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1.
J Stroke Cerebrovasc Dis ; 29(7): 104852, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32404286

RESUMO

BACKGROUND: Branch atheromatous disease is an ischemic stroke, involving occlusion or severe stenosis of the perforating artery, causing neurologic symptoms and serious sequelae. We aimed to investigate initial morphometric and hemodynamic characteristics of the vertebral artery immediately post-onset to predict lesion expanding. METHODS: This case-control study collected demographic, historical, and physical examination data from 44 patients with branch atheromatous disease in the pons at admission. The maximum ischemic pons area and stenosis rate in the basilar artery were calculated using magnetic resonance images. Diameter, velocity, and flow volume of the vertebral arteries were measured using carotid artery ultrasonography. Correlations between ischemic lesion extent and these parameters were investigated. RESULTS: Patients were assigned to groups of less (Group 1) or more (Group 2) than the median maximum ischemic area in the pons, calculated from magnetic resonance images (121.6 mm2). Modified Rankin scale scores were significantly worse in Group 2. Blood pressure and blood findings were similar between groups. Group 2 showed significantly higher basilar artery stenosis rates. Flow volume, velocity, peak systolic velocity, and end-diastolic velocity in the vertebral artery on both sides were significantly decreased in Group 2. CONCLUSIONS: Deteriorated vertebral artery hemodynamics caused a more extensive ischemic lesion in branch atheromatous disease in the pons. Evaluation of the vertebral using carotid artery ultrasonography in the acute phase may be useful for predicting disease progression.


Assuntos
Artérias Carótidas/diagnóstico por imagem , Circulação Cerebrovascular , Hemodinâmica , Arteriosclerose Intracraniana/diagnóstico por imagem , Placa Aterosclerótica , Ponte/irrigação sanguínea , Ultrassonografia Doppler de Pulso , Artéria Vertebral/diagnóstico por imagem , Insuficiência Vertebrobasilar/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo , Artérias Carótidas/fisiopatologia , Estudos de Casos e Controles , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Arteriosclerose Intracraniana/fisiopatologia , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Artéria Vertebral/fisiopatologia , Insuficiência Vertebrobasilar/fisiopatologia
2.
BMC Neurosci ; 16: 92, 2015 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-26667128

RESUMO

BACKGROUND: Hippocampal neurons in the brain polarize to form multiple dendrites and one long axon. The formation of central synapses remains poorly understood. Although several of the intracellular proteins involved in the clustering of central neurotransmitter receptors and ion channels have been identified, the signals involved in pre- and postsynaptic differentiation remain elusive. Synaptotagmin1 is an abundant and important presynaptic vesicle protein that binds Ca(2+) (J Biol Chem 277:7629-7632, 2002) in regulation of synaptic vesicle exocytosis at the synapse. Synapse consists of the formation of synaptic connections and requires precise coordination of Synaptotagmin1. It was reported Synaptotagmin1 plays an important roles in the formation of axonal filopodia and branches in chicken forebrain neurons (Dev Neurobiol 73:27-44, 2013). To determine if Synaptotagmin1 could have a role in formation of axon in hippocampal neurons, we investigated the effects of Synaptotagmin1 overexpression and knockdown using the shRNA on the growth and branching of the axons of primary hippocampal neurons. We showed that overexpression of Synaptotagmin1 leads to abnormal multiple axon formation in cultured rat hippocampal neurons. RESULTS: We first examined the effects of Synaptotagmin1 on the numbers of axon and dendrites. We found that the overexpression of Synaptotagmin1 led to the formation of multiple axons and induced an increase in the number of endogenous postsynaptic protein Homer1c clusters in cultured hippocampal neurons. Endogenous initial segment of axon was detected with anti-sodium channel (anti-NaCh) antibody and with anti-Tau1 (J Neurosci 24: 4605-4613, 2004). The endogenous initial segment of axon was stained with anti-NaCh antibodies and with anti-Tau1 antibodies. Then the numbers of prominence dyed positive were counted as axon. We attempted to specifically knockdown the endogenous Synaptotagmin1 with small hairpin RNAs (shRNAs). To further dissect the functions of endogenous Synaptotagmin1 in neuronal polarity, we used the shRNA of Synaptotagmin1 that specifically blocks the existence of endogenous Synaptotagmin1. When the shRNA of Synaptotagmin1 was introduced to the cells, the number of axons and dendrites did not change. CONCLUSIONS: These results indicate that the accumulation of Synaptotagmin1 may play an important role in axon/dendrite differentiation.


Assuntos
Axônios/fisiologia , Hipocampo/fisiologia , Sinaptotagmina I/metabolismo , Animais , Proteínas de Transporte/metabolismo , Células Cultivadas , Dendritos/fisiologia , Técnicas de Silenciamento de Genes , Células HEK293 , Hipocampo/citologia , Proteínas de Arcabouço Homer , Humanos , Microscopia de Fluorescência , RNA Interferente Pequeno , Ratos Wistar , Sinaptotagmina I/genética
3.
Int J Mol Sci ; 15(2): 1812-25, 2014 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-24469316

RESUMO

The possibility of nanoparticle (NP) uptake to the human central nervous system is a major concern. Recent reports showed that in animal models, nanoparticles (NPs) passed through the blood-brain barrier (BBB). For the safe use of NPs, it is imperative to evaluate the permeability of NPs through the BBB. Here we used a commercially available in vitro BBB model to evaluate the permeability of NPs for a rapid, easy and reproducible assay. The model is reconstructed by culturing both primary rat brain endothelial cells and pericytes to support the tight junctions of endothelial cells. We used the permeability coefficient (P(app)) to determine the permeability of NPs. The size dependency results, using fluorescent silica NPs (30, 100, and 400 nm), revealed that the Papp for the 30 nm NPs was higher than those of the larger silica. The surface charge dependency results using Qdots® (amino-, carboxyl-, and PEGylated-Qdots), showed that more amino-Qdots passed through the model than the other Qdots. Usage of serum-containing buffer in the model resulted in an overall reduction of permeability. In conclusion, although additional developments are desired to elucidate the NPs transportation, we showed that the BBB model could be useful as a tool to test the permeability of nanoparticles.


Assuntos
Barreira Hematoencefálica/metabolismo , Técnicas de Cultura de Células , Nanopartículas/metabolismo , Animais , Barreira Hematoencefálica/citologia , Células Endoteliais , Nanopartículas/química , Tamanho da Partícula , Pericitos , Permeabilidade , Ratos , Dióxido de Silício/química , Dióxido de Silício/metabolismo , Propriedades de Superfície
4.
Int J Mol Sci ; 15(7): 11742-59, 2014 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-24992594

RESUMO

Several in vivo studies suggest that nanoparticles (smaller than 100 nm) have the ability to reach the brain tissue. Moreover, some nanoparticles can penetrate into the brains of murine fetuses through the placenta by intravenous administration to pregnant mice. However, it is not clear whether the penetrated nanoparticles affect neurogenesis or brain function. To evaluate its effects on neural stem cells, we assayed a human neural stem cell (hNSCs) line exposed in vitro to three types of silica particles (30 nm, 70 nm, and <44 µm) and two types of titanium oxide particles (80 nm and < 44 µm). Our results show that hNSCs aggregated and exhibited abnormal morphology when exposed to the particles at concentrations = 0.1 mg/mL for 7 days. Moreover, all the particles affected the gene expression of Nestin (stem cell marker) and neurofilament heavy polypeptide (NF-H, neuron marker) at 0.1 mg/mL. In contrast, only 30-nm silica particles at 1.0 mg/mL significantly reduced mitochondrial activity. Notably, 30-nm silica particles exhibited acute membrane permeability at concentrations =62.5 µg/mL in 24 h. Although these concentrations are higher than the expected concentrations of nanoparticles in the brain from in vivo experiments in a short period, these thresholds may indicate the potential toxicity of accumulated particles for long-term usage or continuous exposure.


Assuntos
Nanopartículas , Células-Tronco Neurais/efeitos dos fármacos , Dióxido de Silício/farmacologia , Titânio/farmacologia , Linhagem Celular , Humanos , Mitocôndrias/efeitos dos fármacos , Nestina/genética , Nestina/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Proteínas de Neurofilamentos/genética , Proteínas de Neurofilamentos/metabolismo , Dióxido de Silício/química , Titânio/química
5.
PLoS One ; 19(3): e0301280, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38547217

RESUMO

Japan has the highest life expectancy worldwide. Older adults who experience economic insecurity may refrain from seeking medical consultation or using long-term care insurance, and these behaviors may increase the incidence and progression of frailty. This study conducted a cross-sectional survey to identify factors related to a sense of economic insecurity among older adults who participate in social activities, and identified support measures. In total, 1,351 older adults aged ≥65 years who had participated in social activities voluntarily completed an anonymous self-administered questionnaire. The questionnaire encompassed their physical, cognitive, social, and psychological conditions, and economic insecurity. We performed univariate analysis considering a sense of economic insecurity as the dependent variable, and conducted multiple logistic regression analysis (forced entry method) considering the independent variables with p<0.1 as the covariates. Among the 872 filled questionnaires, 717 were analyzed as they had no missing data with respect to the responses to survey questions (valid response rate was 53.1%). Analysis results showed that 43.6% of the older adults had a sense of economic insecurity, which was most common among those aged 75-84 years, accounting for 47.3%, followed by those aged 65-74 years accounting for 44.1%, and those aged ≥85 years accounting for 31.5% (p<0.05). The sense of economic insecurity was not associated with physical conditions, subjective symptoms of dementia, or social conditions; however, it grew with increased loneliness (OR: 1.71, 1.002-2.92, p = 0.049) and decreased with an increased subjective sense of well-being (OR: 0.86, 0.81-0.92, <0.001). Economic insecurity among older adults was not associated with physical, cognitive, or social aspects, as reported in previous studies. The survey respondents constituted older adults who participate in social activities. Maintaining interactions within the community, even in old age, may prevent loneliness and improve subjective health.


Assuntos
Fragilidade , Humanos , Idoso , Estudos Transversais , Inquéritos e Questionários , Japão
6.
J Neurosci Res ; 91(7): 882-9, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23606502

RESUMO

Activity-dependent reorganizations of central neuronal synapses are thought to play important roles in learning and memory. Although the precise mechanisms of how neuronal activities modify synaptic connections in neurons remain to be clarified, the activity-induced neuronal presynaptic proteins such as synaptotagmin1 may contribute to the onset of synaptic remodeling. To understand better the physiological roles of synaptotagmin1, we first examined the prolonged effects of neuronal stimulation capable of inducing synaptotagmin1 on the distribution of a postsynaptic proteins (PSD) protein Homer1c by immunostaining. Previously we found that glutamate stimulation induced other postsynaptic proteins, such as postsynaptic density-95 (PSD95), a biphasic change with an initially diffuse distribution after 30 min to 1 hr, followed by reassembly to more than the original level after 4-8 hr, suggesting that glutamate stimulation induces a global biphasic alteration in synaptic structures. To dissect further the functions of synaptotagmin1 in the activity-induced synaptic remodeling, short hairpin RNA (shRNA) vectors that specifically block the expression of endogenous synaptotagmin1 were constructed. When the shRNA of synaptotagmin1 was introduced to the neurons, the activity-induced changes were almost completely suppressed. We found that synaptotagmin1 contributes to the postsynaptic remodeling in a retrograde manner. Our data indicate that synaptotagmin1 regulates the activity-induced biphasic changes of post- and presynaptic sites.


Assuntos
Proteínas de Transporte/metabolismo , Hipocampo/citologia , Neurônios/fisiologia , Sinaptotagmina I/metabolismo , Animais , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Ácido Glutâmico/farmacologia , Proteínas de Arcabouço Homer , Humanos , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Plasticidade Neuronal , Neurônios/citologia , Neurônios/efeitos dos fármacos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Sinaptotagmina I/genética , Fatores de Tempo , Transfecção
7.
Microscopy (Oxf) ; 72(1): 49-55, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36269105

RESUMO

The usefulness of the transmission electron microscope (TEM) for pathological diagnosis is apparent. However, high operating costs and other disadvantages have limited the ability to maintain and operate a TEM. In recent years, a general-purpose benchtop low-vacuum scanning electron microscope (LVSEM), which is inexpensive and easy to operate, has been developed and is expected to be applied in electron microscopic pathological diagnosis. To date, we have previously observed TEM ultrathin sections of Immunoglobulin A (IgA) nephropathy with a benchtop LVSEM using an ultra variable-pressure detector (UVD) and a newly developed holder for observing scanning transmission electron microscope (STEM) images (UVD-STEM holder) and compared the images with those obtained with typical TEM observations. We reported the results in the 53rd Annual Meeting of the Japanese Society for Clinical Molecular Morphology and the 64th Symposium of The Japanese Society of Microscopy and discussed the validity of the methods in the pathological diagnosis of IgA nephropathy and other renal diseases. As a result, we demonstrated the potential for pathological diagnosis using benchtop LVSEM. In this study, we similarly examined typical kidney diseases such as membranous nephropathy, lupus nephritis and amyloidosis. We could obtain sufficient data for the pathological diagnosis of IgA nephropathy, membranous nephropathy and lupus nephritis. However, it is difficult to detect amyloid fibres that are characteristic of amyloidosis. The development of this method is expected to expand the possibilities for pathological diagnosis using electron microscopy, including its application to other diseases.


Assuntos
Glomerulonefrite por IGA , Glomerulonefrite Membranosa , Nefrite Lúpica , Humanos , Vácuo , Glomerulonefrite por IGA/diagnóstico , Glomerulonefrite por IGA/patologia , Glomerulonefrite Membranosa/diagnóstico , Glomerulonefrite Membranosa/patologia , Microscopia Eletrônica , Imunoglobulina A , Biópsia
8.
Front Public Health ; 11: 1216831, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37732091

RESUMO

Introduction: Due to declining birthrates and aging populations, parental care is going to place a greater burden on younger generations in the future, especially in East Asia where it is more common for children to provide care regardless of whether there is a national long-term care insurance program. Therefore, it has become important to understand the younger generation's views on parental care. Methods: An explorative, metathematic qualitative study design was used. Data collection relied on semi-structured interviews, of which 19 Chinese and 19 Japanese university students were conducted from December 2021 to July 2022 using a snowball sampling method. Metatheme analysis was then used to identify broad cross-cultural metathemes and inter-relationships on parental care. Results: Three parental care metathemes were identified for the perspectives of parental care: distrust of leaving parental care to others, responsibility to care for their parents, and importance of parent-child interactions about parental care. Conclusion: To improve social support for care, both countries must improve long-term care service delivery and healthcare systems and ensure that there is a trusting relationship between healthcare professionals and the public. Governments should also ensure that adult children receive assistance to balance their work, life, and parental care responsibilities. The findings provide several practical suggestions for improving healthcare systems in China and Japan through the younger generations' views.


Assuntos
Comparação Transcultural , População do Leste Asiático , Humanos , Pais , Estudantes , Universidades , Filhos Adultos , Cuidadores
9.
Front Psychol ; 14: 1256110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023053

RESUMO

Introduction: With the declining birth rate and increasingly aging population in Japan, an increased care burden may be placed on the family and the younger generation will address challenging circumstances when they can care for their parents. This study aimed to develop a scale for examining the perspectives of Japanese university students on parental care and determines its reliability and validity. Methods: A web-based survey on a total of 408 Japanese students was adopted. This study performed exploratory and confirmatory factor analyses to obtain the underlying factors of the scale. Reliability was verified using Cronbach's α coefficient and Spearman-Brown's split-half reliability α coefficient. Validity was verified through sample, criterion-related, and convergent and discriminant validity. Results: In total, the study identified a three-factor 11 item-scale. Cronbach's α for the scale was 0.901, and the Cronbach's α and split-half reliability α coefficients of each factor were greater than 0.7. Three factors explained 64.6% of the total variance. The model indicators were χ2/df = 2.241, comparative fit index (CFI) = 0.951, incremental fit index (IFI) = 0.951, TLI = 0.942, root mean square error of approximation (RMSEA) = 0.078 (p < 0.001). Thus, the study confirmed that the convergent and discriminant validity is acceptable. Correlations were noted for criterion-related validity (r = 0.675, p < 0.001). Discussion: The results show that the scale for examining the perspective of Japanese university students on parental care was confirmed with good reliability and validity.

10.
Heliyon ; 7(11): e08318, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34816032

RESUMO

Tumor necrosis frequently occurs in malignant tumors, showing rapid growth and invasion. This phenomenon is generally regarded as simple ischemic necrosis due to insufficient tumor vessels and blood supply. However, the necrotic tissue contains high amount of nuclear substances, DNA, and nucleoproteins that may affect the surrounding tumor cells by promoting or suppressing the tumor cell growth in vivo. This study focused on the effects of an externally administered water-soluble nuclear crude extract (SNE) containing nuclear protein and oligonucleotides on several human cancer and noncancer cell lines. The results demonstrated that the SNE suppressed cell growth in cancer and noncancer cells in vitro. Through the flow cytometry analysis of the nuclear DNA content, it was observed that the SNE increased and decreased cell proportion in the S and G2/M phases, respectively, thereby suggesting that the cell growth inhibition was due to cell cycle delay, and not due to apoptosis. These studies suggest that the high-concentration of extracellular nucleotides generated as a result of tumor necrosis and/or released from infiltrated neutrophils could suppress the growth of surrounding cancer and intrinsic cells, which provides us some insights into an alternative anticancer strategy for patients with highly malignant necrotic tumor.

11.
J Rural Med ; 14(2): 156-164, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31788137

RESUMO

Objective: The present study aimed to examine the role that caregiver burden plays in the familial functioning, social support, and quality of family life (QOFL) of caregivers of elderly family members with dementia. Methods: A survey was conducted with 200 primary caregivers of elderly dementia patients who resided in prefecture "S". The questionnaire consisted of items that required demographic information, the Japanese versions of the Zarit Burden Inventory (ZBI) and the Family Adaptability and Cohesion Evaluation Scales (FACES II), and scales that measure quality of family life and social support. On the basis of the median ZBI score (i.e., 30.8), participants were divided into two groups: group A (i.e., ZBI score < 30) and group B (i.e., ZBI score > 30). Stepwise multiple regression analysis was conducted with QOFL as the dependent variable. Version 24 of the Statistical Package for the Social Sciences for Windows was used to conduct all the statistical analyses; the statistical significance level was specified as 0.05. Results: Group A and B obtained average ZBI scores of 18.5 and 43.8, respectively. The study targeted 81 patients from group A (average age = 61.0 years) and 77 patients from group B (average age = 61.7 years). Time that was spent on caregiving tasks was significantly higher for group B, when compared to group A. In addition, significant differences in cohesion and adaptability, which are two dimensions that are measured by the FACES II, and QOFL emerged between the two groups. The results of the multiple regression analysis showed that cohesion (ß = 0.38), practical support (ß = 0.32), adaptability (ß = 0.30), and living arrangement (ß = -0.12) significantly predicted QOFL. Conclusion: Family cohesion and adaptability are indicators of healthy familial functioning. In order to improve the QOFL of caregivers of elderly dementia patients, it is necessary to strengthen emotional ties, maintain emotional attachment, and flexibly respond to the burden of nursing care and changes in power structures and role relationships.

12.
Okajimas Folia Anat Jpn ; 95(2): 23-27, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30504647

RESUMO

In this study, the results of our previously reported technique of quantitative analysis by using microscopic image analysis of tissue image slices to calculate the proportion of the area of the tunica media occupied by of elastic fibers was compared with Janzen et al.'s technique at the carotid bifurcation. This particularly analyzed the area of transition between the common carotid and the internal carotid, to observe the quantitative changes in elastic fiber content. The data obtained from our quantitative analysis of elastic fibers were clearly at variance with those obtained by counting the number of elastic fibers. The amount of elastic fibers in the tunica media (the elastic fiber ratio) decreased from the proximal carotid artery (the common carotid) to the bifurcation, then peaked in the internal carotid immediately after the bifurcation before declining again.


Assuntos
Artérias Carótidas/anatomia & histologia , Tecido Elástico/anatomia & histologia , Microscopia/métodos , Túnica Média/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade
13.
Okajimas Folia Anat Jpn ; 93(4): 119-125, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28637995

RESUMO

The middle meningeal artery (MMA) can play an important role in the surgical revascularization. However, the MMA can be easily injured if it passes through a bony canal. We investigated the morphological and histological features of the bony canal to improve surgical results. MATERIALS AND METHODS: Fifty adult dry skulls were investigated. The length of the bony canal and the distance from the orbital rim to the bony canal were measured. Additionally, 28 cadaveric heads were examined histologically. RESULTS: Sixty-three bony canals were found in 43 skulls. The mean length of bony canals was 9.2 mm, and the mean distance from the orbital rim was 24.0 mm. The bony canal ran mainly from the sphenoid bone (69.8%) to the parietal bone (73.0%). Histologically, both sides of the meningeal grooves gradually closed the distance, and formed the bony canal. The MMA inside the bony canal was enveloped with collagen tissues, divided into branches, and was accompanied by the vein. CONCLUSIONS: The bony canal is located around the pterion and is formed during bone growth. The MMA is covered with collagen tissues inside the bony canal. It is possible to safely expose and preserve the MMA during craniotomy with careful drilling.


Assuntos
Artérias Meníngeas/anatomia & histologia , Crânio/anatomia & histologia , Feminino , Humanos , Masculino
14.
NeuroRehabilitation ; 39(3): 413-22, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27589511

RESUMO

BACKGROUND: The elucidation of the relationship between the morphology of the peripheral nerves and the diseases would be valuable in developing new medical treatments on the assumption that characteristics of the peripheral nerves in females are different from those in males. METHODS: We used 13 kinds of the peripheral nerve. The materials were obtained from 10 Japanese female and male cadavers. We performed a morphometric analysis of nerve fibers. We estimated the total number of myelinated axons, and calculated the average transverse area and average circularity ratio of myelinated axons in the peripheral nerves. RESULTS: There was no statistically significant difference in the total number, average transverse area, or average circularity ratio of myelinated axons between the female and male specimens except for the total number of myelinated axons in the vestibular nerve and the average circularity ratio of myelinated axons in the vagus nerve. CONCLUSIONS: The lower number of myelinated axons in the female vestibular nerve may be one of the reasons why vestibular disorders have a female preponderance. Moreover, the higher average circularity ratio of myelinated axons in the male vagus nerve may be one reason why vagus nerve activity to modulate pain has a male preponderance.


Assuntos
Nervos Periféricos/anatomia & histologia , Nervos Periféricos/patologia , Doenças do Sistema Nervoso Periférico/patologia , Idoso , Idoso de 80 Anos ou mais , Axônios/ultraestrutura , Cadáver , Contagem de Células , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Bainha de Mielina/ultraestrutura , Fibras Nervosas/ultraestrutura , Caracteres Sexuais , Doenças Vestibulares/patologia , Nervo Vestibular/patologia , Nervo Vestibular/ultraestrutura
15.
J Biochem ; 137(5): 617-23, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15944415

RESUMO

Homer family proteins are encoded by three genes, homer1, 2 and 3. Most of these proteins are expressed constitutively in nervous systems and accumulated in postsynaptic regions. However, the functional significance of these proteins, especially the significance of the distinction among the proteins encoded by homer1, 2 and 3, is still obscure. In the present study, we isolated a cDNA clone encoding a novel protein by two-hybrid system screening using the C-terminal half of Homer2b as the bait. This protein, termed 2B28, has 297 amino acid residues and contains three major domains: a UBA domain, a coiled-coil region, and a UBX domain. When expressed in HEK293T cells, 2B28 showed colocalization with uniquitin and enhanced the expression levels of IkappaB or Homer1a proteins, which are known to be degraded by proteasomes, indicating that 2B28 is involved in ubiquitin-proteasome functions. 2B28 specifically interacted and colocalized with Homer2 proteins, but not with Homer1 proteins. So far, we have identified no counterpart of 2B28 for Homer1 experimentally or in the protein databases. These results suggest that the specific interaction of 2B28 with Homer2 may play a role in regulation of protein degradation by ubiquitin-proteasome systems and that this function may be specific to Homer2 proteins among Homer family proteins.


Assuntos
Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica , Complexo de Endopeptidases do Proteassoma/biossíntese , Ubiquitina/biossíntese , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Animais , Células COS , Proteínas de Transporte/genética , Chlorocebus aethiops , Proteínas de Arcabouço Homer , Humanos , Dados de Sequência Molecular , Isoformas de Proteínas/metabolismo , Ratos , Alinhamento de Sequência , Técnicas do Sistema de Duplo-Híbrido
16.
Anticancer Res ; 35(11): 6069-74, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26504031

RESUMO

BACKGROUND: Transduction of foreign molecules into cells is an important technique to investigate the functions of corresponding molecules and/or targets. Recently, a mass-producible nanoprinting perforator was devised enabling for large-scale, high-performance drug or nucleic-acid transfer into cells without cell damage. Since little is known on the performance of the system, we investigated its effects on a malignant glioma cell line. MATERIALS AND METHODS: Photosensitization was performed by the Cell Stamper CP-01. The malignant U373MG glioma cell line was used for transduction. RESULTS: Photosensitization transduced FITC-conjugated albumin into cells. Trypan blue inclusion test demonstrated membrane disintegration by the procedure and scanning electron microscopy disclosed perforation of the cell membrane. CONCLUSION: Local oxidation reaction during the nanoprinting caused reversible membrane perforation. Morphological findings from the current study support the above mechanism, therefore the specific printing system might be convenient for transduction of foreign molecules into malignant glioma cells.


Assuntos
Membrana Celular/química , Glioma/patologia , Nanotubos/química , Fotoquímica , Fármacos Fotossensibilizantes/farmacologia , Polímeros/química , Albuminas/administração & dosagem , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Glioma/tratamento farmacológico , Humanos , Luz , Microscopia Eletrônica de Varredura , Células Tumorais Cultivadas
17.
Neurosci Lett ; 354(2): 143-7, 2004 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-14698459

RESUMO

In cultured rat hippocampal neurons, overexpression of Homer1a/Vesl-1S, an inducible protein upregulated by seizure or long-term potentiation, caused a reduction of punctate distribution of a postsynaptic protein Homer1c/Vesl-1L, without significant decrease in its total amount. Clusters of F-actin were also decreased. Treatments of cells with BDNF or a proteasome inhibitor, which cause increase in the expression level of endogenous Homer1a, also resulted in the reduction of Homer1c puncta. These results indicate that the accumulation of Homer1a, either exogenously expressed or endogenously induced, caused redistribution and dispersion of postsynaptic clusters of Homer1c and F-actin, suggesting an important role of Homer1a in synaptic remodeling.


Assuntos
Proteínas de Transporte/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Membranas Sinápticas/metabolismo , Transmissão Sináptica/genética , Actinas/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Proteínas de Transporte/genética , Células Cultivadas , Cisteína Endopeptidases/metabolismo , Hipocampo/citologia , Proteínas de Arcabouço Homer , Potenciação de Longa Duração/genética , Complexos Multienzimáticos/antagonistas & inibidores , Complexos Multienzimáticos/metabolismo , Plasticidade Neuronal/genética , Neurônios/citologia , Neuropeptídeos/genética , Complexo de Endopeptidases do Proteassoma , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ratos , Convulsões/genética , Convulsões/metabolismo , Membranas Sinápticas/genética , Regulação para Cima/genética
18.
Anim Reprod Sci ; 72(3-4): 185-96, 2002 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-12137981

RESUMO

The effect of energy status on the response of luteinizing hormone (LH) pulse frequency to acute short-term energy deficiency created by fasting in estradiol-treated ovariectomized Shiba goats was studied in two experiments. In experiment 1, eight goats whose mean body weight (BW) was 25.6 +/- 5.8 (mean +/- S.D.)kg were fed 500 g hay cubes daily for 1 week. Then they were fasted for 3 days. Blood samples were collected for 4 h at 6 min intervals on the last day of feeding, first, second and third day of fasting for LH analysis. The goats were divided into light (<24 kg, n = 4) and heavy (> or =24 kg, n = 4) groups for data analysis. There was no difference in LH pulse frequency between the last day of feeding and each day of fasting in the heavy group. LH pulse frequency was significantly (P < 0.05) suppressed on the second day (3.3 +/- 1.3 pulses/4 h) and on the third day (2.3 +/- 1.9 pulses/4 h) relative to the day prior to fasting (4.8 +/- 1.5 pulses/4 h) in the light group. In experiment 2, BW plus a body mass index (BMI (body weight (kg)/withers height (m)/body length (m))/10 [corrected]) were measured to define energy status. Nine goats (BW, 25.6 +/- 5.8 kg) were fed 500 g hay cubes daily for a week and then fasted for 3 days. Then they were divided into two groups offered either a maintenance (n = 4) or a restricted (n = 5) level of feeding for 4 weeks. The restricted level of feeding was 30% of maintenance requirement based on the BW recorded weekly. The feeding level was then adjusted to maintain BW for a further week followed by 3 day fasting for restricted animals. Blood samples were collected for 6 h at 10 min intervals on the day prior to fasting and on third day of fasting before and after the dietary manipulation. BW (26.6 +/- 2.2 to 26.8 +/- 3.8 kg) and gBMI (8.4 +/- 0.4 to 7.8 +/- 0.3) remained constant over the period prior to fasting for the maintenance animals but were significantly lower (P < 0.05) after 4 weeks for the restricted goats (BW, 26.3 +/- 2.1 to 21.5 +/- 2.4 kg; gBMI, 8.4 +/- 0.9 to 6.9 +/- 0.7). There was no significant difference in the LH pulse frequency between feeding and fasting day in both sampling periods in the maintenance group. In the restricted group, LH pulse frequency was not suppressed by fasting in the first sampling period (6.8 +/- 2.9 to 5.2 +/- 2.5 pulses/6 h), whereas it tended to be suppressed (4.8 +/- 3.1 to 1.6 +/- 2.3 pulses/6 h; P < 0.06) and was significantly (P < 0.05) correlated to body weight (r = 0.70) and gBMI (r = 0.81) after the dietary manipulation. These results suggest that the suppressive effect of short-term energy restriction (fasting) on pulsatile LH secretion is related to body energy status.


Assuntos
Metabolismo Energético , Jejum , Cabras/fisiologia , Hormônio Luteinizante/metabolismo , Ovariectomia/veterinária , Periodicidade , Animais , Índice de Massa Corporal , Peso Corporal , Estradiol/administração & dosagem , Feminino
19.
Anticancer Res ; 32(12): 5299-307, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23225430

RESUMO

BACKGROUND: Urocortin and corticotropin-releasing factors (CRFs) and their receptors are expressed in many organs, including the central nervous system. In this study, the expression of mRNAs of urocortin 1, 2, 3, and CRF and CRF receptors 1 and 2 in malignant glioma, was examined. MATERIALS AND METHODS: The RNAs of human and rat glioma cell lines were isolated. Transcripts in these cells were analyzed using cDNA. In addition, the effects of proliferative and cytotoxic stimulation by serum supplementation, ionizing radiation, and the antineoplastic agent temozolomide were investigated. RESULTS: Human and rat cells transcribed urocortin. CRF receptors were detected in human glioma cells. When human KNS42 cells were exposed to stimulation, transcription was altered according to the specific condition. CONCLUSION: Expression of mRNAs of urocortin and CRF receptors was confirmed in human glioma cell lines. Although the quantities of transcripts varied with the proliferative and cytotoxic stimulation, the overall transcription pattern was not influenced by these stimuli.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , RNA Mensageiro/biossíntese , Receptores de Hormônio Liberador da Corticotropina/genética , Urocortinas/genética , Animais , Neoplasias Encefálicas/metabolismo , Linhagem Celular Tumoral , Glioma/metabolismo , Humanos , Isoformas de Proteínas , RNA Mensageiro/genética , Ratos , Receptores de Hormônio Liberador da Corticotropina/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transcrição Gênica , Urocortinas/biossíntese
20.
Anticancer Res ; 31(10): 3253-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21965733

RESUMO

BACKGROUND: Malignant glioma is an invasive disease of the central nervous system. One of the factors that regulate growth of these tumors is expression of epidermal growth factor receptor (EGFR) in the cells. This study investigated the effects of down-regulation of EGFR on cell proliferation, cell cycle and cytotoxicity to antineoplastic agent. MATERIALS AND METHODS: A short hairpin RNA transcription vector targeting EGFR was transfected into KNS42 cells. Growth curve, cell cycle and sensitivity to temozolomide of the cells were assessed. RESULTS: Transfection inhibited EGFR expression by 50.5%. It prolonged cell doubling time by 25.7%. However, it did not meaningfully alter the cell cycle populations nor increase sensitivity to temozolomide. CONCLUSION: Suppressing expression of EGFR inhibited cell proliferation. However, unlike PTEN expression or ROCK1 down-regulation, it did not alter the cell cycle or increase sensitivity to temozolomide.


Assuntos
Dacarbazina/análogos & derivados , Regulação para Baixo/efeitos dos fármacos , Receptores ErbB/metabolismo , Glioma/patologia , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Dacarbazina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Glioma/enzimologia , Humanos , RNA Interferente Pequeno/metabolismo , Temozolomida , Transfecção , Quinases Associadas a rho/metabolismo
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