Functional and developmental morphology最新文献

The regional localization of acid and alkaline phosphatase (EC 3.1.3.2. and 3.1.3.1. respectively), determined histoenzymologically, is described in the cerebellum and medulla oblongata of Barilius bendelisis (Hamilton). Acid phosphatase activity in nuclear areas was observed to be moderately positive, whereas alkaline phosphatase activity varied from weak to strongly positive. The localization pattern of these enzymes in the fibre tracts differed. One interesting finding in this study was that the Purkinje cells in the cerebellum and the Mauthner cells in the medulla oblongata contained these enzymes in a high concentration. The contrasting cytological distribution patterns of the two enzymes indicate that their roles in the neurons and fibre tracts are probably different.

Duplication of the v. renalis was found in 11 of the regions examined (18.3%), when it was more frequent on the right side. A v. capsularis was found in 35 regions (58.3%), usually as a single vein. There were 1-3 vv. suprarenales (but mostly two; on the right they usually joined the v. cava caudalis and on the left the v. renalis sinistra). A v. spermatica was present on the right side in every case, but on the left side in 11 cases only; in one case it was duplicated. In the rat, the v. spermatica was rather thin; if absent, it was replaced by the v. deferentialis. In nine cases (60.0%) the v. uterina cranialis dextra opened into the v. cava caudalis, while in 12 cases (80.0%) the left vein opened into the v. renalis sinistra. A v. uterina media, draining blood from the caudal third of the cornu uteri, was found in only five cases (16.7%). The v. uterina caudalis drained blood from the corpus and cervix uteri. The v. ovarica was a constant finding; it was mostly joined by the v. lumbalis--and on the left side by the v. phrenica sinistra. In males, the vv. lumbales occurred mostly as a pair of veins lying just below the vv. renales. In females, they were present on both sides. As a rule, the v. iliolumbalis occurred as a single vein on both sides. The v. cava caudalis originated at the level of the transition between the lumbar and the sacral spine, usually at the confluence of the two vv. iliacae communes, which in 14 cases (46.7%) were joined by the v. sacralis mediana. Duplication of the v. cava caudalis was found in only one case (a female). Comparison of the morphology of the v. cava caudalis and its tributaries in the rat and the guinea pig showed more slight differences between the two species.

The effect of testosterone on the histological pattern of the gonads of the land snail Theba pisana was studied. It was found that testosterone accelerated spermatogenesis, as indicated by the large increase in the number of spermatozoa and the decrease in the number of primary spermatocytes. The diameter of the acini in treated snails was greater than in the normal controls. Conversely, testosterone led to reduction of the number of mature ova.

Approximately 60% of all human pregnancies terminate spontaneously before birth, mostly before being recognized. Exceptionally high prevalence of abnormalities has been found in this reproduction output. Original frequency of chromosomal (ChA) and developmental anomalies (DA) is not known, but may be very high. From 100 spontaneously aborted fetuses about 50 are ChA, approximately 70 are DA and only about 20 are without any pathological finding. Using data on ChA and DA distribution in newborns and those in abortuses--together with the knowledge on abortion rates in various gestation phases--the prenatal population structure may be reconstructed: in the pregnancy recognition phase about 7% ChA and 10-15% DA conceptuses remain in the population of surviving fetuses. Prenatal selection decreases gradually the frequency of anomalies to the values that are usually found in new-borns. The disappearance of particular anomalies is nonrandom, changing the malformation spectrum continually. The risk of prenatal elimination of the anomaly is not invariably proportional to the degree of phenotype damage of the fetus. Study of the hidden part of prenatal population offers the possibility to cover a considerably larger fraction of the whole reproduction output and supplies new valuable knowledge.

This study demonstrates a relationship between the biochemical properties of the extracellular matrix of a cartilaginous model of long bone and the fusion of mononuclear clastic elements into multinucleate chondroclasts. The results suggest that the chondroitin sulphate level in the extracellular matrix has an inhibitory effect on this process.

The aim of our work was to describe the fossa hypophysealis in the most common laboratory animal--in the rat, to measure its dimensions, to determine its stereotactic coordinates and to find the dependence of these coordinates on the age, weight and individual size of the skull in different rats. From this measurement we obtained data on the growth and possible shifts of the fossa hypophysealis but also found data facilitating the selection of animals to stereotactic operations so that the hit of the hypophysis be the most probable. There are suitable coordinates for bilaterally stereotactic intervention into the middle female rats hypophysis in conclusions of our work.

The coronary arteries of human foetuses from the 4th to 10th month of gestation were examined in the light and the electron microscope. Marked changes were demonstrated in the course of prenatal development, particularly in the media and adventitia (thickening, an increase in the number of collagen fibrils). In regions of coronary artery branching, here and there we found intimal pads or diffuse thickening of the intima, which were separated from the media by a mostly thin or discontinuous inner elastic membrane with an accumulation of smooth muscle cells and a smaller quantity of elastic fibrils. The intimal thickenings, which occurred mostly in the region of bifurcation of the left coronary artery and at sites where branches sprang from the r. ventricularis anterior of the left coronary artery, were already discernible at the beginning of the period in question (i.e. in the 4th month). In some cases, oedematous changes were found in the pads, where they were characterized by dilatation of the elastic membranes and smooth muscle cells by proliferating structureless matter.

The effect of the cytotoxic agent MTX on the mitochondrial content and on SDH activity in the jejunal mucosa of mice was studied. The control epithelium contained variable quantities of mitochondria, in the form of granules, short rods and filaments. In the crypt cells these organelles were larger than in the villus cells. The concentration of mitochondria close to the brush border and the basement membrane is indicative of their importance in production of the energy needed for active transport across the plasma membrane. After MTX treatment, there was a general decrease in the number, size and stainability of the mitochondria. In the control, SDH activity was moderate and its localization coincided topographically with the distribution of the mitochondria. The decrease in SDH activity after MTX, correlated to the decrease in the mitochondrial content, might be due to mitochondrial damage resulting form the indirect effect of MTX.

Autolytic changes in animal neurons 3 hours postmortem were compared with the changes in human material taken from the patients with ischemic heart disease. Relatively homogenous neuroplasm in the animal material was observed and the nuclei and nucleoli were present as well. Light artificial spaces were visible around the neurons. Marked vacuolization was in all cases of the human material. In some cases the nucleus with the nucleolus and mitochondria were still preserved. Majority of the neurons did not reveal the nucleolus and chromatin in their nuclei; destruction of the organelles and homogenization of the neuroplasm were dominant. We assume that the specific changes in the brain caused by the ischemic heart disease are different in comparison with the autolytic postmortal changes.