The nature of the putative autoantigen in Graves' ophthalmopathy (Go) remains an enigma but the sequence similarity between thyroglobulin (Tg) and acetylcholinesterase (ACHE) provides a rationale for ...epitopes which are common to the thyroid gland and the eye orbit. In an attempt to define the shared epitope, we have screened a lambda gt 11 human thyroid cDNA library using a polyclonal antibody to Torpedo ACHE and isolated two clones, which upon sequencing, were shown to contain Tg segments, corresponding to portions of the C terminal part of the molecule which has a high similarity with ACHE. Having demonstrated the existence of an epitope common to Tg and ACHE, the clones have been further tested and found to be positive in lysis plaque assays with 1/10 sera from patients with Hashimoto's thyroiditis (HT), 8/8 from patients with Graves' ophthalmopathy and 0/8 normal sera. We have investigated the physiological significance of this common epitope by in situ immunolocalization studies in which the polyclonal antibody to Torpedo ACHE (which was used for screening the library) and immunoglobulins (Igs) from 6 Go patients tested were shown to bind to end plate regions of human foetal muscle fibres which were concurrently shown to be rich in cholinesterase activity: Igs from 3 normal individuals and 2 patients with Hashimoto's thyroiditis did not bind. The results demonstrate and characterize an epitope which is common to Tg and ACHE and show that Go patients Igs contain antibodies which bind to muscle end plates rich in cholinesterase. The significance of these findings to the pathogenesis of Go is discussed.
The authors used data from an earlier nonblind study to identify 16 autistic-type child outpatients who had apparently improved when given vitamin B6 (pyridoxine). In a double-blind study each ...child's B6 supplement was replaced during two separate experimental trial periods with either a B6 supplement or a matched placebo. Behavior was rated as deteriorating significantly during the B6 withdrawal.
To investigate the therapeutic potential of bone marrow transplantation in Duchenne muscular dystrophy, green fluorescent protein-positive (GFP
+) bone marrow cells were transplanted into irradiated ...wild-type and dystrophin-deficient
mdx
mice. Tibialis anterior muscles showed fivefold to sixfold more GFP
+ mononucleated cells and threefold to fourfold more GFP
+ myofibers in
mdx
than in wild-type mice. In contrast, dystrophin expression in
mdx
mice remained within the level of nontransplanted
mdx
mice, and co-expression with GFP was rare. Longitudinal sections of 5000 myofibers showed 160 GFP
+ fibers, including 9 that co-expressed dystrophin. GFP was always visualized as full-length sarcoplasmic fluorescence that exceeded the span of sample length (up to 1500 μm), whereas dystrophin expression was restricted to 11 to 28% of this length. Dystrophin expression span was much shorter in GFP
+ fibers (116 ± 46 μm) than in revertant fibers (654 ± 409 μm). These data suggest that soluble GFP diffuses far from the fusion site with a pre-existing dystrophin
− myofiber whereas dystrophin remains mainly expressed close to the site of fusion. Because restoration of dystrophin in whole muscle fiber length is required to expect functional improvement and clinical benefits for Duchenne muscular dystrophy, future applications of cell therapies to neuromuscular disorders could be more appropriately envisaged for replacement of defective soluble sarcoplasmic proteins.
1. We analyzed the mode of attachment of 16 S tailed acetylcholinesterase (AChE; EC 3.1.1.7) to rat superior cervical ganglion (SCG) neuronal membranes. Using extractions by high-salt (HS) and ...nonionic detergent (Triton X-100), we found two pools of 16 S AChE. 2. The detergent-extracted (DE) 16 S AChE was tightly bound to membranes through detergent-sensitive, high-salt insensitive interactions and was distinct from high-salt-soluble 16 S AChE. The detergent-extracted (DE) 16 S AChE constituted a significant proportion of about one-third of the total 16 S AChE. 3. Treatment of the neuronal membranes by a phosphatidylinositol-specific phospholipase C (PIPLC) resulted in the release of some, but not all DE 16 S AChE, indicating that a significant amount of the neuronal DE 16 S AChE, about one-third, is anchored to membranes through a phosphatidylinositol containing residue. Thus, a covalent association of a glycolipid and catalytic or structural AChE polypeptidic chains occurs not only for dimeric AChE but also for the asymmetric species of AChE. 4. The complex polymorphism of AChE is due not only to different globular or asymmetric associations of catalytic and structural subunits but also to the alternative existence of a transmembrane domain or a glycolipid membrane anchor.
1. To approach the involvement of tissue-specific elements in the compartmentalization of ubiquitous polymorphic proteins, immunohistochemical methods were used to analyze the localization of ...butyrylcholinesterase (BuChE) in Xenopus oocytes microinjected with synthetic BuChEmRNA alone and in combination with tissue-extracted mRNAs. 2. When injected alone BuChEmRNA efficiently directed the synthesis of small membrane-associated accumulations localized principally on the external surface of the oocyte's animal pole. Tunicamycin blocked the appearance of such accumulations, suggesting that glycosylation is involved in the transport of nascent BuChE molecules to the oocyte's surface. Coinjection with brain or muscle mRNA, but not liver mRNA, facilitated the formation of pronounced, tissue-characteristic BuChE aggregates. 3. These findings implicate tissue-specific mRNAs in the assembly of the clone-produced protein and in its nonuniform distribution in the oocyte membrane or extracellular material.
Several manufacturing firms were surveyed to find answers to questions about their manufacturing quality, and to determine what activities they were using in achieving quality products. Firms of all ...sizes were queried and smaller firms were compared to larger firms. Attempts at finding significant differences between small and large firms were successful. The responses of the larger firms demonstrated that significant differences exist when compared to the smaller firms in a variety of continuous improvement activities that are a part of the process used to achieve higher levels of quality.
Acetylcholinesterase (AChE) is composed of several distinct molecular forms, which are identified and partly resolved by velocity sedimentation analysis on sucrose gradients. We made the assumption ...that each AChE form sediments as a peak of activity with a gaussian shape in the continuous sucrose gradient. We experimentally demonstrate that the complex AChE profiles can be decomposed in gaussian distributions of separate molecular entities. We performed a high salt-detergent extraction of AChE from mouse skeletal muscle and isolated fractions enriched in each particular from. These fractions were then submitted to a second sedimentation, to assess the stability and to further characterize each AChE form. Then, we calculated the statistical significance level of each AChE form and identified up to 9 separate molecular specifies in mouse adult muscle. These forms are the major "4 S", "6.5 S", "10 S", "12 S" and "16 S" and minor molecular active components of AChE. These results suggest complex structural interactions between catalytic and non catalytic subunits of AChE and do not simply fit the tailed asymmetric globular model of AChE with six molecular species.
The functional anatomy of the spinal column has mainly been studied in the cadaver. The aim of our study was to determine in vivo the normal axial rotation of the cervical column using computed ...tomography (CT). Sixty subjects, divided into decades from 20 to 80 years of age were studied. The CT protocol comprised an axial cut at the level of the skull base (C0) and at each vertebral level in the neck, in the neutral position (with the nasal septum vertical) and during rotation of the head. To reduce the exposure to irradiation the subjects were divided into two groups: 40 were studied from C0 to the fifth cervical vertebra (C5) with unilateral rotation at C0 of 10 degrees, 20 degrees and 40 degrees (20 rotations to the left and 20 to the right), and 20 subjects were studied from C0 to the first thoracic vertebra (T1) with a maximum rotation at C0 to left and right. The angular position of a vertebra was defined as the anteroposterior axis with reference in the neutral position to the axis of C0, and in rotation was related to its original axis. At each vertebral level the mean angle of rotation and its standard deviation were calculated (n = 30) for the successive intermediate and maximum rotations at C0 level. The rotation of the cervical spine took place mainly at two levels: 58% between C1 and C2 and 24% between C3 and C6. The pairs of vertebrae C0/C1 and C2/C3 provided functional couples where the rotation was minimal.
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