Microspectrofluorimetric analysis of the formaldehyde-induced fluorophores of 5-hydroxytryptamine and dopamine in intrapulmonary neuroepithelial bodies after administration ofl-hydroxytryptophan andl-DOPA

Summary To demonstrate the intracellular store of 5-hydroxytryptamine and dopamine in pulmonary neuroepithelial bodies of the neonatal rabbit after treatment with the corresponding amino-acid precursorsl-5-hydroxytryptophan orl-3,4-dihydroxyphenylalanine, formaldehyde-induced flourescence in combination with microspectrofluorimetric analysis has been used. Emission spectra and excitation spectra in an extended wavelength range from 240 to 460 nm, the displacement of excitation peaks after exposure to hydrochloric acid vapour, and calculation of peak ratio values 410/260, 380/320, 320/260 for phenylethylamine fluorophores and 385/315 for indolylethylamine fluorphores were performed. Thus, the presence of 5-hydroxytryptamine without occurrence of 5-hydroxytryptophan was demonstrated in pulmonary neuroepithelial bodies after administration of the corresponding biological precursor, while dopamine combined with 5-hydroxytryptamine were clearly revealed after administration ofl-3,4-dihydroxyphenylalanine. The rate of photodecomposition always corroborated these findings.Dedicated to Prefessor Dr. T.H. Schiebler on the occasion of his 65th birthdaySupported by grant nr. 3.0059.81 (to D.W.S.) from the Fund for Medical Scientific Research (Belgium)     

Fluorescence studies on aged and young erythrocyte populations

Structural changes in red blood cell (RBC) membrane are investigated by fluorescence techniques. Results obtained with three probes (DPH, 3-PM and fluorescamine) indicate a significant increase in membrane rigidity associated with aging of RBCs. Discrepancies between our observations and published data could arise from utilization of experimental conditions closer to physiological conditions in our study. Use of intact RBCs continuously manipulated in a 37 degrees C environment could represent experimental conditions favourable to the identification of rheologic membrane changes in senescent RBCs.     

Isolation of astrocytes,neurons, and synaptosomes of rat brain cortex

A simplified method was developed for the bulk separation of neuronal perikarya and astroglial celis from adult rat brain without the involvement of density gradients. Activities of various enzymes involved in glutamate metabolism were estimated and compared with those of synaptosomes. The activities of glutamate dehydrogenase and aspartate aminotransferase were higher in synaptosomes than in neuronal perikarya or glia. Glutamine synthetase was distributed in all the three fractions while glutaminase activity was higher in astrocytes than in synaptosomes and was not detectable in neuronal perikarya. The significance of these results in relation to metabolic compartmentation was discussed.     

A neural cocktail-party processor

Sensory segmentation is an outstanding unsolved problem of theoretical, practical and technical importance. The basic idea of a solution is described in the form of a model. The response of neurons within the sensory field is temporally unstable. Segmentation is expressed by synchronization within segments and desynchronization between segments. Correlations are generated by an autonomous pattern formation process. Neuronal coupling is the result both of peripheral evidence (similarity of local quality) and of central evidence (common membership in a stored pattern). The model is consistent with known anatomy and physiology. However, a new physiological function, synaptic modulation, has to be postulated. The present paper restricts explicit treatment to the peripheral evidence represented by amplitude modulations globally present in all components of a sound spectrum. Generalization to arbitrary sensory qualities will be the subject of a later paper. The model is an application and illustration of the Correlation Theory of brain function.This work has been supported by Grant I/37-821 of the Stiftung Volkswagenwerk.     

Immunohistochemical localization of neuropeptide Y in the guinea pig medulla oblongata

Summary The immunohistochemical localization of neuropeptide Y (NPY) was correlated with those of dopamine--hydroxylase (DBH) and vasoactive intestinal polypeptide (VIP) by mapping serial 7 m paraffin sections at three levels of the guina pig lower brainstem: a) area postrema, b) dorsal motor nucleus of the vagus, and c) nucleus prepositus of the hypoglossal nerve. Based on differences in transmitter expression, three populations of NPY-immunoreactive (IR) neurons were distinguished: NPY-IR catecholaminergic cells (NPY/CA), NPY-IR VIP-ergic cells (NPY/VIP), and NPY-IR cells which were not reactive to either DBH or VIP. Within these populations, size differences among neurons in characteristic locations allowed differentiation among the following subpopulations: NPY/CA neurons in the lateral reticular nucleus — magnocellular part (mean neuronal size 538 m²) and parvocellular part (318 m²)-, in the vagus-solitarius complex (433 m²), and in the dorsal strip (348 m²); NPY/VIP neurons in the vagus-solitarius complex (368 m²) and in the nucleus ovalis (236 m²). Apart from scattered NPY-IR cell bodies in the regions listed above, NPY-IR cell bodies in the lateral portion of the nucleus solitarius and in the caudal part of the spinal nucleus of the trigeminal nerve did not exhibit IR to either DBH or VIP. NPY-IR neurons in the area postrema occurred too infrequently for co-localization studies. The differential distribution of heterogeneous NPY-IR cell subpopulations may reflect the involvement of NPY in a variety of neuronal functions.Supported by the Deutsche Forschungsgemeinschaft, grant He 919/6-1     

Histochemical studies on the lipids in the epithelium of the fetal colon

Summary Large intestines from 30 fetuses with crown-rump lengths ranging from 26 to 180 mm have been studied histochemically as to their epithelial content of lipids. These lipids have been localized intracellularly and basally in the cells, and comparative studies of the colon and the small intestine have demonstrated that there are considerable amounts of lipids in the colon as compared with the small intestine.It is concluded that the main part of the lipids consist of saturated and unsaturated constituents.The possible explanations of the lipids as absorbed material, biological active material synthetized de novo or as material involved in the metabolism of fetal surface cells are discussed.This work was supported by a grant from the Aid of the Crippled Children, New York.     

Zur Verbreitung der ABO-Blutgruppen in der Bevölkerung Nordthailands

2048 subjects in North Thailand were examined for AB0 blood groups. A control group representative of the population of the provinces of Chiengmai and Lampun was formed of 382 examinees and 3403 blood donors.The distribution of AB0 groups in this population is similar to that of Central Thailand. Some ethnic groups show significant deviations: The Miao tribe, originating in South China, has a much higher frequency of B. There was a significant reduction in gene A and B in the younger generation of this tribe. The Thai Yong, people who migrated to North Thailand from Yunnan in the 19th century, show an AB0 distribution similar to Chinese in Yunnan. They differ significantly from the Northern Thai. There is also a difference in the distribution of -thalassaemia and hemoglobin E between these two groups.Male leprosy patients showed an excess of group A which was not present in female patients. The percentage of severely ill patients was much higher in the males. Differentiation into lepromatous and tuberculid forms is not available. Among 108 people who had suffered from smallpox approximately 20 years ago there was an excess of groups 0 an B in comparison to the control group.

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Mit Unterstützung durch die Deutsche Forschungsgemeinschaft.     

Burrowing,grooming, and feeding behaviour of Paraceradocus,an antarctic amphipod genus (Crustacea)

Summary Species of the amphipod genus Paraceradocus found near the Antarctic Peninsula were observed in aquaria. The animals live under stones in burrows in sediment which they excavate with their gnathopods. During burrowing the animal regularly turns backwards in a somersault-like movement. Paraceradocus feeds on detritus, which is manipulated by the gnathopods and the antennes. The gnathopods are also used for grooming. A dense brush of setae at the medial surface of the carpi of the gnathopods I is used to clean off fine particles from the antennes. These particles are transferred to the maxillipeds and are ingested. The rear appendages are mainly cleaned by the gnathopods II. Young animals sitting between the gnathopods of the adult participate in feeding.     

Biochemical bone marrow markers and their significance in postmenopausal osteoporosis--a new method in the diagnosis of osteoporosis?]

This study analyzes the qualification of biochemical markers in the diagnosis of osteoporosis and evaluates the potential of a multiparametric classification of premenopausal and non-osteoporotic as well as osteoporotic postmenopausal women, which is based on biochemical marker profiles. For this evaluation data of 29 women in the age between 28-74 years were used. The classification of osteoporosis was done by the trabecular density of the lumbar spine using qCT-measurements. The biochemical markers of formation and resorption AP, bAP, OC, ucOC, PICP, PYD, DPD, NTX, BSP and vitamin K were analyzed on day 1 and 42 in all patients. For vitamin K we found significant distribution differences between non-osteoporotic and osteoporotic women (p<0.005). The crosslinks PYD and DPD showed weakly significant differences. All other parameters exhibited non-significant results. Vitamin K acted with a sensitivity of 64% and a specificity of 82%. The used multiparameter classification process improved sensitivity and specificity considerably. The parameter profiles of OC/PYD, vitamin K/PYD and vitamin K/bAP revealed the highest sensitivities with specificities of more than 82%.