Morphologic and cytochemical study of Sertoli cell nuclei in ruminants]

Nuclei and nucleoli were examined at an ultrastructural level in the testicular tissue of bulls and rams. In the two species there occurs a morphologically interesting so called multivesicular nuclear body; the interpretation of its function is not quite clear. The tissue was processed by a routine electron microscope technique and than a cytochemical demonstration of several types of proteins was used. Acidic argyrophilic proteins were demonstrated by a silver-staining technique, basic lysine-rich proteins by means of ethanolic PTA, and ribonucleoproteins (RNP) by the method of Bernhard's regressive preferential staining. Multivesicular nuclear bodies in bull Sertoli's cells are composed of a greater number of membrane bound vesicles with granules on the outer surface (Fig. 1). The results of cytochemistry reactions show that the granules contain acidic argyrophilic proteins (Fig. 3) and RNP (Fig. 7). The intervesicular material is an analogy of the dense fibrillar component of normal nucleoli of somatic cells. This component contains the three types of investigated proteins (Figs. 2, 3, 5, 7). In the nuclear bodies of ram Sertoli's cells the number of vesicles is much lower, the fibrillar component is prevailing, in form of clusters and striae of filamentous material around the vesicles. The cytochemistry reactions proved that this material contains acidic argyrophilic proteins (Fig. 4) and basic PTA positive (Fig. 6) proteins. The presence of acidic and basic regulatory proteins in the fibrillar component of multivesicular nuclear bodies indicates the active synthesis of RNA occurring in this material. It is therefore possible to consider this special type of nuclear bodies as a full equivalent of nucleoli of somatic cells as to the function.     

Use of mass spectrometry in the chemical analysis of organophosporus compounds]

The authors studied the possibility of using mass spectrometry in the chemical analysis of the biologically highly active organophosphorus compounds. The results show that methylthiophosphorous acid O-ethyl-S-(2-dimethylaminoethyl) ester has the most complex mass spectrum of all the substances under study. In the spectrum characteristic fragments were detected, having m/e values of 42, 44, 58, 71 and 72 [corresponding to the presence of the (CH3)2NCH2CH2-group], and 81, 95, 97, 105 and 125 which are characteristic of the phosphoester group. Mass spectrometric analysis, performed in this study, proved that the MS method is suitable for a qualitative analysis of biologically highly active organophosphorus compounds such as methylthiophosphorous acid O-ethyl-S-(2-dimethylaminoethyl) ester.     

CANINE BRAIN ANATOMY ON MAGNETIC RESONANCE IMAGES

Magnetic resonance (MR) images of the canine brain were acquired during investigation of dogs with neurologic disease. A paramagnetic contrast medium was used for enhancement. MR provided images with excellent contrast between grey and white matter, as well as brain tissue and cerebrospinal fluid. Good resolution and anatomic detail of the canine brain were obtained. A series of images was compiled and labelled as a reference for MR anatomy of the canine brain.     

Ultrastructural study of the hypothalamic region after administration of aurothioglucose in mice]

Aurothioglucose dose of 1 mg g-1 1. w. was applied intraperitoneally to experimental female mice. After 24 hours the animals were decapitated and samples for ultrastructural examination were immediately taken from the region of the hypothalamic ventromedial nucleus. The following findings were obtained from the study of 243 electronograms of 8 experimental animals: 1. dense round particles 0.034 to 0.016 mu in size, representing the gold of aurothioglucose; 2. parenchymatous dystrophy of the mitochondria; 3. peeling off of the individual layers of myelin sheath and the granularity of these layers corresponding to the disintegration of nerve fibres.     

Can place names be used as indicators of landscape changes? Application to the Doñana Natural Park (Spain)

This work broaches the possibility of using place names as indicators of original landscapes that have been much transformed. The reconstruction of landscape elements from place names is commonly disputed because such daring notion is impossible to demonstrate. The present case avoids this by making a preliminary study of changes in the landscape using conventional methods. With the knowledge gained from objective and reliable sources, the possibility is analyzed of whether place names are a reflection of landscape changes taking place over a considerable period of time (the last few centuries). It is concluded that, for the present case study, in natural areas with a high rate of change of land use (Doñana Natural Park), place names indicate not only changes in the landscape, but also how such changes are perceived. In the study area, this is especially clear regarding the fens.     

Initial experience with the intravenous administration of colloidal carbon to cattle in relation to the incidence of mastitis

The influence was studied of intravenous application of colloid carbon to ten dairy cows of Bohemian Spotted breed in the seventh to eighth months of gravidity, as exerted on the health condition of mammary glands and on milk yield in the subsequent lactation. The cure consisted of three i. v. installations in 72-hour intervals; one dose contained 150 mg carbon in 20 ml of 20% glucose. No adverse by-effects were observed in the course of application and after it. During the subsequent lactation period (nine months) the test cows exhibited a better health condition of mammary glands if compared with the control group (ten dairy cows). In the test group no case was recorded of the clinical form of mastitis while in the control group one case of acute mastitis and two cases of chronic mastitis occurred. S. agalactiae was not isolated at all in the test group while in the control group it was isolated in two cows. S. aureus was also isolated more times (in 32 cases) in the control cows than in the test ones (in 27 cases). A higher average counts of cells in udder-quarter milk samples were found in the test group only at the onset of lactation (from the third month after calving), the average counts of cells over the whole period under study were however lower in the test group (1 380 000 per ml) than in the control group (1 234 000 per ml). The average daily milk yield per cow in the test group exceeded the average milk production in the control group in the period of study. An increase by 1.630 1 as compared with the untreated cow was observed in the average milk yield. It has been demonstrated by the results that by the intravenous instillation of colloid carbon nonspecific natural defensive mechanisms of dairy cows, mainly leucocytes, are stimulated, which enhanced the cell readiness to react to infectious process (mastitis) and overall injury of the organism (sepsis).     

An ELISA with Brucella lipopolysaccharide antigen for the diagnosis of B. melitensis infection in sheep and for the evaluation of serological responses following subcutaneous or conjunctival B. melitensis strain Rev 1 vaccination.

An indirect enzyme-linked immunosorbent assay (ELISA) with unpurified Brucella melitensis smooth lipopolysaccharide (S-LPS) as antigen was evaluated for the serological diagnosis of B. melitensis infection in sheep in comparison with the Rose Bengal (RB), complement fixation (CF), radial immunodiffusion (RID), microplate agglutination (MA) and rivanol agglutination (RIV) tests. Tests RB and CF detected as positive each of the 77 sera from B. melitensis-infected animals tested, the RID (74), MA (76) and the RIV (72) were less sensitive. However, all tests compared were negative when 77 sera from Brucella-free rams were tested. While subcutaneous Rev 1 vaccination induced high response levels in any of the tests, low level responses were obtained upon conjunctival vaccination, particularly in ELISA and RID tests.