Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 61
Filter
1.
Malays Orthop J ; 16(1): 130-133, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35519533

ABSTRACT

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.

2.
Ann Burns Fire Disasters ; 34(3): 264-276, 2021 Sep 30.
Article in English | MEDLINE | ID: mdl-34744543

ABSTRACT

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.

3.
J Transl Med ; 18(1): 14, 2020 01 09.
Article in English | MEDLINE | ID: mdl-31918710

ABSTRACT

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.


Subject(s)
Artificial Intelligence , Delivery of Health Care , France , Humans , Public Opinion , Surveys and Questionnaires
4.
Acta Psychiatr Scand ; 138(5): 379-400, 2018 11.
Article in English | MEDLINE | ID: mdl-29904907

ABSTRACT

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.


Subject(s)
Anxiety Disorders/therapy , Attention Deficit Disorder with Hyperactivity/therapy , Autism Spectrum Disorder/therapy , Communication Disorders/therapy , Mood Disorders/therapy , Practice Guidelines as Topic , Psychomotor Agitation/therapy , Sleep Wake Disorders/therapy , Stereotyped Behavior , Adolescent , Anxiety Disorders/etiology , Attention Deficit Disorder with Hyperactivity/etiology , Autism Spectrum Disorder/complications , Child , Communication Disorders/etiology , Humans , Mood Disorders/etiology , Psychomotor Agitation/etiology , Sleep Wake Disorders/etiology
5.
Transl Psychiatry ; 7(4): e1090, 2017 04 11.
Article in English | MEDLINE | ID: mdl-28398337

ABSTRACT

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.


Subject(s)
Autism Spectrum Disorder/diagnostic imaging , Autism Spectrum Disorder/pathology , Diffusion Tensor Imaging , Frontal Lobe/diagnostic imaging , Frontal Lobe/pathology , Neural Pathways/diagnostic imaging , Neural Pathways/pathology , Adolescent , Adult , Case-Control Studies , Female , Humans , Male , Middle Aged , Sex Factors , Young Adult
6.
Transl Psychiatry ; 7(4): e1099, 2017 04 18.
Article in English | MEDLINE | ID: mdl-28418398

ABSTRACT

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.


Subject(s)
Cerebral Cortex/drug effects , Connectome , Corpus Striatum/drug effects , Nerve Net/drug effects , Administration, Intranasal , Adult , Affect/drug effects , Cerebral Cortex/diagnostic imaging , Communication , Corpus Striatum/diagnostic imaging , Double-Blind Method , Female , Gene Expression/drug effects , Humans , Magnetic Resonance Imaging , Middle Aged , Motivation/drug effects , Nerve Net/diagnostic imaging , Receptors, Oxytocin/genetics , Social Behavior , Young Adult
7.
Psychol Med ; 47(4): 639-654, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27825394

ABSTRACT

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.


Subject(s)
Autism Spectrum Disorder , Cerebral Cortex/physiopathology , Connectome/methods , Endophenotypes , Gray Matter/pathology , Siblings , White Matter/pathology , Adolescent , Adult , Autism Spectrum Disorder/diagnostic imaging , Autism Spectrum Disorder/pathology , Autism Spectrum Disorder/physiopathology , Cerebral Cortex/diagnostic imaging , Child , Gray Matter/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , White Matter/diagnostic imaging , Young Adult
8.
Phys Rev E ; 93(5): 053114, 2016 May.
Article in English | MEDLINE | ID: mdl-27300985

ABSTRACT

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.

9.
Psychol Med ; 46(12): 2561-9, 2016 09.
Article in English | MEDLINE | ID: mdl-27345441

ABSTRACT

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.


Subject(s)
Attention Deficit Disorder with Hyperactivity/pathology , Attention Deficit Disorder with Hyperactivity/physiopathology , Gray Matter/pathology , Time Perception/physiology , Adult , Attention Deficit Disorder with Hyperactivity/diagnostic imaging , Endophenotypes , Female , Gray Matter/diagnostic imaging , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Nuclear Family , Young Adult
10.
Cereb Cortex ; 26(7): 3297-309, 2016 07.
Article in English | MEDLINE | ID: mdl-27130663

ABSTRACT

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.


Subject(s)
Autism Spectrum Disorder/diagnostic imaging , Cerebral Cortex/diagnostic imaging , Gray Matter/diagnostic imaging , White Matter/diagnostic imaging , Adolescent , Adult , Diffusion Tensor Imaging , Humans , Imaging, Three-Dimensional , Intelligence , Magnetic Resonance Imaging , Male , Neural Pathways/diagnostic imaging , Organ Size , Pattern Recognition, Automated , Young Adult
11.
Article in English | MEDLINE | ID: mdl-26651631

ABSTRACT

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.


Subject(s)
Amoeba/physiology , Models, Biological , Movement , Swimming
12.
Transl Psychiatry ; 5: e529, 2015 Mar 17.
Article in English | MEDLINE | ID: mdl-25781228

ABSTRACT

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.


Subject(s)
Adolescent Development/physiology , Autistic Disorder/pathology , Phenotype , White Matter/pathology , Adolescent , Adult , Age Factors , Child , Diffusion Tensor Imaging , Endophenotypes , Female , Humans , Male , Siblings , Young Adult
13.
Psychol Med ; 44(15): 3215-27, 2014 Nov.
Article in English | MEDLINE | ID: mdl-25065819

ABSTRACT

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.


Subject(s)
Brain/physiopathology , Child Development Disorders, Pervasive/physiopathology , Facial Expression , Siblings , Theory of Mind/physiology , Adolescent , Endophenotypes , Eye , Female , Humans , Magnetic Resonance Imaging , Male , Sex Factors
14.
AJNR Am J Neuroradiol ; 33(1): 83-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22173769

ABSTRACT

BACKGROUND AND PURPOSE: It has been proposed that autism spectrums condition may represent a form of extreme male brain (EMB), a notion supported by psychometric, behavioral, and endocrine evidence. Yet, limited data are presently available evaluating this hypothesis in terms of neuroanatomy. Here, we investigated sex-related anatomic features in adults with AS, a "pure" form of autism not involving major developmental delay. MATERIALS AND METHODS: Males and females with AS and healthy controls (n = 28 and 30, respectively) were recruited. Structural MR imaging was performed to measure overall gray and white matter volume and to assess regional effects by means of VBM. DTI was used to investigate the integrity of the main white matter tracts. RESULTS: Significant interactions were found between sex and diagnosis in total white matter volume, regional gray matter volume in the right parietal operculum, and fractional anisotropy (FA) in the body of the CC, cingulum, and CR. Post hoc comparisons indicated that the typical sexual dimorphism found in controls, whereby males have larger FA and total white matter volume, was absent or attenuated in participants with AS. CONCLUSIONS: Our results point to a fundamental role of the factors that underlie sex-specific brain differentiation in the etiology of autism.


Subject(s)
Algorithms , Autistic Disorder/pathology , Brain/pathology , Diffusion Magnetic Resonance Imaging/methods , Image Interpretation, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Adult , Autistic Disorder/classification , Female , Humans , Image Enhancement/methods , Male , Reproducibility of Results , Sensitivity and Specificity , Sex Factors
15.
Neurosci Lett ; 312(2): 113-7, 2001 Oct 19.
Article in English | MEDLINE | ID: mdl-11595347

ABSTRACT

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.


Subject(s)
Aging/drug effects , Epilepsy, Temporal Lobe/pathology , Hippocampus/growth & development , Maze Learning/drug effects , Memory Disorders/pathology , Nerve Degeneration/pathology , Status Epilepticus/pathology , Aging/physiology , Animals , Disease Models, Animal , Epilepsy, Temporal Lobe/physiopathology , Female , Hippocampus/pathology , Hippocampus/physiopathology , Lithium/pharmacology , Male , Maze Learning/physiology , Memory Disorders/chemically induced , Memory Disorders/physiopathology , Motor Activity/drug effects , Motor Activity/physiology , Movement Disorders/etiology , Movement Disorders/pathology , Movement Disorders/physiopathology , Muscarinic Agonists/pharmacology , Nerve Degeneration/chemically induced , Nerve Degeneration/physiopathology , Neurons/drug effects , Neurons/pathology , Pilocarpine/pharmacology , Rats , Rats, Sprague-Dawley , Status Epilepticus/chemically induced , Status Epilepticus/physiopathology
16.
Int J Syst Evol Microbiol ; 51(Pt 5): 1873-1880, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11594621

ABSTRACT

A novel methanogen, designated strain N2F9704T, was isolated from an aquaculture fish pond near Wang-gong, Taiwan. The cells were irregular cocci, non-motile, 1.2-2.0 microm in diameter and stained gram-negative. Cells of strain N2F9704T lysed easily by SDS treatment (0.1 g l(-1)) and the S-layer protein had an Mr of 137000. The catabolic substrates used included formate and H2+CO2, but not acetate, methanol, trimethylamine or secondary alcohols. The optimal growth parameters for strain N2F9704T were pH 6.5, 37 degrees C with 0.5% NaCl. Trace amounts of tungstate not only promoted growth but also extended the range of growth conditions. Analysis of the 16S rDNA sequence revealed a phylogenetic relationship to Methanofollis species and the name Methanofollis aquaemaris sp. nov. is therefore proposed for strain N2F9704T (= OCM 746T = CCRC 16166T). Additionally, the strain was infected with a novel coccus-shaped, enveloped virus with a diameter of 200 nm.


Subject(s)
Fisheries , Methanomicrobiaceae/classification , Methanomicrobiaceae/isolation & purification , Water Microbiology , Anti-Bacterial Agents/pharmacology , Culture Media , DNA, Ribosomal/analysis , Methanomicrobiaceae/genetics , Methanomicrobiaceae/growth & development , Methanomicrobiaceae/ultrastructure , Microscopy, Electron, Scanning , Molecular Sequence Data , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
17.
Proc Natl Acad Sci U S A ; 98(18): 10154-9, 2001 Aug 28.
Article in English | MEDLINE | ID: mdl-11517331

ABSTRACT

Serine/arginine-rich proteins (SR proteins) are a family of nuclear factors that play important roles in both constitutive and regulated precursor mRNA splicing. The domain rich in arginine/serine (RS) repeats (RS domain) serves as both a nuclear and subnuclear localization signal. We previously identified an importin beta family protein, transportin-SR2 (TRN-SR2), that specifically interacts with phosphorylated RS domains. A TRN-SR2 mutant deficient in Ran binding colocalizes with SR proteins in nuclear speckles, suggesting a role of TRN-SR2 in nuclear targeting of SR proteins. Using in vitro import assays, we here show that nuclear import of SR protein fusions requires cytosolic factors, and that the RS domain becomes phosphorylated in the import reaction. Reconstitution of SR protein import by using recombinant transport factors clearly demonstrates that TRN-SR2 is capable of targeting phosphorylated, but not unphosphorylated, SR proteins to the nucleus. Therefore, RS domain phosphorylation is critical for TRN-SR2-mediated nuclear import. Interestingly, we found that the RNA-binding activity of SR proteins confers temperature sensitivity to their nuclear import. Finally, we show that TRN-SR2 interacts with a nucleoporin and is targeted not only to the nuclear envelope but also to nuclear speckles in vitro. Thus, TRN-SR2 may perhaps escort SR protein cargoes to nuclear subdomains.


Subject(s)
Nuclear Proteins/metabolism , Phosphoproteins/metabolism , Receptors, Cytoplasmic and Nuclear/metabolism , beta Karyopherins , Active Transport, Cell Nucleus , Amino Acid Sequence , HeLa Cells , Humans , Membrane Glycoproteins/metabolism , Mutation , Nuclear Pore Complex Proteins , Nuclear Proteins/chemistry , Nuclear Proteins/genetics , Phosphoproteins/chemistry , Phosphoproteins/genetics , Phosphorylation , RNA/metabolism , RNA Splicing , RNA-Binding Proteins , Receptors, Cytoplasmic and Nuclear/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Serine-Arginine Splicing Factors , Temperature
18.
Arch Ophthalmol ; 119(7): 1033-43, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11448325

ABSTRACT

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.


Subject(s)
Adenoviridae/genetics , Cyclosporine/pharmacology , Immunosuppressive Agents/pharmacology , Luminescent Proteins/metabolism , Retina/drug effects , Retinal Degeneration/metabolism , Sirolimus/pharmacology , Animals , Antigens, CD/analysis , Antigens, Differentiation, Myelomonocytic/analysis , CD4-Positive T-Lymphocytes/pathology , CD8-Positive T-Lymphocytes/pathology , Drug Combinations , Electroretinography , Fluorescein Angiography , Fundus Oculi , Gene Expression/drug effects , Gene Transfer Techniques , Genetic Vectors , Green Fluorescent Proteins , Immunophenotyping , Luminescent Proteins/genetics , Macrophages/immunology , Macrophages/pathology , Rats , Rats, Mutant Strains , Retina/metabolism , Retinal Degeneration/pathology , Retinal Degeneration/virology , T-Lymphocytes, Cytotoxic/pathology , Transgenes
19.
Curr Microbiol ; 42(6): 432-7, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11381337

ABSTRACT

A new methanogen, designated as strain P2F9701a (= OCM 745), was isolated from a water sample of estuarine environment in Elrin Shi, Taiwan. Cells of strain P2F9701a were motile coccus (0.7 approximately 1.1 micron) with tufts of flagella. Gas vacuoles were observed, and the protein cell wall was composed of S-layer protein subunit with Mr of 74,700. Cells catabolized formate and H2+CO2 to produce methane, but not acetate, methanol, and trimethylamine. Strain P2F9701a grew in the range of 30-42 degrees C, with optimal growth temperature at 37 degrees C, but did not grow below 28 degrees C or above 42 degrees C. This estuarine isolate P2F9701a tolerated well the NaCl concentration between 0.02 and 1.03 m, and the optimal salt for growth was 0.17 m. Although phylogenetic analytic results indicated that P2F9701a belongs to the mesophilic, hydrogenotrophic marine methanogen of Methanococcus voltaei, the occurrence of gas vacuoles, tufts of flagella, eury-halotolerant and steno-thermotolerant characters of strain P2F9701a are different from mesophilic Methanococcus spp. that had been reported.


Subject(s)
Methanococcus/classification , Methanococcus/isolation & purification , Hydrogen/metabolism , Hydrogen-Ion Concentration , Methanococcus/growth & development , Methanococcus/ultrastructure , Phylogeny , Water Microbiology
20.
Clin Exp Ophthalmol ; 28(3): 216-9, 2000 Jun.
Article in English | MEDLINE | ID: mdl-10981803

ABSTRACT

In this work a novel enzyme-linked immunoabsorbent assay quantifying residual rod outer segments in the medium of rod outer segment-challenged retinal pigment epithelial cells is described. A retinal pigment epithelial cell line (D407) that produces low level of cathepsin D, and a primary human retinal pigment epithelial cell culture (HRPE51) that has normal cathepsin D levels, were challenged with bovine rod outer segments. At 3 days post-challenge, the amount of undigested or residual bovine rod outer segments left in the culture medium was quantified by an enzyme-linked immunoabsorbent assay. An antibody raised against bovine rod outer segments, which had been purified and labelled with nitroiodophenyl haptens, was used in the assay. The sensitivity of the immunoassay was less than 10(2) bovine rod outer segments per mL and the signal followed a linear curve, saturating around 10(6) bovine rod outer segments per mL. HRPE51 cells had no residual bovine rod outer segments present in the medium following a challenge with 10(4) bovine rod outer segments per mL. In the medium of D407 cells, residual bovine rod outer segment levels were higher at all bovine rod outer segment concentrations when compared to the residual bovine rod outer segment levels in HRPE51 cells, suggesting that D407 cells have a lower digestive capacity. These results demonstrated that the immunoassay for detecting bovine rod outer segments is a sensitive and reliable technique that can be used to quantify the amount of residual bovine rod outer segments, following bovine rod outer segment challenge of retinal pigment epithelial cells.


Subject(s)
Enzyme-Linked Immunosorbent Assay/methods , Phagocytosis/physiology , Pigment Epithelium of Eye/physiology , Rod Cell Outer Segment/metabolism , Animals , Blotting, Western , Cathepsin D/metabolism , Cattle , Cells, Cultured , Immunoglobulin G/immunology , Pigment Epithelium of Eye/enzymology , Rabbits , Rod Cell Outer Segment/immunology
SELECTION OF CITATIONS
SEARCH DETAIL
...