The relative antiquity of fenestrated blood capillaries and lymphatics,and their significance for the uptake of large molecules: an electron microscopical investigation in an elasmobranch

Résumé Le requin n'a pas de vrais vaisseaux lymphatiques, mais ses capillaires sanguins sont fénestrés. On suppose que les grandes molécules sont éliminées des tissus par ces fenestrae.     

The permeability of large lymphatics to ions,studied with the electron microscope

Résumé Les petites molécules s'échappent des grands vaisseaux lymphatiques grâce aux jonctions endothéliales intercellulaires, qui ne laissent pas passer les grandes molécules.     

The ischemic and postischemic effect on the uptake of neutral amino acids in isolated cerebral capillaries

Summary The uptake of some neutral amino acids was investigated in cerebral microvessels isolated from brains of gerbils subjected to bilateral cerebral ischemia with and without various periods of recovery. A transiently increased capillary uptake of³H-isoleucine,¹⁴C-cycloleucine and³H-phenylalanine was found in both conditions.     

The ischemic and postischemic effect on the uptake of neutral amino acids in isolated cerebral capillaries.

The uptake of some neurtral amino acids was investigated in cerebral microvessels isolated from brains of gerbils subjected to bilateral cerebral ischemia with and without various periods of recovery. A transiently increased capillary uptake of 3H-isoleucine, 14C-cycloleucine and 3H-phenylalanine was found in both conditions.     

Participation of the second extracellular loop of claudin-5 in paracellular tightening against ions, small and large molecules

Tight junctions control paracellular permeability. Here, we analyzed the impact of residues in the second extracellular loop (ECL2) of mouse claudin-5 on paracellular permeability. Stable expression of claudin-5_{wild type} in MDCK-II cells—but not that of mutants R145A, Y148A, Y158A or E159Q—increased transepithelial electrical resistance and decreased fluorescein permeation. Expression of claudin-5_Y148A, _Y158A or _E159Q enhanced permeability of FITC-dextran_10 kDa, which was unchanged in cells expressing claudin-5_{wild type} or claudin-5_R145A. In contrast, targeting to tight junctions, strand morphology and tight junction assembly were unchanged. It is concluded that R145 is unessential for trans-interaction of claudin-5, but necessary for tightening against small solutes and ions. The highly conserved residues Y148, Y158 and E159 in ECL2 of claudin-5 contribute to homo- and/or heterophilic trans-interaction between classic claudins and thereby tighten the paracellular space against ions, small and large molecules. These results provide novel insights into the molecular function of tight junctions.     

The relative effect of 2,3-diphosphoglycerate on the oxygen affinity of fetal and adult hemoglobin in whole blood

Riassunto Experimenti condotti sul sangue intero di individui neonati e adulti hanno dimostrato che l'affinità del sangue per l'ossigeno (P 50) dipende dalla concentrazione intraeritrocitaria di 2,3-difosfoglicerato (DPG) e dalle proporzioni relative di emoglobina adulta (HbA) e fetale (HbF). I risultati ottenuti indicano che nel sangue in toto l'effetto del DPG sulla P50 della HbF è circa il 40% di quello sulla P50 della HbA.     

The effect of abrin,anti-lymphocyte globulin and their conjugates on the immune response of mice to sheep red blood cells

Summary A chemical conjugate of anti-mouse lymphocyte globulin and abrin, is about twice as effective as a similar conjugate made with normal immunoglobulin and abrin, in suppressing the ability of the mouse to respond immunologically to an injection of sheep red blood cells.Acknowledgment. We thank Dr Stuart, Society of Herbalists, London, and Prof. G.C. Clark, Dept. of Botany, University of Ghana, for gifts ofAbrus precatorius seeds, and Mrs L. Bushby for help in the preparation of the horse anti-mouse lymphocyte globulin. D.C.E. is an external member of the staff of the Wellcome Foundation Ltd.     

Hyperglucagonemia,hypocalcemia and diminished gastric blood flow-evidence for an etiological role in stress ulcer of rat

Zusammenfassung Unter Zwangshaltung entwickeln intakte, scheinoperierte und adrenalektomierte Ratten eine Drosselung der Magenperfusion und unterschiedlich häufig Nekrosen und Erosionen in der Magenmukosa. Dieses Phänomen ist von einem erheblichen Anstieg an Pankreasglucagon begleitet, während Gastrin unter Stress eher abfällt.

---

---

Acknowledgment. We are gratefully indebted toK. Schwille, A. Wellmann andG. Besold for skillful technical assistance.     

The end of an error: Bianchini,Regiomontanus, and the tabulation of stellar coordinates

Archive for History of Exact Sciences - Giovanni Bianchini’s fifteenth-century Tabulae primi mobilis is a collection of 50 pages of canons and 100 pages of tables of spherical astronomy and...     

The rise of cryptographic metaphors in Boyle and their use for the mechanical philosophy

This paper tracks the development of Boyle's conception of the natural world in terms of the popular “book of nature” trope. Boyle initially spoke of the creatures and phenomena of nature in a spiritual and moral register, as emblems of divine purpose, but gradually shifted from this ideographic view to an alphabetical account, which at times became posed in explicitly cryptographic terms. I explain this transition toward cryptographic metaphors in terms of Boyle's social and intellectual milieu and their concordance with the reductive and conjectural character of the mechanical philosophical program.     

The effect of ether, pentobarbitone sodium and fentanyl on blood gases, acid-base balance and hematological parameters in the rat

Blood gases, acid-base balance and hematological parameters (RBC, PCV and Hb) were measured in adult rats of both sexes. The use of ether and fentanyl had a very little effect on the blood gases and acid-base balance. The induction of pentobarbitone anesthesia, however, was followed by a significant increase in PCO2 and TCO2, while the pH value decreased.