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Biomedical subjects

E Marani

Publications and source records attributed to E Marani.

137 records · Page 8Linked to original sources
PubMed1978

A method for orienting cryostat sections for three-dimensional reconstructions.

Tissue for cryostat sectioning is embedded together with reference tissue impaled on the needles of a specially constructed trident. To maintain spatial orientation, reference and experimental tissue are frozen in Tissue-Tek O. C. T. compound in the manner usual for enzyme histochemistry using a simply constructed carrier. The trident is removed by heating its handle, thus leaving holes in the reference tissue which in turn are used as reference points to orient successive sections with respect to each other.

Animals↗
PubMed1977

Acetylcholinesterase staining in subdivisions of the cat's inferior olive.

The present paper describes a unique distribution of true AChE activity in the IO. In the dorsal accessory olive three areas with high AChE activity can be distinguished. The medial accessory olive can be subdivided into a caudal part which shows rostro-caudally directed bands with different enzymatic activity, and a rostral part which shows a more uniform, medium activity. In the nucleus beta and the dorso-medial cell column, AChE activity is low. The ventral and dorsal lamellae of the principal olive contain areas with high, medium, and low activity. The dorsal cap is strongly positive, while the ventrolateral outgrowth is negative for AChE. Enzyme distribution cannot be fully explained on the base of the known afferent and efferent connections with the IO. However, histochemical results provide evidence that generally supports a subdivision of the IO that mirrors these connections (Brodal, '40; Armstrong et al., '74' Boesten and Voogd, '75; Groenewegen et al., '75).

Acetylcholinesterase↗
PubMedDate not supplied

Brain enzyme histochemistry following stabilization by microwave irradiation.

The activities of various enzymes present in brain homogenates were assayed biochemically (a) with no pretreatment, (b) following a standard microwave treatment in saline and (c) after a standard microwave treatment in formalin. All enzyme activity was lost after the microwave - formalin in treatment. Following microwave - saline treatment, the activities of alkaline phosphatase, 5'-nucleotidase, isocitrate and succinate dehydrogenases were reduced. In contrast, the activities of lactate and malate dehydrogenases were unchanged, and that of acetylcholinesterase apparently increased. Analogous outcomes were seen following attempted histochemical demonstrations of these enzymes. Thus satisfactory histochemical demonstration of all enzymes was achieved (except with alkaline phosphatase, lactate and malate dehydrogenases) following the microwave-saline pretreatment. Since acid phosphatase, catalase and peroxidase were also successfully demonstrated, it seems that microwave-saline pretreatments permit both retention of sufficient enzyme activity for histochemical demonstration to occur and retention of sufficient structural integrity for critical morphological investigations. Since the failure to stain the sites of lactate and malate dehydrogenases is not due to microwave inactivation of these enzymes, their demonstration may be possible by varying the staining procedures.

Animals↗
PubMedDate not supplied

The use of microwave irradiation with low formalin concentrations to enhance the conversion of dopamine into norsalsolinol in rat brain: a pilot study.

The fixation of the neurotransmitter dopamine in the central nervous system by perfusion with formalin solutions seems to take place mainly via the formalin-induced condensation product norsalsolinol. In the present investigation the influence of microwave irradiation of the formalin-induced condensation of dopamine was studied in vitro and in vivo by making use of different, relatively low, formalin concentrations. It appeared that in vitro and in vivo the dopamine conversion was complete with 4% formalin and no influence of microwaves was noted. However, by making use of much lower formalin concentrations (0.2% and 0.4%) the condensation of dopamine was strongly augmented, in vitro (200%) and in vivo (at least 500%) using microwave techniques. There was a considerable loss in non-microwaved tissue (30%) after perfusion in vivo. This was lower (10%) in microwaved tissue. In experiments with perfused brain tissue which allowed a more complete calculation, a loss was found. This might be caused by a strong binding of dopamine and/or norsalsolinol to tissue components or to side reactions that could not be traced by the present experimental techniques.

Animals↗