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1.
Rev Neurol ; 72(10): 343-351, 2021 May 16.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-33978228

RESUMO

INTRODUCTION AND AIM: Perinatal transmission of human immunodeficiency virus (PHIV) is considered a chronic disease that has highlighted several cognitive deficits. From birth to early adulthood, cognition is known to play a fundamental role. However, although neurocognitive processes associated with PHIV have been extensively described by psychometric testing, data is scarce on neural activity from functional magnetic resonance imaging (fMRI) which provides in vivo physiological information. SUBJECTS AND METHODS: We studied described impaired cognitive processes using fMRI on a group of PHIV adolescents with good immunovirological indications and healthy matched controls. Psychological status and neurocognitive functions were also assessed. RESULTS: There were no significant differences between HIV+ and HIV- groups, either on neurocognitive testing nor in fMRI activity for phonological fluency tasks. Prolonged duration of cART was positively associated with greater brain activity in left inferior frontal gyrus (LIFG) which could indicate functional compensation. CONCLUSIONS: These results suggest that neural activity through fMRI in PHIV adolescents with good daily functioning and good immunovirological control may be similar to their peers.


TITLE: Actividad cerebral en jóvenes infectados por el virus de la inmunodeficiencia humana por transmisión vertical: estudio piloto de resonancia magnética funcional.Introducción y objetivos. La infección por el virus de la inmunodeficiencia humana de transmisión vertical (VIH-TV) constituye una enfermedad crónica que puede asociar múltiples alteraciones cognitivas que pueden influenciar el desarrollo de estos pacientes desde la infancia a la vida adulta. Sin embargo, aunque las alteraciones neurocognitivas vinculadas al VIH-TV están ampliamente descritas y valoradas mediante pruebas psicométricas, no existen apenas estudios de actividad neuronal medida a través de la resonancia magnética funcional (RMf). Sujetos y métodos. Analizar la utilidad de la RMf a través de la realización de tareas motoras y de fluidez verbal en un grupo de adolescentes y jóvenes con VIH-TV con buen control inmunovirológico y compararlo con un grupo control negativo de características similares. Se evaluaron también alteraciones psicológicas y funciones neurocognitivas. Resultados. No se encontraron diferencias significativas entre el grupo VIH+ y el grupo control para las tareas ejecutadas durante la RMf ni en la evaluación neurocognitiva. Un mayor tiempo de terapia combinada antirretroviral se asoció de forma directa con una mayor actividad en el giro frontal inferior izquierdo, lo cual podría indicar una posible compensación funcional. Conclusiones. Estos resultados sugieren que la actividad neuronal medida a través de la RMf en adolescentes con VIH-TV y buen control inmunovirológico es similar a la de sus pares.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Infecções por HIV/fisiopatologia , Transmissão Vertical de Doenças Infecciosas , Imageamento por Ressonância Magnética , Adolescente , Adulto , Disfunção Cognitiva/etiologia , Estudos Transversais , Feminino , Infecções por HIV/complicações , Infecções por HIV/terapia , Infecções por HIV/transmissão , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Adulto Jovem
2.
Rev. neurol. (Ed. impr.) ; 72(10): 343-351, May 16, 2021. tab, ilus, graf
Artigo em Inglês, Espanhol | IBECS | ID: ibc-227878

RESUMO

Introducción y objetivos: La infección por el virus de la inmunodeficiencia humana de transmisión vertical (VIH-TV) constituye una enfermedad crónica que puede asociar múltiples alteraciones cognitivas que pueden influenciar el desarrollo de estos pacientes desde la infancia a la vida adulta. Sin embargo, aunque las alteraciones neurocognitivas vinculadas al VIH-TV están ampliamente descritas y valoradas mediante pruebas psicométricas, no existen apenas estudios de actividad neuronal medida a través de la resonancia magnética funcional (RMf). Sujetos y métodos:Analizar la utilidad de la RMf a través de la realización de tareas motoras y de fluidez verbal en un grupo de adolescentes y jóvenes con VIH-TV con buen control inmunovirológico y compararlo con un grupo control negativo de características similares. Se evaluaron también alteraciones psicológicas y funciones neurocognitivas. Resultados: No se encontraron diferencias significativas entre el grupo VIH+ y el grupo control para las tareas ejecutadas durante la RMf ni en la evaluación neurocognitiva. Un mayor tiempo de terapia combinada antirretroviral se asoció de forma directa con una mayor actividad en el giro frontal inferior izquierdo, lo cual podría indicar una posible compensación funcional. Conclusiones: Estos resultados sugieren que la actividad neuronal medida a través de la RMf en adolescentes con VIH-TV y buen control inmunovirológico es similar a la de sus pares.(AU)


Introduction and aim: Perinatal transmission of human immunodeficiency virus (PHIV) is considered a chronic disease that has highlighted several cognitive deficits. From birth to early adulthood, cognition is known to play a fundamental role. However, although neurocognitive processes associated with PHIV have been extensively described by psychometric testing, data is scarce on neural activity from functional magnetic resonance imaging (fMRI) which provides in vivo physiological information. Subjects and methods: We studied described impaired cognitive processes using fMRI on a group of PHIV adolescents with good immunovirological indications and healthy matched controls. Psychological status and neurocognitive functions were also assessed. Results: There were no significant differences between HIV+ and HIV– groups, either on neurocognitive testing nor in fMRI activity for phonological fluency tasks. Prolonged duration of cART was positively associated with greater brain activity in left inferior frontal gyrus (LIFG) which could indicate functional compensation. Conclusions: These results suggest that neural activity through fMRI in PHIV adolescents with good daily functioning and good immunovirological control may be similar to their peers.(AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Transmissão Vertical de Doenças Infecciosas , HIV/fisiologia , Transtornos Neurocognitivos , Neuroimagem , Disfunção Cognitiva , Qualidade de Vida , Neurologia , Doenças do Sistema Nervoso , Espectroscopia de Ressonância Magnética , Projetos Piloto , Estudos Transversais , Estudos Prospectivos
3.
Heliyon ; 6(4): e03600, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32368635

RESUMO

Delayed neurodevelopment is a common outcome in perinatally HIV-infected children. Our aim was to assess the intellectual profile of our cohort, considering both the infection and socio-environmental related variables. A cross-sectional cohort study was undertaken at seven major hospitals in Spain belonging to the CoRISpeS cohort (n = 97). Patients were followed up according to a standard protocol. Intellectual measures, psychosocial profile and HIV infection-related data have been analysed. The average patient age was 15 years. The median CD4 cell percentage was 35% (1,59). Viral load was undetectable in 80% of the patients and 27% were on AIDS category; 38% of whom had encephalopathy. The average composite score of both crystallized intelligence (CI) and intelligence quotient (IQ) for the cohort was lower than that of the general population (p < 0.001). Results revealed a significant difference of 38% between crystallized and fluid intelligence. There was a clear association between IQ and age of diagnosis (p = 0.022); CI and CDC classification (p = 0.035), CD4 count (p = 0.011) and CD4 nadir (p = 0.001). Higher parental education was associated with better performance across all intelligence scales (p < 0.002). A regression model showed that CI was influenced by the academic level of caregivers (p = 0.002), age at start of cART (p = 0.050) and primary language (p = 0.058). Findings revealed significant differences in verbal and non-verbal intellectual scales resulting in a misleading IQ Composite score. Crystallized intelligence demonstrated the highest level of impairment despite adequate treatment and good immunovirological status, while fluid intelligence results were average. Caregiver level of education was the strongest factor across all intelligence measures.

4.
Int J Tuberc Lung Dis ; 24(3): 303-309, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-32228760

RESUMO

BACKGROUND: Tuberculosis (TB) is the leading opportunistic infection in children with human immunodeficiency virus (HIV), but is uncommon in low prevalence regions. We aim to describe the changing epidemiology and clinical presentation of TB-HIV co-infection in a cohort of HIV-infected children in Spain.METHODS: Children diagnosed with TB between 1995 and 2016 in the paediatric HIV cohort were identified. The incidence and clinical presentation were compared in three periods: 1995-1999 (P1, before initiation of combined antiretroviral therapy, cART), 2000-2009 (P2, increase in immigration), and 2010-2016 (P3, decrease in immigration).RESULTS: We included 29 TB cases among 1183 children aged <18 years (2.4%, 243/100 000 person-years). The proportion was stable in P1 and P2 (1.3%), but decreased in P3 (0.8%). The median age at TB diagnosis was 6.4 years (IQR 4-10.6); most children in P3 were aged >10 years (20% vs. 23.1% vs. 83.3%, P = 0.01). TB was diagnosed at HIV presentation in 11/29 children (37.9%). Foreign-born children accounted for respectively 0%, 8% and 67% of the total number of children in each period (P ≤ 0.0001). One third had extrapulmonary TB; four children died (13.8%).CONCLUSION: In our cohort, the incidence of TB-HIV co-infection decreased with decline in immigration. In regions with adequate cART coverage and low TB transmission, paediatric TB-HIV coinfection is uncommon, but associated with significant morbidity. Strategies for TB surveillance, diagnosis and treatment in this vulnerable population should be reinforced.


Assuntos
Coinfecção , Infecções por HIV , Tuberculose , Adolescente , Criança , Estudos de Coortes , Coinfecção/epidemiologia , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Estudos Retrospectivos , Espanha/epidemiologia , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia
5.
Langmuir ; 32(27): 6794-805, 2016 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-27281114

RESUMO

Understanding calcium silicate hydrates (CSHs) is of paramount importance for understanding the behavior of cement materials because they control most of the properties of these man-made materials. The atomic scale water content and structure have a major influence on their properties, as is analogous with clay minerals, and we should assess these. Here, we used a multiple analytical approach to quantify water distribution in CSH samples and to determine the relative proportions of water sorbed on external and internal (interlayer) surfaces. Water vapor isotherms were used to explain the water distribution in the CSH microstructure. As with many layered compounds, CSHs have external and internal (interlayer) surfaces displaying multilayer adsorption of water molecules on external surfaces owing to the hydrophilic surfaces. Interlayer water was also quantified from water vapor isotherm, X-ray diffraction (XRD), and thermal gravimetric analyses (TGA) data, displaying nonreversible swelling/shrinkage behavior in response to drying/rewetting cycles. From this quantification and balance of water distribution, we were able to explain most of the widely dispersed data already published according to the various relative humidity (RH) conditions and measurement techniques. Stoichiometric formulas were proposed for the different CSH samples analyzed (0.6 < Ca/Si < 1.6), considering the interlayer water contribution.

6.
Clin Microbiol Infect ; 21(6): 605.e1-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25680310

RESUMO

Drug resistance mutations compromise the success of antiretroviral treatment in human immunodeficiency virus type 1 (HIV-1)-infected children. We report the virologic and clinical follow-up of the Madrid cohort of perinatally HIV-infected children and adolescents after the selection of triple-class drug-resistant mutations (TC-DRM). We identified patients from the cohort carrying HIV-1 variants with TC-DRM to nucleoside reverse transcriptase inhibitors, nonnucleoside reverse transcriptase inhibitors and protease inhibitors according to IAS-USA-2013. We recovered pol sequences or resistance profiles from 2000 to 2011 and clinical-immunologic-virologic data from the moment of TC-DRM detection until December 2013. Viruses harbouring TC-DRM were observed in 48 (9%) of the 534 children and adolescents from 2000 to 2011, rising to 24.4% among those 197 with resistance data. Among them, 95.8% were diagnosed before 2003, 91.7% were Spaniards, 89.6% carried HIV-1-subtype B and 75% received mono/dual therapy as first regimen. The most common TC-DRM present in ≥50% of them were D67NME, T215FVY, M41L and K103N (retrotranscriptase) and L90M (protease). The susceptibility to darunavir, tipranavir, etravirine and rilpivirine was 67.7%, 43.7%, 33.3% and 33.3%, respectively, and all reported high resistance to didanosine, abacavir and nelfinavir. Despite the presence of HIV-1 resistance mutations to the three main antiretroviral families in our paediatric cohort, some drugs maintained their susceptibility, mainly the new protease inhibitors (tipranavir and darunavir) and nonnucleoside reverse transcriptase inhibitors (etravirine and rilpivirine). These data will help to improve the clinical management of HIV-infected children with triple resistance in Spain.


Assuntos
Antirretrovirais/farmacologia , Antirretrovirais/uso terapêutico , Farmacorresistência Viral Múltipla , Infecções por HIV/patologia , Infecções por HIV/virologia , HIV-1/efeitos dos fármacos , HIV-1/isolamento & purificação , Adolescente , Adulto , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Seguimentos , Técnicas de Genotipagem , HIV-1/genética , Humanos , Lactente , Recém-Nascido , Masculino , Testes de Sensibilidade Microbiana , Espanha , Adulto Jovem
7.
Chromosome Res ; 20(7): 875-87, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23143649

RESUMO

It is well established that chromosomes occupy distinct positions within the interphase nuclei, conferring a potential functional implication to the genome. In addition, alterations in the nuclear organisation patterns have been associated with disease phenotypes (e.g. cancer or laminopathies). The human sperm is the smallest cell in the body with specific DNA packaging and the mission of delivering the paternal genome to the oocyte during fertilisation. Studies of nuclear organisation in the sperm have postulated nonrandom chromosome position and have proposed a chromocentre model with the centromeres facing toward the interior and the telomeres toward the periphery of the nucleus. Most studies have assessed the nuclear address in the sperm longitudinally predominantly using centromeric or telomeric probes and to a lesser extent with whole chromosome paints. To date, studies investigating the radial organisation of human sperm have been limited. The purpose of this study was to utilise whole chromosome paints for six clinically important chromosomes (18, 19, 21, 22, X, and Y) to investigate nuclear address by assessing their radial and longitudinal nuclear organisation. A total of 10,800 sperm were analysed in nine normozoospermic individuals. The results have shown nonrandom chromosome position for all chromosomes using both methods of analysis. We present novel radial and polar analysis of chromosome territory localization within the human sperm nucleus. Specifically, a hierarchical organisation was observed radially with chromosomes organised from the interior to the periphery (chromosomes 22, 21, Y, X, 19, and 18 respectively) and polar organisation from the sperm head to tail (chromosomes X, 19, Y, 22, 21, and 18, respectively). We provide evidence of defined nuclear organisation in the human sperm and discuss the function of organisation and potential possible clinical ramifications of these results in regards to male infertility and early human development.


Assuntos
Cromossomos Humanos/genética , Espermatozoides/citologia , Adulto , Núcleo Celular/genética , Polaridade Celular , Centrômero/genética , Coloração Cromossômica , Cromossomos Humanos/metabolismo , Desenvolvimento Embrionário , Genoma Humano , Humanos , Hibridização in Situ Fluorescente/métodos , Infertilidade Masculina/genética , Masculino , Pessoa de Meia-Idade , Cabeça do Espermatozoide , Espermatogênese/genética , Telômero
8.
HIV Med ; 12(7): 442-6, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21395964

RESUMO

BACKGROUND: We evaluated the efficacy, safety and tolerability of etravirine in paediatric patients vertically infected with HIV-1. METHODS: A multicentre retrospective study of 23 multidrug-resistant paediatric patients (five children and 18 adolescents) enrolled in the study from 1 September 2007 to 28 February 2010 was carried out. We performed a longitudinal analysis of immunological, virological and clinical data. RESULTS: The median age of the patients was 14.2 years [interquartile range (IQR) 12.5-15.8 years]. At baseline, the median HIV-1 RNA was 29 000 (4.5 log(10) ) HIV-1 RNA copies/mL (range 4300-83 000 copies/mL), the median CD4 T-cell count was 445 cells/µL (range 221-655 cells/µL) and the median CD4 percentage was 19.6% (IQR 13.0-31.0). Remarkably, 16 of 23 patients (70%) harboured one or more etravirine-associated resistance mutations. The backbone regimen included at least two fully active drugs in 91% of patients. After etravirine-based therapy, 20 patients (87%) achieved HIV-1 RNA<400 copies/mL and 18 of 23 (78%) achieved HIV-1 RNA<50 copies/mL: three (13%) within the first month, seven (30%) within the first 4 months, and six (26%) between the 5th and 8th months. CD4 T-cell recovery was observed in 19 patients (83%). The median follow-up time was 48.4 weeks (IQR 35.7-63.4 weeks); four patients (17%) were exposed to etravirine for >120 weeks. Three mild/short-term and two moderate skin rashes were observed in the adolescents. Laboratory abnormalities included hypercholesterolaemia (11 of 23 patients), hypertriglyceridaemia (eight of 23 patients), and reduced high-density lipoprotein cholesterol (10 of 23 patients). Adherence was complete in seven patients (30%). No patients showed complete resistance to etravirine after follow-up. However, three of 21 patients (14%) who initially showed intermediate resistance interrupted etravirine treatment because of virological failure. CONCLUSIONS: We observed a sustained antiviral response and improved immunological parameters in multidrug-resistant paediatric patients, most of whom had received etravirine as part of salvage regimens with at least two fully active drugs.


Assuntos
Infecções por HIV/tratamento farmacológico , HIV-1/efeitos dos fármacos , Piridazinas/uso terapêutico , Adolescente , Terapia Antirretroviral de Alta Atividade , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Farmacorresistência Viral , Feminino , Infecções por HIV/epidemiologia , Humanos , Masculino , Nitrilas , Pirimidinas , Estudos Retrospectivos , Espanha/epidemiologia , Resultado do Tratamento
9.
Cell Mol Neurobiol ; 30(8): 1327-33, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21088884

RESUMO

GTPases of the Rho family are molecular switches that play an important role in a wide range of membrane-trafficking processes including neurotransmission and hormone release. We have previously demonstrated that RhoA and Cdc42 regulate calcium-dependent exocytosis in chromaffin cells by controlling actin dynamics, whereas Rac1 regulates lipid organisation. These findings raised the question of the upstream mechanism activating these GTPases during exocytosis. The guanine nucleotide exchange factors (GEFs) that catalyse the exchange of GDP for GTP are crucial elements regulating Rho signalling. Using an RNA interference approach, we have recently demonstrated that the GEFs Intersectin-1L and ß-Pix, play essential roles in neuroendocrine exocytosis by controlling the activity of Cdc42 and Rac1, respectively. This review summarizes these results and discusses the functional importance of Rho GEFs in the exocytotic machinery in neuroendocrine cells.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Cálcio/metabolismo , Exocitose , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Células Neuroendócrinas/metabolismo , Animais , Células PC12 , Ratos , Fatores de Troca de Nucleotídeo Guanina Rho
10.
HIV Med ; 11(4): 245-52, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20050937

RESUMO

OBJECTIVES: Highly active antiretroviral therapy (HAART) has dramatically changed the natural history of HIV infection in children, but there are few studies in the literature about the incidence of clinical manifestations after HAART in this population, compared with adults. The aim of this study was to describe the influence of the widespread use of HAART on the development of opportunistic infections and organ-specific diseases in HIV-infected children. METHODS: An observational study of a cohort of 366 vertically HIV-infected children followed from 1990 to 2006 was carried out. According to the main antiretroviral protocol used, three calendar periods (CPs) were defined and compared: CP1 (1990-1996: no patients on HAART), CP2 (1997-1999: <60% on HAART) and CP3 (2000-2006: >60% on HAART). RESULTS: Children experienced a progressive increase in CD4 T cell count (P<0.05) and a decrease in HIV viral load from 1996 onwards (P<0.05). Similarly, rates of death, AIDS, opportunistic infections (bacteraemia, candidosis, cryptosporidiosis and bacterial pneumonia) and organ-specific diseases (wasting syndrome, thrombocytopenia, cardiomyopathy, lymphoid interstitial pneumonia and HIV-associated encephalopathy) were lower in CP2 and CP3 than in CP1. CONCLUSIONS: This study provides evidence of improved clinical outcomes in HIV-infected children over time and shows that mortality, AIDS, opportunistic infections and organ-specific diseases declined as HAART was progressively instituted in this population.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/epidemiologia , Terapia Antirretroviral de Alta Atividade , Infecções por HIV/tratamento farmacológico , HIV-1 , Adulto , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Infecções por HIV/mortalidade , Humanos , Lactente , Recém-Nascido , Masculino , Espanha/epidemiologia , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Carga Viral
11.
Fertil Steril ; 93(2): 337-8, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20105463

RESUMO

The Suleman case has served as a catalyst to examine a range of clinical and ethical decisions, making the birth of the octuplets a truly transformative event.


Assuntos
Fertilização in vitro/ética , Prole de Múltiplos Nascimentos/estatística & dados numéricos , Gravidez Múltipla , Adulto , California , Ética Médica , Feminino , Humanos , Gravidez , Pessoa Solteira
12.
Rev Neurol (Paris) ; 164(12): 1028-34, 2008 Dec.
Artigo em Francês | MEDLINE | ID: mdl-18808781

RESUMO

INTRODUCTION: In an observational multicenter study, we analyzed retrospectively 30 patients with malignant form of multiple sclerosis (MS) treated with mitoxantrone the year following the first neurological event. METHODS: The 30 patients were selected according to Weinshenker criteria of malignant MS (either a "catastrophic" relapse or a quickly aggressive form). We compared clinical and MRI findings the year before with the year following mitoxantrone onset treatment: annualized relapse rates (ARR), EDSS score and percentage of patients with gadolinium enhancing lesions on MRI. RESULTS: A total of 87 relapses were observed in the 5.7 months before and 10 during the year following onset of mitoxantrone treatment. The ARR decreased by 95% (6.0+/-2 before and 0.3+/-0.7 after). Twenty-four patients (80%) were relapse-free one year after onset of mitoxantrone treatment. The EDSS score improved in 87% of MS patients and the mean EDSS decreased by 1.9. Ninety-seven percent had at least gadolinium enhancing lesions before the start of mitoxantrone treatment as compared to 17% after. CONCLUSION: In our experience, mitoxantrone had a rapid and strong impact on the malignant forms of MS with a short disease duration. In this MS subgroup, mitoxantrone should be considered as an early treatment option.


Assuntos
Imunossupressores/uso terapêutico , Mitoxantrona/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Adulto , Progressão da Doença , Feminino , Gadolínio , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/patologia , Estudos Retrospectivos , Prevenção Secundária , Resultado do Tratamento , Adulto Jovem
13.
J Immunol ; 167(12): 6780-5, 2001 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-11739493

RESUMO

Efficient T cell activation requires at least two signals, one mediated by the engagement of the TCR-CD3 complex and another one mediated by a costimulatory molecule. We recently showed that CD46, a complement regulatory receptor for C3b as well as a receptor for several pathogens, could act as a potent costimulatory molecule for human T cells, highly promoting T cell proliferation. Indeed, we show in this study that CD46/CD3 costimulation induces a synergistic activation of extracellular signal-related kinase mitogen-activated protein kinase. Furthermore, whereas T lymphocytes primarily circulate within the bloodstream, activation may induce their migration toward secondary lymphoid organs or other tissues to encounter APCs or target cells. In this study, we show that CD46/CD3 costimulation also induces drastic morphological changes of primary human T cells, as well as actin relocalization. Moreover, we show that the GTP/GDP exchange factor Vav is phosphorylated upon CD46 stimulation alone, and that CD46/CD3 costimulation induces a synergistic increase of Vav phosphorylation. These results prompted us to investigate whether CD46/CD3 costimulation induced the activation of GTPases from the Rho family. Indeed, we report that the small GTPase Rac is also activated upon CD46/CD3 costimulation, whereas no change of Rho and Cdc42 activity could be detected. Therefore, CD46 costimulation profoundly affects T cell behavior, and these results provide important data concerning the biology of primary human T cells.


Assuntos
Antígenos CD/metabolismo , Complexo CD3/metabolismo , Proteínas de Ciclo Celular , Ativação Linfocitária , Sistema de Sinalização das MAP Quinases , Glicoproteínas de Membrana/metabolismo , Linfócitos T/citologia , Linfócitos T/imunologia , Actinas/análise , Células Cultivadas , Citoesqueleto/ultraestrutura , Ativação Enzimática , Humanos , Cinética , Proteína Cofatora de Membrana , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-vav , Linfócitos T/ultraestrutura , Proteínas rac de Ligação ao GTP/metabolismo
14.
Mol Cell ; 8(5): 983-93, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11741534

RESUMO

Kinase suppressor of Ras (KSR) is a conserved component of the Ras pathway that interacts directly with MEK and MAPK. Here we show that KSR1 translocates from the cytoplasm to the cell surface in response to growth factor treatment and that this process is regulated by Cdc25C-associated kinase 1 (C-TAK1). C-TAK1 constitutively associates with mammalian KSR1 and phosphorylates serine 392 to confer 14-3-3 binding and cytoplasmic sequestration of KSR1 in unstimulated cells. In response to signal activation, the phosphorylation state of S392 is reduced, allowing the KSR1 complex to colocalize with activated Ras and Raf-1 at the plasma membrane, thereby facilitating the phosphorylation reactions required for the activation of MEK and MAPK.


Assuntos
MAP Quinase Quinase Quinase 1 , Proteínas Quinases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transporte Proteico/fisiologia , Transdução de Sinais/fisiologia , Proteínas ras/metabolismo , Animais , Células COS , Microscopia de Fluorescência , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Modelos Biológicos , Fosforilação , Proteínas Quinases/genética , Proteínas Proto-Oncogênicas c-raf/metabolismo
15.
J Soc Gynecol Investig ; 8(3): 174-8, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11390253

RESUMO

OBJECTIVE: Originating from the pituitary gland, TSH secretion is regulated predominantly by thyroid-releasing hormone (TRH) neurons located in the hypothalamus. Norepinephrine and dopamine have important effects in modulation of TSH secretion. An inhibitor of catecholamine synthesis, alpha-methyl-para-tyrosine (AMPT) has been used in several studies of the regulation of human TSH secretion. The short-term effects (<8 hours) of low doses of AMPT include stimulation of pituitary TSH secretion by selective lowering of brain dopamine levels. After prolonged administration of AMPT (>24 hours), theoretically both dopamine and norepinephrine levels are lowered significantly in the brain, although this has not been reported previously. METHODS: Nine subjects (five women and four men) received a total of five 1-g doses of AMPT or five 50-mg doses of promethazine (active placebo) over 28 hours in a randomized, double-blind, placebo-controlled crossover design in which the active and control tests were separated by 4-6 weeks. Blood samples were obtained over 24 hours (18 time points) on day 2 of each condition. RESULTS: Changes in prolactin secretion and 6-hydroxymelatonin sulfate excretion indirectly showed the effects of AMPT on dopamine and norepinephrine. The typical circadian rhythm of TSH secretion was blunted by AMPT throughout the night; at ten time points, the difference between the two groups was statistically significant (P <.01). The long-term effects of repeated doses of AMPT were inhibition of TSH secretion and significant attenuation of the circadian rhythm of TSH. Additionally, AMPT induced low norepinephrine levels, which counteracted the stimulatory effect of low dopamine levels on TSH. CONCLUSION: Through its inhibitory effect on TRH, norepinephrine appeared to be involved in the regulation of TSH.


Assuntos
Catecolaminas/antagonistas & inibidores , Ritmo Circadiano , Melatonina/análogos & derivados , Sinapses , Tireotropina/metabolismo , alfa-Metiltirosina/farmacologia , Adulto , Catecolaminas/biossíntese , Estudos Cross-Over , Dopamina/fisiologia , Método Duplo-Cego , Inibidores Enzimáticos/farmacologia , Epinefrina/fisiologia , Feminino , Humanos , Masculino , Melatonina/metabolismo , Placebos , Prolactina/metabolismo , Prometazina/administração & dosagem , Tirosina 3-Mono-Oxigenase/antagonistas & inibidores , alfa-Metiltirosina/administração & dosagem
17.
J Cell Sci ; 113 ( Pt 7): 1177-88, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10704369

RESUMO

Multinucleated giant cells (MNGC) derived from avian blood monocytes present, like osteoclasts, an unusual cytoskeletal organization characterized by (1) cortical rings of actin filaments, (2) unique adhesion structures called podosomes and (3) vinculin containing focal complexes which are not visibly connected to F-actin structures. The Rho family of small GTPases plays an essential role in the regulation and organization of cellular cytoskeletal structures including F-actin and vinculin associated structures. Using bacterial toxins such as modified exoenzyme C3 (C3B) and toxin B or overexpression of constitutively active Rac and Rho proteins fused to the green fluorescent protein (GFP), we show that Rac and Rho play antagonistic roles in regulating the morphology of osteoclast-like cells. Inhibition of Rho by C3B triggered MNGC spreading whereas activated Rho promoted cell retraction. However, inhibition or activation of Rho led to complete disorganization of fibrillar actin structures, including podosomes. Toxin B inhibition of Rho, Rac and Cdc42 induced a time dependent F-actin and vinculin reorganization. Initially, actin fibers with associated adhesion plaques formed and disappeared subsequently. Finally, only small focal complexes remained at the MNGC periphery before retracting. At the time when actin fibers formed, we observed that Rac was already inhibited by toxin B. By combining C3B treatment and overexpression of a dominant negative form of Rac (N17Rac), we show that the formation of these focal adhesion and actin fiber structures required neither Rho nor Rac activity. Moreover, our results show that podosomes are extremely unstable structures since any modifications of Rho or Rac activity resulted in their dissociation.


Assuntos
Actinas/fisiologia , Proteínas de Bactérias , Toxinas Botulínicas , Movimento Celular/fisiologia , Células Gigantes/fisiologia , Proteínas rac de Ligação ao GTP/antagonistas & inibidores , Proteínas rac de Ligação ao GTP/fisiologia , Proteínas rho de Ligação ao GTP/antagonistas & inibidores , Proteínas rho de Ligação ao GTP/fisiologia , Células 3T3 , ADP Ribose Transferases/toxicidade , Actinas/metabolismo , Animais , Toxinas Bacterianas/toxicidade , Adesão Celular/fisiologia , Membrana Celular/metabolismo , Galinhas , Clostridioides difficile/fisiologia , Vetores Genéticos/biossíntese , Células Gigantes/efeitos dos fármacos , Macrófagos/fisiologia , Camundongos , Microfibrilas/metabolismo , Fatores de Tempo , Vinculina/metabolismo , Proteínas rac de Ligação ao GTP/biossíntese , Proteínas rac de Ligação ao GTP/genética , Proteínas rho de Ligação ao GTP/genética , Proteína rhoA de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/fisiologia
18.
Fertil Steril ; 72(6): 1045-8, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10593379

RESUMO

OBJECTIVE: To study the effect of freezing on early stage embryos derived from intracytoplasmic sperm injection (ICSI) or from IVF. DESIGN: Prospective, controlled clinical study. SETTING: Private IVF center. PATIENT(S): Sixty-seven consecutive patients undergoing frozen-thawed embryo transfer cycles. INTERVENTION(S): Early stage embryos were frozen, thawed, and transferred. MAIN OUTCOME MEASURE(S): Post-thaw survival, implantation and pregnancy rates. RESULT(S): We noted an 88% post-thaw survival rate, an 18% implantation rate, and a 52% pregnancy rate in the ICSI group and 81%, 11%, and 25%, respectively, with conventional fertilization. CONCLUSION(S): Early stage embryos (either zygote or 2-4 cells) derived from ICSI can be frozen with confidence and higher post-thaw survival and pregnancy rates can be achieved when compared with those from conventional IVF.


Assuntos
Criopreservação , Transferência Embrionária , Fertilização in vitro , Injeções de Esperma Intracitoplásmicas , Adulto , Implantação do Embrião , Feminino , Temperatura Alta , Humanos , Idade Materna , Gravidez , Taxa de Gravidez , Gravidez de Alto Risco
19.
Fertil Steril ; 72(4): 666-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10521107

RESUMO

OBJECTIVE: To study the effect of in vitro culture on the quality of human testicular sperm and the efficiency of intracytoplasmic sperm injection with in vitro cultured testicular sperm. DESIGN: Clinical study. SETTING: A private IVF center. PATIENT(S): Twenty consecutively seen IVF patients undergoing testicular biopsies for ICSI. INTERVENTION(S): The testicular specimens were cultured in vitro for 24 hours and the isolated spermatozoa were microinjected. MAIN OUTCOME MEASURE(S): Preincubation and postculture sperm motility, and fertilization, implantation, and pregnancy rates after intracytoplasmic sperm injection. RESULT(S): Motility increased from initial nonmotile or twitching sperm to free motile sperm in 18 of 20 cases. The injection of in vitro cultured testicular sperm resulted in a fertilization rate of 58%, an implantation rate of 20%, and a pregnancy rate of 45%. CONCLUSION(S): A testicular biopsy procedure can be performed the day before egg retrieval. Despite the low initial sperm quality, a high percentage of the prepared testicular sperm showed increased motility after 24 hours of culture. The injection of in vitro cultured testicular sperm into matured oocytes resulted in fertilization, implantation, and pregnancy rates comparable to those obtained with ejaculated sperm.


Assuntos
Oócitos , Injeções de Esperma Intracitoplásmicas , Espermatozoides , Coleta de Tecidos e Órgãos , Adulto , Células Cultivadas , Implantação do Embrião , Feminino , Fertilização , Humanos , Masculino , Gravidez , Taxa de Gravidez , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Testículo , Fatores de Tempo
20.
Eur Neuropsychopharmacol ; 9(1-2): 61-6, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10082229

RESUMO

Because it is a competitive inhibitor of tyrosine hydroxylase, alpha-methyl-para-tyrosine (AMPT) is used to study psychiatric disorders. Melatonin serves as a biological marker of catecholamine function since its secretion is regulated by noradrenergic neurons via beta-adrenergic receptors in the pineal gland. Ten healthy volunteers were administered AMPT in a double-blind placebo controlled study. When subjects received AMPT, nocturnal 6-hydroxymelatonin sulfate (6-SM) decreased significantly as compared with promethazine (night 1 P=0.002; and night 2 P=0.001). Urinary MHPG also decreased on both study days (DF1,9 F=9.82, GG=0.0121). Nocturnal 6-SM excretion and melatonin secretion correlated highly (r=0.91, P=0.0007). Behavioral ratings did not reveal a difference in symptomatology and did not correlate with changes in 6-SM or MHPG. This study demonstrates in healthy controls that 6-SM reliably reflects presynaptic catecholamine depletion induced by AMPT without the emergence of behavioral symptoms.


Assuntos
Catecolaminas/metabolismo , Inibidores Enzimáticos/farmacologia , Melatonina/análogos & derivados , Receptores Pré-Sinápticos/metabolismo , Tirosina 3-Mono-Oxigenase/antagonistas & inibidores , alfa-Metiltirosina/farmacologia , Adulto , Área Sob a Curva , Estudos Cross-Over , Método Duplo-Cego , Inibidores Enzimáticos/efeitos adversos , Feminino , Humanos , Masculino , Melatonina/sangue , Melatonina/metabolismo , Melatonina/urina , Norepinefrina/metabolismo , alfa-Metiltirosina/efeitos adversos
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