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3.
Br J Dermatol ; 167(1): 198-201, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22428864

RESUMO

BACKGROUND: Solar urticaria (SU) is a photodermatosis that is thought to be caused through the effects of mast cell mediators released because of an altered chromophore, possibly a photoallergen recognized by IgE. Phototherapy for SU to induce a tolerant state appears to be most effective, but is often time consuming and provides only short-lived remission. Ultraviolet (UV) A rush hardening has been successful and less time consuming in serum factor-negative patients with SU. However, the mechanism of action and long-lasting effects of UVA rush hardening therapy remain unclear. OBJECTIVES: We aimed to evaluate whether UVA rush hardening exhibits long-lasting therapeutic effects in serum factor-positive patients with SU and to examine the action mechanism of tolerance. METHODS: Two serum factor-positive patients with SU were exposed to multiple UVA irradiations at 1-h intervals per day for 2 or 3 days. Intradermal injection of their in vitro-irradiated autologous serum or compound 48/80 and a prick test for histamine were performed before and after UVA rush hardening. RESULTS: The two serum factor-positive patients with SU benefited greatly from UVA rush hardening, as documented by a marked increase in minimal wealing dose, and remained symptom free without using sunscreen in their daily life. Intradermal injection of in vitro-irradiated autologous serum induced wealing before hardening, but not in tolerized skin after hardening. The responses to compound 48/80 and histamine were unaltered. CONCLUSIONS: UVA rush hardening is an effective and long-lasting treatment even in serum factor-positive patients with SU. The mechanism of tolerance may involve continued blockade of photoallergen binding to IgE on mast cells, rather than depletion of mast cell mediators or histamine tachyphylaxis.


Assuntos
Transtornos de Fotossensibilidade/radioterapia , Luz Solar/efeitos adversos , Terapia Ultravioleta/métodos , Urticária/radioterapia , Adulto , Eritema/etiologia , Eritema/radioterapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Urticária/etiologia
4.
Acta Gastroenterol Belg ; 85(1): 7-14, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35304988

RESUMO

Background and study aims: This study evaluated the longterm outcomes of mainly endoscopic hemostatic therapy for gastrointestinal variceal bleeding and of the transition of hemostatic therapy. Patients and methods: Among 1,163 patients treated for gastrointestinal varices between April 2006 and June 2020, a total of 125 patients who underwent emergency hemostatic therapy were enrolled. Survival rates and secondary evaluation points were analyzed. Additionally, patients were classified into two groups: the previous and latter term. Patients' background, therapeutic method, and treatment results were compared between the groups. Results: 94.4% had cirrhosis. The average Child-Pugh score was 8.90. Successful primary hemostasis rate was 98.4%, and 5.6% died within 2 weeks, all with a Child-Pugh score ≥9. The respective 1- and 5-year survival rates for Child-Pugh grade A/B were 81.3% and 55.4%, while those for Child-Pugh grade C were 58.1% and 17.8%. Child-Pugh grade C or hepatocellular carcinoma was significantly associated with poor prognosis. In total, 21.6% experienced variceal re-bleeding; 62.9% of these cases were triggered by continued alcohol consumption. There was no significant difference in survival between patients with and without variceal re-bleeding and in post-treatment survival between the previous and latter terms. In the latter term, the number of cases caused by continued alcohol consumption significantly increased. Conclusions: Multidisciplinary treatment and continuation of proper management after hemostatic therapy for variceal bleeding are crucial. Continued alcohol consumption leads to variceal bleeding and re-bleeding; its proper management, including alcohol abstinence, is one of the major challenges left in the post-directacting antivirals era.


Assuntos
Varizes Esofágicas e Gástricas , Hemostáticos , Hepatite C Crônica , Neoplasias Hepáticas , Varizes , Antivirais , Varizes Esofágicas e Gástricas/complicações , Varizes Esofágicas e Gástricas/terapia , Hemorragia Gastrointestinal/tratamento farmacológico , Hemorragia Gastrointestinal/etiologia , Hemostasia , Hemostáticos/uso terapêutico , Hepatite C Crônica/complicações , Humanos
6.
J Eur Acad Dermatol Venereol ; 22(2): 168-73, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18211409

RESUMO

BACKGROUND: Mondor's disease (MD) is considered an inflammatory condition of superficial vasculitis that develops mainly in the anterolateral thoracoabdominal wall. The pathogenesis of the disease has been controversial, however, because of the lack of histopathologic methods for differentiating between the small vein and the lymphatic vessel. AIM: To objectively examine the origin of vascular lesions in MD, we investigated the endothelial cells of their blood and lymphatic vessels. METHODS: Immunohistochemical examinations were carried out on specimens involving vascular lesions from 16 patients with MD, using antibodies against von Willebrand factor and human lymphatic vessel endothelial hyaluronan receptor-1, which specifically discriminate between lymphatic and blood vessels. RESULTS: The histopathologic findings clearly showed thrombophlebitis in 14 patients, a lesion originating in the lymphatic vessel in one patient, and sclerosis that consisted of the artery together with veins in another. CONCLUSION: This study suggests that almost all cases of MD are due to thrombophlebitis, with a small minority due to lymphangitis or other conditions. We believe this study will contribute to the better recognition of the factual changes in the condition designated MD.


Assuntos
Endotélio Linfático/metabolismo , Endotélio Linfático/patologia , Endotélio Vascular/metabolismo , Endotélio Vascular/patologia , Vasculite/patologia , Proteínas de Transporte Vesicular/metabolismo , Fator de von Willebrand/metabolismo , Parede Abdominal/patologia , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Linfangite/complicações , Linfangite/diagnóstico , Vasos Linfáticos/metabolismo , Vasos Linfáticos/patologia , Masculino , Pessoa de Meia-Idade , Tromboflebite/complicações , Tromboflebite/diagnóstico , Vasculite/etiologia , Vasculite/metabolismo , Veias/metabolismo , Veias/patologia
8.
Nuklearmedizin ; 46(3): 101-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17549321

RESUMO

UNLABELLED: The AIM of this study was to evaluate the effect of scatter and attenuation correction in region of interest (ROI) analysis of brain perfusion single-photon emission tomography (SPECT), and to assess the influence of selecting the reference area on the calculation of lesion-to-reference count ratios. PATIENTS, METHODS: Data were collected from a brain phantom and ten patients with unilateral internal carotid artery stenosis. A simultaneous emission and transmission scan was performed after injecting 123I-iodoamphetamine. We reconstructed three SPECT images from common projection data: with scatter correction and nonuniform attenuation correction, with scatter correction and uniform attenuation correction, and with uniform attenuation correction applied to data without scatter correction. Regional count ratios were calculated by using four different reference areas (contralateral intact side, ipsilateral cerebellum, whole brain and hemisphere). RESULTS: Scatter correction improved the accuracy of measuring the count ratios in the phantom experiment. It also yielded marked difference in the count ratio in the clinical study when using the cerebellum, whole brain or hemisphere as the reference. Difference between nonuniform and uniform attenuation correction was not significant in the phantom and clinical studies except when the cerebellar reference was used. Calculation of the lesion-to-normal count ratios referring the same site in the contralateral hemisphere was not dependent on the use of scatter correction or transmission scan-based attenuation correction. CONCLUSION: Scatter correction was indispensable for accurate measurement in most of the ROI analyses. Nonuniform attenuation correction is not necessary when using the reference area other than the cerebellum.


Assuntos
Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Transtornos Cerebrovasculares/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Idoso , Cerebelo/anatomia & histologia , Cerebelo/diagnóstico por imagem , Feminino , Lateralidade Funcional , Humanos , Masculino , Pessoa de Meia-Idade , Imagens de Fantasmas
9.
Genetics ; 84(2): 257-66, 1976 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-826446

RESUMO

Effects of a second chromosome male-specific lethal gene, maleless (mle), of Drosophila melanogaster were further studied. It was shown that, although no maternal effect was seen with respect to the male-specific lethality, the lethal stage was influenced by whether parental females were homozygous or heterozygous for mle. Thus, in the former mle/mle males died mostly in the late third instar larval stage, while in the latter practically all males survived to the pupal stage. In the dying mle/mle male pupae complete differentiation of adult external head and thorax structures was often observed but that of abdominal structures was incomplete forming only a few segments in most cases. Imaginal discs from third instar mle/mle male larvae which were produced by mle/mle mothers and were destined to die as larvae were able to differentiate into adult structures upon transplantation into normal third instar larval hosts. A somewhat elaborated version of the previously presented hypothesis (FUKUNAGA, TANAKA and OISHI 1975) was discussed as to the possible presence of a class of sex-specific lethals which are not related to the process of primary sex differentiation.


Assuntos
Drosophila melanogaster , Genes Letais , Sexo , Animais , Cruzamentos Genéticos , Feminino , Genes Recessivos , Heterozigoto , Homozigoto , Larva , Masculino , Mutação , Pupa
10.
Genetics ; 81(1): 135-41, 1975 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-812765

RESUMO

A second chromosome male-specific lethal gene, maleless (mle), in D. melanogaster is described. It kills males but not females in homozygous condition, regardless of whether female parents are heterozygous or homozygous for mle. Many, if not most, homozygous males survive up to the third instar larval stage, but cannot pupate and die eventually as larvae. No interactions with sex-transforming genes, tra and dsx, were observed. It is proposed that mle interacts with a gene(s) on the X chromosome, which is not dosage compensated.


Assuntos
Drosophila melanogaster , Genes Letais , Genes Recessivos , Fenótipo , Animais , Mapeamento Cromossômico , Homozigoto , Larva , Masculino , Sexo
11.
Genetics ; 102(2): 233-43, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6818105

RESUMO

Interactions between a female-specific lethal mutant, Sxlf 1, and each of three male-specific lethal mutants, mle(3)132, msl-2(27) and mle, of Drosophila melanogaster were observed to produce morphological changes in various sexually dimorphic external characters. Chromosomal females heterozygous for Sxlf 1 and homozygous for any one of the male-specific lethals (and to a lesser degree heterozygous for male-specific lethals) sometimes had sex combs, male-type tergites, male-type sternites, male-type anal plates or male-type external genitalia. Penetrance was not high and expression was often incomplete; single individuals never had all the sexually dimorphic structures transformed. When mothers were homozygous for male-specific lethals, higher proportions of female progeny were affected than when mothers were heterozygous, suggesting a maternal effect.


Assuntos
Drosophila melanogaster/genética , Genes Letais , Recombinação Genética , Animais , Cruzamentos Genéticos , Feminino , Masculino , Transformação Genética
12.
Genetics ; 102(2): 223-31, 1982 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6818104

RESUMO

Mutants at three male-specific lethal loci of Drosophila melanogaster (mle, msl-2(27) and mle(3)132) were examined by gynandromorph analysis. In all cases only a very few gynandromorphs with small X/O patches appeared. Most of these small X/O patches were in the abdomen, and the structures in these X/O regions were reduced in size. These results indicate that the primary effects of these mutants are not on any particular organs or tissues, but rather on individual cells, mle and msl-2 have been shown by BELOTE and LUCCHESI (1980a) to be defective in dosage compensation in X/Y males. We suggest that this dosage-compensation defect results in the expression of Minute-like phenotypes in X/O cells, and hence results in the death of X/O males and flies with large X/O tissue areas.


Assuntos
Mecanismo Genético de Compensação de Dose , Drosophila melanogaster/genética , Genes Letais , Animais , Cromossomos/ultraestrutura , Masculino , Fenótipo
13.
Genetics ; 99(3-4): 429-41, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-6806142

RESUMO

In Drosophila, vitellogenins (yolk protein precursors) are synthesized by the female fat body, secreted into the hemolymph and subsequently taken up by the developing oocytes. The male fat body, on the other hand, does not do this even when immature ovaries are transplanted into the body cavity and grow. Thus, the hemolymph vitellogenins serve as an easily detectable sexually dimorphic biochemical marker.--We have examined hemolymph vitellogenins by SDS polyacrylamide gel electrophoresis in flies carrying various sex-transformation mutants (dsx, tra, tra-2 and tra-2OTF) singly and in all possible combinations. Chromosomal females homozygous for tra or tra-2 have no detectable hemolymph vitellogenins, while those homozygous for tra-2OTF exhibit appreciable levels of these proteins. Flies homozygous for dsx, both X/X and X/Y, have hemolymph vitellogenins, although the amount is consistently smaller in the latter. Indeed, X/Y; dsx/dsx is the only genotype in which hemolymph vitellogenins are detected in the X/Y flies. A clear hierarchy of epistasis exists among these sex-transformation mutants when they are examined in various combinations: dsx greater than tra, tra-2 greater than tra-2OTF. Moreover, an interaction between tra-2OTF and tra was seen in these experiments: X/X; tra-2OTF/tra-2OTF flies show the presence of only a trace of hemolymph vitellogenins when they are made heterozygous for tra. These results, combined with observations on gonad morphology, are discussed with respect to the Baker and Ridge (1980) hypothesis of sex determination.


Assuntos
Drosophila melanogaster/genética , Lipoproteínas/biossíntese , Diferenciação Sexual , Vitelogeninas/biossíntese , Animais , Feminino , Genótipo , Gônadas/anatomia & histologia , Hemolinfa/análise , Masculino , Mutação , Fenótipo , Análise para Determinação do Sexo , Cromossomo X
14.
J Med Chem ; 43(20): 3688-98, 2000 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-11020283

RESUMO

In an attempt to design and synthesize potential anticancer agents acting by inhibition of topoisomerase I (top1), a new series of indenoisoquinolines was prepared and tested for cytotoxicity in human cancer cell cultures and for activity against top1. The synthesis relied on the condensation of substituted Schiff bases with homophthalic anhydrides to produce cis-3-aryl-4-carboxyisoquinolones that were cyclized to indenoisoquinolines in the presence of thionyl chloride. Both top1 inhibitory activity and cytotoxicity maximized in a single compound, 6-[3-(2-hydroxyethyl)aminopropyl]-5,6-dihydro-2,3-dimethoxy-8, 9-methylenedioxy-5,11-dioxo-11H-indeno[1,2-c]isoquinoline hydrochloride (19a), which proved to be a very potent top1 inhibitor having a 110 nM mean graph midpoint (MGM) when tested for cytotoxicity in 55 human cancer cell cultures. A number of structurally related indenoisoquinolines were also obtained that had both potent cytotoxicity as well as top1 inhibitory activity. The key feature of the more potent compounds was the presence of an aminoalkyl side chain on the indenoisoquinoline nitrogen atom. The DNA cleavage patterns induced by top1 in the presence of the indenoisoquinolines were different from those seen with camptothecin. Some of the cleavage sites induced by the indenoisoquinolines were different from those seen with camptothecin, and conversely, camptothecin induced unique cleavage sites not apparent with the indenoisoquinolines. However, both camptothecin and the indenoisoquinolines also induced DNA cleavage sites that were the same in both series but varied in intensity. In addition, some of the DNA cleavages seen with the free base of 19a (compound 18c) in the presence of top1 were inhibited at higher drug concentrations, suggesting either a direct inhibition of the enzyme or an alternative mechanism involving DNA intercalation. Consistent with intercalation, compound 18c did unwind DNA.


Assuntos
Antineoplásicos/síntese química , Inibidores Enzimáticos/síntese química , Indenos/síntese química , Isoquinolinas/síntese química , Inibidores da Topoisomerase I , Antineoplásicos/química , Antineoplásicos/farmacologia , DNA Super-Helicoidal/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Humanos , Indenos/química , Indenos/farmacologia , Isoquinolinas/química , Isoquinolinas/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
15.
Metabolism ; 50(4): 477-80, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11288046

RESUMO

The aim of the present study was to investigate the effect of bezafibrate on insulin sensitivity and insulin secretion in 30 non-obese Japanese type 2 diabetic patients with hypertriglyceridemia (serum triglycerides > 150 mg/dL). Insulin sensitivity was measured with homeostasis model assessment insulin resistance (HOMA-IR) proposed by Matthews et al. HOMA-B-cell function, proposed by Matthews et al validated against minimal model-derived insulin secretion, was used to assess pancreatic insulin function. Twenty-two patients were treated with glibenclimide and the rest were treated with diet alone. All patients were treated with bezafibrate (400 mg/d) for 3 months. There were no changes in diet and the dose of any medications used throughout the study. Fasting glucose, insulin, triglycerides, HDL cholesterol, and total cholesterol levels were measured before and after treatment of bezafibrate. After treatment of bezafibrate for 3 months, serum triglyceride levels significantly decreased from 277 +/- 30 to 139 +/- 9 mg/dL (P <.001) and serum HDL cholesterol levels increased significantly from 45 +/- 2 to 52 +/- 2 mg/dL (P =.003). Serum cholesterol level was unchanged during the study (198 +/- 7 v 201 +/- 7 mg/dL, P =.383). Fasting glucose (163 +/- 8 v 139 +/- 6 mg/dL, P =.006) significantly decreased after the treatment with bezafibrate. HbA1c levels decreased, although not statistically significant (7.50 +/- 0.25 v 7.17% +/- 0.19%, P =.147). On the other hand, fasting insulin (9.3 +/- 0.7 v 7.3 +/- 0.5 microU/mL, P =.010) and HOMA-IR (3.61 +/- 0.24 to 2.53 +/- 0.20, P <.001) levels decreased significantly after the treatment with bezafibrate. In contrast, HOMA-B-cell function did not change during the study (41.4 +/- 5.5 v 41.8 +/- 4.7, P =.478). There was no significant difference in body mass index (BMI) levels before and after the therapy (23.0 +/- 0.4 v 23.1 +/- 0.4 kg/m(2), P =.483). From these results, it can be concluded that bezafibrate reduces serum triglycerides, insulin resistance, and fasting blood glucose levels in non-obese Japanese type 2 diabetic patients.


Assuntos
Bezafibrato/farmacologia , Diabetes Mellitus Tipo 2/metabolismo , Hipolipemiantes/farmacologia , Resistência à Insulina/fisiologia , Insulina/metabolismo , Adulto , Idoso , Glicemia/metabolismo , Feminino , Glibureto/uso terapêutico , Humanos , Hipoglicemiantes/uso terapêutico , Japão , Masculino , Pessoa de Meia-Idade
16.
Cell Transplant ; 6(5): 515-9, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9331504

RESUMO

Xenografting must be considered as a means of establishing neural transplantation therapy and of securing fetal neural tissues as donor material. The early stage (embryonic day 8.5, E8.5) embryonic mesencephalic neural plate (NP) from transgenic mice was examined for possible application in effective xenografting therapy. As recipients, Parkinsonian rats treated with 6-hydroxydopamine were used, and as donors, GT4-2 mice into which a beta-galactosidase gene was introduced to allow brain tissue differentiation from the recipients by X-gal staining. Three microscopic pieces of E8.5 GT4-2 mice NP were injected into the striatum of the Parkinsonian rats. Some hosts were given immunosuppressants (cyclophosphamide and FK506) (IS group), others were not (non-IS group). Amphetamine-induced rotation was examined at days 11 and 21 after grafting (D11 and D21, respectively), and morphological investigations were performed using hematoxylin-eosin (H-E), X-gal, and thyrosine hydroxylase (TH) staining. The rotations were counted in 30 of the 38 transplanted rats before and after grafting. Histological data were obtained from 19 of these 30 rats. In 11 of them the grafts survived (survival group) and in the remaining 8, the grafts were unsuccessful (rejection group). In the survival group at D11, the mean number of rotations made by transplanted rats expressed as a percentage of the number before grafting (rotation percentage) decreased to 43.8% (n = 9), which, in comparison with the average of 125.9% (n = 6) in the rejection group, reveals significant behavioral recovery (p < 0.01). The rotation percentage at D21 was 23.8% in the survival group (n = 4) and 84.5% in the rejection group (n = 3). Behavioral recovery was thus seen to improve with time in the survival group. In the IS group (n = 19), the rotation percentages averaged 74.9% (D11, n = 15) and 51.1% (D21, n = 7), while the non-IS group averages were 136.7% (D11, n = 9) and 140.7% (D21, n = 9), indicating a tendency for better behavioral recovery in the IS group than in the non-IS group (p < 0.05). Fifteen IS group rats were studied histologically, 10 (sacrificed on D11, D21) from the survival group and 5 (sacrificed on D11, D21) from the rejection group, In the non-IS group (n = 4), there was a graft in only one rat sacrificed on D11. There were many X-gal positive and TH positive cells in the grafts, suggesting that mouse NP survived, and differentiated into TH positive neurons in the rat brain. Xenografted NP has the potential to cure central nervous system diseases.


Assuntos
Transplante de Tecido Encefálico/métodos , Transplante de Tecido Fetal/métodos , Mesencéfalo/transplante , Doença de Parkinson Secundária/cirurgia , Anfetamina/farmacologia , Animais , Ciclofosfamida/uso terapêutico , Ectoderma/transplante , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/uso terapêutico , Mesencéfalo/citologia , Mesencéfalo/embriologia , Camundongos , Camundongos Transgênicos , Oxidopamina/farmacologia , Ratos , Tacrolimo/uso terapêutico , Transplante Heterólogo , Tirosina 3-Mono-Oxigenase/análise , beta-Galactosidase/análise
17.
Cell Transplant ; 8(4): 435-41, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10478726

RESUMO

After cerebral infarction, necrosis in neural tissues is not usually repaired or reconstructed by the injured brain. We therefore examined the effects on postinfarction repair of implanting central nervous system (CNS) stem cells together with mesenchyme, because CNS stem cells can be expected to adapt and survive in the adult brain. Cerebral infarction was induced by the Koizumi-Longa method, using the adult male spontaneous hypertensive rat model. Reperfusion was performed an hour after middle cerebral artery occlusion. The rat mesencephalic neural plate at the early somite stage (embryonic day 10.5) together with the adjacent ventral mesenchymal tissues was dissected out under the microscope and immediately implanted into the ischemic rat striatum. One month later, the cognitive function was evaluated by the Morris water maze method. Histologic and immunohistochemical examinations of the graft were made with hematoxylin-eosin (H&E), neurofilament-200, and tyrosine hydroxylase (TH) stains. In the water maze study, mean latency times required to reach an escape platform in the implanted animals with surviving grafts were found to be shorter than in those without grafts, but longer than in normal animals. In the spatial probe trial, the number of animals seen to cross the area in the pool where the platform had been located was greater in the implanted rats with surviving grafts than in other groups. Multiple vascularization in the grafted area was observed histologically in H&E-stained tissues, and neurofilament-200-positive cells were recognized in the graft. TH staining revealed within the graft many immunoreactive neuron-like cell bodies with long dendrites. It was suggested that grafted CNS stem cells with mesenchyme may survive and differentiate into mature CNS tissue within the adult ischemic rat brain, constructing vessels in and around the grafts, and may therefore have the potential to be effective in the recovery of the cognitive function of the rat model.


Assuntos
Isquemia Encefálica/cirurgia , Transplante de Tecido Encefálico , Transplante de Tecido Fetal , Neovascularização Fisiológica , Neurônios/transplante , Transplante de Células-Tronco , Fatores Etários , Animais , Arteriopatias Oclusivas/cirurgia , Diferenciação Celular , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/cirurgia , Infarto Cerebral/cirurgia , Cognição , Corpo Estriado/irrigação sanguínea , Corpo Estriado/cirurgia , Sobrevivência de Enxerto , Masculino , Aprendizagem em Labirinto , Mesoderma/citologia , Proteínas de Neurofilamentos/análise , Neurônios/química , Neurônios/enzimologia , Ratos , Ratos Endogâmicos SHR , Tempo de Reação , Células-Tronco/química , Células-Tronco/enzimologia , Tirosina 3-Mono-Oxigenase/análise
18.
Cell Transplant ; 9(5): 717-24, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11144972

RESUMO

Reconstruction of neurocircuits by transplanted cells is expected to become an effective therapy for brain damage. In order to establish the transplantation therapy, it is necessary to find transplantable cells capable of reconstructing the lesioned neurocircuitry. We have reported that the younger neuronal cells such as neural stem cells are useful transplant materials because of their vigorous capacity for forming abundant neurites. On the other hand, it was reported that myelin-associated neurite growth inhibitor prevents neurite regeneration. In this study, we used rat fetal neuronal cells to examine the neurite growth capacity in the presence of mature CNS myelin. Crude CNS myelin was prepared from the brains of adult Wistar rats using previously described procedures. Testing wells were precoated with poly-L-lysine and additionally by over-night drying of a suspension containing 0, 5, 10, 15, or 20 microg/cm2 of the crude myelin protein. On embryonic days 10, 12, 15, and 17 (E10, E12, E15, and E17) embryos were surgically removed, mesencephalic neural plates were dissected out from the E10 embryos, and midbrain cells were taken from the E12, E15, and E17 embryos. The neural plates and midbrain cells were placed on the myelin-coated wells. After 24 h of culture (72 h in the case of neural plates), the number of surviving cells and the length of the neurites were examined immunocytochemically using anti-neurofilament (NF) antibody. Neurite length was measured by image analyzer Luzex-F. The mesencephalic neural plate was able to grow neurites even on 20 microg/cm2 central myelin. Almost the same number of midbrain cells attached themselves to the wells without myelin in every culture obtained from various stages of embryos. The number of cells attached on the myelin-coated wells decreased with the concentration of myelin. The number of NF-positive cells was higher in cultures of materials obtained from older embryos than in cultures obtained from younger embryos. The younger cells grew longer neurites than the older cells in the myelin noncoated wells. Neurite growth was inhibited strongly when the concentration of the central myelin was 10 microg/cm2 or greater, but on the 5 microg/cm2 myelin, the younger the cells were, the longer neurites they had. When the length of the longest neurites in one field of the image analyzer was further examined in the same way, the younger the cells were, the longer their axons grew on 0 and 5 microg/cm2 myelin. Thus, CNS myelin was seen to be a significant inhibitor of the recovery of injured neural tissue of the adult CNS. Younger cells grew longer neurites than older cells on CNS myelin, and so it was suggested that neural stem cells or younger neurons may serve as tissue for transplantation therapy.


Assuntos
Bainha de Mielina/fisiologia , Neuritos/ultraestrutura , Neurônios/fisiologia , Animais , Encéfalo/citologia , Encéfalo/embriologia , Encéfalo/fisiologia , Diferenciação Celular , Sobrevivência Celular , Células Cultivadas , Neuritos/química , Proteínas de Neurofilamentos/análise , Ratos , Ratos Wistar
20.
J Dent Res ; 67(3): 588-91, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3170897

RESUMO

The adherence of Streptococcus sanguis ATCC 10556, S. sanguis ATCC 10557, S. mutans Ingbritt, and S. mutans OMZ 176 to the surfaces of composite resins, amalgam alloys, and a Au-Ag-Pd alloy was measured. Adhesion was correlated with values for hydrophobicity and zeta-potential of the bacteria and the restorative materials. The hydrophobicity of the restoratives showed a positive correlation between the numbers of adherent S. sanguis cells, suggesting that hydrophobic interactions are important for the adherence of this bacterial species. In contrast, the numbers of adherent S. mutans cells showed a positive correlation with the zeta-potential of the restoratives, suggesting that electrostatic interactions are important in adherence of this bacterium.


Assuntos
Aderência Bacteriana , Resinas Compostas , Amálgama Dentário , Streptococcus mutans/fisiologia , Streptococcus sanguis/fisiologia , Fenômenos Químicos , Físico-Química , Ligas Dentárias , Propriedades de Superfície
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