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PubMed1976

[Findings and significance of spermatozoa agglomeration in the semen].

Agglomeration of spermatozoa (pseudo-autagglutination, clumping of spermatozoa) is distinguished from agglutination in immunological processes by the coarse meshwork of the spermatozoa clumps and the central inclusion of epithelia, leukocytes, residual bodies, spermatozoa with persisting cytoplasmatic droplets, as well as parts of viscous seminal plasma. In 658 semen samples of out-patients with barried marriage, spermatozoa agglomerations were seen in 13.4% of the samples immediately after liquefaction while in additional 6.7%, they were found up to three hours later. The agglomeration phenomenon is typical but not specific of the so-called vegetative congestion syndrome, appearing concomitant with high spermatozoa counts, normal rate of spermatozoa motility and morphology, as well as an increase in residual bodies and spermatozoa with persisting cytoplasmatic droplets. Next to congestion syndrome, spermatozoa agglomerations may also result from post-inflammatory disturbances of epididymal or accessory gland function whereas in florid stages of inflammation, they are rarely observed. As the congestion syndrome may give rise to male infertility in some cases, andrologists should be acquainted with its clinical and spermatological symptoms with special regard to therapy.

Chronic Disease↗
PubMed1976

Absorption of cholesterol by the gallbladder.

To study whether cholesterol is absorbed by the gallbladder, we instilled from 1 to 300 nmoles of [4-14C]cholesterol dissolved in 1 ml of guinea pig bile into the in situ guinea pig gallbladder. The bile used in these experiments contained 7 mumole/ml bile acid, 27 nmole/ml lecithin, and 8 nmol/ml cholesterol. To this bile, we added the radioactive cholesterol, from 0 to 1 mumole/ml egg lecithin, and 100 mug/ml of bromosulfophthalein, a nonabsorbable marker. After 1 nmole [4-14C]cholesterol was instilled in bile without added lecithin, 77 +/- 8% of the radioactivity was demonstrated to be in the gallbladder wall 6 hours later. The proportion of cholesterol absorbed by the gallbladder decreased as the concentration of added lecithin or bile salts was increased. Radioautography showed radioactivity in the mucosa, and subcellular fractionation of homogenized cells by centrifugation showed cholesterol in the mitochondrial (23 +/- 4%) and microsomal (18 +/- 4%) fractions. Studies on specific activity suggested that there was net absorption of cholesterol and not merely an exchange of cholesterol in the contents for cholesterol in the wall. This study presents evidence that significant quantities of cholesterol but not cholesterol ester can be absorbed by the guinea pig gallbladder. We also found that the absorbed cholesterol can be converted to cholesterol ester and the relevance of these findings to cholesterosis in man are discussed.

Animals↗
PubMed1976

The formation of the gonadal ridge in Xenopus laevis. III. The behaviour of isolated primordial germ cells in vitro.

Previous studies have described the morphology, including the ultrastructure, of primordial germ cells (PGCs), and the cells with which they associate to form the gonadal ridge, in Xenopus laevis. In order to test their capacity for active movement we have studied single, isolated PGCs in vitro. Time-lapse studies of these cells reveal that they are motile, using broad cytoplasmic processes. The fact that these cells are very large and easy to manipulate in vitro makes them an attractive subject of study, particularly with respect to the mechanism of their movement and the surface phenomena which guide them to the site of the gonadal ridge.

Animals↗
PubMed1976

Sensitivity of tumour and normal cells to the effect of immune lymphocytes in vitro and some properties of target cells determing this sensitivity.

Cells from various spontaneous mammary tumours of C3H/He mice differ in their sensitivity to immune allogeneic lymphocytes in vitro. Two cell lines, differing in their sensitivity to allogeneic immune lymphocytes in vitro, were obtained from spontaneous mammary tumours which developed in C3H/He mice. Of these two lines, the cell line MT3 was considerably more immunoresistant than line MT5, as demonstrated by microcytotoxic tests in vitro. Furthermore, only the immunoresistant MT3 cell line was capable of growing in syngeneic hosts. During passages in vitro, cells of the line MT5 became as immuno-resistant as cells of the line MT3; concomitantly, cells of the line MT5 started to take in syngeneic hosts. Cell immunosensitivity to immune allogeneic lymphocytes in vitro correlates with that cell property which determines the penetrance rate of intact allogeneic and syngeneic lymphocytes into these cells (emperipolesis). Non-tumourous cells from different C3H/He mouse tissues were more immunoresistant than tumour cells from the two cell lines cultured.

Animals↗
PubMed1976

The occurrence of a "SME"-defect-like abnormality in the head of spermatozoa from a Norwegian Landrace boar.

A spermhead-defect appearing in 15-20 per cent of the spermatozoa from a Norwegian Landrace boar with a slightly impaired fertility was studied in light and electron microscope. The defect had the shape of a circumferential, somewhat elevated area containing a cystic structure located within the nucleus. In some of the sections observed in electron microscope a communication could be found between the cyst and the acrosome, indicating that a deviating development of the latter could be involved in the formation of the defect. In some spermatozoa the occurrence of the cyst was combined with the presence of an apical defect of the acrosome. From ultrastructural studies of spermatids the development of the cystic defect was found to have reached a rather advanced stage early in the acrosome-phase of the spermateliosis. As a whole the observations correspond very well with those made in connection with the socalled "SME"-defect first found in a Danish Landrace boar.

Acrosome↗
PubMed1976

[Results of television microscopy utilization in spermatology].

The use of television microscopy in insemination laboratories was tested by VEB Studio-technik on two insemination stations of the GDR. A transistorised remote-observation system is described as a tool providing a universal range of applications for long-time no-maintenance operation of selected microscopes. The system was found to add to the accuracy and objective value of optical microscopy for spermatological studies. TV microscopy also will improve job conditions for the personnel involved.

Animals↗
PubMed1976

Antibody-coated bacteria in the urine of preschool and school-aged girls with asymptomatic bacteriuria.

Urine samples from 3564 girls aged 2 to 13 years were screened for evidence of infection. Cultures were positive (bacteria count, more than 10(5)/ml) in 61 (1.7%) by the dipslide method and in 55 (1.5%) by standard culture techniques. In 13 (23.6%) of the 55, antibody-coated bacteria (ACB) were detected in the urine. The clinical, bacteriologic, radiologic and urinalysis findings in children with ACB were no different from those in children in whom the bacteria were not coated. Direct examination of uncentrifuged urine under high power revealed one or more bacteria per two high-power fields in 96% of infected urine samples and in only 7% of noninfected samples. Five or more leukocytes per high-power field in centrifuged urine were detected in 36.7% of infected urine samples but not in noninfected samples. The ACB test did not differentiate between asymptomatic bacteriuria with parenchymal scarring or vesicoureteral reflux or both and asymptomatic bacteriuria without these abnormalities.

Adolescent↗
PubMed1976

Lymphocyte locomotion. I. The initiation, velocity, pattern, and path of locomotion in vitro.

The locomotive behaviour of human lymphocytes in coverslip preparations of clotted autoplasma was studied at +37 degrees C. Lymphocytes isolated from peripheral blood or from the tonsils did not move prior to membrane activation by means of incubation with phytohemagglutinin (PHA). After PHA stimulation the locomotion of 19 lymphocytes was analysed by time-lapse fliming. The locomotion was random, as evidenced by a median locomotive index of 0.64 (Q1-Q3 0.04-0.75) and comparatively slow, median velocity 15 mum/min (Q1-Q3 12-18). The locomotion of 5 other lymphocytes was studied at high magnification. It is suggested that the characteristic polarity of wandering lymphocytes, indicating the direction of movement, can be utilized in the analysis of the lymphocyte traffic in tissue sections of post-capillary high-endothelium venules.

Cell Movement↗
PubMed1976

Lymphocyte locomotion. II. The lymphocyte traffic over the post-capillary venules analysed by phase contrast microscopy of thin sections of rat lymph nodes.

Thin sections of lymph nodes from 14 rats were examined by phase contrast microscopy as regards direction of lymphoctes with amoeboid movement configuration (AMC) relative to the basement membrane of post-capillary high-endothelium venules (HE-cenules). Out of 118 lymphocytes with AMC, 82 appeared to be on theyr way into the venule from the lymph node parenchyma. This observation suggests that the lymphocyte traffic over the HE-venules is bi-directional, with the main migratory stream of lymphocytes from the lymph node parenchyma into the post-capillary venules.

Animals↗
PubMed1976

[Isolation and function of platelets. I. Platelet rich plasma. Comparison between 2 methods: gel filtration and albumin density gradient centrifugation. II. A new method using total blood: metrizamide gradient centrifugation].

Human platelets separated from platelet rich plasma (PRP) by two different methods: gel filtraton and centrifugation on albumin gradient have been compared for yield, cellular and protein contamination, ultra-structure, platelet populations, shape change, aggregability and functional preservation. A new method for the separation of platelets from total blood on metrizamide gradients has been established. This technique is rapid and easy; it avoids the initial centrifugation of the PRP where about 30% of the platelets are lost and needs of blood 5 to 10 ml of blood.

Blood Platelets↗
PubMed1976

[Cytological studies in pulmonary pathology].

Cytological investigations of the bronchial secretion and sputum in particular have acquired in recent years a great practical significance in pulmonary pathology. It is recommended to use cytodiagnosis along with prophylactic X-ray examinations of the population to detect pulmonary pathology, in particular among individuals with a higher risk of developing cancer. A substantiated opinion is put forward that cytodiagnosis should precede examinations of patients with clinico-roentgenologically confirmed changes in the lungs.

Adenoma↗