Effects of the antiprotease Trasylol® on peripheral blood leucocytes

Summary Binding of the antiprotease Trasylol^® to human peripheral blood lymphocytes and polymorphonuclear leucocytes (PMNs) was demonstrated at the ultrastructural level using an indirect immunoperoxidase technique. This also revealed endocytosis of membrane bound Trasylol by PMNs. Trasylol inhibited PHA- and Con A-induced lymphocyte stimulation, and was cytotoxic to unstimulated cells.One of us (D.J.T.) is supported by Bayer Pharmaceuticals Ltd., from whom we also acknowledge a generous supply of Trasylol.     

On the use of a peptidase inhibitor (trasylol) for storage of I125-labelled peptide hormones (HGH,TSH, ACTH,insulin, glucagon,PTH)

Zusammenfassung Von den untersuchten J¹²⁵-markierten Peptidhormonen sind HGH und TSH auch ohne Trasylol gut haltbar. Die mässige Degradation von Insulin und die rasch zunehmende Degradation von PTH und Glukagon kann durch Trasylol (500 E/ml) verhindert werden. Für ACTH ist eine Kombination von Trasylol mit 0.5% Mercaptoethanol erforderlich.     

The in vitro effect of aprotinin upon spleen cells from normal and tumour-bearing mice exposed to PPD and tumour cells

Aprotinin (Trasylol) is shown to enhance the response of spleen cells from normal and tumour bearing mice to PPD nd tumour cells. This enhancement is greater in the tumour-bearing mice.     

The in vitro effect of aprotinin upon spleen cells from normal and tumour-bearing mice exposed to PPD and tumour cells

Summary A protinin (Trasylol) is shown to enhance the response of spleen cells from normal and tumour bearing mice to PPD and tumour cells. This enhancement is greater in the tumour-bearing mice.Acknowledgments. We are grateful to Bayer (U.K.) Limited for generous supplies of aprotinin. The PPD was supplied by the Ministry of Agriculture. The work was supported by a grant from the North of England Cancer Research Campaign.     

Capping of concanavalin A- or ricin-binding sites does not influence phagocytosis in polymorphonuclear leukocytes

Summary Rabbit polymorphonuclear leukocytes (PMNs) were capped with territin-conjugated concanavalin A or ricin, and then allowed to phagocytose yeast cells. Phagocytic activity and lectin distribution were determined by ultrastructural morphometry. Capped PMNs were found to phagocytose as efficiently as control PMNs, and always to ingest the particles with a lectin-free portion of their plasma membrane. This clearly indicates that concanavalin A- and ricin-binding sites of the PMN membrane are not involved in the recognition and phagocytosis of yeast particles.     

Collagen breakdown by gingival collagenase and elastase

Summary The granule fraction of human polymorphonuclear leucocytes (PMNs), the concentrated product of gingival washing from 2 human volunteers and the culture fluid of samples of human gingiva were incubated with neutral salt soluble collagen from rat skin and the patterns of collagen degradation were studied by SDS polyacrylamide gel electrophoresis. Collagenase from human gingiva cleaved the collagen molecules in a fashion similar to that of the PMN granule fraction. Collagen was also attacked by elastase from human PMNs and, to a lesser extent, by elastase from the gingival washings.Supported by a grant of Swiss National Fund for Scientific Research No. 3.604.0.75.Acknowledgments. We thank Prof. M. Baggiolini, Wander S.A., Bern for his helpful advice. We are very grateful to Mrs I. Condacci and Miss E. Andersen for their skillful technical assistance.     

Ginkgo biloba extract inhibits oxygen species production generated by phorbol myristate acetate stimulated human leukocytes

A Ginkgo biloba extract (Gbe) containing flavonoids, among other compounds, was tested for the release of activated oxygen species (O-2, H2O2, OH.) during the stimulation of human neutrophils (PMNs) by a soluble agonist. The extract slows down O2 consumption (respiratory burst) of stimulated cells by its inhibitory action on NADPH-oxidase, the enzyme responsible for the reduction of O2 to O-2. Consequently, superoxide anion (O-.2) and hydrogen peroxide (H2O2) production is significantly decreased when the PMNs stimulation is done in the presence of the extract at concentrations of 500, 250 and 125 micrograms/ml. Moreover, the hydroxyl radical generation (OH.) is very much decreased at concentrations as low as 15.6 micrograms Gbe/ml, which indicates that the extract also has free radical scavenging activity. Gbe is able at least to reduce very severely the activity of myeloperoxidase contained in neutrophils. This enzyme, secreted into the intra and extracellular medium, catalyzes the oxidation of chloride (Cl-) by H2O2 to yield strong oxidants (HOCl, chloramines) which are implicated in inflammatory processes.     

Lactoferrin

Lactoferrin is an iron-binding glycoprotein of the transferrin family. Abundant expression and secretion of lactoferrin, in particular in milk and fluids of the digestive tract, are related to its implication in the first line of host defense. Lactoferrin is also a prominent component of the secondary granules of neutrophils (PMNs) and is released in infected tissues and blood during the inflammatory process. In addition to its direct antimicrobial properties, the abilities of lactoferrin to regulate the immune response and to protect against infection and septic shock have been described in numerous in vitro and in vivo studies. Although the cellular and molecular mechanisms that account for the modulation of the inflammatory and immune responses by lactoferrin are not yet totally elucidated, many are now established. At the cellular level, lactoferrin modulates the migration, maturation and function of immune cells. At the molecular level and in addition to iron binding, interactions of lactoferrin with a plethora of compounds, either soluble or membrane molecules, account for its modulatory properties. This paper reviews our current understanding of the cellular and molecular mechanisms that explain the regulatory properties of lactoferrin in host defence.     

Ginkgo biloba extract inhibits oxygen species production generated by phorbol myristate acetate stimulated human leukocytes

Summary A Ginkgo biloba extract (Gbe) containing flavonoids, among other compounds, was tested for the release of activated oxygen species ( , H₂O₂, OH^.) during the stimulation of human neutrophils (PMNs) by a soluble agonist. The extract slows down O₂-consumption (respiratory burst) of stimulated cells by its inhibitory action on NADPH-oxidase, the enzyme responsible for the reduction of O₂ to . Consequently, superoxide anion ( ) and hydrogen peroxide (H₂O₂) production is significantly decreased when the PMNs stimulation is done in the presence of the extract at concentrations of 500, 250 and 125 g/ml. Moreover, the hydroxyl radical generation (OH^.) is very much decreased at concentrations as low as 15.6 g Gbe/ml, which indicates that the extract also has free radical scavenging activity. Gbe is able at least to reduce very severel the activity of myeloperoxidase contained in neutrophils. This enzyme, secreted into the intra and extracellular medium, catalyzes the oxidation of chloride (Cl^–) by H₂O₂ to yield strong oxidants (HOCl, chloramines) which are implicated in inflammatory processes     

Frederick Pavy (1829-1911) and his opposition to the glycogenic theory of Claude Bernard

For more than 50 years the Guy's Hospital physician Frederick Pavy (1829-1911) attempted to discredit the theory of his erstwhile teacher, Claude Bernard, that liver glycogen was broken down to supply sugar to the systemic circulation. His opposition was driven by his clinical perceptions and was based on two assumptions: the first was that the kidney was a simple filter through which small molecules would diffuse, so that sugar had to be prevented from reaching the systemic circulation. For Pavy, the liver was the barrier. The second was teleological: he could not believe that nature would operate in what he saw as a defective way, i.e. converting sugar into glycogen and then back again. At the beginning of his long working life Pavy regarded himself as a physiologist and was critical of the stagnancy of English physiology which was kept afloat by amateurs like himself in whatever time they could spare from busy private practice. At the end he came to see his own view of carbohydrate metabolism as symbolic of the schism between responsible clinicians (himself) and irresponsible daydreaming physiologists (his opponents).     

Stimulation of proliferation of rat spleen cells, in vitro, by a nonspecific acute inflammatory exudate. Modulation of cell response to phytohemagglutinin (PHA)]

The effect of an acute non-specific inflammatory exudate with mitogenic activity on macrophages in culture has been tested on the spontaneous and PHA-induced DNA synthesis of spleen cells in vitro. Stimulatory effect of this exudate was observed on spontaneous DNA synthesis which was detectable over a range of 1 : 4 to 1 : 4,000 concentrations. After optimal PHA stimulation, an inhibition of mitogen-induced DNA synthesis was observed when the cells were exposed to the highest concentrations (up to 1 : 128) of the exudate. Thereafter, the phenomenon could be reversed and the stimulation was maximal at a concentration of 1 : 2,000. When a sub-optimal dose of PHA was used, the simulatory effect was more pronounced and detected from 1 : 8 up to 1 : 4,000 concentrations.     

溧阳市沙河水库东副坝溃坝生命损失估算

应用溃坝洪水软件BREACH和FLDWAV分析溧阳市沙河水库东副坝在100年一遇设计洪水位23．17m时下游坡高程点8．40m处管涌诱发溃坝的洪水状况，确定大致的淹没范围，计算了溃坝洪水的严重性，估算了风险人口，应用Graham法定量地估算了生命损失，重点研究了生命损失与警报时间的关系，提出了确保2h警报时间的建议，加强非工程措施，避免生命损失。     

New lectins and other putative adhesins in Aeromonas hydrophila

The ability of strains of Aeromonas hydrophila to bind 125I-labelled collagen types I and IV, fibronectin, laminin, lactoferrin, and immobilized mucins and orosomucoid on latex beads was found to be a property common to all the isolated strains. The binding was specific, was inhibited by homologous unlabelled glycoproteins, and was protease sensitive. The nature of the binding is discussed.     

Biodegradation of nitrilotriacetic acid (NTA) in the absence of oxygen

Summary A microbiol culture able to grow in the absence of oxygen with nitrilotriacetate (NTA) as the sole source of carbon and energy was enriched from river sediment. Growth was strictly dependent on the presence of nitrate and the results indicate that nitrate was exclusively used as the electron acceptor and was reduced to dinitrogen (N₂). The stoichiometry of anaerobic NTA degradation by the enrichment culture was determined.     

Growth and longevity of Wistar rats receiving a diet whose protein content is rapidly lowered in relation to aging]

Growth and longevity of the Rats were the same when: (i) the diet was rich in casein (21%), from weaning to death: (ii) the casein content of this diet (without B12) was progressively lowered from weaning to 200 days of age, and thereafter was 7%. When the casein level had been too rapidly lowered, inducing retardation of growth after 75 days, maximal growth was lowered and life span was increased.     

Y型明渠交汇水流分离区的数值分析

针对Y型明渠交汇口的水流特性，应用三维各向异性的雷诺应力模型，采用交错网格上的有限体积法离散控制方程，用SIMPLE算法求解压力-速度场。数值计算结果与物理模型试验结果吻合较好，并据此重点探讨了不同交汇角条件下交汇口分离区尺寸的变化规律，提出Y型交汇水流分离区的定义和分离区尺寸与汇流比的函数关系。     

Inhibition of collagen synthesis by interleukin-1 in three-dimensional collagen lattice cultures of fibroblasts

Interleukin-1 (Il-1) was added to collagen lattice cultures of human skin fibroblasts. No cell division was induced, the ability of fibroblasts to contract the lattices was decreased and a dose-related inhibition of collagen synthesis without effect on non-collagen proteins was found. Indomethacin had no influence on these effects.     

家蚕体内不同部位的同步辐射成像分析

以五龄熟蚕为研究对象，对其体内不同部位进行同步辐射成像（包括同轴位相衬度成像和显微断层成像）。研究结果表明，蚕体内中部丝腺的直径范围在3．74～4．21mm之间，其始端距离蚕头部约18mm。而吐丝管则被发现于距离蚕头部顶端1．43mm处，且直径相对较细，范围在7～52μm之间。     

Robert Boyle and the heuristic value of mechanism

This paper argues that, contrary to the claims of Alan Chalmers, Boyle understood his experimental work to be intimately related to his mechanical philosophy. Its central claim is that the mechanical philosophy has a heuristic structure that motivates and gives direction to Boyle's experimental programme. Boyle was able to delimit the scope of possible explanations of any phenomenon by positing both that all qualities are ultimately reducible to a select group of mechanical qualities and that all explanations of natural phenomena are to be in terms of the operations of machines and are to appeal only to qualities that are already familiar. This is illustrated by his investigations into the Torricellian experiment. Boyle's explanation of the elevation of the mercurial cylinder by appeal to the spring of the air was an intermediate mechanical explanation. Boyle was convinced that the spring of the air was ultimately reducible to the mechanical qualities. This in turn had implications for his research into the cause of respiration. In a move that was both parsimonious and consistent with the broad requirements of the mechanical philosophy, Boyle was able to solve the problem of the cause of the inflow of air into the lungs by appeal to his research in pneumatics. This application of a mechanical explanation in pneumatics to physiology is just what one would expect if the mechanical philosophy was as universal as Boyle claimed it to be. Therefore, far from Boyle's experiments having a life of their own, they were clearly directed by and understood in terms of the mechanical philosophy.     

Inhibition of collagen synthesis by interleukin-1 in three-dimensional collagen lattice cultures of fibroblasts

Summary Interleukin-1 (II-1) was added to collagen lattice cultures of human skin fibroblasts. No cell division was induced, the ability of fibroblasts to contract the lattices was decreased and a dose-related inhibition of collagen synthesis without effect on non-collagen proteins was found. Indomethacin had no influence on these effects.