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1.
AAPS PharmSciTech ; 20(8): 332, 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31705211

RESUMO

Individualized dosing is often required in pharmacotherapy, particularly for pediatric and geriatric patients and adjustment of drugs that demand dose adaptation. This study aimed to evaluate critical quality attributes (CQAs) of doses obtained by distinct approaches for achieving individual dosing. Approaches were evaluated as follows: subdivision of tablets by splitter and hand (haloperidol) and delivery by plastic dropper bottle (haloperidol), glass dropper bottle (clonazepam), dosing cup (sodium valproate), and dosing syringe (carbamazepine), including brand name, generic, and similar marketed products. Measuring devices were packaged with their respective product. Drug content uniformity was assessed to each substance according to pharmacopeial methods. Tablets subdivided by splitter had the poorest performance among all approaches, in which doses ranged around 60% of the labeled amount (Acceptance Value = 58.1 and RSD = 23.2%). The greatest performances were observed for the dosing syringe which fulfilled all the requirements for dose precision and for the glass dropper bottle. There were significant differences in dose delivery between manufacturers of the same medicine when measuring the same volume or number of drops. High drug content variability is extremely harmful to pharmacotherapy and may result in therapeutic failure or toxicity. It is crucial that measuring devices and scoring of tablets be checked for functionality and standardized for different manufacturers of the same medicine. Part of the approaches for achieving individual dosing did not meet the quality needs for drug content and uniformity. Yet, our findings show that more accurate and precise dosing can be accessed when using the dosing syringe and glass dropper bottle.

2.
Inflamm Res ; 68(10): 845-855, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31218444

RESUMO

INTRODUCTION: Carboxypeptidase M (CPM) is a glycosylphosphatidylinositol anchored enzyme that plays an important role in the kallikrein-kinin system (KKS). CPM catalytic domain hydrolyzes Arg from C-terminal peptides (i.e., bradykinin and kallidin), generating des-Arg-kinins, the agonists of B1 receptor (B1R). It is known that CPM and kinin B1R are co-localized in the plasma membrane microdomains, where they interact with each other, facilitating receptor signaling. AIMS: We hypothesized here that this CPM-B1R interaction could also affect the activity of the enzyme. METHODS: Thus, in this work, we evaluated the impact of B1R presence or absence on CPM activity and expression, using primary culture of microvascular endothelial cells from wild-type, kinin B1R knockout mice (B 1 -/- ), and transgenic rats overexpressing B1 receptor exclusively in the endothelium. In addition, HEK293T cells, as wells as B 1 -/- primary culture of endothelial cells, both transfected with B1R, were also used. RESULTS: CPM expression and activity were downregulated in cells of knockout mice compared to control and this reduction was rescued after B1R transfection. Cells overexpressing B1R presented higher levels of CPM mRNA, protein, and activity. This profile was reverted by pre-incubation with the B1R antagonist, R715, in highly expressing receptor cells. CONCLUSIONS: Our data show that kinin B1R positively modulates both CPM expression and activity, suggesting that CPM-B1R interaction in membrane microdomains might affect enzyme activity, beyond interfering in receptors signaling. This work highlights the interactions among different components of KKS and contributes to a better understanding of its patho-physiological role.

4.
Front Neurol ; 10: 382, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31040818

RESUMO

The maintenance of blood-brain barrier (BBB) integrity is essential for providing a suitable environment for nervous tissue function. BBB disruption is involved in many central nervous system diseases, including epilepsy. Evidence demonstrates that BBB breakdown may induce epileptic seizures, and conversely, seizure-induced BBB disruption may cause further epileptic episodes. This study was conducted based on the premise that the impairment of brain tissue during the triggering event may determine the organization and functioning of the brain during epileptogenesis, and that BBB may have a key role in this process. Our purpose was to investigate in rats the relationship between pilocarpine-induced status epilepticus (SE), and BBB integrity by determining the time course of the BBB opening and its subsequent recovery during the acute phase of the pilocarpine model. BBB integrity was assessed by quantitative and morphological methods, using sodium fluorescein and Evans blue (EB) dyes as markers of the increased permeability to micromolecules and macromolecules, respectively. Different time-points of the pilocarpine model were analyzed: 30 min after pilocarpine injection and then 1, 5, and 24 h after the SE onset. Our results show that BBB breakdown is a dynamic phenomenon and time-dependent, i.e., it happens at specific time-points of the acute phase of pilocarpine model of epilepsy, recovering in part its integrity afterwards. Pilocarpine-induced changes on brain tissue initially increases the BBB permeability to micromolecules, and subsequently, around 5 h after SE, the BBB breakdown to macromolecules occurs. After BBB breakdown, EB dye is captured by damaged cells, especially neurons, astrocytes, and oligodendrocytes. Although the BBB permeability to macromolecules is restored 24 h after the start of SE, the leakage of micromolecules persists and the consequences of BBB degradation are widely disseminated in the brain. Our findings reveal the existence of a temporal window of BBB dysfunction in the acute phase of the pilocarpine model that is important for the development of therapeutic strategies that could prevent the epileptogenesis.

5.
J Bras Pneumol ; 42(3): 211-4, 2016.
Artigo em Inglês, Português | MEDLINE | ID: mdl-27383935

RESUMO

Obstructive sleep apnea (OSA) has been associated with oxidative stress and various cardiovascular consequences, such as increased cardiovascular disease risk. Quantitative real-time PCR is frequently employed to assess changes in gene expression in experimental models. In this study, we analyzed the effects of chronic intermittent hypoxia (an experimental model of OSA) on housekeeping gene expression in the left cardiac ventricle of rats. Analyses via four different approaches-use of the geNorm, BestKeeper, and NormFinder algorithms; and 2-ΔCt (threshold cycle) data analysis-produced similar results: all genes were found to be suitable for use, glyceraldehyde-3-phosphate dehydrogenase and 18S being classified as the most and the least stable, respectively. The use of more than one housekeeping gene is strongly advised. RESUMO A apneia obstrutiva do sono (AOS) tem sido associada ao estresse oxidativo e a várias consequências cardiovasculares, tais como risco aumentado de doença cardiovascular. A PCR quantitativa em tempo real é frequentemente empregada para avaliar alterações na expressão gênica em modelos experimentais. Neste estudo, analisamos os efeitos da hipóxia intermitente crônica (um modelo experimental de AOS) na expressão de genes de referência no ventrículo cardíaco esquerdo de ratos. Análises a partir de quatro abordagens - uso dos algoritmos geNorm, BestKeeper e NormFinder e análise de dados 2-ΔCt (ciclo limiar) - produziram resultados semelhantes: todos os genes mostraram-se adequados para uso, sendo que gliceraldeído-3-fosfato desidrogenase e 18S foram classificados como o mais e o menos estável, respectivamente. A utilização de mais de um gene de referência é altamente recomendada.


Assuntos
Expressão Gênica , Genes Essenciais , Ventrículos do Coração , Hipóxia/genética , Apneia Obstrutiva do Sono/genética , Animais , Modelos Animais de Doenças , Ventrículos do Coração/fisiopatologia , Hipóxia/fisiopatologia , Masculino , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Valores de Referência , Apneia Obstrutiva do Sono/fisiopatologia
6.
J Bras Pneumol ; 41(1): 39-47, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25750673

RESUMO

OBJECTIVE: Obstructive sleep apnea syndrome is mainly characterized by intermittent hypoxia (IH) during sleep, being associated with several complications. Exposure to IH is the most widely used animal model of sleep apnea, short-term IH exposure resulting in cognitive and neuronal impairment. Pigment epithelium-derived factor (PEDF) is a hypoxia-sensitive factor acting as a neurotrophic, neuroprotective, and antiangiogenic agent. Our study analyzed performance on learning and cognitive tasks, as well as PEDF gene expression and PEDF protein expression in specific brain structures, in rats exposed to long-term IH. METHODS: Male Wistar rats were exposed to IH (oxygen concentrations of 21-5%) for 6 weeks-the chronic IH (CIH) group-or normoxia for 6 weeks-the control group. After CIH exposure, a group of rats were allowed to recover under normoxic conditions for 2 weeks (the CIH+N group). All rats underwent the Morris water maze test for learning and memory, PEDF gene expression and PEDF protein expression in the hippocampus, frontal cortex, and temporal cortex being subsequently assessed. RESULTS: The CIH and CIH+N groups showed increased PEDF gene expression in the temporal cortex, PEDF protein expression remaining unaltered. PEDF gene expression and PEDF protein expression remained unaltered in the frontal cortex and hippocampus. Long-term exposure to IH did not affect cognitive function. CONCLUSIONS: Long-term exposure to IH selectively increases PEDF gene expression at the transcriptional level, although only in the temporal cortex. This increase is probably a protective mechanism against IH-induced injury.


Assuntos
Proteínas do Olho/genética , Expressão Gênica , Hipóxia/genética , Fatores de Crescimento Neural/genética , Serpinas/genética , Apneia Obstrutiva do Sono/genética , Animais , Transtornos Cognitivos/etiologia , Modelos Animais de Doenças , Hipocampo/patologia , Hipóxia/fisiopatologia , Masculino , Memória , Transtornos da Memória/etiologia , Ratos , Ratos Wistar , Apneia Obstrutiva do Sono/fisiopatologia
7.
J. bras. pneumol ; 41(1): 39-47, Jan-Feb/2015. tab, graf
Artigo em Inglês | LILACS | ID: lil-741566

RESUMO

Objective: Obstructive sleep apnea syndrome is mainly characterized by intermittent hypoxia (IH) during sleep, being associated with several complications. Exposure to IH is the most widely used animal model of sleep apnea, short-term IH exposure resulting in cognitive and neuronal impairment. Pigment epithelium-derived factor (PEDF) is a hypoxia-sensitive factor acting as a neurotrophic, neuroprotective, and antiangiogenic agent. Our study analyzed performance on learning and cognitive tasks, as well as PEDF gene expression and PEDF protein expression in specific brain structures, in rats exposed to long-term IH. Methods: Male Wistar rats were exposed to IH (oxygen concentrations of 21-5%) for 6 weeks-the chronic IH (CIH) group-or normoxia for 6 weeks-the control group. After CIH exposure, a group of rats were allowed to recover under normoxic conditions for 2 weeks (the CIH+N group). All rats underwent the Morris water maze test for learning and memory, PEDF gene expression and PEDF protein expression in the hippocampus, frontal cortex, and temporal cortex being subsequently assessed. Results: The CIH and CIH+N groups showed increased PEDF gene expression in the temporal cortex, PEDF protein expression remaining unaltered. PEDF gene expression and PEDF protein expression remained unaltered in the frontal cortex and hippocampus. Long-term exposure to IH did not affect cognitive function. Conclusions: Long-term exposure to IH selectively increases PEDF gene expression at the transcriptional level, although only in the temporal cortex. This increase is probably a protective mechanism against IH-induced injury. .


Objetivo: A síndrome da apneia obstrutiva do sono caracteriza-se principalmente por episódios de hipóxia intermitente (HI) durante o sono e associa-se a diversas complicações. A exposição à HI é o mais usado modelo animal de apneia do sono, e protocolos de curta duração causam diversos prejuízos cognitivos e neuronais. Pigment epithelium-derived factor (PEDF, fator derivado do epitélio pigmentado) é um fator neurotrófico, neuroprotetor e antiangiogênico sensível à hipóxia celular. Nosso estudo analisou o desempenho em tarefas cognitivas e de aprendizagem, bem como a expressão do gene PEDF e da proteína PEDF em estruturas cerebrais específicas em ratos expostos a HI de longa duração. Métodos: Ratos Wistar foram expostos a HI (21-5% de oxigênio) durante 6 semanas - o grupo HI crônica (HIC) - ou a normóxia durante 6 semanas - o grupo controle. Após a exposição à HIC, um grupo de ratos foi exposto a normóxia durante 2 semanas (o grupo HIC+N). Todos os animais foram submetidos ao labirinto aquático de Morris para avaliação de memória e aprendizado; avaliou-se também a expressão do gene PEDF e da proteína PEDF no hipocampo e nos córtices frontal e temporal. Resultados: Os grupos HIC e HIC+N apresentaram um aumento de expressão do gene PEDF no córtex temporal, porém sem aumento dos níveis proteicos. A expressão do gene PEDF e da proteína PEDF manteve-se inalterada nas demais estruturas. A exposição de longa duração à HI não afetou a função cognitiva. Conclusões: A exposição de longa duração à HI aumenta seletivamente a expressão do gene PEDF ao nível transcricional, embora apenas no córtex temporal. Esse aumento é provavelmente um mecanismo de proteção contra a HI. .


Assuntos
Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Glicemia/metabolismo , Doenças Cardiovasculares/prevenção & controle , Dieta com Restrição de Carboidratos , Dieta com Restrição de Gorduras , /prevenção & controle , Programas de Redução de Peso , Perda de Peso/fisiologia , Peso Corporal , Estudos de Casos e Controles , Ensaio Clínico , Seguimentos , Hemoglobina A Glicada/análise , Obesidade/dietoterapia , Obesidade/metabolismo , Obesidade/fisiopatologia , Sobrepeso/dietoterapia , Sobrepeso/metabolismo , Sobrepeso/fisiopatologia , Fatores de Risco
8.
Obesity (Silver Spring) ; 23(2): 391-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25557274

RESUMO

OBJECTIVE: Epidemiological studies show the association of sleep restriction (SR) with obesity and insulin resistance. Experimental studies are limited to the concurrent or short-term effects of SR. Here, we examined the late effects of SR regarding weight gain and metabolic alterations induced by a high-fat diet (HFD). METHODS: C57BL/6 mice were subjected to a multiple platform method of SR for 15 days, 21 h daily, followed by 6 weeks of a 30% HFD. RESULTS: Just after SR, serum insulin and resistin concentrations were increased and glycerol content decreased. In addition, resistin, TNF-α, and IL-6 mRNA expression were notably increased in epididymal fat. At the end of the HFD period, mice previously submitted to SR gained more weight (32.3 ± 1.0 vs. 29.4 ± 0.7 g) with increased subcutaneous fat mass, had increments in the expression of the adipogenic genes PPARγ, C/EBPα, and C/EBPß, and had macrophage infiltration in the epididymal adipose tissue. Furthermore, enhanced glucose tolerance and insulin resistance were also observed. CONCLUSIONS: The consequences of SR may last for a long period, characterizing SR as a predisposing factor for weight gain and insulin resistance. Metabolic changes during SR seem to prime adipose tissue, aggravating the harmful effects of diet-induced obesity.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Resistência à Insulina/fisiologia , Obesidade/etiologia , Privação do Sono/complicações , Ganho de Peso , Tecido Adiposo/metabolismo , Animais , Peso Corporal , Modelos Animais de Doenças , Seguimentos , Insulina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/metabolismo , Obesidade/fisiopatologia , Privação do Sono/metabolismo , Privação do Sono/fisiopatologia , Fatores de Tempo
9.
PLoS One ; 9(10): e109902, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25289636

RESUMO

Obstructive sleep apnea (OSA) is a syndrome characterized by intermittent nocturnal hypoxia, sleep fragmentation, hypercapnia and respiratory effort, and it has been associated with several complications, such as diabetes, hypertension and obesity. Quantitative real-time PCR has been performed in previous OSA-related studies; however, these studies were not validated using proper reference genes. We have examined the effects of chronic intermittent hypoxia (CIH), which is an experimental model mainly of cardiovascular consequences of OSA, on reference genes, including beta-actin, beta-2-microglobulin, glyceraldehyde-3-phosphate dehydrogenase, hypoxanthine guanine phosphoribosyl transferase and eukaryotic 18S rRNA, in different areas of the brain. All stability analyses were performed using the geNorm, Normfinder and BestKeeper software programs. With exception of the 18S rRNA, all of the evaluated genes were shown to be stable following CIH exposure. However, gene stability rankings were dependent on the area of the brain that was analyzed and varied according to the software that was used. This study demonstrated that CIH affects various brain structures differently. With the exception of the 18S rRNA, all of the tested genes are suitable for use as housekeeping genes in expression analyses.


Assuntos
Encéfalo/metabolismo , Genes Essenciais , Hipóxia/genética , Reação em Cadeia da Polimerase em Tempo Real/normas , Apneia Obstrutiva do Sono/genética , Software , Actinas/genética , Actinas/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Mapeamento Encefálico , Modelos Animais de Doenças , Expressão Gênica , Perfilação da Expressão Gênica , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Humanos , Hipoxantina Fosforribosiltransferase/genética , Hipoxantina Fosforribosiltransferase/metabolismo , Hipóxia/metabolismo , Hipóxia/patologia , Masculino , Oxigênio/farmacologia , RNA Ribossômico 18S/genética , RNA Ribossômico 18S/metabolismo , Ratos , Ratos Wistar , Padrões de Referência , Apneia Obstrutiva do Sono/metabolismo , Apneia Obstrutiva do Sono/patologia , Microglobulina beta-2/genética , Microglobulina beta-2/metabolismo
10.
Epilepsia ; 55(5): 754-62, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24702695

RESUMO

OBJECTIVE: Thimet oligopeptidase (TOP) is a metalloprotease that has been associated with peptide processing in several nervous system structures, and its substrates include several peptides such as bradykinin, amyloid beta (Aß), and major histocompatibility complex (MHC) class I molecules. As shown previously by our research group, patients with temporal lobe epilepsy (TLE) have a high level of kinin receptors as well as kallikrein, a kinin-releasing enzyme, in the hippocampus. METHODS: In this study, we evaluated the expression, distribution, and activity of TOP in the hippocampus of patients with TLE and autopsy-control tissues, through reverse-transcription polymerase chain reaction (RT-PCR), enzymatic activity, Western blot, and immunohistochemistry. In addition, hippocampi of rats were analyzed using the pilocarpine-induced epilepsy model. Animals were grouped according to the epilepsy phases defined in the model as acute, silent, and chronic. RESULTS: Increased TOP mRNA expression, decreased protein levels and enzymatic activity were observed in tissues of patients, compared to control samples. In addition, decreased TOP distribution was also visualized by immunohistochemistry. Similar results were observed in tissues of rats during the acute phase of epilepsy model. However, increased TOP mRNA expression and no changes in immunoreactivity were found in the silent phase, whereas increased TOP mRNA expression and increased enzymatic activity were observed in the chronic phase. SIGNIFICANCE: The results show that these alterations could be related to a failure in the mechanisms involved in clearance of inflammatory peptides in the hippocampus, suggesting an accumulation of potentially harmful substances in nervous tissue such as Aß, bradykinin, and antigenic peptides. These accumulations could be related to hippocampal inflammation observed in TLE subjects.


Assuntos
Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/patologia , Hipocampo/patologia , Metaloendopeptidases/genética , RNA Mensageiro/genética , Adulto , Animais , Lobectomia Temporal Anterior , Modelos Animais de Doenças , Epilepsia do Lobo Temporal/cirurgia , Feminino , Regulação Enzimológica da Expressão Gênica/genética , Hipocampo/cirurgia , Humanos , Injeções Intraperitoneais , Masculino , Pessoa de Meia-Idade , Pilocarpina , Ratos , Esclerose , Lobo Temporal/patologia , Adulto Jovem
11.
Rev. bras. ecocardiogr ; 19(1): 59-64, jan.-mar. 2006. ilus
Artigo em Português | LILACS | ID: lil-427574

RESUMO

A síndrome de Ehlers-Danlos é um distúrbio hereditário raro do tecido conjuntivo resultando em grande flexibilidade das articulações, hérnia inguinal, aumento da elasticidade da pele e lesões do sistema cardiovascular, envolvendo o coração e artérias sistêmicas e pulmonares. Neste artigo relata-se o caso de um menino com diagnóstico prévio da síndrome que em avaliação pré-operatória de hérnia inguinal tinha sintomas de dispnéia e sopro, ao ecocardiograma Doppler foram observados sinais de estenoses do ramo esquerdo da artéria pulmonar. A angiografia pulmonar confirmou anomalias significativas e foi realizada angioplastia, entretanto, o paciente voltou a ter sintomas sendo então realizado tratamento cirúrgico. O paciente evoluiu com melhora clínica significativa e modificação do padrão de fluxo das artérias pulmonares avaliado pela ecocardiografia Doppler.


Assuntos
Criança , Masculino , Humanos , Artéria Pulmonar/anormalidades , Ecocardiografia Doppler/métodos , Síndrome de Ehlers-Danlos/complicações , Síndrome de Ehlers-Danlos/diagnóstico , Estenose da Valva Pulmonar/complicações , Estenose da Valva Pulmonar/diagnóstico
12.
Eur J Biochem ; 269(11): 2747-54, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12047384

RESUMO

Human glandular kallikrein 2 (hK2) is a trypsin-like serine protease expressed predominantly in the prostate epithelium. Recently, hK2 has proven to be a useful marker that can be used in combination with prostate specific antigen for screening and diagnosis of prostate cancer. The cleavage by hK2 of certain substrates in the proteolytic cascade suggest that the kallikrein may be involved in prostate cancer development; however, there has been very little other progress toward its biochemical characterization or elucidation of its true physiological role. In the present work, we adapt phage substrate technology to study the substrate specificity of hK2. A phage-displayed random pentapeptide library with exhaustive diversity was generated and then screened with purified hK2. Phages displaying peptides susceptible to hK2 cleavage were amplified in eight rounds of selection and genes encoding substrates were transferred from the phage to a fluorescent system using cyan fluorescent protein (derived from green fluorescent protein) that enables rapid determination of specificity constants. This study shows that hK2 has a strict preference for Arg in the P1 position, which is further enhanced by a Ser in P'1 position. The scissile bonds identified by phage display substrate selection correspond to those of the natural biological substrates of hK2, which include protein C inhibitor, semenogelins, and fibronectin. Moreover, three new putative hK2 protein substrates, shown elsewhere to be involved in the biology of the cancer, have been identified thus reinforcing the importance of hK2 in prostate cancer development.


Assuntos
Calicreínas Teciduais/metabolismo , Proteínas de Fluorescência Verde , Humanos , Cinética , Proteínas Luminescentes , Biblioteca de Peptídeos , Especificidade por Substrato/genética , Calicreínas Teciduais/genética
13.
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