Neurologic disorder of vitamin E deficiency in acquired intestinal malabsorption

Fifteen years after onset of a malabsorption syndrome, a 49-year-old man had sensory and oculomotor disorder with marked vitamin E deficiency. After 6 months of treatment with high parenteral doses of vitamin E, the neurologic signs slowly receded, but the patient died of gastrointestinal hemorrhage. Autopsy and sural nerve biopsy showed the changes in both central and peripheral nerves; these changes are considered characteristic of vitamin E deficiency.

[Immunopathogenesis of polyneuropathies in paraproteinemia]

Polyneuropathies are the most common neurological complications of paraproteinemias . In many cases pathogenesis remains unclear. In two patients with chronic demyelinating neuropathy in IgM-paraproteinaemia subtle methods were applied ( immunoelectroblot and immunocytochemistry). It could be demonstrated that the pathologic antibodies in the patients' serum reacted specifically with an antigen in the sheath, the myelin-associated glycoprotein. These observations suggest an antibody-mediated immunopathogenesis of the patients' polyneuropathy and invite prospects for a rational treatment with immunosuppressive approaches.

Nemaline myopathy appearing in adults as cardiomyopathy. A clinicopathologic study

We examined a 29-year-old woman with nemaline myopathy that appeared as cardiomyopathy. Clinical examination showed dilated cardiomyopathy, but no neuromuscular abnormalities of the skeletal muscles. Electromyography showed neither neurogenic nor myopathic abnormalities. A biopsy specimen from the quadripecs muscle showed typical nemaline bodies in about 50% of the muscle fibers. The patient died six months later of biventricular heart insufficiency. Autopsy revealed nemaline bodies in the working and conducting tissues of the myocardium. Earlier, the patient's mother and one of her sisters died unexplained, sudden deaths at the ages of 47 and 37 years, respectively. Sections of the myocardium taken from the sister at autopsy were available, and also disclosed nemaline bodies after restaining with trichrome.

Demyelinating polyneuropathy associated with monoclonal IgM-paraproteinaemia. Histological, ultrastructural and immunocytochemical studies

Histological, ultrastructural and immunocytochemical findings of sural nerve biopsies from 2 patients with monoclonal IgM-paraproteinaemia are presented. In both cases the pathological IgM antibodies reacted with a myelin antigen which was identified as myelin-associated glycoprotein (MAG) by immunoelectroblot . Histology and electron microscopy showed typical features of a chronic demyelinating neuropathy with accompanying axonal degeneration. Immunohistochemical studies demonstrated IgM in the vicinity of endoneurial vessels and on some of the myelinated fibres. The localisation of IgM on the myelin sheath showed a typical pattern, which was similar to that found in binding studies with the patients sera on control nerves. It resembled the characteristic immunocytochemical staining pattern of MAG. Binding studies with the patients' sera on human and canine CNS material exhibited a clear labelling of white matter and certain, as yet unidentified structures within the cerebral and cerebellar cortex. In mixed glial cell cultures, the sera of both patients bound specifically to oligodendrocytes. Our observations are interpreted as immunohistochemical evidence that the anti-MAG antibodies of the patients' sera had bound to their antigenic target in the peripheral nerves. Because the antibodies clearly react to central myelin, oligodendrocytes and other not yet identified cortical structures, CNS involvement in such disorders should be considered.

Tetrodotoxin-resistant release of 3H-noradrenaline from the mouse vas deferens by high intensity electrical stimulation

Vasa deferentia of mice were preincubated with 3H-noradrenaline and then superfused with a medium containing cocaine 10 microM and phentolamine 30 microM. The tetrodotoxin-resistant outflow of tritium evoked by high intensity electrical field stimulation (0.5 Hz, 200 mA current strength, 2 ms pulse width) was studied and, in some experiments, compared with the tetrodotoxin-sensitive outflow evoked by low intensity electrical field stimulation (0.5 Hz, 50 mA, 1 ms). In contrast to the outflow evoked by low intensity stimulation, the outflow evoked by high intensity stimulation was increased in Na+-free medium, and was only partly dependent on the external Ca2+ concentration. The Ca2+-dependent fraction consisted mainly of 3H-noradrenaline. Again, in contrast to the outflow caused by stimulation at low intensity, that caused by stimulation at high intensity was not reduced by Mg2+ 20 mM, Co2+ 5 mM or normorphine 40 or 100 microM, and was not enhanced by tetraethylammonium 5 mM or 4-aminopyridine 1 mM. It is concluded that high intensity electrical stimulation elicits a tetrodotoxin-resistant, calcium-dependent release of noradrenaline which differs in mechanism from the release elicited by action potentials.

Polyneuropathy in Waldenström's macroglobulinaemia: reduction of endoneurial IgM-deposits after treatment with chlorambucil and plasmapheresis

A case of progressive polyneuropathy associated with Waldenström's macroglobulinaemia is reported. A monoclonal IgM-lambda gradient was detected in the serum and cerebro-spinal fluid. By electro-immunoblot analysis antibodies against myelin-associated glycoprotein were found in the serum and cerebro-spinal fluid. The motor and sensory conduction velocities of several peripheral nerves were markedly decreased, and examination of visual evoked potentials (VEPs) revealed pathological latencies. Sural nerve biopsies before and after treatment with chlorambucil and plasmapheresis showed nerve fibre loss and demyelination. In the pre-treatment biopsy, heavy accumulations of filamentous material were found which stained positively for IgM by immuno-cytochemistry. Such accumulations had disappeared in a biopsy performed after treatment. The morphological findings were correlated with an improvement of clinical and electro-physiological findings.

[Long-term EEG course study in patients with Creutzfeldt-Jacob disease]

In a patient with Creutzfeldt-Jakob disease subsequently confirmed by autopsy, 34 EEGs were carried out in a 14 months period. 6 weeks after the beginning of the prodromal stage of the disease a triphasic, periodic activity was recorded for the first time. This activity was maximally in evidence at 15th week. A synchrony occurring between repetitive complexes and myoclonic jerks could between repetitive complexes and myoclonic jerks could only be observed during one recording. From the 5th month onwards the intensity of the periodic EEG pattern, seen longitudinally, gradually decreased. In the time-span from the 10th to the 13th month considerable fluctuations of periodic activity were found, this during the course of one as well as between different EEG recordings. These could reach from a pronounced typical pattern to complete disappearance of periodic triphasic complexes. As possible causes for these fluctuations, we discussed a variable driving by the subcortical pacemaker as well as a decreased capability of cerebral cortex--gradually loosing so many neurons--to react to subcortical stimuli. From the 14th month onwards the periodic activity no longer could be put in evidence. In the last EEG recorded 3 days before death isoelectric periods alternated with paroxysmal delta waves respectively sharp and slow wave complexes.

Hereditary motor sensory neuropathies in childhood

Clinical data on 24 patients with hereditary motor sensory neuropathies, with onset in the paediatric period, and of their relatives, is reported. Electrophysiological studies were done in all patients and in 15 relatives. The patients were divided into two groups (Types I and II) and their hereditary trait was determined. In 11 patients a sural nerve biopsy was performed and revealed different patterns of histological alterations. The nerve biopsy always confirmed the value of conduction velocity in distinguishing between Types I and II. A genetic discordance was observed, both in regard to the phenotype and the conduction velocity, and there was increased slowing of the conduction velocity as individuals grew older. Thus the classification of these disorders in childhood can be particularly difficult. The rôle of sural nerve biopsy is discussed.

The central-peripheral transition zone of cervical spinal nerve roots in Jimpy mutant and normal mice. Light- and electron-microscopic study

Comparative morphological and ultrastructural investigations on the cervical dorsal and ventral central-peripheral transition zones (CPTZs) of Jimpys and control mice have been performed at early and advanced myelination stages. After postnatal development a characteristic cone-shaped glial outgrowth extends into the proximal part of the dorsal roots, while the ventral roots exhibit short Schwann cell and peripheral nervous tissue invaginations into the spinal cord at the ventral root-spinal cord junction in both animal groups. In Jimpys, although there is marked central myelin deficiency and absence of oligodendroglial development on the CNS side, the normal general aspect of the CPTZs is maintained. Previously postulated astrocytic and neuroaxonal abnormalities in the mutants do not alter the central-peripheral borderline, and Schwann cell migration from the spinal nerve roots into the cord does not occur.

Demyelinating neuropathy and monoclonal IgM antibody to myelin-associated glycoprotein

We studied a patient with demyelinating neuropathy and monoclonal IgM kappa antibody to the major myelin-associated glycoprotein (MAG). Binding of this monoclonal antibody to the myelin antigen was demonstrated by immunoelectroblot. Binding to MAG seemed to be specific, because it was completely inhibited by MAG isolated from human myelin. Immunostaining was observed with MAG from CNS and peripheral nervous system myelin.

Hereditary neuropathy with liability to pressure palsies. Report of two families and review of the literature

Clinical, neurophysiological and pathological investigations were carried out in 11 affected members of 2 families with hereditary neuropathy with liability to pressure palsies (HNPP). The observations were related to findings in 261 cases of 47 families published in the literature. It was concluded that HNPP is a nosological entity characterized by the following diagnostic criteria: (1) an autosomal dominant inheritance; (2) the clinical presentation of a recurrent mononeuropathy simplex or multiplex, frequently related to an inadequate trauma to peripheral nerves; (3) a significant slowing of motor and sensory conduction velocity in clinically affected, but also in clinically unaffected nerves; (4) characteristic morphological findings in sural nerve biopsy featuring "tomaculous" swellings of myelin sheaths, transnodal myelination and segmental demyelination. The pathogenesis of HNPP is not clear. Hypothetical explanations of the pathogenesis of HNPP are discussed.

Electrotonic depolarization of nerve terminals causes a normorphine-resistant release of transmitter

In the presence of tetrodotoxin (0.5 microM) electrical stimuli of high current strength and long impulse duration evoke the outflow of previously incorporated 3H-noradrenaline from the mouse vas deferens. The mechanism of action is probably an electrotonic depolarization of nerve terminals. The effect of normorphine, calcium and magnesium was compared on transmitter outflow evoked by conducted action potentials and electrotonic depolarization of nerve terminals. It is suggested that in the presence of tetrodotoxin electrical stimulation induces an asynchronous quantal release of transmitter.

Non-competitive interaction between normorphine and calcium on the release of noradrenaline

The interaction between calcium and magnesium or normorphine was studied on the electrically evoked outflow of previously incorporated [3H]noradrenaline in the isolated mouse vas deferens. The stimulation-evoked outflow of [3H]noradrenaline increased with increasing concentrations of Ca2+ ions in the medium. Mg2+ counteracted the effect of Ca2+ in a manner compatible with competitive antagonism. In contrast, normorphine interfered with the effect of Ca2+ non-competitively, thus suggesting that its mode of action differed from that of Mg2+.

[Hereditary motor sensory neuropathies]

The descriptive term "hereditary motor sensory neuropathy (HMSN)" includes a group of disorders of different nosology which besides heredity show a progressive distal symmetrical motor sensory neuropathy as a common clinical feature. The etiology of these disorders is probably different. According to electrophysiological and morphological findings two major types of HMSN can be distinguished from each other: 1. The neural type (HMSN, type I) is characterized by axonal degeneration, segmental demyelination and hypertrophic changes. The nerve conduction velocity in this type is significantly slowed. 2. The neuronal type (HMSN, type II) shows axonal degeneration with secondary segmental demyelination and no hypertrophic nerve changes. The nerve conduction velocity in these cases is normal or insignificantly decreased. This paper includes a historical review and a detailed description of the clinical, electrophysiological and morphological findings of the two major types of HMSN. The current classifications of HMSN are cited and critically discussed.

Peripheral and central conduction times in hereditary pressure-sensitive neuropathy

Seven members of a family with histologically proven hereditary pressure-sensitive neuropathy (HPSN) agreed to be examine clinically and electrophysiologically. A sural nerve biopsy specimen taken from the propositus who suffered from a partial brachial plexus palsy showed typical 'sausage-like' myelin sheath thickenings reflecting a failure of axon-adjusted myelination. Reduced motor and sensory conduction velocities involving several nerves were found in the four family members with clinical signs of HPSN. In addition, central conduction times in the auditory and somatosensory pathways were determined measuring the interwave latency I-V in brainstem auditory-evoked potentials and the interpeak latency N14-N20 in median nerve sensory-evoked potentials. Central conduction times in both afferent systems were within normal limits. The absolute delay of peak N14 and N20 in median and P40 in tibial nerve-evoked potentials was probably due to an impaired conduction in the peripheral branch of the bipolar ganglion cell. Whether the central axon branch in the dorsal columns was also involved could not be decided.

[Measurement of systolic time intervals by echocardiographic and conventional methods (author's transl)]

In 25 patients the systolic time intervals were simultaneously measured by echocardiography and by the conventional method using the ECG, phonocardiogram and indirect carotid pulse tracing. Beat-to-beat-analysis showed no significant difference for QS2 (367.1 +/- 26.7 ms vs. 367.9 +/- 26.5 ms). In contrast, the LVET measured by echocardiography was significantly longer than the LVET taken from the indirect carotid pulse tracing (275.3 +/- 26.3 ms vs. 266.2 +/- 25.9 ms, p less than 0.001). As a consequence, the echocardiographic PEP was significantly shorter than the conventionally measured PEP (91.3 +/- 18.0 ms vs 100.9 +/- 22.7 ms, p less than 0.001). Furthermore, both methods showed the weakest correlation for the ratio PEP/LVET. We conclude that STI can be reproducibly measured by echocardiography, which will lead to significantly different values for the STI compared to those measured by the conventional method.

Neuromyopathy and vitamin E deficiency in man

A 12-year-old boy, born of a consanguineous marriage, had ataxia, sensory neuropathy, generalized muscle hypotrophy and a lower serum vitamin E level. Two of his relatives had died of a clinically similar disorder in their late adolescence. Morphologically, his striated muscle fibers and Schwann cells of his sural nerve contained numerous autofluorescent acid phosphatase-positive lipopigments which, by electron microscopy, consisted of a finely granular matrix surrounded by a trilaminar membrane. These lysosomal lipopigments were similar to those observed in muscle fibers of a patient afflicted with abeta-lipoproteinemia. They probably represent the morphological sequelae of long-standing vitamin E deficiency in this child, the extract origin of which has not been fully elucidated.

Quantitation of DNase I sensitivity in Xenopus chromatin containing active and inactive globin, albumin and vitellogenin genes

The disappearance of defined restriction fragments of the beta 1-globin, an albumin and the A1 vitellogenin gene was quantitated after DNase I digestion and expressed by a sensitivity factor defined by a mathematical model. Analysis of naked DNA showed that the gene fragments have similar but not identical sensitivity factors. DNase I digestion of chromatin revealed for the same gene fragments sensitivity factors differing over a much wilder range. This is correlated to the activity of the genes analyzed: the beta 1-globin gene fragment is more sensitive to DNase I in chromatin of erythrocytes compared to hepatocytes whereas the albumin gene fragment is more sensitive to DNase I in chromatin of hepatocytes. The A1 vitellogenin gene has the same DNase I sensitivity in both cell types. Comparing the DNase I sensitivity of the three genes in their inactive state we suggest that different chromatin conformations may exist for inactive genes.

Multiple sclerosis and canine distemper encephalitis--an epidemiological approach

The evolution of the incidence of canine distemper encephalitis in dogs in some areas of Switzerland over the past 30 years was studied from the neuropathological records of the School of Veterinary Medicine at Berne and compared with the incidence of multiple sclerosis, as estimated from the clinical records of the Neurologic Hospital at the same University. Even considering incubation times of up to 10 years no epidemiological relationship was found between the diseases. Whereas canine distemper encephalitis has become a rare disease since the second half of the sixties, the multiple sclerosis rate has remained approximately the same. In view of these findings, a causal link between canine distemper infection in dogs and multiple sclerosis in man seems unlikely.

Prenatal mucopolysaccharidosis II (Hunter): a pathogenetic study

A prenatal diagnosis of Mucopolysaccharidosis II (M. Hunter) was made early in a pregnancy at risk in a family with one affected child. An affected fetus was diagnosed on the basis of an abnormal incorporation and degradation of 35SO4 in 35SO4-labeled mucopolysaccharides in cultured amniotic cells. Dermatan sulfate and heparin sulfate concentrations in the supernatant of the amniotic fluid were high. In the aborted fetus, the diagnosis could be confirmed by 35SO4 incorporation studies in the cultured fibroblasts and in cultured brain cells as well as by the deficiency of the specific enzyme activity (iduronide sulfate sulfatase) in the organs of the fetus. beta-Galactosidase was in the low normal range in liver and spleen but significantly reduced in brain. Under electron microscopy, the mesenchymal cells of liver and spleen showed lysosomal storage of material, presumably mucopolysaccharides, in excess of normal. In the neurons of the spinal ganglia and spinal cord, "Zebra bodies" in statu nascendi were observed.

[Comparative in vivo wear-resistance measurements between amalgam and composite materials. Results after 2 years]

The wear resistance of three different types of restorative materials for posterior teeth was examined in a 2-year clinical study. Reduction in vertical dimension was measured with the aid of profilometric grafical curves of the restoration occlusal relief. The following results were obtained: (formula: see text). The results show that, relative to wear resistance, the composite restorative material, strengthened with a new type of anorganic microfiller, is clearly superior to the conventional composite, however, is not equal to amalgam. Besides resistance to wear, there are numerous other demands of a posterior tooth composite system which have yet to be met before these microfiller composites can be recommended for the restoration of conventionally prepared Class I and II cavities.

Occurrence of lymphocytes in the cortical neuropil in a case of Creutzfeldt-Jakob disease

A 51-year-old woman suffering from visual disturbances, ataxia, spasticity, myoclonic jerks, and mental disturbances died completely demented after a 4-month course of the disease. The EEG showed typical diffuse triphasic sharp and slow-wave complexes. Histopathologic studies displaying spongiform changes in the gray matter, neuronal loss, and atrogliosis confirmed the clinical diagnosis of Creutzfeldt-Jakob disease. Electron-microscopic investigations revealed the occurrence of lymphocytes in the cortical neuropil.

Gingival blood circulation after experimental wounds in man

Capillary blood circulation following experimental wounding was observed by fluorescein angiography. Contralateral punch wounds 1.5 mm in diameter were made in healthy mandibular labial attached gingiva of 31 volunteers. Areas of ischemia were clearly visible angiographically 6 hours after wounding and were significantly greater in area (P less than 0.05) and wider (P less than 0.01) for wounds in the long axis of mandibular incisors (N = 14) than those on the vertical midline of the gingival papillae (N = 17). The ischemic changes occurred exclusively cranial to the experimental wounds. By the third day the epithelium adjacent to the wound margin in the central part of the ischemic area had necrotized, thus extending the wound coronally. By the seventh day the axial wounds were significantly (P less than 0.001) larger than the papillary wounds. The data strongly suggest that the blood supply of mandibular labial attached gingiva is preferentially oriented in an apico-coronal direction and that the capacity for collateral circulation is dependent upon local differences in vascular structure. The findings are applicable to flap design in periodontal surgery.

Morphological observations in the nervous system of prenatal mucopolysaccharidosis II (M. Hunter)

Light and electron microscopic finding in the nervous system of a 23-week-old fetus are reported, in which MPS II was diagnosed prenatally. The degrees of myelination and neuronal differentiation were similar as in a normal fetus of the same age. A storage of mucopolysaccharides in typical vacuolar inclusion bodies was present throughout the peripheral and central nervous system, mainly in cells of mesenchymal origin. "Zebra" bodies and granulo-membranous bodies, which are thought to represent secondard ganglioside accumulation were only found in the well developed neurons of the spinal cord and spinal ganglia, but not in the poorly developed neurons of the cerebellar and cerebral cortex. Mucopolysaccharide storage in endothelial cells of cerebral bood vessels precedes the appearance of lipid storgae in cerebral neurons.

[Periodontal treatment requirements, motivation and information levels in a groups of 35-year-old Zurich residents]

A representative sample of 35-year old residents of Zurich was examined with the PTN-system to determine their periodontal treatment needs. 8.8% required no periodontal treatment. An additional 7.0% required only oral hygiene instruction and motivation to restore their gingival health. 37.1% of the sample needed removal of marginal irritants. 47.1% of the sample population had periodontal pockets in two or more quadrants, in need of surgical treatment (curettage, flap surgery). Responses to a questionnaire completed by all participants in the study revealed a strong desire on their part to retain their teeth. However, knowledge of periodontal prophylactic measures and individual oral hygiene was inadequate.

[The effect of vascular injuries on the healing of experimental gingival wounds]

Following experimental infliction of stab wounds, the blood circulation in mandibular gingiva attached to the labium was studied in 31 subjects with fluorescence angiography. Ischemic circulatory disturbances six hours after infliction of the wound and enlargement of the wound three days post operationem were all directed cranially. Blood flow in this area of the gingiva seems to have a strictly caudocranial orientation; the ability to develop collateral circulation is also limited. Ischemia was significantly increased in the stab wounds set axially over the roots of the incisors. Three and seven days later, the wound surface was considerably larger than that of papillar wounds inflicted at the same level. The attached gingiva appears to be more susceptible to injury over the roots of the lower incisors than in the neighboring papillary regions.

[Composites versus amalgam: comparative measurements of abrasion resistance in vivo: 1-year results]

A method for the in-vivo measurement of wear resistance of restorative materials is described. A profilometer is used to record the reduction in vertical dimension of the test material's occlusal surface. This loss of substance is calculated as the wear resistance index. The technique was used in a 13 month clinical evaluation of 3 different restorative materials, Adaptic, Amalgam (Dispersalloy) and Estic microfill. The procedure is simple in execution and very accurate. Statistical analysis has shown significant differences in wear resistance of the examined materials independent of patient variation. Attrition and abrasion were definitely greater with a standard composite material (Adaptic) than with amalgam and a test composite (Estic microfill). The newly developed composite material utilizing extremely fine filler particles of pyrogenic SiO2 (Estic microfill) was shown to be comparable to amalgam in wear resistance during the 13-month test period.

Neuromyopathy during chronic amiodarone treatment. A case report

Clinical, electrophysiological, and the nerve and muscle biopsy findings from a case treated with amiodarone are reported. Marked distal motor and sensory impairment and distal muscular atrophy were observed clinically. The electrophysiological examination revealed normal motor and sensory conduction velocities in the median nerve; the sensory action potentials were polyphasic and reduced in amplitude. Electromyography revealed denervation potentials and severe loss of motor units in the M. extensor digitorum brevis and in the M. tibialis anterior. The light and electronmicroscopical study of a N. suralis biopsy displayed total loss of large myelinated fibers and an almost total reduction of small myelinated fibers. The number of unmyelinated axons was markedly reduced. Fibrocytes and degenerative axons polymorphous inclusion bodies were present in Schwann cells. The muscle biopsy revealed both neurogenic and myopathic changes. Lipid storage was also present in the muscle fibers. Physical and chemical analysis of the nerve and muscle biopsy revealed the content of iodine to be more than 40 times increased. The findings indicate damage of axons, schwann cells and muscle fibers. It is suggested that the lipid storage in nerve and muscle tissue might be related to the accumulation of the drug or its metabolites.

[Prospects for success in systematic periodontal treatments--a review of the literature]

Several short- and long-term studies were reviewed to determine which factors favored successful treatment of periodontal disease. Most of the surgical techniques reduced pocket depth. The modified Widman flap proved to be most favourable for maintenance and regeneration of supporting periodontal tissue in several studies when combined with optimal plaque control (home care) and frequent professional prophylaxis. Supervised oral hygiene measure are decisive in preventing periodontal disease.

[Abrasion measurements in vivo in occlusal composite and amalgam fillings]

A new method for quantitative measurement of occlusal wear on restorations is described. In a clinical evaluation with four different composites and an amalgam the method proved to be simple in execution and very exact. Statistical analysis after 7 months has shown significant differences in wear resistance of the different materials. The nature of the resulting wear was electron optically examined. Typical structural surface characteristics were observed for each of the different materials. More recently developed composities utilizing extremly small filler particles (Aerosil) seem to be comparable to amalgam in wear resistance.

[Qualitative and quantitative investigations of the skin nerves of patients with psoriasis light- and electronmicroscopical study (author's transl)]

This study was aimed at investigating the role of the nerves in the pathomechanism of psoriasis. The structure of skin nerves of 10 patients with active psoriasis and of 6 healthy control persons has been studied by means of the microscope and the electron-microscope. Eight of the patients were subjected to punch biopsies of psoritatic plaques as well as clinically normal skin. No qualitative difference could be detected between the skin nerves from psoriatic patients and from healthy persons. Quantitative investigations showed that the density of myelinated and unmyelinated axons in psoriatic skin nerves did not differ from that in normal skin nerves in a statistically significant degree. This means that the ratio of myelinated to unmyelinated axons was alike in both normal and psoriatic skin nerves. Also the diameter distribution of myelinated and unmyelinated axons was similar. The difference in the degree of myelinisation and in the myelinperiodicity between psoriatic and control skin was not statistically significant. Neither qualitative nor quantitative morphologic alterations in the skin nerves of psoriatic persons could be detected.

Glial outgrowth and central-type myelination of regenerating axons in spinal nerve roots following transection and suture: light and electron microscopic study in the pig

Glial bundles growing out of the spinal cord were observed in spinal nerve roots in the pig after their section and surgical repair. The heterotopic occurrence of glial cells, most of which were identified as astrocytes, was more frequent and more pronounced in dorsal than in ventral roots. Several of the glial bundles contained regenerated myelinated axons. These were probably myelinated by cells which showed the typical cytological criteria for oligodendrocytes and the mode of myelination was clearly of central type. It was concluded that the glial outgrowth is induced by degeneration and regeneration of axons passing the central-peripheral transition zone.

[The mouse mutant "Jimpy". Animal model of leukodystrophy]

The Jimpy mouse is an x-linked recessive mutation of the house mouse resulting a myelin deficiency in the central nervous system. It is of interest as an animal model of human leukodystrophy. Clinical symptoms include ataxia and tremor as initial signs, followed by tonic-clonic convulsions prefinally. The myelin deficiency is probably caused by a developmental disturbance of the oligodendrogial cell line. Clinical and pathological findings in the mouse mutant Jimpy show some remarkable similarities to Pelizaeus-Merzbacher disease.

[Surface analysis of 2 composite filling materials after various methods of finishing and sealing]

The surface quality of 2 composite filling materials (Adaptic with coarse hard quartz fillers and Cosmic with fine softer glass fillers) was evaluated using profilometry, scanning electron microscopy and light reflectometry after finishing with experimental diamond discs, 3M discs, corundum discs, polishing paste and also after sealing. Plaque formation on standardized surfaces of both composites was photographically recorded in 20 subjects. The sealed surfaces and the surfaces finished by the matrix alone were approximately 10 times less rough than after finishing procedures. Under in vivo conditions they reflected the most light, for both composites. The sealer failed to cover the whole composite surface. The unfinished and sealed surfaces lost their shine 3-7 days after placement in the mouth. Decrease in reflectance was independent of mechanical oral hygiene procedures. There were no significant differences in the roughness produced by the various discs on Adaptic surfaces. Diamond discs with particle size 1-3 micrometer resulted in least surface roughness and were the only instruments not destroying the filler particles of either composite. 3M discs and the rough corundum discs caused significantly more surface roughness of the Cosmic surface. Reflectometry showed that the finishing methods unfavourably affected composite surface smoothness. Among all finishing methods polishing paste produced the highest reflection value on the Cosmic surface. Adaptic surfaces were always associated with more plaque formation than Cosmic surface after all finishing methods.