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1.
J Transl Med ; 18(1): 14, 2020 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-31918710

RESUMEN

BACKGROUND: Artificial intelligence (AI), with its seemingly limitless power, holds the promise to truly revolutionize patient healthcare. However, the discourse carried out in public does not always correlate with the actual impact. Thus, we aimed to obtain both an overview of how French health professionals perceive the arrival of AI in daily practice and the perception of the other actors involved in AI to have an overall understanding of this issue. METHODS: Forty French stakeholders with diverse backgrounds were interviewed in Paris between October 2017 and June 2018 and their contributions analyzed using the grounded theory method (GTM). RESULTS: The interviews showed that the various actors involved all see AI as a myth to be debunked. However, their views differed. French healthcare professionals, who are strategically placed in the adoption of AI tools, were focused on providing the best and safest care for their patients. Contrary to popular belief, they are not always seeing the use of these tools in their practice. For healthcare industrial partners, AI is a true breakthrough but legal difficulties to access individual health data could hamper its development. Institutional players are aware that they will have to play a significant role concerning the regulation of the use of these tools. From an external point of view, individuals without a conflict of interest have significant concerns about the sustainability of the balance between health, social justice, and freedom. Health researchers specialized in AI have a more pragmatic point of view and hope for a better transition from research to practice. CONCLUSION: Although some hyperbole has taken over the discourse on AI in healthcare, diverse opinions and points of view have emerged among French stakeholders. The development of AI tools in healthcare will be satisfactory for everyone only by initiating a collaborative effort between all those involved. It is thus time to also consider the opinion of patients and, together, address the remaining questions, such as that of responsibility.


Asunto(s)
Inteligencia Artificial , Atención a la Salud , Francia , Humanos , Opinión Pública , Encuestas y Cuestionarios
2.
Acta Psychiatr Scand ; 138(5): 379-400, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29904907

RESUMEN

OBJECTIVE: Evidence-based guidance of clinical decision-making for the management of Autism Spectrum Disorder (ASD) is lacking, particularly for co-occurring psychiatric symptoms. This review evaluates treatment evidence for six common symptom targets in children/adolescents with ASD and provides a resource to facilitate application of the evidence to clinical practice. METHOD: A systematic search identified randomized controlled trials (RCTs) and high-quality systematic reviews published between 2007 and 2016, focused on: social interaction/communication impairment, stereotypic/repetitive behaviours, irritability/agitation, attention-deficit/hyperactivity disorder symptoms, mood or anxiety symptoms, and sleep difficulties. We then completed qualitative evaluation of high-quality systematic reviews/meta-analyses and quantitative evaluation of recently published RCTs not covered by prior comprehensive systematic reviews. RESULTS: Recently published RCTs focused on social interaction and communication impairment (trials = 32) using psychosocial interventions. Interventions for irritability/agitation (trials = 16) were mainly pharmacological. Few RCTs focused on other symptom targets (trials = 2-5/target). Integration of these results with our qualitative review indicated that few established treatment modalities exist, and available evidence is limited by small studies with high risk of bias. CONCLUSION: Given the current evidence-base, treatment targets must be clearly defined, and a systematic approach to intervention trials in children/adolescents with ASD must be undertaken with careful consideration of the limitations of safety/efficacy data.


Asunto(s)
Trastornos de Ansiedad/terapia , Trastorno por Déficit de Atención con Hiperactividad/terapia , Trastorno del Espectro Autista/terapia , Trastornos de la Comunicación/terapia , Trastornos del Humor/terapia , Guías de Práctica Clínica como Asunto , Agitación Psicomotora/terapia , Trastornos del Sueño-Vigilia/terapia , Conducta Estereotipada , Adolescente , Trastornos de Ansiedad/etiología , Trastorno por Déficit de Atención con Hiperactividad/etiología , Trastorno del Espectro Autista/complicaciones , Niño , Trastornos de la Comunicación/etiología , Humanos , Trastornos del Humor/etiología , Agitación Psicomotora/etiología , Trastornos del Sueño-Vigilia/etiología
3.
Psychol Med ; 47(4): 639-654, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27825394

RESUMEN

BACKGROUND: Autism spectrum disorder (ASD) is a highly heritable neurodevelopmental disorder, yet the search for definite genetic etiologies remains elusive. Delineating ASD endophenotypes can boost the statistical power to identify the genetic etiologies and pathophysiology of ASD. We aimed to test for endophenotypes of neuroanatomy and associated intrinsic functional connectivity (iFC) via contrasting male youth with ASD, their unaffected brothers and typically developing (TD) males. METHOD: The 94 participants (aged 9-19 years) - 20 male youth with ASD, 20 unaffected brothers and 54 TD males - received clinical assessments, and undertook structural and resting-state functional magnetic resonance imaging scans. Voxel-based morphometry was performed to obtain regional gray and white matter volumes. A seed-based approach, with seeds defined by the regions demonstrating atypical neuroanatomy shared by youth with ASD and unaffected brothers, was implemented to derive iFC. General linear models were used to compare brain structures and iFC among the three groups. Assessment of familiality was investigated by permutation tests for variance of the within-family pair difference. RESULTS: We found that atypical gray matter volume in the mid-cingulate cortex was shared between male youth with ASD and their unaffected brothers as compared with TD males. Moreover, reduced iFC between the mid-cingulate cortex and the right inferior frontal gyrus, and increased iFC between the mid-cingulate cortex and bilateral middle occipital gyrus were the shared features of male ASD youth and unaffected brothers. CONCLUSIONS: Atypical neuroanatomy and iFC surrounding the mid-cingulate cortex may be a potential endophenotypic marker for ASD in males.


Asunto(s)
Trastorno del Espectro Autista , Corteza Cerebral/fisiopatología , Conectoma/métodos , Endofenotipos , Sustancia Gris/patología , Hermanos , Sustancia Blanca/patología , Adolescente , Adulto , Trastorno del Espectro Autista/diagnóstico por imagen , Trastorno del Espectro Autista/patología , Trastorno del Espectro Autista/fisiopatología , Corteza Cerebral/diagnóstico por imagen , Niño , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Sustancia Blanca/diagnóstico por imagen , Adulto Joven
4.
Cereb Cortex ; 26(7): 3297-309, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27130663

RESUMEN

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition, which is accompanied by differences in gray matter neuroanatomy and white matter connectivity. However, it is unknown whether these differences are linked or reflect independent aetiologies. Using a multimodal neuroimaging approach, we therefore examined 51 male adults with ASD and 48 neurotypical controls to investigate the relationship between gray matter local gyrification (lGI) and white matter diffusivity in associated fiber tracts. First, ASD individuals had a significant increase in gyrification around the left pre- and post-central gyrus. Second, white matter fiber tracts originating and/or terminating in the cluster of increased lGI had a significant increase in axial diffusivity. This increase in diffusivity was predominantly observed in tracts in close proximity to the cortical sheet. Last, we demonstrate that the increase in lGI was significantly correlated with increased diffusivity of short tracts. This relationship was not significantly modulated by a main effect of group (i.e., ASD), which was more closely associated with gray matter gyrification than white matter diffusivity. Our findings suggest that differences in gray matter neuroanatomy and white matter connectivity are closely linked, and may reflect common rather than distinct aetiological pathways.


Asunto(s)
Trastorno del Espectro Autista/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Sustancia Gris/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Adolescente , Adulto , Imagen de Difusión Tensora , Humanos , Imagenología Tridimensional , Inteligencia , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/diagnóstico por imagen , Tamaño de los Órganos , Reconocimiento de Normas Patrones Automatizadas , Adulto Joven
5.
Psychol Med ; 46(12): 2561-9, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27345441

RESUMEN

BACKGROUND: Little is known about time perception, its putative role as cognitive endophenotype, and its neuroanatomical underpinnings in adults with attention deficit hyperactivity disorder (ADHD). METHOD: Twenty adults with ADHD, 20 unaffected first-degree relatives and 20 typically developing controls matched for age and gender undertook structural magnetic resonance imaging scans. Voxel-based morphometry with DARTEL was performed to obtain regional grey-matter volumes. Temporal processing was investigated as a putative cognitive endophenotype using a temporal reproduction paradigm. General linear modelling was employed to examine the relationship between temporal reproduction performances and grey-matter volumes. RESULTS: ADHD participants were impaired in temporal reproduction and unaffected first-degree relatives performed in between their ADHD probands and typically developing controls. Increased grey-matter volume in the cerebellum was associated with poorer temporal reproduction performance. CONCLUSIONS: Adults with ADHD are impaired in time reproduction. Performances of the unaffected first-degree relatives are in between ADHD relatives and controls, suggesting that time reproduction might be a cognitive endophenotype for adult ADHD. The cerebellum is involved in time reproduction and might play a role in driving time performances.


Asunto(s)
Trastorno por Déficit de Atención con Hiperactividad/patología , Trastorno por Déficit de Atención con Hiperactividad/fisiopatología , Sustancia Gris/patología , Percepción del Tiempo/fisiología , Adulto , Trastorno por Déficit de Atención con Hiperactividad/diagnóstico por imagen , Endofenotipos , Femenino , Sustancia Gris/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Núcleo Familiar , Adulto Joven
6.
Psychol Med ; 44(15): 3215-27, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25065819

RESUMEN

BACKGROUND: Mentalizing deficits are a hallmark of the autism spectrum condition (ASC) and a potential endophenotype for atypical social cognition in ASC. Differences in performance and neural activation on the 'Reading the Mind in the Eyes' task (the Eyes task) have been identified in individuals with ASC in previous studies. METHOD: Performance on the Eyes task along with the associated neural activation was examined in adolescents with ASC (n = 50), their unaffected siblings (n = 40) and typically developing controls (n = 40). Based on prior literature that males and females with ASC display different cognitive and associated neural characteristics, analyses were stratified by sex. Three strategies were applied to test for endophenotypes at the level of neural activation: (1) identifying and locating conjunctions of ASC-control and sibling-control differences; (2) examining whether the sibling group is comparable to the ASC or intermediate between the ASC and control groups; and (3) examining spatial overlaps between ASC-control and sibling-control differences across multiple thresholds. RESULTS: Impaired behavioural performance on the Eyes task was observed in males with ASC compared to controls, but only at trend level in females; and no difference in performance was identified between sibling and same-sex control groups in both sexes. Neural activation showed a substantial endophenotype effect in the female groups but this was only modest in the male groups. CONCLUSIONS: Behavioural impairment on complex emotion recognition associated with mental state attribution is a phenotypic, rather than an endophenotypic, marker of ASC. However, the neural response during the Eyes task is a potential endophenotypic marker for ASC, particularly in females.


Asunto(s)
Encéfalo/fisiopatología , Trastornos Generalizados del Desarrollo Infantil/fisiopatología , Expresión Facial , Hermanos , Teoría de la Mente/fisiología , Adolescente , Endofenotipos , Ojo , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Factores Sexuales
7.
Malays Orthop J ; 16(1): 130-133, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35519533

RESUMEN

Poliomyelitis is on the verge of eradication since the introduction of the vaccine in 1950. In developed countries, those afflicted with the disease are primarily in their sixth decade and beyond, usually with disabling complications. Due to the diminished muscle power coupled with the abnormal bony anatomy and joint contractures, patients with polio present unique surgical challenges when they sustain fragility fractures. We report an uncommon case of intertrochanteric hip fracture in a limb affected with polio and hip dysplasia, on a background of ipsilateral distal femur fracture with previous surgical fixation. We aim to outline the challenges encountered during the surgery and the preoperative planning to overcome these shortcomings.

8.
Ann Burns Fire Disasters ; 34(3): 264-276, 2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34744543

RESUMEN

Since 2016 there has been a 20-fold increase in known burns injury from personal mobility device (PMD) related fires. The root cause is the failure of high-density lithium ion (Li-ion) battery packs powering the PMDs. This failure process, known as thermal runaway, is well documented in applied science journals. Importantly, the liberation of hydrogen fluoride from failing Li-ion batteries may contribute to unrecognized chemical burns. A clinical gap in knowledge exists in the understanding of the explosive nature of Li-ion batteries. We reviewed the electrochemical pathophysiology of a failing Li-ion cell as it impacts clinical management of burn injuries. This retrospective study was carried out in two major institutions in Singapore. All admitted PMD-related burns and follow up appointments were captured and reviewed from 2016 - 2020. Thirty patients were admitted to tertiary hospitals, 43% of patients were in the pediatric population and 57% were adult patients, aged from 0.3 to 77 years. TBSA of burns ranged from 0 to 80% with a mean 14.5%. 73% of cases presented with inhalation injury, 8 of whom did not suffer any cutaneous burns. 50% of patients sustained both cutaneous and inhalation burn injuries. 27% of patients sustained major burns of >20% TBSA, with 2 in the pediatric group. Mortali ty rate was 10% from PMD-related fires. This cause of burn injury has proven to be fa tal. Prevention of PMD-related fires by ensuring proper battery utilization, adherence to PMD sanctions for battery standards and public education is vital to reducing the morbidity and mortality of this unique type of thermal injury.


Depuis 2016, les rapports de brûlures après incendie de véhicules électriques personnels (VEP) ont été multipliés par 20. La cause essentielle en est le dysfonctionnement de la batterie lithium/ion (Li/ion) les motorisant. Ce dysfonctionnement est connu sous le terme d'emballement thermique, bien décrit dans les revues technologiques. La libération de fluorure d'hydrogène lors de cette réaction peut entraîner des brûlures chimiques ignorées et la physiopathologie exacte de ces brûlures reste largement méconnue des cliniciens. Nous avons revu les mécanismes physico- chimiques de l'emballement thermique des batteries Li/ion et leur conséquences sur la prise en charge des brûlures occasionnées. Cette étude rétrospective a été réalisée par 2 grosses structures singapouriennes. Tous les dossiers d'accidents de VEP survenus entre 2016 et 2020, comprenant le suivi à distance, ont été revus. Ils regroupaient 30 patients âgés de 3 mois à 77 ans, dont 43% d'enfants. La surface brûlée représentait 0 à 80% de SCT (moyenne 14,5%) et 27% des patients (dont 2 enfants) étaient brûlés sur plus de 20% SCT. Une inhalation était retrouvée dans 73% des cas (dont 8 sans brûlure cutanée). La moitié des patients avaient une brûlure et une inhalation. La mortalité s'élevait à 10%. La prévention de ces accidents par le contrôle- qualité des batteries (sanctions à l'appui) et l'éducation à l'utilisation correcte des VEP et de leur batterie est nécessaire pour éviter ces dysfonctionnements potentiellement létaux.

9.
Transl Psychiatry ; 7(4): e1099, 2017 04 18.
Artículo en Inglés | MEDLINE | ID: mdl-28418398

RESUMEN

Oxytocin may influence various human behaviors and the connectivity across subcortical and cortical networks. Previous oxytocin studies are male biased and often constrained by task-based inferences. Here, we investigate the impact of oxytocin on resting-state connectivity between subcortical and cortical networks in women. We collected resting-state functional magnetic resonance imaging (fMRI) data on 26 typically developing women 40 min following intranasal oxytocin administration using a double-blind placebo-controlled crossover design. Independent components analysis (ICA) was applied to examine connectivity between networks. An independent analysis of oxytocin receptor (OXTR) gene expression in human subcortical and cortical areas was carried out to determine plausibility of direct oxytocin effects on OXTR. In women, OXTR was highly expressed in striatal and other subcortical regions, but showed modest expression in cortical areas. Oxytocin increased connectivity between corticostriatal circuitry typically involved in reward, emotion, social communication, language and pain processing. This effect was 1.39 standard deviations above the null effect of no difference between oxytocin and placebo. This oxytocin-related effect on corticostriatal connectivity covaried with autistic traits, such that oxytocin-related increase in connectivity was stronger in individuals with higher autistic traits. In sum, oxytocin strengthened corticostriatal connectivity in women, particularly with cortical networks that are involved in social-communicative, motivational and affective processes. This effect may be important for future work on neurological and psychiatric conditions (for example, autism), particularly through highlighting how oxytocin may operate differently for subsets of individuals.


Asunto(s)
Corteza Cerebral/efectos de los fármacos , Conectoma , Cuerpo Estriado/efectos de los fármacos , Red Nerviosa/efectos de los fármacos , Administración Intranasal , Adulto , Afecto/efectos de los fármacos , Corteza Cerebral/diagnóstico por imagen , Comunicación , Cuerpo Estriado/diagnóstico por imagen , Método Doble Ciego , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Motivación/efectos de los fármacos , Red Nerviosa/diagnóstico por imagen , Receptores de Oxitocina/genética , Conducta Social , Adulto Joven
10.
Transl Psychiatry ; 7(4): e1090, 2017 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-28398337

RESUMEN

Autism spectrum conditions (ASC) are more prevalent in males than females. The biological basis of this difference remains unclear. It has been postulated that one of the primary causes of ASC is a partial disconnection of the frontal lobe from higher-order association areas during development (that is, a frontal 'disconnection syndrome'). Therefore, in the current study we investigated whether frontal connectivity differs between males and females with ASC. We recruited 98 adults with a confirmed high-functioning ASC diagnosis (61 males: aged 18-41 years; 37 females: aged 18-37 years) and 115 neurotypical controls (61 males: aged 18-45 years; 54 females: aged 18-52 years). Current ASC symptoms were evaluated using the Autism Diagnostic Observation Schedule (ADOS). Diffusion tensor imaging was performed and fractional anisotropy (FA) maps were created. Mean FA values were determined for five frontal fiber bundles and two non-frontal fiber tracts. Between-group differences in mean tract FA, as well as sex-by-diagnosis interactions were assessed. Additional analyses including ADOS scores informed us on the influence of current ASC symptom severity on frontal connectivity. We found that males with ASC had higher scores of current symptom severity than females, and had significantly lower mean FA values for all but one tract compared to controls. No differences were found between females with or without ASC. Significant sex-by-diagnosis effects were limited to the frontal tracts. Taking current ASC symptom severity scores into account did not alter the findings, although the observed power for these analyses varied. We suggest these findings of frontal connectivity abnormalities in males with ASC, but not in females with ASC, have the potential to inform us on some of the sex differences reported in the behavioral phenotype of ASC.


Asunto(s)
Trastorno del Espectro Autista/diagnóstico por imagen , Trastorno del Espectro Autista/patología , Imagen de Difusión Tensora , Lóbulo Frontal/diagnóstico por imagen , Lóbulo Frontal/patología , Vías Nerviosas/diagnóstico por imagen , Vías Nerviosas/patología , Adolescente , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Adulto Joven
11.
Cancer Res ; 49(17): 4842-5, 1989 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-2547520

RESUMEN

One of the body's natural defense mechanisms against tumor cells is lysis of the invading cell by cytotoxic T-cells and natural killer (NK) cells. Five human hepatocellular carcinoma cell lines were found to have different sensitivities to killing by peripheral blood monocytes in a 51Cr release assay. This killing was demonstrated to be due to NK cell lysis. Electrical recording measurements of the membrane potentials of these five cell lines showed different values for each line, all below values reported for normal hepatocytes. Correlation between mean cell membrane potential, and sensitivity to NK lysis, revealed an inverse relationship. In this study we demonstrate that the lower the mean membrane potential of a human hepatocellular carcinoma cell line, the more sensitive it is to NK cell cytolysis. Cell surface positive potential did not correlate with NK cytolysis and only a weak correlation was found between cell membrane negative potential and cell surface positive potential between cell lines.


Asunto(s)
Carcinoma Hepatocelular/inmunología , Citotoxicidad Inmunológica , Células Asesinas Naturales/inmunología , Neoplasias Hepáticas/inmunología , Carcinoma Hepatocelular/fisiopatología , Citotoxicidad Inmunológica/efectos de los fármacos , Humanos , Interferón Tipo I/farmacología , Neoplasias Hepáticas/fisiopatología , Potenciales de la Membrana/efectos de los fármacos , Cloruro de Potasio/farmacología , Proteínas Recombinantes , Células Tumorales Cultivadas , Valinomicina/farmacología
12.
Phys Rev E ; 93(5): 053114, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27300985

RESUMEN

Most of the existing numerical and theoretical investigations on the electrohydrodynamics of a viscous drop have focused on the creeping Stokes flow regime, where nonlinear inertia effects are neglected. In this work we study the inertia effects on the electrodeformation of a viscous drop under a DC electric field using a novel second-order immersed interface method. The inertia effects are quantified by the Ohnesorge number Oh, and the electric field is characterized by an electric capillary number Ca_{E}. Below the critical Ca_{E}, small to moderate electric field strength gives rise to steady equilibrium drop shapes. We found that, at a fixed Ca_{E}, inertia effects induce larger deformation for an oblate drop than a prolate drop, consistent with previous results in the literature. Moreover, our simulations results indicate that inertia effects on the equilibrium drop deformation are dictated by the direction of normal electric stress on the drop interface: Larger drop deformation is found when the normal electric stress points outward, and smaller drop deformation is found otherwise. To our knowledge, such inertia effects on the equilibrium drop deformation has not been reported in the literature. Above the critical Ca_{E}, no steady equilibrium drop deformation can be found, and often the drop breaks up into a number of daughter droplets. In particular, our Navier-Stokes simulations show that, for the parameters we use, (1) daughter droplets are larger in the presence of inertia, (2) the drop deformation evolves more rapidly compared to creeping flow, and (3) complex distribution of electric stresses for drops with inertia effects. Our results suggest that normal electric pressure may be a useful tool in predicting drop pinch-off in oblate deformations.

13.
Artículo en Inglés | MEDLINE | ID: mdl-26651631

RESUMEN

Many eukaryotic cells undergo frequent shape changes (described as amoeboid motion) that enable them to move forward. We investigate the effect of confinement on a minimal model of amoeboid swimmer. A complex picture emerges: (i) The swimmer's nature (i.e., either pusher or puller) can be modified by confinement, thus suggesting that this is not an intrinsic property of the swimmer. This swimming nature transition stems from intricate internal degrees of freedom of membrane deformation. (ii) The swimming speed might increase with increasing confinement before decreasing again for stronger confinements. (iii) A straight amoeoboid swimmer's trajectory in the channel can become unstable, and ample lateral excursions of the swimmer prevail. This happens for both pusher- and puller-type swimmers. For weak confinement, these excursions are symmetric, while they become asymmetric at stronger confinement, whereby the swimmer is located closer to one of the two walls. In this study, we combine numerical and theoretical analyses.


Asunto(s)
Amoeba/fisiología , Modelos Biológicos , Movimiento , Natación
14.
Transl Psychiatry ; 5: e529, 2015 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-25781228

RESUMEN

During adolescence, white matter microstructure undergoes an important stage of development. It is hypothesized that the alterations of brain connectivity that have a key role in autism spectrum conditions (ASCs) may interact with the development of white matter microstructure. This interaction may be present beyond the phenotype of autism in siblings of individuals with ASC, who are 10 to 20 times more likely to develop certain forms of ASC. We use diffusion tensor imaging to examine how white matter microstructure measurements correlate with age in typically developing individuals, and how this correlation differs in n=43 adolescents with ASC and their n=38 siblings. Correlations observed in n=40 typically developing individuals match developmental changes noted in previous longitudinal studies. In comparison, individuals with ASC display weaker negative correlation between age and mean diffusivity in a broad area centred in the right superior longitudinal fasciculus. These differences may be caused either by increased heterogeneity in ASC or by temporal alterations in the group's developmental pattern. Siblings of individuals with ASC also show diminished negative correlation between age and one component of mean diffusivity-second diffusion eigenvalue-in the right superior longitudinal fasciculus. As the observed differences match for location and correlation directionality in our comparison of typically developing individuals to those with ASC and their siblings, we propose that these alterations constitute a part of the endophenotype of autism.


Asunto(s)
Desarrollo del Adolescente/fisiología , Trastorno Autístico/patología , Fenotipo , Sustancia Blanca/patología , Adolescente , Adulto , Factores de Edad , Niño , Imagen de Difusión Tensora , Endofenotipos , Femenino , Humanos , Masculino , Hermanos , Adulto Joven
15.
Invest Ophthalmol Vis Sci ; 39(11): 2095-104, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9761288

RESUMEN

PURPOSE: To show the production of sense or antisense transcripts by recombinant adenoviruses, to investigate whether the transcripts produced were suitable for downregulating the expression of the targeted gene, cathepsin S (CatS), and to examine the effect of antisense transcript production on the biologic function of retinal pigment epithelial (RPE) cells, including the regulation of endogenous aspartic protease expression. METHODS: Ad.MLP.CatSAS, Ad.RSV.CatSAS, and Ad.MLP.CatSS recombinant viruses were produced by homologous recombination. The recombinant viruses were tested by restriction enzyme digestion to confirm the orientation of the inserts. The expression of antisense transcripts was tested by northern blot analysis. Western blot analysis was used to study the regulation of the endogenous CatS protein in ARPE19 cells. The biologic effect of CatS downregulation in ARPE19 cells was tested by proliferation and phagocytosis assays, de novo cathepsin D (CatD) synthesis, and measurement of aspartic protease activity. RESULTS: After characterization of the recombinant adenovirus constructs, the production of antisense and sense CatS transcripts was shown in ARPE19 cells. The transcripts appeared at approximately 1.9 kb 48 hours after transduction, and the expression of the antisense transcripts was similar in constructs carrying either the MLP or the RSV promoter. Western blot analysis showed that ARPE19 cells transduced with Ad.MLP.CatSAS and Ad.RSV.CatSAS had no detectable CatS. In contrast, there was a strong signal appearing at 24 kDa in ARPE19 cells transduced with Ad.MLP.CatSS. ARPE19 cells were transduced to a high level. The transduction of ARPE19 cells with the recombinant adenoviruses did not affect the morphologic appearance of the cells, their proliferation, or their phagocytosing ability. However, ARPE19 cells transduced by Ad.MLP.CatSAS recombinant adenovirus showed a significant downregulation of de novo CatD synthesis and a twofold decrease in aspartic protease activity. CONCLUSIONS: Recombinant adenoviruses were shown to be suitable for producing antisense CatS transcripts to modulate endogenous CatS expression in RPE cells. It is proposed that CatS may play an important role, directly or indirectly, in the lysosomal digestion of outer segments through the regulation of other lysosomal enzyme activity, such as the expression of CatD.


Asunto(s)
Adenoviridae/genética , Elementos sin Sentido (Genética)/metabolismo , Catepsinas/metabolismo , Epitelio Pigmentado Ocular/enzimología , Elementos sin Sentido (Genética)/genética , Northern Blotting , Western Blotting , Catepsinas/genética , División Celular , Línea Celular , Células Cultivadas , Regulación hacia Abajo , Técnica del Anticuerpo Fluorescente Indirecta , Expresión Génica , Técnicas de Transferencia de Gen , Humanos , Proteínas de la Membrana/metabolismo , Sondas de Oligonucleótidos/química , Fagocitosis/fisiología , Fosfoproteínas/metabolismo , Epitelio Pigmentado Ocular/virología , Plásmidos , ARN Mensajero/metabolismo , Segmento Externo de la Célula en Bastón/metabolismo , Proteína de la Zonula Occludens-1
16.
Antiviral Res ; 24(4): 327-40, 1994 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7527624

RESUMEN

Primary mouse embryo fibroblasts from 4 strains of mice (BALB/c, C57Bl/6, B6.C-H-28c and CBA) were infected with either Newcastle disease virus or murine cytomegalovirus. The time course of the total type I interferon response was assessed and the presence of individual subtypes determined. The total type I interferon produced was titrated using the cytopathic effect reduction assay and the relative levels of type I interferon subtypes expressed (alpha 1, alpha 4, alpha 5, alpha 6 and beta) were evaluated using a reverse transcription-polymerase chain reaction-based technique. In general, the patterns of type I interferon subtypes expressed appeared to be determined by the strain of mouse cells used rather than the inducing virus. However, the overall titre of type I interferons produced in response to a given virus was quite uniform across the strains of mice from which the mouse embryo fibroblasts were derived regardless of the subtype expression pattern. The latter observation fits the proposition that "cross-talk" or feedback between the type I interferon genes and their products is is occurring and that the inducer determines the level of response.


Asunto(s)
Fibroblastos/metabolismo , Fibroblastos/virología , Interferón Tipo I/biosíntesis , Interferón Tipo I/clasificación , Animales , Secuencia de Bases , Embrión de Pollo , Citomegalovirus/crecimiento & desarrollo , Estabilidad de Medicamentos , Embrión de Mamíferos , Femenino , Fibroblastos/fisiología , Genotipo , Concentración de Iones de Hidrógeno , Interferón Tipo I/genética , Interferón beta/biosíntesis , Interferón beta/clasificación , Interferón beta/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos CBA , Datos de Secuencia Molecular , Virus de la Enfermedad de Newcastle/crecimiento & desarrollo , Reacción en Cadena de la Polimerasa , ADN Polimerasa Dirigida por ARN , Activación Viral
17.
Antiviral Res ; 18(1): 65-76, 1992 May.
Artículo en Inglés | MEDLINE | ID: mdl-1329645

RESUMEN

Site-directed in vitro mutagenesis followed by in vitro transcription and translation has been used to study structure/function relationships for murine interferon-alpha 1 (MuIFN-alpha 1). The mature form of the MuIFN-alpha 1 protein was expressed as well as analogue forms with amino acid substitutions at positions 33, 71, 72, 123 and 133. These positions were chosen on the basis of known human interferon-alpha structure/function relationships. Biological assays for antiviral activity on murine cells and natural killer cell activation have been performed for each of the proteins produced. The data obtained have been interpreted in the light of previous human and murine interferon-alpha structure/function work and the recently published three-dimensional structure of murine type I interferon.


Asunto(s)
Virus de la Encefalomiocarditis/fisiología , Interferón-alfa/farmacología , Células Asesinas Naturales/inmunología , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , Interferón-alfa/biosíntesis , Interferón-alfa/química , Interferón-alfa/genética , Activación de Linfocitos , Ratones , Ratones Endogámicos C3H , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Relación Estructura-Actividad
18.
Arch Ophthalmol ; 119(7): 1033-43, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11448325

RESUMEN

OBJECTIVES: To reevaluate the longevity and intraocular safety of recombinant adenovirus (rAd)-mediated gene delivery after subretinal injection, and to prolong transgene expression through the combination of 2 synergistic immunosuppressants. METHODS: An rAd vector carrying green fluorescent protein (GFP) gene was delivered subretinally in the rat eye. The GFP expression was monitored in real time by fundus fluorescent photography. Intraocular safety was examined by observation of changes of retinal pigmentation, cell infiltration in virus-contacted area, immunophenotyping for CD4(+) and CD8(+) cytotoxic T lymphocytes, and CD68(+) macrophages, histologic findings, and dark-adapted electroretinography. Two synergistic immunosuppressants, cyclosporine and sirolimus, were used alone or in combination to prolong transgene expression by temporary immunosuppression. RESULTS: The GFP expression peaked on day 4, dramatically decreased on day 10, and was not detectable on day 14. The decreased GFP expression was coincident with cell infiltration in virus-contacted area. Immunostaining showed that the infiltrating cells were CD4(+) and CD8(+) cytotoxic T lymphocytes and CD68(+) macrophages. Clumped retinal pigmentation and decreased b wave of dark-adapted electroretinogram were observed at 3 to 4 weeks after injection. Histologic examination confirmed rAd-induced retinal degeneration. Transient immunosuppression by cyclosporine and sirolimus, either alone or in combination, improved transgene expression, with the combination being the most efficient. The combined immunosuppression attenuated but did not retard the rAd-induced retinal damage. CONCLUSIONS: Transgene expression mediated by rAd after subretinal delivery is short-term and toxic to the retina. Combination of cyclosporine and sirolimus may act as an immunosuppressive adjunct to prolong rAd-mediated gene transfer. CLINICAL RELEVANCE: The intraocular safety of rAd should be carefully considered before clinical trials are performed.


Asunto(s)
Adenoviridae/genética , Ciclosporina/farmacología , Inmunosupresores/farmacología , Proteínas Luminiscentes/metabolismo , Retina/efectos de los fármacos , Degeneración Retiniana/metabolismo , Sirolimus/farmacología , Animales , Antígenos CD/análisis , Antígenos de Diferenciación Mielomonocítica/análisis , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/patología , Combinación de Medicamentos , Electrorretinografía , Angiografía con Fluoresceína , Fondo de Ojo , Expresión Génica/efectos de los fármacos , Técnicas de Transferencia de Gen , Vectores Genéticos , Proteínas Fluorescentes Verdes , Inmunofenotipificación , Proteínas Luminiscentes/genética , Macrófagos/inmunología , Macrófagos/patología , Ratas , Ratas Mutantes , Retina/metabolismo , Degeneración Retiniana/patología , Degeneración Retiniana/virología , Linfocitos T Citotóxicos/patología , Transgenes
19.
Neurosci Lett ; 312(2): 113-7, 2001 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-11595347

RESUMEN

Rat pups age of 14 postnatal day (P14) were subjected to lithium-pilocarpine (Li-PC) model of status epilepticus (SE). Control rats (n=6) were given an equivalent volume of saline intraperitoneally. Behavioral testing began on P60 including the Morris water maze, the radial arm maze, and the rotarod test. Brain were then analyzed with cresyl violet stain for histological lesions and evaluated for mossy fiber sprouting with the Timm stain. We observed spatial memory deficits both in the Morris water maze and radial arm maze in Li-PC-treated rat. There was no motor impairment in Li-PC-treated rat by the rotarod test. Two of six Li-PC-treated rats showed cell loss in hippocampal CA1 subfield. The Timm staining pattern was similar in both control and Li-PC-treated rats. Result of this study suggests that Li-PC-induced SE in immature rats cause long-term cognitive deficit and permanent cell loss in hippocampal CA1, but spare motor impairment.


Asunto(s)
Envejecimiento/efectos de los fármacos , Epilepsia del Lóbulo Temporal/patología , Hipocampo/crecimiento & desarrollo , Aprendizaje por Laberinto/efectos de los fármacos , Trastornos de la Memoria/patología , Degeneración Nerviosa/patología , Estado Epiléptico/patología , Envejecimiento/fisiología , Animales , Modelos Animales de Enfermedad , Epilepsia del Lóbulo Temporal/fisiopatología , Femenino , Hipocampo/patología , Hipocampo/fisiopatología , Litio/farmacología , Masculino , Aprendizaje por Laberinto/fisiología , Trastornos de la Memoria/inducido químicamente , Trastornos de la Memoria/fisiopatología , Actividad Motora/efectos de los fármacos , Actividad Motora/fisiología , Trastornos del Movimiento/etiología , Trastornos del Movimiento/patología , Trastornos del Movimiento/fisiopatología , Agonistas Muscarínicos/farmacología , Degeneración Nerviosa/inducido químicamente , Degeneración Nerviosa/fisiopatología , Neuronas/efectos de los fármacos , Neuronas/patología , Pilocarpina/farmacología , Ratas , Ratas Sprague-Dawley , Estado Epiléptico/inducido químicamente , Estado Epiléptico/fisiopatología
20.
J Pharm Sci ; 88(5): 489-500, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10229638

RESUMEN

Peptide and protein drugs are often formulated in the solid-state to provide stabilization during storage. However, reactions can occur in the solid-state, leading to degradation and inactivation of these agents. This review summarizes the major chemical reactions affecting proteins and peptides in the solid-state: deamidation, peptide bond cleavage, oxidation, the Maillard reaction, beta-elimination, and dimerization/aggregation. Physical and chemical factors influencing these reactions are also discussed. These include temperature, moisture content, excipients, and the physical state of the formulation (amorphous vs crystalline). The review is intended to serve as an aid for those involved in formulation, and to stimulate further research on the determinants of peptide and protein reactivity in the solid-state.


Asunto(s)
Péptidos/química , Proteínas/química , Concentración de Iones de Hidrógeno , Oxidación-Reducción , Temperatura
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