Synthetic hybrids of six yeast species.

Allopolyploidy generates diversity by increasing the number of copies and sources of chromosomes. Many of the best-known evolutionary radiations, crops, and industrial organisms are ancient or recent allopolyploids. Allopolyploidy promotes differentiation and facilitates adaptation to new environments, but the tools to test its limits are lacking. Here we develop an iterative method of Hybrid Production (iHyPr) to combine the genomes of multiple budding yeast species, generating Saccharomyces allopolyploids of at least six species. When making synthetic hybrids, chromosomal instability and cell size increase dramatically as additional copies of the genome are added. The six-species hybrids initially grow slowly, but they rapidly regain fitness and adapt, even as they retain traits from multiple species. These new synthetic yeast hybrids and the iHyPr method have potential applications for the study of polyploidy, genome stability, chromosome segregation, and bioenergy.

Heat shock protein 70 and sex steroid receptors in the follicular structures of induced ovarian cysts.

The purpose of this study was to estimate the expression and relative amounts of estrogen (ER) and progesterone receptors (PR) and their isoforms as well as heat shock protein 70 (HSP70) in ovaries of rats with induced cystic ovarian disease (COD). Primary, secondary, tertiary, atretic and cystic follicles were evaluated by immunohistochemistry and total ovarian proteins were analyzed by Western blot. In the granulosa layer, growing and cystic follicles in the treated group have a higher expression of ERalpha than growing follicles of control individuals. In the theca interna layer, tertiary follicles presented a significantly higher expression of ERalpha in the treated group. An increase in total ERalpha protein was detected in the treated group. Granulosa cells of all growing, atretic and cystic follicles show a lower expression of ERbeta in animals with COD, and the total protein expression of ERbeta was lower in this group. The expression of PR was lower in the granulosa cell layer of tertiary and cystic follicles in treated animals, and theca interna layer had less intense immunostaining in this group. Although there were no differences in the expression of PR-B by Western blotting, the expression of PR-A was higher and the expression of PR-C was smaller in the treated group. An intense HSP70 immunostaining was observed in the cells of cystic follicles. By Western blotting, higher protein expression of HSP70 was detected in the ovarian samples of the control group than those of the treated ones. Ovaries of animals with COD exhibited an altered steroid receptor expression and subtype balance as compared with control animals, and an increase in HSP70 immunoexpression.

["Free" iron, transferrin and ferritin levels in serum and their relation with severe malnutrition]. / Hierro libre, transferrina y ferritina séricas en desnutrición aguda grave.

INTRODUCTION: "Free" serum iron has been associated with the development of edema in Kwashiorkor-type severe acute malnutrition. MATERIAL AND METHODS: A descriptive, cross sectional study was performed. Twenty-four children with edematous malnutrition, 22 with marasmus and 20 without malnutrition were compared. "Free" iron, transferrin, saturation index and attachment capacity of iron, ferritin, total protein, albumin, total iron, and C-reactive protein (CRP) were determined in serum. RESULTS: A significant difference was found between malnourished children with "free" serum iron and the control group in which "free" iron was not found. However, no significant differences were found in "free" serum iron levels between marasmatic and edematous children. Transferrin was negatively correlated with "free" iron (r=-0.519; p=0.000). Total proteins, albumin and transferrin were all significantly lower in children with edema than in those with marasmus. A low transferrin level and a high saturation index could be used to estimate the probability of edema in 67.5% of cases (p=0.001). CONCLUSIONS: Severe acute malnutrition was associated with the presence of "free" serum iron both in children with marasmus and in those with edema. "Free" iron does not explain the presence of edema but, as with severe hypoalbuminemia, the concurrence of a low transferrin level and a high saturation index may contribute to the etiology of edema.

The role of ACTH in the pathogenesis of polycystic ovarian syndrome in rats: hormonal profiles and ovarian morphology.

Numerous hypotheses have been proposed about the pathogenesis of the polycystic ovarian syndrome (PCOS). However, hormonal control of persistent follicles has not been established. The objective of the present study was to compare the follicular structure and hormonal profiles of rats treated with the adrenocorticotrophic hormone (ACTH) with two experimental models of PCOS. ACTH-treated animals were compared with those exposed to continuous light, those treated with estradiol valerate, and with control (in proestrous and diestrous). Serum hormone levels, histomorphometrical changes, and immunoexpression of vimentin, cytokeratins, cadherins, and proliferating cell nuclear antigen (PCNA) were examined. Treatment with ACTH resulted in an elevation of corticosterone secretion with LH reduction but without changes in ovarian morphology. Although stress (or ACTH) stimulation may be only one of pathophysiological mechanisms involved in follicular cyst pathogenesis in other species, we do not have important evidence to suppose that this would happen in rats.

A prospective comparison of the impact of uterine artery embolization, myomectomy, and hysterectomy on ovarian function.

PURPOSE: To prospectively compare uterine artery embolization (UAE) versus myomectomy and hysterectomy with regard to ovarian function as measured by postprocedure follicle-stimulating hormone (FSH) levels and symptoms. MATERIALS AND METHODS: Fifty-five patients were prospectively enrolled in the study: 33 patients who underwent UAE, seven who underwent myomectomy, and 15 who underwent hysterectomy. Patients had serum FSH and estradiol levels measured on the third day of the menstrual cycle before their procedure and at regular follow-up visits for as long as 6 months. At these intervals, patients were also surveyed regarding menopausal symptoms. RESULTS: Although a mild transient increase in mean FSH level after UAE was noted at 3 months, there were no statistically significant differences among the three groups in mean FSH levels at 1 month, 3 months, or 6 months of follow-up. Menopausal symptoms arose in the UAE and hysterectomy groups, but there was no statistically significant difference or permanent effect in either group. CONCLUSION: There is no significant difference in impact on ovarian function after UAE, hysterectomy, or myomectomy at follow-up for a maximum of 6 months.

Oestradiol induced inhibition of neuroendocrine marker expression in Leydig cells of adult rats.

The objectives of this work were to determine the changes in the expression of neuroendocrine markers in Leydig cell by oestradiol treatment, and to determine whether testosterone is able to recover partially the effects of hormonal suppression induced by oestradiol. Adult male rats were injected daily with either 50 microg of oestradiol or oestradiol plus testosterone propionate (25 mg every 3 days) for 15 days. The animals were sacrificed and testicles were dissected and processed by routine histological protocols. FSH and LH serum levels were determined by radioimmunoassay. The visualization of antigens was achieved by the streptavidin-peroxidase immunohistochemical method. Antibodies against chromogranin A (CrA), S-100 protein (S-100), P substance (PS), synaptofisin (SYN), neurofilament protein (NF), gliofibrillary acidic protein (GFAP) and neuron specific enolase (NSE) were used. The mean LH and FSH serum concentrations were consistently suppressed with hormonal treatments. Intermediate filaments (NF and GFAP) showed no difference in their expression. The expression of S-100, NSE and SYN was significantly lower in both hormone-treated groups. In oestradiol-treated rats, the immunoreactivity of CrA and SP decreased significantly but was restored after testosterone supplementation. Although the nature and functions of many of these substances in Leydig cells remain unknown, these results are consistent with the hypothesis that the expression of some neuroendocrine markers is hormonally controlled.

Toxocara canis infections in a pig model: immunological, haematological and blood biochemistry responses.

The immunological, haematological and enzymatic responses to the inoculation in pigs of 100,000 embryonated eggs of Toxocara canis were studied. Fifteen females were inoculated and three remained as controls. Haematological values were analysed from day 7 p.i. until day 126 p.i. In the inoculated group, white blood cells were raised on day 14 p.i. and eosinophil values on days 7, 14, 21, 35 and 49 p.i. showing significant differences compared with controls (P < 0.05). Absolute eosinophil counts (per ml) presented two rises, the first on days 7, 14 and 21 p.i. and the second on days 35 and 49 p.i. Blood biochemistry was maintained within normal values. Serological examination by ELISA to determine antibody levels against Toxocara canis L2/L3 excretory-secretory (ES) antigens showed values higher than the positive cut-off (1:32) from day 7 p.i. and until the end of the study on day 126 p.i., presenting two peaks: one on day 28 p.i. and the second covering days 49 to 56 p.i. Western blots of sera of inoculated animals presented, from day 7 p.i., two polypeptide bands of 55 and 70 kDa MW and, from day 56 p.i., an additional band of 120 kDa MW, all of which persisted until the end of the study. Immunological responses were sustained over time. No direct correlation was observed between the rise in eosinophils and antibody titres. To validate the conclusions, more studies are required on the polypeptide bands.