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31.
PURPOSE: Inclusion-body myopathy, Paget's disease of bone and frontotemporal dementia is an adult-onset autosomal dominant illness (IBMPFD) caused by mutations in the valosin-containing protein (VCP) on chromosome 9p21.1-p12. The penetrance of the gene is 82% for myopathy, 49% for Paget's disease, but may be as low as 30% for frontotemporal dementia. Modifier genes could account for decreased frontotemporal dementia penetrance. In this study apolipoprotein-E (APOE) was evaluated for this role in IBMPFD families based on its known modifier effect in Alzheimer's disease. METHODS: From a database of 231 members of 15 families, 174 had APOE genotype available for analysis. Logistic regressions on APOE genotype and frontotemporal dementia were performed, using appropriate covariates. RESULTS AND CONCLUSION: FTD was associated with APOE 4 genotype (P=0.0002), myopathy (P=0.0006), and age (P=0.01), but not microtubule associated protein tau (MAPT) H2 haplotype (P=0.5) or gender (0.09) after adjustment for membership in pedigrees with at least one APOE 4 genotype. These data suggest a potential link between APOE 4 genotype and the specific form of frontotemporal dementia found in IBMPFD. The molecular basis of this link bears further investigation. We did not observe an association of frontotemporal dementia and H2 MAPT haplotype.  相似文献   
32.
PCR-SSOP identification procedures for IL-2, IL-6, IL-10, TNF-alpha and TNF-beta cytokine polymorphisms have been developed. Application of the procedures to a range of diverse geographically distributed populations has identified ethnic differences within the groups studied. Five populations were investigated, Northern Ireland, South African Zulu, Omani, Singapore Chinese and Mexican Mestizos.  相似文献   
33.
Three-day-old rats were bilaterally dopamine-depleted with 6-hydroxydopamine and 3 days later cell suspensions derived from the dopamine-rich ventral mesencephalic area were injected into the right rostral striatum. The transplants rapidly developed a substantial innervation of one striatum, so that by 15 days after transplantation (21 days of age) animals rotated away from the reinnervated side in response to amphetamine. The amount of turning correlated with the extent of innervation of the striatum as determined by tyrosine hydroxylase immunocytochemistry. By 25 days post-transplantation (31 days of age), animals turned in response to stress as well as amphetamine, although this later-developing phenomenon was not associated with any significant change in the extent of dopamine innervation.

A second group of animals was bilaterally dopamine-depleted at 3 days of age, but transplantation with nigral cell suspensions was delayed until maturity. Partial reinnervation of the rostral striatum occurred with this delayed transplant paradigm, and turning to both amphetamine and stress commenced at 15 days post-transplantation. In contrast to animals receiving transplants shortly after lesioning, these animals began to turn spontaneously at about 20 days post-transplantation. The serotonin hyper-innervation that occurs following dopamine depletion in infancy was not altered by dopamine transplants made at either time.

Results from both groups of transplant animals suggest that dopamine-rich transplants can provide substantial innervation that exerts some functional control over the striatum. This occurs despite the fact that neonatally dopamine-depleted rats, unlike adult-lesioned animals, survive quite well in the absence of striatal dopamine. However, the degree of incorporation into existing circuitry, and the types of regulation that result, may vary considerably depending on the age at which the tissue is transplanted.  相似文献   

34.
DNA microarray profiling of CD4(+) and CD8(+) cells from non-treated relapsing and remitting multiple sclerosis (MS) patients determined that the cytoplasmic binding partner of fragile X protein (CYFIP2, also called PIR121) was increased significantly compared to healthy controls. Western analysis confirmed that CYFIP2 protein was increased approximately fourfold in CD4(+) cells from MS compared to inflammatory bowel disorder (IBD) patients or healthy controls. Because CYFIP2 acts as part of a tetrameric complex that regulates WAVE1 activation we hypothesized that high levels of CYFIP2 facilitate T cell adhesion, which is elevated in MS patients. Several findings indicated that increased levels of CYFIP2 facilitated adhesion. First, adenoviral-mediated overexpression of CYFIP2 in Jurkat cells increased fibronectin-mediated adhesion. Secondly, CYFIP2 knock-down experiments using antisense oligodeoxynucleotides reduced fibronectin-mediated binding in Jurkat and CD4(+) cells. Thirdly, inhibition of Rac-1, a physical partner with CYFIP2 and regulator of WAVE1 activity, reduced fibronectin-mediated adhesion in Jurkat and CD4(+) cells. Finally, inhibition of Rac-1 or reduction of CYFIP2 protein decreased fibronectin-mediated adhesion in CD4(+) cells from MS patients to levels similar to controls. These studies suggest that overabundance of CYFIP2 protein facilitates increased adhesion properties of T cells from MS patients.  相似文献   
35.
Polyclonal hypergammaglobulinemia is a characteristic of chronic inflammatory conditions, including persisting viral infections and autoimmune diseases. Here we have studied hypergammaglobulinemia in mice infected with lymphocytic choriomeningitis virus (LCMV), which induces nonspecific immunoglobulins as a result of switching natural IgM specificities to IgG. The process is dependent on help from CD4+ T cells that specifically recognize LCMV peptides presented by B cells on major histocompatibility complex class II molecules. Thus, hypergammaglobulinemia may arise when specific helper T cells recognize B cells that have processed viral antigens irrespective of the B cell receptor specificity. This nonspecific B cell activation may contribute to antibody-mediated autoimmunity.  相似文献   
36.
37.
BACKGROUND: The Inhaled Steroid Treatment as Regular Therapy in Early Asthma (START) study is a worldwide, randomized, prospective study to investigate early intervention with inhaled corticosteroids in recent-onset mild persistent asthma. OBJECTIVE: To evaluate the safety and tolerability of long-term treatment with once-daily budesonide therapy in patients with mild persistent asthma. METHODS: Patients aged 5 to 66 years with mild persistent asthma for fewer than 2 years and no previous regular corticosteroid treatment received budesonide or placebo once daily for 3 years, in addition to their usual asthma therapy. The daily budesonide dose was 200 microg for children younger than 11 years and 400 microg for those 11 years or older. RESULTS: Overall, 7,221 patients were included in the safety analysis, and a total of 21,520 adverse events were reported (10,850 in the budesonide group and 10,670 in the placebo group). The most commonly reported events included respiratory infections, rhinitis, pharyngitis, bronchitis, viral infections, and sinusitis. The number of deaths and serious adverse events were similar for children and adults in both treatment groups. Fewer asthma-related serious adverse events were reported with budesonide (162) compared with placebo (276). Oral candidiasis was reported more frequently with budesonide (1.2%) than with placebo (0.5%); the frequencies of other adverse effects previously reported to be associated with inhaled corticosteroids (psychiatric disorders, skin disorders, and allergic reactions) were similar. CONCLUSIONS: Three-year treatment with budesonide once daily (200 or 400 microg) is safe and well tolerated in children and adults with newly detected mild persistent asthma.  相似文献   
38.
Systemically administered DNA encoding a recombinant human immunodeficiency virus (HIV) derived immunogen effectively primes a cytotoxic T lymphocyte (CTL) response in macaques. In this further pilot study we have evaluated mucosal delivery of DNA as an alternative priming strategy. Plasmid DNA, pTH.HW, encoding a multi-CTL epitope gene, was incorporated into poly(D,L-lactic-co-glycolic acid) microparticles of less than 10 microm in diameter. Five intrarectal immunizations failed to stimulate a circulating vaccine-specific CTL response in 2 Mamu-A*01(+) rhesus macaques. However, 1 week after intradermal immunization with a cognate modified vaccinia virus Ankara vaccine MVA.HW, CTL responses were detected in both animals that persisted until analysis postmortem, 12 weeks after the final boost. In contrast, a weaker and less durable response was seen in an animal vaccinated with the MVA construct alone. Analysis of lymphoid tissues revealed a disseminated CTL response in peripheral and regional lymph nodes but not the spleen of both mucosally primed animals.  相似文献   
39.
The role of adjuvant on the T(h)1 and T(h)2 immune responses to Abeta-immunotherapy (Abeta(42 )peptide) was examined in wild-type mice. Fine epitope analysis with overlapping oligomers of the Abeta(42) sequence identified the 1-15 region as a dominant B cell epitope. The 6-20 peptide was recognized only weakly by antisera from mice administrated with Abeta(42) peptide formulated in complete Freund's adjuvant (CFA), alum or TiterMax Gold (TMG). However, mice immunized with Abeta(42) mixed with QS21 induced a significant antibody response to the 6-20 peptide. The only T cell epitope found was within the 6-28 sequence of Abeta(42). QS21 and CFA induced the strongest humoral response to Abeta, alum was intermediate, and TMG the weakest adjuvant. Analysis of antibody isotypes specific for Abeta indicates that alum induces primarily T(h)2-type immune response, whereas TMG, CFA and QS21 shift the immune responses toward a T(h)1 phenotype. Stimulation of splenocytes from Abeta-immunized mice with Abeta(40) peptide induced strikingly different cytokine expression profiles. QS21 and CFA induced significant IFN-gamma, IL-4 and tumor necrosis factor-alpha expression, whereas alum induced primarily IL-4 production. As T(h)1-type immune responses have been implicated in many autoimmune disorders, whereas T(h)2-type responses have been shown to inhibit autoimmune disease, the choice of adjuvant may be critical for the design of a safe and effective immunotherapy for Alzheimer's disease.  相似文献   
40.
Remodeling of the chromatin network plays an important role regulating embryonic development as well as differentiation. The SWI/SNF complex is an ATP-dependent chromatin-remodeling complex. It consists of several proteins, including an ATPase subunit, either Brg1 or Brm. Two subunits of this complex, Baf53a and Baf45, have been previously identified as being neural progenitor-specific. In this study, we show that Baf60c, another important part of this large complex, acts in a similar neural progenitor-specific manner. We show that during development Baf60c is expressed in neural progenitors in human retinas as well as mouse retina, cortex and spinal cord. Baf60c expression is lost during neural differentiation and its overexpression keeps the progenitors in a proliferative state through its interaction with the Notch pathway. Finally, we show that Baf60c is re-expressed in the Müller glial cells that re-enter the cell cycle after neurotoxic damage.  相似文献   
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