Expressions and localizations of Bax/Bcl-2 proteins during metamorphosis of Pelophylax ridibundus.

Bcl-2 and Bax proteins are expressed in cells of the tails of Pelophylax ridibundus larvae. We investigated the levels of these proteins in tails undergoing apoptosis. Apoptotic cells were observed in the epidermis, muscle and notochord of tails of different lengths. The apoptotic cells in epidermis exhibited the typical features of apoptosis. Amorphous masses and irregularities in striated muscle tissue undergoing apoptosis and apoptotic remnants in the notochord also were observed. In general, Bax staining in the epidermis, subepidermal fibroblast layer, muscle and notochord cells increased, while Bcl-2 staining decreased as the tail regressed. Our results suggest that during tail regression due to metamorphosis, Bcl-2 and Bax proteins play key roles in the apoptosis of tail epidermis, subepidermal fibroblast layer, muscle and notochord cells.

Expression and localisation of Bcl-2 and Bax proteins in developing rat ovary.

Bcl-2 and Bax proteins localised mainly in granulosa cells. Primordial and primary follicles of new born rat ovary showed an intensive nuclear staining for Bax but faint staining for Bcl-2. In terms of staining intensity, no remarkable difference was observed within the same stage of developing follicle. Compared to new born rats, granulosa cells of adult and one month old rat ovary showed an increased staining both for Bcl-2 and Bax proteins. No staining was observed in primordial follicles of one month old and adult rats. However, granulosa cells of primary follicles, granulosa cells and theca cells in tertiary follicles of adult rat ovary also showed a strong staining for Bcl-2 and Bax proteins. Oocytes of follicles from different developmental stages revealed an apparent staining both for Bcl-2 and Bax proteins. However, in the more mature follicles oocytes stained more intensively. In developing corpus luteum a remarkable staining was observed for Bax. However, the staining was more prominent in regressing corpus luteum. Contrary to this, Bcl-2 stained the luteal cells in developing corpus luteum strongly, while in the fully developed corpus luteum no staining for Bcl-2 was observed. In conclusion, there was an apparent relation between the expression of the apoptosis regulating protein Bcl-2 and Bax and follicular development. Thus, during the follicular development Bcl-2 and Bax may be involved in granulosa cell demise in rat ovary. Furthermore, increased levels of Bax and decreased levels of Bcl-2 in the fully developed corpus luteum suggest that Bax plays a role in apoptosis of luteal cells in rat ovary.

Matrix metalloproteinase-9 in broncho-alveolar lavage fluid of patients with non-small cell lung cancer.

AIM: To evaluate concentration of MMP-9 in blood plasma and broncho-alveolar lavage fluid (BALF) from patients with non-small cell lung cancer (NSCLC). METHODS: Blood plasma from 40 NSCLC patients and 40 healthy donors was collected and concentrations of blood plasma and BALF MMP-9 were measured using ELISA. Correlation between MMP-9 level and gender, histological type of tumor and stage of disease was analyzed. RESULTS: Levels of blood plasma MMP-9 were significantly higher in NSCLC patients (p < 0.0001) then in control group, and were especially high in patients with stage IV of disease (stage I vs stage IV - p < 0.005, stage II vs stage IV - p < 0.01, stage III vs stage IV - p < 0.01). Also, stage IV of NSCLC was characterized by the highest level of BALF MMP-9 (stage I vs stage IV - p < 0.002, stage II vs stage IV p < 0.002, and stage III vs stage IV p < 0.007). Correlation between blood plasma and BALF MMP-9 levels and gender or histological type of tumor was insignificant. CONCLUSION: Our data revealed significant correlation between tumor stage and BALF and plasma MMP-9 levels in NSCLC patients.

Effects of constant lightness, darkness and parachlorophenylalanine treatment on tail regeneration in the lizard Ophisops elegans macrodactylus: macroscopic, biochemical and histological changes.

A better understanding of regenerative growth is very important for the development of new potential strategies. Recently, the pineal secretory product melatonin was shown to stimulate the regeneration process. In this study, we carried out an experimental investigation of tail regeneration in young adult lizards, Ophisops elegans macrodactylus Berthold, 1842, addressing the role of melatonin on the regeneration process. Lizards were divided into three groups: constant light-exposed control group (n = 13), constant dark-exposed group (n = 15) and parachlorophenylalanine (p-CPA) treatment group exposed to constant light (n = 15). Using a tail autotomy procedure, the effects of p-CPA treatment on connective tissue together with neural tissue and vascular tissue in regenerating tail in lizards were investigated. p-CPA (400 microg/kg body mass) was injected from day 0 to 30 days after autotomy. p-CPA treatment produced a significant increase in the length of the regenerated tail compared with light-exposed control and dark-exposed lizards. Total collagen content was found to be higher in p-CPA-treated animals in comparison with other groups. Histologically, a higher percentage of connective tissue and vascular tissue and a lower percentage of neural tissue were found in the regenerated tails of the p-CPA-treated lizards. Importantly, the percentage of neural tissue in lizards in the dark-exposed animals was higher than that in animals of both light-exposed and p-CPA treatment groups. Thus, it is clear that p-CPA has a stimulatory influence on fibroblast collagen production and vascularization of the regenerated tail in the lizards. Furthermore, it seems that the neural regeneration process was markedly enhanced in lizards exposed to continuous darkness. Based on the results of our study, it is suggested that melatonin may be an active factor that speeds up the rate of tail regeneration in lacertilians.

Antioxidant activity of seminal plasma in fertile and infertile men.

This study was conducted to evaluate and compare the total antioxidant capacity among fertile and infertile men. Thirty infertile patients and 20 fertility-proven healthy donors with normal sperm analysis were included in the study. Total antioxidant capacity, zinc and fructose levels of seminal plasma, and various sperm parameters were compared among fertile controls and idiopathic infertility patients prospectively. The mean antioxidant capacity of fertile controls (2.02 +/- 0.16 mmol/L) was significantly higher than that of the infertile patients group (1.78 +/- 0.23 mmol/L) (p < .01). Furthermore, asthenozoospermic and asthenoteratozoospermic groups had significantly lower mean antioxidant values (1.73 +/- 0.11 and 1.64 +/- 0.13, respectively) when compared to fertile control group (p < .01). The mean fructose level was significantly lower in the fertile control group and mean zinc level was significantly lower in the entire infertile group. On the other hand, antioxidant capacity is positively correlated to sperm motility (p = .001). Decreased antioxidant capacity was associated with impaired sperm function as a result of either increased ROS production or insufficient antioxidant capacity.

Effects of a DNA demethylating agent--5-azacytidine--on testicular morphology during mouse embryo development.

DNA methylation is an epigenetical mechanism that plays crucial roles in cellular differentiation and tissue development in embryogenesis. The aim of the present study was to determine the effects of a demethylating agent, 5-azacytidine, on testicular development during embryonal life in mouse. Ten pregnant mice were administered 5-azacytidine (5-azaC) (i.p. 2 mg/kg of agent dissolved in 0.1 mg/ml PBS) during 8th (Group 1), 11th (Group 2), 14th (Group 3) and 18th (Group 4) days of pregnancy periods and male siblings of these animals were obtained (experimental groups) whereas the control group animals received no treatment and siblings of this group were also obtained. Testicular tissues from all groups were taken 20 days after birth and examined at the light and electron microscopical levels. All pregnancies were terminated in Group 1 animals, therefore no observations could be done in this group. While Group 2 and 3 siblings showed distinctive kongenital abnormalities such as; anancephaly, growth failure, cleft palate, extremity abnormalities, supernumerary ribs and whirled shaped-tails, no such abnormalities were observed in Group 4 when compared to the control group. Microscopical examination of testicular tissues in groups 2 and 3 demonstrated cellular disintegration of spermatocytes in seminiferous tubules. In addition, cytoplasmic vacuoles and thickening of the basement membrane were also evident in both groups 2 and 3. Apoptotic-like cells were seen especially in group 2 and rarely in group 3. There were no structural alterations in group 4 animals, except a decreased number of spermatocytes in seminiferous tubules when compared to the control group, possibly indicating the completion of embryogenesis in this group. In conclusion, it could be suggested that the demethylating agent 5-azacytidine may trigger an unknown gene reactivation during early embryogenesis possibly affecting the cell and tissue differentiation in developing mammalian embryos.

Comparison of the effects of vasectomy and experimental cryptorchidism in rats: I. Testicular histology.

The effects of cryptorchidism, one of the most important congenital malformations resulting with the defects in testicular structure thus infertility, is the best known subject in male reproduction. Those best known effects make the usage of cryptorchidism as a second control criteria when the effects of other male infertility reasons are attempted to be determined. Therefore the persistency or reversibility of the effects of vasectomy on testicular structure have been compared to the testicular features following experimental cryptorchidism and to the control group findings. To do this, rats were divided into 3 groups. While the control group animals were sham operated, the experimental group animals were undergone either vasectomy or experimental cryptorchidism procedures. Testicular histology of the control and experimental groups was determined using convenient staining methods at the light microscopical level. The comparison of the findings from the control and experimental groups showed that the testicular features of the vasectomized group were similar to those seen in the control group in contrast to the experimental cryptorchidism group which had irreversible testicular alterations. Results of the present study indicated the convenience of the usage of vasectomy in male contraception.

Blastocyst implantation in rats: a morphological approach.

Very complex cellular events take place at the morphological and molecular levels both in the maternal and embryonic sites during blastocyst implantation. Although the morphological alterations in the gestational stages of the implantation site are well-known, mechanisms of the interaction between blastocyst and endometrial epithelium (apposition and adhesion stages) and penetration of the blastocyst into the endometrium have not yet been fully described. Therefore the present study was designed to determine these events morphologically throughout the implantational stages. To do this the endometrial tissues containing implantation sites from pregnant rats were taken 5 and 8 days after fertilization. In addition, non-pregnant rat endometrial tissues were also obtained in order to use as control. Tissues were processed for light and electron microscopy. Semi-thin and ultra-thin sections were stained using appropriate staining methods, and were evaluated under light and electron microscope. In the present study, interaction between trophoblast and luminal epithelium, penetration of the blastocyst into the endometrium, differentiation of germinal layers in the blastocyst and tissue alterations such as decidualization in the maternal site have been demonstrated morphologically. In conclusion, while blastocyst was implanted into the endometrium, distinct morphological changes occurred both in maternal and embryonic sites. The following stages of implantation were the development of germinal layers in the embryo and morphological changes in the maternal site leading to the placentation.

Comparison of the effects of vasectomy and experimental cryptorchidism in rats: II. Epididymal histology.

Vasectomy is a male contraception method that its side effects and reversibility rate are still controversial. Effects of vasectomy on epididymal morphology and function, which plays a crucial role in sperm maturation and storage, have not yet fully described. Therefore the present study was planned to find out the effects of vasectomy on epididymal structure, and comparisons of these effects were also made with the effects of a persistent infertility model, experimental cryptorchidism. To do this, 15 male Swiss albino rats were divided into 3 groups. While 5 animals were sham-operated, the rest were undergone either vasectomy (5 rats) or experimental cryptorchidism (5 rats) procedures. Epididymal tissue samples were collected prepared for light microscopy. Tissue sections were stained using appropriate staining techniques and evaluated under the light microscope. While there were distinct alterations in the epididymal morphology following experimental cryptorchidism, vasectomized rat epididymal features seemed similar to those seen in the sham-operated group. In conclusion, it could be suggested that the vasectomy might be a convenient method for male contraception.