BACKGROUND: Malaria, a global health concern, is caused by parasites of the Plasmodium genus, which undergo gametogenesis in the midgut of mosquitoes after ingestion of an infected blood meal. The resulting male and female gametes fuse to form a zygote, which differentiates into a motile ookinete. After traversing the midgut epithelium, the ookinete differentiates into an oocyst on the basal side of the epithelium.
METHODS: Membrane proteins with increased gene expression levels from the gamete to oocyst stages in P. berghei were investigated utilizing PlasmoDB, the functional genomic database for Plasmodium spp. Based on this analysis, we selected the 184-kDa membrane protein, Pb184, for further study. The expression of Pb184 was further confirmed through immunofluorescence staining, following which we examined whether Pb184 is involved in fertilization using antibodies targeting the C-terminal region of Pb184 and biotin-labeled C-terminal region peptides of Pb184.
RESULTS: Pb184 is expressed on the surface of male and female gametes. The antibody inhibited zygote and ookinete formation in vitro. When mosquitoes were fed on parasite-infected blood containing the antibody, oocyst formation decreased on the second day after feeding. Synthesized biotin-labeled peptides matching the C-terminal region of Pb184 bound to the female gamete and the residual body of male gametes, and inhibited differentiation into ookinetes in the in vitro culture system.
CONCLUSIONS: These results may be useful for the further studying the fertilization mechanism of Plasmodium protozoa. There is also the potential for their application as future tools to prevent malaria transmission.

The complex evolutionary history of wheat has shaped its associated root microbial community. However, consideration of impacts from agricultural intensification have been limited. This study investigated how endogenous (genome polyploidization), and exogenous (introduction of chemical fertilizers) factors have shaped beneficial rhizobacterial selection. We combined culture -independent and -dependent methods to analyze rhizobacterial community composition and its associated functions at the root-soil interface from a range of ancestral and modern wheat genotypes, grown with and without the addition of chemical fertilizer. In controlled pot experiments, fertilization and soil compartment (rhizosphere, rhizoplane) were the dominant factors shaping rhizobacterial community composition, whereas the expansion of the wheat genome from diploid to allopolyploid caused the next greatest variation. Rhizoplane-derived culturable bacterial collections tested for plant growth-promoting (PGP) traits revealed that fertilization reduced the abundance of putative plant growth-promoting rhizobacteria (PGPR) in allopolyploid wheats but not in wild wheat progenitors. Taxonomic classification of these isolates showed that these differences were largely driven by reduced selection of beneficial root bacteria representative of the Bacteroidota phylum in allopolyploid wheats. Furthermore, the complexity of supported beneficial bacterial populations in hexaploid wheats was greatly reduced in comparison to diploid wild wheats. We therefore propose that the selection of root-associated bacterial genera with PGP functions may be impaired by crop domestication in a fertilizer-dependent manner, a potentially crucial finding to direct future plant breeding programs to improve crop production systems in a changing environment.

Sexual selection is known to play a major role in the evolution of insect sperm size, whereas natural selection is thought to be a major driver of insect egg size. Despite these differing forms of selection operating, it is possible coevolution between male and female gametes can occur owing to their vital interactions during fertilization. We tested egg-sperm coevolution in insects and found that longer sperm correlated to longer and wider eggs. Moreover, the size of the entry point of sperm into insect eggs (micropyles), was positively related to the diameter of sperm, on average being approximately three times the diameter of the sperm. This suggests a function in reducing and channelling sperm entry, but potentially still leaving space for movement. Our work suggests that greater attention needs to be paid to egg-sperm interactions prior to the point of fertilization as they may influence the evolution of gametes.

Mitochondria are maternally inherited, but the mechanisms underlying paternal mitochondrial elimination after fertilization are far less clear. Using Drosophila, we show that special egg-derived multivesicular body vesicles promote paternal mitochondrial elimination by activating an LC3-associated phagocytosis-like pathway, a cellular defense pathway commonly employed against invading microbes. Upon fertilization, these egg-derived vesicles form extended vesicular sheaths around the sperm flagellum, promoting degradation of the sperm mitochondrial derivative and plasma membrane. LC3-associated phagocytosis cascade of events, including recruitment of a Rubicon-based class III PI(3)K complex to the flagellum vesicular sheaths, its activation, and consequent recruitment of Atg8/LC3, are all required for paternal mitochondrial elimination. Finally, lysosomes fuse with strings of large vesicles derived from the flagellum vesicular sheaths and contain degrading fragments of the paternal mitochondrial derivative. Given reports showing that in some mammals, the paternal mitochondria are also decorated with Atg8/LC3 and surrounded by multivesicular bodies upon fertilization, our findings suggest that a similar pathway also mediates paternal mitochondrial elimination in other flagellated sperm-producing organisms.

Melatonin is a hormone produced by the pineal gland and it has antioxidant properties.
This study aimed to evaluate the effects of melatonin on assisted reproductive technologies through a systematic review and a meta-analysis.
Search strategies were used in PubMed and in other databases covering the last 15 years. After screening for eligibility, 17 articles were selected for the systematic review. For the meta-analysis statistics, two groups were formed, the treatment group (with melatonin) and the control group (without melatonin) for various assisted reproduction outcomes.
The main results were that no statistical differences were found concerning the clinical pregnancy outcome (p = 0.64), but there was a statistical difference with respect to Mature Oocytes (MII) (p = 0.001), antral follicle count (p = 0.0002), and the fertilization rate (p ≤ 0.0001).
Melatonin had beneficial effects such as the improvement in the fertilization rate, although the authors did not obtain significance in the clinical pregnancy rate.

BACKGROUND: In the realm of in vitro fertilization (IVF), artificial intelligence (AI) models serve as invaluable tools for clinicians, offering predictive insights into ovarian stimulation outcomes. Predicting and understanding a patient\'s response to ovarian stimulation can help in personalizing doses of drugs, preventing adverse outcomes (eg, hyperstimulation), and improving the likelihood of successful fertilization and pregnancy. Given the pivotal role of accurate predictions in IVF procedures, it becomes important to investigate the landscape of AI models that are being used to predict the outcomes of ovarian stimulation.
OBJECTIVE: The objective of this review is to comprehensively examine the literature to explore the characteristics of AI models used for predicting ovarian stimulation outcomes in the context of IVF.
METHODS: A total of 6 electronic databases were searched for peer-reviewed literature published before August 2023, using the concepts of IVF and AI, along with their related terms. Records were independently screened by 2 reviewers against the eligibility criteria. The extracted data were then consolidated and presented through narrative synthesis.
RESULTS: Upon reviewing 1348 articles, 30 met the predetermined inclusion criteria. The literature primarily focused on the number of oocytes retrieved as the main predicted outcome. Microscopy images stood out as the primary ground truth reference. The reviewed studies also highlighted that the most frequently adopted stimulation protocol was the gonadotropin-releasing hormone (GnRH) antagonist. In terms of using trigger medication, human chorionic gonadotropin (hCG) was the most commonly selected option. Among the machine learning techniques, the favored choice was the support vector machine. As for the validation of AI algorithms, the hold-out cross-validation method was the most prevalent. The area under the curve was highlighted as the primary evaluation metric. The literature exhibited a wide variation in the number of features used for AI algorithm development, ranging from 2 to 28,054 features. Data were mostly sourced from patient demographics, followed by laboratory data, specifically hormonal levels. Notably, the vast majority of studies were restricted to a single infertility clinic and exclusively relied on nonpublic data sets.
CONCLUSIONS: These insights highlight an urgent need to diversify data sources and explore varied AI techniques for improved prediction accuracy and generalizability of AI models for the prediction of ovarian stimulation outcomes. Future research should prioritize multiclinic collaborations and consider leveraging public data sets, aiming for more precise AI-driven predictions that ultimately boost patient care and IVF success rates.

Agricultural grasslands play an important role in conserving the biodiversity of the European cultural landscape. Both, litter cover and soil nutrient availability, change with grassland management, but it is not well-studied how seedling recruitment and growth of multiple grassland species are influenced by their single or combined effects. Therefore, we studied the effects of nitrogen fertilization (100 kg N per year and ha) and litter cover (250 gdw per m2) on seedling recruitment and growth of 75 temperate grassland species (16 graminoid species, 51 forb species, 8 legume species) in a full factorial microcosm experiment. Overall, fertilizer reduced seedling emergence, while litter cover increased it even when combined with fertilization. Fertilization increased seedling height and biomass, and the combination of fertilizer and litter resulted in even stronger responses. Litter cover alone did not influence seedling biomass or seedling height. While the overall direction of treatment effects was similar across functional groups, their strengths were mostly weaker in graminoids than in non-legume forbs and legumes. Positive litter effects on seedling emergence were stronger in large-seeded species. Positive fertilization effects on seedling growth were stronger in small-seeded species, while their seedling biomass was negatively affected by litter cover. In summary, our results show for multiple grassland species that the combination of litter cover and fertilization modulates their single effects. The varying sensitivity of how grassland species representing different functional groups and seed sizes respond with their seedling emergence and growth to litter cover and nitrogen fertilization indicates that the consequences of land-use change on grassland diversity and composition already start to manifest in the earliest stages of the plant life cycle.

BACKGROUND: Experiences of delayed conception and infertility have been reported among women. However, the concept of intersectionality is rarely utilised in studies of infertility, and it is particularly uncommon in research from low- and middle- income countries.
OBJECTIVE: What are the lived experiences of women with delayed conception in low to -middle income neighbourhoods of Delhi, India?
METHODS: This was a qualitative study (n = 35) that recruited women who had failed to conceive after 18 months of regular unprotected sexual intercourse. Data were collected between February and July 2021. Data were collected through focus group discussions in low income to middle income neighbourhoods of Delhi, India. Analysis identified themes related to intersecting axes of inequality.
RESULTS: The results showed that gender intersected with economics, masculinity, patriarchal norms and class to influence the experiences of women. The intersection of gender, economics and patriarchal norms compromised women\'s agency to be active generators of family income, and this dynamic was exacerbated by patrilocal residence. In addition, masculinity contributed to stigmatisation and blaming of women, due to the inaccurate perception that men did not contribute to a couple\'s infertility. The intersection of gender and social class in medical settings created barriers to women\'s access to medical information.
CONCLUSIONS: Findings from this study provide representative examples of the variety of axes of inequality that shape women\'s experiences in the study setting. Although these findings may not be generalisable to all women who are experiencing delayed conception, they highlight a need for improved awareness and education on infertility, as well as a need to ensure the availability and accessibility of fertility care for couples in need.

UNASSIGNED: Post-ovulatory aging is a time-dependent deterioration of ovulated oocytes and a major limiting factor reducing the fitness of offspring. This process may lead to the activation of cell death pathways like apoptosis in oocytes.
UNASSIGNED: We evaluated oocyte membrane integrity, egg developmental competency, and mRNA abundance of apoptosis-related genes by RT-qPCR. Oocytes from zebrafish Danio rerio were retained in vivo at 28.5°C for 24 h post-ovulation (HPO). Viability was assessed using trypan blue (TB) staining. The consequences of in vivo oocyte aging on the developmental competence of progeny were determined by the embryo survival at 24 h post fertilization, hatching, and larval malformation rates.
UNASSIGNED: The fertilization, oocyte viability, and hatching rates were 91, 97, and 65% at 0 HPO and dropped to 62, 90, and 22% at 4 HPO, respectively. The fertilizing ability was reduced to 2% at 8 HPO, while 72% of oocytes had still intact plasma membranes. Among the apoptotic genes bcl-2 (b-cell lymphoma 2), bada (bcl2-associated agonist of cell death a), cathepsin D, cathepsin Z, caspase 6a, caspase 7, caspase 8, caspase 9, apaf1, tp53 (tumor protein p53), cdk1 (cyclin-dependent kinase 1) studied, mRNA abundance of anti-apoptotic bcl-2 decreased and pro-apoptotic cathepsin D increased at 24 HPO. Furthermore, tp53 and cdk1 mRNA transcripts decreased at 24 HPO compared to 0 HPO.
UNASSIGNED: Thus, TB staining did not detect the loss of oocyte competency if caused by aging. TB staining, however, could be used as a simple and rapid method to evaluate the quality of zebrafish oocytes before fertilization. Taken together, our results indicate the activation of cell death pathways in the advanced stages of oocyte aging in zebrafish.

We predicted the energy balance of cows from milk traits and estimated the genetic correlations of predicted energy balance (PEB) with fertility traits for the first three lactations. Data included 9,646,606 test-day records of 576,555 Holstein cows in Japan from 2015 to 2019. Genetic parameters were estimated with a multiple-trait model in which the records among lactation stages and parities were treated as separate traits. Fertility traits were conception rate at first insemination (CR), number of inseminations (NI), and days open (DO). Heritability estimates of PEB were 0.28-0.35 (first lactation), 0.15-0.29 (second), and 0.09-0.23 (third). Estimated genetic correlations among lactation stages were 0.85-1.00 (first lactation), 0.73-1.00 (second), and 0.64-1.00 (third). Estimated genetic correlations among parities were 0.82-0.96 (between first and second), 0.97-0.99 (second and third), and 0.69-0.92 (first and third). Estimated genetic correlations of PEB in early lactation with fertility were 0.04 to 0.19 for CR, -0.03 to -0.19 for NI, and -0.01 to -0.24 for DO. Genetic improvement of PEB is possible. Lower PEB in early lactation was associated with worse fertility, suggesting that improving PEB in early lactation may improve reproductive performance.