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981.
Bullying affects approximately 40% of individuals with intellectual and developmental disabilities (IDD). Cyberbullying, a type of bullying facilitated by electronic devices, may be particularly worrisome for parents of children with IDD as constant monitoring is difficult. In this study, ten parents of Special Olympics Maryland athletes completed a survey and participated in in-depth, semi-structured interviews. Interview questions were based on the routine activities theory, whichposits that crime requires a vulnerable target, motivated offender, and lack of effective monitoring. Sixty percent of parents reported that their child with IDD had been bullied at school and, although quantitative analysis indicated no cyberbullying exposure, qualitative analysis implied two children had been cyberbullied. Results suggest parents perceive that individuals with IDD are vulnerable to cyberbullying, require constant monitoring, and have unique resource needs. Cyberbullying is an important health issue for those with IDD; additional research and targeted resources are needed.  相似文献   
982.
Objective:We aimed to investigate whether individuals with first-episode psychosis (FEP) receiving extended early intervention (EI) were less likely to experience suicidal ideation and behaviors than those transferred to regular care after 2 years of EI. Another objective was to examine the 5-year course of suicidality in FEP.Methods:We conducted a secondary analysis of a randomized controlled trial where 220 patients were randomized after 2 years of EI to receive extended EI or regular care for the subsequent 3 years. Suicidality was rated using the Brief Psychiatric Rating Scale. Linear mixed model analysis was used to study time and group effects on suicidality.Results:Extended EI and regular care groups did not differ on suicidality. There was a small decrease in suicidality over time, F(7, 1038) = 1.84, P = 0.077, with an immediate sharp decline within a month of treatment, followed by stability over the remaining 5 years. Patients who endorsed suicidality at entry (46.6%) had higher baseline positive, negative, and depressive symptoms. The 5-year course fell in 3 groups: never endorsed suicidality (33.9%), endorsed suicidality at low-risk levels (43.1%), and endorsed high-risk levels (23.0%). The high-risk group had a higher proportion of affective versus nonaffective psychosis diagnosis; higher baseline positive and depressive symptoms; higher 5-year mean depression scores, and fewer weeks of positive symptom remission over the 5-year course.Conclusions:The first month of treatment is a critical period for suicide risk in FEP. Although early reductions in suicidality are often maintained, our findings make the case for sustained monitoring for suicide risk management.  相似文献   
983.
Primary progressive aphasia (PPA) has been recognized as a syndrome distinct from the usual pattern of language deterioration in Alzheimer??s disease and typically more related to the pathology of frontotemporal dementia (FTD). In recent years, however, the syndromes of primary progressive aphasia have become more complex, divided into the three subtypes of progressive nonfluent aphasia (PNFA), semantic dementia (SD), and logopenic/phonological progressive aphasia (LPA). These syndromes have not only made the linguistic analysis more complex, but the associated pathologies have also become more variable. In particular, PNFA is usually, but not always, associated with FTD pathology and often evidence of a tau mutation, but rarely AD; SD is usually associated with FTD of the ubiquitin staining or progranulin (TAR-DNA) mutation type, but, again, occasionally AD; LPA is typically associated with AD pathology. Patterns of atrophy on magnetic resonance imaging (MRI) generally conform to these subtypes, with PNFA associated with left frontal and insular atophy, SD associated with bilateral temporal atrophy, and LPA associated with L superior-posterior temporal and parietal atrophy. These patterns can also be seen on positron emission (PET) scanning with fluorodeoxyglucose. The newer amyloid binding ligand PET technologies are less useful for detecting regional atrophy patterns but more useful for indication of the underlying pathology. We can thus speak of syndromes of PPA or underlying pathological bases of PPA.  相似文献   
984.

ABSTRACT

BACKGROUND/PURPOSE

To assess correlation between brain lesions and clinical status with 1.5T and 3T magnetic resonance imaging (MRI).

METHODS

Brain MRI fluid‐attenuated inversion‐recovery (FLAIR) sequences were performed in 32 multiple sclerosis (MS) patients. Expanded Disability Status Scale (EDSS) score (mean ± standard deviation) was 2 ± 2.0 (range 0‐8), disease duration 9.3 ± 8.0 (range .8‐29) years.

RESULTS

FLAIR lesion volume (FLLV) at 3T was higher than at 1.5T (P= .01). Correlation between 1.5T FLLV and EDSS score was poor, while 3T FLLV correlated moderately and significantly (rs= .39, P= .03). When controlling for age and depression, correlations between FLLV and cognitive measures were significant at 1.5T for the Judgment of Line Orientation test (JLO) (rs=−.44, P= .05), the Symbol Digit Modalities Test (SDMT) (rs=−.49, P= .02), and the California Verbal Learning Test Delayed Free Recall (CVLT DR) (rs=−.44, P= .04). Correlations at 3T were also significant for these tests, but of greater magnitude: JLO (rs=−.70, P= .0005), SDMT (rs=−.73, P= .0001), CVLT DR (rs=−.061, P= .003). Additional significant correlations obtained only at 3T included the 2 second‐paced auditory serial addition test (rs=−.55, P= .01), the Brief Visuospatial Memory Test‐Delayed Free Recall (rs=−.56, P= .007), and the California Verbal Learning Test Total Recall (rs=−.42, P= .05).

CONCLUSION

MRI at 3T may boost sensitivity and improve validity in MS brain lesion assessment.
  相似文献   
985.
Indoleamine 2,3-dioxygenase (IDO) is the rate-limiting enzyme in the kynurenine pathway of tryptophan metabolism. IDO activity is linked with immunosuppression by its ability to inhibit lymphocyte proliferation, and with neurotoxicity through the generation of quinolinic acid and other toxins. IDO is induced in macrophages by HIV-1 infection, and it is up regulated in macrophages in human brain tissue with HIV-1 encephalitis (HIVE). Using a model of HIVE, we investigated whether IDO inhibitor 1-methyl-d-tryptophan (1-MT) could affect the generation of cytotoxic T lymphocytes (CTLs) and clearance of virus-infected macrophages from the brain. Severe combined immunodeficient mice were reconstituted with human peripheral blood lymphocytes, and encephalitis was induced by intracranial injection of autologous HIV-1-infected monocyte-derived macrophages (MDMs). Animals treated with 1-MT demonstrated increased numbers of human CD3+, CD8+, CD8+/interferon-gamma+ T cells, and HIV-1(gag/pol)-specific CTLs in peripheral blood compared with controls. At week 2 after MDM injection in the basal ganglia, mice treated with 1-MT showed a 2-fold increase in CD8+ T lymphocytes in the areas of the brain containing HIV-1-infected MDMs compared with untreated controls. By week 3, 1-MT-treated mice showed 89% reduction in HIV-infected MDMs in brain as compared with controls. Thus, manipulation of immunosuppressive IDO activity in HIVE may enhance the generation of HIV-1-specific CTLs, leading to elimination of HIV-1-infected macrophages in brain.  相似文献   
986.
Autologous immature myoblasts are obtained from biopsy of thigh muscle. These cells are cultured to a thera peutic dosage at a central Good Manufacture Practic (cGMP) facility. The cells are suspended in a special solu tion which preserves their shelf lif…  相似文献   
987.
The exact mechanisms of deposition and accumulation of amyloid in senile plaques and in blood vessels in Alzheimer's disease remain unknown. Heparan sulfate proteoglycans may play an important role in amyloid deposition in Alzheimer's disease. Previous investigations have demonstrated high affinity binding between heparan sulfate proteoglycans and the amyloid precursor, as well as with the A4 peptide. In the current studies, a specific vascular heparan sulfate proteoglycan found in senile plaques bound with high affinity to two amyloid protein precursors (APP695 and APP770). Vascular heparan sulfate proteoglycan also bound the Alzheimer's amyloid A4 peptide, and not other amyloid protein precursor regions studied, with high affinity. Both heparan sulfate glycosaminoglycan chains and chemically deglycosylated vascular heparan sulfate proteoglycan protein core bound to A4. High affinity interactions between vascular heparan sulfate proteoglycan and the A4 peptide may play a role in the process of amyloidogenesis in Alzheimer's disease, by localizing the site of deposition of A4, protecting A4 from further proteolysis, or by promoting aggregation and fibril formation.  相似文献   
988.
989.
This paper discusses the problems arising from the multidisciplinary nature of cognitive research and the need to conceptually unify insights from multiple fields into the phenomena that drive cognition. Specifically, the Fundamental Code Unit (FCU) is proposed as a means to better quantify the intelligent thought process at multiple levels of analysis. From the linguistic and behavioral output, FCU produces to the chemical and physical processes within the brain that drive it. The proposed method efficiently model the most complex decision-making process performed by the brain.  相似文献   
990.
Two cases of squamous carcinoma of the anus in white homosexual men aged 36 and 47 years are reported, each with a short history of rapidly enlarging perianal lesions. Immunological studies showed that both men had pronounced T helper lymphocyte depletion, and antibody to human T cell lymphotropic virus type III (HTLV-III) was detected in both patients. In addition one patient had a long history of wart virus infection of the anal canal. The diminished cellular immunity associated with HTLV-III may have been responsible for the development of the squamous carcinoma, either directly or by its association with human papilloma virus infection.  相似文献   
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