Ultrastructural characterization of the tau-immunoreactive tubules in the oligodendroglial perikarya and their inner loop processes in progressive supranuclear palsy

Coiled bodies and interfascicular threads are conspicuous white matter abnormalities of brains of patients with progressive supranuclear palsy (PSP). Both structures are argyrophilic and immunoreactive for the microtubule-binding protein tau. This report concerns the ultrastructural localization of interfascicular threads and their relationship to coiled bodies in five PSP patients. We showed for the first time that abnormal tubules with a 13- to 15-nm diameter and fuzzy outer contours were the common structures of coiled bodies in the oligodendroglial perikarya and of interfascicular threads. Moreover, the tubules were immunolabeled by anti-tau antibodies. The abnormal tau-positive tubules of interfascicular threads were located in the inner loop of the myelin sheath. Our study further indicated that the thread-like structures in the white matter comprised, at least in part, oligodendroglial processes, and that they were also present in gray matter. We consider that the formation of coiled bodies in the perikarya and of interfascicular threads represents a common cytoskeletal abnormality of the oligodendroglia of PSP patients. Moreover, even though the white matter alterations of PSP resemble those of corticobasal degeneration, there are certain ultrastructural differences in the abnormal oligodendroglial tubules of the two diseases. Received: 4 October 1996 / Accepted: 6 December 1996     

Newborn infant with maternal anti-SSA antibody-induced complete heart block accompanying cardiomyopathy.

Newborn case of maternal anti-SSA antibody-induced congenital complete heart block (CCHB) accompanying cardiomyopathy is presented. Unexpectedly, she died of ventricular tachycardia, not bradycardia, 6 days after birth. Autopsy revealed left ventricular cardiomyopathy with endocardial fibroelastosis. Thus, when evaluating fetal cardiac performance in cases of maternal anti-SSA antibody-induced CCHB, it is necessary to pay attention to myocardial attributes such as endocardial hyperplasia.     

Monitoring the protective effects of minocycline treatment with radiolabeled annexin V in an experimental model of focal cerebral ischemia.

Minocycline is an antibiotic now recognized to have antiapoptotic and antiinflammatory properties. Because of these properties, minocycline may be of benefit in reducing neuronal apoptosis from ischemia and subsequent postischemic inflammation if administered soon after a stroke. We now explore the feasibility of using (99m)Tc-annexin V, an in vivo marker of apoptosis, with SPECT to monitor the antiapoptotic effects of minocycline therapy. METHODS: CB6/F1 adult male mice underwent unilateral distal middle cerebral artery occlusion (dMCA) occlusion and were imaged and sacrificed at 1, 3, 7, or 30 d after injury. Animals were given minocycline (or vehicle) 30 min and 12 h after dMCA occlusion and then given 22.5 mg/kg twice daily for up to 7 d. Before imaging, behavioral tests were performed to evaluate the neurologic function. After imaging, brains were collected for histology and assessed for the degree of apoptosis and microglial activation. RESULTS: (99m)Tc-Annexin V uptake in injured hemispheres was significantly decreased 2- to 3-fold by minocycline at all time points. Minocyline reduced infarct size as seen histologically and improved behavioral indices as late as 30 d. Infarct volume as seen histologically correlated with radiolabeled annexin V uptake seen by SPECT. In situ fluorescent microscopy demonstrated that annexin V bound primarily to neurons at 1 and 3 d, with a shift toward microglia by 7 and 30 d. CONCLUSION: We found that minocycline significantly reduces neuronal apoptosis and infarct size and improves neurologic outcome in mice after acute focal cortical ischemia.     

Improvement in Wound Healing by Epidermal Growth Factor (EGF) Ointment. I. Effect of Nafamostat,Gabexate, or Gelatin on Stabilization and Efficacy of EGF

The healing effect of human epidermal growth factor (hEGF) on open wounds was studied in rats. No improvement in wound healing was found by topical application of EGF alone to open wound sites. We found an ointment containing EGF and a protease inhibitor, nafamostat mesilate or gabexate mesilate, or gelatin accelerated the healing rate of open wounds. Significant increases in the dry weight of the wound site granulation tissue, uronic acid (as an index of acid mucopolysaccharide) and hydroxyproline (as an index of collagen) were observed by treatment with EGF ointment containing nafamostat compared with the controls. The effects of the protease inhibitor on wound healing were dose dependent. Nafamostat was more efficient than gabexate or gelatin on wound healing. The degradation of ¹²⁵I-EGF in wound tissue homogenate was significantly decreased in the presence of a protease inhibitor, such as nafamostat or gabexate, or gelatin. These findings indicate that the stabilization of EGF at the wound site is an important factor in permitting the expression of its healing effects and suggest that the ointment containing EGF and a stabilizing agent would be a suitable dosage form for acceleration of wound repair.     

Radiographic evaluation of periapical status and prevalence of endodontic treatment in an adult Japanese population.

OBJECTIVES: To determine the prevalence of periapical radiolucencies and endodontic treatment in an adult Japanese population. STUDY DESIGN: Periapical status and length of root fillings of 672 adult patients attending Okayama University Hospital of Dentistry were evaluated using full mouth intraoral radiographs. RESULTS: Overall, 87% of the subjects had root-filled teeth, and 70% exhibited an apical radiolucency. Of the 16,232 teeth examined, 21% had been root-filled, and, of these, 40% exhibited an apical radiolucency. Root-filled teeth that were overfilled or that were mandibular incisors had the highest prevalence of apical radiolucencies. CONCLUSIONS: The prevalence of root-filled teeth appears higher in this Japanese population than in Europe or America; however, the ratio of teeth with an apical radiolucency to root-filled teeth was within the range of that reported for other countries. Overfilled teeth and mandibular incisors are most likely to exhibit apical radiolucencies.     

Increase of soluble Fc gamma RIIIa derived from macrophages in plasma from patients with atherosclerosis

Macrophages play a major role in the development of vascular lesions in atherogenesis. The cells express Fc gamma RIIIa(CD16) identical to that in NK cells, but with a cell type-specific glycosylation. In contrast, neutrophils express Fc gamma RIIIb in two allotypes, NA1- and NA2- Fc gamma RIIIb. These Fc gamma RIIIs are released from the cell surface on activation, and these soluble forms(sFc gamma RIII) are present in plasma. In the present study, we measured sFc gamma RIIIaM phi in plasma with Immuno-PCR with newly-developed anti-Fc gamma RIII mAb, MKGR14(mIgM), which recognizes Fc gamma RIIIaM phi specifically. In healthy donors, the level of sFc gamma RIIIaM phi increased with age. In contrast, the sFc gamma RIIIa level correlated with the number of NK cells in peripheral blood, and the level of total sFc gamma RIII(sFc gamma RIIIa plus sFc gamma RIIIb) correlated with the number of neutrophils. There was no correlation among the levels of three sFc gamma RIIIs was observed in healthy donors. The levels of these sFc gamma RIII were significantly increased in patients with coronary artery disease (CAD) compared with age-matched healthy donors. The sFc gamma RIIIaM phi level was related to the number of significant coronary artery stenoses, and correlated with the sFc gamma RIIIa level, total cholesterol, HDL-cholesterol(negatively), LDL to HDL ratio, triglycerides and body mass index. These findings may show that the macrophages are activated during the incipient stage of atherosclerosis, and that sFc gamma RIIIaM phi may serve as predictive marker for atherosclerosis.     

Mcm1 regulates donor preference controlled by the recombination enhancer in Saccharomyces mating-type switching

Switching of Saccharomyces mating type by replacement of sequences at the MAT locus involves a choice between two donors, HML and HMR. MATα cells inhibit recombination along the entire left arm of chromosome III, including HML, whereas MATa cells activate this same region. MATa-dependent activation of HML depends on a small, cis-acting DNA sequence designated the recombination enhancer (RE), located 17 kb centromere-proximal to HML. A comparison of RE sequences interchangeable between Saccharomyces cerevisiae and Saccharomyces carlsbergensis defines a minimum RE of 244 bp. RE activity is repressed in MATα cells by binding of the Matα2–Mcm1 corepressor to a site within the RE. Mutation of the two Matα2 binding sites removes most, but not all, of this repression, and RE chromatin structure in MATα cells becomes indistinguishable from that seen in MATa. Surprisingly, a 2-bp mutation in the Mcm1 binding site completely abolishes RE activity in MATa cells; moreover, RE chromatin structure in the MATa mutant becomes very similar to that seen in MATα cells with a normal RE, displaying highly ordered nucleosomes despite the absence of Matα2. Further, a mutation that alters the ability of Mcm1 to act with Matα2 in repressing a-specific genes also alters donor preference in either mating type. Thus, Mcm1 is critically responsible for the activation as well as the Matα2-Mcm1-mediated repression of RE activity.     

Antioxidant enzyme systems in skeletal muscle atrophied by immobilization

To clarify the mechanism of oxidative stress in skeletal muscle atrophied by immobilization, we investigated the change of antioxidant enzyme activities in a typical slow red muscle, the soleus. Atrophied soleus muscles were collected from male Wistar rats (16 weeks old), one ankle joint of which had been immobilized in the fully extended position for 7 days. Also, soleus muscles were collected from intact age-matched rats as control. The activities of Mn-containing superoxide dismutase (Mn-SOD), Cu,Zn-containing superoxide dismutase (Cu,Zn-SOD), Se-dependent glutathione peroxidase (Se-GSHPx), glutathione S-transferase (GST), catalase, and glutathione reductase (GSSGRx) were measured. The activities of Cu,Zn-SOD, GST, and GSSGRx were significantly higher in atrophied muscles, while the others were unchanged. Increased Cu,Zn-SOD and unchanged Mn-SOD levels might reflect increased generation of superoxide anions in the cytoplasm rather than in the mitochondria. Owing to the enhancement of Cu,Zn-SOD and the unaltered Se-GSHPx and catalase activities, hydrogen peroxide is thought to be increased in the cytoplasm. Because there is also an increase of iron in the microsomes of atrophied muscles, the production of hydroxyl radicals, the most aggressive of radicals, might consequently be elevated.     

Evaluation of endocrine disrupting activity of plasticizers in polyvinyl chloride tubes by estrogen receptor alpha binding assay

Polyvinyl chloride (PVC) tubing is an indispensable medical material for extracorporeal circulation therapy. However, di(2-ethylhexyl)phthalate (DEHP), a suspected endocrine disruptor, can be eluted from PVC, suggesting that an alternative material that does not contain DEHP is needed for clinical applications. First, we evaluated the endocrine disrupting risks of the plasticizers contained in PVC tubes by investigating their binding affinities for the human estrogen receptor alpha (ERα). Our results revealed that, while DEHP has some binding affinity for ERα, neither epoxidized soybean oil nor tris(2-ethylhexyl)trimellitate (an alternative to DEHP) has any affinity for ERα. Second, we evaluated the endocrine disrupting risks of a tube made of newly developed plasticizer-free (PF) materials. We confirmed the presence of DEHP and detected several unidentified substances in plasma stored within the PVC tube. This plasma's competitive binding affinity for ERα was significantly higher than that of control plasma (P < 0.01). In contrast, the profile of plasma stored in the PF tube was similar to that of the control, both in terms of high-performance liquid chromatography chromatograms and competitive binding capacity for ERα, suggesting that the PF tube is biocompatible and is useful for reducing the elution of substances capable of binding to ERα. Presented in part at the 42nd Congress of the Japanese Society for Artificial Organs, October 5–7, 2004, Tokyo, Japan     

Morphological study of disordered myelination and the degeneration of nerve fibers in the spinal cord of mice lacking complex gangliosides

Gangliosides, a family of glycosphingolipids that contain sialic acid, are abundant on the neuronal cell membranes, but their precise functions in the central nervous system remain largely undefined. In a previous study of GalNAc-T(-/-) mice engineered to lack beta1,4-N-acetylgalactos-aminyltransferase (GM2/GD2 synthase) to abolish any, complex gangliosides, we observed the reduction of nerve conduction velocity but did not find any obvious morphological change in the brain. In the present study, we observed morphological changes in the nerve fiber tracts of the spinal cord in these mice. In GalNAc-T(-/-) mice, the number of degenerated axons was markedly increased in the dorsal funiculus, tract of Lissauer, and dorsolateral funiculus of the cervical segment of the spinal cord as well as the dorsal funiculus and tract of Lissauer of the lumbar segment of the spinal cord. There were also increased numbers of unmyelinated fibers in GalNAc-T(-/-) mice. Loosened myelin sheaths and myelin sheaths separated from axons by wide spaces were also observed in GalNAc-T(-/-) mice. These results provide a morphological basis for the previously observed reduction in the nerve conduction velocity and suggest that complex gangliosides are essential for the maintenance of myelin and the integrity of nerve fibers of the spinal cord.