Period Of Embryonic Development Research Articles

The Effect of Hypokinesia on the Dynamics of the Formed Elements of Blood during the Embryonic Period of Prenatal Development in Pregnant Rabbits

The erythroformula and leucoformula indicators changed in the rabbits that experienced hypokinesia during the embryonic stage of pregnancy. Compared to the rabbits that spent the pregnancy period under normal conditions, changes in concentrations of leukoformula indicators such as leukocytes, lymphocytes, monocytes, and granulocytes were detected in rabbits exposed to hypokinesia. While significant changes in erythroformula indicators: erythrocytes, average corpuscular volume of erythrocytes and hemoglobin capacity, erythrocyte sedimentation rate did not occur. The results of our studies have shown that prenatal hypokinesia causes noticeable changes in the blood coagulation system. On the other hand, changes in the coagulation system under the influence of prenatal hypokinesia were found to occur in the first periods of postnatal ontogenesis, had a continuous nature, and were maintained until the full maturity of postnatal development. Due to the effect of the hypokinesia factor, the changes in the mentioned indicators lead to the emergence of severe pathological diseases in most cases.

First ontogenesis and bioecological study of Sciobia bouvieri (Orthoptera, Gryllidae), a North African endemic species

This study aimed to investigate the bioecology and life cycle of the Algerian endemic Sciobia bouvieri, which remained unknown until recently. A combined approach of field sampling through direct searching and captive rearing of S. bouvieri nymphs under natural conditions was employed to determine the population ontogeny. The life cycle was found to comprise three stages: egg, nymph, and adult. The embryonic development period ranged from 22 to 30 days. Females laid an average of 9.4 ± 1.3 eggs per clutch. The nymphal stage consisted of six instars, lasting an average of 306.5 days. Adult longevity varied, with males living 32.3 ± 16.2 days and females living 23.9 ± 22.4 days. The duration of the ontogenesis cycle of Sciobia bouvieri in nature showed that it has a univoltine life cycle with summer and winter diapauses occurring during the fourth and fifth larval stages, respectively. These diapauses are likely controlled by photoperiod and temperature. This is the first study of the bioecology and life cycle of this North African endemic species.

Features of the state of extraembryonic structures in miscarriage early terms of pregnancy

Background. Despite the modern achievements of medicine, miscarriage remains the main problem of obstetrics and gynecology science and practice. Purpose – to assess the features of the state of extraembryonic structures in case of miscarriage in the early stages of gestation. Materials and Methods. Under observation were 32 patients (main group) with a verified threat of pregnancy termination with bleeding in the embryonic period of gestation (up to 10 weeks) and 20 women (control group) with a physiological course of early pregnancy. The exclusion criteria from the study were patients with induced pregnancy, multiple pregnancies, anomalies of the development of female genital organs. All patients underwent a standard clinical and laboratory examination. During the ultrasound examination, both the state of the embryo and the state of extraembryonic structures were evaluated: the volume of the fertilized egg (V f/e), the average internal diameter of the yolk sac, the nature of vascularization of the corpus luteum, the state of hemodynamics in the myometrium. During transvaginal ultrasound, the chorionic volume (Vc) was calculated and its vascularization index (VI) was evaluated using a special three-dimensional VOCAL program. Results. Analysis of embryo biometrics in the studied groups did not reveal any significant difference. When assessing the state of extra-embryonic structures, we found that the volume of the fertilized egg and the average internal diameter of the yolk sac in women with miscarriage in the embryonic period of gestation was significantly lower. The volume of the corpus luteum of the ovary in the main group was equal to 3.0±0.3 cm3 in the control group – 5.3±0.61 cm3 , (p < 0.05). Vascularization of the corpus luteum in patients with bleeding in early pregnancy was also reduced. In patients with threatened termination of pregnancy with bleeding, Vc was 32.5±2.08 cm3 in control 71.6±2.4 cm3 . The vascularization index of the chorion in pregnant women of the main group was equal to 9.5±1.2, while in women with a physiological course of gestation it was 19.1±1.7 (p<0.05). When evaluating the hemodynamics in the myometrium, it was also established that the resistance index in the uterine and spiral arteries in the patients of the main group was significantly higher compared to the pregnant women of the control group. Conclusions. When there is a threat of pregnancy termination with bleeding in the embryonic period of intrauterine development of the child, significant changes occur in extraembryonic structures. A decrease in the volume of the fertilized egg, the average internal diameter of the yolk sac, blood flow disorders in the corpus luteum and myometrium, a decrease in vascularization of the chorion and its hypoplasia create a high risk of developing placental dysfunction and worsen the prognosis of pregnancy.

In ovo probiotic supplementation supports hatchability and improves hatchling quality in broilers

In modern broilers, the period of embryonic development constitutes a greater proportion of a broiler's productive life. Hence, optimum embryonic development can exert a significant influence not only on chick hatchability and hatchling quality but also on overall broiler growth and performance. Further healthy and active hatchlings are correlated with improved posthatch performance. In this regard, probiotics are good candidates to mediate early-life programming. Therefore, we evaluated the effect of In ovo probiotic spray application on broiler hatchability and hatchling quality. The experiment was set out as a completely randomized study with 2 independent trials. In each trial, 540 eggs (Ross 308) were either sprayed with phosphate buffered saline (PBS; control) or probiotics [∼9 log CFU/egg of Lactobacillus rhamnosus NRRL B-442(LR) or Lactobacillus paracasei DUP 13076 (LP)] during incubation. On day 18, eggs were transferred to the hatcher and set up for hatching. Starting on day 19, eggs were observed for hatching to determine the spread of hatch and hatchability. Hatched chicks were then assessed for quality using the Tona and Pasgar score and morphometric measurements including hatchling weight, yolk-free-body-mass and hatchling length were measured. Further, chicks were reared in floor pens for 3 wk to assess posthatch growth. Overall, In ovo probiotic supplementation improved hatchability and hatchling quality. Specifically, the spray application of LP improved hatchability by ∼ 5% without affecting the spread of hatch. Further, both LR and LP significantly improved Pasgar and Tona score, indicating an improvement in hatchling quality. Also, LP and LR significantly improved hatchling weight, yolk-free-body-mass, and posthatch growth in chicks. LR significantly improved hatchling weight and hatchling length (P < 0.05). Moreover, this increase in posthatch growth was positively correlated with hatchling weight in the probiotic groups. Overall, our study demonstrates that In ovo probiotic application exerts a positive effect on hatchability, hatchling quality, and subsequent posthatch growth.

Studies on the embryonic development and larval infection potential of the stomach bot flies, Gasterophilus pecorum

Endangered Przewalski's horses have faced severe infections from Gasterophilus pecorum (Diptera, Gastrophilidae) in Xinjiang's Kalamaili Nature Reserve (KNR). This study examines G. pecorum's development and infection patterns in embryonic and larval stages, crucial for understanding horse botfly disease in desert grasslands. For the incubation of G. pecorum fertilized eggs, we established the six distinct temperature gradients: 16 °C, 20 °C, 24 °C, 28 °C, 30 °C, and 32 °C. Using the least squares method, we calculated the correlation between the developmental threshold temperature of the eggs and their cumulative effective temperature. Furthermore, we meticulously recorded the survival duration of the larvae across a spectrum of temperature gradients (−20 °C, −10 °C, 4 °C, 10 °C, 20 °C, and 30 °C) and under varying conditions (dark and light). This method allows us to analyze and interpret the impact of these environmental factors on larval survival durations. 1) The formula for predicting the embryonic development period of G. pecorum was N = (182.7 ± 12.03)/[T-(3.191 ± 1.48)], where the developmental threshold temperature was 3.191 ± 1.48 °C, and the effective accumulated temperature was 182.7 ± 12.03 d°C 2) The model describing the relationship between the embryonic development rate and temperature was: y = 0.0001x2+0.0007x+0.0378, demonstrating a positive correlation between the development rate and temperature (R-sq = 0.989, p < 0.001). 3) Larvae in the dark group exhibited a longer survival time, with the longest being 9 months at 4 °C. The adaptation of G. pecorum's embryonic development to cold temperature, combined with the extended survival period of larvae in the egg state, significantly increases the infection potential of G. pecorum in colder climates. This discovery offers essential insights into the predominance of G. pecorum in the KNR region and provides a crucial biological basis for the prevention of myiasis and the conservation of vulnerable species, such as Przewalski's horses.

Real-time study of spatio-temporal dynamics (4D) of physiological activities in alive biological specimens with different FOVs and resolutions simultaneously

This article reports the development of a microscopy imaging system that gives feasibility for studying spatio-temporal dynamics of physiological activities of alive biological specimens (over entire volume not only for a particular section, i.e., in 4D). The imaging technology facilitates to obtain two image frames of a section of the larger specimen (∼mm\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim \ ext {mm}$$\\end{document}) with different FOVs at different resolutions or magnifications simultaneously in real-time (in addition to recovery of 3D (volume) information). Again, this imaging system addresses the longstanding challenges of housing multiple light sources (6 at the maximum till date) in microscopy (in general) and light sheet fluorescence microscopy (LSFM) (in particular), by using a tuneable pulsed laser source (with an operating wavelength in the range ∼420\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim 420$$\\end{document}–670 nm) in contrast to the conventional CW laser source being adopted for inducing photo-excitation of tagged fluorophores. In the present study, we employ four wavelengths (∼\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim$$\\end{document} 488 nm, 585 nm, 590 nm, and 594 nm). Our study also demonstrates quantitative characterization of spatio-temporal dynamics (velocity—both amplitude and direction) of organelles (mitochondria) and their mutual correlationships. Mitochondria close to the nucleus (or in clustered cells) are observed to possess a lower degree of freedom in comparison to that at the cellular periphery (or isolated cells). In addition, the study demonstrates real-time observation and recording of the development and growth of all tracheal branches during the entire period (∼95\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim 95$$\\end{document} min) of embryonic development (Drosophila). The experimental results—with experiments being conducted in various and diversified biological specimens (Drosophila melanogaster, mouse embryo, and HeLa cells)—demonstrate that the study is of great scientific impact both from the aspects of technology and biological sciences.

Metabonomics and Transcriptomics Analyses Reveal the Development Process of the Auditory System in the Embryonic Development Period of the Small Yellow Croaker under Background Noise.

Underwater noise pollution has become a potential threat to aquatic animals in the natural environment. The main causes of such pollution are frequent human activities creating underwater environmental noise, including commercial shipping, offshore energy platforms, scientific exploration activities, etc. However, in aquaculture environments, underwater noise pollution has also become an unavoidable problem due to background noise created by aquaculture equipment. Some research has shown that certain fish show adaptability to noise over a period of time. This could be due to fish's special auditory organ, i.e., their "inner ear"; meanwhile, otoliths and sensory hair cells are the important components of the inner ear and are also essential for the function of the auditory system. Recently, research in respect of underwater noise pollution has mainly focused on adult fish, and there is a lack of the research on the effects of underwater noise pollution on the development process of the auditory system in the embryonic development period. Thus, in this study, we collected embryo-larval samples of the small yellow croaker (Larimichthys polyactis) in four important stages of otic vesicle development through artificial breeding. Then, we used metabonomics and transcriptomics analyses to reveal the development process of the auditory system in the embryonic development period under background noise (indoor and underwater environment sound). Finally, we identified 4026 differentially expressed genes (DEGs) and 672 differential metabolites (DMs), including 37 DEGs associated with the auditory system, and many differences mainly existed in the neurula stage (20 h of post-fertilization/20 HPF). We also inferred the regulatory mode and process of some important DEGs (Dnmt1, CPS1, and endothelin-1) in the early development of the auditory system. In conclusion, we suggest that the auditory system development of L. polyactis begins at least in the neurula stage or earlier; the other three stages (tail bud stage, caudal fin fold stage, and heart pulsation stage, 28-35 HPF) mark the rapid development period. We speculate that the effect of underwater noise pollution on the embryo-larval stage probably begins even earlier.

On the formation of the pike otoliths

The purpose of the work is to describe the morphological features and time frame of otolith formation in pike embryos for subsequent use of otolith marking for juveniles released to the nature habitats. Observations of the development of eggs were carried out in aquarium conditions. The recirculating aquaculture system was used for incubation of pike eggs. The development of embryos and larvae, as well as preparations of otoliths, were examined using light microscope equipped with digital camera. The sizes of developing embryos, larvae and otoliths were measured in photographs, the scale of the images was determined using reference scale. It was found that the beginnings of hearing organs in form of otic vesicle are formed in pike embryos at the stage of organogenesis on the 6th day of development at the temperature of 9–13 °С. The detectable sign of the processes is the beginning of pigmentation of the embryo’s eyes. The formation of otoliths such as sagittae and lapilluses due to the fusion of primordial spherules and enlargement of globules continues throughout the entire period of embryonic development. By the moment of pre-larvae hatching (on the 10th day after fertilization), they have two pairs of otoliths (sagittae and lapilluses), the average size of which is 66,3±5,1 microns and 53,3±5,3, respectively. The appearance of diurnal rings on otoliths is observed before hatching, at the stage of the mobile embryo or on the first day after hatching. The data on the age of formation of otoliths and appearance of diurnal rings will be used to develop techniques of marking of pike juveniles in the hatcheries.

Acidosis defense mechanisms in the preimplantation stages of embryos in BALB/c strain mice

Regulation of intracellular pH (pHi) is an important homeostatic function of cells. There are three major pHi regulatory mechanisms: the HCO3−/Cl− exchanger (AE), which alleviates alkalosis, and the Na+/H+ exchanger (NHE) and Na+,HCO3−/Cl− exchanger (NDBCE), both of which counteract acidosis. NHE activity, which is high at the germinal vesicle stage of oocyte, is inhibited during meiotic maturation, while this inhibition is abolished when the oocyte reaches the pronuclear (PN) stage of the zygote. On the other hand, we have previously found that NDBCE performs complementary regulation against acidosis during meiotic maturation. Additionally, we found that AE activity, which is a defense mechanism against alkalosis, gradually decreases during preimplantation period of embryonic development. Considering that NHE activity is inhibited during meiotic maturation and AE activity gradually decreases during embryonic development stages, we investigated whether NHE and NDBCE activities, both of which act against acidosis, functionally change from the PN zygote to the blastocyst stage of the embryo and identified these pH-regulating proteins at the molecular level in mice of the Balb/c strain. PN zygotes, two-cell (2-c), four-cell (4-c), morula and blastocyst stage embryos were obtained from 5-8-week-old, sexually mature female Balb/c mice by using the classical superovulation procedure. pHi was recorded by using the microspectrofluorometric technique on zygotes and embryos simultaneously loaded with the pH-sensitive fluorophore, 2′,7′-Bis(2-carboxyethyl)-5(6)-carboxyfluorescein (BCECF). The activities of NHE and NDBCE were determined from the recovery curve of induced-acidosis in bicarbonate-free and bicarbonate-containing media, respectively. Specific inhibitors such as cariporide (1 μM), S3226 (1 and 10 μM), EIPA (1, 5, and 25 μM), and amiloride (1 mM) were used to functionally identify NHE isoforms, and the nonspecific inhibitor 4,4′–diisocyanatostilbene-2,2′ disulphonic acid, disodium salt (DIDS) was used to confirm NDBCE activity. The isoforms of the pHi-regulatory proteins were also identified by molecular biology using real-time PCR. We found that NHE activity was high at all embryonic stages, and differences between stages were not significant. Functional and molecular findings indicated that isoforms of NHE 1 and 5 are present in the blastocyst, whereas isoforms of NHE 1, 3, and 4 are functional at earlier embryonic stages. Although the contribution of NDBCE activity to recovery from induced-acidosis was detected at all embryonic stages, it was significant only in the PN zygote and the 2-c embryo. This finding was confirmed by molecular analysis, which detected the expression of SLC4A8 encoding NDBCE at all embryonic stages. In conclusion, NHE is an active and important defense mechanism against acidosis and is encoded by at least two protein isoforms in all stages of the Balb/c strain of mice. NDBCE has a supportive function in all embryonic stages, especially in the PN zygote and the 2-c embryo. Preimplantation stage embryos have effective mechanisms to defend against acidosis in response to their metabolic end products (increased acid load) and the acidic environment in utero.

Effects of nanoplastics exposure on ingestion, life history traits, and dimethyl sulfide production in rotifer Brachionus plicatilis

Microplastics (MPs) and nanoplastics (NPs) have gained global concern due to their detrimental effects on marine organisms. We investigated the effects of 80 nm polystyrene (PS) NPs on life history traits, ingestion, and dimethyl sulfide (DMS) and dimethylsulfoniopropionate (DMSP) production in the rotifer Brachionus plicatilis. Fluorescently labeled 80 nm PS NPs were ingested by the rotifer B. plicatilis and accumulated in the digestive tract. The lethal rates of B. plicatilis exposed to NPs were dose-dependent. High concentrations of PS NPs exposure had negative effects on developmental duration, leading to prolonged embryonic development and pre-reproductive periods, shortened reproductive period, post-reproductive period, and lifespan in B. plicatilis. High concentrations of PS NPs exposure inhibited life table demographic parameters such as age-specific survivorship and fecundity, generation time, net reproductive rate, and life expectancy. Consequently, the population of B. plicatilis was adversely impacted. Furthermore, exposure to PS NPs resulted in a reduced ingestion rate in B. plicatilis, as well as a decreased in DMS, particulate DMSP (DMSPp) concentration, and DMSP lyase activity (DLA), which exhibited a dose-response relationship. B. plicatilis grazing promoted DLA and therefore increased DMS production. PS NPs exposure caused a decline in the increased DMS induced by rotifer grazing. Our results help to understand the ecotoxicity of NPs on rotifer and their impact on the biogeochemical cycle of dimethylated sulfur compounds.

De novo genome and transcriptome assembly of Kelletia kelletii, a coastal gastropod and fisheries species exhibiting a northern range expansion

Understanding the genomic characteristics of non-model organisms can bridge research gaps between ecology and evolution. However, the lack of a reference genome and transcriptome for these species makes their study challenging. Here, we complete the first full genome and transcriptome sequence assembly of the non-model organism Kellet’s whelk, Kelletia kelletii, a marine gastropod exhibiting a poleward range expansion coincident with climate change. We used a combination of Oxford Nanopore Technologies, PacBio, and Illumina sequencing platforms and integrated a set of bioinformatic pipelines to create the most complete and contiguous genome documented among the Buccinoidea superfamily to date. Genome validation revealed relatively high completeness with low missing metazoan Benchmarking Universal Single-Copy Orthologs (BUSCO) and an average coverage of ∼70x for all contigs. Genome annotation identified a large number of protein-coding genes similar to some other closely related species, suggesting the presence of a complex genome structure. Transcriptome assembly and analysis of individuals during their period of peak embryonic development revealed highly expressed genes associated with specific Gene Ontology (GO) terms and metabolic pathways, most notably lipid, carbohydrate, glycan, and phospholipid metabolism. We also identified numerous heat shock proteins (HSPs) in the transcriptome and genome that may be related to coping with thermal stress during the sessile life history stage. A robust reference genome and transcriptome for the non-model organism K. kelletii provide resources to enhance our understanding of its ecology and evolution and potential mechanisms of range expansion for marine species facing environmental changes.

Study of the embryonic period of female crayfish egg development in different species

Freshwater crayfish farming is a promising area of production in the food market. This aquaculture industry is currently gaining popularity around the world, but given the high consumer demand, it requires modernisation. The efficiency of aquaculture production is based on the introduction of innovative methods into production processes, which are based on knowledge of biological characteristics, including reproductive capacity and the embryonic period of caviar development. The study aims to assess the reproductive quality of females and determine the incubation period of caviar, its quantity, weight, and survival rate. The study presents the results of research on the reproductive qualities and embryonic period of crayfish eggs of four species (Cherax quadricarinatus, Procambarus clarkii, Procambarus fallax forma virginalis, Cherax destructor) kept in separate closed water supply tanks at an optimal planting density of 4 individuals per 0.45 m2 . Studies have shown that the colour range of caviar and the duration of the incubation period for its maturation varies among different crayfish species. Thus, the first stage of incubation was the shortest and ranged from 2.80 (Florida crayfish) to 3.55 (destructor crayfish) days, while the second stage lasted the longest – from 13.17 to 15.80 days for Australian and broad-toed crayfish, respectively. Based on the analysis of the physiological characteristics of the female crayfish micropopulation, they were divided into quality categories, considering the following indicators: female weight, egg weight, total number of eggs, and number of eggs per 1 g of female. Females of the Australian red snapper of the excellent category was the best among all species in terms of live weight (63.0±0.67 g), egg weight (5.0±0.05 g) and total number of eggs (376.8±16.34 pcs.), the lowest similar indicators were in the marble species (16.8±0.15 g, 1.6±0.03 g, 124.5±2.66 pcs.), respectively. In terms of the number of eggs per 1 g of female weight, Florida crayfish prevailed (7.8±0.19). Instead, the destructor crayfish had intermediate results in these characteristics. The study results can be used in the economic activities of enterprises producing aquatic organisms

The Effect of Temperature on the Embryo Development of Cephalopod Sepiella japonica Suggests Crosstalk between Autophagy and Apoptosis.

Temperature is a crucial environmental factor that affects embryonic development, particularly for marine organisms with long embryonic development periods. However, the sensitive period of embryonic development and the role of autophagy/apoptosis in temperature regulation in cephalopods remain unclear. In this study, we cultured embryos of Sepiella japonica, a typical species in the local area of the East China Sea, at different incubation temperatures (18 °C, 23 °C, and 28 °C) to investigate various developmental aspects, including morphological and histological characteristics, mortality rates, the duration of embryonic development, and expression patterns of autophagy-related genes (LC3, BECN1, Inx4) and apoptosis marker genes (Cas3, p53) at 25 developmental stages. Our findings indicate that embryos in the high-temperature (28 °C) group had significantly higher mortality and embryonic malformation rates than those in the low-temperature (18 °C) group. Furthermore, high temperature (28 °C) shortened the duration of embryonic development by 7 days compared to the optimal temperature (23 °C), while low temperature (18 °C) caused a delay of 9 days. Therefore, embryos of S. japonica were more intolerant to high temperatures (28 °C), emphasizing the critical importance of maintaining an appropriate incubation temperature (approximately 23 °C). Additionally, our study observed, for the first time, that the Early blastula, Blastopore closure, and Optic vesicle to Caudal end stages were the most sensitive stages. During these periods, abnormalities in the expression of autophagy-related and apoptosis-related genes were associated with higher rates of mortality and malformations, highlighting the strong correlation and potential interaction between autophagy and apoptosis in embryonic development under varying temperature conditions.

Conjugate Variability of Signs of the Female Generative System of Scots Pine (Pinus sylvestris L.) in the Conditions of Magnesite Pollution

In the conditions of environmental pollution by emissions of magnesite production (Combined Magnesite, Satka, Chelyabinsk region), a study of the conjugate variability of signs of the female generative system of the Scots pine (Pinus sylvestris L.) was carried out. Signs with a stable connection have been identified, as well as signs whose direction of interconnection changes under the influence of aerotechnogenic pollution. Thus, the relationship of the signs characterizing the size and mass of cones is rigidly genetically determined and is not violated in conditions of a strong level of pollution. The seed productivity of the pine stands, regardless of the growing conditions, is more closely related to the survival rates of ovules in the gametophytic period than in the period of embryonic development. However, in conditions of heavy pollution, the relationship between the survival of ovules in the 1st vegetative and embryonic periods is negative, which may indicate the effective elimination of abnormal gametophytes and the release of the stand from them in conditions of pollution. The strong weakening of trees and the low availability of mineral resources in conditions of high pH of the growing medium in the zone of heavy pollution cause an increase in the negative relationship between seed productivity and seed weight to a significant level. Also, the conditions of heavy pollution “contributed” to the development of a strategy of trees for the formation of small seeds with high quality and quality indicators, seedlings developed. Only in these growing conditions, with a decrease in seed weight, the indicators of germination energy, germination percentage, and morphometric indicators of seedlings significantly increased.

Effects of Exposure Timing on cyp1a Expression, PAH Elimination, and Lipid Utilization in Lumpfish Embryos Exposed to Produced Water.

Intentional discharges of produced water from oil production platforms to the marine environment contain a complex mixture of toxicants, including polycyclic aromatic hydrocarbons (PAHs). Early life stages of fish are highly sensitive to petrogenic exposure, and short-term exposure during critical periods of embryonic development may have detrimental effects on larvae health and survival. However, why different periods are more sensitive to exposure than others are not fully understood. Three identical exposure experiments (48 h, approx. 30 μg/L tPAH, sum 42 PAHs) on lumpfish (Cyclopterus lumpus) embryos were conducted where only exposure timing was varied: 0-48 h post fertilization (hpf, starting before chorion hardening), 36-84 hpf (starting after chorion hardening), and 240-288 hpf (during organogenesis). Total PAH (tPAH) uptake at the end of exposure was 5× higher when exposed during fertilization than when exposed late (during organogenesis). The first evidence of cyp1a induction in lumpfish during embryogenesis was observed after 84 hpf. Early exposure affected lipid droplet coagulation, indicating altered lipid utilization during embryogenesis. Although no significant impacts of exposure were observed on hatching success, hatching was delayed when exposed at the latest time point. This study shows that chorion properties, lipid content, biotransformation potential, and timing of produced water exposure during lumpfish embryogenesis affected PAH uptake and elimination.

Epigenetic mechanisms of the maternal hyperhomocysteinemia influence on the placenta functional state and the offspring nervous system plasticity

According to modern concepts, the susceptibility to certain diseases, especially to cognitive and neuropsychiatric disorders, can be formed during the period of embryonic development. Adverse factors that affect the mother during pregnancy increase the risk of the pathology development in the postnatal period. Despite the relationship found between elevated maternal blood levels of the amino acid homocysteine (Hcy) and fetal brain formation impairments, as well as cognitive deficits in offspring, the role of brain plasticity in the development of these pathologies is still insufficiently studied. This review allows to be acquainted with the available data on the negative impact of hyperhomocysteinemia (HHcy) on the neural plasticity. An important aspect of the problem considered in the review is the possible influence of maternal HHcy on the offspring brain plasticity through the epigenetic mechanisms. Data on changes in intracellular methylation potential, activity of DNA methyltransferases, and DNA methylation in brain cells under the influence of HHcy are presented, and possible effects of HHcy on histone modifications and microRNA expression are considered. Since placenta plays a key role in the transport of nutrients and modulation of signals from mother to fetus, its dysfunction due to epigenetic mechanisms disturbances may affect the development of the fetal CNS. In this regard, the review presents data on the impact of maternal HHcy on the epigenetic regulation in the placenta. The data presented in the review are not only of theoretical significance, but are also of interest for understanding the role of epigenetic mechanisms in the pathogenesis of diseases for which HHcy is a risk factor (pregnancy pathologies accompanied by delayed fetal brain development, cognitive impairments in childhood and neuropsychiatric and neurodegenerative disorders later in life), as well as the search for approaches to their prevention using neuroprotectors.

Development of genetic sex markers of zig-zag eel (Mastacembelus armatus) by a NGS method

Identifying sex-specific marker with universal applicability is important for the study of unisexual reproduction and sex determination mechanism. In this study, two genetic sex markers of zig-zag eel were identified using a NGS method. Twelve potential male-specific sequences were first obtained by whole genome re-sequencing analysis of three males and three females. After PCR amplification and agarose gel electrophoresis for validation, two male-specific markers were obtained. Moreover, these markers were further verified in different populations in the Pearl River basin, and the accuracy of M2 markers was 100%. In addition, these markers were used to identify the genetic sex of different periods of embryonic development and hatching of juveniles at different time points in the cultured population, and it was found that male to female switching was common in the cultured population. Besides, we also found some embryos with YY genotype. These universal sex-specific markers will lay a good foundation for understanding of sex determination mechanism and development of all-male breeding of zig-zag eel.

Comparison of embryonic development, from HH21 to HH40, between ostrich (Struthio camelus) and chicken (Gallus gallus).

The chicken has been a representative model organism to study embryonic development in birds, however important differences exist among this class of species. As a representative of one of oldest existing clades of birds, the African ostrich (Struthio camelus), has the largest body among birds, and has two toes. Our purpose is to establish the corresponding stages in ostrich embryo development that match the well-established HH system of the chicken to facilitate comparative studies between the ostrich and other birds to better understand differences in development. Here we describe in detail the middle period of embryonic development using microscopic images and skeletal staining. We found that clear morphological differentiation between the ostrich and the chicken begins at stage 26. Bird limb cartilage first form in stage 25, while the development of the limb skeletons differs after stage 31. Calcification of limb skeletons in the chicken was completed faster. The first and second toes of the ostrich disappear at stages 36 and 38, respectively. This study should greatly aid ostrich-related developmental and morphological research and provide a reference for studying the development and evolution of avian limb skeletons, including molecular research. Questions that can now be addressed include studies into the fusion of tarsometatarsal skeleton, ossification, and digit loss.

Upper gastrointestinal duplication complicated by perforation in a child

Gastrointestinal duplications are rare congenital malformations occurring in embryonic period of development of digestive system. These abnormalities are usually found in infancy or early childhood. Clinical presentation is extremely diverse depending on dimensions, localization and type of duplication. The authors present duplication of antral and pyloric parts of the stomach, the 1st segment of the duodenum and pancreatic tail. Mother with a 6-month-old child turned to the hospital. According to the mother, the child was sick for about 3 days when episodes of periodic anxiety first appeared. Upon admission, abdominal neoplasm was suspected after ultrasound. On the second day after admission, anxiety increased. There was impairment of appetite, and the child rejected food. Abdominal asymmetry in umbilical area was observed. Considering clinical data on intestinal obstruction, emergency transverse right-sided laparotomy was performed. A tubular structure was found resembling intestinal tube was found between the stomach and transverse colon. Surgeon found duplication of antral and pyloric parts of the stomach, the 1st segment of the duodenum and its perforation. During further revision, additional pancreatic tail was diagnosed. En-bloc resection of gastrointestinal duplications was carried out. Postoperative period was uneventful. Enteral feeding was initiated after 5 days, and the patient was transferred to surgical unit. The child was discharged after 12 postoperative days.

Aneurysm of the primitive trigeminal artery: a clinical case and a literature review

Background. The primitive trigeminal artery is a fetal anastomosis connecting carotid and vertebrobasilar basins during embryonic period of development. After birth, this artery in the child is obliterated and reduced in most cases. Sometimes the obliteration does not occur and as a result the aneurysms may be formed on this artery (due to change in ordinary hemodynamics in carotid basin), as a consequence, it produces a risk of subarachnoid hemorrhage that sharply worsens prognosis of the disease outcome. The usual microsurgical treatment methods of aneurysms of such localization are of little use and are highly traumatic due to the very “low” location of the neck, because the surgery may need extended basal accesses requiring resection of skull base bones. Also, an “open” surgery produces risks of perforating arteries injury that often extend from trigeminal artery and feed the brain stem, the injury will immediately result in brain ischemic damage. That is why the preferred method for treatment of that kind of pathology may include endovascular intervention both of non‑reconstructive type employing microcoils only and those of reconstructive requiring implantation of assisting or flow‑redirecting stents.Aim. To demonstrate a case of successful treatment of patient with a primitive trigeminal artery aneurysm.Materials and methods. A woman, who was admitted to clinic with complaints of convergent strabismus, undergone surgery for large aneurysm located on primitive trigeminal artery. CT brain angiography revealed large aneurysm of primitive trigeminal artery on the right, the result was later confirmed by data of selective cerebral subtraction angiography. Taking into account oculomotor disorders in the patient, it was decided to refrain from microcoils use due to risk of the mass‑effect preservation. Under double disaggregant therapy (ticagrelor 90 mg twice daily + acetylsalicylic acid 100 mg once daily in the evening) and monitoring the functional activity of platelets, a flow‑deflecting stent was implanted into the right internal carotid artery.Results. The patient was discharged from hospital on the 1st day after the surgery and returned to work. A control angiography performed 3 years later revealed a total shutdown of the aneurysm from bloodstream as well as a partial regression of oculomotor disorders. Intravascular treatment in this situation served as an effective method of choice and made it possible to reliably turn off the aneurysm from bloodstream without impairing the functional outcome of patient’s treatment.Conclusions. It can be assumed that intravascular intervention in case of such aneurysms serves as an effective method of choice as minimally invasive and low‑traumatic surgery in the treatment of patients with that type of pathology.