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1.
Planta Med ; 90(1): 63-72, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37852270

RESUMO

The development of virus-free, oral vaccines against poliovirus capable of inducing mucosal protective immunity is needed to safely combat this pathogen. In the present study, a carrot cell line expressing the poliovirus VP2 antigen was established at the level of callus and cell suspensions, exploring the effects of culture media (MS and B5), supplementation with urea, phytoregulators (2,4-D : KIN), and light conditions (continuous light, photoperiod, and total darkness). The best callus growth was obtained on B5 medium supplemented with 2 mg/L of 2,4-D + 2 mg/L kinetin and 0.0136 g/L of urea and in continuous light conditions. Suspension cultures of the SMC-1 line in 250 mL Erlenmeyer flasks had a maximum growth of 16.07 ± 0.03 g/L DW on day 12 with a growth rate of µ=0.3/d and a doubling time of 2.3 days. In a 2 L airlift bioreactor, the biomass yield achieved was 25.6 ± 0.05 g/L DW at day 10 with a growth rate of µ= 0.58/d and doubling time of 1.38 d. Cell growth was 1.5 times higher in bioreactors than in shake flasks, highlighting that both systems resulted in the accumulation of VP2 throughout the time in culture. The maximum VP2 yield in flasks was 387.8 µg/g DW at day 21, while in the reactor it was 550.2 µg/g DW at day 18. In conclusion, bioreactor-based production of the VP2 protein by the SMC-1 suspension cell line offers a higher productivity when compared to flask cultures, offering a key perspective to produce low-cost vaccines against poliomyelitis.


Assuntos
Daucus carota , Vacinas contra Poliovirus , Poliovirus , Linhagem Celular , Ureia , Ácido 2,4-Diclorofenoxiacético
2.
Biotechnol Prog ; 39(6): e3390, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37702113

RESUMO

The aggregation and spread of alpha-synuclein (αSyn) is associated with several pathogenic pathways that lead to neurodegeneration and, ultimately, to synucleinopathies development. Hence, the establishment of a safe and effective disease-modifying therapy that limits or prevents the spread of toxic αSyn aggregation could lead to positive clinical outcomes. A rational vaccine design can be focused on the selection of specific epitopes able to induce the immune response desired, for example, antibodies able to mediate the clearance of αSyn aggregates without the induction of inflammatory responses. To develop a rapid system for the evaluation of a vaccine candidate against synucleinopathies, rLTB-Syn (an antigen based on three B cell epitopes from αSyn and the B subunit of the heat-labile Escherichia coli enterotoxin [LTB] as adjuvant/carrier) was produced using recombinant E. coli (Rosetta DE3) as the expression host. The bacterial version of rLTB-Syn was produced as soluble protein at yields up to 1.72 mg/g biomass. A method for the purification of rLTB-Syn (~18 kDa) was developed based on ion exchange chromatography, reaching purity >93% with a final concentration of 82.6 µg/mL. Furthermore, the purified soluble rLTB-Syn retained GM1 binding activity, suggesting proper folding and pentameric structure. The results from this study establish a fast and effective method to obtain rLTB-Syn, making it useful in the design of novel vaccine formulations targeting synucleinopathies.


Assuntos
Toxinas Bacterianas , Proteínas de Escherichia coli , Sinucleinopatias , Vacinas , Humanos , Escherichia coli/genética , Escherichia coli/metabolismo , Epitopos , Proteínas Recombinantes/metabolismo , Imunoterapia , Proteínas Recombinantes de Fusão/genética
3.
Am J Trop Med Hyg ; 109(3): 523-526, 2023 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-37524331

RESUMO

Peru was severely affected by COVID-19 with a fatality rate that reached up to 6%. In this study, the relationship between SARS-CoV-2 variants and COVID-19 disease outcome in Amazonas, a region of northeastern Peru, was evaluated. The variants were determined by genomic sequencing, and clinical-epidemiological data were collected from 590 patients between April 2021 and February 2022. There was no association between mortality and hospitalization with any of the variants, but we did find that Omicron is more likely to infect vaccinated and nonvaccinated people. A significant association was also found between unvaccinated patients and hospitalization. Interestingly, in the indigenous population, there were fewer hospitalizations than in the general population. In conclusion, SARS-CoV-2 variants were not associated with the disease outcome in the Amazonas region, and indigenous population were found to be less vulnerable to severe COVID-19 illness.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Prevalência , Peru/epidemiologia
4.
Rev. Fac. Med. Hum ; 23(3)jul. 2023.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1535193

RESUMO

Introducción: El aumento de casos de dengue en Amazonas es un riesgo para la salud pública. En el 2021, Balsas reportó por primera vez un brote de dengue. Métodos: La población incluyó a pacientes que cumplían con la definición de caso entre diciembre 2021 y febrero 2022. La identificación de los serotipos se determinó mediante una qRT-PCR múltiplex. Resultados: Se identificaron 72 pacientes de los cuales 53 (74%) se confirmaron por serología (Ag NS1). El serotipo prevalente fue DENV-2 (94%), y el 6% fue DENV-1. Los pacientes de 19 a 45 años presentaron el mayor porcentaje de casos (59%). Los síntomas más frecuentes fueron cefalea, mialgias, fiebre y artralgias; el 23 % presentó dolor abdominal intenso. Conclusión: Este fue el primer brote de dengue confirmado en el distrito de Balsas, siendo DENV-2 el principal causante, destacando la necesidad de mejorar la vigilancia en zonas sin transmisión autóctona de la enfermedad.


Introduction: The increase in dengue cases in Amazonas represents a public health risk. In 2021, Balsas reported a dengue outbreak for the first time. Methods: The population included patients who met the case definition between December 2021 and February 2022. Serotype identification was determined using a multiplex qRT-PCR. Results: A total of 72 patients were identified, of which 53 (74%) were confirmed by serology (NS1 Ag). The prevalent serotype was DENV-2 (94%), and 6% were DENV-1. Patients aged 19 to 45 years had the highest percentage of cases (59%). The most frequent symptoms were headache, myalgia, fever, and arthralgia; 23% had intense abdominal pain. Conclusion: This was the first confirmed dengue outbreak in the Balsas district, with DENV-2 being the main cause of the outbreak, highlighting the need to improve surveillance in areas without autochthonous transmission of the disease.

5.
Rev. Fac. Med. Hum ; 22(3): 533-539, julio-Septiembre 2022.
Artigo em Inglês, Espanhol | LILACS-Express | LILACS | ID: biblio-1381859

RESUMO

Introducción En los últimos años, el número de casos de malaria en las comunidades nativas de Condorcanqui, Amazonas ha aumentado considerablemente. La malaria por Plasmodium vivax es endémica en la región y en 2019 fue reportada la reintroducción de P. falciparum. Métodos En este estudio, recopilamos y analizamos los datos de malaria y COVID-19 reportados por la Dirección Regional de Salud (DIRESA) durante el 2020. Además, realizamos un análisis de razón de posibilidades "odds ratio" para evaluar las asociaciones significativas entre los síntomas de la COVID-19 y las infecciones previas de malaria. Resultados En el 2020, se reportaron 1547 casos de malaria (97% por P. vivax) y 5968 de COVID-19. Por otro lado, 96 pacientes contrajeron COVID-19 después de contraer una infección de malaria. De éstos, 87 eran sintomáticos (90,6%) y en su mayoría adultos de 30 a 59 años (62,3%). Además, encontramos que las infecciones previas de malaria están asociadas a la presencia de síntomas como fiebre, tos, dolor de garganta y dificultad respiratoria. Sin embargo, no hubo asociación significativa entre estos casos y la hospitalización o la muerte. Conclusión Nuestro análisis sugiere que las infecciones previas por malaria podrían afectar la sintomatología de la COVID-19, lo que destaca la importancia de un programa continuo de control y vigilancia de la malaria para evitar posibles sindemias con la COVID-19.


Introduction In recent years, the number of malaria cases in native communities from Condorcanqui, Amazonas has considerably increased. Plasmodium vivax malaria is endemic in the region and the re-introduction of P. falciparum was reported in 2019. Methods Here, we compiled and analyzed malaria and COVID-19 data reported by the Regional Direction of Health (DIRESA) during the 2020. Additionally, we performed an odds ratio analysis to evaluate significant associations between COVID-19 symptoms and previous malaria infections. Results In 2020, 1547 malaria (97% were P. vivax) and 5968 COVID-19 cases were reported. Furthermore, 96 patients got COVID-19 after getting a malaria infection. From these, 87 were symptomatic (90.6%), and mostly adults, ages 30 to 59 (62.3%). Also, we found that malaria previous infections represent a risk for the presence of symptoms such as fever, cough, throat pain, and respiratory difficulty. Nevertheless, there was no significant association between these cases and hospitalization or death. Conclusion Our analysis suggests that previous malaria infections might affect COVID-19 symptomatology, which highlights the importance of a continuing control and surveillance malaria program to avoid potential syndemics with COVID-19.

8.
New Microbiol ; 43(1): 34-37, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32334489

RESUMO

Antimicrobial resistance is a global public health threat. Therefore, surveillance studies are important tools to help direct antimicrobial use. The aim of this study was to investigate antimicrobial resistance in Serratia marcescens isolates collected in 2016-2017 at eight medical centers from two regions of Mexico. Selected S. marcescens isolates were further tested by polymerase chain reaction to detect the presence of genes encoding the ß-lactamases, SHV, TEM or CTX. Antimicrobial resistance continues to be high in Mexico, particularly to ciprofloxacin and aminoglycosides. Also, a widespread prevalence of blaTEM was detected in S. marcescens isolates.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Serratia marcescens , Antibacterianos/farmacologia , México , Testes de Sensibilidade Microbiana , Serratia marcescens/efeitos dos fármacos
9.
J Pak Med Assoc ; 69(7): 1000-1005, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31308571

RESUMO

OBJECTIVE: To estimate the test-retest reliability of measurements in shoulder internal and external rotators' isometric peak torque using a new dynamometer, and to compare it with isokinetic dynamometer. METHODS: The validity study was conducted in September-October 2016 at Pontificia Universidad Catolica de Chile and the Clinica Las Condes, Santiago, Chile. It comprised of asymptomatic university students who were randomly tested twice within a two-week period while in a supine position at 90° of shoulder abduction, using the novel functional electromechanical pulley dynamometer. Concurrent validity was assessed through comparing the values with the gold standard isokinetic dynamometer in the same position. SPSS 17 was used for data analysis. RESULTS: Of the 24 subjects, 5(21%) were males and 19(79%) were females. The overall mean age was 23.1±2.2 years, body mass index 23.6±2.13 kg/m2 and Shoulder Pain and Disability Index score was 3.9±6.4. There was no statistically non-significant difference in terms of test-retest trials and between the devices (p>0.05). Absolute reliability was 24.3% for internal rotation and 27.9% for external rotation. Both dynamometer systems were very highly correlated for internal rotators peak torque (0.93) and highly correlated for external rotators peak torque (0.84). CONCLUSIONS: Compared to the gold standard, the new device was found to be a valid instrument in measuring maximal voluntary isometric peak torque in internal and external rotation.


Assuntos
Contração Isométrica/fisiologia , Dinamômetro de Força Muscular , Força Muscular/fisiologia , Ombro/fisiologia , Torque , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Rotação , Adulto Jovem
10.
J Fungi (Basel) ; 4(3)2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30036959

RESUMO

Sporotrichosis is a subcutaneous mycosis caused by Sporothrix schenckii complex. The disease has been reported worldwide. However, the incidence of the etiological agent varies in its geographic distribution. We studied 39 clinical isolates of Sporothrix schenckii from diverse regions in Mexico, collected from 1998 to 2016. Molecular identification was performed by sequence analysis of the partial calmodulin gene. In vitro antifungal susceptibility to amphotericin B (AMB), itraconazole (ITC), voriconazole (VRC), posaconazole (PSC), fluconazole (FLC), terbinafine (TRB), caspofungin (CSF), anidulafungin (ANF), and micafungin (MCF) was evaluated. Thirty-eight isolates of S. schenckii complex were divided into five supported clades in a phylogenetic tree. The predominant clinical form was lymphocutaneous (92.3%), fixed cutaneous (5.1%), and disseminated (2.5%). Terbinafine exhibited the best in vitro antifungal activity, while fluconazole was ineffective against Sporothrix schenckii complex. Our results showed diverse geographic distribution of clinical isolates in eight states; definitive identification was done by CAL gen PCR-sequencing. In Mexico, S. schenckii is considered to be an etiological agent of human sporotrichosis cases, and lymphocutaneous is the most prevalent form of the disease. This study revealed four clades of S. schenckiisensu stricto by phylogenetic analysis. Furthermore, we report one case of S. globosa isolated from human origin from the North of Mexico.

11.
Prostate ; 78(9): 639-645, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29569731

RESUMO

Prostate cancer (PCa) is a disease of increasing medical significance worldwide. In developed countries, PCa is the most common non-skin cancer in men, and one of the leading causes of cancer-related deaths. Exercise is one of the environmental factors that have been shown to influence cancer risk. Moreover, systemic reviews and meta-analysis have suggested that total physical activity is related to a decrease in the risk of developing PCa. In addition, epidemiological studies have shown that exercise, after diagnosis, has benefits regarding PCa development, and positive outcome in patients under treatment. The standard treatment for locally advanced or metastatic PCa is Androgen deprivation therapy (ADT). ADT produces diverse side effects, including loss of libido, changes in body composition (increase abdominal fat), and reduced muscle mass, and muscle tone. Analysis of numerous research publications showed that aerobic and/or resistance training improve patient's physical condition, such us, cardiorespiratory fitness, muscle strength, physical function, body composition, and fatigue. Therefore, exercise might counteract several ADT treatment-induced side effects. In addition of the aforementioned benefits, epidemiological, and in vitro studies have shown that exercise might decrease PCa development. Thus, physical activity might attenuate the risk of PCa and supervised exercise intervention might improve deleterious effects of cancer treatment, such as ADT side effects. This review article provides evidence indicating that exercise could complement, and potentiate, the current standard treatments for advanced PCa, probably by creating an unfavorable microenvironment that can negatively affect tumor development, and progression.


Assuntos
Exercício Físico/fisiologia , Neoplasias da Próstata/fisiopatologia , Antagonistas de Androgênios/uso terapêutico , Promoção da Saúde , Humanos , Masculino , Prognóstico , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/terapia
12.
Sci Rep ; 6: 33606, 2016 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-27677351

RESUMO

Hypothalamic glucosensing, which involves the detection of glucose concentration changes by brain cells and subsequent release of orexigenic or anorexigenic neuropeptides, is a crucial process that regulates feeding behavior. Arcuate nucleus (AN) neurons are classically thought to be responsible for hypothalamic glucosensing through a direct sensing mechanism; however, recent data has shown a metabolic interaction between tanycytes and AN neurons through lactate that may also be contributing to this process. Monocarboxylate transporter 1 (MCT1) is the main isoform expressed by tanycytes, which could facilitate lactate release to hypothalamic AN neurons. We hypothesize that MCT1 inhibition could alter the metabolic coupling between tanycytes and AN neurons, altering feeding behavior. To test this, we inhibited MCT1 expression using adenovirus-mediated transfection of a shRNA into the third ventricle, transducing ependymal wall cells and tanycytes. Neuropeptide expression and feeding behavior were measured in MCT1-inhibited animals after intracerebroventricular glucose administration following a fasting period. Results showed a loss in glucose regulation of orexigenic neuropeptides and an abnormal expression of anorexigenic neuropeptides in response to fasting. This was accompanied by an increase in food intake and in body weight gain. Taken together, these results indicate that MCT1 expression in tanycytes plays a role in feeding behavior regulation.

13.
J Cell Mol Med ; 19(7): 1471-82, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26081217

RESUMO

Tanycytes are elongated hypothalamic glial cells that cover the basal walls of the third ventricle; their apical regions contact the cerebrospinal fluid (CSF), and their processes reach hypothalamic neuronal nuclei that control the energy status of an organism. These nuclei maintain the balance between energy expenditure and intake, integrating several peripheral signals and triggering cellular responses that modify the feeding behaviour and peripheral glucose homeostasis. One of the most important and well-studied signals that control this process is glucose; however, the mechanism by which this molecule is sensed remains unknown. We along with others have proposed that tanycytes play a key role in this process, transducing changes in CSF glucose concentration to the neurons that control energy status. Recent studies have demonstrated the expression and function of monocarboxylate transporters and canonical pancreatic ß cell glucose sensing molecules, including glucose transporter 2 and glucokinase, in tanycytes. These and other data, which will be discussed in this review, suggest that hypothalamic glucosensing is mediated through a metabolic interaction between tanycytes and neurons through lactate. This article will summarize the recent evidence that supports the importance of tanycytes in hypothalamic glucosensing, and discuss the possible mechanisms involved in this process. Finally, it is important to highlight that a detailed analysis of this mechanism could represent an opportunity to understand the evolution of associated pathologies, including diabetes and obesity, and identify new candidates for therapeutic intervention.


Assuntos
Células Ependimogliais/metabolismo , Glucose/metabolismo , Hipotálamo/citologia , Animais , Comunicação Celular , Glucoquinase/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Humanos
14.
Arq. bras. oftalmol ; Arq. bras. oftalmol;77(6): 395-396, Nov-Dec/2014. graf
Artigo em Inglês | LILACS | ID: lil-735811

RESUMO

Pupil abnormalities in leprosy usually result from chronic iritis with loss of stroma, iris miosis, a sluggish reaction to light, and poor dilation in response to anticholinergic mydriatics. We report two patients with long-standing lepromatous leprosy who developed tonic pupils characterized by mydriasis, absence of reaction to light and hypersensitivity to weak cholinergic solution. Examination revealed iritis and iris atrophy. In both cases, instillation of dilute 0.1% pilocarpine caused miosis in the affected eyes. Tonic pupil occurs in many conditions, but its association with leprosy had not been previously reported.


Anormalidades da pupila em pacientes com doença de Hansen, ocorrem mais comumente devido a irite crônica com perda do estroma iriano, miose, diminuição da reação à luz, e dificuldade de dilatação em resposta a colírios anticolinérgicos. Relatamos dois pacientes com doença de Hansen na forma lepromatosa que desenvolveram pupilas tônicas, caracterizadas por midríase, ausência de reação a luz e para perto e hipersensibilidade a fraca concentração de solução colinérgica. O exame revelou irite e atrofia iriana. Em ambos os casos a instilação de pilocarpina 0,1% causou miose nos olhos afetados. A pupila tônica tem sido relatada em muitas condições, mas sua associação com doença de Hansen ainda não havia sido descrita.


Assuntos
Humanos , Feminino , Adulto , Hanseníase Virchowiana/complicações , Pupila Tônica/etiologia , Pupila Tônica/tratamento farmacológico , Pilocarpina/uso terapêutico , Miose/induzido quimicamente , Resultado do Tratamento , Mióticos/uso terapêutico
15.
Arq Bras Oftalmol ; 77(6): 395-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25627189

RESUMO

Pupil abnormalities in leprosy usually result from chronic iritis with loss of stroma, iris miosis, a sluggish reaction to light, and poor dilation in response to anticholinergic mydriatics. We report two patients with long-standing lepromatous leprosy who developed tonic pupils characterized by mydriasis, absence of reaction to light and hypersensitivity to weak cholinergic solution. Examination revealed iritis and iris atrophy. In both cases, instillation of dilute 0.1% pilocarpine caused miosis in the affected eyes. Tonic pupil occurs in many conditions, but its association with leprosy had not been previously reported.


Assuntos
Hanseníase Virchowiana/complicações , Pupila Tônica/tratamento farmacológico , Pupila Tônica/etiologia , Adulto , Feminino , Humanos , Miose/induzido quimicamente , Mióticos/uso terapêutico , Pilocarpina/uso terapêutico , Resultado do Tratamento
16.
PLoS One ; 8(4): e62532, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23638108

RESUMO

Hypothalamic neurons of the arcuate nucleus control food intake, releasing orexigenic and anorexigenic neuropeptides in response to changes in glucose concentration. Several studies have suggested that the glucosensing mechanism is governed by a metabolic interaction between neurons and glial cells via lactate flux through monocarboxylate transporters (MCTs). Hypothalamic glial cells (tanycytes) release lactate through MCT1 and MCT4; however, similar analyses in neuroendocrine neurons have yet to be undertaken. Using primary rat hypothalamic cell cultures and fluorimetric assays, lactate incorporation was detected. Furthermore, the expression and function of MCT2 was demonstrated in the hypothalamic neuronal cell line, GT1-7, using kinetic and inhibition assays. Moreover, MCT2 expression and localization in the Sprague Dawley rat hypothalamus was analyzed using RT-PCR, in situ hybridization and Western blot analyses. Confocal immunohistochemistry analyses revealed MCT2 localization in neuronal but not glial cells. Moreover, MCT2 was localized to ∼90% of orexigenic and ~60% of anorexigenic neurons as determined by immunolocalization analysis of AgRP and POMC with MCT2-positives neurons. Thus, MCT2 distribution coupled with lactate uptake by hypothalamic neurons suggests that hypothalamic neurons control food intake using lactate to reflect changes in glucose levels.


Assuntos
Anorexia/metabolismo , Núcleo Arqueado do Hipotálamo/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Proteína Relacionada com Agouti/metabolismo , Animais , Anorexia/patologia , Linhagem Celular Tumoral , Células Cultivadas , Ácido Láctico , Masculino , Camundongos , Orexinas , Pró-Opiomelanocortina/metabolismo , Transporte Proteico , Ratos , Ratos Sprague-Dawley
17.
PLoS One ; 7(2): e32409, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22389700

RESUMO

Although previous studies showed that glucose is used to support the metabolic activity of the cartilaginous fish brain, the distribution and expression levels of glucose transporter (GLUT) isoforms remained undetermined. Optic/ultrastructural immunohistochemistry approaches were used to determine the expression of GLUT1 in the glial blood-brain barrier (gBBB). GLUT1 was observed solely in glial cells; it was primarily located in end-feet processes of the gBBB. Western blot analysis showed a protein with a molecular mass of 50 kDa, and partial sequencing confirmed GLUT1 identity. Similar approaches were used to demonstrate increased GLUT1 polarization to both apical and basolateral membranes in choroid plexus epithelial cells. To explore monocarboxylate transporter (MCT) involvement in shark brain metabolism, the expression of MCTs was analyzed. MCT1, 2 and 4 were expressed in endothelial cells; however, only MCT1 and MCT4 were present in glial cells. In neurons, MCT2 was localized at the cell membrane whereas MCT1 was detected within mitochondria. Previous studies demonstrated that hypoxia modified GLUT and MCT expression in mammalian brain cells, which was mediated by the transcription factor, hypoxia inducible factor-1. Similarly, we observed that hypoxia modified MCT1 cellular distribution and MCT4 expression in shark telencephalic area and brain stem, confirming the role of these transporters in hypoxia adaptation. Finally, using three-dimensional ultrastructural microscopy, the interaction between glial end-feet and leaky blood vessels of shark brain was assessed in the present study. These data suggested that the brains of shark may take up glucose from blood using a different mechanism than that used by mammalian brains, which may induce astrocyte-neuron lactate shuttling and metabolic coupling as observed in mammalian brain. Our data suggested that the structural conditions and expression patterns of GLUT1, MCT1, MCT2 and MCT4 in shark brain may establish the molecular foundation of metabolic coupling between glia and neurons.


Assuntos
Barreira Hematoencefálica/citologia , Transportador de Glucose Tipo 1/metabolismo , Transportadores de Ácidos Monocarboxílicos/metabolismo , Animais , Transportador de Glucose Tipo 1/genética , Transportadores de Ácidos Monocarboxílicos/genética , Neuroglia/metabolismo , Tubarões , Simportadores/genética , Simportadores/metabolismo
18.
Glia ; 60(1): 53-68, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21987367

RESUMO

The ventromedial hypothalamus is involved in regulating feeding and satiety behavior, and its neurons interact with specialized ependymal-glial cells, termed tanycytes. The latter express glucose-sensing proteins, including glucose transporter 2, glucokinase, and ATP-sensitive K(+) (K(ATP) ) channels, suggesting their involvement in hypothalamic glucosensing. Here, the transduction mechanism involved in the glucose-induced rise of intracellular free Ca(2+) concentration ([Ca(2+) ](i) ) in cultured ß-tanycytes was examined. Fura-2AM time-lapse fluorescence images revealed that glucose increases the intracellular Ca(2+) signal in a concentration-dependent manner. Glucose transportation, primarily via glucose transporters, and metabolism via anaerobic glycolysis increased connexin 43 (Cx43) hemichannel activity, evaluated by ethidium uptake and whole cell patch clamp recordings, through a K(ATP) channel-dependent pathway. Consequently, ATP export to the extracellular milieu was enhanced, resulting in activation of purinergic P2Y(1) receptors followed by inositol trisphosphate receptor activation and Ca(2+) release from intracellular stores. The present study identifies the mechanism by which glucose increases [Ca(2+) ](i) in tanycytes. It also establishes that Cx43 hemichannels can be rapidly activated under physiological conditions by the sequential activation of glucosensing proteins in normal tanycytes.


Assuntos
Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Conexina 43/metabolismo , Glucose/farmacologia , Líquido Intracelular/metabolismo , Neuroglia/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Sinalização do Cálcio/efeitos dos fármacos , Sinalização do Cálcio/fisiologia , Cátions/metabolismo , Células Cultivadas , Conexina 43/antagonistas & inibidores , Citocalasina B/farmacologia , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Glucoquinase/metabolismo , Glucose/metabolismo , Proteínas de Transporte de Glutamato da Membrana Plasmática/metabolismo , Hipotálamo/citologia , Antígeno Ki-67/metabolismo , Masculino , Potenciais da Membrana/efeitos dos fármacos , Potenciais da Membrana/fisiologia , Microscopia Confocal , Proteínas do Tecido Nervoso/metabolismo , Neuroglia/citologia , Técnicas de Patch-Clamp , Probenecid/farmacologia , Ratos , Ratos Sprague-Dawley , Fator de von Willebrand/metabolismo
19.
Int. j. morphol ; 29(3): 830-834, Sept. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-608666

RESUMO

Obesity is a prevalent disease in Chile. The multitude of cause factors makes it a complex disease and therefore very difficult to treat, since its roots lie in the earliest stages of life. We evaluated pupils from 21 municipalized primary schools, in rural and urban communities from the 10 districts of the IX region. The sample consisted of 275 subjects in Kindergarten and first year primary school in the year 2008, who were monitored over two years. The results show a trend indicating an increase in the prevalence of obesity in the sample, the difference being statistically significant, p=0.000. These results show that obesity is increasing, and that more action is needed to slow this disease occurring from early childhood.


La obesidad es una enfermedad prevalente en nuestro país, siendo sus causas multifactoriales, lo que la hace una enfermedad compleja, por esta razón el tratamiento es difícil de implementar, ya que sus inicios son en las etapas tempranas de la vida. Evaluamos alumnos de 21 escuelas municipalizadas de enseñanza general básica, rural y urbana pertenecientes a las 10 comunas de la novena región. La muestra fue de 275 sujetos pertenecientes a Kínder y primer año básico del año 2008, seguidos por dos años. Los resultados muestran una tendencia que indica un aumento en la prevalencia de obesidad en la muestra, siendo esta diferencia estadísticamente significativa, p= 0,000. Estos resultados demuestran que la obesidad va en aumento y que se necesitan más acciones para frenar esta enfermedad que aqueja a nuestra población en formación.


Assuntos
Criança , Índice de Massa Corporal , Obesidade/diagnóstico , Obesidade/epidemiologia , Chile/epidemiologia , Estudos Transversais/métodos , Pesos e Medidas Corporais/métodos , Estudantes
20.
J Exp Clin Cancer Res ; 30: 37, 2011 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-21477352

RESUMO

BACKGROUND: Cancer cells are known to secrete the stress molecules MICA and MICB that activate cytotoxicity by lymphocytes and NK cells through their NKG2D receptor as a mechanism of immunological defense. This work was undertaken to evaluate if cancer cells can also express this receptor as a possible mechanisms of depletion of MIC molecules and thus interfere with their immune recognition. METHODS: Myelomonocytic leukemic (TPH-1 and U-937) and cervical cancer (CALO and INBL) cell lines were evaluated by Western Blot, ELISA, flow cytometry and immunocytochemistry to evaluate their capacity to express and secrete MICA and MICB and to be induced to proliferate by these molecules as well as to express their receptor NKG2D. Statistical analysis was performed by two-way ANOVA for time course analysis and Student's t-test for comparison between groups. Values were considered significantly different if p < 0.05. RESULTS: THP-1 and U-937 produce and secrete the stress MICA and MICB as shown by Western Blot of lysed cells and by ELISA of their conditioned media. By Western Blot and flow cytometry we found that these cells also express the receptor NKG2D. When THP-1 and U-937 were cultured with recombinant MICA and MICB they exhibited a dose dependent induction for their proliferation. CALO and INBL also produce MICA and MICB and were induced to proliferate by these stress molecules. By Western Blot, flow cytometry and immunocytochemistry we also found that these cells express NKG2D. CONCLUSIONS: Our novel results that tumor cells can simultaneously secrete MIC molecules and express their receptor, and to be induced for proliferation by these stress molecules, and that tumor epithelial cells can also express the NKG2D receptor that was thought to be exclusive of NK and cytotoxic lymphocytes is discussed as a possible mechanism of immunological escape and of tumor growth induction.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Leucemia Mieloide/metabolismo , Subfamília K de Receptores Semelhantes a Lectina de Células NK/metabolismo , Neoplasias do Colo do Útero/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Meios de Cultivo Condicionados , Feminino , Antígenos de Histocompatibilidade Classe I/isolamento & purificação , Antígenos de Histocompatibilidade Classe I/farmacologia , Humanos , Leucemia Mieloide/patologia , Monócitos/metabolismo , Neoplasias do Colo do Útero/patologia
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