Size-fecundity relationships and reproductive investment in female frogs in the Pantanal, south-western Brazil

The ovarian complement of anurans exhibiting different reproductive modes is highly diverse, and intraspecific variation in reproductive output of anurans is generally related to variation in female properties and/or environmental conditions. The size-fecundity relationships, reproductive investment, and correlation between ovary mass and fat body mass were investigated for females of an anuran assemblage in the Pantanal, Brazil. Female body size was positively correlated with clutch size among seven of the eight species analyzed. However, these results seem to be influenced by seasonal variation in fecundity. Interspecific size-fecundity relationships revealed that female SVL was positively correlated with clutch size and egg size regardless of reproductive mode. Among 11 species analyzed, the reproductive investment (RI: ovary mass relative to body mass) varied from 5.5 to 18%, and there were no differences among reproductive modes and activity patterns (explosive/prolonged). RI correlated negatively with female size. Among three Leptodactylus species examined, negative correlation between ovary mass and fat body mass was verified for two species. Variations in the reproductive strategies are closely related to the reproductive activity patterns and reproductive modes exhibited by individual species, but are also influenced by environmental conditions. However, regardless of reproductive mode or activity pattern, each species seems to exhibit a reproductive strategy that allows them to respond differently to the same environmental restrictions.

Benzopyrans from Curvularia sp., an endophytic fungus associated with Ocotea corymbosa (Lauraceae)

An isolate of Curvularia sp. was obtained from the leaves of Ocotea corymbosa, a native plant of the Brazilian Cerrado. The ethyl acetate extract from culture of this fungus afforded two benzopyran derivatives: (2′S)-2-(propan-2′-ol)-5-hydroxy-benzopyran-4-one (2) and 2,3-dihydro-2-methyl-benzopyran-4,5-diol (4); and two known benzopyrans: 2-methyl-5-methoxy-benzopyran-4-one (1) and (2R)-2,3-dihydro-2-methyl-5-methoxy- benzopyran-4-one (3). The structures of 2 and 4 were established on the basis of comprehensive spectroscopic analysis, mainly using 1D and 2D NMR experiments. The benzopyrans 1 and 2 showed weak in vitro antifungal activity against Cladosporium sphaerospermum and C. cladosporioides. Analyses of the biological activities were also carried out on HeLa (human cervix tumor) and CHO (Chinese hamster ovary) cells, aiming to evaluate their potential effects on mammalian cell line proliferation. Results from both cell lines indicated that compound 2 was able to induce cell proliferation: 70% on HeLa cells and 25% on CHO cells. © 2005 Elsevier Ltd. All rights reserved.

Ex vivo biocompatibility tests of regular and white forms of mineral trioxide aggregate

Aim: To examine the genotoxicity and cytotoxicity of regular and white mineral trioxide aggregate (MTA) ex vivo by the single-cell gel (comet) assay and trypan blue exclusion test, respectively. Methodology: Aliquots of 1 × 10 4 Chinese hamster ovary cells were incubated at 37°C for 3 h with grey and white forms of MTA at final concentrations ranging from 1 to 1000 μg mL -1. The negative control group was treated with vehicle control phosphate buffer solution for 3 h at 37°C and the positive control group was treated with methyl metasulfonate (at 1 μg mL -1) for 1 h at 37°C. After incubation, the cells were centrifuged at 180 g for 5 min and washed twice with fresh medium and resuspended with fresh medium. Each individual treatment was repeated three times consecutively to ensure reproducibility. Parameters from single-cell gel (comet) and cytotoxicity assays were assessed by the Kruskal-Wallis nonparametric test. Results: Neither compounds produced genotoxic effects with respect to the single-cell gel (comet) assay in all concentrations evaluated. In the same way, the dose-response relationships of all compounds tested at concentrations ranging from 1 to 1000 μg mL -1 on cell viability assessed by the trypan blue assay displayed no statistically significant differences (P > 0.05) for either endodontic material. Conclusions: Regular (grey) and white MTA are not genotoxins and do not induce cellular death. © 2006 International Endodontic Journal.

Fine needle aspiration biopsy of gastrointestinal stromal tumor presenting as an umbilical mass (Sister Mary Joseph's nodule)

The Sister Mary Joseph (SMJ) nodule is a clinical sign of metastatic cancer involving the umbilicus. The vast majority of these instances represent adenocarcinomas arising from ovarian or colorectal primaries. We present a patient who presented with ascites and the SMJ lesion that turned out to be a metastatic gastrointestinal stromal tumor after fine needle aspiration biopsy was performed. The lesion was subsequently histologically confirmed. Gastrointestinal stroma tumor involving the umbilicus is exceedingly uncommon and only rarely presents in this fashion. The cytomorphological features, differential diagnosis, and comparison with the tissue specimen are made. © 2006 Elsevier Inc. All rights reserved.

Study of DNA damage induced by dental bleaching agents in vitro

Dental bleaching is a simple and conservative procedure for aesthetic restoration of vital and non-vital discolored teeth. Nevertheless, a number of studies have demonstrated the risk of tissue damage from the contact of these agents with the oral mucosa. In the current study, the genotoxic potential associated with exposure to dental bleaching agents was assessed by the single cell gel (comet) assay in vitro. Chinese hamster ovary (CHO) cells in vitro were exposed to six commercial dental bleaching agents (Clarigel Gold - Dentsply; Whitespeed - Discus Dental; Nite White - Discus Dental; Magic Bleaching - Vigodent; Whiteness HP - FGM and Lase Peroxide - DMC). The results pointed out that all dental bleaching agents tested contributed to DNA damage as depicted by the mean tail moment, being the strongest effect observed with the highest dose of hydrogen peroxide (Whiteness HP and Lase peroxide, at a 35% concentration). On the other hand, Magic Bleaching (Vigodent) induced the lowest level of DNA breakage. Negative and positive controls displayed absence and presence of DNA-damaging, respectively. Taken together, these results suggest that dental bleaching agents may be a factor that increases the level of DNA damage. A higher concentration of hydrogen peroxide produced higher noxious activities in the genome as detected by single cell gel (comet) assay.

Nutritional and social hierarchy establishment of the primitively eusocial wasp Mischocyttarus cassununga (Hymenoptera, Vespidae, Mischocyttarini) and related aspects

The results on the nutritional influence in the social hierarchy establishment among females from six colonies of Mischocyttarus cassununga show that: - there was no caste determination in the pre-imaginal period concerning ingested food quantities, however, in relation to qualification (proteins and carbohydrate) the Mann-Whitney test applied showed variation among colonies: in two colonics (colony 3, p=0.0209; colony 4, p=0.0090) the larvae which ingested a higher quantity of solid food became adults of hierarchically higher position, however in two other colonies, colony 1 (p=0.6744) and colony 2 (p=0.3367) this difference was not statistically significant; in two experimentally manipulated colonies the caste determination was observed in the imaginal phase (it was verified that the larger the food quantity consumed, the higher the assumed hierarchical position by the individuals); - adult individuals of hierarchically higher position in two colonies ingested a greater amount of solid than liquid food (Mann-Whitney; p ≤ 0.05), however in the other three colonies there was no difference. It can be seen that for all colonies (2, 3, 4, 5 and 6) the high tendency to solid food ingestion occurs. In colony 1, this data was not collected because the observation purpose was different); - inside the colony hierarchy, the older individuals were the ones that occupied higher hierarchical positions; - more than one inseminated female per colony was found in the two experimentally manipulated colonies ; - ovarian development is greater in inseminated females; - the average height of the 3rd tergite was greater for inseminated females, indicating an adaptation to accommodate larger ovary development (t-Student test; p ≤ 0.05).

Antimicrobial endodontic compounds do not modulate alkylation-induced genotoxicity and oxidative stress in vitro

Objective: To investigate if formocresol, paramonochlorophenol, or calcium hydroxide modulate the genotoxic effects induced by the oxidatively damaging agent hydrogen peroxide (H 2O 2) or the alkylating agent methyl methanesulfonate (MMS) in vitro by using single cell gel (comet) assay. Study design: Chinese hamster ovary (CHO) cells in culture were exposed directly to formocresol, paramonochlorophenol, or calcium hydroxide (adjusted to 100 μg/mL) for 1 hour at 37°C. Subsequently the cultures were incubated with increasing concentrations (0-10 μmol/L) of MMS in phosphate-buffered solution (PBS) for 15 minutes at 37°C or of H 2O 2 at increasing concentrations (0-100 μmol/L) in distilled water for 5 minutes on ice. The negative control cells were treated with PBS for 1 hour at 37°C. The parameter from the comet assay (tail moment) was assessed by the Kruskal-Wallis nonparametric test followed by a post hoc analysis (Dunn test). Results: Clear concentration-related effects were observed for the genotoxin-exposed CHO cells. Increase of MMS-induced DNA damage was not significantly altered by the presence of the compounds tested. Similarly, no significant changes were observed when hydrogen peroxide was used with the endodontic compounds evaluated. Conclusion: Formocresol, paramonochlorophenol, and calcium hydroxide are not able to modulate alkylation-induced genotoxicity or oxidative DNA damage as depicted by the single cell gel (comet) assay. © 2006 Mosby, Inc. All rights reserved.

In vitro metabolism effect on genotoxicity and antigenotoxicity of Agaricus blazei organics and aqueous extracts by the comet assay

There is high interest in the natural products properties due to their use in popular medicine. Agaricus blazei Murrill ss. Heinem. (Ab) is native to Brazil and has been widely disseminated because its medicinal properties. In the present study, the genotoxic and antigenotoxic potential of Ab extracts were investigated using the comet assay. The cells utilized were the non drug-metabolizing line CHO-k1 (Chinese hamster ovary) and the drug-metabolizing line HTC (rat hepatoma). Cells were treated for 3 h in the absence of fetal bovain serum (FBS) with methanolic, hexanic and n-butanolic extracts at 50 μg/ml and 0.75% aqueous extract to test for genotoxicity. Antigenotoxic effects of extracts were determined in cells exposed to the DNA damage inducing agent ethyl methanesulfonate under simultaneous or simultaneous with 1 h pre-incubation conditions. The extracts did not show genotoxicity in HTC, while they were genotoxic in CHO-k1. No antigenotoxic effect was observed with any extract under any condition. These results demonstrate that the metabolism in presence or in absence has a direct influence on the genotoxicity of these extracts. © 2006 The Japan Mendel Society.

Uma revisão sistemática sobre o uso de agonistas e antagonistas do GnRH em pacientes más respondedoras à estimulação ovariana

The purpose of this investigation was to make a systematic review of the medical literature in order to compare the efficacy of GnRH antagonists and agonists for poor responders to ovarian stimulation. According to the data collected, the use of GnRH antagonist protocols showed better results in comparison to long protocols with a GnRH agonist regarding the following aspects: lower cycle cancellation rate due to poor ovarian response; higher number of oocytes retrieved; higher clinical pregnancy rate per initiated cycle. Nevertheless, these results were not observed when the flare-up protocols of GnRH agonists were used. Moreover the number of oocytes retrieved with GnRH agonist was significantly higher in relation to the GnRH antagonist.

Uso da suplementação de LH recombinante na estimulação ovariana com protocolos de FSH recombinante e agonistas do GnRH: Uma revisão da literatura

The purpose of this review was to assess the efficacy of recombinant LH (r-LH) supplementation for controlled ovarian stimulation in recombinant FSH (r-FSH) and GnRH-agonist (GnRH-a) protocol for IVF/ICSI cycles. Search strategies included on-line surveys of databases from 1990 to 2006. Four trials fulfilled the inclusion criteria (Lisi et al. 2002, Humaidan et al. 2004, Marrs et al. 2004, Tarlatzis et al. 2006). When the review was carried out advantages were observed for the r-LH supplementation protocol with respect to a fewer days of stimulation, a fewer total amount of r-FSH administered and a higher serum estradiol levels on the day of hCG administration. However, these differences were not observed in number of oocyte retrieved, number of mature oocytes, clinical pregnancy per oocyte retrieval, implantation and miscarriage rates. Nevertheless, more randomized controlled trials are necessary before evidence-based recommendations regarding exogenous r-LH supplementation in ovarian stimulation protocols with r-FSH and GnRH-a for assisted reproduction treatment can be provided.

O emprego de hormônio luteinizante recombinante associado ao hormônio folículo-estimulante recombinante nos protocolos de estimulação ovariana com antagonista do GnRH

The purpose of this investigation was to verify the efficacy of recombinant LH supplementation for controlled ovarian stimulation in GnRH-antagonist protocol for assisted reproductive technologies cycles. Search strategies included on-line surveys of databases from 1990 to 2006. In this review and meta-analysis, the observed advantages for the LH supplementation protocol were a higher serum estradiol levels on the day of hCG administration and a higher number of mature oocytes. However, there were no differences observed in the total amount of r-FSH administered, days of stimulation, number of oocyte retrieved, the clinical pregnancy rate per oocyte retrieval, the implantation rate and miscarriage rate. This result demonstrates that the association of r-LH with r-FSH may prevent any decrease in estradiol after antagonist administration and a significant higher number of mature oocytes was obtained. Nevertheless, additional randomized controlled trials are needed confirm these observations.

GnRH agonist versus GnRH antagonist in poor ovarian responders: A meta-analysis

The aim of this meta-analysis was to compare the efficacy of gonadotrophin antagonist (GnRH-ant) versus GnRH agonist (GnRHa) as coadjuvant therapy for ovarian stimulation in poor ovarian responders in IVF/intracytoplasmic sperm injection cycles. Search strategies included on-line surveys of databases such as MEDLINE, EMBASE and others. A fixed effects model was used for odds ratio (OR) and effect size (weighted mean difference, WMD). Six trials fulfilled the inclusion criteria (randomized controlled trials). There was no difference between GnRH-ant and GnRHa (long and flare-up protocols) with respect to cycle cancellation rate, number of mature oocytes and clinical pregnancy rate per cycle initiated, per oocyte retrieval and per embryo transfer. When the mete-analysis was applied to the two trials that had used GnRH-ant versus long protocols of GnRHa, a significantly higher number of retrieved oocytes was observed in the GnRH-ant protocols [P = 0.018; WMD: 1.12 (0.18, 2.05)]. However, when the meta-analysis was applied to the four trials that had used GnRH-ant versus flare-up protocols, a significantly higher number of retrieved oocytes (P = 0.032; WMD: -0.51, 95% CI -0.99, -0.04) was observed in the GnRHa protocols. Nevertheless, additional randomized controlled trials with better planning are needed to confirm these results.

Laser-assisted hatching of cryopreserved-thawed embryos by thinning one quarter of the zona

Laser-assisted hatching is little documented in the literature regarding its efficacy in cryopreserved-thawed (CT) embryo transfer cycles. The aim of the present study was to evaluate in a randomized manner the efficacy of thinning one quarter of the zona pellucida of CT embryos to a depth of 50-80% of the original thickness, via laser treatment (the qLZT-AH procedure), in improving implantation and pregnancy rates. Two populations were studied: population I, patients who had all their supernumerary embryos cryopreserved, regardless of their morphology, and population II, patients at risk of ovarian hyperstimulation syndrome who had all their embryos cryopreserved. Artificial and natural protocols were used for the embryo transfers. A total of 350 laser-thinned CT embryos were compared with 352 intact zona embryos. No difference in implantation or pregnancy rate was found after using qLZT-AH in either population. These findings suggest that qLZT-AH should not be routinely performed in cryopreserved embryo programmes.

Glandular dots of Caesalpinia echinata Lam. (Leguminosae): Distribution, structure and ultrastructure

The structure and ultrastructure of immature to fully mature glandular dots in the leaf, floral organs and fruit, and their secretion components were described in Caesalpinia echinata Lam. (Leguminosae) for the first time. Data showed that glandular dots were groups of idioblasts with contents that reacted positively for both lipophilic and hydrophilic substances. Idioblasts originated from successive divisions of the ground meristem cells or mesophyll cells of an ovary of a fertilized flower. Following division, cells enlarged, the cytoplasm became denser and its content became full. No idioblasts were observed after fruit sclerification. Besides these mixed-content idioblasts, some cells in the sepals, petals and mesocarp were found to contain phenolic compounds, which probably represent a kind of constitutive defense mechanism, once the flowers and fruits become highly fitness-valued parts of the plant and can be commonly attacked. The contents of the idioblasts are released as the growth rate of the embryo increases, indicating that the plant probably diverts the precursors of secondary metabolites into the primary metabolism, at this critical time of embryo development.

Follicular dynamics and plasma FSH and progesterone concentrations during follicular deviation in the first post-ovulatory wave in Nelore (Bos indicus) heifers

The objective of the present study was to characterize ovarian follicular dynamics and hormone concentrations during follicular deviation in the first wave after ovulation in Nelore (Bos indicus) heifers. Ultrasonographic exams were performed and blood samples were collected every 12 h from the day of estrus until 120-144 h after ovulation in seven females. Deviation was defined as the point at which the growth rate of the dominant follicle became greater than the growth rate of the largest subordinate follicle. Deviation occurred approximately 65 h after ovulation. Growth rate of the dominant follicle increased (P < 0.05) after deviation, while growth rate of the subordinate follicle decreased (P < 0.05). Diameter of the dominant follicle did not differ from the subordinate follicle at deviation (approximately 5.4 mm). The dominant follicle (7.6 mm) was larger (P < 0.05) than the subordinate follicle (5.3 mm) 96 h after ovulation or 24 h after deviation. Plasma FSH concentrations did not change significantly during the post-ovulatory period. The first significant increase in mean plasma progesterone concentration occurred on the day of follicular deviation. In conclusion, the interval from ovulation to follicular deviation (2.7 days) was similar to that previously reported in B. taurus females, but follicles were smaller. Diameters of the dominant follicle and subordinate follicle did not differ before deviation and deviation was characterized by an increase in dominant follicle and decrease in subordinate follicle growth rate. Variations in FSH concentrations within 12-h intervals were not involved in follicular deviation in Nelore heifers. © 2006 Elsevier B.V. All rights reserved.