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1.
Bioorg Med Chem Lett ; 47: 128195, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34119614

RESUMO

Cytochrome P450 (CYPs) are oxidoreductases distributed in various tissues in plants and animals. Among the CYP families, CYP3A is the most abundant in vivo, particularly in humans, and it is involved in the metabolism of many drugs. It is crucial to measure CYP3A activity for both pharmaceuticals and agrochemicals because inhibition or induction of this enzyme can seriously affect the occurrence of toxicity or efficacy. In the present study, a novel fluorescent probe, 6-(2,5-bis(trifluoromethyl)benzyloxy)-9-(4-methoxy-2-methylphenyl)-3H-xanthen-3-one (BMX, quantum efficiency: 21%), was designed and synthesized. The design was done by photoinduced electron transfer strategy. BMX was specifically metabolized only using CYP3A to generate 2-Me-4-MeO TokyoGreen (quantum efficiency: 85%), resulting in strong fluorescence in the presence of CYP3A isozymes. Protein assays using recombinant human, rat, and mouse CYP isozymes demonstrated the selective metabolism of BMX and production of fluorescence only by CYP3A in all species.


Assuntos
Citocromo P-450 CYP3A/análise , Desenho de Fármacos , Corantes Fluorescentes/química , Xantenos/química , Citocromo P-450 CYP3A/metabolismo , Relação Dose-Resposta a Droga , Transporte de Elétrons , Corantes Fluorescentes/síntese química , Humanos , Estrutura Molecular , Processos Fotoquímicos , Relação Estrutura-Atividade , Xantenos/síntese química
2.
Neuropathology ; 41(6): 468-475, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34791710

RESUMO

Here, we report two cases showing tumor-like white matter lesions; one case was diagnosed as having inflammatory disease, and the other was diagnosed as having astrocytoma. Their outcomes were completely distinct despite similar pathology. Prior to biopsy, perfusion computed tomography (CT) and magnetic resonance imaging (MRI) were conducted. The two mass-forming lesions were distinct in edema level and vascularity patterns on CT and MRI. However, pathological examination of brain biopsy specimens revealed commonalities, including (1) proliferation of glial cells, (2) perivascular lymphocytic infiltration, and (3) appearance of numerous macrophages. Although atypical astrocytes proliferated in both cases, nuclear atypia was more distinct in case 2 than in case 1. The immunohistochemical results were the same for both cases: isocitrate dehydrogenase 1 (IDH1) R132H mutation was negative, and alpha thalassaemia mental retardation X-linked (ATRX) was retained. Faint immunoreactivity for p53 was observed in a few glial cells, and Ki-67 immunoreactive cells were markedly reduced in numbers (< 1%). Inflammatory reactions were evident in both cases: T cells dominantly infiltrated over B cells in the perivascular area in case 1, whereas both T and B cells infiltrated in case 2. Molecular analysis revealed wild-type IDH1 and IDH2 in both cases. However, a telomerase reverse transcriptase (TERT) sequence mutation was detected in case 2 but not in case 1. Eventually, case 1 was diagnosed as having inflammatory lesions, whereas case 2 was diagnosed as having diffuse astrocytoma associated with inflammatory reactions. The prognosis was favorable for case 1, whereas case 2 died 10 months following biopsy. These data indicated the diagnostic value of molecular analysis, for example, a TERT mutation, in association with the radiological findings. Although in case 2, histopathological evidence did not suggest high-grade glioma, the case met the new diagnostic criteria: "diffuse astrocytic glioma, IDH wild-type, with molecular features of glioblastoma, World Health Organization (WHO) grade IV," according to cIMPACT-NOW, update 3. Thus, interdisciplinary approaches are essential for accurate diagnosis of newly categorized white matter diseases.


Assuntos
Astrocitoma , Neoplasias Encefálicas , Substância Branca , Astrocitoma/diagnóstico por imagem , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Humanos , Inflamação , Isocitrato Desidrogenase/genética , Mutação , Substância Branca/diagnóstico por imagem
3.
No Shinkei Geka ; 48(8): 701-706, 2020 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-32830134

RESUMO

A 60-year-old woman was referred to our hospital because of possible miliary brain metastases of unknown primary origin. On admission, she was alert and had no apparent motor weakness. Neuroradiological examinations revealed more than 100 small enhancing lesions, some of which had undergone cystic changes, suggesting multiple metastases. However, plain chest and abdominal CT revealed no abnormalities, and fluorodeoxyglucose-positron emission tomography could not reveal the primary origin of the cancer. Blood examination revealed no apparent abnormalities, except for tumor markers, including pro-gastrin-releasing peptide and carcinoembryonic antigen. On day 22, the patient underwent a biopsy through right frontal craniotomy. Histopathological findings indicated metastases from cancer. Immunohistochemistry was positive for cytokeratin(CK)7 and thyroid transcription factor-1 while negative for CK20(-), CK5/6, and p40, resulting in the diagnosis of lung adenocarcinoma. Genetic testing showed negative for EGFR mutation and positive for ALK fusion gene. From the day 48, whole brain radiotherapy was started, and the ALK inhibitor was prescribed from day 64. Metastatic brain tumors of unknown primary are rare. Miliary brain metastases from an unknown primary origin are rare. To our knowledge, this is the first case of military brain metastases of an unknown primary origin, which was later determined to have originated from ALK fusion-positive lung cancer.


Assuntos
Adenocarcinoma de Pulmão , Adenocarcinoma , Neoplasias Encefálicas , Neoplasias Pulmonares , Biomarcadores Tumorais , Feminino , Humanos , Pessoa de Meia-Idade
4.
Cell Physiol Biochem ; 46(1): 57-68, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29587284

RESUMO

BACKGROUND/AIMS: Bone marrow stromal cells (BMSCs) transplantation is an important strategy for the treatment of ischemic stroke. Currently, there are no effective methods to guide BMSCs toward the targeted site. In this study, we investigated the effect of electrical stimulation on BMSCs migration in an ischemic model of rats. METHODS: Adult male Wistar rats weighing 200 to 250 g received right middle cerebral artery occlusion (MCAO) for 90 minutes. BMSCs (2.5×105 cells/ 4 µl PBS) were stereotaxically injected into the left corpus callosum at 1 day after MCAO. After BMSCs injection, a plate electrode with a diameter of 3 mm connected to an implantable electrical stimulator was placed on the right frontal epidural space and a counter electrode was placed in the extra-cranial space. Electrical stimulation at preset current (100 µA) and frequency (100 Hz) was performed for two weeks. Behavioral tests were performed at 1, 4, 8, and 15 days after MCAO using the modified Neurological Severity Score (mNSS) and cylinder test. Rats were euthanized at 15 days after MCAO for evaluation of infarction area and the migration distance and area of BMSCs found in the brain tissue. After evaluating cell migration, we proceeded to explore the mechanisms guiding these observations. MCAO rats without BMSCs transplantation were stimulated with same current and frequency. At 1 and 2 weeks after MCAO, rats were euthanized to evaluate stromal cell-derived factor 1 alpha (SDF-1α) level of brain tissues in the bilateral cortex and striatum. RESULTS: Behavioral tests at 4, 8, and 15 days after MCAO revealed that stimulation group displayed significant amelioration in mNSS and cylinder test compared to control group (p<0.05). Similarly, the infarction areas of stroke rats in stimulation group were significantly decreased compared to control group (p<0.05). Migration distance and area of transplanted BMSCs were significantly longer and wider respectively in stimulation group. An increased concentration gradient of SDF-1α in stimulation group accompanied this enhanced migration of transplanted cells. CONCLUSIONS: These results suggest that electrical stimulation enhances migratory ability of transplanted BMSCs in ischemic stroke model of rats. If we can direct the implanted BMSCs to the site of interest, it may lead to a greater therapeutic effect.


Assuntos
Transplante de Células-Tronco Mesenquimais , Acidente Vascular Cerebral/prevenção & controle , Animais , Comportamento Animal , Peso Corporal , Células da Medula Óssea/citologia , Encéfalo/patologia , Isquemia Encefálica/etiologia , Movimento Celular , Células Cultivadas , Quimiocina CXCL12/análise , Quimiocina CXCL12/metabolismo , Estimulação Elétrica , Ensaio de Imunoadsorção Enzimática , Infarto da Artéria Cerebral Média/complicações , Masculino , Células-Tronco Mesenquimais/citologia , Ratos , Ratos Wistar , Receptores CXCR4/metabolismo , Acidente Vascular Cerebral/patologia
5.
Int J Mol Sci ; 14(11): 21513-24, 2013 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-24177570

RESUMO

The number of diabetes mellitus (DM) patients is increasing, and stroke is deeply associated with DM. Recently, neuroprotective effects of glucagon-like peptide-1 (GLP-1) are reported. In this study, we explored whether liraglutide, a GLP-1 analogue exerts therapeutic effects on a rat stroke model. Wistar rats received occlusion of the middle cerebral artery for 90 min. At one hour after reperfusion, liraglutide or saline was administered intraperitoneally. Modified Bederson's test was performed at 1 and 24 h and, subsequently, rats were euthanized for histological investigation. Peripheral blood was obtained for measurement of blood glucose level and evaluation of oxidative stress. Brain tissues were collected to evaluate the level of vascular endothelial growth factor (VEGF). The behavioral scores of liraglutide-treated rats were significantly better than those of control rats. Infarct volumes of liraglutide-treated rats at were reduced, compared with those of control rats. The level of derivatives of reactive oxygen metabolite was lower in liraglutide-treated rats. VEGF level of liraglutide-treated rats in the cortex, but not in the striatum significantly increased, compared to that of control rats. In conclusion, this is the first study to demonstrate neuroprotective effects of liraglutide on cerebral ischemia through anti-oxidative effects and VEGF upregulation.


Assuntos
Complicações do Diabetes/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Acidente Vascular Cerebral/tratamento farmacológico , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Glicemia , Complicações do Diabetes/metabolismo , Complicações do Diabetes/patologia , Modelos Animais de Doenças , Peptídeo 1 Semelhante ao Glucagon/administração & dosagem , Humanos , Infarto da Artéria Cerebral Média , Liraglutida , Fármacos Neuroprotetores/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Ratos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia
6.
No Shinkei Geka ; 41(1): 53-7, 2013 Jan.
Artigo em Japonês | MEDLINE | ID: mdl-23269256

RESUMO

An aneurysm arising in the distal anterior cerebral artery (DACA) is relatively rare. Among them, those in the non-branching segment are seldom reported so far. The authors present the case of an 87-year-old woman who developed intracerebral hemorrhage and acute hydrocephalus due to rupture of an aneurysm arising in the non-branching site of DACA. External ventricular drainage followed by aneurysm clipping by bifrontal craniotomy was performed as treatment. Microscopic observations revealed that the aneurysm was saccular-shaped, located at the non-branching site of the A3 portion of the anterior cerebral artery, and had significant atherosclerosis neither on its parent artery nor neck. Histopathological examinations of the aneurysm wall denied traumatic aneurysm or mycotic aneurysm, and showed partial disruption of the internal elastic lamina, suggesting a difference from common aneurysms arising at arterial branchings. Profound knowledge of this type of aneurysms would be useful in dealing with them at surgery.


Assuntos
Aneurisma/cirurgia , Artéria Cerebral Anterior/patologia , Artéria Cerebral Anterior/cirurgia , Hemorragia Cerebral/cirurgia , Idoso de 80 Anos ou mais , Angiografia Cerebral/métodos , Craniotomia/métodos , Feminino , Humanos , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
NMC Case Rep J ; 10: 131-137, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37293194

RESUMO

Eating disorders caused by brain tumors are infrequently seen. Recent studies revealed that a neurocircuit from the nucleus tractus solitarius of the medulla oblongata to the hypothalamus participates in the control of appetite. Among brain tumors, those located in the brain stem, especially a solitary one in the medulla oblongata, are rare. Tumors in the brainstem are generally considered gliomas, and with the difficulty in reaching the lesion, treatment without histological confirmation is often performed. However, there are a few reported cases of medulla oblongata tumors other than gliomas. We describe a case of a 56-year-old man who presented with persistent anorexia. Magnetic resonance images revealed a solitary tumor in the medulla oblongata. After several examinations, craniotomy for the biopsy of the tumor using the cerebellomedullary fissure approach was carried out and primary central nervous system lymphoma (PCNSL) was histologically proven. The patient was treated with effective adjuvant therapy and was discharged home after he recovered from the symptoms. No tumor recurrence was recognized 24 months after surgery. A PCNSL arising only from the medulla oblongata is very rare, and anorexia can be an initial symptom of a tumor in the medulla oblongata. Surgical intervention is safely achieved and is a key to a better clinical outcome.

8.
Neurol Med Chir (Tokyo) ; 63(11): 495-502, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37853615

RESUMO

Primary central nervous system lymphoma (PCNSL), a relatively rare brain tumor, bears a dire prognosis. On occasion, the rapid progression of the tumor makes immediate diagnosis and initiation of therapy imperative. To achieve swift diagnosis, we adopt flow cytometry (FCM) in addition to conventional histopathology. This study aimed to reveal the utility of FCM diagnosis for PCNSL and the cause of false-negative results of FCM diagnosis. We investigated 33 patients with suspected PCNSL on neuroradiological findings and received both FCM and histological diagnosis. The patients' electronic medical records were investigated, and histological findings, results of FCM, and other clinical data were evaluated. Overall, 27 patients (14 males and 13 females) were diagnosed with PCNSL by histological confirmation. The median age at diagnosis was 68 years. FCM analysis showed lymphoma pattern in 24 cases; however, FCM results did not show lymphoma pattern (sensitivity: 88.9%, specificity: 100%) in the other three lymphoma cases (FCM discordant: FCM-D) and six nonlymphomatous tumor cases. Analysis of FCM-D cases showed the infiltration of T lymphocytes or astrocytes into the tumor tissue, indicating tumor microenvironmental reaction; it is assumed that these reactions deceived FCM diagnosis. The survival of FCM-D patients was superior to FCM concordant counterpart, although the difference was not significant (p = 0.459). The diagnosis of PCNSL by FCM is rapid and highly reliable. Some FCM-D cases are PCNSLs with strong tumor microenvironmental reactions.


Assuntos
Neoplasias Encefálicas , Neoplasias do Sistema Nervoso Central , Linfoma , Masculino , Feminino , Humanos , Idoso , Citometria de Fluxo/métodos , Linfoma/diagnóstico , Neoplasias Encefálicas/diagnóstico , Prognóstico , Sistema Nervoso Central , Neoplasias do Sistema Nervoso Central/diagnóstico
9.
J Neuroimmunol ; 365: 577823, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35158108

RESUMO

We present the case of a 52-year-old woman with right hemiparesis due to a mass lesion in the left parietal white matter and corpus callosum. The lesion was hyperintense on diffusion weighted image and homogenously enhanced with gadolinium on magnetic resonance imaging, and was radiologically indistinguishable with lymphoma. Following progressive aggravation of symptoms, craniotomy for biopsy of the lesion was performed, and it was revealed that the patient had anti-myelin oligodendrocyte glycoprotein-associated disease by histopathological and serological diagnosis. Initial treatment with steroid dramatically improved the symptoms, but they exacerbated again. Then, through cerebrospinal fluid examination, it was revealed that the patient had B-cell lymphoma.


Assuntos
Autoanticorpos , Linfoma de Células B , Sistema Nervoso Central , Feminino , Humanos , Linfoma de Células B/diagnóstico , Linfoma de Células B/diagnóstico por imagem , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Glicoproteína Mielina-Oligodendrócito
10.
NMC Case Rep J ; 9: 199-208, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35974956

RESUMO

Despite recent signs of progress in diagnostic radiology, it is quite rare that a glioblastoma (GBM) is detected asymptomatically. We describe two patients with asymptomatic nonenhancing GBMs that were not diagnosed with neoplasia at first. The patients had brain scans as medical checkups, and incidentally lesions were detected. In both cases, surgical specimens histopathologically showed no evidence of neoplasia, whereas molecular genetic findings were isocitrate dehydrogenase (IDH)-wildtype, O6-methylguanine-DNA methyltransferase promoter (pMGMT) unmethylated, and telomerase reverse transcriptase (TERT) promoter mutated, which matched to GBM. One patient was observed without adjuvant therapy and the tumor recurred 7 months later. Reoperation was performed, and histopathologically GBM was confirmed with the same molecular diagnosis as the first surgical specimen. Another patient was carefully observed, and chemoradiotherapy was begun 6 months after the operation following the extension of the lesion. Eventually, because of disease progression, both patients deceased. We postulate that in each case, the tumor was not lower-grade glioma but corresponded to the early growth phase of GBM cells. Thus far, cases of malignant transformation from lower-grade glioma or asymptomatic GBM with typical histologic features are reported. Nevertheless, to the best of our knowledge, no such case of nonenhancing, nonhistologically confirmed GBM was reported. We conjecture these cases shed light on the yet unknown natural history of GBM. GBM can take the form of radiological nonenhancing and histological nonneoplastic fashion before typical morphology. Molecular genetic analysis can diagnose atypical preceding GBM, and we recommend early surgical removal and adjuvant treatment.

11.
J Agric Food Chem ; 69(44): 13190-13199, 2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34723485

RESUMO

The metabolic fate of a newly developed herbicide, epyrifenacil, (ethyl[(3-{2-chloro-4-fluoro-5-[3-methyl-2,6-dioxo-4-(trifluoromethyl)-3,6-dihydropyrimidin-1(2H)-yl]phenoxy}pyridin-2-yl)oxy]acetate, S-3100), in rats was determined using 14C-labeled epyrifenacil. When it was administered orally to rats at 1 mg/kg, around 73-74% of the dose was absorbed, metabolized, and mainly excreted into feces within 48 h. The elimination of radioactivity in plasma and tissues was rapid, suggesting that exposure of epyrifenacil and metabolites is small. Metabolite analysis revealed that epyrifenacil was rapidly ester-cleaved to M1 and then mainly excreted into bile or further metabolized. No parent was detected in plasma, tissues, and urine. Remarkably, M1 was mainly distributed in the liver (at a concentration of 70-112 times higher than in plasma at a low dose). Furthermore, a significant sex-related difference was observed in urinary excretion of M1. Considering the above observations with those in the literature, the organic anion-transporting polypeptide (OATP) likely plays a role on the active transport of M1 in the liver and kidney.


Assuntos
Líquidos Corporais , Herbicidas , Administração Oral , Animais , Bile , Fezes , Ratos , Distribuição Tecidual
12.
J Pestic Sci ; 46(4): 333-341, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34908893

RESUMO

A new herbicide, epyrifenacil (S-3100), inhibits protoporphyrinogen oxidase (PPO) in plants. Repeated administration of epyrifenacil in laboratory animals led to some toxicological changes related to PPO inhibition, e.g., hepatotoxicity caused by porphyrin accumulation and anemia caused by the inhibition of heme biosynthesis. In vitro studies revealed that an ester-cleaved metabolite, S-3100-CA, is predominant in mammals, exhibits PPO-inhibitory activity, and thus is the cause of epyrifenacil-induced toxicity. To assess the human risk, the effects of species differences on the dynamics (PPO inhibition) and kinetics (liver uptake) of epyrifenacil were evaluated separately. The results of in vitro assays revealed an approximately tenfold weaker inhibition of PPO by S-3100-CA in humans than in rodents and six- to thirteen-fold less hepatic uptake of S-3100-CA in humans than in mice. Finally, it was suggested that humans are less sensitive to the toxicity of epyrifenacil than are rodents, although further mechanistic research is highly anticipated.

13.
Cancer Gene Ther ; 28(12): 1339-1352, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33414520

RESUMO

The prognosis of glioblastoma remains poor despite intensive research efforts. Glioblastoma stem cells (GSCs) contribute to tumorigenesis, invasive capacity, and therapy resistance. Leucine-rich repeat-containing G-protein coupled receptor 5 (Lgr5), a stem cell marker, is involved in the maintenance of GSCs, although the properties of Lgr5-positive GSCs remain unclear. Here, the Sleeping-Beauty transposon-induced glioblastoma model was used in Lgr5-GFP knock-in mice identify GFP-positive cells in neurosphere cultures from mouse glioblastoma tissues. Global gene expression analysis showed that Gli2 was highly expressed in GFP-positive GSCs. Gli2 knockdown using lentiviral-mediated shRNA downregulated Hedgehog-related and Wnt signaling pathway-related genes, including Lgr5; suppressed tumor cell proliferation and invasion capacity; and induced apoptosis. Pharmacological Gli inhibition with GANT61 suppressed tumor cell proliferation. Silencing Gli2 suppressed the tumorigenicity of GSCs in an orthotopic transplantation model in vivo. These findings suggest that Gli2 affects the Hedgehog and Wnt pathways and plays an important role in GSC maintenance, suggesting Gli2 as a therapeutic target for glioblastoma treatment.


Assuntos
Neoplasias Encefálicas/genética , Perfilação da Expressão Gênica/métodos , Glioblastoma/genética , Proteína Gli2 com Dedos de Zinco/metabolismo , Animais , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Modelos Animais de Doenças , Glioblastoma/patologia , Humanos , Camundongos , Prognóstico
14.
World Neurosurg ; 134: 472-476, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31756510

RESUMO

BACKGROUND: Spinal subdural hematoma (SSDH), which can cause lower back pain, leg pain, and leg weakness, is rare and will usually be associated with a bleeding tendency, trauma, spinal vascular malformation, intraspinal tumor, or iatrogenic invasion. Only a few cases of SSDH after intracranial chronic subdural hematoma (CSDH) have been reported. We report a case of lumbar SSDH in the absence of predisposing factors after reoperation for recurrent intracranial CSDH, which improved with conservative treatment. CASE DESCRIPTION: Approximately 1 month after falling, a 63-year-old woman was experiencing left hemiparesis and impaired orientation that was diagnosed as right intracranial CSDH using computed tomography. Surgical treatment of the CSDH led to immediate improvement of her symptoms. On postoperative day 29, the right CSDH had recurred with left hemiparesis, and successful reoperation relieved the symptoms within a few hours postoperatively. However, 1 day after the second operation, very small acute subdural hematomas in regions along the left tentorium cerebelli and left falx cerebri were found on computed tomography. On day 31, she complained of sitting-induced bilateral radiating lower limb pain. Magnetic resonance imaging on day 34 showed an acute SSDH at the L4-L5 level and a sacral perineural cyst filled with hematoma, although her radiating pain was showing improvement. She was treated conservatively and was discharged without symptoms on day 44. CONCLUSIONS: Although SSDH is rare, it is important for neurosurgeons and physicians to consider the possibility of a SSDH when lower limb pain or paresis occurs after procedures that will result in rapid intracranial pressure alterations such as drainage of an intracranial CSDH.


Assuntos
Hematoma Subdural Crônico/complicações , Hematoma Subdural Intracraniano/complicações , Hematoma Subdural Espinal/complicações , Hematoma Subdural Espinal/patologia , Feminino , Hematoma Subdural Crônico/patologia , Hematoma Subdural Crônico/cirurgia , Hematoma Subdural Intracraniano/patologia , Hematoma Subdural Intracraniano/cirurgia , Humanos , Região Lombossacral , Pessoa de Meia-Idade , Recidiva , Reoperação
15.
Front Aging Neurosci ; 10: 29, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29527162

RESUMO

Several reports have shown that long-term potentiation (LTP) per se effectively enhances neurogenesis in the hippocampus of intact animals. If LTP can enhance neurogenesis in chronic hypoperfusion, this approach could potentially become a new therapeutic strategy for the restoration of cognitive function and for prevention from deterioration of mild cognitive impairment (MCI). Using an in vivo LTP model of rats, we examined whether LTP per se can enhance neurogenesis in hypoperfusion rats that underwent permanent bilateral common carotid artery occlusion (permanent 2-vessel occlusion, P2VO). High frequency stimulation (HFS) in the subacute phase after P2VO enhanced hippocampal cell proliferation and neurogenesis. However, most enhanced cell proliferation and neurogenesis was seen in the hypoperfusion rats that received HFS and for which LTP could finally be induced. In contrast, the same effect was not seen in the LTP induction in the chronic phase. The present findings, which reveal that most enhanced neurogenesis was seen in hypoperfusion rats for which LTP could be finally induced, could explain the ability of LTP-like activities such as learning paradigms and environmental stimuli to increase the rate of neurogenesis in the hippocampus even under hypoperfusion conditions. Moreover, the present findings, which reveal that LTP induction in the chronic phase after P2VO could not effectively enhance neurogenesis in the hypoperfusion rats, could indicate that patients with MCI and even middle-aged healthy control individuals should start LTP-like activities as early as possible and continue with these activities to prevent age-related deterioration of hippocampal function.

16.
No Shinkei Geka ; 35(5): 489-93, 2007 May.
Artigo em Japonês | MEDLINE | ID: mdl-17491345

RESUMO

Cerebral amyloid angiopathy (CAA), in which deposition of amyloid within the arterial media and adventitia is the remarkable feature, causes spontaneous lober cerebral hemorrhage in elderly person, and some reports show the quite high occurrence rate of this entity among intracerebral hemorrhage in patents above 70 years old. Brain abscess resulting from intracerebral hemorrhage is rare. To our knowledge, no report of such hemorrhage which is caused by CAA has been published so far. We report a case of brain abscess, from which Stenotrophomonas maltophilia was isolated, following spontaneous non-hypertensive intracerebral hemorrhage caused by probable CAA, with a review of the relevant literature.


Assuntos
Abscesso Encefálico/etiologia , Angiopatia Amiloide Cerebral/complicações , Hemorragia Cerebral/complicações , Infecções por Bactérias Gram-Negativas , Stenotrophomonas maltophilia , Idoso , Angiopatia Amiloide Cerebral/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico por imagem , Humanos , Masculino , Tomografia Computadorizada por Raios X
17.
Cancer Res ; 65(8): 3336-46, 2005 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15833867

RESUMO

The mammalian target of rapamycin (mTOR) is a downstream effector of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway and a central modulator of cell proliferation in malignant gliomas. Therefore, the targeting of mTOR signaling is considered a promising therapy for malignant gliomas. However, the mechanisms underlying the cytotoxic effects of a selective mTOR inhibitor, rapamycin, on malignant glioma cells are poorly understood. The purpose of this study was thus to elucidate how rapamycin exerts its cytotoxic effects on malignant glioma cells. We showed that rapamycin induced autophagy but not apoptosis in rapamycin-sensitive malignant glioma U87-MG and T98G cells by inhibiting the function of mTOR. In contrast, in rapamycin-resistant U373-MG cells, the inhibitory effect of rapamycin was minor, although the phosphorylation of p70S6 kinase, a molecule downstream of mTOR, was remarkably inhibited. Interestingly, a PI3K inhibitor, LY294002, and an Akt inhibitor, UCN-01 (7-hydroxystaurosporine), both synergistically sensitized U87-MG and T98G cells as well as U373-MG cells to rapamycin by stimulating the induction of autophagy. Enforced expression of active Akt in tumor cells suppressed the combined effects of LY294002 or UCN-01, whereas dominant-negative Akt expression was sufficient to increase the sensitivity of tumor cells to rapamycin. These results indicate that rapamycin exerts its antitumor effect on malignant glioma cells by inducing autophagy and suggest that in malignant glioma cells a disruption of the PI3K/Akt signaling pathway could greatly enhance the effectiveness of mTOR inhibitors.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Inibidores Enzimáticos/farmacologia , Glioma/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Sirolimo/farmacologia , Estaurosporina/análogos & derivados , Antibióticos Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Linhagem Celular Tumoral , Cromonas/administração & dosagem , Sinergismo Farmacológico , Inibidores Enzimáticos/administração & dosagem , Glioma/enzimologia , Glioma/patologia , Humanos , Morfolinas/administração & dosagem , Inibidores de Proteínas Quinases/farmacologia , Proteínas Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt , Sirolimo/administração & dosagem , Estaurosporina/administração & dosagem , Serina-Treonina Quinases TOR
18.
Neurol Med Chir (Tokyo) ; 57(3): 115-121, 2017 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-28154342

RESUMO

A significant controversy exists regarding the clinical impact of hemodynamic depression on major adverse events after carotid artery stenting (CAS). The purpose of this study was to evaluate the incidence, predictors, and clinical significance of hypotension after CAS. A total of 118 cases of carotid artery stenosis were treated with CAS. Hypotension was defined as sustained systolic blood pressure <80 mmHg and requiring intravenous administration of vasopressor to maintain adequate systolic blood pressure after the procedure. Baseline characteristics, procedural characteristics, and periprocedural major adverse events were retrospectively compared between postprocedural hypotension group and non-hypotension group. Morphological and procedural characteristics were not significantly different between the two groups. Periprocedural major adverse events, presence of new ischemic lesions, and number of new ischemic lesions were not significantly different between the two groups (P = 1, P = 0.36, P = 0.68). Hypertension was an independent protective factor (P = 0.037), and use of proximal protection and the distance from carotid bifurcation to maximum stenotic lesion ≤ 10 mm were independent risk factors for developing hypotension after CAS (P = 0.034, P = 0.027). There was no significant relationship between hypotension after CAS and major adverse events in this study. Maintenance of periprocedural adequate cerebral perfusion is thought to be important to prevent ischemic complications due to hypotension after CAS, especially in these cases.


Assuntos
Estenose das Carótidas/terapia , Procedimentos Endovasculares/efeitos adversos , Hipotensão/tratamento farmacológico , Complicações Pós-Operatórias/tratamento farmacológico , Stents , Vasoconstritores/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Hipotensão/diagnóstico , Hipotensão/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Fatores de Risco
19.
Cancer Res ; 64(12): 4286-93, 2004 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-15205343

RESUMO

The sphingolipid ceramide has been recognized as an important second messenger implicated in regulating diverse signaling pathways especially for apoptosis. Very little is known, however, about the molecular mechanisms underlying nonapoptotic cell death induced by ceramide. In the present study, we first demonstrate that ceramide induces nonapoptotic cell death in malignant glioma cells. The cell death was accompanied by several specific features characteristic of autophagy: presence of numerous autophagic vacuoles in the cytoplasm, development of the acidic vesicular organelles, autophagosome membrane association of microtubule-associated protein light chain 3 (LC3), and a marked increase in expression levels of two forms of LC3 protein (LC3-I and LC3-II). We additionally demonstrate that ceramide decreases mitochondrial membrane potential and activates the transcription of death-inducing mitochondrial protein, BNIP3, resulting in increased expression levels of its mRNA and protein in malignant glioma cells. Moreover, tumor cells transfected with BNIP3 gene undergo autophagy in the absence of ceramide. These results suggest that ceramide induces autophagic cell death in malignant glioma cells via activation of BNIP3. This study adds a new concept to characterize the pathways by which ceramide acts to induce nonapoptotic autophagic cell death in malignant gliomas.


Assuntos
Glioma/patologia , Proteínas de Membrana/fisiologia , Proteínas Proto-Oncogênicas/fisiologia , Esfingosina/análogos & derivados , Esfingosina/farmacologia , Autofagia/efeitos dos fármacos , Autofagia/fisiologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular Tumoral , Fase G2/efeitos dos fármacos , Fase G2/fisiologia , Glioma/tratamento farmacológico , Glioma/genética , Glioma/metabolismo , Humanos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/fisiologia , Potenciais da Membrana/efeitos dos fármacos , Proteínas de Membrana/biossíntese , Proteínas de Membrana/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Mitose/efeitos dos fármacos , Mitose/fisiologia , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , Transfecção
20.
World Neurosurg ; 91: 308-16, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27072330

RESUMO

OBJECTIVE: Reducing complications from unruptured aneurysms (UAs) treatment is important. We clarify the criteria for achieving safe and complete treatment for UAs ≤10 mm by clipping or coil embolization. METHODS: This study included 59 newly treated UAs in the past 2 years. We prospectively decided on criteria to recommend active treatment. UAs ≤10 mm and in ≤75 year-olds, located at in the internal carotid artery at the paraclinoid portion and the posterior circulation aneurysms except for a vertebral artery-inferior posterior cerebellar artery aneurysm were mainly treated by coil embolization, and those in the internal carotid artery except at the paraclinoid portion, in the anterior or middle cerebral artery, and in the vertebral artery-inferior posterior cerebellar artery were treated preferably by clipping. UAs with a height/neck ratio or a dome/neck ratio ≤1.4 were treated preferentially by clipping. Specific preoperative imaging and careful manipulation were adopted for clipping. RESULTS: Fifty-seven (96.6%) achieved modified Rankin scale (mRS) 0-1, 2 (3.4%) mRS 2-5, and 0 had mRS 6. Fifty-three UAs (89.8%) achieved complete occlusion (CO) and 7 (10.1%) had neck remnants (NR). Forty-one UAs (100%) within the criteria achieved mRS 0-1, 40 (98%) achieved CO, and 1 (2%) NR. The odds ratio of NR for those outside the criteria was 18.5 (95% confidence interval, 1.83-186.6) (P < 0.05). CO treated within the criteria was 39 and NR was 1. CO treated outside the criteria was 14 and NR was 5 (P < 0.05). The mRS 0-1 with age ≤75 years was 55 and the mRS 2-6 was 0. The mRS 0-1 with age ≥76 years was 2 and the mRS 2-6 was 2 (P < 0.01). CONCLUSIONS: The treatment for UAs within the criteria, with the most recent points of concern, can lead to safe and complete results.


Assuntos
Embolização Terapêutica/métodos , Aneurisma Intracraniano/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Oclusão com Balão/métodos , Angiografia por Tomografia Computadorizada/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
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