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1.
Bone ; 143: 115613, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32871273

RESUMO

Areal bone mineral density (aBMD) has a low sensitivity to identify women at high fracture risk. The FRAX algorithm, by combining several clinical risk factors, might improve fracture prediction compared to aBMD alone. Several micro-architectural and biomechanical parameters which can be measured by high-resolution peripheral quantitative computed tomography (HR-pQCT) are associated with fracture risk. HR-pQCT in combination or not with finite element analysis (FEA) may be used to improve bone strength prediction. Our aim was to assess whether HR-pQCT measurements (densities, cortical and trabecular microarchitecture, biomechanical proprieties assessed by FEA) had an added value in predicting fractures in a subgroup of women belonging to the Belgian FRISBEE cohort. One hundred nineteen women who sustained a fracture (aged 60 to 85 years) during the initial follow-up of our cohort had a radius and tibia examination by HR-pQCT and were compared with controls matched for their FRAX score at baseline. We found that low distal radius total (OR = 1.41 [1.07-1.86] per SD, p < 0.05) and trabecular densities (OR = 1.45 [1.10-1.90], p < 0.01), trabecular number (OR = 1.32 [1.01-1.72], p < 0.05), intra individual distribution of separation (OR = 0.73 [0.54-0.99], p < 0.05) as several FEA parameters were significantly associated with fractures. At the distal tibia, impaired cortical density (OR = 1.32 [1.03-1.70] per SD, p < 0.05) and thickness (OR = 1.29 [1.01-1.63], p < 0.05) and apparent modulus (OR = 1.30 [1.01-1.66], p < 0.05) were significantly correlated with fractures. A low ultra distal radial aBMD (UDR) measured at the time of HR-pQCT was significantly associated with fractures (OR = 1.67 [1.22-2.28], p < 0.01). Women from both groups were followed further after the realization of the HR-pQCT and 46 new fractures were registered. In this second part of the study, low UDR aBMD (OR = 1.66 [1.18-2.35], p < 0.01), total (OR = 1.48 [1.08-2.03], p < 0.05), cortical (OR = 1.40 [1.04-1.87], p < 0.05) and trabecular (OR = 1.37 [1.01-1.85], p < 0.05) densities or apparent modulus (OR = 1.49 [1.07-2.05], p < 0.05) at the radius were associated with a significant increase of fracture risk. At the tibia, only the cortical density was significantly associated with the fracture risk (OR = 1.34 [1.02-2.76], p < 0.05). These results confirm the interest of HR-pQCT measurements for the evaluation of fracture risk, also in women matched for their baseline FRAX score. They also highlight that UDR aBMD contains pertinent information.


Assuntos
Fraturas por Osteoporose , Absorciometria de Fóton , Densidade Óssea , Feminino , Humanos , Rádio (Anatomia)/diagnóstico por imagem , Tíbia/diagnóstico por imagem , Tomografia Computadorizada por Raios X
2.
FASEB J ; 34(12): 15718-15733, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33037689

RESUMO

Mammalian Cysteine-RIch Secretory Protein (CRISP) family includes four members present in sperm and reported to regulate Ca2+ channels and fertilization. Based on our previous observations using single knockouts models and suggesting the existence of functional compensation among CRISP proteins, we investigated their relevance for male fertility by generating multiple Crisp gene mutants by CRISPR/Cas9 technology. Whereas targeting of Crisp1 and Crisp3 yielded subfertile males with early embryo developmental defects, the same deletion in zygotes from fertile Crisp2-/- .Crisp4-/- mice led to the generation of both triple and quadruple knockout mice exhibiting a complete or severe disruption of male fertility due to a combination of sperm transport, fertilization, and embryo developmental defects linked to intracellular Ca2+ dysregulation. These observations reveal that CRISP proteins are essential for male fertility and organize in functional modules that contribute distinctly to fertility success, bringing insights into the mechanisms underlying functional redundancy/compensation in protein families and emphasizing the importance of generating multiple and not just single knockout which might be masking the true functional relevance of family genes.


Assuntos
Fertilidade/genética , Glicoproteínas de Membrana/genética , Proteínas de Plasma Seminal/genética , Animais , Sistemas CRISPR-Cas/genética , Cálcio/metabolismo , Feminino , Infertilidade Masculina/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Interações Espermatozoide-Óvulo/genética , Espermatozoides/metabolismo
3.
Osteoporos Int ; 31(7): 1377-1382, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32128600

RESUMO

Despite the availability of efficient drugs to prevent osteoporotic fractures, only a minority of women receives osteoporosis therapy after a fracture. The high treatment gap in our cohort consisted of unselected volunteer patients highlights the urgent need of additional education, especially for the medical profession, regarding the risk-benefit balance of treatment. INTRODUCTION: Despite the availability of efficient drugs to prevent osteoporotic fractures, only a minority of women receives osteoporosis therapy after a fracture, with a treatment gap around 80%. This can have dramatic consequences for patients and the healthcare systems. METHODS: In this study based on longitudinal data from the FRISBEE (Fracture RIsk Brussels Epidemiological Enquiry) cohort of 3560 volunteer women aged 60 to 85 years, we evaluated the 1-year treatment gap after a first major incident fragility fracture. RESULTS: There were 386 first validated fragility fractures, 285 major osteoporotic fractures (MOF) and 101 "other major" fractures. The rate of untreated patients was 85.0% (82.8% for MOF versus 91.0 % for "other major" fracture sites) (p = 0.04), with a lower rate for spine (70.5%) and hip (72.5%) versus shoulder (91.6%) and wrist (94.1%) (p < 0.0001). More specifically, the treatment gap for patients with osteoporosis, defined by a T-score < - 2.5 SD was 74.6% versus 76.5% for patients with osteoporosis defined by the presence of hip, shoulder, or spine fractures, independently of DXA results. When considering age groups, the rate of untreated women was 87.9% for women 60-70 years old, 88.2% between 70 and 80 years and 77.8% above 80 years (p = 0.03), with a greater difference between women who were younger or older than 80 years at inclusion: 88.1% versus 77.8% (p = 0.009). A diagnosis of osteoporosis (p = 0.01) and age (p = 0.03) were the only clinical risk factors (CRFs) significantly associated with treatment initiation. CONCLUSIONS: This study highlights the urgent need of additional education, especially for the medical profession, regarding the risk-benefit balance of treatment.


Assuntos
Osteoporose , Fraturas por Osteoporose , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Feminino , Humanos , Pessoa de Meia-Idade , Fraturas por Osteoporose/epidemiologia , Fraturas por Osteoporose/prevenção & controle , Estudos Prospectivos , Voluntários
4.
Phys Rev Lett ; 122(20): 208001, 2019 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-31172770

RESUMO

In the melt state at equilibrium, entangled nonconcatenated ring macromolecules adapt more compact conformations compared to their linear analogs and do not form an entanglement network. We show here that, when subjected to uniaxial stretching, they exhibit a unique response, which sets them apart from any other polymer. Remarkably, whereas both linear and ring polymers strain-harden, the viscosity of the rings increases dramatically (the melt thickens) at very low stretch rates due to the unraveling of their conformations along the stretching direction. At high rates, stretching leads to viscosity thinning similar to that of entangled linear polymers, albeit with subtle differences.

5.
Mol Psychiatry ; 23(2): 231-239, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-27956748

RESUMO

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder often accompanied by intellectual disability, language impairment and medical co-morbidities. The heritability of autism is high and multiple genes have been implicated as causal. However, most of these genes have been identified in de novo cases. To further the understanding of familial autism, we performed whole-exome sequencing on five families in which second- and third-degree relatives were affected. By focusing on novel and protein-altering variants, we identified a small set of candidate genes. Among these, a novel private missense C1143F variant in the second intracellular loop of the voltage-gated sodium channel NaV1.7, encoded by the SCN9A gene, was identified in one family. Through electrophysiological analysis, we show that NaV1.7C1143F exhibits partial loss-of-function effects, resulting in slower recovery from inactivation and decreased excitability in cultured cortical neurons. Furthermore, for the same intracellular loop of NaV1.7, we found an excess of rare variants in a case-control variant-burden study. Functional analysis of one of these variants, M932L/V991L, also demonstrated reduced firing in cortical neurons. However, although this variant is rare in Caucasians, it is frequent in Latino population, suggesting that genetic background can alter its effects on phenotype. Although the involvement of the SCN1A and SCN2A genes encoding NaV1.1 and NaV1.2 channels in de novo ASD has previously been demonstrated, our study indicates the involvement of inherited SCN9A variants and partial loss-of-function of NaV1.7 channels in the etiology of rare familial ASD.


Assuntos
Transtorno Autístico/genética , Canal de Sódio Disparado por Voltagem NAV1.7/genética , Transtorno do Espectro Autista/genética , Estudos de Casos e Controles , Família , Feminino , Humanos , Deficiência Intelectual/genética , Masculino , Mutação , Mutação de Sentido Incorreto/genética , Canal de Sódio Disparado por Voltagem NAV1.7/metabolismo , Neurônios/fisiologia , Fenótipo , Canais de Sódio/genética , Sequenciamento do Exoma
6.
Maturitas ; 106: 1-7, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29150162

RESUMO

OBJECTIVES: The estimation of fracture risk using clinical risk factors (CRFs) is of primary concern in osteoporosis management, but only some risk factors have been thoroughly evaluated and incorporated in predictive models. We have launched a large prospective study, the 'Fracture Risk Brussels Epidemiological Enquiry' (FRISBEE), to develop a new predictive model for osteoporotic fractures. The aims of this report are to describe the methodology of the FRISBEE study and to compare the distribution of CRFs in our cohort with those reported in other large studies. STUDY DESIGN: FRISBEE is a new study that prospectively evaluates a cohort of 3560 post-menopausal women (aged 60-85 years) followed yearly for the occurrence of fragility fractures. Multiple validated CRFs, densitometry (DXA) values and intake of medication were systematically registered at baseline. The distribution of the FRISBEE CRFs has been compared with the distributions of CRFs in the cohorts used to develop the FRAX® model as well as in more recent cohorts. For these recent cohorts, we focused on CRFs not included in FRAX®. RESULTS: The most frequently encountered CRFs used in FRAX® were a prior fragility fracture (27.1%) and a parental history of hip fracture (13.4%). The prevalence of some CRFs not integrated in FRAX® was relatively high, such as the use of proton pump inhibitors (20.8%) and a history of fall(s) (19.7%). The prevalence of many CRFs was quite variable between cohorts; for example, the prevalence of 'personal prior fragility fracture' ranged from 9% to 51%. CONCLUSION: We found considerable heterogeneity in the prevalence of CRFs between cohort studies. The impact of these differences on the predictive value of a particular CRF is unknown. We will construct a predictive model calibrated to the Belgian population. More importantly, the FRISBEE study should allow us to determine the predictive value of newly recognized CRFs in addition to the FRAX® algorithm to reliably estimate fracture risk.


Assuntos
Fraturas por Osteoporose/epidemiologia , Acidentes por Quedas , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Bélgica/epidemiologia , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa , Prevalência , Estudos Prospectivos , Fatores de Risco
7.
Mol Psychiatry ; 22(4): 595-604, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27431292

RESUMO

Motor execution and planning are tightly regulated by dopamine D1 and D2 receptors present in basal ganglia circuits. Although stimulation of D1 receptors is known to enhance motor function, the global effect of D2 receptor (D2R) stimulation or blockade remains highly controversial, with studies showing increasing, decreasing or no changes in motor activity. Moreover, pharmacological and genetic attempts to block or eliminate D2R have led to controversial results that questioned the importance of D2R in motor function. In this study, we generated an inducible Drd2 null-allele mouse strain that circumvented developmental compensations found in constitutive Drd2-/- mice and allowed us to directly evaluate the participation of D2R in spontaneous locomotor activity and motor learning. We have found that loss of D2R during adulthood causes severe motor impairments, including hypolocomotion, deficits in motor coordination, impaired learning of new motor routines and spontaneous catatonia. Moreover, severe motor impairment, resting tremor and abnormal gait and posture, phenotypes reminiscent of Parkinson's disease, were evident when the mutation was induced in aged mice. Altogether, the conditional Drd2 knockout model studied here revealed the overall fundamental contribution of D2R in motor functions and explains some of the side effects elicited by D2R blockers when used in neurological and psychiatric conditions, including schizophrenia, bipolar disorder, Tourette's syndrome, dementia, alcohol-induced delusions and obsessive-compulsive disorder.


Assuntos
Destreza Motora/fisiologia , Transtornos Parkinsonianos/metabolismo , Receptores de Dopamina D2/metabolismo , Técnicas de Ablação/métodos , Animais , Gânglios da Base/metabolismo , Corpo Estriado/metabolismo , Antagonistas de Dopamina/farmacologia , Humanos , Aprendizagem/efeitos dos fármacos , Locomoção/genética , Masculino , Camundongos , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Transtornos Parkinsonianos/fisiopatologia , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/fisiologia
8.
Genes Brain Behav ; 16(4): 449-461, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27870313

RESUMO

Opioid receptor antagonist naltrexone reduces alcohol consumption and relapse in both humans and rodents. This study investigated whether hypothalamic proopiomelanocortin (POMC) neurons (producing beta-endorphin and melanocortins) play a role in alcohol drinking behaviors. Both male and female mice with targeted deletion of two neuronal Pomc enhancers nPE1 and nPE2 (nPE-/-), resulting in hypothalamic-specific POMC deficiency, were studied in short-access (4-h/day) drinking-in-the-dark (DID, alcohol in one bottle, intermittent access (IA, 24-h cycles of alcohol access every other day, alcohol vs. water in a two-bottle choice) and alcohol deprivation effect (ADE) models. Wild-type nPE+/+ exposed to 1-week DID rapidly established stable alcohol drinking behavior with more intake in females, whereas nPE-/- mice of both sexes had less intake and less preference. Although nPE-/- showed less saccharin intake and preference than nPE+/+, there was no genotype difference in sucrose intake or preference in the DID paradigm. After 3-week IA, nPE+/+ gradually escalated to high alcohol intake and preference, with more intake in females, whereas nPE-/- showed less escalation. Pharmacological blockade of mu-opioid receptors with naltrexone reduced intake in nPE+/+ in a dose-dependent manner, but had blunted effects in nPE-/- of both sexes. When alcohol was presented again after 1-week abstinence from IA, nPE+/+ of both sexes displayed significant increases in alcohol intake (ADE or relapse-like drinking), with more pronounced ADE in females, whereas nPE-/- did not show ADE in either sex. Our results suggest that neuronal POMC is involved in modulation of alcohol 'binge' drinking, escalation and 'relapse', probably via hypothalamic-mediated mechanisms, with sex differences.


Assuntos
Insuficiência Adrenal/metabolismo , Consumo de Bebidas Alcoólicas/metabolismo , Obesidade/metabolismo , Pró-Opiomelanocortina/deficiência , Insuficiência Adrenal/genética , Consumo de Bebidas Alcoólicas/tratamento farmacológico , Consumo de Bebidas Alcoólicas/genética , Animais , Etanol/farmacologia , Feminino , Genótipo , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Masculino , Camundongos , Camundongos Knockout , Naltrexona/farmacologia , Obesidade/genética , Pró-Opiomelanocortina/genética , Pró-Opiomelanocortina/metabolismo
9.
Med. infant ; 23(1): 8-12, Marzo 2016. tab, ilus
Artigo em Espanhol | LILACS | ID: biblio-881698

RESUMO

Las concentraciones de calcio (Ca), fósforo (P) y fosfatasa alcalina sérica (FAL) son extensamente evaluados en pediatría. La aplicación del procedimiento recomendado por la International Federation of Clinical Chemistry (IFCC) para evaluar FAL en el equipo Cobas 501 de Roche, requirió de una reevaluación del Intervalo de referencia (IR) en nuestra población pediátrica. El método indirecto de Hoffmann con la modificaciones propuestas por Katayev et al. provee un mecanismo para estimar IR en poblaciones de difícil estudio como la pediátrica. A partir de trabajar con nuestra base de datos nos propusimos fijar IR para Ca., P, y FAL discriminados por edad y sexo (en el caso de la FAL) en nuestra población pediátrica. Se utilizaron los resultados de un año de la base de datos del hospital de sujetos entre 0 y 18 años El total de los sujetos analizados fue de 13.906 pacientes para Calcio 14.790 para fósforo y 6.333 para FAL. En FAL encontramos dimorfismo sexual en los grupos de 7 a 9, 10 a 12, 13 a 15 y 16 a 18 años con una diferencia significativa (p<0,0001). Los IR fueron calculados con los procedimientos recomendados por edad y género, los analitos Ca y P no presentaron diferencias por sexo y las diferencias por edad no fueron significativas aunque sí resultaron útiles para fijar los rangos frente a la FAL. El método de Hoffmann modificado es útil para la evaluación de poblaciones con dificultades para su estudio como la pediátrica (AU)


Serum calcium (Ca), phosphorus (P), and alkaline phosphatase (AP) levels are broadly assessed in pediatrics. The procedure recommended by the International Federation of Clinical Chemistry (IFCC) for measuring AP in the Cobas 501 of Roche required reassessment of the reference interval (RI) in our pediatric population. The indirect method of Hoffmann with modifications proposed by Katayev et al. provides a mechanism to estimate the RI in difficult-to-study populations, such as children. Based on our data base, we aimed at determining the RI for Ca, P, and AP divided by age and sex (in the case of AP) in our pediatric population. One-year results of the hospital data base of subjects between 0 and 18 years of age were used. A total of 13.906 patients were analyzed for Ca, 14,790 for Ph, and 6,333 for AP. For AP sexual dimorphism was found in the age groups 7 to 9, 10 to 12, 13 to 15, and 16 to 18 years with a significant difference (p<0.0001). RIs were calculated with recommendations for age and sex. The analytes Ca and P did not show differences according to age, and differences according to sex were not significant although they were useful to determine ranges relative to AP. The modified Hoffmann method is useful in the evaluation of difficult-to-study populations, such as children (AU)


Assuntos
Humanos , Recém-Nascido , Lactente , Pré-Escolar , Criança , Adolescente , Fosfatase Alcalina , Cálcio , Técnicas de Laboratório Clínico , Fósforo , Valores de Referência , Caracteres Sexuais , Serviços de Laboratório Clínico
11.
Cancer Gene Ther ; 22(7): 360-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26182912

RESUMO

The ability to genetically modify T cells is a critical component to many immunotherapeutic strategies and research studies. However, the success of these approaches is often limited by transduction efficiency. As retroviral vectors require cell division for integration, transduction efficiency is dependent on the appropriate activation and culture conditions for T cells. Naive CD8(+) T cells, which are quiescent, must be first activated to induce cell division to allow genetic modification. To optimize this process, we activated mouse T cells with a panel of different cytokines, including interleukin-2 (IL-2), IL-4, IL-6, IL-7, IL-12, IL-15 and IL-23, known to act on T cells. After activation, cytokines were removed, and activated T cells were retrovirally transduced. We found that IL-12 preconditioning of mouse T cells greatly enhanced transduction efficiency, while preserving function and expansion potential. We also observed a similar transduction-enhancing effect of IL-12 preconditioning on human T cells. These findings provide a simple method to improve the transduction efficiencies of CD8(+) T cells.


Assuntos
Linfócitos T CD8-Positivos/fisiologia , Interleucina-12/farmacologia , Vírus da Leucemia Murina de Moloney/genética , Transdução Genética , Animais , Proteína 3 do Linfoma de Células B , Linfócitos T CD8-Positivos/efeitos dos fármacos , Células Cultivadas , Expressão Gênica , Humanos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Med. infant ; 20(1): 22-26, mar. 2013. graf, tab
Artigo em Espanhol | LILACS | ID: lil-774401

RESUMO

El mercurio (Hg) es un tóxico metálico, ubícuo, con alto impacto en la salud humana y en los ecosistemas. Los efectos adversos sobre la población infantil dependen de la vulnerabilidad de este grupo etario. La toxicidad se manifiesta principalmente por sus conocidos efectos sobre el neurodesarrollo a partir del momento de la concepción hasta la adolescencia. El sector de la salud es una de las principales fuentes de emisión de Hg a nivel mundial. El Hg está presente en gran cantidad de insumos y dispositivos de uso médico en los establecimientos de salud. La rotura y el descarte de estos insumos producen pequeños derrames ocasionando así que este sector contribuya no sólo a alterar la calidad del ambiente laboral sino también, la carga global del tóxico. Un grupo multidisciplinario de profesionales de diferentes áreas comprometido en el cuidado del medio ambiente y la salud infantil trabajó para reemplazar el uso del mercurio en el Hospital Garrahan. Se describe el desarrollo de este proceso en cinco etapas: 1) Diagnóstico; 2) Concientización del personal; 3) Segregación del HG; 4) Reemplazo de insumos; 5) Monitoreo continuo.


Assuntos
Humanos , Masculino , Feminino , Criança , Hospitais Pediátricos , Hospitais Públicos/normas , Intoxicação por Mercúrio/diagnóstico , Intoxicação por Mercúrio/prevenção & controle , Mercúrio , Mercúrio/efeitos adversos , Argentina , Monitoramento Ambiental/métodos , Monitoramento Ambiental/prevenção & controle
13.
Med. infant ; 20(1): 22-26, mar. 2013. graf, tab
Artigo em Espanhol | BINACIS | ID: bin-132567

RESUMO

El mercurio (Hg) es un tóxico metálico, ubícuo, con alto impacto en la salud humana y en los ecosistemas. Los efectos adversos sobre la población infantil dependen de la vulnerabilidad de este grupo etario. La toxicidad se manifiesta principalmente por sus conocidos efectos sobre el neurodesarrollo a partir del momento de la concepción hasta la adolescencia. El sector de la salud es una de las principales fuentes de emisión de Hg a nivel mundial. El Hg está presente en gran cantidad de insumos y dispositivos de uso médico en los establecimientos de salud. La rotura y el descarte de estos insumos producen pequeños derrames ocasionando así que este sector contribuya no sólo a alterar la calidad del ambiente laboral sino también, la carga global del tóxico. Un grupo multidisciplinario de profesionales de diferentes áreas comprometido en el cuidado del medio ambiente y la salud infantil trabajó para reemplazar el uso del mercurio en el Hospital Garrahan. Se describe el desarrollo de este proceso en cinco etapas: 1) Diagnóstico; 2) Concientización del personal; 3) Segregación del HG; 4) Reemplazo de insumos; 5) Monitoreo continuo


Assuntos
Humanos , Masculino , Feminino , Criança , Mercúrio , Mercúrio/efeitos adversos , Intoxicação por Mercúrio/diagnóstico , Intoxicação por Mercúrio/prevenção & controle , Hospitais Pediátricos , Monitoramento Ambiental/métodos , Monitoramento Ambiental/prevenção & controle , Argentina
14.
Clin Exp Immunol ; 171(3): 319-29, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23379439

RESUMO

Diabetes is associated with an increased risk of death from infectious disease. Hyperglycaemia has been identified as the main factor contributing to the development of diseases associated with diabetes mellitus. However, experimental evidence indicates individual susceptibility to develop complications of diabetes. In this context, the aim of this work was to study the immune response in a streptozotocin-induced type 1 diabetes in two mouse strains: BALB/cByJ and C57Bl/6J. The participation of hyperglycaemia and oxidative stress was also analysed. Diabetic BALB/cByJ mice showed a decrease in both the in-vivo and in-vitro immune responses, whereas diabetic C57Bl/6J mice had higher blood glucose but exhibited no impairment of the immune response. The influence of hyperglycaemia over the immune response was evaluated by preincubation of lymphocytes from normal mice in a high glucose-containing medium. T and B cells from BALB/cByJ mice showed a decrease in cell viability and mitogen-stimulated proliferation and an increase in apoptosis induction. An increase in oxidative stress was implicated in this deleterious effect. These parameters were not affected in the T and B lymphocytes from C57Bl/6J mice. In conclusion, BALB/cByJ mice were sensitive to the deleterious effect of hyperglycaemia, while C57BL/6J were resistant. Although an extrapolation of these results to clinical conditions must be handled with caution, these results highlight the need to contemplate the genetic background to establish models to study the deleterious effect of diabetes in order to understand phenotypical variations that are of clinical importance in the treatment of patients.


Assuntos
Diabetes Mellitus Experimental/imunologia , Hiperglicemia/imunologia , Estresse Oxidativo , Animais , Glicemia/análise , Diabetes Mellitus Experimental/metabolismo , Feminino , Glutationa/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Estreptozocina
15.
Mol Psychiatry ; 17(6): 650-62, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21844870

RESUMO

Polymorphic variants of the dopamine D(4) receptor have been consistently associated with attention-deficit hyperactivity disorder (ADHD). However, the functional significance of the risk polymorphism (variable number of tandem repeats in exon 3) is still unclear. Here, we show that whereas the most frequent 4-repeat (D(4.4)) and the 2-repeat (D(4.2)) variants form functional heteromers with the short isoform of the dopamine D(2) receptor (D(2S)), the 7-repeat risk allele (D(4.7)) does not. D(2) receptor activation in the D(2S)-D(4) receptor heteromer potentiates D(4) receptor-mediated MAPK signaling in transfected cells and in the striatum, which did not occur in cells expressing D(4.7) or in the striatum of knockin mutant mice carrying the 7 repeats of the human D(4.7) in the third intracellular loop of the D(4) receptor. In the striatum, D(4) receptors are localized in corticostriatal glutamatergic terminals, where they selectively modulate glutamatergic neurotransmission by interacting with D(2S) receptors. This interaction shows the same qualitative characteristics than the D(2S)-D(4) receptor heteromer-mediated mitogen-activated protein kinase (MAPK) signaling and D(2S) receptor activation potentiates D(4) receptor-mediated inhibition of striatal glutamate release. It is therefore postulated that dysfunctional D(2S)-D(4.7) heteromers may impair presynaptic dopaminergic control of corticostriatal glutamatergic neurotransmission and explain functional deficits associated with ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/genética , Multimerização Proteica , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D4/metabolismo , Animais , Células CHO , Corpo Estriado/metabolismo , Cricetinae , Técnicas de Introdução de Genes/métodos , Ácido Glutâmico/metabolismo , Células HEK293 , Humanos , Técnicas In Vitro , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neurônios/metabolismo , Transdução de Sinais , Transfecção/métodos
16.
Stress ; 13(5): 384-91, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20666647

RESUMO

Stress, an important aspect of modern life, has long been associated with an altered homeostatic state. Little is known about the effect of the life stress on the outcome of diabetes mellitus, especially related to the higher risk of infections. Here, we evaluate the effects of chronic mild stress (CMS) exposure on the evolution of type I diabetes induced by streptozotocin administration in BALB/c mice. Exposure of diabetic mice to CMS resulted in a significant reduction of survival and a sustained increase in blood glucose values. Concerning the immune response, chronic stress had a differential effect in mice with diabetes with respect to controls, showing a marked decrease in both T- and B-cell proliferation. No correlation was found between splenic catecholamine or circulating corticosterone levels and the proliferative response. However, a significant negative correlation was found between glucose levels and concanavalin A- and lipopolysaccharide-stimulated proliferative responses of T and B cells. A positive correlation between blood glucose and splenic catecholamine concentrations was found in diabetic mice but not in controls subjected to CMS. Hence, the present report shows that diabetic mice show a worse performance in immune function after stress exposure, pointing to the importance of considering life stress as a risk factor for patients with diabetes.


Assuntos
Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/psicologia , Hormônios/fisiologia , Hiperglicemia/sangue , Estresse Psicológico/imunologia , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Glicemia/metabolismo , Catecolaminas/sangue , Células Cultivadas , Doença Crônica , Corticosterona/sangue , Feminino , Privação de Alimentos , Camundongos , Camundongos Endogâmicos BALB C , Mitógenos/farmacologia , Análise de Sobrevida , Linfócitos T/efeitos dos fármacos , Linfócitos T/imunologia , Privação de Água/fisiologia
17.
J Psychopharmacol ; 24(6): 897-904, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19282420

RESUMO

Methylphenidate (MP) and amphetamine (AMPH) are the most frequently prescribed medications for the treatment of attention-deficit/hyperactivity disorder (ADHD). Both drugs are believed to derive their therapeutic benefit by virtue of their dopamine (DA)-enhancing effects, yet an explanation for the observation that some patients with ADHD respond well to one medication but not to the other remains elusive. The dopaminergic effects of MP and AMPH are also thought to underlie their reinforcing properties and ultimately their abuse. Polymorphisms in the human gene that codes for the DA D4 receptor (D4R) have been repeatedly associated with ADHD and may correlate with the therapeutic as well as the reinforcing effects of responses to these psychostimulant medications. Conditioned place preference (CPP) for MP, AMPH and cocaine were evaluated in wild-type (WT) mice and their genetically engineered littermates, congenic on the C57Bl/6J background, that completely lack D4Rs (knockout or KO). In addition, the locomotor activity in these mice during the conditioning phase of CPP was tested in the CPP chambers. D4 receptor KO and WT mice showed CPP and increased locomotor activity in response to each of the three psychostimulants tested. D4R differentially modulates the CPP responses to MP, AMPH and cocaine. While the D4R genotype affected CPP responses to MP (high dose only) and AMPH (low dose only) it had no effects on cocaine. Inasmuch as CPP is considered an indicator of sensitivity to reinforcing responses to drugs these data suggest a significant but limited role of D4Rs in modulating conditioning responses to MP and AMPH. In the locomotor test, D4 receptor KO mice displayed attenuated increases in AMPH-induced locomotor activity whereas responses to cocaine and MP did not differ. These results suggest distinct mechanisms for D4 receptor modulation of the reinforcing (perhaps via attenuating dopaminergic signalling) and locomotor properties of these stimulant drugs. Thus, individuals with D4 receptor polymorphisms might show enhanced reinforcing responses to MP and AMPH and attenuated locomotor response to AMPH.


Assuntos
Anfetamina/farmacologia , Cocaína/farmacologia , Condicionamento Psicológico/efeitos dos fármacos , Metilfenidato/farmacologia , Atividade Motora/efeitos dos fármacos , Receptores de Dopamina D4/genética , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Condicionamento Psicológico/fisiologia , Inibidores da Captação de Dopamina/farmacologia , Comportamento Exploratório/efeitos dos fármacos , Comportamento Exploratório/fisiologia , Genótipo , Masculino , Camundongos , Camundongos Knockout , Atividade Motora/genética , Distribuição Aleatória
18.
Clin Otolaryngol ; 34(5): 460-6, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19793279

RESUMO

OBJECTIVES: Optical coherence tomography, an imaging modality using near-infrared light, produces cross-sectional tissue images with a lateral pixel resolution of 10 microm. However, normative data is first needed on epithelial thickness for lesion characterisation, and, to date, little exists. The purpose of our study is to measure normal laryngeal epithelial thickness by in vivo optical coherence tomography, and compare these values to those obtained from fixed ex-vivo laryngectomy specimens. DESIGN AND SETTING: Prospective at a single medical center in California, United States. PARTICIPANTS: A total of 116 patients undergoing operative endoscopy. MAIN OUTCOME MEASURES: Optical coherence tomography images of clinically normal laryngeal subsites were selected. Calibrated measurements of epithelial thickness at various laryngeal subsites were recorded. Measurements of epithelial thickness from corresponding areas were obtained using optical micrometry on histologically normal regions of 15 total laryngectomy specimens. Descriptive statistics were performed. RESULTS: Mean epithelial optical coherence tomography thicknesses were: true vocal cords (81 microm), false vocal cords (78 microm), subglottis (61 microm), aryepiglottic folds (111 microm), laryngeal epiglottis (116 microm) and lingual epiglottis (170 microm). Epithelial thicknesses in fixed tissues were: true vocal cords (103 microm), false vocal cords (79 microm), aryepiglottic folds (205 microm) subglottis (61 microm), laryngeal epiglottis (38 microm) and lingual epiglottis (130 microm). CONCLUSIONS: Optical coherence tomography does not have the artifacts associated with conventional histologic techniques. The inevitable development of office-based optical coherence tomography devices will increase the precision of laryngeal measurements and contribute to the clinical application of this technology in diagnosing laryngeal disease.


Assuntos
Neoplasias Laríngeas/patologia , Laringe/patologia , Idoso , Feminino , Humanos , Neoplasias Laríngeas/cirurgia , Laringectomia , Laringoscopia , Laringe/cirurgia , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência Óptica
19.
Cancer Gene Ther ; 16(2): 171-83, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18690205

RESUMO

Adoptive T-cell therapy is clinically efficacious in the treatment of select cancers. However, it is often difficult to obtain adequate numbers of tumor-specific T cells for therapy. One method for overcoming this limitation is to generate tumor-specific T cells by retrovirally mediated T-cell-receptor (TCR) gene transfer. However, despite instances of therapeutic success, major obstacles remain, including attaining the survival of retrovirally modified T cells in vivo as well as inducing long-term and multi-gene retroviral expression. Using a murine model of adoptively transferred retrovirally modified CD8(+) T cells, where antitumor immunity was dependent on sustained, multigene expression, we found that in vitro assays are poor indicators of in vivo efficacy. Despite persisting for over 9 months in a nonlymphopenic environment, genetically modified T cells exhibited discordant retrovirally mediated gene expression in vivo not readily evident from initial in vitro assays. In particular, one of the two TCR subunit genes necessary for antigen specificity was selectively lost in vivo. As this discordant gene expression was associated with the loss of antitumor immunity, consideration of these findings may provide guidance in the design, evaluation and application of retroviral vectors for use in the treatment of cancer and other human disease.


Assuntos
Regulação para Baixo , Neoplasias/imunologia , Receptores de Antígenos de Linfócitos T/genética , Retroviridae/metabolismo , Subpopulações de Linfócitos T/metabolismo , Animais , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Regulação Neoplásica da Expressão Gênica , Vetores Genéticos/genética , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias/metabolismo , Retroviridae/genética , Transgenes/genética
20.
J Clin Immunol ; 29(1): 38-45, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18594952

RESUMO

INTRODUCTION: In the present study, we examined the levels of the pro-inflammatory cytokine IL-18 and its natural inhibitor, the IL-18 binding protein (IL-18BP), in sera of Wegener's granulomatosis (WG) patients at various stages of the disease. PATIENTS AND METHODS: Sera from eight consecutive biopsy-proven systemic WG patients (four men and four women; age at diagnosis 58.4 +/- 13.8 years) were obtained longitudinally with a follow-up period of 55.2 +/- 30 months. Sera obtained from 50 healthy subjects were used as controls. RESULTS AND DISCUSSION: Serum levels of IL-18, IL-18BP, and free IL-18 obtained during an active phase of the disease (Birmingham Vasculitis Activity Score, BVAS > 10) were more than twofold higher than levels in the same patients during inactive disease stages (BVAS < 5; P < 0.002; P < 0.006, and P < 0.03 for IL-18, IL-18BP, and free IL-18, respectively). During inactive stages, the levels of these markers were comparable to those of healthy controls. The elevated levels of IL-18 and IL-18BP in sera during active stages of disease suggest a possible role in the pathogenesis and course of the WG. CONCLUSION: Despite the elevated IL-18BP levels during active disease, free IL-18 remained higher than in the inactive disease stages, suggesting a potential benefit of administration of exogenous IL-18BP as a novel therapeutic approach for active WG.


Assuntos
Granulomatose com Poliangiite/sangue , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Interleucina-18/sangue , Idoso , Biomarcadores/sangue , Feminino , Seguimentos , Granulomatose com Poliangiite/diagnóstico , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade
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