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M Wenzel

Publications and source records attributed to M Wenzel.

At least 91 records · Page 5Linked to original sources

Cellular invasion on the surface of intraocular lenses. In vivo cytological observations following lens implantation.

Cellular growth on intraocular lenses can be observed by using a specular microscope. We examined in vivo the cellular pattern on the surface of implanted lenses during the early postoperative period in 63 patients. In every case inflammatory cells were noted on the lens surface at some point during the observation period. These often showed a spindle-like appearance resembling fibroblasts. The density of the cell population increased during the following days but usually did not exceed 100 cells/mm2. From the end of the first week, multinucleated giant cells may appear. In one case, a patient with a severe postoperative iritis and hypopyon demonstrated an extremely pronounced and long-lasting cellular proliferation.

Cataract Extraction↗

[Ferrocene, ruthenocene and rhodocene analogs in haloperidol synthesis and organ distribution after labeling with 103Ru and 103mRh].

Ferrocene-Haloperidol was synthesized by N-alkylation of 4-(4'-chlorophenyl)- 4-hydroxypiperidine with 1-ferrocenyl-4-chlor-butan-1-on. By heating the ferrocene-haloperidol with 103RuCl3 the 103Ru-labelled ruthenocene-haloperidol was obtained. This compound showed a high affinity for lung but not for brain in rats and mice. The decay of the 103Ru labelled compound results in the formation of the 103mRh labelled rhodocene-haloperidol, which is rapidly oxidized by air to the corresponding rhodocinium-haloperidol. This compound can be separated by extraction and TLC.

Animals↗

[A classification of intraocular bacteriologic findings following lens implantation].

Findings in seven patients with intraoperative bacterial invasions are reported. These invasions were classified in three stages of severity: (1) According to the literature it may be assumed that clinically undetectable invasion occurs in more than 10% of all operations. The bacteria detected in one case may have been a secondary finding in an electron-microscopic study. (2) A benign endophthalmitis caused by Staphylococcus epidermidis was found in three patients. The symptoms initially prompted the incorrect diagnosis "toxic lens syndrome". Cells resembling leukocytes were detected on the lenses by light microscopy. Following explantation of the lens and the posterior capsule, patients' vision slowly recovered to an average of 0.8. (3) Of three patients with fulminant panophthalmitis caused by Enterococci and/or Staphylococcus epidermidis, only one patient re-attained 0.5 vision, after two weeks; in the second case vision remained restricted to "hand movements", and in the third the eye had to be enucleated.

Aged↗

[The effect of methionine enkephalin, leucine enkephalin and the hexapeptide, dalargin on the morphology of cultured neurons].

Cell cultures derived from brain, ganglion trigeminale or retina of 5- and 9-day-old chick embryos and from brain stem or hippocampus of 16-18 day-old fetal rats were treated with Met5-, Leu5-enkephalin, or Dalargin--a synthetic hexapeptide structurally related to Leu5-enkephalin--and evaluated morphologically. The treatment of the nervous tissue cultures with the peptides markedly affected their growth pattern. Aggregates of glial and neuronal cells were surrounded by flat cells forming monolayer network structures. In cultures of brain from 5 day-old chick embryos the proliferation of the cells was significantly stimulated. No growth of neurites was observed. It is discussed that the tested Enkephalins and in the same way the Dalargin may play an important role in the early neuronal development. Their activity in phase 0 and phase 1 of the life history of nerve cells indicates aspects of temporary peptide influences. Excess of glial cells caused by the tested peptides did not enhance neuronal differentiation. The transdifferentiation of developing receptor cells into ependymal cells during the adaptation process in retina cultures as a special effect of Dalargin is discussed. The present findings suggest that the influence of (opioid) peptides in vitro may be detected morphologically and that nervous tissue culture is a valuable tool for differentiating neuronotrophic neurite-promoting and neurotoxic drug effects.

Animals↗

Scanning electron microscopical observations on telencephalon explants cultivated in vitro.

Telencephalon explants from 10 or 12 days old chicken embryos were cultivated 2 days in vitro and investigated by SEM. Already at that day, nerve fibres forming thick fasciculi were observed in the outgrowth region of the explant. Neuritic growth cones of the filiforme, or lamellipodiale type were demonstrated as well as button-like dendritic growth cones. The cell somata of bipolar or multipolar neuroblasts and pyramidal neurons could be distinguished from those of astrocytes. Some nerve fibres establish axosomatic or axodendritic contacts, basket-like arrangements of axon terminals around small neuroblasts were found.

Animals↗

[Separation of [Rh-103m]-rhodocene derivatives from the parent [103Ru]ruthenocene derivatives and their organ distribution].

The radioactive decay of [103Ru]ruthenocene derivatives leads to 103mRh labelled rhodocinium derivatives, which can be separated by the extraction of a lipophilic solution of the ruthenocen derivate with water. The separation factor 103mRh/103Ru reaches values of 32:1 Rh3+ ions are not liberated and extracted. The organ distribution of the 103mRh labelled rhodocinium derivatives gained from ruthenocene and from N-isopropyl-ruthenocene amphetamine is different from the distribution of the parent ruthenocene compound. The liver and kidney uptake of the rhodocinium-amphetamine is much higher than the uptake with ruthenocene amphetamine.

Animals↗

[Biomicroscopy of an intraocular lens. Comparison of specular microscopy findings with the cytologic specimen].

Seventeen months after implanting an anterior chamber intraocular lens the lens had to be removed because of secondary glaucoma and retinal hemorrhage. The lens had been examined 5 days prior to surgery. It appeared that histiocytic giant cells and fibroblasts had settled on its surface. This was subsequently confirmed by cytological studies. It therefore appears possible to describe an in vivo differential cytology and to diagnose the type of inflammatory reaction in vivo.

Aged↗

[Cells on intraocular lenses. Comparison of specular and slit-lamp microscopy findings].

Examination with a specular microscope facilitates diagnostic evaluation of cells on the surface of intraocular lenses. Similarly, slit-lamp examination makes specular microscopic studies possible. However, image resolution and magnification are not achieved by using this method, though the amount of time and instrumental effort is minimal. Various types of cells can be differentiated. Fibroblast-like cells can only be demonstrated readily in the specular areas, whereas multinucleate giant cells can usually also be seen by using focal illumination. It is difficult to differentiate the smaller, mononucleated cells.

Fibrin↗

[Effects of cyclic adenosine-3',5'-monophosphate and cyclo(Lys-Pro).HCl neuronotrophic factors in tissue culture].

Explants and cell cultures of embryonic chick ganglia trigeminalia, telencephalon and retina or hippocampus from fetal rats were incubated in maximow chambers in the presence of cyclic AMP and the dipeptide cyclo(Lys-Pro).HCL under various conditions. Maintenance of nerve cells and growth of nerve fibers were observed by morphometrical methods. 1. Cyclo(Lys-Pro).HCL promoted the maintenance of neuroblasts and the growth of nerve fibres in explants of the ganglion trigeminal and retinal cell cultures. The effect depended on the presence of serum in the medium by use of poly-I-lysine substrate. 2. Extern applicated cyclic AMP and the dipeptide SP3-4 = cyclo(Lys-Pro).HCL facilitated neurite growth in PNS cultures. In the presence of the drugs the length of nerve fibers increased for a short term. On CNS explants substance P (SP1-11) and SP3-4 were without effect. Cyclic AMP stimulated the growth of nerve fibers in CNS explants and cell cultures in number and length. 3. Discussed is the effect of SP1-11 and cyclo(Lys-Pro).HCL for competence of nerve fibre regeneration in vitro in relation to increasing cAMP levels, which may then act as an initial second messenger. It is suggested that explants and cell cultures of nervous tissues will be useful as a tool for the further characterisation of factors with neuronotrophic activities.

Animals↗

Scanning electron microscopical observations on retina cells in culture.

In cell cultures of the retina from 10 days old chicken embryo photoreceptors, bipolar neurons, synaptic contacts, and supporting cells of Müller were demonstrated by scanning electron microscopy. It was found that the longer the cells survive in culture media they form constantly growing cell aggregates. After 12 days in vitro large multilayered cell complexes covered by an epithelioid cell layer had developed. Merely at the border of such aggregates typical retinal cells could be observed. The occurrence of a dense epithelioid cell layer covering the aggregate of neuronal cells is interpreted as a general adaptational reaction of the cells to the long lasting survival under in vitro conditions.

Animals↗

[Effect and tolerance of daily 2 X 1 g imipenem/cilastatin in general surgery].

The clinical efficacy, tolerability and safety of imipenem/cilastatin were studied in a open, prospective trial with 63 general surgical patients suffering from bacterial infections. According to study criteria, 48 of the patients were evaluable. Clinical cure was achieved in 47 of these 48 patients (97.9%). The causative organisms were eliminated in 39 of the 47 patients cured. Clinical side-reactions were observed in 4.2% of the 63 patients treated. In 8.3% of these laboratory parameters were changed. 77 of the 78 microorganisms isolated before therapy were sensitive to imipenem (MICs 0.02-2.0 mg/l). In one patient a coagulase-negative staphylococcus with an MIC of 16 mg/l was isolated after five days of therapy.

Adult↗