Displaying publications 41 - 60 of 656 in total

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  1. Descriptions of the female, male and mature larva of Simulium contractum Takaoka (Diptera: Simuliidae) from Sulawesi, Indonesia
    Takaoka H, Sofian-Azirun M, Chen CD, Halim MRA, Lau KW, Low VL, et al.
    Trop Biomed, 2020 Sep 01;37(3):683-690.
    PMID: 33612782 DOI: 10.47665/tb.37.3.683
    Simulium (Simulium) contractum Takaoka from Sulawesi, Indonesia was known only as the pupa. Its female, male and mature larva are described for the first time. The tentative assignment of this species in the Simulium dumogaense species-group is confirmed by the adult characters including the female and male genitalia. The female and male of this species are similar to those of Simulium (Simulium) tumpaense Takaoka and Roberts but are distinguished by the yellowish femora.
    Matched MeSH terms: Larva
  2. 5'-flanking sequences of zebrafish fast myosin heavy chain genes regulate unique expression in the anterior, medial subsection and posterior tail somites of the skeletal muscle
    Asaduzzaman M, Shakur Ahammad AK, Asakawa S, Kinoshita S, Watabe S
    Comp Biochem Physiol B Biochem Mol Biol, 2016 Jan;191:1-12.
    PMID: 26335505 DOI: 10.1016/j.cbpb.2015.08.009
    In zebrafish, fast muscle-specific myosin heavy chain genes have their unique expression patterns in a well-defined and restricted region of the skeletal muscle. However, the transcriptional regulatory mechanisms involved have remained unclear. Here, we examined the regulation of spatio-temporal expression patterns of myhz1 (myhz1.1, myhz1.2 and myhz1.3) and myhz2 during their development by using transient gene and stable transgenic techniques. Embryos microinjected with different length 5'-flanking sequences of myhz1 conjugated with the enhanced green fluorescent protein (EGFP) gene showed EGFP expression in the anterior and medial subsections of somites, but not in the tail somite region. In contrast, embryos microinjected with different length 5'-flanking sequences of myhz2 showed EGFP expression exclusively at the posterior tail somite domain. Promoter deletion analyses demonstrated that reduced EGFP fluorescence typically is correlated with smaller 5'-flanking sequences. The immunohistochemical observation revealed that zebrafish larvae provided with the transient gene and those from stable transgenic lines consistently expressed EGFP in the fast muscle fibers. r-VISTA plot identified one common conserved region of about 140°bp among myhz1.1, myhz1.2 and myhz1.3. Deletion of this conserved region from the 5'-flanking sequence of each myhz1 markedly reduced EGFP expression in its unique spatial somite region. Deletion mutation analysis demonstrated that myhz2 expression in the tail somite region might be mediated by Tbx (family of transcription factors having a common DNA-binding sequence known as T-box) binding elements. In summary, 5'-flanking sequences of myhz1 and myhz2 regulate their unique expression patterns in a well-defined and restricted somite region of the skeletal muscle in zebrafish.
    Matched MeSH terms: Larva
  3. Functional analysis of Trichinella spiralis serine protease 1.2 by siRNA mediated RNA interference
    Yang F, Guo KX, Yang DQ, Liu RD, Long SR, Zhang X, et al.
    Trop Biomed, 2020 Jun 01;37(2):458-470.
    PMID: 33612815
    A T. spiralis serine protease 1.2 (TsSP1.2) was identified in the muscle larvae (ML) and intestinal larvae surface/excretory-secretory (ES) proteins by immunoproteomics. The aim of this study was to determine the TsSP1.2 function in the process of T. spiralis intrusion, growth and reproduction by using RNA interference (RNAi). RNAi was used to silence the expression of TsSP1.2 mRNA and protein in the nematode. On 2 days after the ML were electroporated with 2 µM of TsSP1.2-specific siRNA 534, TsSP1.2 mRNA and protein expression declined in 56.44 and 84.48%, respectively, compared with untreated ML. Although TsSP1.2 silencing did not impair worm viability, larval intrusion of intestinal epithelium cells (IEC) was suppressed by 57.18% (P < 0.01) and the suppression was siRNA-dose dependent (r = 0.976). Infection of mice with siRNA 534 transfected ML produced a 57.16% reduction of enteral adult burden and 71.46% reduction of muscle larva burden (P < 0.05). Moreover, silencing of TsSP1.2 gene in ML resulted in worm development impediment and reduction of female fertility. The results showed that silencing of TsSP1.2 by RNAi inhibited larval intrusion and development, and reduced female fecundity. TsSP1.2 plays a crucial role for worm invasion and development in T. spiralis life cycle, and is a potential vaccine/drug target against Trichinella infection.
    Matched MeSH terms: Larva
  4. Trichinella spiralis: RNAi-mediated silencing of serine protease results in reduction of intrusion, development and fecundity
    Yang DQ, Zeng Y, Sun XY, Yue X, Hu CX, Jiang P, et al.
    Trop Biomed, 2020 Dec 01;37(4):932-946.
    PMID: 33612747 DOI: 10.47665/tb.37.4.932
    In previous studies, a Trichinella spiralis serine protease (TsSP) was identified in excretion/secretion (ES) products from intestinal infective L1 larvae (IIL1) using immunoproteomics. The complete cDNA sequence of TsSP gene was 1372 bp, which encoded 429 amino acids with 47.55 kDa. The TsSP was transcribed and expressed at all T. spiralis life cycle phases, as well as mainly located at the cuticle and stichosome of the parasitic nematode. Recombinant TsSP bind to intestinal epithelial cells (IEC) and promoted larva invasion, however, its exact function in invasion, development and reproduction are still unknown. The aim of this study was to confirm the biological function of TsSP during T. spiralis invasion and growth using RNA interference (RNAi) technology. The results showed that on 1 day after electroporation using 2.5 µM siRNA156, TsSP mRNA and protein expression of muscle larvae (ML) was suppressed by 48.35 and 59.98%, respectively. Meanwhile, silencing of TsSP gene by RNAi resulted in a 61.38% decrease of serine protease activity of ML ES proteins, and a significant reduction of the in vitro and in vivo invasive capacity of IIL1 to intrude into the IEC monolayer and intestinal mucosa. When mice were infected with siRNA 156-transfected larvae, adult worm and muscle larva burdens were decreased by 58.85 and 60.48%, respectively. Moreover, intestinal worm growth and female fecundity were evidently inhibited after TsSP gene was knockdown, it was demonstrated that intestinal adults became smaller and the in vitro newborn larval yield of females obviously declined compared with the control siRNA group. The results indicated that knockdown of TsSP gene by RNAi significantly reduced the TsSP expression and enzymatic activity, impaired larvae intrusion and growth, and lowered the female reproductive capacity, further verified that TsSP might participate in diverse processes of T. spiralis life cycle, it will be a new prospective candidate molecular target of anti-Trichinella vaccines.
    Matched MeSH terms: Larva
  5. Fulltext Spatial, environmental and entomological risk factors analysis on a rural dengue outbreak in Lundu District in Sarawak, Malaysia
    Cheah WL, Chang MS, Wang YC
    Trop Biomed, 2006 Jun;23(1):85-96.
    PMID: 17041556 MyJurnal
    The objective of this study was to elucidate the association of various risk factors with dengue cases reported in Lundu district, Sarawak, by analyzing the interaction between environmental, entomological, socio-demographic factors. Besides conventional entomological, serological and house surveys, this study also used GIS technology to generate geographic and environmental data on Aedes albopictus and dengue transmission. Seven villages were chosen based on the high number of dengue cases reported. A total of 551 households were surveyed. An overall description of the socio-demographic background and basic facilities was presented together with entomological and geographical profiles. For serological and ovitrap studies, systematic random sampling was used. Serological tests indicated that 23.7% of the 215 samples had a history of dengue, either recent or previous infections. Two samples (0.9%) were confirmed by IgM ELISA and 49 samples (22.8%) had IgG responses. A total of 32,838 Aedes albopictus eggs were collected in 56 days of trapping. Cluster sampling was also done to determine whether any of the risk factors (entomological or geographical) were influenced by geographical location. These clusters were defined as border villages with East Kalimantan and roadside villages along Lundu/Biawas trunk road. The data collected were analyzed using SPSS version 10.01. Descriptive analysis using frequency, means, and median were used. To determine the association between variables and dengue cases reported, and to describe the differences between the two clusters of villages, two-sample t-test, and Pearson's Chi-Square were used. Accurate maps were produced with overlay and density function, which facilitates the map visualization and report generating phases. This study also highlights the use of differential Global Positioning System in mapping sites of 1m accuracy. Analysis of the data revealed there are significant differences in clusters of villages attributable to container density, house density, distance of the house from the main road, and number of Ae. albopictus eggs from ovitraps set indoor, outdoor and in dumping sites (Person's Chi-Square = 6.111, df = 1, p < 0.01). Further analysis using t-test showed that house density, container density, indoor mosquitoes egg count, outdoor mosquitoes egg count, and dumping sites mosquitoes egg count were higher at the roadside villages compared to border villages. A number of potential risk factors including those generated from GIS were investigated. None of the factors investigated in this study were associated with the dengue cases reported.
    Matched MeSH terms: Larva
  6. Thermal death kinetics of Mediterranean, Malaysian, melon, and oriental fruit fly (Diptera: Tephritidae) eggs and third instars
    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: Larva/physiology
  7. Fulltext Adaptation and potential culture of wild Amphipods and Mysids as potential live feed in aquaculture: a review
    Suhaimi H, Abdul Rahman MI, Ashaari A, Ikhwanuddin M, Wan Rasdi N
    PeerJ, 2024;12:e17092.
    PMID: 38563012 DOI: 10.7717/peerj.17092
    Live foods such as phytoplankton and zooplankton are essential food sources in aquaculture. Due to their small size, they are suitable for newly hatched larvae. Artemia and rotifer are commonly used live feeds in aquaculture; each feed has a limited dietary value, which is unsuitable for all cultured species. Whereas, copepod and cladocerans species exhibit favorable characteristics that make them viable candidates as sources of essential nutrients for hatchery operations. Due to their jerking movements, it stimulates the feeding response of fish larvae, and their various sizes make them suitable for any fish and crustacean. Even though Artemia is the best live feed due to its proficient nutritional quality, the cost is very expensive, which is about half of the production cost. A recent study suggests the use of amphipods and mysids as alternative live feeds in aquaculture. High nutritional value is present in amphipods and mysids, especially proteins, lipids, and essential fatty acids that are required by fish larvae during early development. Amphipods and mysids are considered abundant in the aquatic ecosystem and have been used by researchers in water toxicity studies. However, the culture of amphipods and mysids has been poorly studied. There is only a small-scale culture under laboratory conditions for scientific research that has been performed. Thus, further research is required to find a way to improve the mass culture of amphipods and mysids that can benefit the aquaculture industry. This review article is intended to provide the available information on amphipods and mysids, including reproductive biology, culture method, nutritional value, feed enhancement, and the importance of them as potential live feed in aquaculture. This article is useful as a guideline for researchers, hatchery operators, and farmers.
    Matched MeSH terms: Larva
  8. Insecticide toxicity, glutathione transferases and carboxylesterase activities in the larva of the Aedes mosquito
    Shamaan NA, Hamidah R, Jeffries J, Hashim AJ, Wan Ngah WZ
    Comp Biochem Physiol C Comp Pharmacol Toxicol, 1993 Jan;104(1):107-10.
    PMID: 8097444
    1. Toxicity evaluations of DDT, lindane, abate and carbaryl were carried out in the larvae of two wild Aedes aegypti strains from Kuala Lumpur and Klang. The Kuala Lumpur strain was more susceptible to the insecticides than the Klang strain. 2. The lethal toxicity time was also determined. The insecticides were found to take a longer time to exert their effect in the Klang strain as compared to the Kuala Lumpur strain. 3. Carboxylesterase activity was determined to be higher in the Kuala Lumpur strain, but glutathione transferase activities were higher in the Klang strain.
    Matched MeSH terms: Larva/enzymology
  9. The control of the free-living stages of Strongyloides papillosus by the nematophagous fungus, Arthrobotrys oligospora
    Chandrawathani P, Omar J, Waller PJ
    Vet Parasitol, 1998 Apr 30;76(4):321-5.
    PMID: 9650868
    Two laboratory trials were conducted to determine the effect of the addition of spores (conidia) of the nematophagous fungus, Arthrobotrys oligospora, on the development of the ruminant parasite, Strongyloides papillosus, in cultures of bovine faeces. Both studies showed that at a concentration of 2000 conidia/g faeces virtually eliminated infective larvae (> 99% reduction), following 14 days incubation under ideal conditions (25 degrees C and saturated humidity) for free-living development of this parasite species. In one trial, a high level of control was also observed at a 10-fold decrease in conidia concentration (200 spores/g faeces). This work has demonstrated, in principle, that A. oligospora could provide a practical biological control agent against S. papillosus infecting intensively raised young ruminants in the humid tropics/subtropics.
    Matched MeSH terms: Larva
  10. Cessation of oiling in a malarious area during a certain season of the year [duplicate2]
    Wallace RB
    Malayan Medical Journal, 1932;7:73-81.
    Matched MeSH terms: Larva
  11. Histopathology of Brugia pahangi and Plasmodium berghei ANKA co-infection in the Gerbil (Meriones unguiculatus)
    Junaid OQ, Wong KT, Khaw LT, Mahmud R, Vythilingam I
    Trop Biomed, 2018 Dec 01;35(4):981-998.
    PMID: 33601846
    Co-infection with multiple different parasites is a common phenomenon in both human and animals. Among parasites that frequently co-infect the same hosts, are the filarial worms and malaria parasites. Despite this, the mechanisms underlying the interactions between these parasites is still relatively unexplored with very few studies available on the resulting pathologies due to co-infection by filarial nematodes and malaria parasites. Hence, this study investigated the histopathological effect of Brugia pahangi and Plasmodium berghei ANKA (PbA) infections in gerbil host. Gerbils grouped into B. pahangi-infected, PbA-infected, B. pahangi and PbA-coinfected, and uninfected control, were necropsied at different time points of post PbA infections. Brugia pahangi infections in the gerbils were first initiated by subcutaneous inoculation of 50 infective larvae, while PbA infections were done by intraperitoneal injection of 106 parasitized red blood cells after 70 days patent period of B. pahangi. Organs such as the lungs, kidneys, spleen, heart and liver were harvested aseptically at the point of necropsy. There was significant hepatosplenomegaly observed in both PbA-infected only and coinfected gerbils. The spleen, liver and lungs were heavily pigmented. Both B. pahangi and PbA infections (mono and coinfections) resulted in pulmonary edema, while glomerulonephritis was associated with PbA infections. The presence of both parasites induced extramedullary hematopoiesis in the spleen and liver. These findings suggest that the pathologies associated with coinfected gerbils were synergistically induced by both B. pahangi and PbA infections.
    Matched MeSH terms: Larva
  12. Fulltext Assessment of temperature effects on early larval development survival of hatchery-reared tropical oyster, Crassostrea iredalei
    Teh, Chiew Peng, Tan, Aileen Shau Hwai, Vengatesen, Thiyagarajan
    Trop Life Sci Res, 2016;27(11):111-116.
    MyJurnal
    The influence of the cool and warm temperatures on early life development and
    survival of tropical oyster, Crassostrea iredalei was studied. D-hinged larvae (day 1 larvae)
    were reared to three different temperatures (20°C, 27°C, and 34°C) for nine days. Oyster
    larvae reared in temperature 27°C, acted as control (ambient temperature). The highest
    survival rate occurred when the larvae were reared in 20°C and 27°C. Larvae reared at
    34°C exhibited reduced survival but increase in the growth rate. The growth rate in larvae
    reared in high temperature (34°C) was significantly higher compared to larvae reared in
    20°C and 27°C (p
    Matched MeSH terms: Larva
  13. Fulltext No evidence for successful interspecific cross-mating of transgenic Aedes aegypti (L.) and wild type Aedes albopictus Skuse
    Lee HL, Aramu M, Nazni WA, Selvi S, Vasan S
    Trop Biomed, 2009 Dec;26(3):312-9.
    PMID: 20237445
    The natural and artificial mating of laboratory bred Aedes albopictus and transgenic Aedes aegypti RIDL-513A-Malaysian strain was conducted. The experiment consisted of crossmating of homologous Ae. aegypti RIDL female symbol X Ae. aegypti RIDL male symbol and reciprocal Ae. aegypti RIDL female symbol X Ae. albopictus WT male symbol. The other set comprised homologous Ae. albopictus WT female symbol X Ae. albopictus WT male symbol and reciprocal Ae. albopictus WT female symbol X Ae. aegypti RIDL male symbol. This study demonstrated that reproductive barriers exist between these two species. Cross insemination occurred between A. albopictus male and Ae. aegypti female and their reciprocals. There was 26.67% and 33.33% insemination rate in Ae. aegypti RIDL female cross-mating with A. albopictus WT male and Ae. albopictus female cross-mating with Ae. aegypti RIDL male, respectively. There was 0% hatchability in both directions of the reciprocals. There was also no embryonation of these eggs which were bleached. Although none of the female Ae. albopictus WT was inseminated in the cross-mating with Ae. albopictus WT female symbol X Ae. aegypti RIDL male symbol, a total of 573 eggs were obtained. The homologous mating was very productive resulting in both high insemination rate and hatchability rates. Generally there was a significantly higher insemination rate with artificial mating insemination of homologous than with artificial mating of reciprocal crosses. Interspecific mating between Ae. aegypti RIDL and Ae. albopictus wild type was not productive and no hybrid was obtained, indicating absence of horizontal transfer of introduced RIDL gene in Ae. aegypti to Ae. albopictus.
    Matched MeSH terms: Larva
  14. Studies on the life cycle and developmental morphology of Cyclodontostomum purvisi (Adams, 1933) a hookworm parasite of Malayan giant rats
    Varughese G
    Southeast Asian J. Trop. Med. Public Health, 1973 Mar;4(1):78-95.
    PMID: 4718132
    Matched MeSH terms: Larva
  15. Preparation and Characterization of Alginate Microparticles Containing a Model Protein for Oral Administration in Gnotobiotic European Sea Bass (Dicentrarchus labrax) Larvae
    Yaacob EN, Goethals J, Bajek A, Dierckens K, Bossier P, De Geest BG, et al.
    Mar Biotechnol (NY), 2017 Aug;19(4):391-400.
    PMID: 28643227 DOI: 10.1007/s10126-017-9758-4
    Aquaculture is the fastest growing animal production sector. However, the production of marine fish is still hampered by the high mortality rate in the first few weeks after hatching. Mortality in larvae is often caused by microbial infections. Today, the incorporation of immunostimulants into microparticles provides us new tools to enhance disease resistance in marine larviculture. In this study, we prepared alginate microparticles loaded with the model antigen fluorescein isothiocyanate conjugated-bovine serum albumin. Optimum concentrations of alginate and CaCl2, the correct alginate viscosity and the appropriate preparatory conditions led to the creation of desirable microparticles with the correct size for oral feeding in gnotobiotic European sea bass larvae. The prepared alginate microparticles were stable in sea water and were successfully ingested by gnotobiotic sea bass larvae at day after hatching 7 without causing any negative effects. Results suggest the suitability of this drug delivery system for targeting the innate immune system of fish larvae in order to enhance disease resistance and thus reduce mortality in larviculture.
    Matched MeSH terms: Larva
  16. Recombinant ferritin-H induces immunosuppression in European sea bass larvae (Dicentrarchus labrax) rather than immunostimulation and protection against a Vibrio anguillarum infection
    Yaacob EN, De Geest BG, Goethals J, Bajek A, Dierckens K, Bossier P, et al.
    Vet Immunol Immunopathol, 2018 Oct;204:19-27.
    PMID: 30596377 DOI: 10.1016/j.vetimm.2018.09.001
    Vibrio anguillarum causes high mortality in European sea bass (Dicentrarchus labrax) larviculture. In this study, we evaluated if the recombinant sea bass ferritin-H could stimulate the innate immune system of gnotobiotic European sea bass larvae resulting in protection against a V. anguillarum challenge. We also evaluated the effect of a V. anguillarum infection on the transcription of immune-related genes in gnotobiotic European sea bass larvae. Recombinant sea bass ferritin-H was produced, encapsulated in calcium alginate microparticles and orally delivered to sea bass larvae at seven days after hatching. Our results showed V. anguillarum caused an acute infection, resulting in high mortality. The infection significantly upregulated the expression of tlr3, tlr5, cas1, il1β, tnfα, mif, il10, cc1, cxcl8 at 18, 24 and 36 h post infection, but not of the chemokine receptor genes cxcr4 and ccr9. There was no protective effect of ferritin-H. Remarkably, ferritin-H caused significantly higher transcript levels for cxcr4 and ccr9. Sea bass ferritin-H was more likely involved in immune-suppression and results point in the direction of a negative regulation of CXCR4 resulting in inhibition of cell proliferation, differentiation and migration which is detrimental to innate immunity and might explain the non-protective effect of ferritin-H in fish larvae.
    Matched MeSH terms: Larva/microbiology
  17. Biogenic larvicidal formulation of metabolites from Steinernema saimkayi symbiont Xenorhabdus stockiae KUT6 against dengue vector Aedes aegypti
    Jissin M, Vani C
    Trop Biomed, 2020 Sep 01;37(3):791-802.
    PMID: 33612792 DOI: 10.47665/tb.37.3.791
    To characterize the production and larvicidal activity of Xenorhabdus stockiae KUT6 Petroleum ether extracts from Luria Broth and induced Quorum sensing medium containing N-3- oxododecanoyl Homoserine Lactone inducer against dengue vector Aedes aegypti. The Galleria mellonella larvae were reared for the isolation of Steinernema saimkayi symbiont Xenorhabdus stockiae KUT6 from Cucumber field soil sample in NBTA. Then for the extraction of compounds the KUT6 strains were cultured in Luria Broth and Quorum Sensing optimized media using N-3-oxododecanoyl homoserine lactone inducer. The larvicidal activity of Xenorhabdus stockiae KUT6 of petroleum ether extracts were bioassayed against 4th instar Aedes aegypti dengue vector. The maximum rate of mortality were recorded of the samples A-24h, B-48h, C-72h, A1-24h, B1-48h, C1-72h at different concentrations 50 µg/ml, 100 µg/ml and 150 µg/ml respectively for 24h to 72h of exposure treatment. The morphological characteristics of Xenorhabdus stockiae KUT6 in NBTA were red core colonies with blue background surrounded by zone of inhibition. After 24h exposure maximum rate of 100% mortality of Aedes aegypti 4th instar larvae was attained when treated with sample C1-72h 50 µg/ml of the petroleum ether extracts of quorum sensed medium whereas the sample C 72h petroleum ether extracts of KUT6 cultured in Luria broth recorded 100% mortality at 150 µg on 24h exposure indicates enhancement in the product yield. The study assures the use of Xenorhabdus stockiae KUT6 petroleum ether extracts as biocontrol agent could be beneficial for the control of dengue vectors.
    Matched MeSH terms: Larva
  18. Investigations for the Possible Use of a Monoclonal Antibody Produced against Strongyloides ratti Antigen as an Immunodiagnostic Reagent for Active Strongyloidiasis
    Mahmuda A, Bande F, Abdulhaleem N, Abd Majid R, Awang Hamat R, Omar Abdullah W, et al.
    Iran J Parasitol, 2018 8 3;13(2):204-214.
    PMID: 30069204
    Background: Currently, most of the available serological diagnostic kits for strongyloidiasis are based on the use of the crude antigens of Strongyloides ratti, which are good, but with less sensitivity towards the infection. Hence, this study aimed to produce and evaluate monoclonal antibody for detecting soluble parasite antigen in animal sera.

    Methods: The study was conducted in the Department of Medical Microbiology and Parasitology, University Putra Malaysia in 2014-2017. Saline extract protein from the infective larvae of S. ratti was used to immunize BALB/c mice and subsequent fusion of the B-cells with myeloma cells (SP2/0) using 50% PEG. The hybridomas were cultured in HAT medium and cloned by limiting dilutions. Positive hybrids were screened by indirect ELISA. The ascites fluid from the antibody-secreting hybridoma was purified and the MAb was characterized by western-blots and evaluated in sandwich ELISA for reactivity against the homologous and heterologous antigens.

    Results: An IgG1 that recognizes a 30 and 34 kDa protein bands was obtained. The MAb was recognized by all S. ratti-related antigens and cross-reacted with only Toxocara canis antigens in both assays. The minimum antigen detection limit was found to be 5 ng/ml. All antibody-positive rat and dog sera evaluated have shown antigen-positive reactions in Sandwich-ELISA.

    Conclusion: The MAb produced, was able to detect antigens in strongyloidiasis and toxocariasis in animal models and may also be useful for the serological detection of active strongyloidiasis and visceral toxocariasis in human sera.

    Matched MeSH terms: Larva
  19. Fulltext Effects of delayed metamorphosis on larval survival, metamorphosis, and juvenile performance of four closely related species of tropical sea urchins (genus Echinometra)
    Rahman MA, Yusoff FM, Arshad A, Uehara T
    ScientificWorldJournal, 2014;2014:918028.
    PMID: 24624048 DOI: 10.1155/2014/918028
    We report here, the effects of extended competency on larval survival, metamorphosis, and postlarval juvenile growth of four closely related species of tropical sea urchins, Echinometra sp. A (Ea), E. mathaei (Em), Echinometra sp. C (Ec), and E. oblonga (Eo). Planktotrophic larvae of all four species fed on cultured phytoplankton (Chaetoceros gracilis) attained metamorphic competence within 22-24 days after fertilization. Competent larvae were forced to delay metamorphosis for up to 5 months by preventing them from settling in culture bottles with continuous stirring on a set of 10 rpm rotating rollers and larval survival per monthly intervals was recorded. Larval survival was highest at 24 days, when competence was attained (0 delayed period), and there were no significant differences among the four species. Larvae that had experienced a prolonged delay had reduced survival rate, metamorphosis success, and juvenile survival, but among older larvae, Em had the highest success followed by Ea, Eo, and Ec. Juveniles from larvae of all four species that metamorphosed soon after becoming competent tended to have higher growth rates (test diameter and length of spines) than juveniles from larvae that metamorphosed after a prolonged period of competence with progressively slower growth the longer the prolonged period. Despite the adverse effects of delaying metamorphosis on growth parameters, competent larvae of all four species were able to survive up to 5 months and after metamorphosis grew into 1-month-old juveniles in lab condition. Overall, delayed larvae of Em showed significantly higher larval survival, metamorphosis, and juvenile survival than Ea and Eo, while Ec showed the lowest values in these performances. Em has the most widespread distribution of these species ranging from Africa to Hawaii, while Ec probably has the most restricted distribution. Consequently, differences in distribution may be related to differences in the ability to delay metamorphosis.
    Matched MeSH terms: Larva/growth & development
  20. Fulltext Severe Orbital Myiasis Caused by Chrysomya bezziana: A Case Report
    Ng YS, Gan YK, Tupang L
    Turk J Ophthalmol, 2021 Feb 25;51(1):62-65.
    PMID: 33631919 DOI: 10.4274/tjo.galenos.2020.00225
    An 88-year-old woman was brought to the hospital immediately after her neighbours noticed that she was bleeding from her right eye. On examination, her right eye was phthisic with maggot infestation of her right orbit. Over a hundred live maggots were extracted using forceps. Computed tomography scan revealed the infestation was confined to the right orbit. The patient underwent exenteration of the right orbit under general anaesthesia. The species was identified by an entomologist as Chrysomya bezziana, which has aggressive larvae that eat living tissue. This case report demonstrates that orbital myiasis caused by C. bezziana poses a very real risk of intracranial invasion as they feed on living tissues. Adjacent tissue destruction can be very rapid and definitive treatment involves urgent removal of its larvae via surgical debridement. To our knowledge, we are reporting the first case of orbital myiasis from a patient in Malaysia. Therefore, our case report may be helpful in the management of similar case of orbital myiasis.
    Matched MeSH terms: Larva
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