Short- and long-term effects of fire and vegetation cover on four lizard species in Amazonian savannas

Ecological succession in tropical savannas is limited by seasonal fire, which affects habitat quality. Although fire may cause negligible or positive effects on animals occupying savannas, most short-term studies (months to a few years) are based on a single temporal sampling snapshot, and long-term studies (decades) are rare. We sampled four lizard species (Rainbow Whiptail, Cnemidophorus lemniscatus (Linnaeus, 1758); Striped Whiptail, Kentropyx striata (Daudin, 1802); Grass Anole, Norops auratus Duméril and Bibron, 1837 = Anolis auratus Daudin, 1802; Amazon Racerunner, Ameiva ameiva (Linnaeus, 1758)) in Amazonian savannas to test the effects of fire and vegetation cover on lizard densities at two temporal scales. In the short term, we use three sampling snapshots to test the effects of fire and vegetation cover on estimated lizard densities over the subsequent 1–5 years. In the long term, we test the effects of fire and changes in vegetation cover over 21 years on current lizard density differences. In the short term, species responses were usually consistent with foraging and thermoregulation modes. However, the results were not consistent among species and years, although the variances in species density explained by year as a random factor were generally low. In the long term, the main effects of fire and vegetation cover show that lizard densities may change spatially, but not necessarily temporarily. Wildfire is a natural resource of savannas and apparently have little impact on resident lizards of that ecosystem.

Focused time-lapse analysis reveals novel aspects of human fertilization and suggests new parameters of embryo viability

STUDY QUESTION

Can focused application of time-lapse microscopy (TLM) lead to a more detailed map of the morphokinetics of human fertilization, revealing novel or neglected aspects of this process?

SUMMARY ANSWER

Intensive harnessing of TLM reveals novel or previously poorly characterised phenomena of fertilization, such as a cytoplasmic wave (CW) preceding pronuclear formation and kinetics of pronuclear chromatin polarization, thereby suggesting novel non-invasive biomarkers of embryo quality.

WHAT IS KNOWN ALREADY

In recent years, human preimplantation development has been the object of TLM studies with the intent to develop morphokinetic algorithms able to predict blastocyst formation and implantation. Regardless, our appreciation of the morphokinetics of fertilization remains rather scarce, currently including only times of polar body II (PBII) emission, pronuclear appearance and fading, and first cleavage. This is not consistent with the complexity and importance of this process, calling for further TLM studies aimed at describing previously unrecognized or undetected morphokinetic events and identifying novel developmental biomarkers.

STUDY DESIGN, SIZE, DURATION

The study involved a retrospective observation by TLM of the fertilization process in 500 oocytes utilized in consecutive ICSI cycles carried out in 2016. A maximum of five fertilized oocytes per patients were included in the analysis to reduce possible patient-specific biases. Oocytes of patients with different diagnoses of infertility where included in the analysis, while cases involving cryopreserved gametes or surgically retrieved sperm were excluded.

PARTICIPANTS/MATERIALS, SETTINGS, METHODS

Microinjected oocytes where assessed by a combined TLM-culture system (Embryoscope). Oocytes that were not amenable to TLM assessment, due to excess of residual corona cells or inadequate orientation for the observation of PBII emission, were not analysed. We identified and monitored 28 parameters relevant to meiotic resumption, pronuclear dynamics, chromatin organization, and cytoplasmic/cortical modifications. Times (T) were expressed as mean ± SD hours post-insemination (p.i.) and analysed, where appropriate, by Paired T Student or Fisher's exact tests.

MAIN RESULTS AND ROLE OF CHANCE

PBII emission was occasionally followed (4.3% of cases) by the transient appearance of a protrusion of the cell surface, the fertilization cone (FC), probably resulting from interaction of the male chromatin with the oocyte cortex. Pronuclear formation was always preceded by a radial CW originating from the initial position of the male pronucleus (PN) and extending towards the oocyte periphery. The appearance of the CW followed a precise sequence, occurring always 2-3 h after PBII emission and shortly before PN appearance. Male and female PN appeared virtually simultaneously at approximately 6.2 h p.i. However, while the female PN always formed cortically and near the site of emission of the PBII, the initial position of the male PN was cortical, intermediate, or central (15.2%, 31.2% and 53.6%, respectively). PN juxtaposition involved rapid and straight movement of the female PN towards the male PN. In addition, the initial position of male PN formation was predictive of the position of PN juxtaposition. It was also observed that nucleolar precursor bodies (NPBs) aligned along the juxtaposition area and this happened considerably earlier for the female PN (8.2 ± 2.6 vs.11.2 ± 4.1 h, P = 0.0001). Although it occurred rarely, displacement of juxtaposed PN to the cortex was strongly associated (P < 0.0001) with direct cleavage into three blastomeres at the first cell division. The times of PN breakdown and first cleavage showed a very consistent trend, occurring earlier or progressively later depending on whether initial male PN positioning was central, intermediate or cortical, respectively. Finally, time intervals between discrete fertilization events were strongly associated with embryo quality on Day 3. For example, longer intervals between disappearance of the cytoplasmic halo and PN breakdown were highly predictive of reduced blastomere number and increased fragmentation (P = 0.0001).

LARGE SCALE DATA

N/A.

LIMITATIONS, REASON FOR CAUTION

Some of the morphokinetic parameters assessed in this study may require better definition to reduce inter-operator annotation variability.

WIDER IMPLICATIONS OF THE FINDINGS

To our knowledge, overall, these data represent the most detailed morphokinetic description of human fertilization. Many of the illustrated parameters are novel and may be amenable to further elaboration into algorithms able to predict embryo quality, as suggested by the findings presented in this study.

STUDY FUNDING/COMPETING INTERESTS

None.

Characterization of the miRNA regulators of the human ovulatory cascade

Ovarian follicular development and ovulation are complex and tightly regulated processes that involve regulation by microRNAs (miRNAs). We previously identified differentially expressed mRNAs between human cumulus granulosa cells (CGCs) from immature early antral follicles (germinal vesicle - GV) and mature preovulatory follicles (metaphase II - M2). In this study, we performed an integrated analysis of the transcriptome and miRNome in CGCs obtained from the GV cumulus-oocyte complex (COC) obtained from IVM and M2 COC obtained from IVF. A total of 43 differentially expressed miRNAs were identified. Using Ingenuity IPA analysis, we identified 7288 potential miRNA-regulated target genes. Two hundred thirty-four of these target genes were also found in our previously generated ovulatory gene library while exhibiting anti-correlated expression to the identified miRNAs. IPA pathway analysis suggested that miR-21 and FOXM1 cooperatively inhibit CDC25A, TOP2A and PRC1. We identified a mechanism for the temporary inhibition of VEGF during ovulation by TGFB1, miR-16-5p and miR-34a-5p. The linkage bioinformatics analysis between the libraries of the coding genes from our preliminary study with the newly generated library of regulatory miRNAs provides us a comprehensive, integrated overview of the miRNA-mRNA co-regulatory networks that may play a key role in controlling post-transcriptomic regulation of the ovulatory process.

Fertility preservation issues in pediatric hematopoietic stem cell transplantation: practical approaches from the consensus of the Pediatric Diseases Working Party of the EBMT and the International BFM Study Group

Fertility preservation is an urgent challenge in the transplant setting. A panel of transplanters and fertility specialists within the Pediatric Diseases Working Party of the European Society for Blood and Marrow Transplantation (EBMT) and the International BFM Study Group provides specific guidelines. Patients and families should be informed of possible gender- and age-specific cryopreservation strategies that should be tailored according to the underlying disease, clinical condition and previous exposure to chemotherapy. Semen collection should be routinely offered to all postpubertal boys at the diagnosis of any disease requiring therapy that could potentially impair fertility. Testicular tissue collection might be offered to postpubertal boys; nevertheless, its use has been unsuccessful to date. Oocyte collection after hormonal hyperstimulation should be offered to postpubertal girls facing gonadotoxic therapies that could be delayed for the 2 weeks required for the procedure. Ovarian tissue collection could be offered to pre-/post-pubertal girls. Pregnancies have been reported after postpubertal ovarian tissue reimplantation; however, to date, no pregnancy has been reported after the reimplantation of prepubertal ovarian tissue or in vitro maturation of pre-/post-pubertal ovarian tissue. Possible future advances in reproductive medicine could change this scenario. Health authorities should prioritize fertility preservation projects in pediatric transplantation to improve patient care and quality of life.

Characterization of the human cumulus cell transcriptome during final follicular maturation and ovulation

Cumulus expansion and oocyte maturation are central processes in ovulation. Knowledge gained from rodent and other mammalian models has revealed some of the molecular pathways associated with these processes. However, the equivalent pathways in humans have not been thoroughly studied and remain unidentified. Compact cumulus cells (CCs) from germinal vesicle cumulus oocyte complexes (COCs) were obtained from patients undergoing in vitro maturation (IVM) procedures. Expanded CCs from metaphase 2 COC were obtained from patients undergoing IVF/ICSI. Global transcriptome profiles of the samples were obtained using state-of-the-art RNA sequencing techniques. We identified 1746 differentially expressed (DE) genes between compact and expanded CCs. Most of these genes were involved in cellular growth and proliferation, cellular movement, cell cycle, cell-to-cell signaling and interaction, extracellular matrix and steroidogenesis. Out of the DE genes, we found 89 long noncoding RNAs, of which 12 are encoded within introns of genes known to be involved in granulosa cell processes. This suggests that unique noncoding RNA transcripts may contribute to the regulation of cumulus expansion and oocyte maturation. Using global transcriptome sequencing, we were able to generate a library of genes regulated during cumulus expansion and oocyte maturation processes. Analysis of these genes allowed us to identify important new genes and noncoding RNAs potentially involved in COC maturation and cumulus expansion. These results may increase our understanding of the process of oocyte maturation and could ultimately improve the efficacy of IVM treatment.

Anti-Müllerian hormone remains highly expressed in human cumulus cells during the final stages of folliculogenesis

This study evaluated whether anti-Müllerian hormone (AMH) was differentially expressed in cumulus (CC) and granulosa (GC) cells from large antral and pre-ovulatory follicles collected from individual follicles in women undergoing in-vitro maturation (IVM) or IVF treatment. Expression studies of AMH, AMH receptor 2, FSH receptor, aromatase and androgen receptor were performed in CC in IVM patients where cumulus-oocyte-complex had expanded, CC in IVM patients where cumulus-oocyte-complex remained compacted, GC from immature follicles and CC and GC from IVF patients. Microarray data on corresponding GC and CC from follicles from IVF patients was included. AMH expression was significantly higher in CC than in GC from both mature and immature follicles and in CC from immature follicles than in CC from pre-ovulatory follicles from IVF patients (P < 0.05). AMH expression was significantly higher in CC that remained compacted compared with those that had expanded (P < 0.008). AMH was correlated to the expression of FSH receptor, androgen receptor and AMH receptor 2 but not to aromatase expression. The expression pattern of AMH receptor 2 reflected that of AMH. AMH may exert intrafollicular functions even in human large antral and pre-ovulatory follicles and may be related to follicular health.

IVM – the first choice for IVF in Italy

In March 2004, a new law was introduced in Italy to regulate assisted reproduction; at present it is impossible to use more than a maximum of three oocytes per IVF cycle, nor can embryos or prezygotes (2PN cells) be selected or cryopreserved. The prohibitions introduced by the new law have, on the one hand, reduced the expectations of success of current techniques and, on the other hand, stimulated clinicians and embryologists to work on new therapeutic strategies so as to offer the highest chances of success with the lowest risks. In-vitro maturation (IVM) of oocytes fits very well with these new requirements: ovarian stimulation is avoided and the handling of spare oocytes is facilitated. The IVM protocol is an intriguing alternative to conventional IVF techniques, since it removes the side-effects of drug stimulation, especially ovarian hyperstimulation syndrome, and it also reduces the costs of the entire procedure, both in terms of 'time consumption' and 'patient/society costs for drugs'. In the authors' IVF centre the IVM technique has been used for more than a year, with significant success in terms of maturation and fertilization rates, percentage of embryo transfers, number of pregnancies and, finally, healthy babies born.

Laparoscopic excision of ovarian dermoid cysts with controlled intraoperative spillage. Safety and effectiveness

OBJECTIVE

To compare the operative and postoperative course in patients undergoing laparoscopy for dermoid cyst to that observed in subjects with other types of ovarian masses and of patients undergoing laparotomy for teratomas.

STUDY DESIGN

Retrospective analysis. From 1994 to 1996, 49 women underwent laparoscopic cystectomy for dermoid cysts. The operative and postoperative course was compared to that of 190 patients undergoing operative laparoscopy for other adnexal masses and to that of 43 patients undergoing laparotomy for dermoid cysts from 1992 to 1996. The cysts were aspirated to reduce spillage and removed via a laparoscopic bag inserted in a 10-mm trocar. Culdotomy was never used. The abdominal cavity was abundantly flushed during the procedure and before closure.

RESULTS

Dermoid cystectomy was successfully performed laparoscopically in 47 of 49 cases. Spillage occurred in 43 cases (88%), and postoperative fever occurred in 3 (6.1%). No case of peritonitis was recorded. Significant differences between laparoscopy and laparotomy were observed in the rate of bilaterality (4% vs. 25%), spillage (88% vs. 9%) and mean hospital stay (37 vs. 83 hours). When laparoscopic excision of dermoid cysts and other masses was compared, we did not observe any significant difference in operative time or complication rates, apart from transient fever.

CONCLUSION

Laparoscopy is safe and effective for dermoid cysts and allows shorter hospitalization than laparotomy. As observed for other benign cysts, laparoscopy should become the technique of choice for the removal of most, if not all, ovarian dermoid cysts.

A gonadotrophin-releasing hormone agonist compared with expectant management after conservative surgery for symptomatic endometriosis

OBJECTIVE

To ascertain whether the frequency of pelvic pain recurrence is reduced and time to symptoms recurrence is prolonged in women with symptomatic endometriosis undergoing conservative surgery and post-operative hormonal therapy compared with women treated with surgery only. Pregnancy rates and time to conception in women wanting children were also evaluated.

DESIGN

A multicentre, prospective, randomised controlled study.

SETTING

Nineteen Italian academic departments and teaching hospitals specialising in reparative and reconstructive surgery.

POPULATION

A total of 269 women undergoing conservative surgery for mild to severe symptomatic endometriosis.

METHODS

After surgery the women were assigned to treatment with subcutaneous goserelin depot injections for six months or to expectant management. Dysmenorrhoea, deep dyspareunia, nonmenstrual pain and general discomfort were graded according to a verbal rating scale from 0 (absent) to 3 (severe) and the scores summed to give a total symptoms score. Only patients with at least one preoperative moderate or severe symptom were enrolled. The women were evaluated regularly for two years.

MAIN OUTCOME MEASURES

Post-operative pain recurrences (total symptoms scores > or = 5), time to recurrence, pregnancy rates and time to conception in the two study groups.

RESULTS

At one- and two-year follow up visits, 14/107 (13.1%) and 19/81 (23.5%) patients had moderate or severe symptoms recurrence in the goserelin group compared with, respectively, 22/103 (21.4%) and 27/74 (36.5%) in the expectant management group (P = 0.143 at 1 year and 0.082 at 2 years). Time to symptoms recurrence was significantly longer in the goserelin group according to survival analysis (Wilcoxon test, P = 0.041). Among women wanting children, few conceptions occurred in both the goserelin (8/69, 11.6%) and the expectant management group (14/76, 18.4%). There was no significant difference at survival analysis (Wilcoxon test, P = 0.427).

CONCLUSION

Post-operative treatment with goserelin significantly prolonged the pain-free interval after conservative surgery for symptomatic endometriosis and did not influence reproductive prognosis.

Zoladex (goserelin acetate) and the anemic patient: results of a multicenter fibroid study

OBJECTIVE

To compare the effects of goserelin acetate treatment with or without iron with iron alone.

DESIGN

Multinational, multicenter, prospective, randomized, double-blind study.

PATIENTS

Premenopausal women with menorrhagia or metrorrhagia and anemia associated with uterine leiomyomata awaiting hysterectomy.

INTERVENTION

Patients were randomized to one of three 12-week treatment groups namely goserelin acetate 3.6 mg once monthly plus placebo iron; 3.6 mg goserelin acetate once monthly plus 600 mg/d iron; or sham injection once monthly plus 600 mg/d iron.

MAIN OUTCOME MEASURE

Preoperative hemoglobin concentration; preoperative uterine and fibroid volumes and operative blood loss.

RESULTS

Considering the entry and preoperative hemoglobin concentrations, there was a difference in least square means of just over 1 g/dL between the goserelin acetate plus iron and iron only groups and 2.6 g/dL between the goserelin acetate plus iron and goserelin acetate only group. These differences were both statistically significant. Uterine and fibroid volumes were decreased in the goserelin acetate-treated patients by between 37% and 40% and 44% and 47%, respectively, compared with 7% decreases for both in the iron only group. The differences in absolute changes were statistically significant for both the goserelin acetate-treated groups versus the iron-treated group. The least square geometric mean operative blood loss was greatest in the iron only group.

CONCLUSION

In the patient with uterine leiomyomata and anemia, goserelin acetate in combination with iron therapy has shown significant advantages over the iron alone in restoring hematologic normality, decreasing uterine and fibroid volumes, and reducing operative blood loss.

[Induction of puberty and maintenance of secondary sexual characteristics in males with thalassemia major]

18 males with beta-thalassaemia major were studied; mean age was 17.6 flAF 4.3, 8 of 18 males evaluated were prepubertal (Tanner 1), 5 were early and mid pubertal (Tanner 2-3) and 5 were full pubertal (Tanner 5). All patients (pts) underwent GnRH test and 61% showed positive response. 8 pts. were treated with hCG; 2 were azoospermic, 6 were aspermic. The starting dose was 1000 IU twice weekly; dose adjustments were made basing on testosterone levels and clinical features. Clinical examination, testosterone assays, semen analysis were performed every 3 months during the treatment period. Therapy was started 18-48 months ago and it is still in progress. Within 12 months of treatment 4 pts progressed to Tanner stage 4, 3 pts to Tanner stage 5, 1 showed no response. Semen analysis showed an improvement in 6 pts: after 12 months of therapy 1 pts was aspermic, 5 were azoospermic, 1 was oligozoospermic. Our data showed that hCG administration is effective in inducing and maintaining secondary sexual character.

[Spontaneous pregnancy in "sterile couples"]

The aim of the study is to evaluate the results of tests performed in "infertile" couples that have obtained spontaneous pregnancy. 953 couples were studied from 1986 to 1991; 108 spontaneous pregnancies occurred (11.1%). All patients were evaluated according to standard procedures recommended by literature. "Female factor" as cause of infertility was present in 41.5%; "cervical factor" was present in 19.4%; "male factor" was present in 48.1% while in 14.8% of the couples evaluated no pathology was showed. In this series, spontaneous pregnancy occurred within 4 year of infertility in more than 90%; no significant difference was present between primary and secondary infertility. A considerable incidence of pathologies was observed in couples that obtained spontaneous pregnancy. Our data suggest that common investigation for infertility may have not a real prognostic value.

Metergoline in the management of normoprolactinemic secondary amenorrhea. A multicentric controlled trial

In a multicentric study, the effect of the antiserotoninergic agent metergoline was evaluated in the management of patients with idiopathic normoprolactinemic secondary amenorrhea (NSA). The awareness that psychological factors might lead to a spontaneous reappearance of menses was also taken into account, and all the patients, after physical, gynecological and laboratory examinations, and the performance of the progesterone withdrawal bleeding test (100 mg i.m.) and the clomiphene citrate test (100 mg p.o./day for 5 days), were treated for 60 days with placebo; only patients showing no menses during placebo administration were later treated with metergoline. 108 patients entered the trial: of these, 48 experienced menses on admission or during placebo administration, and were withdrawn. Of the 60 patients not responding to placebo, 50 were treated for 90 days with metergoline (4 mg t.i.d.), and 23 had menses, ovulatory in 68.4% of cases. A new placebo treatment was accompanied, in the majority of cases, by recurrence of amenorrhea. These results indicate that many patients with NSA may experience a spontaneous disappearance of the disease: in cases more seriously affected metergoline might be a useful therapeutic agent.

Effect of dopamine infusion on serum prolactin concentration in normal and hyperprolactinaemic subjects

The serum prolactin response to intravenous dopamine infusion (5 micrograms . kg-1 . min-1) was measured in twenty-one healthy subjects, in seven hyperprolactinaemic patients without evidence of a pituitary tumour, and in twenty-one patients with prolactinomas. Mean serum prolactin values were significantly suppressed in all three groups, without any significant difference between the degree of suppression. A decrease of serum prolactin to below 50% of basal values occurred in fifteen healthy subjects, in four patients without evidence of pituitary tumour, and in fourteen patients with prolactinomas. These findings demonstrate that most human prolactin-secreting pituitary adenomas are normally suppressible by exogenously administered dopamine and that dopamine infusion is not able to distinguish between tumorous and non-tumorous hyperprolactinaemia. Since intravenously infused dopamine is believed to inhibit prolactin secretion by acting at pituitary level, it is suggested that a normal functioning of pituitary dopamine receptors is maintained in most human prolactinomas.