P-446 Influence of strip thickness and FSH supplementation on follicle growth in the in vitro culture of strips of bovine ovarian cortical tissue in gas-permeable dishes

Study question

Do tissue thickness and FSH supplementation affect follicle growth and health in the vitro culture of bovine ovarian cortical strips (BOCS) in gas-permeable dishes?

Summary answer

Culture of 0.5mm thin BOCS with 5ng/ml FSH does improve follicle health and yield to secondary follicles compared with 1mm thick BOCS

What is known already

Oxygen availability inside tissue has been demonstrated to represent a key factor in follicle health and growth during in vitro culture of bovine and human ovarian cortical strips (HOCS). Although, strip thickness can limit nutrients and gases diffusion in and out of the innermost tissue zone, the presence of the outer medulla in thick strips could positively affect follicle growth. The role of FSH on the progression of primordial to secondary follicles in ovarian organ culture is still debated.

Study design, size, duration

Bovine ovaries from animals aged 8-24 months were collected at a slaughterhouse. In each experiment (n = 3), BOCS of varying thickness collected from the same ovary were cultured with or without FSH in gas-permeable dishes for 10 and 15 days.

Participants/materials, setting, methods

Slices either 0.5mm or 1mm thick were cut with a tissue-slicer and were chopped into 1x1mm2 strips. BOCS were cultured for 10 or 15 days at the same tissue/medium volume ratio (groups of either five 1mm strips or ten 0.5mm strips in 5ml medium) with 0, 1, or 5ng/ml FSH. Follicle stages were assessed by histology. Follicle viability was estimated by labeling with live-dead far red and propidium iodide at the confocal laser scanning microscope.

Main results and the role of chance

Overall, 2314 follicles were analyzed (histology, 998; viability, 1316). At day 0 most follicles were primordial (primordial, 89.4%; primary, 8.7%; secondary, 1.9%), and had a high viability (94.69%). The best follicle growth and viability was observed in 0.5mm thin BOCS cultured with 5ng/ml FSH. In particular, when compared to 1mm thick BOCS cultured with 5ng/ml FSH, 0.5mm thin BOCS cultured with 5ng/ml FSH showed a higher and significant proportion of secondary follicles at day 10 (0.5 vs 1mm, % secondary follicles: 26.5 vs 10, P < 0.05) and a significantly higher proportion of viable follicles at day 15 (0.5 vs 1mm, % viable follicles: 89.4 vs 60.7, P < 0.01).

These results demonstrate that smaller BOCS thickness and 5ng/ml FSH supplementation significantly improve the growth and health of secondary follicles.

Limitations, reasons for caution

Although the bovine is considered a reliable model for human folliculogenesis, the study should be validated on human ovarian tissue.

Wider implications of the findings

A limiting step in the production of mature oocytes starting from primordial follicles is the low yield to secondary follicles at the end of organ culture. Given the similarities between bovine and human folliculogenesis, the best culture conditions herein identified could contribute to the refinement of human in vitro folliculogenesis.

Trial registration number

Not applicable

P–172 Data-independent acquisition-proteomics of human embryo-spent medium and identification of potential embryo biomarkers

Study question

Can human embryo-derived protein(s) serve as viability biomarkers to predict pregnancy outcome, post embryo transfer?

Summary answer

The human embryo-spent medium proteome, using data-independent acquisition (DIA) approach, could identify novel biomarkers for use in elective embryo transfer.

What is known already

Morphological assessment is used for elective embryo transfer. To improve IVF outcomes and to avoid multiple gestations, embryo-viability assessment is required toward single embryo transfer. Embryo proteomics could provide a non-invasive approach to assess embryo viability. With the advent of DIA mode proteomics, a robust proteome of E-SM could be determined.

Study design, size, duration

This was a retrospective study performed between May and December, 2020 using ten E-SMs obtained from ten individual transferable-quality embryos. Frozen E-SMs, following post-thaw, were subjected to LC-MS-MS analysis. Identified proteome profiles were being potentially correlated to embryo quality scores and pregnancy outcomes in terms of live births.

Participants/materials, setting, methods

The E-SMs were processed for proteomic analysis and subjected to reduction, alkylation and trypsin digestion. Trypsin digested samples were desalted followed by LC-MS/MS using DIA method. Obtained results were searched against human peptide spectral library using Skyline. Differentially expressed proteins were identified by MSStat. Individual peptide peak area under the curve was normalized and analyzed using Student t-test. Fold change was calculated to identify differentially regulated proteins in blank and E-SM samples.

Main results and the role of chance

Using a high-resolution mass spectrometer and high throughput DIA method, we identified 5,502 peptides corresponding to 3,396 proteins from blank and E-SM samples, derived from five non-transferred embryos. We observed that 516 proteins were specific to E-SMs vies-a-vies those of embryo-free blank medium. Statistical analysis showed that 25 proteins were significantly present E-SMs vs. blank. Interestingly, we observed that 16 proteins were down regulated and 9 were up regulated in E-SMs vs. blank medium. Furthermore, E-SMs, from transferred embryos, contained 2,467 peptides corresponding to 1,741 proteins; of these, 1, 689 proteins were specific to E-SMs with 60 (58 down regulated and 2 up regulated) of them being significantly expressed in E-SMs vis-à-vis embryo-free blank medium. Considering the available met analysis published data, our study is the first to use DIA acquisition for high-throughput analysis of human embryo proteome and identification of biomarkers of embryo viability and for possible prediction of pregnancy outcome.

Limitations, reasons for caution

Proteins, other than HAS, detected in the blank medium could be because of non-purified HAS or undeclared proteins and DIA approach used. A large cohort study and meta-analysis using DIA mode are required to establish the embryo-proteome having predictive potential for embryo biological viability.

Wider implications of the findings: For the first time, using DIA mode, a global embryo proteome assessment could be made, establishing a novel embryo viability biomarkers. This, along with the morphological analysis, could be practiced for selection of transferable quality embryo(s)

Trial registration number

Not applicable

Association of UGT1A6 gene polymorphism with clinical outcome in pediatric epileptic patients on sodium valproate monotherapy

Pediatric epilepsy comprises chronic neurological disorders characterized by recurrent seizures. Sodium valproate is one of the common antiseizure medications used for treatment. Glucuronide conjugation is the major metabolic pathway of sodium valproate, carried out by the enzyme uridine 5'-diphosphate (UDP) glucuronosyl transferase (UGT) whose gene polymorphisms may alter the clinical outcome. The objective of this study was to assess the association between UGT1A6 genetic polymorphism and clinical outcome in terms of efficacy and tolerability in pediatric epileptic patients on sodium valproate monotherapy. Pediatric epileptic patients (n=65) aged 2-18 years receiving sodium valproate monotherapy for the past one month were included. Genetic polymorphism patterns of UGT1A6 (T19G, A541G, A552C) were evaluated by PCR-RFLP. Clinical outcome was seizure control during the 6 months observation period. Tolerability was measured by estimating the hepatic, renal, and other lab parameters. Out of 65 patients, TT (40%), TG (57%), and GG (3%) patterns were observed in UGT1A6 (T19G) gene, AA (51%), AG (40%), and GG (9%) in (A541G) gene, and AA (43%), AC (43%), and CC (14%) in (A552C) gene. No statistical difference in clinical outcome was found for different UGT1A6 genetic polymorphism patterns. We concluded that different patterns of UGT1A6 genetic polymorphism were not associated with the clinical outcome of sodium valproate in terms of efficacy and tolerability. Sodium valproate was well-tolerated among pediatric patients with epilepsy and can be used as an effective antiseizure medication.

Competing ferri- and antiferromagnetic phases in geometrically frustrated LuFe2O4

We present a detailed study of magnetism in LuFe(2)O(4), combining magnetization measurements with neutron and soft x-ray diffraction. The magnetic phase diagram in the vicinity of T(N) involves a metamagnetic transition separating an antiferro- and a ferrimagnetic phase. For both phases the spin structure is refined by neutron diffraction. Observed diffuse magnetic scattering far above T(N) is explained in terms of near degeneracy of the magnetic phases.

Estimation of larval production in Sanjay Lake and its surrounding ponds in Delhi, India using remote sensing technology

A feasibility study to use remote sensing techniques for estimation of mosquito production in Sanjay lake in east Delhi was carried out. Besides the Sanjay lake, larval production for 12 surrounding remote sensing identifiable ponds was also estimated. Inspite of some limitations the technique is very useful for rapid mapping of major breeding sites, recording temporal changes and estimation of larval production in a cost effective manner in terms of survey cost and time.

Study on the feasibility of delineating mosquitogenic conditions in and around Delhi using Indian Remote Sensing Satellite data

A feasibility study to identify mosquitogenic conditions in six study sites in and around Delhi (Bhalaswa lake, Nazafgarh drain, Seelampur lake, Sanjay lake, Okhla barrage and Hindon barrage) using Indian Remote Sensing Satellites was carried out. The water bodies with marshy areas, vegetation and human settlements were considered as environmental variables responsible for mosquitogenic conditions. Multidate IRS 1A and B, LISS-II satellite data were collected and analysed on Vax 11/780 computers. False colour composite (FCC) images were generated and land cover assessed using supervised classification based on ground truth training sets. Ground truth validation of satellite data was done on satellite pass dates. Concurrent monitoring of larval and adult mosquito density was performed by selecting sub-sites in each study site. The results indicate that mosquitogenic conditions can be identified (with limitation of resolution, i.e. 36.5 m) using FCC images and these images can be used as base maps of study sites. Characterization of study sites based on land cover was done from the view point of mosquitogenic conditions. Spatial changes in mosquito density vis-a-vis changes in environmental variables revealed positive correlation with water bodies and vegetation in some study sites.