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1.
Eur Radiol ; 29(1): 77-84, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30027409

RESUMO

OBJECTIVES: As in-stent protrusion (ISP) during carotid artery stenting (CAS) may cause postoperative embolism, ISP detection is important. Intravascular ultrasound examination (IVUS) is useful for ISP detection because the blood vessel cross-section can be drawn as a tomogram from the lumen. Our objective was to clarify the occurrence of ISP during CAS using IVUS and relevant factors, and to report the usefulness of stent-in-stent placement when treating ISP. METHODS: In 142 consecutive patients (128 men, average age 71.7 years; 69 symptomatic) who underwent CAS using dual protection and the blood aspiration method, and subsequent IVUS after stent placement were included. The outcome of CAS, and the occurrence rate of ISP and related factors (plaque characteristics, stent design, intraoperative debris capture rate and postoperative diffusion-weighted imaging (DWI) positive rate) were examined. RESULTS: All CAS procedures were successful and no major adverse events (MAEs) were observed at 30 days. ISP was found in 12% (17/142), and stent-in-stent placement was performed in all cases. Vulnerable plaques were observed in 12 of 17 ISP cases (71%). A closed stent was used in 13 of 17 ISP cases (71%). The intraoperative debris capture rate was 100%, and no neurological symptoms were observed in any patients. A significant increase in ISP susceptibility was related to vulnerable plaques and the intraoperative debris capture rate. CONCLUSIONS: Vulnerable plaques and debris capture were significantly correlated with ISP occurrence. In all ISP cases, stent-in-stent placement was performed and good results were obtained. KEY POINTS: • ISP detection during CAS using IVUS is important. • ISP-positive patients were correlated with NASCET ≥ 80%, vulnerable plaques and stent length. • Adequate additional treatment of stent in stenting under reliable protection against ISP-positive patients achieved low perioperative complications.


Assuntos
Artéria Carótida Primitiva/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Placa Aterosclerótica/cirurgia , Stents/efeitos adversos , Ultrassonografia de Intervenção/métodos , Idoso , Artéria Carótida Primitiva/cirurgia , Estenose das Carótidas/diagnóstico , Estenose das Carótidas/etiologia , Feminino , Humanos , Período Intraoperatório , Angiografia por Ressonância Magnética , Masculino , Placa Aterosclerótica/complicações , Placa Aterosclerótica/diagnóstico , Falha de Prótese , Resultado do Tratamento
2.
Am J Transplant ; 15(5): 1192-204, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25731734

RESUMO

We have reported that B6.CCR5(-/-) mice reject renal allografts with high serum donor-specific antibody (DSA) titers and marked C4d deposition in grafts, features consistent with antibody-mediated rejection (AMR). B6.huCD20/CCR5(-/-) mice, where human CD20 expression is restricted to B cells, rejected A/J renal allografts by day 26 posttransplant with DSA first detected in serum on day 5 posttransplant and increased thereafter. Recipient treatment with anti-huCD20 mAb prior to the transplant and weekly up to 7 weeks posttransplant promoted long-term allograft survival (>100 days) with low DSA titers. To investigate the effect of B cell depletion at the time serum DSA was first detected, recipients were treated with anti-huCD20 mAb on days 5, 8, and 12 posttransplant. This regimen significantly reduced DSA titers and graft inflammation on day 15 posttransplant and prolonged allograft survival >60 days. However, DSA returned to the titers observed in control treated recipients by day 30 posttransplant and histological analyses on day 60 posttransplant indicated severe interstitial fibrosis. These results indicate that anti-huCD20 mAb had the greatest effect as a prophylactic treatment and that the distinct kinetics of DSA responses accounts for acute renal allograft failure versus the development of fibrosis.


Assuntos
Anticorpos/imunologia , Antígenos CD20/química , Rejeição de Enxerto/prevenção & controle , Transplante de Rim , Insuficiência Renal/imunologia , Insuficiência Renal/cirurgia , Aloenxertos , Animais , Formação de Anticorpos/imunologia , Creatinina/sangue , Modelos Animais de Doenças , Fibrose/fisiopatologia , Citometria de Fluxo , Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microscopia de Fluorescência , Receptores CCR5/genética , Fatores de Tempo , Transplante Homólogo
3.
JAR Life ; 12: 56-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37519417

RESUMO

Background: Exercise, education, and social engagement are critical interventions for older adults for a healthy life expectancy and to improve their physical function. Objective: To conduct a combined exercise and education (CEE) program for improved social engagement and physical function of older adults. Design: Based on a short-term program we conducted in our previous study, in this study, the program was conducted for half the number of participants of the earlier study but for a longer duration. Setting: A community of older adults in Ami, Japan, was the setting of the study. Participants: 23 healthy older adults >65 years living in the community were the participants in the study. Interventions: Five 80-minute sessions conducted once in two weeks comprised 60-min exercise instruction and 20-min educational lectures per session on health. We examined the improvement in physical and social engagement before and after participation. Physical function and health-related questionnaire data were collected before and after the program. Results: Data analysis from 15 participants showed improved physical performance but no effect on social engagement. Conclusions: A higher program frequency, rather than program duration, may be vital to improving exercise performance and social engagement and maximizing the effects of high group cohesion in small groups. Further studies are needed to develop more effective interventions to extend healthy life expectancy.

4.
Am J Transplant ; 11(5): 923-35, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21466654

RESUMO

Alloreactive memory T cells are present in virtually all transplant recipients due to prior sensitization or heterologous immunity and mediate injury undermining graft outcome. In mouse models, endogenous memory CD8 T cells infiltrate MHC-mismatched cardiac allografts and produce IFN-γ in response to donor class I MHC within 24 h posttransplant. The current studies analyzed the efficacy of anti-LFA-1 mAb to inhibit early CD8 T cell cardiac allograft infiltration and activation. Anti-LFA-1 mAb given to C57BL/6 6 (H-2(b)) recipients of A/J (H-2(a)) heart grafts on days -1 and 0 completely inhibited CD8 T cell allograft infiltration, markedly decreased neutrophil infiltration and significantly reduced intragraft expression levels of IFN-γ-induced genes. Donor-specific T cells producing IFN-γ were at low/undetectable numbers in spleens of anti-LFA-1 mAb treated recipients until day 21. These effects combined to promote substantial prolongation (from day 8 to 27) in allograft survival. Delaying anti-LFA-1 mAb treatment until days 3 and 4 posttransplant did not inhibit early memory CD8 T cell infiltration and proliferation within the allograft. These data indicate that peritransplant anti-LFA-1 mAb inhibits early donor-reactive memory CD8 T cell allograft infiltration and inflammation suggesting an effective strategy to attenuate the negative effects of heterologous immunity in transplant recipients.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Linfócitos T CD8-Positivos/imunologia , Transplante de Coração/métodos , Antígeno-1 Associado à Função Linfocitária/metabolismo , Linfócitos T/citologia , Animais , Anticorpos Monoclonais/metabolismo , Linfócitos T CD8-Positivos/citologia , Citometria de Fluxo/métodos , Imuno-Histoquímica/métodos , Memória Imunológica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Homólogo/métodos
5.
Am J Transplant ; 10(1): 59-68, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19958333

RESUMO

The acute phase cytokines IL-1beta, IL-6 and TNFalpha are produced early during inflammatory processes, including ischemia-reperfusion. The appearance and role of these cytokines in the early inflammation following reperfusion of grafts remain poorly defined. This study investigated the role of TNFalpha in the induction of early leukocyte infiltration into vascularized heart allografts. TNFalpha and IL-6 mRNA levels reached an initial peak 3 h posttransplant and a second peak at 9-12 h with equivalent levels in iso- and allografts. A single dose of anti-TNFalpha mAb given at reperfusion decreased neutrophil and macrophage chemoattractant levels and early neutrophil, macrophage and memory CD8 T-cell infiltration into allografts. Anti-TNFalpha mAb also extended graft survival from 8.6+/-0.6 days to 14.1+/-0.8 days. When assessed on day 7 posttransplant, the number of donor-reactive CD8 T cells producing IFN-gamma in the spleen was reduced almost 70% in recipients treated with anti-TNFalpha mAb. Whereas anti-CD154 mAb prolonged survival to day 21, administration of anti-TNFalpha and anti-CD154 mAb delayed rejection to day 32 and resulted in long-term (>80 days) survival of 40% of the heart allografts. These data implicate TNFalpha as an important mediator of early inflammatory events in allografts that undermine graft survival.


Assuntos
Quimiocinas/biossíntese , Transplante de Coração/imunologia , Transplante de Coração/patologia , Leucócitos/imunologia , Leucócitos/patologia , Fator de Necrose Tumoral alfa/imunologia , Doença Aguda , Animais , Anticorpos Monoclonais/administração & dosagem , Quimiocinas/genética , Rejeição de Enxerto/genética , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/patologia , Sobrevivência de Enxerto/imunologia , Transplante de Coração/efeitos adversos , Interleucina-1beta/biossíntese , Interleucina-1beta/genética , Interleucina-6/biossíntese , Interleucina-6/genética , Masculino , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Neutrófilos/imunologia , Neutrófilos/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/imunologia , Traumatismo por Reperfusão/patologia , Transplante Homólogo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/genética
6.
Am J Transplant ; 9(10): 2251-61, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19656127

RESUMO

The effector CD4 T-cell response in wild-type C57BL/6 recipients of single class II MHC-disparate B6.H-2(bm12) cardiac allografts is restricted by CD4(+)CD25(+) regulatory T cells (Tregs) resulting in long-term allograft survival. To investigate the role chemokine receptors might play in Treg function, this study tested the requirement for CCR5 on Tregs to suppress the alloimmune response in C57BL/6 recipients of B6.H-2(bm12) cardiac allografts. In contrast to the long-term survival of B6.H-2(bm12) allografts in wild-type recipients (>100 days), the allografts were acutely rejected within 25 days in CCR5(-/-) recipients with intense infiltration of CD4 T cells. Numbers and duration of donor-reactive CD4 T cells producing IFN-gamma and IL-4 were markedly increased in spleens of B6.CCR5(-/-) versus wild-type recipients. Wild-type and B6.CCR5(-/-) mice had equivalent numbers of splenic FoxP3(+) Tregs before and following transplantation, and these Tregs were equivalently suppressive in vitro. However, diminished numbers of FoxP3(+) Tregs infiltrated B6.H-2(bm12) allografts in B6.CCR5(-/-) recipients. Adoptive transfer of wild-type, but not CCR5-deficient, CD4(+)CD25(+) Tregs to CCR5(-/-) recipients restored long-term survival of B6.H-2(bm12) cardiac grafts. Collectively, these results indicate that CCR5 expression is required for the regulatory functions of Tregs that restrict alloreactive CD4 T-cell responses to single class II MHC-mismatched cardiac allografts.


Assuntos
Transplante de Coração/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Receptores CCR5/fisiologia , Linfócitos T Reguladores/fisiologia , Animais , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptores CCR5/genética
7.
Science ; 200(4341): 556-9, 1978 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-644318

RESUMO

When added to mouse neuroblastoma cultures, the potent tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate (TPA) inhibits spontaneous neurite formation as well as that induced in response to serum deprivation, prostaglandin E1, 5-bromo-2'-deoxyuridine, and papaverine. Other tumor-promoting macrocyclic plant diterpenes also inhibit neurite formation, whereas nonpromoting diterpenes do not. Inhibition by TPA was reversible and was unrelated to toxicity.


Assuntos
Neurônios/citologia , Forbóis/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Bromodesoxiuridina/antagonistas & inibidores , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Diterpenos/farmacologia , Relação Dose-Resposta a Droga , Neuroblastoma/patologia , Papaverina/antagonistas & inibidores , Prostaglandinas E/antagonistas & inibidores
8.
J Natl Cancer Inst ; 68(2): 299-303, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6950162

RESUMO

The strong correlation between tumor-promoting activity and the capacity to inhibit nerve growth factor-induced neurite outgrowth for a number of compounds prompted studies on the suspected bladder tumor promoters saccharin and cyclamate. These artificial sweeteners reversibly inhibited neurite outgrowth and binding of [125I]nerve growth factor in embryonic chick sensory ganglia cells. Curves showing the dose-dependent inhibition of response and the dose-dependent inhibition of binding to high affinity sites were closely parallel. The inhibition appeared to be due to a reduction in the affinity rather than to a change in the number of binding sites, as indicated by the extent of reduction in the association rate. These results suggest that alteration of cellular differentiation by tumor promoters may result from interactions with receptor systems that regulate specialized cell functions.


Assuntos
Ciclamatos/farmacologia , Fatores de Crescimento Neural/metabolismo , Sacarina/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Relação Dose-Resposta a Droga
9.
Cancer Res ; 38(11 Pt 1): 3886-93, 1978 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-698941

RESUMO

The tumor-promoting plant diterpene 12-O-tetradecanoyl-phorbol-13-acetate (TPA) inhibits nerve growth factor (NGF)-provoked neurite outgrowth in cultured embryonic chick sensory and sympathetic ganglia. Other plant diterpenes that are tumor promoters on the mouse skin carcinogenesis system also inhibit ganglia response to NGF, but structurally related nonpromoting compounds are inactive. There is no evidence that the inhibitory effect of TPA is due to cytotoxicity. In fact, it appears that TPA can enhance the survival of neuronal and nonneuronal cells in culture. Although neurite outgrowth is prevented, established neurites do not retract in the presence of TPA. After 24 hr, ganglia can slowly overcome the block, even in the presence of fresh TPA; thus, inhibition is transient. The concentration of NGF that does induce a half-maximal neurite outgrowth response in sensory ganglia is approximately 0.6 X 10(-11) M. The antagonism of NGF by TPA is dose dependent and apparently noncompetitive. TPA concentrations that extensively inhibit neurite outgrowth do not affect the amount of 125I-labeled NGF bound to specific sites on dissociated dorsal root ganglion cells, which supports the contention that TPA acts at a stage beyond the initial interaction of the factor with its receptive site.


Assuntos
Gânglios/efeitos dos fármacos , Fatores de Crescimento Neural/antagonistas & inibidores , Forbóis/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Animais , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Relação Dose-Resposta a Droga , Gânglios/embriologia , Gânglios Autônomos/efeitos dos fármacos , Gânglios Espinais/efeitos dos fármacos , Cinética , Fatores de Crescimento Neural/administração & dosagem , Ésteres de Forbol/farmacologia , Acetato de Tetradecanoilforbol/administração & dosagem
10.
Cancer Res ; 42(2): 429-32, 1982 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7055797

RESUMO

The suspected bladder tumor promoters saccharin and cyclamate reversibly inhibited nerve growth factor-induced neurite outgrowth in embryonic chick sensory ganglia, and active concentrations of these artificial sweeteners inhibited binding of 125I-labeled mouse submaxillary gland nerve growth factor as well. The skin tumor promoter phenol also reversibly inhibited neurite outgrowth, while comparable concentrations of the nonpromoting but structurally related compounds benzene and fluorobenzene did not. However, in contrast to findings with saccharin and cyclamate, phenol had little, if any, effect on binding of radioactive nerve growth factor.


Assuntos
Carcinógenos/farmacologia , Ciclamatos/farmacologia , Fatores de Crescimento Neural/metabolismo , Nervos Periféricos/efeitos dos fármacos , Fenóis/farmacologia , Sacarina/farmacologia , Animais , Axônios/efeitos dos fármacos , Embrião de Galinha , Técnicas de Cultura , Relação Dose-Resposta a Droga , Gânglios/efeitos dos fármacos , Gânglios/embriologia , Gânglios/metabolismo , Camundongos , Fenol , Glândula Submandibular/inervação
11.
Cancer Res ; 43(9): 4119-25, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6307504

RESUMO

The mouse skin tumor promoter phorbol-12,13-dibutyrate (PDBU) reversibly enhanced neurite outgrowth in SH-SY5Y human neuroblastoma cells, whether serum was present or absent. The half-maximum response in serum occurred at 10 nM. The binding of [20-3H]phorbol-12,13-dibutyrate [( 3H]PDBU) was studied. Five mouse skin tumor promoters, which included teleocidin, mezerein, and three structural congeners of phorbol, enhanced neurite outgrowth and inhibited binding of [3H]PDBU, but two nonpromoting phorbol congeners did neither. Saccharin and cyclamate, promoters in rat bladder, did not inhibit [3H]PDBU binding. Binding of 10 nM [3H]PDBU at 37 degrees was maximal within 5 min and stable for at least 5 hr. Down modulation of binding was not detected. Following binding at 37 degrees, the dissociation rate in excess PDBU was biphasic, whether measured at 37 degrees or at 4 degrees. The Scatchard curve was also consistent with two types of sites, about 2.5 X 10(5) sites/cell with Kd = 8.5 nM and 1.2 X 10(6) sites with Kd = 125 nM. Negative cooperativity was not observed. In short-term assays, nerve growth factor (NGF) did not alter [3H]PDBU binding, and phorbol ester promoters did not alter 125I-NGF binding. Furthermore, [3H]PDBU binding was unaltered following growth of cells for 1 week in PDBU or NGF, conditions under which neurite outgrowth was continuously enhanced, and other phenotypic expressions of differentiation are known to be increased. Specific [3H]PDBU binding sites were present in five neuroblastoma cell lines, two of which are responsive and three unresponsive by neurite outgrowth to promoters and NGF, suggesting the possibility of a common lesion in distal steps in the unresponsive lines.


Assuntos
Axônios/fisiologia , Proteínas de Caenorhabditis elegans , Carcinógenos/toxicidade , Neuroblastoma/fisiopatologia , Ésteres de Forbol/metabolismo , Ésteres de Forbol/toxicidade , Forbóis/metabolismo , Forbóis/toxicidade , Proteína Quinase C , Receptores de Superfície Celular/metabolismo , Receptores de Droga , Axônios/efeitos dos fármacos , Axônios/ultraestrutura , Proteínas de Transporte , Linhagem Celular , Humanos , Cinética , Dibutirato de 12,13-Forbol
12.
Cancer Res ; 42(12): 5067-73, 1982 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-7139611

RESUMO

The effect of phorbol ester tumor promoters on neurite outgrowth was studied in cultured human neuroblastoma cell lines and in cultured embryonic chick and neonatal rat sympathetic ganglia. Promoters inhibited nerve growth factor (NGF)-stimulated neurite outgrowth in sympathetic ganglia while nonpromoting structural congeners did not, in keeping with previous results in embryonic sensory ganglia. In contradistinction, promoters reversibly enhanced neurite outgrowth in malignant SH-SY5Y neuroblastoma cells, whereas nonpromoting congeners were inactive. The potent promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) reversibly increased the proportion of SH-SY5Y cells with neurites and the average length of neurites; the effects of the combination of TPA and NGF were greater than that of either compound alone. The half-maximum response to TPA was at about 2 ng/ml (3 nM). The neurites were thinner, straighter, and less branched and showed more swellings resembling beads or varicosities in comparison with NGF-induced neurites. TPA transiently inhibited the cellular growth rate between Days 2 and 4. Thereafter, the rate was the same as in untreated cultures. The transient inhibition was due to causes other than degradation of TPA since fresh TPA was added. The effect of TPA on neurite outgrowth was not transient and was independent of effects on growth. TPA also enhanced neurite outgrowth in another NGF responsive line, LA-N-5, but not in two unresponsive lines, CHP-100 and CHP-134.


Assuntos
Axônios/fisiologia , Fatores de Crescimento Neural/farmacologia , Neuroblastoma/fisiopatologia , Forbóis/farmacologia , Acetato de Tetradecanoilforbol/farmacologia , Animais , Axônios/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Linhagem Celular , Embrião de Galinha , Gânglios Simpáticos/efeitos dos fármacos , Gânglios Simpáticos/fisiologia , Humanos
13.
Diabetes ; 38(6): 730-6, 1989 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2656342

RESUMO

Peripheral neuropathy is a common and well-studied complication of diabetes mellitus, but the possibility that central neuropathy is also present has received scant attention. Based on recent evidence showing that insulin has a direct effect on axon formation and neuronal survival in vitro, it was predicted that functional neuropathy would be present in the spinal cord of diabetic animals. Although structural lesions are encountered in the spinal cord of diabetic patients at autopsy, the functional corollaries have essentially remained unstudied. We used a new procedure to study evoked spinal cord potentials in the rat, which revealed a significant retardation in conduction velocity in streptozocin (STZ)-induced diabetic animals. This retardation was not due to a toxic effect of STZ on the involved spinal cord sensory pathways, because insulin infusion prevented the development of spinal cord neuropathy. The kinetics and magnitude of decline in conduction velocity were similar in the spinal cord, saphenous nerve, and common peroneal nerve during the first 2 wk, suggesting that a common mechanism was involved. After 10 wk, a spontaneous improvement in function was observed in the spinal cord and common peroneal nerve but not in the saphenous nerve. Our results support the hypothesis that central nervous system dysfunction can occur along with peripheral sensory neuropathy in diabetes.


Assuntos
Diabetes Mellitus Experimental/fisiopatologia , Neuropatias Diabéticas/fisiopatologia , Medula Espinal/fisiopatologia , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Potenciais Evocados , Insulina/uso terapêutico , Condução Nervosa , Nervos Periféricos/fisiologia , Ratos , Ratos Endogâmicos
14.
Pharmacol Ther ; 62(1-2): 125-44, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7991639

RESUMO

Prolonged denervation results in atrophy of target organs and increased risk of permanent paralysis. A better understanding of the mechanism responsible for nerve regeneration may one day lead to improved rates of nerve regeneration and diminished risk of loss of function. Neurobiologists have known for decades that soluble neurotrophic activity is present in nerves and nerve targets. Until recently, the soluble molecules that regulate the rate of nerve regeneration have eluded identification. Insulin-like growth factor (IGF) gene expression is correlated with synapse formation during development and regeneration. IGFs are now identified as the first soluble nerve- and muscle-derived neurotrophic factors found to regulate the rate of peripheral nerve regeneration. The roles of IGFs and other neurotrophic factors in peripheral nerve regeneration, motor nerve terminal sprouting and synapse formation are reviewed.


Assuntos
Fator de Crescimento Insulin-Like II/fisiologia , Fator de Crescimento Insulin-Like I/fisiologia , Regeneração Nervosa , Nervos Periféricos/fisiologia , Animais , Axônios/efeitos dos fármacos , Axônios/fisiologia , Regulação da Expressão Gênica/genética , Humanos , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Regeneração Nervosa/genética , Junção Neuromuscular/genética , Nervos Periféricos/efeitos dos fármacos , Ratos , Sinapses/efeitos dos fármacos , Sinapses/fisiologia
15.
J Mol Biol ; 192(4): 737-52, 1986 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-2438416

RESUMO

We have characterized the single-copy rat gene encoding the protein precursor of insulin-like growth factor II (pre-pro-rIGF-II) that is located downstream from and in the same transcriptional orientation as the homologous insulin II gene (5'-insulin-IGF-II-3'). This gene consists of at least three coding exons and utilizes two promoters that generate alternate 5' non-coding exons. Multiple transcripts from both promoters appear primarily in fetal or neonatal tissues (in all of the developmental stages and tissues that we have examined), but they are extremely rare or undetectable in adult tissues, with the exception of the brain and the spinal cord. These transcripts, which exhibit characteristic developmental profiles in various tissues, differ both in the presence of one of the alternate 5' non-coding exons and in the length of their fourth exon. The possible occurrence of differential splicing or differential polyadenylation (or both) in this region is discussed.


Assuntos
Genes , Fator de Crescimento Insulin-Like II/genética , Regiões Promotoras Genéticas , Somatomedinas/genética , Animais , Sequência de Bases , Linhagem Celular , Células Cultivadas , DNA/genética , Humanos , Camundongos , Hibridização de Ácido Nucleico , RNA/genética , Ratos , Transcrição Gênica
16.
Genes Brain Behav ; 14(3): 301-9, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25704122

RESUMO

DNA methylation is one of the essential factors in the control of gene expression. Alteration of the DNA methylation pattern has been linked to various neurological, behavioral and neurocognitive dysfunctions. Recent studies have pointed out the importance of epigenetics in brain development and functions including learning and memory. Nutrients related to one-carbon metabolism are known to play important roles in the maintenance of genomic DNA methylation. Previous studies have shown that the long-term administration of a diet lacking essential one-carbon nutrients such as methionine, choline and folic acid (methyl donors) caused global DNA hypermethylation in the brain. Therefore, the long-term feeding of a methyl-donor-deficient diet may cause abnormal brain development including learning and memory. To confirm this hypothesis, 3-week-old mice were maintained on a folate-, methionine- and choline-deficient (FMCD) or control (CON) diet for 3 weeks. We found that the methyl-donor deficiency impaired both novel object recognition and fear extinction after 3 weeks of treatment. The FMCD group showed spontaneous recovery of fear that differed from that in CON. In addition, we found decreased Gria1 gene expression and specific CpG hypermethylation of the Gria1 promoter region in the FMCD hippocampus. Our data suggest that a chronic dietary lack of methyl donors in the developmental period affects learning, memory and gene expressions in the hippocampus.


Assuntos
Deficiência de Colina/genética , Deficiência de Colina/psicologia , Deficiência de Ácido Fólico/genética , Deficiência de Ácido Fólico/psicologia , Hipocampo/fisiologia , Memória/fisiologia , Metionina/deficiência , Fatores Etários , Animais , Colina/administração & dosagem , Deficiência de Colina/sangue , Metilação de DNA , Dieta , Epigênese Genética , Ácido Fólico/administração & dosagem , Deficiência de Ácido Fólico/sangue , Hipocampo/crescimento & desenvolvimento , Hipocampo/metabolismo , Homocisteína/sangue , Metionina/administração & dosagem , Metionina/sangue , Camundongos , Camundongos Endogâmicos C57BL , Modelos Animais , Necessidades Nutricionais , Regiões Promotoras Genéticas , Receptores de AMPA/biossíntese , Receptores de AMPA/genética , Receptores de Glutamato/biossíntese , Receptores de Glutamato/genética
17.
Endocrinology ; 142(1): 213-20, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11145584

RESUMO

Peripheral administration of human insulin-like growth factor (hIGF) results in both uptake of hIGF into the cerebrospinal fluid (CSF) and amelioration of brain injury. We tested the hypotheses that IGF uptake into CSF is independent of IGF receptors and IGF-binding proteins (IGFBP). Adult rats were injected sc with various concentrations of hIGF-I or structural analogs, and serum and CSF were withdrawn for assay 90 min later. An enzyme-linked immunoassay was used that detected immunoreactive hIGF-I and its analogs, but not rat IGF-I, IGF-II, or insulin. Plasma hIGF-I levels increased linearly (r = 0.97) with hIGF-I dose between 25-300 microgram/rat. By contrast, uptake into CSF reached saturation above 100 microgram, suggesting carrier-mediated uptake. hIGF-II reduced the uptake of hIGF-I into CSF (P < 0.02). Des(1-3)hIGF-I is a hIGF-I analog missing the N-terminal tripeptide, resulting in greatly reduced affinity for IGFBP-1, -3, -4, and -5. Nevertheless, des(1-3)hIGF-I was taken up into CSF. [Leu(24)]hIGF-I and [Leu(60)]hIGF-I have 20- to 85-fold reduced affinity for the type I IGF receptor, yet both were taken up into CSF in amounts similar to hIGF-I. In addition, hIGF-I and des(1-3)hIGF-I were taken up into CSF, although binding to the type II receptor is extremely weak. These data suggest that uptake of circulating IGF-I into CSF is independent of the type I or II IGF receptors as well as IGF sequestration to IGFBP-1, -3, -4, or -5.


Assuntos
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo , Fator de Crescimento Insulin-Like II/farmacocinética , Fator de Crescimento Insulin-Like I/farmacocinética , Receptor IGF Tipo 1/metabolismo , Receptor IGF Tipo 2/metabolismo , Animais , Ensaio de Imunoadsorção Enzimática , Humanos , Fator de Crescimento Insulin-Like I/análogos & derivados , Fator de Crescimento Insulin-Like I/líquido cefalorraquidiano , Fator de Crescimento Insulin-Like II/líquido cefalorraquidiano , Cinética , Masculino , Ratos , Ratos Sprague-Dawley , Análise de Regressão
18.
Endocrinology ; 143(4): 1213-7, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11897675

RESUMO

The metabolic abnormalities underlying the cause of diabetic neuropathy have been the subject of much debate. Lipoprotein lipase (LPL) is a 56-kDa enzyme produced by several tissues in the body and has recently been shown in vitro to be expressed in cultured Schwann cells, where it is important in phospholipid synthesis. This suggests a role for LPL in myelin biosynthesis in the peripheral nervous system. The aim of this study was to determine if acute streptozotocin (STZ)-induced diabetes reduces the expression and regulation of sciatic nerve LPL in vivo. Adult Sprague Dawley rats were rendered diabetic via an sc injection of STZ. A decrease in sciatic nerve LPL activity was observed in the STZ-treated rats after just 2 d of diabetes and remained significantly reduced for at least 35 d. The decrease in LPL activity coincided temporally with a drop in motor nerve conduction velocity. Treatment with insulin for 4 d showed a normalization of sciatic nerve LPL activity. These results show that STZ-induced diabetes causes a decrease in LPL activity in the sciatic nerve that, as in other tissues, is reversible with insulin treatment. These data may suggest a role for LPL in the pathophysiology of diabetic neuropathy.


Assuntos
Diabetes Mellitus Experimental/enzimologia , Hipoglicemiantes/farmacologia , Insulina/farmacologia , Lipase Lipoproteica/metabolismo , Nervo Isquiático/enzimologia , Animais , Anticoagulantes/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Heparina/farmacologia , Masculino , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/fisiologia , Condução Nervosa/efeitos dos fármacos , RNA Mensageiro/biossíntese , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/efeitos dos fármacos
19.
Neuroscience ; 54(3): 791-7, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8332262

RESUMO

A slow rate of nerve regeneration conspires together with atrophy and degeneration of denervated organs to increase the risk of permanent disability following injury to the mammalian peripheral nervous system. Therefore, it is of both practical and theoretical interest to identify those endogenous factors that determine the spontaneous velocity of nerve regeneration, and to discover exogenous factors which hold promise for augmenting the rate. We report that locally infused insulin-like growth factor II significantly increases the speed of sensory axon regeneration in rat sciatic nerves. It appeared that 1 microgram/ml insulin-like growth factor II acted through insulin-like growth factor receptors, because a comparable concentration of insulin had little effect. Furthermore, there was a sustained reduction in regeneration rate when an anti-insulin-like growth factor II antiserum was continuously infused near a window in the epineurium located just below a site of nerve crush, indicating that the spontaneous regeneration rate was continuously dependent on endogenous insulin-like growth factor activity. These results show that exogenously administered insulin-like growth factor II can increase the rate of peripheral nerve regeneration, and that the endogenous insulin-like growth factors in nerves are required to maintain the normal rate of regeneration. These in vivo data complement previous observations showing that insulin-like growth factors can increase neurite outgrowth in cultured neurons, and that insulin-like growth factor II gene expression is correlated with synapse development. They further support the hypothesis that insulin-like growth factors play a role in nerve regeneration.


Assuntos
Fator de Crescimento Insulin-Like II/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Nervo Isquiático/efeitos dos fármacos , Animais , Humanos , Insulina/farmacologia , Fator de Crescimento Insulin-Like II/imunologia , Masculino , Compressão Nervosa , Neurônios Aferentes/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/farmacologia , Nervo Isquiático/citologia , Estimulação Química
20.
Br J Pharmacol ; 131(3): 610-6, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11015314

RESUMO

The effects of two sigma (sigma) binding site ligands, (+)-pentazocine and 1,3-di-o-tolylguanidine (DTG), on bladder functions were examined in rats. Cystometry using urethane-anaesthetized rats showed that (+)-pentazocine (1 - 5 mg kg(-1), i.v.) and DTG (1 - 5 mg kg(-1), i.v.) prolonged micturition intervals, indicating increased bladder capacity and raised the threshold pressure. The effects of (+)-pentazocine (2 mg kg(-1), i.v. ) on micturition were not influenced by naloxone (0.5 mg kg(-1), i.v. ), which antagonized similar effects of morphine (2 mg kg(-1), i.v.). When administered intracerebroventricularly (i.c.v.), DTG (1 microg) and (+)-pentazocine (30 microg) prolonged micturition intervals with increased threshold pressure on the cystometrogram. In isolated bladder detrusor strips of rats, (+)-pentazocine (3 microM) and DTG (1 microM) did not affect contractile responses to electrical field stimulation. A higher concentration of DTG (3 microM) slightly suppressed the response induced by 30 Hz stimulation. The effects of (+)-pentazocine and DTG on micturition were abolished by pre-treatment with pertussis toxin (PTX, 1 microg, i.c.v.). These results indicate that typical sigma ligands, such as (+)-pentazocine and DTG, increase bladder capacity in anaesthetized rats. Moreover, the mechanism by which sigma ligands change the urinary storage properties in rats may involve pathways in which the function of Gi/o proteins is necessary.


Assuntos
Guanidinas/farmacologia , Pentazocina/farmacologia , Receptores sigma/metabolismo , Bexiga Urinária/metabolismo , Anestesia , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Estimulação Elétrica , Ligantes , Masculino , Contração Muscular/efeitos dos fármacos , Antagonistas de Entorpecentes/farmacologia , Antagonistas de Entorpecentes/uso terapêutico , Toxina Pertussis , Ratos , Ratos Wistar , Síncope/induzido quimicamente , Síncope/tratamento farmacológico , Bexiga Urinária/efeitos dos fármacos , Fatores de Virulência de Bordetella/farmacologia
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