Displaying publications 1 - 20 of 74 in total

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  1. AlDahoul N, Karim HA, Momo MA, Escobar FIF, Magallanes VA, Tan MJT
    Sci Rep, 2023 Sep 02;13(1):14475.
    PMID: 37660120 DOI: 10.1038/s41598-023-41711-3
    Intestinal parasitic infections (IPIs) caused by protozoan and helminth parasites are among the most common infections in humans in low-and-middle-income countries. IPIs affect not only the health status of a country, but also the economic sector. Over the last decade, pattern recognition and image processing techniques have been developed to automatically identify parasitic eggs in microscopic images. Existing identification techniques are still suffering from diagnosis errors and low sensitivity. Therefore, more accurate and faster solution is still required to recognize parasitic eggs and classify them into several categories. A novel Chula-ParasiteEgg dataset including 11,000 microscopic images proposed in ICIP2022 was utilized to train various methods such as convolutional neural network (CNN) based models and convolution and attention (CoAtNet) based models. The experiments conducted show high recognition performance of the proposed CoAtNet that was tuned with microscopic images of parasitic eggs. The CoAtNet produced an average accuracy of 93%, and an average F1 score of 93%. The finding opens door to integrate the proposed solution in automated parasitological diagnosis.
    Matched MeSH terms: Ovum/classification; Ovum/cytology
  2. Hanson SM, Craig GB
    J Med Entomol, 1995 Sep;32(5):599-604.
    PMID: 7473614
    Aedes albopictus (Skuse) is an Asian mosquito that recently has colonized North America via used tire transport. Temperate Ae. albopictus populations overwinter as diapausing eggs, but tropical populations cannot diapause. Eggs of tropical (SABAH) and temperate (INDY) Ae. albopictus were obtained in diapause-inducing conditions and placed inside a scrap tire to monitor overwintering survival in northern Indiana during the winters of 1989-1990 and 1990-1991. Diapause eggs of Ae. triseriatus (Say), a native North American mosquito, were included for comparison. Tropical Ae. albopictus from Malaysia did not survive either winter. Temperate Ae. albopictus from Indianapolis, IN, did not survive the winter of 1989-1990, but 78% survived the winter of 1990-1991. In contrast, 92 and 96% of Ae. triseriatus survived the winters of 1989-1990 and 1990-1991, respectively. Neither mean temperature nor absolute minimum temperature (a winter's lowest temperature) accurately predicted Ae. albopictus overwintering survivorship in the field. The possible effect of snow and other insulating materials on the overwintering survivorship of Ae. albopictus eggs is discussed.
    Matched MeSH terms: Ovum*
  3. 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: Ovum/metabolism*; Ovum/physiology*
  4. Eng KL, Chiang GL, Hamidah T, Loong KP
    PMID: 1976273
    Descriptions of the eggs of Mansonia uniformis, Ma. indiana and Ma. annulifera are provided with the aid of scanning electron micrographs. Eggs of these three species, although similar in shape and colour, are covered by outer chorionic reticulum and tubercles which provide reliable morphological character for their identification. Size, distribution and number of lobes on the large tubercles present in the region between the anterior tube and posterior region, are important distinguishing features. Measurements of egg sizes and other chorionic differences are also discussed.
    Matched MeSH terms: Ovum/ultrastructure*
  5. Lah EF, Musa RN, Ho TM
    Asian Pac J Trop Biomed, 2012 Sep;2(9):679-83.
    PMID: 23569994 DOI: 10.1016/S2221-1691(12)60209-3
    To examined the immediate and 24 hours post- irradiation germicidal effects of UV-C lamp on eggs and adults of house dust mites Dermatophagoides pteronyssinus (D. pteronyssinus) and Dermatophagoides farinae (D. farinae).
    Matched MeSH terms: Ovum/cytology; Ovum/pathology; Ovum/radiation effects*
  6. Cheong WH
    Med J Malaya, 1968 Mar;22(3):242.
    PMID: 4234377
    Matched MeSH terms: Ovum
  7. Tun S, Ithoi I, Mahmud R, Samsudin NI, Kek Heng C, Ling LY
    PLoS One, 2015;10(12):e0142231.
    PMID: 26671680 DOI: 10.1371/journal.pone.0142231
    The present study was conducted to determine the prevalence of helminth eggs excreted in the faeces of stray cats, dogs and in soil samples. A total of 505 fresh samples of faeces (from 227 dogs and 152 cats) and soil were collected. The egg stage was detected via microscopy after the application of formalin-ether concentration technique. Genomic DNA was extracted from the samples containing hookworm eggs and used for further identification to the species level using real-time polymerase chain reaction coupled with high resolution melting analysis. Microscopic observation showed that the overall prevalence of helminth eggs among stray cats and dogs was 75.7% (95% CI = 71.2%-79.9%), in which 87.7% of dogs and 57.9% of cats were infected with at least one parasite genus. Five genera of heliminth eggs were detected in the faecal samples, including hookworms (46.4%), Toxocara (11.1%), Trichuris (8.4%), Spirometra (7.4%) and Ascaris (2.4%). The prevalence of helminth infections among stray dogs was significantly higher than that among stray cats (p < 0.001). Only three genera of helminths were detected in soil samples with the prevalence of 23% (95% CI = 15.1%-31%), consisting of hookworms (16.6%), Ascaris (4%) and Toxocara (2.4%). The molecular identification of hookworm species revealed that Ancylostoma ceylanicum was dominant in both faecal and soil samples. The dog hookworm, Ancylostoma caninum, was also detected among cats, which is the first such occurrence reported in Malaysia till date. This finding indicated that there was a cross-infection of A. caninum between stray cats and dogs because of their coexistent within human communities. Taken together, these data suggest the potential role of stray cats and dogs as being the main sources of environmental contamination as well as for human infections.
    Matched MeSH terms: Ovum/cytology*
  8. Jais AM, Matori MF, Kittakoop P, Sowanborirux K
    Gen. Pharmacol., 1998 Apr;30(4):561-3.
    PMID: 9522175
    1. Fatty acid profiles in the external mucus extract and roe of Channa striatus were determined using gas chromatography (GC). 2. The mucus samples were collected by inducing hypothermic stress (-20 degrees C) for about 1 hr, and the roe were collected from gravid females at night soon after they liberated their eggs in a spawning program. 3. All mucus and roe samples were freeze-dried, except a part of roe which was not. 4. The mucus extract contained unsaturated fatty acid (oleic acid, C18:1 and linoleic acid, C18:2) as a major component, 21.25% and 22.47% of total lipid. 5. For the freeze- and nonfreeze-dried roe, the major components of fatty acid were somewhat similar to the mucus but with higher percentages: 58.56%, 26.08% and 45.76%, 20.94%. Interestingly, the nonfreeze-dried roe contained a large proportion of arachidic acid, C20:0 (22.16%), which was totally absent in the freeze-dried roe samples. 6. This profiling of the fatty acid mucus extract and roe is useful in strengthening the earlier claims that haruan possesses a potential remedy for wound healing (Mat Jais et al., 1994). Therefore, we are discussing the possibility of getting an optimum amount of the essential fatty acid for wound healing from various other parts of the fish without sacrificing the fish.
    Matched MeSH terms: Ovum/chemistry*
  9. Hawley WA, Reiter P, Copeland RS, Pumpuni CB, Craig GB
    Science, 1987 May 29;236(4805):1114-6.
    PMID: 3576225
    North American strains of Aedes albopictus, an Asian mosquito recently introduced into the Western Hemisphere, exhibit photoperiodic sensitivity and cold-hardiness characteristics similar to strains originating from temperate zone Asia. Trade statistics for used tire imports, the most likely mode of introduction, also indicate a north Asian origin. Aedes albopictus, an important vector of dengue and a potential vector of many other arboviral diseases, may therefore have the capability of infesting much of temperate North America.
    Matched MeSH terms: Ovum/physiology
  10. Canning EU, Sinden RE, Landau I, Miltgen F
    Ann Parasitol Hum Comp, 1976 11 1;51(6):607-23.
    PMID: 829210
    An immature merocyst of Hepatocystis malayensis and gametocytes of H. brayi were studied with the electron microscope. The merocyst consisted of a highly complex cytoplasmic reticulum ramifying through an amorphous matrix: the entire complex was enclosed by a simple unit membrane. The host cell was apparently destroyed completely during growth of the cyst. Immature gametocytes were highly amoeboid and showed extensive vacuolisation or attenuation of the cytoplasm. The nucleus contained one or two prominent nucleoli. Mature gametocytes had compact cytoplasm and contained pyriform osmiophilic bodies which were believed to function in the release of the parasites from the host cells. Macrogametocytes were distinguished from microgametocytes by cytoplasmic differences in numbers of ribosomes, and cristate mitochondria and in the extent of development of the smooth endoplasmic reticulum. The compact nuclei of the macrogametocytes had inconspicuous DNA but prominent nucleoli whereas those of the microgametocytes were irregular and showed a central aggregate of DNA. In microgametogenesis karyokinesis of the parent nucleus was delayed until axoneme formation was complete. Then the nuclear buds were extruded into emerging microgametes. At fertilisation the plasmalemmas of the two gametes fused and the single axoneme and nucleus of the microgamete moved into the cytoplasm of the macrogamete.
    Matched MeSH terms: Ovum/ultrastructure
  11. Saifur RG, Dieng H, Hassan AA, Satho T, Miake F, Boots M, et al.
    J Am Mosq Control Assoc, 2010 Dec;26(4):373-80.
    PMID: 21290932
    Moisture plays a major role in the dynamics of mosquito populations, especially those breeding in container habitats. Despite this importance, the role of moisture conditions as they affect oviposition and egg development in Aedes vectors remains largely unexplored. We investigated the effect of exposing gravid female Aedes albopictus mosquitoes and their eggs to different moisture levels (MLs) for various periods on oviposition and hatching. Overall, high-moisture substrates (HMSs; 66% and 72%) provided better environments for egg laying. The timing of initial egg laying was far longer at the lowest substrate moisture level (LSML, 25% and 41.2%) than at HMSs. The numbers of eggs laid were much lower in the drier environments. At LSMLs, gravid females retained increasing numbers of mature eggs until death, and egg retention decreased gradually with increasing ML. The HMSs also provided better environments for larval eclosion. The numbers of eggs hatched were lower at the LSML than the HSML environment. No egg hatching occurred after 1 h exposure to moisture. However, egg hatching occurred by installment, with spontaneous hatching (SH) increasing gradually with increasing ML. High-moisture conditions combined with long exposure (30 h and 48 h) favored SH. These results suggest that Ae. albopictus females can respond to better moisture conditions for increased success of embryonation and larval eclosion. This information may be useful in the colonization of floodwater Aedes species.
    Matched MeSH terms: Ovum/physiology
  12. 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: Ovum/physiology*
  13. Hook SA, Musa SM, Ripley DM, Hibbitt JD, Grunow B, Moritz T, et al.
    PLoS One, 2019;14(12):e0224397.
    PMID: 31790403 DOI: 10.1371/journal.pone.0224397
    Elasmobranchs display various reproductive modes, which have been key to their evolutionary success. In recent decades there has been a rise in the number of reported cases of foetal abnormalities including fertilised, double-embryos held within one egg capsule, hereafter referred to as twins. Previously, the occurrences of twin egg cases have been reported in two batoid and one shark species. We report the first cases of twins in three species of oviparous elasmobranchs: the undulate ray (Raja undulata), the nursehound (Scyliorhinus stellaris), and the small-spotted catshark (Scyliorhinus canicula). We investigated the genetic relationships between the twins in S. stellaris, and S. canicula using microsatellite markers. Whilst the S. stellaris twins displayed the same genotypes, we found that the S. canicula twin individuals arose through heteropaternal superfecundation. This is the first reported incidence of such a paternity in elasmobranchs. The relationship between environmental change and reproductive strategy in elasmobranchs is unclear and further research is needed to determine its effect on the prevalence and mechanisms of formation of elasmobranch twins.
    Matched MeSH terms: Ovum/physiology*
  14. Armstrong JW, Tang J, Wang S
    J Econ Entomol, 2009 Apr;102(2):522-32.
    PMID: 19449631
    The late-aged egg and third-instar life stages of laboratory-reared Malaysian fruit fly, Bactrocera latifrons (Hendel); Mediterranean fruit fly, Ceratitis capitata (Wiedemann); melon fly, B. cucurbitae Coquillett; and oriental fruit fly, B. dorsalis (Hendel), (Diptera: Tephritidae); and the third instars of wild Mediterranean fruit fly were exposed to thermal treatments. A heating block system was used to determine the thermal death kinetics of the four fruit fly species. Treatments consisted of heating the fruit fly life stages to 44, 46, 48, and 50 degrees C and holding for different times ranging from 0 to 120 min depending on the thermal mortality response and time required to obtain 100% mortality for each species and life stage. The 0.5-order kinetic model had the best fit to the survival ratio for all the treatment temperatures and was used to predict lethal times. The thermal death time (TDT) curves showed a tolerance order of Mediterranean fruit fly eggs < or = third instars at 44, 46, and 50 degrees C, third instars < or = eggs at 48 degrees C, and wild third instars < the laboratory-reared third instars. Comparison between Mediterranean fruit fly third instar thermotolerance from Hawaii and Israel showed that Israel Mediterranean fruit fly was more thermotolerant. A comparison of minimum treatment times at a given temperature required to obtain 100% mortality of laboratory-reared Malaysian, Mediterranean (Hawaii and Israel strains), melon, Mexican, and oriental fruit fly eggs or third instars and wild Mediterranean fruit fly (Hawaii strain) eggs or third instars showed that oriental fruit fly was the most thermotolerant among the third instars, and the difference in heat tolerance between third instars and eggs was negligible at 50 degrees C.
    Matched MeSH terms: Ovum/physiology*
  15. Rusli MU, Booth DT, Joseph J
    J Exp Biol, 2016 05 15;219(Pt 10):1505-13.
    PMID: 27207954 DOI: 10.1242/jeb.134742
    A potential advantage of group movement in animals is increased locomotion efficiency. This implies a reduced energetic cost for individuals that occur in larger groups such as herds, flocks and schools. When chelonian hatchlings hatch in the underground nest with finite energy for their post-hatching dispersal phase, they face the challenge of minimizing energetic expenditure while escaping the nest. The term 'social facilitation' has been used to describe the combined digging effort of sea turtle hatchlings during nest escape. Given that in a normal clutch, a substantial part of the energy reserve within the residual yolk is used by hatchlings in the digging out process, a decreased cohort size may reduce the energy reserve available to cross the beach and sustain the initial swimming frenzy. This hypothesis was experimentally tested by varying cohort size in hatchling green turtles (Chelonia mydas) and measuring energy expenditure during the nest escape process using open-flow respirometry. The energetic cost of escaping through 40 cm of sand was calculated to vary between 4.4 and 28.3 kJ per individual, the cost decreasing as the number of individuals in the cohort increased. This represents 11-68% of the energy contained in a hatchling's residual yolk at hatching. The reduced energetic cost associated with large cohorts resulted from both a lower metabolic rate per individual and a shortened nest escape time. We conclude that synchronous digging activity of many hatchlings during nest escape evolved not only to facilitate rapid nest emergence but also to reduce the energetic cost to individuals.
    Matched MeSH terms: Ovum/physiology
  16. Fukui M, Fujita M, Tomizuka S, Mashimo Y, Shimizu S, Lee CY, et al.
    Arthropod Struct Dev, 2018 Jan;47(1):64-73.
    PMID: 29109050 DOI: 10.1016/j.asd.2017.11.001
    The egg structure and outline of the embryonic development of Metallyticus splendidus of one of the basal Mantodea representatives, Metallyticidae, were described in the present study. The results obtained were compared with those from the previous studies, to reconstruct and discuss the groundplan of Mantodea and Dictyoptera. In M. splendidus, the egg is spheroidal, it has a convex ventral side at the center in which numerous micropyles are grouped, and it possesses a conspicuous hatching line in its anterior half. These are the groundplan features of mantodean eggs and the "grouped micropyles in the ventral side of the egg" are regarded as an apomorphic groundplan feature of Dictyoptera. A small circular embryo is formed by a simple concentration of blastoderm cells, which then undergoes embryogenesis of the typical short germ band type. Blastokinesis is of the "non-reversion type" and the embryo keeps its original superficial position and original orientation throughout embryonic development. During the middle stages of development, the embryo undergoes rotation around the egg's anteroposterior axis. These features are a part of the groundplan of Mantodea. It is uncertain whether sharing of the "non-reversion type" of blastokinesis by Mantodea and blaberoidean Blattodea can be regarded as homology or homoplasy.
    Matched MeSH terms: Ovum/ultrastructure
  17. Miyagi I, Toma T, Okazawa T, Mogi M, Hashim R
    J Am Mosq Control Assoc, 2005 Dec;21(4):466-8.
    PMID: 16506575
    During a mosquito survey in Ulu Gombak, Selangor, Peninsular Malaysia, October 2-16, 2003, we observed a peculiar oviposition habit of Armigeres flavus. This strange behavior is described and illustrated with photographs; although it is well known, no detailed description has been made previously.
    Matched MeSH terms: Ovum
  18. 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: Ovum
  19. Zuha RM, Omar B
    Parasitol Res, 2014 Jun;113(6):2285-94.
    PMID: 24728523 DOI: 10.1007/s00436-014-3883-z
    Cosmopolitan scuttle fly, Megaselia scalaris (Loew) (Diptera: Phoridae) is one of the commonest forensic species recorded colonizing human corpse indoors and in concealed environment. The occurrence of this species in such environments provides a higher evidential value to assist estimation of postmortem interval (PMI) compared to other forensically important dipterans. However, developmental and size data of M. scalaris are still lacking and they are derived from a limited range of thermal values. The objective of this study is to develop the growth model of M. scalaris by emphasizing the size range of larvae and puparia at different constant temperatures. This species was reared in six replicates at eight varying constant temperatures ranging from 23 to 36 °C and cow's liver was provided as food source. Larvae and puparia were sampled at set time intervals and measured by their length and weight. Because interpretation of forensic entomological evidence is subject to application of different techniques, development of M. scalaris is expressed herein by using developmental table, length/morphological stage diagrams and linear/nonlinear estimation methods. From the findings, it is very important to highlight that sexual dimorphism of M. scalaris during post feeding larva and pupa stage could be observed based on size and developmental periods. Mean length and weight ratios of male to female puparia are approximately 0.8 and 0.3-0.5, respectively, indicating sexual dimorphism of this species. Developmental period in female are 4.0-11.4 h (post feeding larval stage), 3.7-24.0 h (pupal stage), and 3.0-20.1 h (total developmental period) longer in male. Due to this dimorphism, PMI estimation using M. scalaris post feeding larva or puparium specimens must be carried out carefully by to avoid inaccuracy and misinterpretation.
    Matched MeSH terms: Ovum/growth & development; Ovum/physiology
  20. Abu Tahir N, Ahmad AH
    J Med Entomol, 2013 Sep;50(5):999-1002.
    PMID: 24180104
    Effects of laterite cover soil with different characteristics on survival of buried eggs, third instar larvae, and pupae of Musca domestica (L.) were studied experimentally. Soil treatments were loose dry soil, loose wet soil, compacted dry soil, and compacted wet soil (CWS). Eggs, third instar larvae, and pupae were buried under 30 cm of the different soil treatments and placed under field conditions until adults emerged. Rearing medium was provided for eggs and larvae, and control treatments of all stages were unburied immatures placed on soil surface. Egg and pupal survival to adult were significantly affected by the cover soil treatments, but third instars were more resilient. Wet soil treatments (loose wet soil and CWS) resulted in significantly reduced pupal survival, but increased survival of eggs. However, CWS significantly reduced adult emergence from buried eggs. Though emergence of house flies buried as eggs was significantly reduced, some were able to hatch and emerging first instar larvae developed to pupation. Although cover soil does not completely prevent fly emergence, it did limit development and emergence of buried house flies.
    Matched MeSH terms: Ovum/growth & development; Ovum/physiology
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