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I Steiner

Publications and source records attributed to I Steiner.

At least 19 recordsLinked to original sources
PubMed1992

Neurologic manifestations of progressive systemic sclerosis.

Neurologic involvement in progressive systemic sclerosis is considered uncommon. We retrospectively examined the prevalence and nature of neurologic complications in 50 patients with progressive systemic sclerosis. In 20 (40%), neurologic abnormalities were detected, with a total of 28 neurologic manifestations. All levels of the central and peripheral nervous system were affected: muscle (22%), peripheral nerve (18%), spinal cord (8%), and brain (6%). Of note were the presence of myelopathy in four patients and inclusion-body myositis in two. In 10 patients (20%), no definable cause of the neurologic dysfunction could be identified, apart from progressive systemic sclerosis. Thus, neurologic presentations of progressive systemic sclerosis are much more common than previously reported and may be due to direct involvement of the nervous system by a primary pathologic process in a significant number of patients.

Adult↗
PubMed1992

Multifocal motor nerve conduction abnormalities in amyotrophic lateral sclerosis.

Motor nerve conduction in motor neuron disease is considered normal until the terminal stages of the disease, a notable exception being lower motor neuron syndrome associated with anti-glycolipid antibodies. We reviewed the electrophysiological findings in all our patients who were diagnosed as having amyotrophic lateral sclerosis (ALS) during the last 6 years. Six patients, clinically indistinguishable from "classical" ALS patients, out of 31 (19%) displayed motor nerve conduction abnormalities. The most consistent finding, occurring in all 6, was prolonged distal latency or reduced conduction velocity in the distal segment of the median nerve, with normal sensory conduction, suggesting possible pressure proneness of motor nerve fibers in ALS. Additional abnormalities included multifocal motor conduction slowing (3 patients), and conduction blocks (4 patients). None of the patients had paraproteinemia and anti-GM1 and anti-GD1a antibodies were not detected. Thus, a subgroup of clinically indistinguishable ALS patients may have multifocal motor nerve conduction abnormalities, indicating motor nerve fiber involvement. The etiology and pathogenesis of the peripheral nerve involvement are presently unknown.

Adult↗
PubMed1991

Hereditary branching enzyme dysfunction in adult polyglucosan body disease: a possible metabolic cause in two patients.

We describe 2 unrelated patients with adult polyglucosan body disease (APBD) diagnosed by sural nerve biopsy. Both patients were offspring of consanguineous marriages. They presented clinically with late onset pyramidal tetraparesis, micturition difficulties, peripheral neuropathy, and mild cognitive impairment. Magnetic resonance imaging of the brain revealed extensive white matter abnormalities in both. In search of a possible metabolic defect, we evaluated glycogen metabolism in these patients and their clinically unaffected children. Branching enzyme activity in the patients' polymorphonuclear leukocytes was about 15% of control values, whereas their children displayed values of 50 to 60%, suggesting a possible autosomal recessive mode of transmission. This is the first report of an inherited metabolic defect in patients with adult polyglucosan body disease. We suggest that branching enzyme dysfunction may be implicated in the pathogenesis of some patients with adult polyglucosan body disease.

1,4-alpha-Glucan Branching Enzyme↗
PubMed1991

[The effect of terephthalic acid and foils made of polyterephthalic acid esters on fat soluble vitamins].

The effect of terephthalic acid, which is found in foodstuffs as a monomer of fat-soluble vitamins such as vitamin A, D3 and alpha-tocopherol was examined in model tests of terephthalic acids, and of foils composed of polyterephthalic acid esters. Vitamin A and D3 were stabilized by terephthalic acid (the vitamin content was up to 25% after adding terephthalic acid, depending on temperature and duration of heating); alpha-tocopherol was reduced a little faster with terephthalic acid. Heated in the foil the vitamin content was not reduced as much as in the model tests with terephthalic acid.

Cholecalciferol↗
PubMed1991

Seronegative myasthenia gravis: clinical features, response to therapy and synthesis of acetylcholine receptor antibodies in vitro.

Circulating autoantibodies against the acetylcholine receptor (AChR-Ab) are an important diagnostic tool in myasthenia gravis (MG). Lack of antibodies may cast doubt upon the diagnosis, the immune-mediated mechanism and the nature of the antigen. We examined clinical and laboratory features, response to immunotherapy and production of AChR-Ab in vitro, in 12 seronegative MG patients who were followed up for 2-30 years. It was possible to divide those patients into 2 groups: 7 patients with systemic muscle weakness, with a severe disease and with response to immunosuppressive therapies. The other group of 5 patients was characterized by oculobulbar symptomatology, a relatively benign course and immunotherapy was ineffective in 3 treated patients. Five patients underwent thymectomy and gland histology was normal in all of them. In none of 9 patients examined, were AChR-Ab synthesized in vitro (compared to 65% of seropositive myasthenic patients). Thus seronegative generalized MG is probably an autoimmune disease though the autoantigen is presently unknown and is responsive to immunosuppressive treatment. Seronegative oculobulbar MG might represent a separate disease entity in which immunological mechanisms play no significant role.

Adolescent↗
PubMed1991

The HSV-1 latency associated transcript (LAT) variants 1704 and 1705 are glycoprotein C negative.

The latency associated transcripts (LAT) of herpes simplex virus type 1 (HSV-1) are encoded by diploid genes that are expressed during latent infections. Two LAT variant viruses, 1704 and 1705, were compared with the parental strain 17+. Variant 1705 has a deletion affecting one copy of the LAT genes, expresses LATs during latent infection and reactivates normally. Variant 1704 has deletions affecting both LAT gene copies, does not express LATs during latent infection, and its reactivation is impaired (Steiner et al., 1989). Comparison of infected cell proteins by immunoprecipitation and Western blot analysis revealed one significant difference between HSV-1 strain 17+, 1704 and 1705; glycoprotein C (gC) was not synthesized by 1704 or 1705. Since both 1704 and 1705 are gC minus, the reactivation defect of 1704 is most likely related to the absence of the LATs, and not to the absence of gC.

Animals↗
PubMed1991

Investigation of herpes simplex virus type 1 (HSV-1) gene expression and DNA synthesis during the establishment of latent infection by an HSV-1 mutant, in1814, that does not replicate in mouse trigeminal ganglia.

In previous studies, the herpes simplex virus type 1 (HSV-1) mutant, in1814, which lacks the trans-inducing function of Vmw65, did not replicate in the trigeminal ganglia of mice following corneal inoculation but did establish a reactivatable latent infection in the ganglia 12 to 24 h after ocular infection. Since in1814 did not replicate in vivo, the molecular events during the establishment phase of latent HSV-1 infection could be characterized without the complications of concurrent productive viral infection. In comparison to parental HSV-1 strain 17+, the expression of viral immediate early (IE), early and late genes and the levels of viral DNA in the trigeminal ganglia of mice following in1814 infection were greatly reduced. However, accumulation of latency-associated transcripts, a prominent feature of latent HSV-1 infection, occurred in a wild-type fashion. Furthermore, low levels of viral gene expression and an increase in the level of viral DNA in the in1814-infected ganglia were not detected until 1 to 2 days after the establishment of HSV-1 latency. Thus, IE gene expression and replication of viral DNA in the trigeminal ganglia are not prerequisites for the establishment of HSV-1 latency. These results suggest that the pathways leading to productive and latent infections in neurons may diverge at an early stage of the host-HSV-1 interaction and that the level of viral IE gene expression has a key role in determining the outcome of infection.

Animals↗
PubMed1991

Herpes simplex virus latency in the nervous system--a new model.

Permissive herpes simplex virus (HSV) infection in tissue culture results in host cell destruction. Latent HSV infection in vivo occurs in neurons of peripheral sensory ganglia (PSG) and it therefore can not take place in neurons in which the virus has completed a lytic replication cycle similar to that present in vitro. Our hypothesis, based on experimental data and observations in humans, suggests that establishment of latent infection and reactivation of HSV-1 does not involve neuronal cell loss. Latency is established in neurons in which the virus does not replicate and is determined, in part, by the tissue levels of a herpes transactivating protein (Vmw65) that is a component of the viral tegument. We also suggest that reactivation of latent infection does not involve destruction of neurons and is due to replication of virus at the peripheral mucocutaneous tissues to where virus or viral DNA have been transported from the nervous tissue. Alternatively, reactivation is initiated in the PSG using a replication cycle which does not involve irreversible damage to neurons. This model explains the lack of damage to neurons which continue to serve as permanent reservoirs of latent virus for the entire life of the host.

Animals↗
PubMed1991

In vivo and in vitro reactivation impairment of a herpes simplex virus type 1 latency-associated transcript variant in a rabbit eye model.

Many recent studies of latent herpes simplex virus type 1 (HSV-1) infections within the nervous system have focused on the diploid genes encoding the latency-associated transcripts (LATs). The impaired explant reactivation of LAT variants from mouse trigeminal ganglia has implicated the LATs in the efficiency or speed of the reactivation process (D. A. Leib, C. L. Bogard, M. Kosz-Vnenchak, K. A. Hicks, D. M. Coen, D. M. Knipe, and P. A. Schaffer, J. Virol. 63:2893-2900, 1989; I. Steiner, J. G. Spivack, R. P. Lirette, S. M. Brown, A. R. MacLean, J. H. Subak-Sharpe, and N. W. Fraser, EMBO J. 8:505-511, 1989). However, it is not known how closely explant reactivation mimics the reactivation process in vivo. In the current study, a LAT variant (1704), parental strain (17+), and rescuant (1704R) were compared in vivo for reactivation of latent infection by iontophoresis in the rabbit eye model and in vitro by explant cocultivation of trigeminal ganglia from rabbits. Following iontophoresis, 17+ and 1704R reactivated in vivo from 76 and 64% of rabbits, respectively, while 1704 reactivated only from 4% (1 of 25) of the animals. In explant reactivation experiments, 17+ and 1704R reactivated from 98 and 67% of rabbit trigeminal ganglia, while 1704 reactivated from only 28% of trigeminal ganglia. The mean time required for the appearance of reactivated 1704 in explant culture, 17 days, was significantly longer than for 17+ and 1704R, 8 to 9 days. Thus, the explant reactivation kinetics in rabbit trigeminal ganglia reflect the behavior of LAT variant 1704 in vivo in the rabbit eye model. These data support the role of the LATs in the reactivation process and support the hypothesis that explant reactivation is a suitable system for analyzing the biological behavior of HSV-1 variants with defined genetic alterations in the LAT gene.

Animals↗
PubMed1991

Acute inflammatory demyelinating polyneuropathy following bone marrow transplantation.

Acute inflammatory demyelinating polyneuropathy (AIDP) appeared in two patients following allogeneic bone marrow transplantation (BMT). In one transplanted patient (but not in the donor) T cells were sensitized against peripheral nervous system myelin. This could reflect a change in the T cell repertoire in a different milieu. In this context, AIDP might be part of graft-versus-host disease or another associated autoimmune disorder following BMT.

Adolescent↗
PubMed1991

Development of experimental allergic encephalomyelitis during steroid administration. Outcome of neurological immune-mediated disorders under immunosuppressive therapy.

Glucocorticoids are frequently employed as immunosuppressive agents. Following clinical reports of occurrence and exacerbation of neurological immune-mediated conditions in patients receiving steroids, we studied the course of experimental allergic encephalomyelitis (EAE) in rats receiving methylprednisolone prior to and during disease induction and after the appearance of clinical signs. High methylprednisolone dose given prior to EAE induction significantly increased disease duration and the number of days at maximal disability. When the drug was given prior to and during the induction phase, both moderate and high doses exacerbated the EAE course. In contrast, treatment with methylprednisolone after the onset of clinical disease had a markedly beneficial effect. Thus, time of initiation, dosage and duration of treatment may differentially affect the course of EAE. Moreover, the natural course of a neurological immune-mediated condition may be worsened when it is triggered while the patient is under steroid treatment.

Animals↗
PubMed1990

[The effect of terephthalic acid and film made from polyterephthalic acid esters on water soluble vitamins].

Terephthalic acid is used for the production of polyterephthalic acid esters for foils that are applied for cooking, roasting, and baking; it is able to migrate as a monomer into foodstuffs. The effect of sodium terephthalate on vitamins such as thiamin, riboflavin, pyridoxine, and ascorbic acid at different conditions (variation of time and temperature); effects of a foil made of polyterephthalic acid esters was also tested. Thiamin and riboflavin are stabilized by sodium terephthalate while pyridoxine is decomposed faster, especially at higher temperatures. The tests of thiamin and riboflavin in the foils show similar results, whereas the losses of pyridoxine were not so high compared with the tests where sodium terephthalate had been added. Ascorbic acid is protected, too, by sodium terephthalate, except with long heating periods at a temperature of 220 degrees C.

Ascorbic Acid↗
PubMed1990

[Chemical and microbiological studies of microwave-treated milk].

Pasteurized milk was treated with microwaves for 2.5 minutes (2450 MHz, 650 W). Important chemical components (vitamin A, beta-carotin, vitamins B1, B2, C, E; activity of peroxidase, xanthinoxidase; content of fat and peroxides, percentage of solids, content of raw protein, content of all microorganisms and storage stability were examined. Ascorbic acid (reduction of 36%) and alpha-tocopherol (reduction of 17%) were influenced by microwave treatment, whereas other chemical parameters, odor and flavor remained unchanged. The content of microorganisms was reduced from about 10(4) to 10(2) per milliliter. Untreated milk had a content of 10(7) microorganisms per milliliter after 10 days storage at 8 degrees C and a taste of acidity, whereas in milk treated with microwaves only 10(4) microorganisms per ml were identified and no organoleptic changes could be observed after 14 days storage at 8 degrees C.

Animals↗
PubMed1990

A herpes simplex virus type 1 variant, deleted in the promoter region of the latency-associated transcripts, does not produce any detectable minor RNA species during latency in the mouse trigeminal ganglion.

In peripheral sensory ganglia latently infected with herpes simplex virus type 1 (HSV-1) transcription is restricted. A set of viral latency-associated transcripts, the LATs, have been characterized by Northern blotting and in situ hybridization. These transcripts have previously been mapped to a 3 kb region of the viral genome within the repeat long region. However, transcription from adjacent regions of the genome can be detected by in situ hybridization, which cannot be detected by Northern blotting. These RNAs are termed minor LATs or m-LAT. In this study we show that in ganglia latently infected with the HSV-1 variant 1704, which is deleted in one complete copy of the LAT gene and in the promoter and 5' portion of the other copy, m-LATs are not detected by in situ hybridization. Furthermore, the levels of DNA in nervous system tissue latently infected with the parental and the 1704 variant virus are similar. Thus we propose that the sequence elements necessary for initiating transcription or stabilizing m-LATs are within the region deleted in variant 1704 that codes for the promoter and the 5' end of the LATs.

Animals↗