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M Zeidler

Publications and source records attributed to M Zeidler.

53 records · Page 3Linked to original sources
PubMed1996

A new variant of Creutzfeldt-Jakob disease in the UK.

BACKGROUND: Epidemiological surveillance of Creutzfeldt-Jakob disease (CJD) was reinstituted in the UK in 1990 to identify any changes in the occurrence of this disease after the epidemic of bovine spongiform encephalopathy (BSE) in cattle. METHODS: Case ascertainment of CJD was mostly by direct referral from neurologists and neuropathologists. Death certificates on which CJD was mentioned were also obtained. Clinical details were obtained for all referred cases, and information on potential risk factors for CJD was obtained by a standard questionnaire administered to patients' relatives. Neuropathological examination was carried out on approximately 70% of suspect cases. Epidemiological studies of CJD using similar methodology to the UK study have been carried out in France, Germany, Italy, and the Netherlands between 1993 and 1995. FINDINGS: Ten cases of CJD have been identified in the UK in recent months with a new neuropathological profile. Other consistent features that are unusual include the young age of the cases, clinical findings, and the absence of the electroencephalogram features typical for CJD. Similar cases have not been identified in other countries in the European surveillance system. INTERPRETATION: These cases appear to represent a new variant of CJD, which may be unique to the UK. This raises the possibility that they are causally linked to BSE. Although this may be the most plausible explanation for this cluster of cases, a link with BSE cannot be confirmed on the basis of this evidence alone. It is essential to obtain further information on the current and past clinical and neuropathological profiles of CJD in the UK and elsewhere.

Adolescent↗
PubMed1996

Tetracycline-regulated reporter gene expression in the moss Physcomitrella patens.

As ancestors of higher plants, mosses offer advantages as simple model organisms in studying complex processes such as development and signal transduction. Overexpression of transgenes after genetic transformation is a powerful technique in such studies. To establish a controllable expression system for this experimental approach we expressed a chimeric protein consisting of the Tn1O-encoded Tet repressor and the activation domain of Herpes simplex virion protein 16 in the moss Physcomitrella patens. We showed that this protein activates transcription from a suitable target promoter (Top 1O) containing seven operators upstream of a TATA box. In media containing very low levels of tetracycline (1 mg/l), expression levels of a beta-glucuronidase (GUS) reporter gene dropped to <1% of that in the absence of tetracycline. This regulation is due to interference of tetracycline with the DNA binding activity of the Tet repressor portion of the chimeric transcriptional activator. Stable transformants grown for three weeks on tetracycline-containing media showed negligible GUS activity, whereas GUS was expressed strongly within 24 h of transfer to tetracycline-free media. Potent and stringently regulated expression of other, physiologically active genes is thus readily available in the moss system using the convenient ToplO expression system.

Anti-Bacterial Agents↗
PubMed1996

A chloroplast transcript lacking the 3' inverted repeat is degraded by 3'-->5' exoribonuclease activity.

Chlamydomonas reinhardtii strains harboring deletions of the chloroplast atpB 3' inverted repeat (IR) are weakly phototrophic due to reduced accumulation of discrete atpB transcripts and the chloroplast ATPase beta-subunit protein. A sequence of 18 guanosine residues, which can impede a 3'-->5' exoribonuclease in vitro, is able to substitute for the atpB IR in vivo. Strains containing the poly-guanosine tract in place of the atpB 3' IR are phototrophic and accumulate near wild-type levels of discrete atpB transcripts and the ATPase beta-subunit protein. Because these atpB transcripts contain the 18 guanosine residues, and the poly-guanosine tract is not a terminator of transcription, the accumulation of discrete atpB transcripts is likely the result of impediment of 3'-->5' exoribonuclease activity. These findings support a model in which atpB transcripts lacking the 3' IR are degraded by 3'-->5' exoribonuclease activity, and demonstrate that the poly-guanosine tract can be used to study chloroplast RNA metabolism in vivo.

Adenosine Triphosphatases↗
PubMed1995

Self-reported signs and symptoms in breast implant patients with novel antibodies to silicone surface associated antigens [anti-SSAA(x)].

In research animals, the immune adjuvant activity of silicone in eliciting antibodies to associated protein antigens is now well established. In humans, the immune adjuvant activity of silicone remains controversial. Clusters of data from various research groups are beginning to define the boundary conditions for future large epidemiological studies. In that spirit, this manuscript reports pilot clinical data from a serological study conducted 3 years ago and reported previously in this journal. Sera from a self-selected symptomatic population of patients with breast implants were assayed for elevated concentrations of antibodies showing binding avidity to silicone surface associated antigens [anti-SSAA(x)]. In that study of 249 patients, two distinct statistically significant subgroups were identified on the basis of the serological assay alone: patients without any elevated anti-SSAA(x) (negative) and patients with elevated anti-SSAA(x) (positive) (p < 0.001). In this study, a clinical survey returned by 226 of those patients was correlated with the previously acquired serological findings. The 11 most common clinical complaints reported by the 199 anti-SSAA(x) negative patients and by the 27 anti-SSAA(x) positive were compared and their frequencies analyzed. The 199 anti-SSAA(x) negative patients, as a group, showed a lower frequency of a variety of signs and symptoms compared to the 27 anti-SSAA(x) positive patients. Statistically significant differences were seen in three of the symptoms: fever, foot pain, and sleep disturbance (p < 0.05). In addition, the syndrome of fever in the absence of local chest pain was a significantly associated with anti-SSAA(x) positivity (p < 0.001).

Antibodies↗
PubMed1984

Preclinical evaluation of the anti tumour activity of new epoxyde derivatives.

As a follow-up to our initial results on the antineoplastic activity of alpha-1,3,5-triglycidyl-s-triazinetrione (alpha TGT, NSC-296934, Teroxirone), many new epoxyde derivatives were tested against murine tumours, mostly against P388 leukaemia, to determine their antineoplastic role and to characterize their specific effect against tumour cells in vivo, as well as to select an analogue with higher anti-cancer properties and superior pharmacological properties. Triglycidyl urazol (TGU, NSC-332488) showed the highest therapeutic activity and a good level of water-solubility which makes this agent a good candidate for phase-one clinical trials.

Animals↗
PubMed1983

Organization and structure of branches in the rat pulmonary arterial bed.

Pulmonary arteries were fixed by perfusion under constant pressure and filled with rubber. The hardened rubber cast delineated the arterial bed, permitting dissection of axial vessels and all branches. Each segment was prepared for scanning electron microscopy and transmission electron microscopy. Branches arising at acute angles from the axial artery and the first two generations of its branches, regardless of diameter, had the same concentric muscle layer structure as parent vessels. Endothelial cells of the parent vessel were oriented into the ostia of these branches. Branches that came off the axial vessel or its branches at right angles had spiral muscle bundles and led to nonmuscular precapillary vessels. Right angle branches also had similar wall structure regardless of diameter. Near the ostia of right angle branches, endothelial cells of the parent vessels did not show orientation of their long axis into the branch lumens. It was concluded that branch arteries arising at acute angles are conduit which carry blood to distant parts of the lung while right angle branches are a histologically different group which distribute the blood to local capillary beds.

Animals↗
PubMed1983

[Results of iridectomy in narrow-angle and open-angle glaucoma. A retrospective study].

Between 1970 and 1975 166 iridectomies were performed in cases of primary glaucoma. In the retrospective study reported here the authors analyzed the results with regard to the regulation of intraocular pressure (IOP) and loss of function. Follow-up examinations were performed (1) between 6 weeks and 6 months, (2) 12 months, (3) 1.5 to 2.5 years and (4) 3 to 4 years after surgery in patients whose IOP was not adequately regulated. Hypotonia was rare. Of the eyes with acute narrow-angle glaucoma with an open iridocorneal angle by definition, which underwent surgery for the first time, 30% had an IOP of more than 21 mm Hg with or without additional tension-lowering medication (20% between 22 and 24 mm Hg, 10% over 24 mm Hg). The results for eyes operated on for the second time were better because of the prophylactic iridectomies in this group. In one-third of the cases the iridocorneal angle was occluded; in two-thirds an open angle was found. An analysis revealed that regulation was better when the previous tension level had been high, while lower tension levels, of between 20 and 35 mm Hg, often remained elevated after surgery. Out of the total number of eyes operated on for the first time (narrow-angle and open-angle glaucoma) IOP was regulated by iridectomy alone in 54% after 1 year and in 33% after 2 years. With regard to the iridocorneal angle of these 33%, it was found that 50% of the cases of narrow-angle glaucoma were regulated without further medication, but only 20% of the open-angle cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗