Effect of Follicle Size on In Vitro Maturation of Pre-Pubertal Porcine Cumulus Oocyte Complexes.

Very small follicles (<3.0 mm diameter) are over-represented on the surface of ovaries of non-cycling pigs, and the oocytes collected from these follicles generally have reduced developmental competence in vitro. This study examined the effect of follicle size on the nuclear maturation (n = 608), the potential of parthenogenetic activation (n = 243) and the cyclic AMP (cAMP) content of pre-pubertal porcine oocytes (n = 480). In addition, the influence of follicle size on steroid hormone synthesis was analysed. Cumulus oocyte complexes (COCs) flushed from small (2.5-4.0 mm) or large (4.5-6.0 mm) ovarian follicles were cultured for 0, 28 and 46 h. After 46 h of IVM, a greater proportion of oocytes from 4.5- to 6.0-mm follicles reach metaphase II (MII) compared with those from follicles with 2.5-4.0 mm of diameter (96.1 vs 77.0%, respectively; p < 0.001). Parthenogenetic activation of oocytes from large follicles produced higher developmental rates than oocytes from large follicles (p < 0.05). At 28 h, the IVM medium with oocytes from large follicles contained significantly more 17ß-oestradiol (E2 ) than the medium with oocytes from small follicles (5.55 vs 3.45 ng/ml, respectively; p < 0.05) and at 46 h, the medium with oocytes from small follicles contained significantly more progesterone (P4 ) than the medium with oocytes from large follicles (276.7 vs 108.2 ng/ml, respectively, p < 0.05). Porcine oocytes from large follicles have higher nuclear and cytoplasmic maturation capacities, but the differences did not appear to be cAMP-mediated. Our findings also suggest that COCs from small follicles undergo more intensive luteinization than COCs from large follicles. The results show that oocytes from follicles with a diameter greater than 4.0 mm are more suitable for in vitro studies.

Bone morphogenetic protein-6 (BMP-6): mRNA expression and effect on steroidogenesis during in vitro maturation of porcine cumulus oocyte complexes.

Oocyte secreted factors (OSFs) have emerged as important factors for follicular development. The present study investigated the effect of the potential OSF bone morphogenic protein (BMP)-6 on steroidogenesis in porcine cumulus oocyte complexes during in vitro maturation. Cumulus oocyte complexes (COCs), cumulus complexes (CCs) without oocytes and CCs with supplemented BMP-6 were cultured for 0, 5, 26 or 46 h. BMP-6 transcripts were detected in oocytes and cumulus cells at all time points. In both cell types the mRNA expression was most intense after 5h, and decreased during further maturation. After 26 and 46 h of culture, CCs secreted significantly less 17ß-estradiol than COCs. This effect was reversed by adding BMP-6 to CCs cultures. In addition, a down-regulation of Cyp19A1, the rate-limiting enzyme of 17ß-estradiol synthesis, was detected in CC cultures after 5h. As seen for 17ß-estradiol secretion, the addition of BMP-6 caused a significant increase in Cyp19A1 mRNA levels after 5, 26 and 46 h of culture. Progesterone secretion and transcripts of steroidogenic marker proteins StAR and 3ß-HSD were not affected considerably by oocyte removal or addition of BMP-6. Furthermore, BMP-6 did not affect the activity of the mitogen-activated protein kinase. The results indicated that BMP-6 is a potential OSF and is involved in the prevention of premature luteinisation in cumulus cells via enhancing 17ß-estradiol synthesis.

Steroidogenesis and the influence of MAPK activity during in vitro maturation of porcine cumulus oocyte complexes.

The aim of this study was to investigate steroidogenesis within porcine cumulus oocyte complexes during in vitro maturation and to examine the possible influence of the mitogen-activated protein kinase (MAPK). Porcine cumulus oocyte complexes were matured in vitro with and without the MAPK kinase inhibitor U0126 for 0, 5, 26 and 46 h. The 17ß-estradiol and progesterone concentration in the culture medium were then determined. In addition, the mRNA levels of StAR, Cyp11A1, 3ß-HSD and Cyp19A1 in cumulus cells were analysed by RT-PCR. Using an immunoblot, the MAPK phosphorylation in cumulus cells and oocytes was examined. During the first 26 h of in vitro maturation, 17ß-estradiol secretion was predominant, whereas, after a culture period of 46 h, the progesterone secretion decreased conspicuously. Under the influence of U0126, the secretion of 17ß-estradiol increased progressively during the complete maturation period, while progesterone secretion was completely inhibited. The mRNA levels of StAR and Cyp11A1 were not altered by U0126; however, corresponding to the hormone secretion, the gene expression of Cyp19A1 was up-regulated and the expression of 3ß-HSD down-regulated. The results suggested an influence of the MAPK on steroidogenesis in cumulus cells comparable to a luteinization factor. Hormone synthesis in cumulus cells during oocyte maturation seems to be regulated by altering expression of Cyp19A1 and 3ß-HSD.

[Detection of lung fibrosis in a polyclinic department for lung diseases and tuberculosis]. / Erfassung von Lungenfibrosen in einer Poliklinischen Abteilung für Lungenkrankheiten und Tuberkulose.

34 persons with pulmonary fibrosis found by the Chest Clinic were evaluated. Nearly half of all patients were sent by other physicians. Dyspnea and bronchitis are of the first place in the range of frequency of complaints. In some cases the troubles were existing for 20 years. In the main cause of delay was diagnosis' failing inspite of suspicious x-ray picture and troubles mentioned above.

[Detections of cases of bronchial carcinoma by reason of complaints and analysis of the times of delay (author's transl)]. / Erfassung von Fällen mit Bronchialkarzinom auf Grund von Beschwerden und Analyse der hierbei aufgetretenen Verschleppungszeiten.

52 persons with bronchial carcinoma found by reason of complaints by the Chest Clinic were critically evaluated. Cough, hemoptysis and thoracic pain are of the first place in the range of frequency of complaints caused by the tumour. The time elapsing between the onset of the troubles to the first medical visit and from this consultation to the hospital admission was analysed. The complaints were existing more than 4 weeks in nearly half of all patient before they went to a physician. The causes of delay are discussed. The necessity of immediate x-ray examination of persons in the age endangered by cancer is emphasized if complaints suspicious to carcinoma especially the three symptoms mentioned above persisting more than three weeks inspite of treatment. For that purpose the personal conversation with persons from risk groups and continuous cooperation with other physicians in the territory are important.