Displaying publications 1 - 20 of 42 in total

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  1. Sabetian S, Shamsir MS
    J. Membr. Biol., 2017 04;250(2):133-144.
    PMID: 28280854 DOI: 10.1007/s00232-017-9954-1
    Complete elucidation of fertilization process at molecular level is one of the unresolved challenges in sexual reproduction studies, and understanding the molecular mechanism is crucial in overcoming difficulties in infertility and unsuccessful in vitro fertilization. Sperm-oocyte interaction is one of the most remarkable events in fertilization process, and deficiency in protein-protein interactions which mediate this interaction is a major cause of unexplained infertility. Due to detection of how the various defects of sperm-oocyte interaction can affect fertilization failure, different experimental methods have been applied. This review summarizes the current understanding of sperm-egg interaction mechanism during fertilization and also accumulates the different types of sperm-egg interaction abnormalities and their association with infertility. Several detection approaches regarding sperm-egg protein interactions and the associated defects are reviewed in this paper.
    Matched MeSH terms: Oocytes/metabolism; Oocytes/physiology
  2. Yang Mohsin WS, Abdullah Chue NS, Abdul Hamid F, Abu MA, Othman S, Mat Jin N, et al.
    Int J Environ Res Public Health, 2022 Sep 29;19(19).
    PMID: 36231691 DOI: 10.3390/ijerph191912391
    INVOcell is considered an alternative to conventional IVF proposed for intravaginal embryo culture; however, implementation is still low because evidence is scanty regarding its outcome and, most importantly, the device's user satisfaction. Thus, we aim to compare the embryo outcome of sibling oocytes following INVOcell culture with conventional IVF (cIVF) by assessing its clinical outcome (fertilization, blastulation rate, and good embryo quality) and the user satisfaction evaluation based on a local validation questionnaire. A prospective study was done at a university-setting hospital for 12 months (July 2021-2022). The oocytes collected were divided into INVOcell and cIVF groups equally. Inclusion criteria included <40 years old and body mass index (BMI) < 30 kg/m2. The pre- and post-satisfaction questionnaires were assessed. In total, 23 women were included following standard controlled ovarian stimulation (COS). The mean age was 32.9, and the mean BMI was 24.9 kg/m2. Most of them suffered from tubal factors. A total of 252 oocytes were collected and incubated accordingly (cIVF; 138, INVOcell; 114). The blastulation rate was superior in the INVOcell group (p = 0.16); otherwise, the fertilization rate and good embryo quality were not significantly different between both methods (p > 0.05). Overall, women were satisfied with the INVOcell device as they were adequately advised, follow-up was scheduled, and the lowest score was obtained for all side effects of the device. Although both methods produce similar fertilization rates and good-quality embryos, the blastulation rates were better in the INVOcell group. Functionally, it is a user-friendly device and tolerable. Therefore, INVOcell can be used as an alternative method for reproductive treatment in carefully selected patients without jeopardizing the IVF outcomes.
    Matched MeSH terms: Oocytes*
  3. Zhang Y, Sun L, Zhang D, Gao Y, Ma H, Xue Y, et al.
    Ecotoxicol Environ Saf, 2023 Nov 01;266:115561.
    PMID: 37837697 DOI: 10.1016/j.ecoenv.2023.115561
    Butylparaben is an ubiquitous environmental endocrine disruptor, that is commonly used in cosmetics and personal care product due to its anti-microbial properties. Butylparaben has been shown to cause developmental toxicity, endocrine and metabolic disorders and immune diseases. However, little is known about the impact on female fertility, especially oocyte quality. In the present study, we reported that butylparaben influenced female fertility by showing the disturbed oocyte meiotic capacity and fertilization potential. Specifically, butylparaben results in the oocyte maturation arrest by impairing spindle/chromosome structure and microtubule stability. Besides, butylparaben results in fertilization failure by impairing the dynamics of Juno and ovastacin and the sperm binding ability. Last, single-cell transcriptome analysis showed that butylparaben-induced oocyte deterioration was caused by mitochondrial dysfunction, which led to the accumulation of ROS and occurrence of apoptosis. Collectively, our study indicates that mitochondrial dysfunction and redox perturbation is the major cause of the weakened female fertility expoesd to butylparaben.
    Matched MeSH terms: Oocytes/metabolism
  4. Pan K, Zhu B, Wang L, Guo Q, Shu-Chien AC, Wu X
    PMID: 37852318 DOI: 10.1016/j.cbpa.2023.111535
    The 1-acylglycerol-3-phosphate acyltransferase (AGPAT) acts as a crucial enzyme in the process of triacylglycerol (TAG) synthesis, enabling the acylation of lysophosphatidic acid (LPA) into phosphatidic acid (PA). In order to decode the distinctive roles of AGPAT isoforms in the TAG production pathway, three AGPAT isoforms were detected for the first time in the Chinese mitten crab Eriocheir sinensis (Es-agpat2, Es-agpat3, and Es-agpat4). The mRNA levels of Es-agpat2 and Es-agpat4 demonstrated a conspicuous presence in the hepatopancreas, with subsequent high levels in the heart, muscle, and thoracic ganglion. On the other hand, the thoracic ganglion exhibited abundant levels of Es-agpat3, while other tissues recorded relatively low expression levels. Observing the molting cycle of E. sinensis, the hepatopancreas showed minimum expression levels of Es-agpat2 and Es-agpat4 at stage A/B. A peak at stage C was noted, which was then followed by a gradual drop until stage E. For the ovarian development cycle, stage II witnessed the maximum expression level of Es-agpat2 and Es-agpat4, succeeded by a sharp fall in stage III. After this, there was an increasing trend from stage III up to stage V. Expression of Es-agpat3 in the hepatopancreas was consistently lower than Es-agpat2 and Es-agpat4 during either the molting or ovarian development. However, in terms of ovarian expression, Es-agpat3 outperformed Es-agpat2 and Es-agpat4. It exhibited a steep increase in expression, peaking at stage II and subsequently diminishing. In situ hybridization (ISH) revealed that in stages II and IV hepatopancreas, Es-agpat4-mRNA was primarily located in fibrillar cells (F cell) and resorptive cells (R cell), with no signal from Es-agpat3. During stage II of ovarian development, both Es-agpat3-mRNA and Es-agpat4-mRNA were located in the cytoplasm of previtellogenic oocyte (PRO) and endogenous vitellogenic oocyte (EN), with no expression at stage IV. Additionally, the silencing of Es-agpat2 and Es-agpat4 caused a downward trend in the expression levels of all subsequent genes in the E. sinensis TAG synthesis pathway. To sum up, these findings suggest that the three Es-agpats may have unique functions in TAG synthesis during either the molting process or ovarian maturation of E. sinensis.
    Matched MeSH terms: Oocytes/metabolism
  5. Amin-Safwan A, Mardhiyyah MP, Izzah-Syafiah MA, Muhd-Farouk H, Manan H, Mahsol HH, et al.
    Data Brief, 2019 Oct;26:104426.
    PMID: 31534993 DOI: 10.1016/j.dib.2019.104426
    This article investigated how crabs responded to different culture salinities through ovarian maturation stages using combination of external morphology (ovarian coloration and gonadosomatic index), and histological assessment (oocyte structures and diameter sizes). A total of sixty immature crabs were sampled from coastal water of Setiu Wetlands, Kuala Nerus, Terengganu, Peninsular Malaysia, and were introduced to limb autotomy technique in order to induce molt. Crabs were reared until successfully molted, and leaves prior to hardened shell, before proceed with salinities acclimatization prior to salinity treatments (10, 20 and 30 ppt). Five crabs were randomly selected every 15 days throughout 60-day of culture (Day 15, 30, 45 and 60) for the assessment. The different between each ovarian maturation stages was recorded based on the color appearances, and Kruskal-Wallis analysis were done between gonadosomatic index and oocyte diameter sizes with different salinity treatments. Part of the data is associated with the recent articles [1], [2] and provided here as raw data of Supplementary materials.
    Matched MeSH terms: Oocytes
  6. Chin AHB, Sandhu S, Caughey L, Ahmad MF, Peate M
    Hum Fertil (Camb), 2023 Dec;26(2):385-397.
    PMID: 37177817 DOI: 10.1080/14647273.2023.2209831
    Upon legalization of social egg freezing in Singapore from 2023 onwards, compulsory pre-procedure counselling is mandated for all prospective patients to enable informed choice about whether to undergo the procedure. Being a newly introduced medical procedure in Singapore, there are currently no clear directives on what pre-procedure counselling for elective egg freezing should entail. Due to pervasive media and internet influences, prospective egg freezing patients could be misled into believing that the procedure represents a guaranteed path to future motherhood, contrary to statements by professional bodies such as the American Society for Reproductive Medicine (ASRM) and the British Fertility Society (BFS). Hence, comprehensive counselling is recommended to provide women with evidence-based information (e.g. success rates of social egg freezing for women of their age) to ensure they make informed decisions and to avoid possible decision regret. For this purpose, a systematic protocol and methodology for pre-procedure counselling of women considering elective egg freezing was developed, incorporating flowcharts and decision trees that are specifically tailored to the unique sociocultural values and legal restrictions in Singapore. Questions relating to the why, what, how, where and when of the egg freezing procedure should be addressed, which could serve as a roadmap to facilitate informed decision-making by women considering elective egg freezing.
    Matched MeSH terms: Oocytes
  7. Adebiyi FA, Siraj SS, Harmin SA, Christianus A
    J Exp Zool A Ecol Genet Physiol, 2011 Nov 1;315(9):536-43.
    PMID: 21898849 DOI: 10.1002/jez.702
    Hemibagrus nemurus is a riverine catfish with high economic and nutritive values. Investigations on ovarian development of this fish were carried out to determine the mode of ovarian development and describe the oocyte developmental stages. Histological studies were done on ovaries using light microscopy and scanning electron microscopy. Fish were sampled monthly for a period of six months (August 2009 to January 2010). The mean oocyte diameter (OD) ranged from 871 ± 161.41 µm to 1,167 ± 26.77 µm and the highest OD was in November. Oocyte size-frequency distribution showed a polymodal distribution. The mean gonadosomatic index (GSI) ranged from 1.14 ± 0.87% to 7.06 ± 1.40% and highest GSI was in November. The ovaries exhibited three phases of oocyte growth, which were primary growth, secondary growth and maturation phases. Based on histological criteria, the oocyte developmental stages were divided into seven stages as chromatin nucleolar, early perinucleolar, late perinucleolar, cortical alveolar, vitellogenesis, mature oocyte and germinal vesicle migration stages. All the seven stages of oocyte development were observed in the ovaries. Oogonia were always present throughout the developmental stages. The ovaries had more than two stages of oocyte development. This is the first report on the mode of ovarian development of H. nemurus. These findings indicated that H. nemurus has asynchronous mode of ovarian development and is capable of spawning several times in a year under favourable conditions.
    Matched MeSH terms: Oocytes/cytology; Oocytes/growth & development*
  8. Darbandi S, Darbandi M, Khorram Khorshid HR, Sadeghi MR, Agarwal A, Sengupta P, et al.
    Reprod Biol Endocrinol, 2017 Oct 02;15(1):77.
    PMID: 28969648 DOI: 10.1186/s12958-017-0292-z
    BACKGROUND: Ooplasmic transfer (OT) technique or cytoplasmic transfer is an emerging technique with relative success, having a significant status in assisted reproduction. This technique had effectively paved the way to about 30 healthy births worldwide. Though OT has long been invented, proper evaluation of the efficacy and risks associated with this critical technique has not been explored properly until today. This review thereby put emphasis upon the applications, efficacy and adverse effects of OT techniques in human.

    MAIN BODY: Available reports published between January 1982 and August 2017 has been reviewed and the impact of OT on assisted reproduction was evaluated. The results consisted of an update on the efficacy and concerns of OT, the debate on mitochondrial heteroplasmy, apoptosis, and risk of genetic and epigenetic alteration.

    SHORT CONCLUSION: The application of OT technique in humans demands more clarity and further development of this technique may successfully prove its utility as an effective treatment for oocyte incompetence.

    Matched MeSH terms: Oocytes/cytology*; Oocytes/transplantation
  9. Rajikin MH, Yusoff M, Abdullah RB
    Theriogenology, 1994 Nov 01;42(6):1003-16.
    PMID: 16727604
    The structure and distribution of organelles within developing goat oocytes at various stages of incubation were studied. In oocytes with 5 or more layers of cumulus cells, at 0 h of incubation, the zona pellucida had developed although zonation was not evident. Lipid bodies were present but no mitochondria were observed. At 20 h, the zona pellucida had differentiated into thicker and thinner regions. Clusters of membrane-bound electron-transparent bodies were present in the perivitelline space. The mitochondria were fully developed, distributed evenly and usually in close proximity with dilated endoplasmic reticula. Cortical granules were distributed at the periphery. At 40 h of incubation, a number of mitochondria was hooded. In oocytes of 2 to 4 layers of cumulus cells at 0 h, the zona pellucida was penetrated by cumulus cell processes, and the mitochondria were not well developed. However, in 20-h incubated oocytes, fully developed mitochondria, many of which were hooded, could be observed. Clusters of membrane-bound electron-transparent bodies were also observed, while cortical granules were at the periphery. In cumulus-free oocytes, zonation within the zona pellucida was indistinct. Very few vesicles and lipid bodies were observed. At 20 h, mitochondria were sparsely distributed and were not well developed and lacked cristae. At 40 h, the zona pellucida was less compact, and the membrane-bound electron-transparent bodies were less numerous compared with those of the other groups. Endoplasmic reticula were not dilated, and cortical granules were few and had no definite pattern of distribution.
    Matched MeSH terms: Oocytes
  10. Darbandi S, Darbandi M, Agarwal A, Khorshid HRK, Sadeghi MR, Esteves SC, et al.
    Int J Reprod Biomed, 2020 Jun;18(6):425-438.
    PMID: 32754678 DOI: 10.18502/ijrm.v13i6.7284
    Background: The three-parent assisted reproductive technique may increase oocyte competence.

    Objective: In this case-control study, the suitability of germinal vesicle transfer (GVT), synchronous ooplasmic transfer (sOT), asynchronous ooplasmic transfer using cryopreserved MII oocyte (caOT), and asynchronous ooplasmic transfer using waste MII oocyte (waOT) for maturation of the human-aged non-surrounded nucleolus germinal vesicle-stage (NSN-GV) oocyte were investigated.

    Materials and Methods: NSN-GV oocytes were subjected to four methods: group A (GVT), B (sOT), C (caOT) D (waOT), and E (Control). The fusion rates, MI, MII, ICSI observations and cleavage at 2-cell, 4-cell, and 8-cell stages were compared in the groups.

    Results: In GVT, none of the oocytes fused. In sOT, all oocytes fused, 20 achieved the MI, 14 progressed to MII, 8 fertilized, 6 cleaved and 5, 4, and 3 achieved the 2-cells, 4-cells and 8-cells, respectively. In caOT, all oocytes fused and achieved the MI, 8 progressed to MII and fertilized, 6 cleaved and 6, 5, and 5 achieved the 2-cells, 4-cells, and 8-cells respectively. In waOT, all oocytes fused, 5 and 3 progressed to MI and MII, respectively, but only one fertilized, cleaved and reached a 4-cells stage. In group E, 6 and 2 oocytes progressed to MI and MII, respectively, and only one fertilized but arrested at the zygote stage. caOT had the highest survival rate when compared to sOT (p = 0.04), waOT (p = 0.002), and control (p = 0.001).

    Conclusion: The caOT method was beneficial over sOT, waOT, and GVT in supplementing the developmental capacity of human-aged NSN-GV oocytes.

    Matched MeSH terms: Oocytes
  11. Teo A, Guest JR, Neo ML, Vicentuan K, Todd PA
    PeerJ, 2016;4:e2180.
    PMID: 27478697 DOI: 10.7717/peerj.2180
    Most studies of coral reproductive biology to date have focused on oocyte numbers and sizes. Only one (ex situ) study has enumerated sperm numbers, even though these data have multiple potential applications. We quantified total coral sperm and eggs per gamete bundle collected from six species in situ during a synchronous spawning event in Singapore. Egg-sperm bundles were captured midwater as they floated towards the surface after being released by the colony. For each sample, a semi-transparent soft plastic bottle was squeezed and released to create a small suction force that was used to 'catch' the bundles. This technique provided several advantages over traditional methods, including low cost, ease of use, no diving prior to the night of collection needed, and the ability to target specific areas of the colony. The six species sampled were Echinophyllia aspera, Favites abdita, F. chinensis, Merulina ampliata, M. scabricula and Platygyra pini. The mean number of sperm packaged within one egg-sperm bundle ranged from 2.04 × 10(6) to 1.93 × 10(7). The mean number of eggs per egg-sperm bundle ranged from 26.67 (SE ± 3.27) to 85.33 (SE ± 17.79). These data are critical for fertilisation success models, but the collection technique described could also be applied to studies requiring in situ spawning data at the polyp level.
    Matched MeSH terms: Oocytes
  12. Antony P, Rahman M, Rajkumar M, Kamaruzzaman Yunus, Ajmal Khan S
    Sains Malaysiana, 2014;43:1305-1310.
    Morphometric analysis was carried out to find out changes in the growth pattern of male and female stomatopod, Harpiosquilla raphidea. Six morphometric relationships were examined on 105 males and 105 females, ranging in size from 103 to 207 mm and from 104 to 222 mm in total length, respectively. In both the sexes, the relative growth of carapace length, propodus length of raptorial claw and total weight in relation to total length was found positively allometric. Telson width in both the sexes and abdomen width in males showed slightly negative allometry, while the abdomen width of females showed slightly positive allometry, indicating some variation in the growth between sexes which could be attributed to the energy requirement for maturation in females. The propodus of females was also found to be bigger than that of males. It is quite interesting as males only have larger chela in other crustaceans. It has a functional significance in that it is of immense help at the time of intense feeding during maturation of oocytes which requires higher energy.
    Matched MeSH terms: Oocytes
  13. Chin AHB
    J Assist Reprod Genet, 2022 Jul;39(7):1497-1500.
    PMID: 35653043 DOI: 10.1007/s10815-022-02526-9
    With social egg freezing being permitted in Singapore, there is expected to be an accumulated surplus of unused frozen eggs (vitrified oocytes) available for donation in coming years. A comprehensive update of current healthcare regulations pertaining to frozen egg donation is needed to resolve various pertinent ethical issues. In particular, the issue of egg donor anonymity should be addressed, together with the lack of sharing of medical and family information about the donor to prospective recipient patients and donor-conceived offspring. Rigorous and comprehensive genetic testing of prospective egg donors must be mandated to protect the welfare of recipient patients. Older women above 35 years of age should be required to have at least one child, before being allowed to donate their unused frozen eggs, to prevent any future regret and psychological problems of remaining childless, while being unsure of whether they have an unknown genetic offspring out there. New regulations drafted to address these ethical issues must also prevent potential conflicts of interests. For example, fertility doctors soliciting and encouraging former patients to donate their unused frozen eggs face an obvious conflict of interest, because additional medical fees will be earned by performing the egg donation procedure on other patients. A centralized donor registry should be established by the Singapore government to oversee the distribution and allocation of donated unused frozen eggs to infertile IVF patients. Such a registry could also facilitate sharing of vital health information about the donor to recipient patients and donor-conceived offspring.
    Matched MeSH terms: Oocytes
  14. Sallam H, Boitrelle F, Palini S, Durairajanayagam D, Parmegiani L, Jindal S, et al.
    Panminerva Med, 2023 Jun;65(2):159-165.
    PMID: 37194245 DOI: 10.23736/S0031-0808.23.04869-3
    Intracytoplasmic sperm injection (ICSI) was initially introduced to overcome problems due of severe male factor infertility not being solved with conventional in-vitro fertilization (cIVF). However, recent years have witnessed an increasing use of ICSI by most assisted reproductive technique laboratories for non-male factor indications. Examples of the latter include previous fertilization failure after cIVF, few or poor-quality oocytes, immature oocytes, advanced maternal age, preimplantation genetics test (PGT), cryopreserved oocytes, and unexplained infertility. The replacement of cIVF with ICSI in several non-male factor infertility cases is probably because some reproductive specialists consider that ICSI is associated with better reproductive outcomes. Unfortunately, data on reproductive outcomes in favor of ICSI over cIVF are limited or absent. Therefore, the factors that can help define the use of one technique over the other should be identified. These should include the likelihood of fertilization failure, potential risks of the procedure, and its costs. In this review, we aim to highlight the current guidelines, advantages, and limitations of the use of cIVF/ICSI for infertility treatment. Additionally, we provide a comprehensive review of the use of ICSI in indications other than severe male factor infertility.
    Matched MeSH terms: Oocytes
  15. Zhang J, Mohamad H, Wong JH, Bilal M, Ismail AHB, Lloyd AJ, et al.
    Malays J Med Sci, 2017 Mar;24(2):94-99.
    PMID: 28894409 DOI: 10.21315/mjms2017.24.2.12
    The α1β2γ2 subtype of GABAA receptors is the most commonly found GABAA receptor subtype in the mammalian cortex and hippocampus. It is expressed heterologously in the Xenopus laevis oocyte as a α1β2γ2S/L subtype for application as an in vitro model for the screening of compounds that modulate receptor activities. In fact, 4-hydroxybenzaldehyde (4-HB) has been identified as one of the major components in Dendrocalamus asper bamboo shoots in our previous study, and the current study showed that at 101.7 μM, 4-HB significantly reduced the GABA-induced chloride current of GABAA receptors expressed on Xenopus oocytes, indicating a possible GABAergic antagonistic effect at high concentrations.
    Matched MeSH terms: Oocytes
  16. Sabetian S, Shamsir MS, Abu Naser M
    Syst Biol Reprod Med, 2014 Dec;60(6):329-37.
    PMID: 25222562 DOI: 10.3109/19396368.2014.955896
    Elucidation of the sperm-egg interaction at the molecular level is one of the unresolved problems in sexual reproduction, and understanding the molecular mechanism is crucial in solving problems in infertility and failed in vitro fertilization (IVF). Many molecular interactions in the form of protein-protein interactions (PPIs) mediate the sperm-egg membrane interaction. Due to the complexity of the problem such as difficulties in analyzing in vivo membrane PPIs, many efforts have failed to comprehensively elucidate the fusion mechanism and the molecular interactions that mediate sperm-egg membrane fusion. The main purpose of this study was to reveal possible protein interactions and associated molecular function during sperm-egg interaction using a protein interaction network approach. Different databases have been used to construct the human sperm-egg interaction network. The constructed network revealed new interactions. These included CD151 and CD9 in human oocyte that interact with CD49 in sperm, and CD49 and ITGA4 in sperm that interact with CD63 and CD81, respectively, in the oocyte. These results showed that the different integrins in sperm may be involved in human sperm-egg interaction. It was also suggested that sperm ADAM2 plays a role as a protein candidate involved in sperm-egg membrane interaction by interacting with CD9 in the oocyte. Interleukin-4 receptor activity, receptor signaling protein tyrosine kinase activity, and manganese ion transmembrane transport activity are the major molecular functions in sperm-egg interaction protein network. The disease association analysis indicated that sperm-egg interaction defects are also reflected in other disease networks such as cardiovascular, hematological, and breast cancer diseases. By analyzing the network, we identified the major molecular functions and disease association genes in sperm-egg interaction protein. Further experimental studies will be required to confirm the significance of these new computationally resolved interactions and the genetic links between sperm-egg interaction abnormalities and the associated disease.
    Matched MeSH terms: Oocytes/metabolism*
  17. Abdullah JM, Zhang J
    Mini Rev Med Chem, 2013 Apr 01;13(5):744-8.
    PMID: 23373649
    The γ-aminobutyric acid (GABA) A receptor is composed of a variety of subunits and combinations and shows a characteristic distribution in the CNS. To date, 20 subunits of the GABA A receptor have been cloned: α1-6, β1-4, γ1-3, δ, π, ε , Θ, and ρ1-3. Oocyte of Xenopus laevis is one of the most frequently used heterologous expression systems, which are used to design and analyze specific combinations of GABA A receptor subunits. In oocytes, a certain GABA A receptor function is studied only by comparing the amplitude of the response to GABA and other drugs by physiological and pharmacological methods. According to the studies on Xenopus laevis oocytes, the α1β2γ2S receptor combination is mostly used. The α1-containing receptors mediate sedative and anticonvulsant acts. The results of studies on oocytes show that PKA, NKCC1, P2X3 receptors, and GABA A receptor-associated protein, etc., are existing systems that show different reactivity to the GABA A receptors. The GABA A receptor subunits contain distinct binding sites for BZDs, neurosteroids, general anesthetics, etc., which are responsible for the numerous functions of the GABA A receptor. A variety of other drugs, such as topiramate, TG41, (+)- and (-)-borneol, apigenin, and 6-methylflavone could also have modulatory effects on the GABA A receptors. Some of the different models and hypotheses on GABA A receptor structure and function have been achieved by using the two-electrode voltage clamp method in oocytes.
    Matched MeSH terms: Oocytes/metabolism
  18. Dorny P, Claerebout E, Vercruysse J, Sani R, Jalila A
    Vet Parasitol, 1994 Dec;55(4):327-42.
    PMID: 7725626
    Ninety-six randomly selected farms, located throughout peninsular Malaysia, were surveyed for goat nematodes resistant to benzimidazoles (BZ). On 33 farms BZ resistance was demonstrated by means of an egg hatch assay. Haemonchus contortus was found to be the main species involved in anthelmintic resistance. There was a positive association between the frequency of anthelmintic treatments on a farm and the presence of benzimidazole resistance. To assess the value of the egg hatch assay, faecal egg count reduction (FECR) tests were also performed on 20 farms. On six farms the LD50 of thiabendazole (TBZ) was less than 0.10 micrograms ml-1 and the FECR higher than 95% and on ten farms with an LD50 TBZ of over 0.10 micrograms ml-1 a FECR of less than 95% was measured. On four farms the FECR was less than 95%, although the egg hatch assay showed LD50 TBZ values of less than 0.10 micrograms ml-1 and on two of these three farms a controlled efficacy test confirmed the presence of BZ resistant H. contortus. From these results it can be concluded that the egg hatch assay underestimated the true incidence of benzimidazole resistance. Levamisole resistance was detected with a FECR test on two of ten farms investigated.
    Matched MeSH terms: Oocytes/drug effects
  19. Takahashi Y, Nihayah M, Jainudeen MR, Hishinuma M, Kanai Y, Mori Y, et al.
    J Vet Med Sci, 1992 Aug;54(4):799-801.
    PMID: 1391198
    Matched MeSH terms: Oocytes/physiology*
  20. Noorashikin M, Ong FB, Omar MH, Zainul-Rashid MR, Murad AZ, Shamsir A, et al.
    J Assist Reprod Genet, 2008 Jul;25(7):297-303.
    PMID: 18654847 DOI: 10.1007/s10815-008-9239-9
    Low dose stimulation (LS) is emerging as an alternative regime in assisted reproductive technology (ART). This study aimed to compare the cost-effectiveness of LS to the high dose GnRH antagonist (Atg) regime.
    Matched MeSH terms: Oocytes/metabolism
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