Gut microbiota composition as well as fecal excretion of CML from both bread crust and bread crumb, and of melanoidins from bread crust were assessed on a rodent model. Rats were fed with pellets supplemented or not with 13% of bread crust, bread crumb, a fiber-free bread crust model (glucose, starch and gluten heated together) or a fiber-free-melanoidin-free bread model (glucose-starch and gluten heated separately) for four weeks. These model systems were developed to limit the presence of wheat-native dietary fibers such as cellulose, hemicelluloses and lignin. CML and melanoidins in pellets and feces were evaluated by LC/MS-MS and HPLC/fluorescence respectively, and gut microbiota composition was determined by cultivation and molecular approaches. Diets supplemented with crumb or the fiber-free-melanoidin-free model contained respectively 17% and 64% less melanoidins than their respective controls. A higher excretion of melanoidins was observed for rats fed with crust or bread crust model compared to their controls, confirming that melanoidins are in contact with gut microbiota. No impact of diets was observed on Firmicutes, Bacteroidetes and lactic flora. A decrease of enterobacteria was only observed for rats fed with the diet supplemented with the fiber-free bread crust model. Moreover, a significant increase of bifidobacteria numbers in the presence of crust, crumb and both bread models was observed, showing that this bifidogenic effect of bread is not due to the presence of melanoidins or wheat-native dietary fibers.


Assuntos
Bactérias/isolamento & purificação , Pão/análise , Fezes/química , Microbioma Gastrointestinal , Triticum/química , Triticum/metabolismo , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Fezes/microbiologia , Lisina/análogos & derivados , Lisina/química , Lisina/metabolismo , Reação de Maillard , Masculino , Polímeros/química , Polímeros/metabolismo , Ratos , Ratos Sprague-Dawley
2.
J Blood Disord Transfus ; 4(5)2013 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-25309814

RESUMO

BACKGROUND: Endothelial progenitor cells (EPC) are markers of endothelial injury and may serve as a surrogate marker for vascular repair in interventional clinical trials. Objectives of this study were to modify a method of isolation of peripheral blood mononuclear cells (PBMC) and enumeration of EPC and mature endothelial cells (EC) from peripheral blood and to evaluate influence of cryopreservation on viability of PBMC and on numbers of EPC and EC. PATIENTS/METHODS: EPC and EC were analyzed in healthy volunteers in freshly isolated PBMC collected in CPT (cell preparation tubes) and in PBMC cryopreserved with: 1) Gibco Recovery™ Cell Culture Freezing Medium, 2) custom freezing medium. Viability of PBMC was tested using DAPI. EPC were gated for CD45- CD34+CD133+/-VEGFR2+/- and EC were gated for CD45-CD146+CD34+/-VEGFR2+/-. RESULTS: Cryopreservation for 7 days at -80°C decreased viable PBMC from 94 ± 0.5% (fresh) to 84 ± 4% (the custom medium) and to 69 ± 8% (Gibco medium), while cryopreservation at -65°C decreased viability to 60 ± 6% (p<0.001, the custom medium) and 49 ± 5% (p<0.001, Gibco medium). In fresh samples early EPC (CD45- CD34+CD133+VEGFR2+) were enumerated as 0.2 ± 0.06%, late EPC(CD45-CD146+CD34+VEGFR2+) as 0.6 ± 0.1% and mature EC (CD45-CD146+CD34-VEGFR2+) as 0.8 ± 0.3%of live PBMC. Cryopreservation with Gibco and the custom freezing medium at -80°C for 7 days decreased numbers EPC and EC, however, this decrease was not statistically significant. CONCLUSIONS: Our data indicate that cryopreservation at -80°C for 7 days decreases, although not significantly, viability of PBMC and numbers of subsets of EC and EPC. This method may provide an optimized approach to isolation and short-term cryopreservation of subsets of EPC and of mature EC suitable for multicenter trials.

3.
Neurology ; 75(23): 2059-62, 2010 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-21135380

RESUMO

OBJECTIVES: Circulating endothelial progenitor cells (EPC) are markers of vascular injury and their numbers decrease in acute stroke. However, the relation of EPC levels to stroke severity has not been quantified. MRI measurements of lesion volume provide an objective method for stroke severity assessment and outcome prediction. This cross-sectional study aims to determine whether EPC are correlated with lesion volume at baseline, lesion growth, and final lesion volume. METHODS: Seventeen patients (median age 63 years, NIH Stroke Scale score 7) were selected from 175 patients with imaging-confirmed acute ischemic stroke. EPC were quantified by flow cytometry using CD34, CD133, and VEGFR2 surface markers. Brain MRI was performed at baseline and at days 1 and 5 after the stroke onset. Stroke lesion volumes were quantified. RESULTS: Larger lesion volumes measured on diffusion-weighted images (DWI) at baseline were associated with low EPC levels, while smaller lesion volumes and less lesion growth were linked with high levels of EPC subsets (CD34+CD133+, CD133+VEGFR2+, and CD34+ CD133+VEGFR2+). Similar results were observed with DWI lesion volumes and EPC (CD34+CD133+) on day 1. Lesion growth volume, represented as a difference between final lesion volume and baseline DWI, was larger in patients with lower day 1 EPC (CD133+VEGFR2+). After adjustments for age and admission glucose (model 1), mean arterial pressure and white blood cells (model 2), INR and hematocrit (model 3), the CD34+CD133+ subset remained predictive of baseline and day 1 lesion volumes, while CD133+VEGFR2+ predicted baseline lesion volume and growth of lesion volume. CONCLUSIONS: Higher EPC levels were indicative of smaller volumes of acute lesion, final lesion, and lesion growth, and may serve as markers of acute phase stroke severity. However, a larger prospective study is needed to confirm our findings.


Assuntos
Encéfalo/patologia , Células Endoteliais/patologia , Células-Tronco/patologia , Acidente Vascular Cerebral/patologia , Idoso , Antígenos CD/metabolismo , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo
4.
J Physiol Pharmacol ; 57 Suppl 11: 133-44, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17244945

RESUMO

Vascular endothelial cells are important not only for maintaining homeostasis, but also in pathogenesis of vascular disorders. Cerebral capillary and microvascular endothelial cells play an active role in maintaining cerebral blood flow, microvascular tone and blood brain barrier functions. Factors produced and released by endothelial cells, other brain cells and circulating blood cells participate in these regulatory functions. In particular, endothelin-1 (ET-1) and nitric oxide (NO) are known to contribute to the functional vascular changes under pathological conditions (e.g., hypertension, arteriosclerosis, and stroke). This report describes the involvement of endothelial cell mediators in the post-ischemic hypoperfusion induced by brain ischemia and in vitro endothelial responses (Ca(2+) mobilization and cytoskeletal rearrangements) to ET-1 and its interactions with NO or 2-AG. The capacity of NO and endocannabinoids to counteract ET-1-induced cerebral capillary and microvascular endothelial responses indicates that they may actively participate in EC function and implicates them in physiological and pathophysiological conditions.


Assuntos
Encéfalo/irrigação sanguínea , Endotelina-1/fisiologia , Endotélio Vascular/fisiopatologia , Actinas/metabolismo , Análise de Variância , Animais , Ácidos Araquidônicos/fisiologia , Barreira Hematoencefálica , Isquemia Encefálica/etiologia , Isquemia Encefálica/fisiopatologia , Cálcio/metabolismo , Células Cultivadas , Citoesqueleto/metabolismo , Endocanabinoides , Endotelina-1/metabolismo , Endotélio Vascular/metabolismo , Gerbillinae , Glicerídeos/fisiologia , Humanos , Imuno-Histoquímica , Microcirculação , Óxido Nítrico/fisiologia , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/fisiopatologia
6.
Am J Physiol Cell Physiol ; 284(2): C243-9, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12529247

RESUMO

Previous studies have demonstrated that functional interaction between endothelin (ET)-1 and nitric oxide (NO) involves changes in Ca(2+) mobilization and cytoskeleton in human brain microvascular endothelial cells. The focus of this investigation was to examine the possible existence of analogous interplay between these vasoactive substances and elucidate their signal transduction pathways in human brain capillary endothelial cells. The results indicate that ET-1-stimulated Ca(2+) mobilization in these cells is dose-dependently inhibited by NOR-1 (an NO donor). This inhibition was prevented by ODQ (an inhibitor of guanylyl cyclase) or Rp-8-CPT-cGMPS (an inhibitor of protein kinase G). Treatment of endothelial cells with 8-bromo-cGMP reduced ET-1-induced Ca(2+) mobilization in a manner similar to that observed with NOR-1 treatment. In addition, NOR-1 or cGMP reduced Ca(2+) mobilization induced by mastoparan (an activator of G protein), inositol 1,4,5-trisphosphate, or thapsigargin (an inhibitor of Ca(2+)-ATPase). Interestingly, alterations in endothelial cytoskeleton (actin and vimentin) were associated with these effects. The data indicate for the first time that the cGMP-dependent protein kinase colocalizes with actin. These changes were accompanied by altered levels of phosphorylated vasodilator-stimulated phosphoprotein, which were elevated in endothelial cells incubated with NOR-1 and significantly reduced by ODQ or Rp-8-CPT-cGMPS. The findings indicate a potential mechanism by which the functional interrelationship between ET-1 and NO plays a role in regulating capillary tone, microcirculation, and blood-brain barrier function.


Assuntos
Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Endotelina-1/metabolismo , Endotélio Vascular/metabolismo , Óxido Nítrico/metabolismo , Actinas/efeitos dos fármacos , Actinas/metabolismo , Arginina/farmacologia , Encéfalo/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Moléculas de Adesão Celular/efeitos dos fármacos , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Proteínas Quinases Dependentes de GMP Cíclico/efeitos dos fármacos , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Relação Dose-Resposta a Droga , Antagonistas dos Receptores de Endotelina , Endotelina-1/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Imuno-Histoquímica , Proteínas dos Microfilamentos , Doadores de Óxido Nítrico/farmacologia , Fosfoproteínas/efeitos dos fármacos , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Receptor de Endotelina A , Receptores de Endotelina/metabolismo , Transdução de Sinais/fisiologia
7.
Acta Neurochir Suppl ; 86: 271-5, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14753451

RESUMO

Reactive oxygen species (ROS) were shown to play a role in altering blood-brain barrier (BBB) permeability and formation of brain edema induced by trauma and/or ischemia. 2-arachidonoyl glycerol (2-AG), a novel, potent vasodilatory and cytoprotective endocannabinoid has been implicated to act as an antioxidative agent. This study examines: 1) the possible 2-AG modulation of BBB injury and edema formation induced by closed head injury (CHI); and 2) comparable effects between 2-AG and 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (TPL), a known antioxidant nitroxide on endothelial Ca2+ and cytoskeletal responses to H2O2 (ROS). 2-AG treatment reduced the CHI-induced increase in BBB permeability and brain edema. The endothelial H2O2-stimulated Ca2+ mobilization and cytoskeleton (vimentin) rearrangement was modified by either 2-AG or TPL. These findings provide evidence of 2-AG antioxidant activity and are consistent with the involvement of ROS in the pathomechanism of CHI-induced BBB injury and brain edema.


Assuntos
Antioxidantes/farmacologia , Ácidos Araquidônicos/farmacologia , Barreira Hematoencefálica , Edema Encefálico/etiologia , Moduladores de Receptores de Canabinoides/farmacologia , Endocanabinoides , Glicerídeos/farmacologia , Traumatismos Cranianos Fechados/complicações , Traumatismos Cranianos Fechados/fisiopatologia , Sistema Vasomotor/efeitos dos fármacos , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Cálcio/metabolismo , Permeabilidade Capilar/efeitos dos fármacos , Óxidos N-Cíclicos/farmacologia , Citoesqueleto/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Sequestradores de Radicais Livres/farmacologia , Peróxido de Hidrogênio/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos , Oxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Marcadores de Spin
8.
J Neural Transm Suppl ; (62): 189-202, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12456063

RESUMO

The M1 muscarinic agonists AF102B, AF150(S) & AF267B--i) restored cognitive impairments in several animal models for AD with an excellent safety margin; ii) elevated alpha-APPs levels; iii) attenuated vicious cycles induced by A beta, and inhibited A beta- and oxidative stress-induced apoptosis; and iv) decreased tau hyperphosphorylation. AF150(S) and AF267B were more effectve than rivastigmine and nicotine in restoring memory impairments in mice with small hippocampi. In apolipoprotein E-knockout mice, AF150(S) restored cognitive impairments and cholinergic hypofunction and decreased tau hyperphosphorylation. In aged microcebes, AF150(S) restored cognitive and behavioral impairments and decreased tau hyperphosphorylation, paired helical filaments and astrogliosis. In rabbits, AF267B & AF150(S) decreased CSF A beta(1-42 & 1-40), while AF102B reduced A beta(1-40). Finally AF102B decreased CSF A beta(total) in AD patients. Taken together, M1 agonists may represent a unique therapy in AD due to their beneficial effects on three major hallmarks of AD--cholinergic hypofunction, A beta and tau protein hyperphosphorylation.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Agonistas Muscarínicos/uso terapêutico , Idoso , Humanos
9.
Sci STKE ; 2002(129): re5, 2002 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-11972360

RESUMO

Traumatic brain injury (TBI) releases harmful mediators that lead to secondary damage. On the other hand, neuroprotective mediators are also released, and the balance between these classes of mediators determines the final outcome after injury. Recently, it was shown that the endogenous brain cannabinoids anandamide and 2-Arachidonoyl glycerol (2-AG) are also formed after TBI in rat and mouse respectively, and when administered after TBI, they reduce brain damage. In the case of 2-AG, better results are seen when it is administered together with related fatty acid glycerol esters. Significant reduction of brain edema, better clinical recovery, and reduced infarct volume and hippocampal cell death are noted. This new neuroprotective mechanism may involve inhibition of transmitter release and of inflammatory response. 2-AG is also a potent modulator of vascular tone, and counteracts the endothelin (ET-1)-induced vasoconstriction that aggravates brain damage; it may thus help to restore blood supply to the injured brain.


Assuntos
Dano Encefálico Crônico/etiologia , Dano Encefálico Crônico/prevenção & controle , Lesões Encefálicas/complicações , Lesões Encefálicas/fisiopatologia , Canabinoides/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Animais , Química Encefálica/fisiologia , Dano Encefálico Crônico/metabolismo , Lesões Encefálicas/metabolismo , Moduladores de Receptores de Canabinoides , Canabinoides/metabolismo , Endocanabinoides , Humanos , Estrutura Molecular , Fármacos Neuroprotetores/metabolismo
10.
J Steroid Biochem Mol Biol ; 76(1-5): 85-93, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11384866

RESUMO

The phenomenon of mutual annihilation of action between 17beta estradiol (E(2)) and a selective estrogen receptor modulator (SERM), previously described in prepubertal rat diaphysis, epiphysis and uterus, has been investigated in ROS 17/2.8 rat osteoblastic cells and in transiently co-transfected cells in culture. In ROS 17/2.8 cells, the estrogen-induced marker enzyme creatine kinase B (CKB) was stimulated by raloxifene, tamoxifen and tamoxifen methiodide to a specific activity equal to or greater than that induced by 10 nM E(2). However, when a fully inhibitory dose of any of these SERMS was given simultaneously with E(2), no stimulation of CK activity resulted. Therefore, SERMS can be full agonists when acting alone, but complete antagonists to a super-physiological dose of estrogen. It is expected that excess tamoxifen would prevent the action of a SERM, but that the agonist activity of a SERM is abolished by 1000-fold less estrogen is a phenomenon without obvious explanation by classical pharmacology of competitive inhibition. To probe the mechanism of this interaction further, a ckb-CAT reporter plasmid, plus the human receptor expression plasmid, HEO, was transfected transiently into several cell types. In MCF-7 cells, a 1:10 ratio of E(2) to tamoxifen produced mutual annihilation, but the same ratio in ROS 17/2.8 or HeLa cells led to synergistic stimulation. In HeLa cells, co-transfected with the more efficient wild-type estrogen receptor plasmid, HEGO, synergy was demonstrated only at sub-saturation levels of HEGO. We speculate that, in the presence of estradiol and a SERM, not only active homodimers would be formed, but also hetero-dimers of estrogen-liganded and tamoxifen-liganded receptor monomers, depending on the molar ratio of their ligands and their relative affinities. The resulting hetero-dimer conformation would change the specific receptor surface for interactions with the growing number of co-activators and co-repressors, structural changes which could help to explain the mutual annihilation and synergy phenomena and their cell selectivity.


Assuntos
Estrogênios/fisiologia , Receptores de Estrogênio/fisiologia , Antineoplásicos Hormonais/farmacologia , Creatina Quinase/metabolismo , Humanos , Ligantes , Neoplasias/enzimologia , Neoplasias/patologia , Receptores de Estrogênio/efeitos dos fármacos , Tamoxifeno/farmacologia , Transfecção , Células Tumorais Cultivadas
11.
Brain Res ; 895(1-2): 59-65, 2001 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-11259760

RESUMO

Intravenous administration of lipopolysaccharide (LPS) (0.9 mg/kg) has been shown to induce ischemic tolerance in spontaneously hypertensive rats (SHR). TNF-alpha is believed to play a crucial role in preconditioning as its inhibition with TNF-alpha-binding protein abolished tolerance. Our recent studies (Liu et al., Am. J. Physiol. 278 C144, 2000) have demonstrated that ceramide, a downstream messenger in TNF-alpha signaling, is a mediator of hypoxia-induced tolerance in neuronal cells. To test the hypothesis that ceramide contributes to LPS-induced tolerance in vivo, SHR were injected intravenously with either LPS or saline and the levels of ceramide in brain and in plasma were determined by reversed phase HPLC. LPS injection resulted in a significant increase of ceramide in plasma with a maximum at 24 h (8.32+/-1.14 pmol/microl (LPS) vs. 2.65+/-0.62 pmol/microl (saline)). LPS also induced ceramide upregulation in brain cortex, which started between 6 and 12 h and remained elevated up to 48 h after LPS injection. Fluorescent NBD-C6 ceramide was able to cross blood-brain barrier and was found in brain vessels, perivascular cells and in brain parenchyma 30 min after intravenous injection. These findings demonstrate that LPS preconditioning leads to elevation of ceramide in brain and plasma and, in conjunction with previous work, suggests that ceramide plays a role in LPS-induced protection against brain ischemic injury in vivo.


Assuntos
4-Cloro-7-nitrobenzofurazano/análogos & derivados , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Encéfalo/efeitos dos fármacos , Ceramidas/sangue , Precondicionamento Isquêmico , Lipopolissacarídeos/farmacologia , Fármacos Neuroprotetores/farmacologia , 4-Cloro-7-nitrobenzofurazano/farmacologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiologia , Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/fisiologia , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Encéfalo/irrigação sanguínea , Encéfalo/fisiopatologia , Isquemia Encefálica/fisiopatologia , Ceramidas/farmacologia , Circulação Cerebrovascular/efeitos dos fármacos , Circulação Cerebrovascular/fisiologia , Modelos Animais de Doenças , Corantes Fluorescentes/farmacologia , Interleucina-6/sangue , Leucócitos/citologia , Leucócitos/efeitos dos fármacos , Leucócitos/metabolismo , Ratos , Ratos Endogâmicos SHR , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Fator de Necrose Tumoral alfa/metabolismo
12.
J Neurosci Res ; 62(4): 480-90, 2000 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11070491

RESUMO

Vasopressin (AVP) influences non-neuronal brain cells in cell-type specific manners: (1) it regulates water balance at the cellular level of brain parenchyma by adjusting astrocytic water permeability; (2) it contributes to the control of extracellular K(+) concentration ([K(+)](e)) in brain by stimulation of K(+) transfer from blood to brain, due to activation of an inwardly directed Na(+),K(+),Cl(-) cotransporter at the luminal membrane of capillary endothelial cells and opening of K(+) channels at their abluminal membrane; (3) it decreases formation of cerebrospinal fluid (CSF) by decreasing Cl(-) secretion into CSF by epithelial cells of the choroid plexus, probably by inhibition of Cl(-)/HCO(-)(3) exchange at their basolateral membrane; (4) it contributes to regulation of intracellular volume within the brain by regulation of water permeability in ependymal cells and subpial astrocytes; and (5) it exerts effects on specialized astrocytes in circumventricular organs, their adjacent glia limitans, and the neural pituitary, which regulate AVP release to the systemic circulation by altering the spatial relationship between neurons and their adjacent glial cells. A unified mechanism is proposed, which integrates most of the effects of AVP and may be of considerable importance for neuronal excitability and, thus, for behavior.


Assuntos
Arginina Vasopressina/metabolismo , Astrócitos/metabolismo , Encéfalo/metabolismo , Plexo Corióideo/metabolismo , Endotélio Vascular/metabolismo , Epêndima/metabolismo , Equilíbrio Hidroeletrolítico/fisiologia , Animais , Astrócitos/citologia , Encéfalo/citologia , Ventrículos Cerebrais/citologia , Ventrículos Cerebrais/metabolismo , Plexo Corióideo/citologia , Endotélio Vascular/citologia , Epêndima/citologia , Espaço Extracelular/metabolismo , Homeostase/fisiologia , Humanos , Íons/metabolismo , Neurônios/metabolismo , Permeabilidade , Neuro-Hipófise/citologia , Neuro-Hipófise/metabolismo
13.
Bull Med Libr Assoc ; 88(4): 382-8, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11055307

RESUMO

Both lifestyle and geography make the delivery of consumer health information in the rural setting unique. The Planetree Health Resource Center in The Dalles, Oregon, has served the public in a rural setting for the past eight years. It is a community-based consumer health library, affiliated with a small rural hospital, Mid-Columbia Medical Center. One task of providing consumer health information in rural environments is to be in relationship with individuals in the community. Integration into community life is very important for credibility and sustainability. The resource center takes a proactive approach and employs several different outreach efforts to deepen its relationship with community members. It also works hard to foster partnerships for improved health information delivery with other community organizations, including area schools. This paper describes Planetree Health Resource Center's approach to rural outreach.


Assuntos
Relações Comunidade-Instituição , Educação em Saúde , Serviços de Informação , Serviços de Biblioteca , Saúde da População Rural , Exposições Educativas , Internet , Estilo de Vida , Oregon
14.
J Med Virol ; 62(1): 29-36, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10935985

RESUMO

The specific immune responses directed against the viral single stranded (ss) DNA binding protein ICP8 and the transactivator of immediate early (IE) gene expression VP16 (alpha-trans inducing factor, Vmw65) in HSV type 1 seropositive humans were examined. The results described in this paper indicate that neither ICP8 nor VP16 were able to induce a recall response in lymphocytes of healthy HSV seropositive individuals without recurrent infection, although CD4+ T cells purified from these individuals responded to both viral proteins in vitro when monocyte derived dendritic cells were used as antigen presenting cells. A recall response, however, could be induced to both viral proteins in T cells of patients with recurrent HSV infections when blood monocytes were used. Moreover, ICP8- and VP16-specific antibodies could be detected in the serum of patients with recurrent HSV infections whereas, in contrast, these antibodies were virtually absent in healthy HSV seropositive individuals without recurrences. These data represent the first systematic study of the immunological properties of ICP8 in humans, indicating a significant difference in the response to the essential viral regulators ICP8 and VP16 in HSV-1 seropositive healthy individuals as opposed to patients with recurrent HSV-1 infections.


Assuntos
Proteínas de Ligação a DNA/imunologia , Proteína Vmw65 do Vírus do Herpes Simples/imunologia , Herpes Simples/imunologia , Herpesvirus Humano 1/imunologia , Proteínas Virais/imunologia , Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Linfócitos T CD4-Positivos/imunologia , Feminino , Citometria de Fluxo , Imunofluorescência , Humanos , Immunoblotting , Masculino , Monócitos/imunologia , Recidiva , Testes Sorológicos
15.
Circ Res ; 87(4): 323-7, 2000 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-10948067

RESUMO

In brain, the regulatory mechanism of the endothelial reactivity to nitric oxide and endothelin-1 may involve Ca(2+), cytoskeleton, and vasodilator-stimulated phosphoprotein changes mediated by the cGMP/cGMP kinase system.(1) Endothelium of human brain capillaries or microvessels is used to examine the interplay of endothelin-1 with the putative vasorelaxant 2-arachidonoyl glycerol, an endogenous cannabimimetic derivative of arachidonic acid. This study demonstrates that 2-arachidonoyl glycerol counteracts Ca(2+) mobilization and cytoskeleton rearrangement induced by endothelin-1. This event is independent of nitric oxide, cyclooxygenase, and lipoxygenase and is mediated in part by cannabimimetic CB1 receptor, G protein, phosphoinositol signal transduction pathway, and Ca(2+)-activated K(+) channels. The induced rearrangements of cellular cytoskeleton (actin or vimentin) are partly prevented by inhibition of protein kinase C or high levels of potassium chloride. The 2-arachidonoyl glycerol-induced phosphorylation of vasodilator-stimulated phosphoprotein is mediated by cAMP. These findings suggest that 2-arachidonoyl glycerol may contribute to the regulation of cerebral capillary and microvascular function.


Assuntos
Ácidos Araquidônicos , Encéfalo/irrigação sanguínea , Endotelina-1/metabolismo , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Glicerídeos/farmacologia , Neurotransmissores/farmacologia , Actinas/metabolismo , Encéfalo/metabolismo , Cálcio/metabolismo , Moduladores de Receptores de Canabinoides , Capilares/citologia , Capilares/efeitos dos fármacos , Capilares/metabolismo , Moléculas de Adesão Celular/metabolismo , Células Cultivadas , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Relação Dose-Resposta a Droga , Endocanabinoides , Endotélio Vascular/citologia , Glicerídeos/metabolismo , Humanos , Proteínas dos Microfilamentos , Neurotransmissores/metabolismo , Fosfoproteínas/metabolismo , Fosforilação , Vasodilatadores/metabolismo , Vasodilatadores/farmacologia
17.
J Cereb Blood Flow Metab ; 20(7): 1056-65, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10908039

RESUMO

This study presents a quantitative comparison of the time courses and regional distribution of both constitutive HSC73 and inducible HSP72 mRNA expression and their respective encoded proteins between young (3-week-old) and adult (3-month-old) gerbil hippocampus after transient global ischemia. The constitutive expression of HSC73 mRNA and protein in the hippocampus of the young sham-operated gerbils was significantly higher than in the adults. The HSC73 mRNA expression after ischemia in the CA1 layer of young gerbils was greater than in adult gerbils. HSC73 immunoreactivity was not significantly changed after ischemia-reperfusion in adult hippocampus, whereas it decreased in young gerbils. Ischemia-reperfusion led to induction of HSP72 mRNA expression throughout the hippocampus of both young and adult gerbils. HSP72 mRNA induction was more intense and sustained in the CA1 subfield of young gerbils; this was associated with a marked induction of HSP72 proteins and neuronal survival. The transient expression of HSP72 mRNA in the CA1 layer of adult gerbils was not associated with a subsequent synthesis of HSP72 protein but was linked to neuronal loss. Expression of HSP72 mRNA was shifted to an earlier period of reflow in CA3 and dentate gyrus (DG) subfields of young animals. These findings suggest that the induction of both HSP72 mRNA and proteins in the CA1 pyramidal neurons of young gerbils, as well as the higher constitutive expression of HSC73, may partially contribute to higher neuronal resistance of young animals to transient cerebral ischemia.


Assuntos
Envelhecimento/metabolismo , Proteínas de Choque Térmico HSP70 , Proteínas de Choque Térmico/genética , Ataque Isquêmico Transitório/metabolismo , RNA Mensageiro/metabolismo , Animais , Regulação da Expressão Gênica , Gerbillinae , Proteínas de Choque Térmico HSC70 , Proteínas de Choque Térmico HSP72 , Proteínas de Choque Térmico/metabolismo , Imuno-Histoquímica , Hibridização In Situ , Ataque Isquêmico Transitório/genética , Ataque Isquêmico Transitório/patologia , Masculino , Neurônios/patologia , Neurônios/fisiologia
18.
Am J Physiol Cell Physiol ; 278(1): C144-53, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10644522

RESUMO

Brief "preconditioning" ischemia induces ischemic tolerance (IT) and protects the animal brain from subsequent otherwise lethal ischemia. Identification of the signaling steps most proximal to the development of the IT will allow induction of the resistance to ischemia shortly after the onset of stroke. Animal studies demonstrate a key role of tumor necrosis factor-alpha (TNF-alpha) in induction of IT. The sphingolipid ceramide is known as a second messenger in many of the multiple effects of TNF-alpha. We hypothesized that ceramide could mediate IT. We demonstrate that preconditioning of rat cortical neurons with mild hypoxia protects them from hypoxia and O(2)-glucose deprivation injury 24 h later (50% protection). TNF-alpha pretreatment could be substituted for hypoxic preconditioning (HP). HP was attenuated by TNF-alpha-neutralizing antibody. HP and TNF-alpha pretreatment cause a two- to threefold increase of intracellular ceramide levels, which coincides with the state of tolerance. Fumonisin B(1), an inhibitor of ceramide synthase, attenuated ceramide upregulation and HP. C-2 ceramide added to the cultures right before the hypoxic insult mimicked the effect of HP. Ceramide did not induce apoptosis. These results suggest that HP is mediated via ceramide synthesis triggered by TNF-alpha.


Assuntos
Isquemia Encefálica/metabolismo , Ceramidas/biossíntese , Precondicionamento Isquêmico , Neurônios/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Animais , Antígenos CD/metabolismo , Biomarcadores , Contagem de Células , Hipóxia Celular/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Neurônios/citologia , Oxigênio/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral , Esfingosina/análogos & derivados , Esfingosina/farmacologia , Regulação para Cima/fisiologia
19.
Plant Cell Rep ; 19(5): 459-463, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30754883

RESUMO

An efficient plant regeneration procedure has been established from hypocotyl explants of the common ice plant, Mesembryanthemum crystallinum L, a halophytic leaf succulent that exhibits a stress-induced switch from C3 photosynthesis to crassulacean acid metabolism (CAM). Somatic embryos were initiated and developed up to globular and heart stages in Murashige and Skoog (MS) media supplemented with 3% sucrose, 0.6% bacto-agar, 80 mM NaCl, 5 µM 2,4-D and 1 µM kinetin. High frequency regeneration occurred when somatic embryos were germinated on media that lacked 2,4-D. High cytokinin treatment suppressed normal growth of embryos and favored abnormal embryo proliferation. Without growth regulators, regenerated plants rooted on MS medium with 100% efficiency. Mature, regenerated plants were fertile and morphologically identical to seed-derived plants.

20.
Mol Med ; 6(12): 1028-41, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11474119

RESUMO

BACKGROUND: Tumor necrosis factor alpha (TNFalpha) plays a key role in pathogenesis of brain injury. However, TNFalpha exhibits no cytotoxicity in primary cultures of brain cells. This discrepancy suggests that other pathogenic stimuli that exist in the setting of brain injury precipitate TNFalpha cytotoxicity. The hypothesis was tested that reactive oxygen species (ROS), that are released early after brain injury, act synergistically with TNFalpha in causing cell death. MATERIALS AND METHODS: Cultured human and rat brain capillary endothelial cells (RBEC), and cortical astrocytes were treated with TNFalpha alone or together with different doses of H2O2, and apoptotic cell death and DNA fragmentation were measured by means of 3'-OH-terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and Hoechst fluorescence assay, respectively. The effect of H2O2 on TNFalpha-induced activation of nuclear factor kappa B (NF-kappaB) was measured by Western blots of cytoplasmic and nuclear extracts of RBEC using anti-inhibitor of NF-kappaB (IkappaB) and anti-p65 subunit of NF-kappaB antibodies. Nuclear translocation of NF-kappaB was investigated by immunofluorescent staining of RBEC with anti-p65 antibodies. RESULTS: TNFalpha alone had no cytotoxic effect in brain endothelial cells and astrocytes at concentrations up to 100 ng/ml. Co-treatment with 5-10 microM of H2O2 caused a two-fold increase in the number of apoptotic cells 24 hr later. Similar doses (1-3 microM) of H2O2 initiated early DNA fragmentation. H2O2 inhibited TNFalpha-induced accumulation of p65 in the nucleus, although it had no effect on degradation of the IkappaB in cytoplasm. Immunostaining confirmed that H2O2 inhibited p65 transport to the nucleus. CONCLUSIONS: Reactive oxygen species could act synergistically with TNFalpha in causing cytotoxicity via inhibition of a cytoprotective branch of TNFalpha signaling pathways, which starts with NF-kappaB activation.


Assuntos
Encéfalo/metabolismo , NF-kappa B/metabolismo , NF-kappa B/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Apoptose , Astrócitos/citologia , Astrócitos/metabolismo , Western Blotting , Capilares/metabolismo , Núcleo Celular/metabolismo , Células Cultivadas , Citosol/metabolismo , Fragmentação do DNA , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Ativação Enzimática , Humanos , Peróxido de Hidrogênio/farmacologia , Marcação In Situ das Extremidades Cortadas , Microscopia de Fluorescência , Ratos , Fatores de Tempo , Fator de Transcrição RelA
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