Biomedical subjects

K Spanel-Borowski

Publications and source records attributed to K Spanel-Borowski.

67 records · Page 4Linked to original sources

PubMed1984

Cell proliferation in the principal target organs of the dog (beagle) ovary during various periods of the estrous cycle.

Cell proliferation in the principal target organs of the ovary was studied in 7 beagle dogs during proestrus, early estrus, secretory and regressive metestrus. Pulse labelling with (3H)-thymidine and autoradiography were applied and labelling indices were determined. Organs with squamous and with glandular epithelium except the mammary gland showed a proliferation peak during early proestrus, the incidence of labelling being higher in organs with squamous epithelium. During early proestrus the intensity of labelling decreased in organs with squamous epithelium in the following order: vulva, vagina, portio vaginalis, and portio supravaginalis. At this time cell replication was higher in the superficial glands of the cervix and corpus uteri as well as the circular layer of the myometrium compared with values from the basal glands or the longitudinal layer. The steepest decline of the proliferative activity occurred between the proestrous period. While some labelled cells were observed during secretory metestrus, labelling was almost absent during regressive metestrus. By contrast, the mammary gland began to develop at the periovulatory period and was at the height of its proliferative activity during secretory metestrus. It is concluded for species with a long estrous cycle that: (1) the rate of cell replication in the vulva, vagina, uterus and oviduct is at its peak at the beginning of the estrous cycle and declines during proestrus; (2) as compared to observations in species with short estrous cycles, cell proliferation is very low during metestrus.

Animals↗

PubMed1983

Follicular growth and intraovarian and extraovarian oocyte release after daily injections of melatonin and 6-chloro-melatonin in the Syrian hamster.

Groups of adult female Syrian hamsters (Mesocricetus auratus) were injected daily at 17:00 hr with 2.5, 15, or 25 micrograms of melatonin (Mel) or 6-chloro-melatonin (Cl-Mel) for 12 weeks. An ovary from each animal was completely serially sectioned for light microscopic investigation. Judging from the presence of corpora lutea, there were some animals in each group that continued to cycle, although the postestrous, white mucous discharge had disappeared. Noncycling animals were most often found in the 25-micrograms group of Cl-Mel. Only uterine weights of noncycling animals treated with either 25 or 15 micrograms of Mel or Cl-Mel were statistically significantly depressed versus controls. Cl-Mel (25 micrograms) significantly suppressed the total number and size of antral follicles (P less than 0.05). Follicular ruptures with incomplete or complete release of the oocyte out of the follicular compartment were observed. The oocyte release occurred either into the ovary ("intraovarian oocyte release: IOR") or outside of the ovary ("extraovarian oocyte release: EOR"). Compared with controls, the total number of IOR was increased in all experimental groups with the exception of the 2.5-micrograms group of Cl-Mel. IOR appeared in both preantral and antral follicles, and often IOR was complete. In controls, only preantral follicles were involved in IOR; these were primarily incomplete ones. IOR was seen in cycling and noncycling animals. By contrast, EOR was exclusively observed in noncycling hamsters. It is concluded that the cessation of postestrous, white mucous discharge is not necessarily an index for a halt in cyclic ovarian function. Injections of 25 micrograms of Cl-Mel are more effective than 25 micrograms of Mel in suppressing ovarian function. Both Mel and Cl-Mel increase the frequency of IOR. Finally, noncycling hamsters show EOR that is regarded as an abnormal ovulation.

Animals↗

PubMed1983

Morphological and morphometric changes in the ovaries of white-footed mice (Peromyscus leucopus) following exposure to long or short photoperiod.

Two experiments were carried out with a total of 36 white-footed mice (Peromyscus leucopus) exposed to either long (LP) or short (SP) photoperiod for six weeks. Ovaries and uteri were weighed. Serial sections of the ovaries were processed for light microscopy. The total number of the interstitial gland cells, preantral and antral follicles with early and advanced stages of atresia as well as corpora lutea, was determined. Uteri from LP mice weighed significantly more than those from SP mice in both experiments. In contrast, the weight of ovaries from LP and SP animals only differed significantly in one experiment; this experiment also produced no obvious changes in the total number of corpora lutea. While interstitial gland cells of LP ovaries were hypertrophic and appeared mature, the interstitial gland cells of SP ovaries were of the degenerating cell type. The total number of follicles as well as their mean follicular diameters were higher in LP animals in comparison with SP animals. In addition, the percentage of antral follicles were increased and there were fewer signs of advanced stages of atresia in the LP group. It is suggested that the changes of the interstitial gland cell morphology combined with alterations of follicular growth during LP or SP appear to support intensified follicular growth.

Animals↗

PubMed1983

A possible mechanism of rapid luteolysis in white-footed mice, Peromyscus leucopus.

Adult female white-footed mice, Peromyscus leucopus, were exposed to long (LP) or short (SP) photoperiods for 6 weeks (experiment I). Another group of animals was kept for 6 weeks in SP, then injected SC with 30 micrograms prolactin twice daily for 2, 3, 4, or 6 days (experiment II). Ovaries from the mice in both experiments were weighed and serially sectioned for light microscopic examination of regressing corpora lutea. In experiment I, it was observed that vessels supporting corpora lutea were dilated, and that their endothelium was either undergoing necrosis or it was missing. Pronounced changes of luteal capillaries led to rupture and intraluteal hemorrhage, thus opening the capillary bed. Regressing luteal cells became segregated and seemed to invade the vascular system passively. They were seen as luteal cell thrombi in medullary veins. This luteolytic course termed "rapid luteolysis" was most apparent in SP ovaries. It differed from "retarded luteolysis," which represents the well-established luteolytic model of auto- and heterophagocytosis. In experiment II, there was a statistically significant decrease in ovarian weight 4 days after prolactin treatment in comparison with saline-treated controls. At the light microscopic level, signs of both rapid and retarded luteolysis were present, but not intensified. It is concluded: (1) The concept of rapid luteolysis represents a reasonable working hypothesis. (2) Prolactin, though luteolytic at the macroscopic level, failed to produce evidence of increased rapid or retarded luteolysis at the light microscopic level.

Animals↗

PubMed1982

Preantral intra-ovarian oocyte release in the white-footed mouse, Peromyscus leucopus.

Adult white-footed mice, Peromyscus leucopus, were kept either in long photoperiod (LP; LD 16:8) or in short photoperiod (SP; LD 8:16) for six weeks. Ovaries were serially sectioned and examined histologically. Preantral follicles were observed to release their oocyte into the ovarian stroma. This phenomenon is termed "preantral intra-ovarian oocyte release (PIOR)". The first step in PIOR appeared to be the interruption of the basal membrane and the thecal layer. PIOR was considered incomplete when the oocyte was retained in the follicular compartment. PIOR was complete when granulosa cells were seen to be herniated and the oocyte released either into the interstitial cortical tissue or into a corpus luteum. During incomplete PIOR signs of atresia were increased, whereas during complete PIOR they were decreased. Resumption of meiosis was not seen. PIOR was observed in 19.5% of the ovaries after LP and in 18.8% of the ovaries after SP. PIOR is regarded as a sign of follicular atresia.

Animals↗

PubMed1982

Occurrence of preantral intra-ovarian oocyte release in the rat and the Syrian hamster (Mesocricetus auratus).

Serial sections of 62 rat ovaries and 66 ovaries from Syrian hamsters (Mesocricetus auratus) have been examined by light microscopy. The relative and absolute percentage of preantral intra-ovarian oocyte release (PIOR) was recorded. PIOR was incomplete when the rupture of the basal membrane was not followed by the release of the oocyte from its preantral follicle into the ovarian stroma; conversely, a PIOR was regarded to be complete if the oocyte was released from the preantral follicle into the adjacent stroma. PIOR occurred in 23% of rat ovaries and in 32% of hamster ovaries; meiosis was not resumed. In rat ovaries the frequency of complete PIOR was 71%; the oocyte disappeared quickly after its release and herniated granulosa cells could invade capillaries. By contrast, incomplete PIOR was prevalent in hamster ovaries (67%); oocytes survived in the interstitial cortical tissue after the disappearance of their granulosa and theca cells ("free oocytes"). It is concluded that PIOR reflects the onset of follicular atresia and that different local factors are probably responsible for species differences.

Animals↗

PubMed1982

Short- and long-term response of the adult dog ovary after 1200 R whole-body X-irradiation and transfusion of mononuclear leukocytes.

The effect of 1200 R whole-body X-irradiation after transfusion of mononuclear blood cells was investigated in 34 dog ovaries (beagle) for 6-1460 days after irradiation. Morphological observations suggest that gonadal and extragonadal function regenerated after irradiation. Follicular growth started 60 days after irradiation. The time required for follicular maturation was inferred to be about 110 days and the time of first ovulation about 170 days. Graafian follicles and corpora lutea were found 2, 3 and 4 years later. A pregnancy occurred 2 years after irradiation. Larger, growing and vesicular follicles were primarily affected by irradiation-induced atresia with damage of the granulosa. Oocytes appeared to be normal, even without the supporting granulosa cells ('naked oocytes'). The interstitial cortical tissue of the ovaries reacted in two ways. Either, it remained inactive (radiation effect I) or it showed the endocrine structure of mature interstitial gland cells (radiation effect II). Microadenomata were observed 195 days after irradiation.

Animals↗

PubMed1981

Aspects of cellular proliferation during follicular atresia in the dog ovary.

Autoradiography after pulse labelling with [3H] thymidine was applied to investigate the proliferation processes in the granulosa and theca related to follicular atresia of the dog ovary during metestrus. The number of proliferating cells depends on the follicle type and its atretic stage. There is less proliferation in smaller secondary follicles than either in larger ones or tertiary follicles. While in early atresia tertiary follicles show the highest labelling indices, in advanced atresia the largest secondary follicles are those with the highest values. For each follicle type a decline in the labelling indices can be observed from early to terminal atresia. Tertiary follicles show a precipitous decrease in the labelling index between early and advanced atresia. There is a continuous gradient of proliferation from the center of the follicle over the peripheral granulosa to the theca. In tertiary follicles, an inverse correlation between labelling and necrosis of granulosa cells can be observed.

Animals↗

PubMed1981

Morphological investigations on follicular atresia in canine ovaries.

Morphologically, canine ovaries show two types of regression pattern in secondary follicles. In type A necrotic changes of the oocytes and the zona pellucida dominate, whereas in type B degeneration, necrobiosis and necrosis of the granulosa prevail. The atretic course of type B regression results in a pseudoantrum and leads, by pseudogrowth, to a structure imitating tertiary follicles. In both type A and type B regression, four consecutive stages of atresia are distinguished by light- and electron microscopy. True teritary follicles display only one regression pattern which resembles type B of secondary follicles. Early, advanced, late, and terminal stages of atresia are again described.

Animals↗

PubMed1976

[Experimental candida vaginitis in the mouse (author's transl)].

Manifest Candida albicans infection of the vagina of mice was achieved only after oestrogen treatment. Histologically, different phases of vaginal candidiasis could be observed: the mycotic infection began with a massive colonization of Candida albicans in the horny layers of the vaginal epithelium and an early immigration of granulocytes. Abscess-like changes followed when high number of yeast cells were used for infection. One to two weeks after onset the inflammatory changes decreased and fungi were no longer identifiable in epithelial micro-abscesses by the methods employed. In contrast, yeast cells could be detected within the vaginal skin exhibiting weak inflammatory lesions up to the 57th day. Chemotactic studies showed that the fungi considerably stimulated the migration of mouse granulocytes in the presence of serum. Since mannan isolated from the Candida cell wall also possesses strong chemotactic activity, certain components of the fungal cell wall may play a pathogenic role in Candida colpitis.

Animals↗

PubMedDate not supplied

Classification of a collection of malformed human hearts: practical experience in the use of sequential segmental analysis.

The inauguration of Sequential Segmental Analysis (SSA) a few decades ago provides basic conditions to establish a universally applicable classification system for cardiac malformations. To gain practical experience, we used this method to classify a collection of 292 congenitally malformed human hearts. Our aims were to determine advantages and problems of the SSA and to make recommendations for a better practical usability and documentation. SSA is an appropriate instrument for the description of complex cardiac malformations because it is a logical step-by-step approach based on the heart morphology. The method optimizes the diagnosis of different malformed hearts. However, there are some disadvantages of SSA concerning terminology, localization of simple septal defects and exact topographic description of heart structures. For these reasons, we recommend a graphic description of the malformed heart using symbols based on the SSA. The most important prerequisite for an interdisciplinary acceptable classification system of cardiac malformations is to include morphological as well as functional aspects of the hearts.

Adolescent↗

PubMedDate not supplied

Albumin localization in the testis of adult golden hamsters by use of immunohistochemistry.

There is an increasing interest in different biochemical roles of albumin (Alb) in respect to testicular function. For this reason, Alb was localized by the peroxidase-antiperoxidase technique in the testis of adult golden hamsters. A strong Alb immunoreactivity occurred in the interstitial space and on the surface of Leydig cells. A few Sertoli cells showed a strong Alb response under the appearance of so-called leakages traversing Sertoli-Sertoli cell junctions. Spermatogonia reacted strongly, while spermatids and sperms showed rather a mild, or moderate response. Spermatocytes remained unstained. When similar maturation stages of seminiferous tubules were compared, the number of reacting cells varied strikingly. Our results support the assumption that Alb or a protein with an Alb-like immunoreactivity exerts diverse functions of the testis.

Albumins↗

PubMedDate not supplied

Microvascular endothelial cells differ in their basal and tumour necrosis factor-alpha-regulated expression of adhesion molecules and cytokines.

We recently located a rare cytokeratin-positive (CK+) type of microvascular endothelial cell (MVEC) in the corpus luteum and aorta. Bovine corpus luteum MVEC are known to be involved in the cyclic accumulation of eosinophils and macrophages. Since leukocyte migration is specifically mediated by adhesion molecules and the release of cytokines, we compared the expression of these factors in basal and TNF-alpha-stimulated CK+ MVEC and in common cytokeratin-negative (CK-) MVEC in order to obtain an initial insight into the functional capacities of CK+ MVEC. CK- MVEC revealed significantly higher basal RANTES mRNA expression than CK+ MVEC, and TNF- alpha up-regulated RANTES mRNA in both types of MVEC. Only resting and stimulated CK- MVEC expressed granulocyte-macrophage colony-stimulating factor mRNA. Both MVEC types expressed monocyte colony-stimulating factor mRNA, but remained negative for eotaxin and interleukin (IL)-5 mRNA even after stimulation. Resting CK+ MVEC were positive for CD29, CD31, CD49a and CD49e, but expressed most of these antigens at a significantly lower density than did CK- MVEC. In contrast to CK- MVEC, CK+ MVEC failed to express CD49b or MHC class II. The activation of CK+ MVEC with TNF-alpha induced the expression of CD62P, but not of CD49b or MHC class II. In summary, phenotypically variable MVEC derived from the microvascular bed of one organ differ in their TNF-alpha-regulated expression of cytokine mRNA and adhesion molecules. Morphological heterogeneity is related to a particular specialisation of functional MVEC.

Animals↗