Displaying publications 1 - 20 of 48 in total

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  1. Fulltext ING2 (inhibitor of growth protein-2) plays a crucial role in preimplantation development
    Zhou L, Wang P, Zhang J, Heng BC, Tong GQ
    Zygote, 2016 Feb;24(1):89-97.
    PMID: 25672483 DOI: 10.1017/S0967199414000768
    ING2 (inhibitor of growth protein-2) is a member of the ING-gene family and participates in diverse cellular processes involving tumor suppression, DNA repair, cell cycle regulation, and cellular senescence. As a subunit of the Sin3 histone deacetylase complex co-repressor complex, ING2 binds to H3K4me3 to regulate chromatin modification and gene expression. Additionally, ING2 recruits histone methyltransferase (HMT) activity for gene repression, which is independent of the HDAC class I or II pathway. However, the physiological function of ING2 in mouse preimplantation embryo development has not yet been characterized previously. The expression, localization and function of ING2 during preimplantation development were investigated in this study. We showed increasing expression of ING2 within the nucleus from the 4-cell embryo stage onwards; and that down-regulation of ING2 expression by endoribonuclease-prepared small interfering RNA (esiRNA) microinjection results in developmental arrest during the morula to blastocyst transition. Embryonic cells microinjected with ING2-specific esiRNA exhibited decreased blastulation rate compared to the negative control. Further investigation of the underlying mechanism indicated that down-regulation of ING2 significantly increased expression of p21, whilst decreasing expression of HDAC1. These results suggest that ING2 may play a crucial role in the process of preimplantation embryo development through chromatin regulation.
    Matched MeSH terms: Embryonic Development/genetics; Embryonic Development/physiology*
  2. Breeding performance and embryogenic development of three strains of Heterobranchus longifilis in Nigeria
    Alih RA, Solomon SG, Olufeagba SO, Cheikyula JO, Abol-Munafi AB, Okomoda VT
    Zygote, 2022 Feb;30(1):125-131.
    PMID: 34176523 DOI: 10.1017/S0967199421000411
    The study sought to investigate the chronology of events and timing of embryogenesis, as well as breeding performances of three strains of Heterobranchus longifilis from Nigeria. Fish samples were collected from Benue River in Makurdi, Niger River in Onitsha, and Rima River in Sokoto for this study. Induced spawning of the strains was carried out so that egg development could be tracked from fertilization to hatching using a simple microscope. The microphotographs obtained showed that the embryogenesis of the strains followed a similar pattern to those of other members of the family Clariidae, however with changes occurring in the specific timing of the sequences of events (i.e. interstrain and interspecies differences). When the different strains were compared, the study noted similarities (P > 0.05) in the overall breeding performance (except for fertilization rate), survival at different stages of development, timing of embryogenesis, and larvae characteristics. The outcomes of this study, therefore, provide baseline information on what genetic improvement of the species through strain crossing can be attempted in future studies.
    Matched MeSH terms: Embryonic Development
  3. Epitokous metamorphosis, reproductive swimming, and early development of the estuarine polychaete, Neanthes glandicincta Southern, 1921 (Annelida, Nereididae) on the east coast of the Malay Peninsula
    Azmi SS, Ibrahim YS, Angsupanich S, Sumpuntarat P, Sato M
    Zookeys, 2021;1011:1-24.
    PMID: 33551646 DOI: 10.3897/zookeys.1011.59780
    The reproductive and developmental characteristics of the nereidid polychaete, Neanthes glandicincta Southern, 1921, commonly recorded in tropical estuaries in the Indo-West Pacific, were examined from Malaysia (the mangrove area of Kuala Ibai, Terengganu) and Thailand (the Lower Songkhla Lagoon) on the east coast of the Malay Peninsula. Epitokous metamorphosis of fully mature males and females and their reproductive swimming behaviour were recorded based on ten Malaysian epitokous specimens, which were collected at night during spring tides in a period of January 2018 to March 2019. Six Thailand epitokes were obtained in February and March 2006 by the laboratory rearing of immature worms. Epitokous metamorphosis is characterised by the enlargement of eyes in both sexes, division of the body into three parts and modification of parapodia with additional lobes in the mid-body of males, and replacement of atokous chaetae in the mid-body by epitokous natatory chaetae, completely in males and incompletely in females. The diameter of coelomic unfertilised eggs in females was 100-140 µm. After fertilisation, each egg formed a jelly layer, inside which embryonic development progressed. Trochophores hatched out of the jelly layer, entering a short free-swimming larval phase followed by demersal life at the early stage of 3-chaetiger nectochaeta one day after fertilisation. Then, the larvae entered benthic life as juveniles, crawling on the bottom, at the late stage of 3-chaetiger nectochaeta two days after fertilisation. The results indicate that N. glandicincta has an annual life cycle, which is usually completed within an estuary with limited larval dispersal ability.
    Matched MeSH terms: Embryonic Development
  4. Fulltext Effect of salinity on embryo and larval development of oyster Crassostrea iredalei
    Ng, Amelia Phei Fang, Teh, Chiew Peng, Poi, Khoy Yen, Tan, Aileen Shau Hwai, Zulfigar Yasin
    Trop Life Sci Res, 2016;27(11):23-29.
    MyJurnal
    The effects of salinity on the embryonic and larvae stage of Crassostrea iredalei
    were investigated. Fertilised eggs and one day old D-larvae were subjected to salinities
    ranging from 0 to 30 ppt at temperature of 30±2°C. At salinity lower than 10 ppt, 100%
    mortality was observed. For embryo development, the highest survival was observed at
    salinity 25 ppt with 80.9±2.2% survival with no significant difference compared to 15 and
    30 ppt. Shell height and length were both greatest at salinity 30 ppt. Throughout the 11
    days culture, the highest larval survival occurred at salinity 15 ppt with no significant
    difference compared to all other salinities except 10 ppt. Larval shell sizes showed no
    significant differences between salinities, except for 10 ppt. Optimum culture condition for
    larvae growth are salinities ranging from 15 to 30 ppt whereby the larval of this species
    can tolerate wider range of salinity compared to other oyster species and thus, making it a
    competitive species to be cultured.
    Matched MeSH terms: Embryonic Development
  5. Increasing glucose in KSOMaa basal medium on culture Day 2 improves in vitro development of cloned caprine blastocysts produced via intraspecies and interspecies somatic cell nuclear transfer
    Kwong PJ, Abdullah RB, Wan Khadijah WE
    Theriogenology, 2012 Sep 1;78(4):921-9.
    PMID: 22704387 DOI: 10.1016/j.theriogenology.2012.04.009
    This study was conducted to evaluate the efficiency of potassium simplex optimization medium with amino acids (KSOMaa) as a basal culture medium for caprine intraspecies somatic cell nuclear transfer (SCNT) and caprine-bovine interspecies somatic cell nuclear transfer (iSCNT) embryos. The effect of increased glucose as an energy substrate for late stage development of cloned caprine embryos in vitro was also evaluated. Enucleated caprine and bovine in vitro matured oocytes at metaphase II were reconstructed with caprine ear skin fibroblast cells for the SCNT and iSCNT studies. The cloned caprine and parthenogenetic embryos were cultured in either KSOMaa with 0.2 mM glucose for 8 days (Treatment 1) or KSOMaa for 2 days followed by KSOMaa with additional glucose at a final concentration of 2.78 mM for the last 6 days (Treatment 2). There were no significant differences in the cleavage rates of SCNT (80.7%) and iSCNT (78.0%) embryos cultured in KSOMaa medium. Both Treatment 1 and Treatment 2 could support in vitro development of SCNT and iSCNT embryos to the blastocyst stage. However, the blastocyst development rate of SCNT embryos was significantly higher (P < 0.05) in Treatment 2 compared to Treatment 1. Increasing glucose for later stage embryo development (8-cell stage onwards) during in vitro culture (IVC) in Treatment 2 also improved both caprine SCNT and iSCNT embryo development to the hatched blastocyst stage. In conclusion, this study shows that cloned caprine embryos derived from SCNT and iSCNT could develop to the blastocyst stage in KSOMaa medium supplemented with additional glucose (2.78 mM, final concentration) and this medium also supported hatching of caprine cloned blastocysts.
    Matched MeSH terms: Embryonic Development/drug effects*; Embryonic Development/physiology
  6. Prolonging the interval from ovarian hyperstimulation to laparoscopic ovum pick-up improves oocyte yield, quality, and developmental competence in goats
    Abdullah RB, Liow SL, Rahman AN, Chan WK, Wan-Khadijah WE, Ng SC
    Theriogenology, 2008 Sep 15;70(5):765-71.
    PMID: 18579196 DOI: 10.1016/j.theriogenology.2008.04.052
    The objective was to evaluate the effect of the interval between ovarian hyperstimulation and laparoscopic ovum pick-up (LOPU) on quality and developmental competence of goat oocytes before and after in vitro maturation (IVM) and intracytoplasmic sperm injection (ICSI). Estrus was synchronized with an intravaginal insert containing 0.3g progesterone (CIDR) for 10d, combined with a luteolytic treatment of 125 microg cloprostenol 36 h prior to CIDR removal. Ovaries were hyperstimulated with 70 mg FSH and 500 IU hCG given im 36, 60, or 72 h prior to LOPU (n=15, 16, and 7 does, respectively). For these groups, oocyte retrieval rates (mean+/-S.E.M.) were 24.7+/-2.9, 54.5+/-4.7, and 82.8+/-4.6% (P<0.001), and the proportions of cumulus-oocyte complexes (COC) with more than five layers of cumulus cells were 29.7+/-8.3, 37.6+/-6.9, and 37.3+/-7.0% (P<0.001). The proportion of IVM oocytes was highest at 72 h (82.1+/-2.8%; P<0.05), with no significant difference between 36 and 60 h (57.3+/-8.9% and 69.0+/-8.4%). Cleavage rates of ICSI embryos were 4.2+/-4.2, 70.9+/-8.4, and 78.9+/-8.2% with LOPU 36, 60, and 72 h post FSH/hCG (P<0.01), with a lower proportion of Grade-A embryos (P<0.05) following LOPU at 36 h compared to 60 and 72 h (29.7+/-8.3%, 37.6+/-6.9%, and 37.3+/-7.0%). In summary, a prolonged interval from FSH/hCG to LOPU improved oocyte retrieval rate and oocyte quality. Therefore, under the present conditions, LOPU 60 or 72 h after FSH/hCG optimized yields of good-quality oocytes for IVM and embryo production in goats.
    Matched MeSH terms: Embryonic Development
  7. Fulltext Determination of suitable microspore stage and callus induction from anthers of kenaf (Hibiscus cannabinus L.)
    Ibrahim AM, Kayat FB, Hussin ZE, Susanto D, Ariffulah M
    ScientificWorldJournal, 2014;2014:284342.
    PMID: 24757416 DOI: 10.1155/2014/284342
    Kenaf (Hibiscus cannabinus L.) is one of the important species of Hibiscus cultivated for fiber. Availability of homozygous parent lines is prerequisite to the use of the heterosis effect reproducible in hybrid breeding. The production of haploid plants by anther culture followed by chromosome doubling can be achieved in short period compared with inbred lines by conventional method that requires self pollination of parent material. In this research, the effects of the microspore developmental stage, time of flower collection, various pretreatments, different combinations of hormones, and culture condition on anther culture of KB6 variety of Kenaf were studied. Young flower buds with immature anthers at the appropriate stage of microspore development were sterilized and the anthers were carefully dissected from the flower buds and subjected to various pretreatments and different combinations of hormones like NAA, 2,4-D, Kinetin, BAP, and TDZ to induce callus. The best microspore development stage of the flower buds was about 6-8 mm long collected 1-2 weeks after flower initiation. At that stage, the microspores were at the uninucleate stage which was suitable for culture. The best callus induction frequency was 90% in the optimized semisolid MS medium fortified with 3.0 mg/L BAP + 3.0 mg/L NAA.
    Matched MeSH terms: Embryonic Development/drug effects; Embryonic Development/physiology*
  8. Fulltext Diverse roles of prostaglandins in blastocyst implantation
    Salleh N
    ScientificWorldJournal, 2014;2014:968141.
    PMID: 24616654 DOI: 10.1155/2014/968141
    Prostaglandins (PGs), derivatives of arachidonic acid, play an indispensable role in embryo implantation. PGs have been reported to participate in the increase in vascular permeability, stromal decidualization, blastocyst growth and development, leukocyte recruitment, embryo transport, trophoblast invasion, and extracellular matrix remodeling during implantation. Deranged PGs syntheses and actions will result in implantation failure. This review summarizes up-to-date literatures on the role of PGs in blastocyst implantation which could provide a broad perspective to guide further research in this field.
    Matched MeSH terms: Embryonic Development/drug effects
  9. Hedgehog signalling molecule, SMO is a poor prognostic marker in bladder cancer
    Mohd Ariffin K, Abd Ghani F, Hussin H, Md Said S, Yunus R, Veerakumarasivam A, et al.
    Malays J Pathol, 2021 Apr;43(1):49-54.
    PMID: 33903305
    INTRODUCTION: Hedgehog (HH) pathway is an important signalling cascade for growth and patterning during embryonic development. Constitutive activation of Hedgehog pathway can be found in various types of malignancies including medulloblastoma, basal cell carcinoma, gastrointestinal, breast, pancreatic, prostate cancer and leukaemia. Little is known about the expression and role of Hedgehog signalling in bladder cancer.

    MATERIALS AND METHODS: The purpose of this study was to investigate the immunohistochemical expression of SMO in 112 bladder cancer cases and determine their association with demographic and clinicopathological parameters. Bladder cancer tissues were obtained from the Hospital Kuala Lumpur.

    RESULTS: SMO was expressed in the cytoplasm of all cases of bladder cancer. 6 cases (5.4%) showed low expression, while 106 cases (94.6%) showed high expression. Positive expression of SMO protein was correlated with a few variables which include grade and stage of tumour, lymph node metastasis and distant metastasis. SMO expression showed statistically significant association with higher grade (p=0.001) and higher stage (p=0.042) of bladder cancer. SMO expression also showed borderline association with lymph node metastasis (p=0.056).

    CONCLUSION: These findings indicate that SMO expression may be a poor prognostic marker in bladder cancer.

    Matched MeSH terms: Embryonic Development
  10. Fulltext MiR-3099 is Overexpressed in Differentiating 46c Mouse Embryonic Stem Cells upon Neural Induction
    Zainal Abidin S, Abbaspourbabaei M, Ntimi CM, Siew WH, Pike-See C, Rosli R, et al.
    Malays J Med Sci, 2014 Dec;21(Spec Issue):27-33.
    PMID: 25941460 MyJurnal
    MicroRNAs (miRNAs) have a crucial role in gene expression regulation and protein synthesis, especially in the central nervous system. In developing mouse embryos a novel miRNA, miR-3099, is highly expressed, particularly in the central nervous system. This study aims to determine the expression of miR-3099 during cellular differentiation of 46C mouse embryonic stem cells after neural induction with N2/B27 medium.
    Matched MeSH terms: Embryonic Development
  11. Fulltext Signaling pathways promoting epithelial mesenchymal transition in oral submucous fibrosis and oral squamous cell carcinoma
    Shetty SS, Sharma M, Fonseca FP, Jayaram P, Tanwar AS, Kabekkodu SP, et al.
    Jpn Dent Sci Rev, 2020 Nov;56(1):97-108.
    PMID: 32874377 DOI: 10.1016/j.jdsr.2020.07.002
    Epithelial-mesenchymal transition (EMT) is a critical process that occurs during the embryonic development, wound healing, organ fibrosis and the onset of malignancy. Emerging evidence suggests that the EMT is involved in the invasion and metastasis of cancers. The inflammatory reaction antecedent to fibrosis in the onset of oral submucous fibrosis (OSF) and the role of EMT in its malignant transformation indicates a hitherto unexplored involvement of EMT. This review focuses on the role of EMT markers which are regulators of the EMT mediated complex network of molecular mechanisms involved in the pathogenesis of OSF and OSCC. Further the gene enrichment analysis and pathway analysis supports the association of the upregulated and downregulated genes in various EMT regulating pathways.
    Matched MeSH terms: Embryonic Development
  12. Postnatal growth rates covary weakly with embryonic development rates and do not explain adult mortality probability among songbirds on four continents
    Martin TE, Oteyza JC, Mitchell AE, Potticary AL, Lloyd P
    Am Nat, 2015 Mar;185(3):380-9.
    PMID: 25674692 DOI: 10.1086/679612
    Growth and development rates may result from genetic programming of intrinsic processes that yield correlated rates between life stages. These intrinsic rates are thought to affect adult mortality probability and longevity. However, if proximate extrinsic factors (e.g., temperature, food) influence development rates differently between stages and yield low covariance between stages, then development rates may not explain adult mortality probability. We examined these issues based on study of 90 songbird species on four continents to capture the diverse life-history strategies observed across geographic space. The length of the embryonic period explained little variation (ca. 13%) in nestling periods and growth rates among species. This low covariance suggests that the relative importance of intrinsic and extrinsic influences on growth and development rates differs between stages. Consequently, nestling period durations and nestling growth rates were not related to annual adult mortality probability among diverse songbird species within or among sites. The absence of a clear effect of faster growth on adult mortality when examined in an evolutionary framework across species may indicate that species that evolve faster growth also evolve physiological mechanisms for ameliorating costs on adult mortality. Instead, adult mortality rates of species in the wild may be determined more strongly by extrinsic environmental causes.
    Matched MeSH terms: Embryonic Development
  13. Fulltext Surgical and embryological perspective of a big loop of internal carotid artery extending laterally beyond internal jugular vein
    Nayak SB, Shetty SD
    Surg Radiol Anat, 2021 Mar;43(3):413-416.
    PMID: 33231750 DOI: 10.1007/s00276-020-02619-z
    Knowledge of variations of the internal carotid artery is significant to surgeons and radiologists. The internal carotid artery normally runs a straight course in the neck. Its anomalies can lead to its iatrogenic injuries. We report a case of a large loop of the internal carotid artery in a male cadaver aged about 75 years. The common carotid artery terminated by dividing it into the external carotid artery and internal carotid arteries at the level of the upper border of the thyroid cartilage. From the level of origin, the internal carotid artery coursed upwards, backwards and laterally, and formed a large loop behind the internal jugular vein. The variation was found on the left side of the neck and was unilateral. The uncommon looping of the internal carotid artery might result in altered blood flow to the brain and may lead to misperceptions in surgical, imaging, and invasive procedures.
    Matched MeSH terms: Embryonic Development
  14. Fulltext The effects of Piper sarmentosum aqueous extracts on zebrafish (Danio rerio) embryos and caudal fin tissue regeneration
    Zainol Abidin IZ, Fazry S, Jamar NH, Ediwar Dyari HR, Zainal Ariffin Z, Johari AN, et al.
    Sci Rep, 2020 08 25;10(1):14165.
    PMID: 32843675 DOI: 10.1038/s41598-020-70962-7
    In Malaysia, Piper sarmentosum or 'kaduk' is commonly used in traditional medicines. However, its biological effects including in vivo embryonic toxicity and tissue regenerative properties are relatively unknown. The purpose of this study was to determine zebrafish (Danio rerio) embryo toxicities and caudal fin tissue regeneration in the presence of P. sarmentosum aqueous extracts. The phytochemical components and antioxidant activity of the extract were studied using GC-MS analysis and DPPH assay, respectively. Embryo toxicity tests involving survival, heartbeat, and morphological analyses were conducted to determine P. sarmentosum extract toxicity (0-60 µg/mL); concentrations of 0-400 µg/mL of the extract were used to study tissue regeneration in the zebrafish caudal fin. The extract contained several phytochemicals with antioxidant activity and exhibited DPPH scavenging activity (IC50 = 50.56 mg/mL). Embryo toxicity assays showed that a concentration of 60 μg/mL showed the highest rates of lethality regardless of exposure time. Slower embryogenesis was observed at 40 µg/mL, with non-viable embryos first detected at 50 µg/mL. Extracts showed significant differences (p 
    Matched MeSH terms: Embryonic Development/drug effects*
  15. Diabetes alters the mRNA expression of insulin-like growth factors and their receptors in the mouse fallopian tube and uterus during the preimplantation stages
    Zakaria R, Rajikin MH, Yaacob NS, Nor NM
    Reprod Biol, 2007 Mar;7(1):41-53.
    PMID: 17435832
    The possible role of insulin-like growth factors (IGFs) and their receptors (IGFRs) in the pathogenesis of diabetic embryopathy was investigated. Sexually mature female ICR mice of 6-8 weeks old were made diabetic by a single intraperitoneal injection with 200 mg/kg streptozotocin ten days prior to mating. Fallopian tubes and uterine tissues were obtained from the superovulated diabetic and normal mice 48, 72 and 96 hours following human chorionic gonadotropin (hCG) injection. The mRNA expression of IGF-1 and IGF-2 as well as their receptors was determined in the tissues using Real-time Polymerase Chain Reaction (Real-time PCR). The mRNA expression of IGF-1 in the fallopian tube and uterus of the diabetic mice was significantly lower 72 and 96 hours after hCG treatment, respectively, as compared to the controls. The mRNA expression of IGF-1R at 96 hours post-hCG treatment was significantly higher in the fallopian tube and lower in the uterus of the diabetic mice as compared to the controls. The mRNA expression IGF-2 in the fallopian tube was significantly higher 48 and 96 hours after hCG treatment, but was lower in the uterus of diabetic mice 96 hours after hCG treatment as compared to controls. The mRNA expression of IGF-2R in the diabetic mice was significantly higher 48 and 96 hours (the fallopian tube) and 48 hours (uterus) after hCG treatments as compared to the controls. In conclusion, an alteration in mRNA expression of IGFs and their receptors in the diabetic mice as observed in this study could possibly result in diabetic embryopathy.
    Matched MeSH terms: Embryonic Development/physiology*
  16. Comparison of in vitro developmental competence of cloned caprine embryos using donor karyoplasts from adult bone marrow mesenchymal stem cells vs ear fibroblast cells
    Kwong PJ, Nam HY, Wan Khadijah WE, Kamarul T, Abdullah RB
    Reprod. Domest. Anim., 2014 Apr;49(2):249-53.
    PMID: 24456113 DOI: 10.1111/rda.12262
    The aim of this study was to produce cloned caprine embryos using either caprine bone marrow-derived mesenchymal stem cells (MSCs) or ear fibroblast cells (EFCs) as donor karyoplasts. Caprine MSCs were isolated from male Boer goats of an average age of 1.5 years. To determine the pluripotency of MSCs, the cells were induced to differentiate into osteocytes, chondrocytes and adipocytes. Subsequently, MSCs were characterized through cell surface antigen profiles using specific markers, prior to their use as donor karyoplasts for nuclear transfer. No significant difference (p > 0.05) in fusion rates was observed between MSCs (87.7%) and EFCs (91.3%) used as donor karyoplasts. The cleavage rate of cloned embryos derived with MSCs (87.0%) was similar (p > 0.05) to those cloned using EFCs (84.4%). However, the in vitro development of MSCs-derived cloned embryos (25.3%) to the blastocyst stage was significantly higher (p < 0.05) than those derived with EFCs (20.6%). In conclusion, MSCs could be reprogrammed by caprine oocytes, and production of cloned caprine embryos with MSCs improved their in vitro developmental competence, but not in their fusion and cleavage rate as compared to cloning using somatic cells such as EFCs.
    Matched MeSH terms: Embryonic Development
  17. Fulltext Embryos of the viviparous dermapteran, Arixenia esau develop sequentially in two compartments: terminal ovarian follicles and the uterus
    Tworzydlo W, Kisiel E, Bilinski SM
    PLoS One, 2013;8(5):e64087.
    PMID: 23667700 DOI: 10.1371/journal.pone.0064087
    Three main reproductive strategies have been described among insects: most common oviparity, ovoviviparity and viviparity. In the latter strategy, the embryonic development takes place within the body of the mother which provides gas exchange and nutrients for embryos. Here we present the results of histological and EM analyses of the female reproductive system of the viviparous earwig, Arixenia esau, focusing on all the modifications related to the viviparity. We show that in the studied species the embryonic development consists of two "physiological phases" that take place in two clearly disparate compartments, i.e. the terminal ovarian follicle and the uterus. In both compartments the embryos are associated with synthetically active epithelial cells. We suggest that these cells are involved in the nourishment of the embryo. Our results indicate that viviparity in arixeniids is more complex than previously considered. We propose the new term "pseudoplacento-uterotrophic viviparity" for this unique two-phase reproductive strategy.
    Matched MeSH terms: Embryonic Development/physiology*
  18. Fulltext Oviparous elasmobranch development inside the egg case in 7 key stages
    Musa SM, Czachur MV, Shiels HA
    PLoS One, 2018;13(11):e0206984.
    PMID: 30399186 DOI: 10.1371/journal.pone.0206984
    Embryological stages of oviparous elasmobranch during development can be difficult to identify, requiring magnification and/or fixation of an anaesthetized embryo. These restrictions are poorly suited for monitoring the development of living elasmobranchs inside their egg cases. There are two major aims of this study. The first was to observe elasmobranch embryonic development non-invasively and produce a non-invasive developmental key for identifying the life stages for an elasmobranch inside the egg case. To this end, 7 key developmental stages were identified for the greater spotted catshark, Scyliorhinus stellaris, and are provided here with diagrams from multiple perspectives to demonstrate the key features of each stage. The physiological and ecological relevance of each stage are discussed in terms of structure and function for embryonic survival in the harsh intertidal zone. Also discussed is the importance of the egg case membrane and the protective embryonic jelly. The second aim of the study was to understand the applicability of the 7 developmental stages from S. stellaris to other oviparous elasmobranchs. Thus, changes in embryonic body size and egg yolk volume at each stage were measured and compared with those of the closely related, lesser spotted catshark, Scyliorhinus canicula. We find nearly identical growth patterns and yolk consumption patterns in both species across the 7 developmental stages. Thus, although the 7 developmental stages have been constructed in reference to the greater spotted catshark, we suggest that it can be applied to other oviparous elasmobranch species with only minor modification.
    Matched MeSH terms: Embryonic Development*
  19. Fulltext Expression and DNA methylation of SERK, BBM, LEC2 and WUS genes in in vitro cultures of Boesenbergia rotunda (L.) Mansf
    Karim R, Tan YS, Singh P, Khalid N, Harikrishna JA
    Physiol Mol Biol Plants, 2018 Sep;24(5):741-751.
    PMID: 30150851 DOI: 10.1007/s12298-018-0566-8
    The process of somatic embryogenesis and plant regeneration involve changes in gene expression and have been associated with changes in DNA methylation. Here, we report the expression and DNA methylation patterns of SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK), BABY BOOM (BBM), LEAFY COTYLEDON 2 (LEC2) and WUSCHEL (WUS) in meristematic block of newly emerged shoots from rhizome, embryogenic and non-embryogenic calli, prolonged cell suspension culture, ex vitro leaf, and in vitro leaf of regenerated plants of Boesenbergia rotunda. Among all seven samples, based on qRT-PCR, the highest level of expression of SERK, BBM and LEC2 was in embryogenic callus, while WUS was most highly expressed in meristematic block tissue followed by embryogenic callus. Relatively lower expression was observed in cell suspension culture and watery callus for SERK, LEC2 and WUS and in in vitro leaf for BBM. For gene specific methylation determined by bisulfite sequencing data, embryogenic callus samples had the lowest levels of DNA methylation at CG, CHG and CHH contexts of SERK, LEC2 and WUS. We observed negative correlation between DNA methylation at the CG and CHG contexts and the expression levels of SERK, BBM, LEC2 and WUS. Based on our results, we suggest that relatively higher expression and lower level of DNA methylation of SERK, BBM, LEC2 and WUS are associated with somatic embryogenesis and plant regeneration in B. rotunda.
    Matched MeSH terms: Embryonic Development
  20. Fulltext Toxicity assessment of gallic acid loaded graphene oxide (GAGO) nano-formulation in zebrafish (Danio Rerio) embryos
    Ahmad Ashraful Hadi Abdul Ghafor, Nurhuda Elias, Suhaili Shams, Faizah Md Yasin, Sarchio, Seri Narti Edayu
    Pertanika Journal of Science & Technology, 2020;28(1):311-326.
    MyJurnal
    Gallic acid (GA) is a phenolic compound found in almost all plants and has been reported to possess powerful health benefits such as anti-oxidant, anti-inflammatory, anti-cancer, and anti-diabetic properties. However, GA suffers a short half-life when administered in vivo. Recent studies have employed graphene oxide (GO), a biocompatible and cost-effective graphene derivative, as a nanocarrier for GA. However, the toxicity effect of this formulated nano-compound has not been fully studied. Thus, the present study aims to evaluate the toxicity and teratogenicity of GA loaded GO (GAGO) against zebrafish embryogenesis to further advance the development of GA as a therapeutic agent. GAGO was exposed to zebrafish embryos (n ≥ 10; 24hr post fertilization (hpf)) at different concentrations (0-500 μg/ml). The development of zebrafish was observed and recorded twice daily for four days. The toxicity of pure GO and GA was also observed at similar concentrations. Distilled water was used as control throughout the experiment. A significantly high mortality rate, delayed hatching rate and low heartbeat were recorded in embryos exposed to GO at concentrations of ≥ 150 μg/ml at 48 hr (p
    Matched MeSH terms: Embryonic Development
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