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1.
J Cell Sci ; 134(5)2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32482793

RESUMO

Foot-and-mouth disease virus (FMDV) is a picornavirus that causes contagious acute infection in cloven-hoofed animals. FMDV replication-associated viral protein expression induces endoplasmic reticulum (ER) stress and the unfolded protein response (UPR), in turn inducing autophagy to restore cellular homeostasis. We observed that inhibition of BiP (also known as HSPA5 and GRP78), a master regulator of ER stress and UPR, decreased FMDV infection confirming their involvement. Further, we show that the FMDV infection induces UPR mainly through the PKR-like ER kinase (PERK; also known as EIF2AK3)-mediated pathway. Knockdown of PERK and chemical inhibition of PERK activation resulted in decreased expression of FMDV proteins along with the reduction of autophagy marker protein LC3B-II [the lipidated form of LC3B (also known as MAP1LC3B)]. There are conflicting reports on the role of autophagy in FMDV multiplication. Our study systematically demonstrates that during FMDV infection, PERK-mediated UPR stimulated an increased level of endogenous LC3B-II and turnover of SQSTM1, thus confirming the activation of functional autophagy. Modulation of the UPR and autophagy by pharmacological and genetic approaches resulted in reduced numbers of viral progeny, by enhancing the antiviral interferon response. Taken together, this study underscores the prospect of exploring PERK-mediated autophagy as an antiviral target.


Assuntos
Vírus da Febre Aftosa , Animais , Antivirais/farmacologia , Autofagia , Estresse do Retículo Endoplasmático , Vírus da Febre Aftosa/metabolismo , Interferons , Resposta a Proteínas não Dobradas , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
2.
Electrophoresis ; 40(7): 1066-1073, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30632171

RESUMO

A simple, sensitive, and stability indicating isocratic reverse phase high performance liquid chromatography method has been developed, optimized and validated for the separation and quantification of S-enantiomer in linagliptin (R-enantiomer) drug substance. Enantiomeric separation was achieved on a Cellulose tris(4-chloro-3-methylphenylcarbamate) stationary phase. Mobile phase consists of aqueous diammonium hydrogen phosphate buffer and acetonitrile in the ratio of 35:65 v/v. Isocratic elution was performed at a flow rate of 1.0 mL/min, the column oven temperature was set at 40°C and detection was at 226 nm. The resolution between R and S enantiomers is found to be more than 4.0. The impact of mobile phase composition, pH of buffer and temperature on the resolution has been studied. The detector response is found to be linear over the concentration range of 0.17-1.7 µg/mL. LOD and LOQ levels of S-enantiomer are found to be 0.057 and 0.172 µg/mL respectively. The recovery of S-enantiomer is 99.8% w/w. The proposed method is validated for specificity, precision, linearity, accuracy and robustness.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia de Fase Reversa/métodos , Inibidores da Dipeptidil Peptidase IV/análise , Linagliptina/análise , Acetonitrilas/química , Celulose/química , Limite de Detecção , Fosfatos/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estereoisomerismo , Temperatura
3.
Metab Brain Dis ; 34(1): 103-117, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30284105

RESUMO

It is frequently accepted that grape seed proanthocyanidins (GSPs) are efficient antioxidants and beneficial in improving cognitive functions. However, diabetes (T1DM)-associated declines in learning and memory and the possibilities of GSPs in overcoming this loss needs to be examined. The present study was designed to examine the correlation, if one exists, between cognitive behavior and neuronal survival in the prefrontal cortex (PFC) in streptozotocin (STZ)-induced diabetic Wistar rats as well as to further clarify whether the correlation exists. Also this study aimed to determine whether neurological structural changes in the PFC and pancreatic ß-cells can be restored by grape seed proanthocyanidin extract (GSPE). At the end of 8 weeks, cognitive tests that rats given supplementation of GSPE and insulin had greater improvement in their spatial learning and memory skills and improved neuronal survival in the PFC and pancreatic ß-cells compared to rats supplemented with either insulin or GSPE alone. Expression of Bax in the PFC was increased in the diabetic rats while Bcl-2 expression was decreased, and GSPE and insulin treatment reversed the expression of apoptotic proteins. Our findings on GSPE, a natural product, as a form of adjuvant therapy together with insulin treatment is suggestive of the existence of synergism between the two in attenuating diabetic complications in the pancreas and PFC.


Assuntos
Disfunção Cognitiva/prevenção & controle , Diabetes Mellitus Tipo 1/complicações , Extrato de Sementes de Uva/uso terapêutico , Insulina/uso terapêutico , Córtex Pré-Frontal/efeitos dos fármacos , Proantocianidinas/uso terapêutico , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína X Associada a bcl-2/metabolismo , Animais , Apoptose/efeitos dos fármacos , Glicemia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Extrato de Sementes de Uva/farmacologia , Insulina/farmacologia , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Córtex Pré-Frontal/metabolismo , Proantocianidinas/farmacologia , Ratos , Ratos Wistar , Aprendizagem Espacial/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos
4.
Neurol Sci ; 39(11): 1895-1902, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30090984

RESUMO

Astrocytoma is recognized as the most common neoplasm of the brain with aggressive progression. The therapeutic regime for glioblastoma, the most aggressive astrocytoma, often consists of aggressive chemo and radiotherapy. The present holistic approaches, however, have failed to influence the quality life of patients. Therefore, it is necessary to understand the underlying mechanisms of its progression for updated therapeutic evaluation. Human cytomegalovirus (HCMV) is reported to be associated with glioblastoma progression. The hypothesis still remains controversial due to the lack of concrete evidences. Here, we report the profile of miRNAs encoded by human host and the cytomegalovirus (CMV) involved in modulation of CMV infection in surgically resected human astrocytoma tissue samples of various malignancy grades (n = 24). Total RNA from the control brain and tumor tissues was extracted by TriZol reagent. The expression levels of the mature form of miRNA were detected by real-time PCR. Primarily, we found the upregulation of miR-210-3p, miR-155-5p, miR-UL-112-3p, miR-183-5p, and miR-223-5p in high-grade astrocytic tumors as compared with low-grade tumor tissues. miR-214-3p is significantly expressed in control brain tissues and its expression decreased with astrocytoma grade progression. This miRNA was reported to be associated with antiviral proprieties. Among CMV-encoded miRNA, miR-UL-112-3p was significantly upregulated in glioblastoma tissue samples and may be involved in providing immune escape to the virus as well as involved in modulating the immune microenvironment of glioblastoma. Taken together, we conclude the possible involvement of miRNAs in modulating the CMV dependent astrocytoma progression.


Assuntos
Astrocitoma/complicações , Neoplasias Encefálicas/complicações , Infecções por Citomegalovirus , Regulação Neoplásica da Expressão Gênica/fisiologia , MicroRNAs/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/virologia , Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/virologia , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , MicroRNAs/genética , RNA Mensageiro/metabolismo , Índice de Gravidade de Doença
5.
J ECT ; 30(3): 193-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24901429

RESUMO

Stress and depression are associated with impaired neuroplasticity in the hippocampus; there is a decrease in neurogenesis, which is hypothesized to decrease the adaptative competence of the organism. Representative light microscopy images are presented which show that 6 once-daily electroconvulsive shocks (ECS), dose-dependently increased new cell formation in the subgranular region of the hippocampus in healthy adult male Wistar rats (10 sections per rat, 3 rats in each of sham ECS, 10 mC, and 40 mC groups). These neuroplasticity changes, demonstrated 1 month after the last ECS, may explain a part of the mechanism of action of electroconvulsive therapy in conditions such as depression.


Assuntos
Eletroconvulsoterapia , Hipocampo/citologia , Hipocampo/ultraestrutura , Plasticidade Neuronal/fisiologia , Animais , Proliferação de Células , Masculino , Ratos , Ratos Wistar
6.
Cureus ; 16(5): e60895, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38836152

RESUMO

Background Of late, the interest in accelerated treatment protocols in repetitive transcranial magnetic stimulation (TMS) for the treatment of depression and obsessive-compulsive disorder (OCD) has been gaining momentum. Studies have already found that the patterned theta burst stimulation is non-inferior to the standard high-frequency stimulation in treating depression. The objective of the present study was to evaluate the clinical efficacy of a customized accelerated combination TMS naturalistic setting. Methods Retrospective analysis of pre and post-deep repetitive TMS responses in depression and OCD patients was performed. About 391 Depression and 239 OCD patients' data was analyzed. Customized treatment protocols consisted of twice daily high-frequency stimulations intervened by one theta burst stimulation. The outcome measures were a day six score in depression and a day 10 score in OCD, compared to day one baseline scores. Results The overall response rate in depression was 60.86%, estimated as a >50% reduction in the Hamilton Depression Rating Scale (HAM-D) 21 items score, and 62.76% in OCD, estimated as a >35% reduction in the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) score. The mean reduction of YBOCS and HAM-D was statistically significant at p<0.0001 (Mann-Whitney U test statistic=9442.5, z=12.66 for YBOCS and 16673.5, z=18.92 for HAM-D). Corresponding effect size estimations revealed Cohen's d value of 1.40 and 1.59, respectively. Conclusions The response rates achieved at day six and day 10 in depression and OCD, respectively, were comparable to previous studies employing standard treatment protocols. The accelerated protocol produced satisfactory short-term clinical outcomes that were effective in the early management of the illness without any serious adverse effects.

7.
J Med Phys ; 48(4): 345-349, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38223794

RESUMO

Aim: The aim of this study was to estimate the spinal column dose for spinal Stereotactic body radiation therapy (SBRT) before patient treatment using the PTW dosimetry Octavius dose-volume histograms (DVH) four-dimensional (4D) feature. Materials and Methods: Twenty-three patients were included in the study, and a volumetric modulated arc therapy plan with 6MV flattening filter-free (6FFF) was generated for each patient in the Eclipse planning system using the Anisotropic Analytical Algorithm (AAA) algorithm (Varian Medical Systems, Palo Alto, CA) for the TrueBeam STx LINAC machine. The Octavius 4D system was used to estimate the spinal cord dose by delivering the plans to the 4D phantom. The measured dose was compared with the Eclipse treatment planning system (TPS) (Varian Medical Systems, Palo Alto, CA) dose. Results: The spinal cord max and mean doses estimated using Varisoft DVH 4D are in close agreement with the TPS calculated max and mean doses. The deviation between measured dose and TPS dose is ±5% for the spinal max dose, and the deviation between measured dose and TPS dose is ± 3% for the spinal mean dose. Conclusions: The study demonstrates that the PTW Octavius 4D phantom and DVH 4D feature can be used as a tool to estimate spinal cord dose before the treatment in spinal SBRT plans. The system provides an independent dose measurement that is comparable to the TPS dose. The close agreement between measured and calculated doses validates the use of this system as a critical organ dose verification tool.

8.
Neurol India ; 69(4): 904-909, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34507410

RESUMO

BACKGROUND AND AIMS: Insular gliomas remain one of most challenging locations for aggressive resection. We report our experience and strategies we employed to avoid complications in immediate post-operative period of surgical resection of insular gliomas. METHODS: Retrospective analysis of data collected in 61 consecutive patients who underwent surgical resection of insular gliomas between May 2013 and May 2016 was done. Primary outcome measures were neurological deficits and death in the immediate post-operative period to three months follow-up. RESULTS: The average age of the study population was 42.57 ± 10.98 years with 41 (67.2%) men. Glioma was on the right side in 35 (57.3%) patients. Surgery for recurrent glioma was performed in three (4.9%) patients. The average MIB index of the entire group was 10.1 ± 13.9. While 23 (37.7%) patients underwent the TO approach, 38 (62.3%) underwent TS approach. In the immediate post-operative period, significantly higher number of patients under TS approach had post-surgical complications (8.6% vs 34.2%; P = 0.032). The surgical approaches did not differ significantly for outcome, mortality and complications at three month post-operatively (0.0% vs 10.5%; P = 0.287). However, a trend for lower complications at three months was observed with TO approach. CONCLUSION: We report that morbidity and mortality in immediate post-operative period can be reduced by: a) pre-surgical assessment of confinement of glioma in respect to lenticulo-striate arteries, b) Intra-operative use of functional-MRI, DTI tractography and ICG angiography, c) Application of Berger-Sinai classification to localize the glioma, d) selecting either TS or TO approach based on Berger-Sinai classification.


Assuntos
Neoplasias Encefálicas , Glioma , Cirurgiões , Adulto , Neoplasias Encefálicas/cirurgia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/cirurgia , Glioma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Procedimentos Neurocirúrgicos/efeitos adversos , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Resultado do Tratamento
9.
Int J Dermatol ; 60(10): 1179-1182, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33709389

RESUMO

There are several neurological diseases wherein skin biopsy is useful for diagnosis, even in the absence of skin involvement. Skin biopsy is especially relevant in diseases in which the metabolic error is unknown or has no available diagnostic biochemical test. Skin biopsy, being relatively noninvasive, obviates the need for an invasive procedure such as a brain biopsy. These disorders wherein skin biopsies are particularly useful include the progressive myoclonic epilepsies, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL), neuroaxonal dystrophy, and small fiber neuropathies (SFN). We review the role of skin biopsy in such conditions with notes on preferred sites and techniques.


Assuntos
CADASIL , Dermatopatias , Biópsia , Humanos , Imageamento por Ressonância Magnética , Pele , Dermatopatias/diagnóstico
10.
Indian J Surg Oncol ; 10(1): 55-60, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30948873

RESUMO

Astrocytoma constitutes the most noted malignancies of the central nervous system with worse clinical outcomes in grade IV astrocytoma or glioblastoma multiforme. Owing to poor clinical outcomes with existing therapeutic regime, there is a need to revisit the initial course of treatment. Statistical information of clinicopathological parameters could be used to understand the spread of disease and, in turn, to formulate updated treatment management. In the present study, we have seen anatomic distribution of astrocytoma subtypes in a group of 479 patients and correlated it with survival outcomes. Anatomic location was confirmed by MRI (magnetic resonance imaging) images. A registry of patients was maintained with clinicopathological details as tumor type, location, age/sex, and survival after surgery. We have observed overall survival particulars in patients diagnosed with astrocytoma. Our findings highlight that in total cases, tumor location was anatomically dominated by frontal and temporal lobes. Survival analysis in high-grade (grade III, p = 0.03; grade IV, p = 0.01) astrocytic tumors confirms poor outcomes with temporal, parietal, and occipital location as compared to frontal lobe. Overall survival study demonstrates glioblastoma multiforme (GBM) was associated with worse prognosis as compared to astrocytoma subtypes (p < 0.0001). In high-grade astrocytomas, anaplastic astrocytoma was found with 34 months of median survival age while 14 months in the case of patients with glioblastoma multiforme. In conclusion, we report dismal prognosis in parietal, temporal, and occipital lobes in grade II, grade III, and grade IV astrocytoma patients. Among astrocytoma subtypes, patients with glioblastoma multiforme were associated with worse survival outcomes. We uniquely feature the survival of astrocytoma patients for the first time and observe GBM patients have slightly longer survival.

11.
Microsc Res Tech ; 82(2): 122-127, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30575195

RESUMO

Drug-resistant tuberculosis is being increasingly recognized and is one among the leading cause of death worldwide. Remarkable impermeability of cell wall to antituberculous drugs protects the mycobacteria from drug action. The present study analyzed the cell wall thickness among first-line drug resistant and sensitive Mycobacterium tuberculosis (Mtb) isolated from cerebrospinal fluid by transmission electron microscopy (TEM). The average thickness of the cell wall of sensitive isolates was 13.60 ± 0.98 nm. The maximum difference (26.48%) in the cell wall thickness was seen among multi-drug resistant (18.50 ± 1.71 nm) isolates and the least difference (4.14%) was shown by streptomycin-resistant (14.18 ± 1.38 nm) isolates. The ultrastructural study showed evident differences in the cell wall thickness among sensitive and resistant isolates. Preliminary TEM examination of cells indicates that morphological changes occur in the cell wall which might be attributed to the drug resistance. The thickened wall of Mtb appears to help the bacilli to overcome the action of antituberculous drugs.


Assuntos
Parede Celular/ultraestrutura , Farmacorresistência Bacteriana , Mycobacterium tuberculosis/ultraestrutura , Antituberculosos/farmacologia , Biometria , Líquido Cefalorraquidiano/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Transmissão , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Meníngea/microbiologia
12.
J Pharm Biomed Anal ; 48(5): 1430-40, 2008 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-18947954

RESUMO

Several related substances (RS4-RS10) were detected in lopinavir drug substance at levels ranging from 0.03% to 0.1% by employing gradient RP-HPLC. The related substances were identified by LC-MS analysis. These related substances were isolated and characterized by Mass, (1)H NMR and FT-IR spectral data. The separation was achieved on a YMC Pack ODS-AQ (250 mm x 4.6 mm, 5 microm) column thermostated at 45 degrees C using 0.02 M KH(2)PO(4) (pH 2.5): acetonitrile as a mobile phase in gradient elution mode. A PDA detector set at 210 nm was used for detection. The investigated validation elements showed the method has acceptable specificity, accuracy, linearity, precision, robustness and high sensitivity with detection limits and quantitation limits ranging from 0.028 microg/ml to 0.063 microg/ml and 0.084 microg/ml to 0.192 microg/ml respectively. The method can be used for routine quality control analysis and stability testing of lopinavir drug substance.


Assuntos
Contaminação de Medicamentos , Inibidores da Protease de HIV/química , Preparações Farmacêuticas/química , Pirimidinonas/química , Soluções Tampão , Cromatografia Líquida de Alta Pressão/instrumentação , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Guias como Assunto , Inibidores da Protease de HIV/análise , Inibidores da Protease de HIV/síntese química , Concentração de Íons de Hidrogênio , Lopinavir , Espectrometria de Massas , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Preparações Farmacêuticas/análise , Fosfatos/química , Compostos de Potássio/química , Pirimidinonas/análise , Pirimidinonas/síntese química , Controle de Qualidade , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Fatores de Tempo , Água/química
13.
Cell Death Discov ; 4: 43, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30302277

RESUMO

The precise role of autophagy in P. falciparum remains largely unknown. Although a limited number of autophagy genes have been identified in this apicomplexan, only PfAtg8 has been characterized to a certain extent. On the basis of the expression levels of PfAtg8 and the putative PfAtg5, we report that the basal autophagy in this parasite is quite robust and mediates not only the intraerythrocytic development but also fresh invasion of red blood cells (RBCs) in the subsequent cycles. We demonstrate that the basal autophagy responds to both inducers and inhibitors of autophagy. In addition, the parasite survival upon starvation is temporally governed by the autophagy status. Brief periods of starvation, which induces autophagy, help survival while prolonged starvation decreases autophagy leading to stalled parasite growth and reduced invasion. Thus, starvation-induced autophagy is context dependent. Importantly, we report characterization of another autophagy marker in this parasite, the putative PfAtg5 (Pf3D7_1430400). PfAtg5 is expressed in all the intraerythrocytic stages and partially colocalizes with ER, mitochondria, apicoplast and PfAtg8. It is also present on the double membrane bound vesicles. Altogether, these studies pave way for the detailed dissection of P. falciparum autophagy machinery and insights into molecular and functional characterization of its players for developing new therapeutics as antimalarials.

14.
J Chem Neuroanat ; 81: 48-52, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28163215

RESUMO

Cytoplasmic mislocalisation and aggregation of TDP-43 and FUS/TLS proteins in spinal motor neurons contribute to the pathogenesis of the highly fatal disorder amyotrophic lateral sclerosis (ALS). We investigated the neuroprotective effect of VEGF on expression of these proteins in the motor neuronal cell line NSC-34 modelled to reminisce sporadic form of ALS. We studied the expression of TDP-43 and FUS/TLS proteins after exposure to ALS-CSF and following VEGF supplementation by quantitative confocal microscopy and electron microscopy. ALS-CSF caused cytoplasmic overexpression of both the proteins and stress-granule formation in the cells. These alterations were alleviated by VEGF supplementation. The related ultrastructural changes like nuclear membrane dysmorphism and p-bodies associated changes were also reversed. However the protein expression did not completely translocate to the nucleus, as some cells continued to show to cytoplasmic mislocalisation. Thus, the present findings indicate that VEGF alleviates TDP43 and FUS pathology by complimenting its role in controlling apoptosis and reversing choline acetyl transferase expression. Hence, VEGF appears to target multiple pathogenic processes in the neurodegenerative cascade of ALS.


Assuntos
Esclerose Lateral Amiotrófica/líquido cefalorraquidiano , Citoplasma/metabolismo , Proteínas de Ligação a DNA/biossíntese , Proteína FUS de Ligação a RNA/biossíntese , Fator A de Crescimento do Endotélio Vascular/farmacologia , Adulto , Esclerose Lateral Amiotrófica/patologia , Biomarcadores/líquido cefalorraquidiano , Linhagem Celular , Citoplasma/efeitos dos fármacos , Citoplasma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Int J Surg Pathol ; 24(7): 663-7, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27194402

RESUMO

Chordoid glioma (CG) is a World Health Organization classified grade II tumor located exclusively in the region of anterior third ventricle. Association of CG with other lesions is extremely rare. We report a case of CG in a 45-year-old male coexisting with an epidermoid cyst in the third ventricle. Ultrastructural examination of the CG revealed microvilli, junctional complexes, and intermediate filaments within the cytoplasm suggesting origin from specialized ependyma. The association of the 2 lesions appears coincidental as convincing evidence for a common histogenesis was not found.


Assuntos
Encefalopatias/complicações , Neoplasias do Ventrículo Cerebral/complicações , Cisto Epidérmico/complicações , Glioma/complicações , Terceiro Ventrículo/patologia , Biomarcadores Tumorais/análise , Encefalopatias/patologia , Neoplasias do Ventrículo Cerebral/patologia , Neoplasias do Ventrículo Cerebral/ultraestrutura , Cisto Epidérmico/patologia , Cisto Epidérmico/ultraestrutura , Glioma/patologia , Glioma/ultraestrutura , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Terceiro Ventrículo/ultraestrutura
16.
Behav Brain Res ; 259: 60-9, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24183945

RESUMO

Memory impairment during aging is believed to be a consequence of decline in neuronal function and increase in neurodegeneration. Accumulation of oxidative damage and reduction of antioxidant defense system play a key role in organismal aging and functional senescence. In our study, we examined the age-related memory impairment (AMI) in relation to oxidative stress using Drosophila model. We observed a decline in cognitive function in old flies with respect to both short-lived and consolidated forms of olfactory memory. Light and electron microscopy of mushroom bodies revealed a reduction in the number of synapses and discernible architectural defects in mitochondria. An increase in neuronal apoptosis in Kenyon cells was also evident in aged flies. Biochemical investigations revealed a comparable age-associated decrease in the activity of antioxidant enzymes such as catalase and superoxide dismutase as well as the GSH level, accompanied by an increase in the level of lipid peroxidation and generation of reactive oxygen species in the brain. There was no significant difference in the activity level of AChE and BChE enzymes between different age groups while immunohistochemical studies showed a significant decrease in the level of ChAT in 50-day-old flies. RNAi-mediated silencing of cat and sod1 genes caused severe memory impairment in 15-day-old flies, whereas, over-expression of cat gene could partially rescue the memory loss in the old flies. We demonstrated that a Drosophila long-lived strain, possessing enhanced activity of antioxidant enzymes and higher rate of resistance to oxidative stress, shows lower extent of AMI compared to normal lifespan strain. Present study provides evidence for involvement of oxidative stress in AMI in Drosophila.


Assuntos
Envelhecimento , Encéfalo/patologia , Drosophila melanogaster/fisiologia , Transtornos da Memória/patologia , Estresse Oxidativo/fisiologia , Acetilcolina/metabolismo , Envelhecimento/genética , Animais , Animais Geneticamente Modificados , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Catalase/genética , Catalase/metabolismo , Colina/análogos & derivados , Colina/metabolismo , Colina O-Acetiltransferase/metabolismo , Condicionamento Clássico/fisiologia , Proteínas de Drosophila/genética , Regulação da Expressão Gênica/genética , Glutationa/metabolismo , Peroxidação de Lipídeos/genética , Transtornos da Memória/genética , Corpos Pedunculados/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Olfato/fisiologia , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1 , Fatores de Tempo
17.
Indian J Psychiatry ; 55(2): 204-5, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23825863

RESUMO

BACKGROUND: In animal models, stress and depression are associated with excitatory changes in the amygdala; this aberrant neuroplasticity may represent increased fear learning, explaining the anxiety, fear, and related symptoms that characterize clinical depression. MATERIALS AND METHODS: In a pilot investigation, we treated adult, male, Wistar rats with sham electroconvulsive shocks (ECS; n=3), low-dose ECS (10 mC; n=3), and high-dose ECS (60 mC; n=3). The rats were sacrificed 1 month after the last of 6 once-daily ECS and, after dissection, sections of the basolateral amygdala were examined using transmission electron microscopy under low (×11,000) and high (×30,000) magnification. RESULTS: In each group, 4 fields were examined under low magnification and 6 fields under high magnification. The number of excitatory synapses and the ratio of excitatory to inhibitory synapses were both numerically lower with ECS than with sham ECS, and the effect was stronger in the high-dose ECS group (statistical analyses were not performed because this was a pilot study). CONCLUSIONS: By reducing the number of excitatory synapses and the ratio of excitatory to inhibitory synapses, ECT (especially high-dose ECT) may reduce stress-induced excitatory changes in the amygdala. These changes may help explain a part of the benefits observed with ECT in conditions such as depression and post-traumatic stress disorder.

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