Distal axonopathy in streptozotocin diabetes in rats

Summary We noted the earliest morphological changes in the motor endplates 8 weeks after the induction of streptozotocin diabetes in rats. Morphometric measurements showed reduced axonal areas of the lateral plantar and the sicatic nerves in the diabetic rats 28 but not 2 and 8 weeks after the experiment. These findings suggested distal axonopathy.     

Scientific inertia in animal-based research in biomedicine

Despite aspirations to substitute animal experimentation with alternative methods and recent progress in the area of non-animal approaches, such as organoïds and organ(s)-on-a-chip technologies, there is no extensive replacement of animal-based research in biomedicine. In this paper, I will analyse this state of affairs with reference to key institutional and socio-epistemic barriers for the development and use of non-animal approaches in the context of biomedical research in Europe. I will argue that there exist several factors that inhibit change in this context. In particular, there is what I call “scientific inertia”, i.e. a certain degree of conservatism in scientific practice regarding the development and use of non-animal approaches to replace animal experimentation. This type of inertia is facilitated by socio-epistemic characteristics of animal-based research in the life sciences and is a key factor in understanding the status quo in biomedical research. The underlying reasons for scientific inertia have not received sufficient attention in the literature to date because the phenomenon transcends traditional disciplinary boundaries in the study of animal experimentation. This paper addresses this issue and seeks to contribute to a better understanding of scientific inertia by using a methodology that looks at the interplay of institutional, epistemic, and regulatory aspects of animal-based research.     

Cell-to-cell transmission in the activation of in situ nematocytes in acontia ofCalliactis parasitica

Summary It is reported that Ca²⁺-induced discharge of in situ nematocytes of acontia ofCalliactis parasitica can occur by cell-to-cell transmission along the acontial filament at a speed that averages 9.8·10^–3 cm^–1. The discharge is preceded by protrusion of nematocytes that proceeds along the acontium at a slightly higher speed.     

Dynamics of increase in muscle fibers in fishes in relation to size and growth

Summary Dynamics of increase of white myotomal muscle fibers of four species of freshwater teleosts (Salmo gairdneri, Pimephales notatus, Esox masquinongy andE. americanus vermiculatus) from three families (Salmonidae, Cyprinidae, Esocidae) representing a variety of maximum attainable sizes and growth rates, have been investigated. There are at least three major differences in these dynamics, and there appears to be an association between the ability of a fish species to attain large size (and grow fast) and its ability to recruit new fibers into this predominant tissue of the myotomal mass.     

Formation of proviruses in acute infection in vitro and in vivo

Summary Formation of DNA proviruses of RNA viruses, Sendai and Newcastle disease, was studied. DNA provirus of NDV was shown to be formed in mouse L-cells and Sendai DNA provirus in Ehrlich ascites carcinoma cells within 2–3 days post infection.     

Transesterification of juvenile hormone occurs in vivo in locust when injected in alcoholic solvents

Catabolism of juvenile hormone was studied in vivo in the African locust by injection of the labelled natural enantiomer (10R) (12-³H) JH-III. Due to the poor solubility of JH in aqueous solution, it was injected in a water-miscible solvent. Ethanol was chosen for its apparently low toxicity towards the locust. In these experimental conditions, reverse phase liquid chromatography procedure (RP-HPLC) coupled with on line radiodetection, revealed an apolar metabolite of JH-III. This compound was found both in adult females and in fifth stadium larvae. We demonstrate that this metabolite resulted from substitution of the carboxyl methyl group of JH-III by some hydrophobic moiety. This compound co-migrates in our RP-HPLC system with the JH analog epoxy-ethyl farnesoate (JH-III ethyl ester) obtained by KCN-catalysed transesterification of JH-III in ethanol. Both JH-III ethyl ester of chemical origin and biological compounds extracted from locusts give the same spectra when analyzed by gas chromatography-mass spectroscopy (GC-MS). Transesterification of JH-III was not observed with locust tissues incubated in vitro but occurred in vivo even if JH was injected in other alcoholic solvents such as propanol. Our data suggest that transesterification of JH-III occurred in vivo and underline the role of injecting solvent in in vivo studies.     

中国城市化进程中的环境抗争

城市化是经济社会发展的必然选择。然而,随着中国城市化飞速发展,也产生了城市水、大气、固体废弃物和噪声污染等一系列生态环境问题。同时,随着环境意识的增强,人们对居住环境质量的要求不断提高,致使城市化过程中环境抗争事件不断涌现。本文回顾了已有研究文献,以国外环境抗争、国内农村环境抗争与城市环境抗争作对比,突出城市环境抗争的特点;从抗争的情感基础、精英力量、弱组织化和互动过程四个方面对城市的环境抗争进行建构;从抗争力量、制度化因素、发展观念和社会力量四个方面分析当前环境抗争所面临的一系列困境。培育公民社会、更新地方政府的发展观念、加强社会科学与自然科学和管理科学之间的交叉研究等是应对当前困境最根本的出路。     

New intermediates in phaeomelanogenesis in vitro

Riassunto Mediante esperimenti in vitro, è stato accertato che i primi stadi della biosintesi delle feomelanine conducono alla formazione di derivati diidrobenzotiazinici, ai quali sono state assegnate le strutture III e IV.

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This investigation was supported by a grant from the Laboratorio di Chimica e Fisica per lo Studio delle Molecole di Interesse Biologico del C.N.R., Napoli.     

Periodicity in body temperature in man

Summary Body temperatures and self-assessed mood scales were recorded for 7 weeks or more by male volunteers. Auto-correlations of temperatures from the 21 subjects show evidence of a significant peak at the 20-day-interval. The self-assessed measure of Alertness (from 18 of them) also shows some evidence of rhythmicity, at the 22-day-period.     

Pollen flight forecasting in Germany and in Europe

Every tenth person in Central Europe is a pollinosis patient. The time of ripening and release of pollen, as well as pollen flight, all depend on the weather. Because each year is different from every other, mean values from pollen calendars do not provide any practical help for allergy-sufferers. For this reason, in many European countries, measuring networks have been established during the last 10 years as a basis for forecasting the prevalence of airborne pollen for the following 2–3 days, in connection with the weather forecast. Cooperation and communication also exist on a European level, and a European Pollen Database has been established.     

Hairiness in wool in relation to blood potassium types in Marwari sheep

Zusammenfassung Schafe mit geringem Kaliumgehalt im Blut haben an mehreren Körperstellen weniger markhaltige Haare als Tiere mit höherem K-Gehalt.     

Plasma 1,5-anhydroglucitol in experimental galactosemia in the rat

Summary Feeding with a galactose-rich diet induced a substantial drop in blood plasma 1,5-anhydroglucitol concentration. The decline was proportional to the dose of galactose. The decline was less marked in xylose-fed rats.     

Reversible reduction in bone blood flow in streptozotocin-diabetic rats

Summary Tibial growth and blood flow were both found to be markedly reduced in anaesthetised streptozotocin-diabetic rats compared to controls. Insulin treatment restored tibial growth to approximately control values and increased tibial blood flow to above control values. The observations are likely to be related to reduced bone turnover in uncontrolled diabetes.25 November 1986     

Changes in transglutaminase activity in carbon tetrachloride-damaged rat liver

Summary A significant decrease in transglutaminase (TGase) activity was observed in the cytosol and nuclear fractions of carbon tetrachloride-damaged rat liver. The degree of decrease in TGase activity in the cytosol fraction was closely related to the serum transaminase level. Gel filtration studies revealed that TGase activity in 80 kDa fractions significantly decreased, but that in 160 kDa fractions slightly increased after carbon tetrachloride treatment.