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Journal articles on the topic 'Hemichromis'

Author: Grafiati

Published: 4 June 2021

Last updated: 18 February 2022

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1

Jorissen, Michiel W. P., Antoine Pariselle, Tine Huyse, Emmanuel J. Vreven, Jos Snoeks, Eva Decru, Thomas Kusters, et al. "Six new dactylogyrid species (Platyhelminthes, Monogenea) from the gills of cichlids (Teleostei, Cichliformes) from the Lower Congo Basin." Parasite 25 (2018): 64. http://dx.doi.org/10.1051/parasite/2018059.

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The Lower Congo Basin is characterized by a mangrove-lined estuary at its mouth and, further upstream, by many hydrogeographical barriers such as rapids and narrow gorges. Five localities in the mangroves and four from (upstream) left bank tributaries or pools were sampled. On the gills of Coptodon tholloni, Coptodon rendalli, Hemichromis elongatus, Hemichromis stellifer and Tylochromis praecox, 17 species of parasites (Dactylogyridae & Gyrodactylidae, Monogenea) were found, eight of which are new to science. Six of these are herein described: Cichlidogyrus bixlerzavalai n. sp. and Cichlidogyrus omari n. sp. from T. praecox, Cichlidogyrus calycinus n. sp. and Cichlidogyrus polyenso n. sp. from H. elongatus, Cichlidogyrus kmentovae n. sp. from H. stellifer and Onchobdella ximenae n. sp. from both species of Hemichromis. On Cichlidogyrus reversati a ridge on the accessory piece was discovered that connects to the basal bulb of the penis. We report a putative spillback effect of the native parasites Cichlidogyrus berradae, Cichlidogyrus cubitus and Cichlidogyrus flexicolpos from C. tholloni to the introduced C. rendalli. From our results, we note that the parasite fauna of Lower Congo has a higher affinity with the fauna of West African and nearby freshwater ecoregions than it has with fauna of other regions of the Congo Basin and Central Africa.

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2

Mannu, F., P. Arese, MD Cappellini, G. Fiorelli, M. Cappadoro, G. Giribaldi, and F. Turrini. "Role of hemichrome binding to erythrocyte membrane in the generation of band-3 alterations in beta-thalassemia intermedia erythrocytes." Blood 86, no. 5 (September 1, 1995): 2014–20. http://dx.doi.org/10.1182/blood.v86.5.2014.bloodjournal8652014.

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Nine splenectomized, hematologically well-compensated beta-thalassemia intermedia patients randomly chosen from a pool of 60 similar patients were studied. Membrane proteins solubilized with nondenaturing detergent C12E8 were gel filtered on Sepharose CL-6B (Pharmacia Fine Chemicals, Uppsala, Sweden). Fractions containing higher than 4,000-kD molecular-weight aggregates were isolated and analyzed. Four patients had remarkably increased amounts of membrane-bound hemichromes and Igs. In those patients, band 3 underwent oxidative modifications such as aggregation and a decrease in sulfhydryl groups. The other five patients had low amounts of membrane-bound hemichromes and less modifications of band 3. The same band-3 modifications could be reproduced by challenging normal membranes with artificially generated hemichromes or with hemolysates prepared from thalassemic erythrocytes of the high-hemichrome group. Addition of reduced glutathione to the challenged membranes did not hinder hemichrome binding, but prevented oxidative modifications of band 3 and Ig binding to high-molecular- weight band-3 aggregates. Hemichrome binding to band 3, hemichrome- mediated oxidation of band-3 cytoplasmic domains, generation of high- molecular-weight band-3 aggregates, and enhanced opsonization by anti- band-3 antibodies is a possible sequence of events leading to phagocytic removal of erythrocytes in thalassemia.

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3

Kühme, Wolfdietrich. "Chemisch ausgelöste Brutpflege- und Schwarmreaktionen bei Hemichromis bimaculatus (Pisces)." Zeitschrift für Tierpsychologie 20, no. 6 (April 26, 2010): 688–704. http://dx.doi.org/10.1111/j.1439-0310.1963.tb01183.x.

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4

Burchard, John, and Wolfgang Wickler. "Eine neue Form des Cichliden Hemichromis fasciatus PETERS (Pisces: Perciformes)." Journal of Zoological Systematics and Evolutionary Research 3, no. 3-4 (April 27, 2009): 277–83. http://dx.doi.org/10.1111/j.1439-0469.1965.tb00941.x.

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5

Hyslop, E. J. "First occurrence of Acanthogyrus tilapiae (Baylis 1948) in Hemichromis species." Journal of Fish Biology 33, no. 3 (September 1988): 491–92. http://dx.doi.org/10.1111/j.1095-8649.1988.tb05491.x.

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6

Huysseune, Ann, and Jean-Yves Sire. "Ultrastructural observations on chondroid bone in the teleost fish Hemichromis bimaculatus." Tissue and Cell 22, no. 3 (January 1990): 371–83. http://dx.doi.org/10.1016/0040-8166(90)90011-w.

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7

Tsamesidis, Ioannis, Karine Reybier, Giuseppe Marchetti, Maria Carmina Pau, Patrizia Virdis, Claudio Fozza, Francoise Nepveu, Philip S. Low, Francesco Michelangelo Turrini, and Antonella Pantaleo. "Syk Kinase Inhibitors Synergize with Artemisinins by Enhancing Oxidative Stress in Plasmodium falciparum-Parasitized Erythrocytes." Antioxidants 9, no. 8 (August 14, 2020): 753. http://dx.doi.org/10.3390/antiox9080753.

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Although artemisinin-based combination therapies (ACTs) treat Plasmodium falciparum malaria effectively throughout most of the world, the recent expansion of ACT-resistant strains in some countries of the Greater Mekong Subregion (GMS) further increased the interest in improving the effectiveness of treatment and counteracting resistance. Recognizing that (1) partially denatured hemoglobin containing reactive iron (hemichromes) is generated in parasitized red blood cells (pRBC) by oxidative stress, (2) redox-active hemichromes have the potential to enhance oxidative stress triggered by the parasite and the activation of artemisinin to its pharmaceutically active form, and (3) Syk kinase inhibitors block the release of membrane microparticles containing hemichromes, we hypothesized that increasing hemichrome content in parasitized erythrocytes through the inhibition of Syk kinase might trigger a virtuous cycle involving the activation of artemisinin, the enhancement of oxidative stress elicited by activated artemisinin, and a further increase in hemichrome production. We demonstrate here that artemisinin indeed augments oxidative stress within parasitized RBCs and that Syk kinase inhibitors further increase iron-dependent oxidative stress, synergizing with artemisinin in killing the parasite. We then demonstrate that Syk kinase inhibitors achieve this oxidative enhancement by preventing parasite-induced release of erythrocyte-derived microparticles containing redox-active hemichromes. We also observe that Syk kinase inhibitors do not promote oxidative toxicity to healthy RBCs as they do not produce appreciable amounts of hemichromes. Since some Syk kinase inhibitors can be taken daily with minimal side effects, we propose that Syk kinase inhibitors could evidently contribute to the potentiation of ACTs.

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8

Coss, Richard G. "Development of Face Aversion by the Jewel Fish (Hemichromis bimaculatus, Gill 1862)." Zeitschrift für Tierpsychologie 48, no. 1 (April 26, 2010): 28–46. http://dx.doi.org/10.1111/j.1439-0310.1978.tb00246.x.

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9

Hyslop, E. J. "Aspects of the biology of Hemichromis bimaculatus from a small stream in Nigeria." Journal of Fish Biology 31, no. 6 (December 1987): 745–51. http://dx.doi.org/10.1111/j.1095-8649.1987.tb05277.x.

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10

Belfiore, Natalia M., and Pamela J. Schofield. "Genetic Characterization of Non-Native African Jewelfish, Hemichromis letourneuxi Sauvage 1880, in Florida." Southeastern Naturalist 18, no. 4 (November 1, 2019): 561. http://dx.doi.org/10.1656/058.018.0406.

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11

Rashed, Mohamed, Ashraf Abd EL-Rasek, Ezzat Badawy, and Yasser Saad. "GENETIC SIGNATURE OF SOME HEMICHROMIS BJMACULATUS FISH POPULATIONS BASED ON MUSCLE PROTEIN POLYMORPHISM." Egyptian Journal of Aquatic Biology and Fisheries 11, no. 1 (January 1, 2007): 83–100. http://dx.doi.org/10.21608/ejabf.2007.1915.

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12

Huysseune, A., and J. Y. Sire. "Structure and development of first-generation teeth in the cichlid Hemichromis bimaculatus (Teleostei, Cichlidae)." Tissue and Cell 29, no. 6 (December 1997): 679–97. http://dx.doi.org/10.1016/s0040-8166(97)80044-4.

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13

Quilhac, Alexandra, and Jean-Yves Sire. "Spreading, proliferation, and differentiation of the epidermis after wounding a Cichlid fish,Hemichromis bimaculatus." Anatomical Record 254, no. 3 (March 1, 1999): 435–51. http://dx.doi.org/10.1002/(sici)1097-0185(19990301)254:3<435::aid-ar15>3.0.co;2-d.

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14

Christ, Hildegard. "Effects of MET-ENK, substance P and SRIF on the behavior of Hemichromis bimaculatus." Peptides 6, no. 1 (January 1985): 139–48. http://dx.doi.org/10.1016/0196-9781(85)90090-7.

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15

N, Ikiriko, Robert B, and Amuzie C. C. "Assessment of Ectoparasites and Heavy Metal Concentrations in Hemichromis Fasciatus, Liza Falcipinnis and Sarotherodon Galileus." Journal La Lifesci 1, no. 5 (December 26, 2020): 12–21. http://dx.doi.org/10.37899/journallalifesci.v1i5.243.

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Ectoparasites and heavy metal pollution pose health risks to both wild and aquaculture fish species. Here, we examine the ectoparasites of fish species (Hemichromis fasciatus, Liza falcipinnis and Sarotherodon galileus) from Abalama and Ilelema locations of the Buguma Creek, Rivers State, Nigeria, over a period of six months (February to July, 2020). Fish tissues (muscles, gills and gut) were also examined for heavy metals (Cr, Cd and Pb). Parasitological investigations were done following standard procedures, as well as the heavy metal analysis which was done using atomic absorption spectrophotometer after dry ashing-acid digestion. Two ectoparasites were isolated: Zeylanicobdella arugamensis from L. falcipinnis at both locations and Cymothoa exigua from H. fasciatus at Ilelema. In surface water, Cr concentration was <0.003µg/l throughout the study period; Cd concentrations ranged between 0.06µg/l and 0.09µg/l at both locations, while Pb values were 0.29µg/l - 0.64µg/l at Abalama, and 0.56µg/l – 0.71µg/l at Ilelema. These values were within international acceptable standards. In fish tissues, however, Cr values were <0.003µg/g in both locations throughout the study period. At Abalama, Cd ranged between 7.18µg/g and 8.15µg/g, and Pb between 72.83µg/g and 92.23µg/g. At Ilelema, Cd concentrations were between 7.56µg/g and 8.67µg/g while Pb values ranged between 78.32µg/g and 92.88µg/g. Differences in heavy metal concentrations in both water and fish tissues between both locations were not statistically significant (p>0.05). All fish species and tissues bioaccumulated appreciable concentrations of the heavy metals. Cr in fish tissues was within permissible limits, but all Cd and Pb values exceeded international permissible limits.

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16

Quilhac, Alexandra, and Jean-Yves Sire. "Restoration of the subepidermal tissues and scale regeneration after wounding a cichlid fish,Hemichromis bimaculatus." Journal of Experimental Zoology 281, no. 4 (July 1, 1998): 305–27. http://dx.doi.org/10.1002/(sici)1097-010x(19980701)281:4<305::aid-jez6>3.0.co;2-s.

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17

Firda, Arlian. "IDENTIFIKASI SPESIES IKAN DI WADUK CIRATA, JAWA BARAT." Bio-Lectura 2, no. 2 (October 25, 2015): 150–63. http://dx.doi.org/10.31849/bl.v2i2.325.

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ABSTRAKS: Ikan menempati berbagai bentuk ekosistem perairan seperti laut, payau dan air tawar. Sekitar 43% dari jumlah total dari semua jenis ikan, menempati air tawar. Konstruksi Reservoir menyebabkan perubahan topografi dan hidrologi air alami. Altaration topografi berhubungan dengan keragaman spesies. Waduk Cirata merupakan waduk utama di Indonesia, terbentuk dari pembendungan Sungai Citarum. Jumlah spesies ikan asli di sungai Citarum sebelum pembendungan lebih dari 20 spesies. Studi ini menemukan 16 spesies ikan, dengan sembilan spesies asli, adalah; Barbonymus balleroides, Rasbora argyrotaenia, Osteochilus vittatus, Mystacoleucus marginatus, Hampala macrolepidota, Hemibagrus nemurus, Mystus nigriceps, Oxyleotris marmorata, Parambasis siamensis, serta tujuh spesies non-pribumi adalah; Cyprinus carpio, Oreochromis niloticus, Hemichromis elongatus, Amphilopus citrinellus, Chanos chanos, bawal, Hypostomus plecostomus. Spesies ikan asli yang tidak ditemukan dalam penelitian sebelumnya adalah Barbonymus gonionotus, Puntius binotatus, dan Chana striata.

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18

Georges, Blahoua Kassi, Adou Yedehi Euphrasie, Gogbé Zeré Marius, and N’Douba Valentin. "Régime Alimentaire De Hemichromis Fasciatus (Perciformes, Cichlidae) Dans Le Lac De Barrage Hydroélectrique D’ayamé 2 (Côte D’ivoire)." European Scientific Journal, ESJ 13, no. 30 (October 31, 2017): 126. http://dx.doi.org/10.19044/esj.2017.v13n30p126.

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The diet of Hemichromis fasciatus (Perciformes, Cichlidae) was studied in the lake dam of Ayame 2 (Côte d'Ivoire) from September 2015 to August 2016. A total of 141 specimens were captured using gill nets and hawks. The relative importance of food index has been calculated to assess the relative abundance of the preys. The standard length of fish varied between 70 mm and 250 mm. The global percentage of emptiness and intestinal coefficient mean were 23.40 % and 1.35 ± 0.48 respectively. The food spectra constituted of fishes, insects, arachnids and plants debris showing that this species an omnivorous fish with predatory fish tendency. The comparison of the food habits between size ranges (LS ≤ 110 mm and LS ˃ 110 mm) did not show any significant difference. But, a significant variation of the diet according the sexes and seasons was observed.

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19

Hill, Jeffrey E. "Collapse of a reproducing population of non-native African jewelfish (Hemichromis letourneuxi) in a Florida lake." NeoBiota 29 (March 16, 2016): 35–52. http://dx.doi.org/10.3897/neobiota.29.7213.

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20

Langston, Jacqueline N., Pamela J. Schofield, Jeffrey E. Hill, and William F. Loftus. "Salinity Tolerance of the African Jewelfish Hemichromis letourneuxi, a Non-native Cichlid in South Florida (USA)." Copeia 2010, no. 3 (September 2010): 475–80. http://dx.doi.org/10.1643/cp-09-069.

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21

Ahrens, Katja, and Mario F. Wullimann. "Hypothalamic inferior lobe and lateral torus connections in a percomorph teleost, the red cichlid (Hemichromis lifalili)." Journal of Comparative Neurology 449, no. 1 (June 6, 2002): 43–64. http://dx.doi.org/10.1002/cne.10264.

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22

Kouadio, Akissi Nathalie, Yao Aristide Konan, Stanislas Silvain Yao, Zeré Marius Gogbé, and Gouli Gooré Bi. "Food and feeding habits of Hemichromis fasciatus Peters, 1857 and Heterotis niloticus (Cuvier, 1829) in lake Ehuikro (Côte d’Ivoire)." International Journal of Biological and Chemical Sciences 13, no. 7 (February 11, 2020): 3039–52. http://dx.doi.org/10.4314/ijbcs.v13i7.6.

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The main of this study was to compare the diet of Hemichromis fasciatus (Perciformes, Cichlidae) and Heterotis niloticus (Osteoglossiformes, Arapaimidae) in Lake Ehuikro (Bongouanou, Ivory Coast). Ffish were caught using gillnets between July 2017 and June 2018. A total of 206 stomachs of H. fasciatus and 71 stomachs of H. niloticus were examined and the relative importance index (RI) was used to analyze the importance of different items. Results indicate that both species are omnivorous tending towards insectivorous with a predominance of Chaoboridae. Despite the overlap obtained in diet of both species (Cλ = 0.89), the ecological niche was small and wide in H. fasciatus and H. niloticus, respectively. Dietary variations indicated ontogenic changes in the first specie and seasonal changes in the second specie. Proportion of mineral fraction observed in stomach contents suggests pelagic feeding behavior in H. fasciatus and benthic behavior in H. niloticus.Keywords: Diet, fish, omnivorous, insectivorous, ecological niche.

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23

López-Crespo, RA, LC Martínez-Chavarría, AT Lugo-García, LP Romero-Romero, LJ García-Márquez, and A. Reyes-Matute. "Outbreak of francisellosis (Francisella noatunensis subsp. orientalis) in cultured neon jewel cichlids Hemichromis bimaculatus from Morelos, Mexico." Diseases of Aquatic Organisms 137, no. 2 (December 19, 2019): 125–30. http://dx.doi.org/10.3354/dao03429.

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24

de Lourdes Lozano-Vilano, MarÍa, Armando J. Contreras-Balderas, and MarÍa Elena GarcÍa-RamÍrez. "ERADICATION OF SPOTTED JEWELFISH, HEMICHROMIS GUTTATUS, FROM POZA SAN JOSÉ DEL ANTEOJO, CUATRO CIÉNEGAS BOLSÓN, COAHUILA, MEXICO." Southwestern Naturalist 51, no. 4 (December 2006): 553–55. http://dx.doi.org/10.1894/0038-4909(2006)51[553:eosjhg]2.0.co;2.

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25

Sire, Jean-Yves. "The same cell lineage is involved in scale formation and regeneration in the teleost fish Hemichromis bimaculatus." Tissue and Cell 21, no. 3 (January 1989): 447–62. http://dx.doi.org/10.1016/0040-8166(89)90058-x.

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26

Van der heyden, C., F. Allizard, J. Y. Sire, and A. Huysseune. "Tooth development in vitro in two teleost fish, the cichlid Hemichromis bimaculatus and the cyprinid Danio rerio." Cell and Tissue Research 321, no. 3 (June 21, 2005): 375–89. http://dx.doi.org/10.1007/s00441-004-1036-x.

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27

Souza, Augusto César Paes, Karina Motta Melo, Luana França Calandrini de Azevedo, Andryo Orfi de Almada Vilhena, Cleusa Yoshiko Nagamachi, and Júlio César Pieczarka. "Lethal and sublethal exposure of Hemichromis bimaculatus (Gill, 1862) to malachite green and possible implications for ornamental fish." Environmental Science and Pollution Research 27, no. 26 (June 11, 2020): 33215–25. http://dx.doi.org/10.1007/s11356-020-09615-1.

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28

Mendoza-Franco, Edgar F., Juan Manuel Caspeta-Mandujano, and Marina Tapia Osorio. "Ecto- and endo-parasitic monogeneans (Platyhelminthes) on cultured freshwater exotic fish species in the state of Morelos, South-Central Mexico." ZooKeys 776 (July 26, 2018): 1–12. http://dx.doi.org/10.3897/zookeys.776.26149.

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An extensive parasitological study of 365 freshwater exotic fish specimens belonging to 13 species of seven families (Cichlidae, Cyprinidae, Osphronemidae, Pangasidae, Poeciliidae, Characidae, and Loricariidae) collected from 31 Aquaculture Production Units (APU) from Central Mexico revealed the occurrence of 29 ecto- and endo-parasitic monogeneans found on gills and stomachs: Cichlidogyrussclerosus, C.thurstonae, C.tilapiae, Cichlidogyrus sp. 1, Cichlidogyrus sp. 2, Enterogyruscoronatus, E.malmbergi, Gusseviaspiralocirra, Sciadicleithrumiphthimum, Sciadicleithrum sp., Scutogyruslongicornis (all Dactylogyridae), Gyrodactyluscichlidarum, and G.yacatli (Gyrodactylidae) on Oreochromisniloticus, Pterophyllumscalare and Hemichromis sp. (Cichlidae); Dactylogyrusbaueri, D.formosus, D.intermedius, D.vastator, D.extensus, Dactylogyrus sp. (all Dactylogyridae), and G.kobayashii on Carassiusauratus, Cyprinuscarpio and Ctenopharyngodonidella (Cyprinidae); Trianchoratusacleithrium and T.trichogasterium (Dactylogyridae) on Trichogastertrichopterus (Osphronemidae); Thaparocleiduscaecus, T.siamensis (Dactylogyridae), and Dactylogyridae sp. on Pangasianodonhypophthalmus (Pangasidae); G.poeciliae on Poeciliareticulata (Poeciliidae); Diaphorocleidusarmillatus (Dactylogyridae) on Gymnocorymbusternetzy (Characidae); Unilatusunilatus (Dactylogyridae) and Gyrodactylidae sp. on Hypostomus sp. (Loricariidae). The paramount importance of the establishment of these monogeneans due to the importation/exportation of non-native ornamental and other exotic host fish species cultured for food in Mexico is briefly discussed. Quarantine is recommended for all transferred host species.

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29

Schofield, Pamela J., Daniel H. Slone, Denise R. Gregoire, and William F. Loftus. "Effects of a non-native cichlid fish (African jewelfish, Hemichromis letourneuxi Sauvage 1880) on a simulated Everglades aquatic community." Hydrobiologia 722, no. 1 (October 19, 2013): 171–82. http://dx.doi.org/10.1007/s10750-013-1697-0.

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30

Schofield, Pamela J., William F. Loftus, Robert M. Kobza, Mark I. Cook, and Daniel H. Slone. "Tolerance of nonindigenous cichlid fishes (Cichlasoma urophthalmus, Hemichromis letourneuxi) to low temperature: laboratory and field experiments in south Florida." Biological Invasions 12, no. 8 (November 22, 2009): 2441–57. http://dx.doi.org/10.1007/s10530-009-9654-6.

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31

Nyom, Arnold R. Bitja, Hermann I. Kitio, Samuel D. Njom, Antoine Pariselle, Jos Snoeks, and Charles F. Bilong Bilong. "Morphological variations, length-weight relationships and condition factors of Hemichromis camerounensis (Cichliformes, Cichlidae) in three lakes in northern Cameroon." International Journal of Fisheries and Aquatic Studies 9, no. 3 (May 1, 2021): 139–45. http://dx.doi.org/10.22271/fish.2021.v9.i3b.2500.

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32

OMONIYI, I. T., and O. C. OJELADE. "PARASITES OF THE CICHLID FISHES IN WATER RESERVOIR OF FEDERAL UNIVERSITY OF AGRICULTURE, ABEOKUTA, NIGERIA." Journal of Agricultural Science and Environment 17, no. 2 (May 16, 2019): 20–27. http://dx.doi.org/10.51406/jagse.v17i2.1831.

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A survey of parasites of Tilapia species (Family; Cichlidae) was carried out at the Federal University of Agriculture, Abeokuta Reservoir. A total of 150 specimens belonging to four genera and species were examined for parasites. Of the total number examined 16.0% were infected with various types of parasites. Parasites encountered during the study included flagellate protozoan, Ichtyobodonecatrix (96.0%), species of annelid, Piscicola sp.(1.6%), species of nematode, Cucullanus sp.(1.6%), and species of cestode, Caryophyllaeidessp (0.8%). This result showed low prevalence of infection as well as low parasites diversity. The prevalence of infection was highest in Oreochromis niloticus (29.0%) and followed in descending order by Hemichromis fasciatus (16.7%), Sarotherodon galilaeus (14.3%)and Tilapia zillii (10.5%). The skin (60.7%), gills (36.9%), stomach (1.6%) and intestine (0.8%) were the locations infected and the skin supported the highest burden. The result also revealed that there were no significant differences between the size/age (X2=0.44; p>0.05)and sex (X2=1.38; p>0.05) and the degree of parasitic infection in this group of fishes. The economic and public health implications of these results in relation to fish-man interactions were discussed.

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33

Wangboje, O. M., and F. A. Oguzie. "An Evaluation of Polycyclic Aromatic Hydrocarbons in Hemichromis fasciatus (Peters, 1857) from an Urban Reservoir in Southern Nigeria." Tropical Freshwater Biology 22, no. 1 (September 29, 2014): 35. http://dx.doi.org/10.4314/tfb.v22i1.4.

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34

Ibor, Oju Richard, George Eni, Andem Bassey Andem, Akanimo Joseph, and Azubuike Victor Chukwuka. "Sexual dimorphism in black jaw tiliapia (Sarotherodon melanotheron) and banded jewelfish (Hemichromis fasciatus) from the Great Kwa River, Calabar, Nigeria." Croatian Journal of Fisheries 75, no. 4 (December 1, 2017): 122–31. http://dx.doi.org/10.1515/cjf-2017-0016.

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AbstractIn this study, the pattern and magnitude of sexual dimorphic differences have been investigated in black jaw tilapia (Sarotherodon melanotheron) (n = 160; 74 males and 86 females) and banded jewelfish (Hemichromis fasciatus) (n = 120; 42 males and 78 females) from the Great Kwa River, Calabar, Nigeria. Fish samples were collected between July and December 2015. Fourteen morphometric variables, including body weight, total length, standard length, body depth, cheek depth, pre-orbital length, postorbital length, pectoral fin length (right and left), pelvic fin length (right and left), head length, gonad weight, eye diameter and four meristic variables, including number of pectoral fins (right and left) and number of pelvic fins (right and left), were taken using standard methods. Size-adjusted morphometric measurements subjected to step-wise discriminant function analysis were used to determine predictor variables to morphologically differentiate sexes for both species; magnitude of dimorphism between sexes was estimated using percentage classification accuracy of the discriminant function analysis. From the discriminant function analysis, the pectoral fin length and gonad weight positively contributed significantly to morphometric dimorphism (magnitude=69.2%) in male and femaleS. melanotheronsuggesting adaptation for reproductive function; while forH. fasciatusthe body depth and standard length were important contributors to sexual dimorphism (magnitude=84.2%) suggesting size dimorphism for aggressiveness, territorial behavior and improving swimming performance. Overall, our results indicate that the different magnitude of sexual dimorphism between the two species could be attributable to the type and functional role of sexual dimorphic traits.

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Sidi Imorou, Rachad, Alphonse Adite, Hamidou Arame, and Pejanos Stanislas Sonon. "Aspects of life history patterns of the cichlid fish Hemichromis fasciatus Peters, 1857 from Okpara Stream, Northern Benin, West Africa." Aquatic Research 3, no. 2 (2020): 110–23. http://dx.doi.org/10.3153/ar20010.

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Sire, Jean-Yves, and Ann Huysseune. "Fine structure of the developing frontal bones and scales of the cranial vault in the cichlid fish Hemichromis bimaculatus (Teleostei, Perciformes)." Cell & Tissue Research 273, no. 3 (September 1993): 511–24. http://dx.doi.org/10.1007/bf00333705.

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Krysko, Kenneth L., Stephen J. Walsh, and Robert H. Robins. "The native Florida Green Watersnake, Nerodia floridana (Goff 1936), preying upon the nonindigenous African Jewelfish, Hemichromis letourneuxi Sauvage 1880, in Florida." Reptiles & Amphibians 19, no. 3 (September 1, 2012): 161–62. http://dx.doi.org/10.17161/randa.v19i3.13898.

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Obayemi, O. E., and O. O. Komolafe. "HISTOPATHOLOGY STUDIES OF SELECTED ORGANS OF Hemichromis fasciatus INHABITING IGUN GOLD MINING AND OPA RESERVOIRS, OSUN STATE, NIGERIA: A COMPARATIVE STUDY." Open Journal of Environmental Research (ISSN: 2734-2085) 1, no. 1 (March 10, 2020): 21–32. http://dx.doi.org/10.52417/ojer.v1i1.69.

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This study examined the histopathological alterations in the gills, fillet and liver of Hemichromis fasciatus in Igun reservoir (located in an abandoned goldmine area) compared to those of Opa reservoir. Life fish species were collected from Opa and Igun reservoirs and identified in the laboratory. Techniques based on histological analyses were done on the organs and photomicrographs taken using digital binocular compound LED microscope. Epithelial lifting and hypertrophy of lamellae were observed in the gills of H. fasciatus in Opa reservoir and compared to rupture of gill epithelium, rupture of chloride cell, fusion, hyperplasia, curling of lamellae in H. fasciatus of Igun reservoir. The fillet of H. fasciatusin Opa and Igun reservoirs revealed splitting and atrophy of muscle bundles. Also, parasite cyst and necrosis were observed in the fillet of H. fasciatus of Igun reservoir compared to degeneration in muscle bundles in the fish of Opa reservoir. Similarly, the liver of H. fasciatus in Igun and Opa reservoirs showed splitting at the wall of central vein, hepatopancreas and liver cells degeneration. Moreover, nucleus hypertrophy was also identified in the liver of H. fasciatus in Opa reservoir compared to vascular congestion in the central vein, bile duct, portal vein and portal artery of H. fasciatus in Igun reservoir. The study therefore concluded that H. fasciatus specimens in Igun reservoir were histopathologically unhealthy as compared with those of Opa reservoir probably due to the high level of pollution resulting in bioaccumulation of heavy metals in Igun reservoir samples. Obayemi, O. E | Department of Zoology, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria

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Oluwadamilare Emmanuel, Obayemi, and Komolafe Olaniyi Olusola. "Histopathology Studies of Selected Organs of Hemichromis Fasciatus [1] Inhabiting Igun Gold Mining and Opa Reservoirs, South Western Nigeria: A Comparative Study." International Journal of Advances in Life Science and Technology 4, no. 1 (2020): 1–10. http://dx.doi.org/10.18488/journal.72.2020.41.1.10.

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Nack Jacques, Mbondo Jonathan Armel, Bassock Bayiha Etienne Didier, and Bilong Bilong Charles Félix. "Epidemiological study of Enterogyrus melenensis, stomach parasitic helminth of Hemichromis fasciatus in the Mefou hydrographic system (South-Cameroon, Africa); effect of the environment." World Journal of Advanced Research and Reviews 7, no. 2 (August 30, 2020): 025–33. http://dx.doi.org/10.30574/wjarr.2020.7.2.0275.

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Adeosun, Festus Idowu. "Annual Pattern on Abundance and Sex Ratio Distribution of Selected Fish Fauna of Ikere Gorge Reservoir, Oyo State, Nigeria." Borneo Journal of Resource Science and Technology 9, no. 1 (June 26, 2019): 1–13. http://dx.doi.org/10.33736/bjrst.1580.2019.

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Sex ratio affects the growth of wild population, thus, with the declining wild fish population, the study was designed to determine the effect of seasons on the sex ratio of fish population from Ikere Gorge, Nigeria for 18 months. Fish composition, diversity, distribution and abundance were determined according to standard methods. Sexes were determined and sex ratio was calculated using a standard method. A total of 5,823 fish specimens were caught during the period. The captured fish species were identified and classified into 34 species belonging to 13 families. The species richness was higher in the dry months than in the wet months. Fish diversity indices and evenness revealed a better diverse and even ecosystem in the wet season than the dry season. A marked significant difference (p < 0.05) was observed between the species in the dry months than the wet season. Chrysichthyes nigrodigitatus (35.07±7.59a) was significantly (p < 0.05) more abundant than the other species in the dry season. The sex ratio was skewed in favour of the female populations for C. nigrodigitatus, Tilapia melanopleura and Sarotherodon galilaeus but the reverse was the case for L. niloticus population. No monthly variation was observed in sex ratio of the species. The fish fauna from Ikere Gorge showed marked variations in the catch composition between the dry and wet months. C. nigrodigitatus and the Cichlids (Hemichromis fasciatus, S. galilaeus, Tilapia macrocephla and T. melanopleura) were present all year.

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Marva, E., and RP Hebbel. "Denaturing interaction between sickle hemoglobin and phosphatidylserine liposomes." Blood 83, no. 1 (January 1, 1994): 242–49. http://dx.doi.org/10.1182/blood.v83.1.242.242.

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Abstract It is hypothesized that abnormal interaction between sickle hemoglobin (HbS) and erythrocyte membrane lipid might promote deposition of denatured hemoglobin (hemichrome) on the membrane. We compared the interaction of HbS and normal HbA with large unilamellar phosphatidylserine (PS) liposomes under low salt/pH conditions. Admixture of oxyHb and dioleoyl-PS resulted in loss of absorbance at 412 nm, the apparent first order rate constant for which was .25 +/- 0.02 hour-1 for HbA and .85 +/- 0.18 hour-1 for HbS. This was ascribable largely to formation of metHb and hemichromes and was accompanied by some actual transfer of heme from hemoglobin to lipid phase. By comparison, admixture of oxyHb with liposomes made from bovine brain PS having unsaturated acyl chains promoted even faster absorbance loss if the starting liposomal material contained detectable peroxidation by-product. In such cases, actual heme destruction developed with accompanying liberation of free iron and promotion of lipidperoxidation. Fluorescence quenching experiments indicate that hemoglobin/lipid interaction is characterized by very rapid initial electrostatic interaction, followed by development of irreversible changes. Similar changes still occur under conditions of physiologic salt/pH, but they develop much more slowly. The 3.4-fold faster oxidation of HbS versus HbA on lipid observed here represents an additional augmentation of the disparity in oxidation rates for hemoglobins in solution (1.7-fold faster for HbS than for HbA) observed previously. The accelerated promotion of Hb denaturation resulting from lipid contact may help explain deposits of hemichrome on sickle red blood cell membranes, particularly because these cells are in double jeopardy by virtue of having both the mutant HbS and abnormal amounts of peroxidized membrane lipid.

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Marva, E., and RP Hebbel. "Denaturing interaction between sickle hemoglobin and phosphatidylserine liposomes." Blood 83, no. 1 (January 1, 1994): 242–49. http://dx.doi.org/10.1182/blood.v83.1.242.bloodjournal831242.

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It is hypothesized that abnormal interaction between sickle hemoglobin (HbS) and erythrocyte membrane lipid might promote deposition of denatured hemoglobin (hemichrome) on the membrane. We compared the interaction of HbS and normal HbA with large unilamellar phosphatidylserine (PS) liposomes under low salt/pH conditions. Admixture of oxyHb and dioleoyl-PS resulted in loss of absorbance at 412 nm, the apparent first order rate constant for which was .25 +/- 0.02 hour-1 for HbA and .85 +/- 0.18 hour-1 for HbS. This was ascribable largely to formation of metHb and hemichromes and was accompanied by some actual transfer of heme from hemoglobin to lipid phase. By comparison, admixture of oxyHb with liposomes made from bovine brain PS having unsaturated acyl chains promoted even faster absorbance loss if the starting liposomal material contained detectable peroxidation by-product. In such cases, actual heme destruction developed with accompanying liberation of free iron and promotion of lipidperoxidation. Fluorescence quenching experiments indicate that hemoglobin/lipid interaction is characterized by very rapid initial electrostatic interaction, followed by development of irreversible changes. Similar changes still occur under conditions of physiologic salt/pH, but they develop much more slowly. The 3.4-fold faster oxidation of HbS versus HbA on lipid observed here represents an additional augmentation of the disparity in oxidation rates for hemoglobins in solution (1.7-fold faster for HbS than for HbA) observed previously. The accelerated promotion of Hb denaturation resulting from lipid contact may help explain deposits of hemichrome on sickle red blood cell membranes, particularly because these cells are in double jeopardy by virtue of having both the mutant HbS and abnormal amounts of peroxidized membrane lipid.

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Pérsico, María Marta, Federico Alcides Cecchi, Aldo Nahuel Zanazzi, Arturo Asiain, Brian Nahuel Tomaselli, Fabiana Pérez, María Inés Prario, Paula Waldmann, Juan Carlos Mallo, and María Laura Patat. "Crecimiento del pez ornamental Hemichromis bimaculatus (Cichlidae) en un Sistema de Recirculación de Agua, con incorporación en el alimento de residuos industriales y algas." Revista Tecnología y Ciencia, no. 41 (August 3, 2021): 105–17. http://dx.doi.org/10.33414/rtyc.41.105-117.2021.

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El presente trabajo tuvo como objetivo evaluar el crecimiento de juveniles del pez ornamental H. bimaculatus, Cichlidae, utilizando residuos industriales de langostino argentino y cebada cervecera, con complemento de algas en el alimento. El cultivo se realizó en un sistema de recirculación de agua a escala de laboratorio. Se evaluaron los parámetros peso y largo total de los individuos, la supervivencia, la calidad del agua y el funcionamiento del sistema empleado. Si bien se hallaron diferencias significativas (p ˂0,05) para ambas variables al compararlas con el alimento control, 47,5 % de proteínas, el crecimiento con el alimento alternativo fue positivo, tasa de crecimiento específico 2 mg/día, y la sobrevivencia muy elevada, 98%. Los residuos de langostino y cebada podrían ser utilizados como materias primas en alimentos formulados para esta especie, reemplazando parcialmente a la harina de pescado, de forma más amigable con el ambiente y con alta disponibilidad regional.

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Díaz-Ferguson, Edgardo. "Development of molecular markers for eDNA detection of the invasive African jewelfish (Hemichromis letourneuxi): a new tool for monitoring aquatic invasive species in National Wildlife Refuges." Management of Biological Invasions 5, no. 2 (June 2014): 121–31. http://dx.doi.org/10.3391/mbi.2014.5.2.05.

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Bitja-Nyom, Arnold Roger, Jean-François Agnèse, Antoine Pariselle, Charles Félix Bilong-Bilong, André Gilles, and Jos Snoeks. "A systematic revision of the five-spotted Hemichromis complex (Cichliformes: Cichlidae) from West Africa and Lower Guinea, with the description of a new species from Cameroon." Hydrobiologia 848, no. 16 (January 22, 2021): 3779–803. http://dx.doi.org/10.1007/s10750-020-04506-5.

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47

Merlino, Antonello, Cinzia Verde, Guido di Prisco, Lelio Mazzarella, and Alessandro Vergara. "Reduction of ferric hemoglobin fromTrematomus bernacchiiin a partial bis-histidyl state produces a deoxy coordination even when encapsulated into the crystal phase." Spectroscopy 22, no. 2-3 (2008): 143–52. http://dx.doi.org/10.1155/2008/328463.

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Crystallographic and spectroscopic evidences on Antarctic fish hemoglobins (AFHbs) have revealed that their ferric tetramers at physiological pH are in a mixed |α(aquo-met)/β(bis-histidyl) coordination state and show a quaternary structure intermediate between the classical R and T states (H state). Ferric bis-histidyl adducts (hemichromes) have been also observed in some mammalian Hbs. In order to clarify whether hemichrome in AFHbs can be converted into a ferrous bis-histidyl adduct (hemochrome), at least in the crystal phase, chemical reduction of ferric hemoglobins fromTrematomus bernacchii(HbTb) single crystals has been followed via Raman microscopy. The results of this analysis reveal that in HbTb, upon reduction, the bis-histidyl coordination is disrupted in favor of a penta-coordinated ferrous deoxy state, with no evidence of hemochrome. These data are in agreement with UV/Vis absorption spectra in solution. Furthermore, our data are also indirectly supported by the observation that upon reduction with dithionite, the ferric HbTb crystals crack and lose their diffraction power: in the crystalline state, the quaternary structure transition from the H to the T state is not compatible with the crystal packing. Altogether these data indicate that if bis-histidyl adducts have a functional significance in AFHbs, this function refers to a stable ferric state, or to a transient, though never detected, ferrous species.

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48

Dembe Louvinguila Tenda, Hélène, Armel Ibala Zamba, Joseph Goma-Tchimbakala, Lérège Batiabo Mikembi, Honest Freedom Poaty Ngot, and Victor Mamonekene. "Effets saisonniers sur les relations poids-longueurs et coefficients de condition pour 16 espèces de poissons de la Lagune Mvassa, basse Guinée, République du Congo." Journal of Animal & Plant Sciences 44.1 (April 30, 2020): 7540–52. http://dx.doi.org/10.35759/janmplsci.v44-1.1.

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Objectifs : La présente étude a été initiée pour établir les relations poids-longueur et les facteurs de condition de Ethmalosa fimbriata, Sardinella maderensis, Coptodon guinensis, Oreochromis schwebischi, Neochelon falcipinnis, Mugil cephalus, Parachelon grandisquamis, Eucinostomus melanopterus, Hemichromis elongatus, Pomadasys jubelini, Eleotris daganensis, Bathygobius soporator, Trachinotus teraia, Lutjanus goreensis, Mugil banannensis, et Sarotherodon melanotheron, 16 espèces les plus abondantes de la lagune Mvassa en République du Congo. Méthodologie et résultats : Les échantillonnages des poissons ont été réalisés sur 9 stations à l’aide des filets maillants de 8, 10, 20 et 30 mm de côté de la maille. Les relations poidslongueur ont été réalisées en utilisant l’équation P = aLSb et leurs coefficients de condition en utilisant l’équation K = 100*(P ⁄ LSb ). Au total, 1566 spécimens, réparties en 5 ordres, 8 familles, 16 espèces dont 10 ont été capturées en saison sèche, 14 en saison des pluies et 8 espèces communes pour les deux saisons ont été utilisés dans le cadre de cette étude. Le coefficient de détermination r 2 était significatif pour les deux saisons et variait de 0,91 pour Neochelon falcipinnis et 0,99 pour Pomadasys jubelini avec une moyenne de 0,97 ± 0,02. En saison sèche, le coefficient d’allométrie b de la relation poids-longueur variait de 2,04 pour Mugil cephalus à 3,48 Sardinella maderensis avec une moyenne de 2,79 ± 0,03. Le facteur de condition variait en moyenne de 0,66 ± 0,06 pour Sardinella maderensis à 12,22± 0,28 pour Mugil cephalus. En saison des pluies, le coefficient d’allométrie b variait de 2,41 pour Eucinostomus melanopterus à 3,94 pour Sardinella maderensis, avec une moyenne de 3,01 ± 0,05. Le facteur de condition variait de 0,02± 0,002 pour Parachelon grandisquamis à 6,73 ± 0,41 pour Eucinostomus malanopterus. Pour les huit espèces communes, le coefficient d’allométrie b était plus élevé en saison de pluie qu’en saison sèche pour la plupart des espèces (63 %). Conclusion et application des résultats : Ces résultats rapportent des informations relatives à la biologie des poissons rencontrés dans la lagune Mvassa, mais aussi sur l’influence de la saison sur les relations poids-longueur et les coefficients de condition. Dembe Louvinguila et al., 2020 Journal of Animal & Plant Sciences (J.Anim.Plant Sci. ISSN 2071-7024) Vol.44 (1) : 7540-7552 https://doi.org/10.35759/JAnmPlSci.v44-1.1 7541 Seasonal effects on weight-length relationships and condition factors for 16 fish species from the Mvassa Lagoon, Lower Guinea, Republic of the Congo ABSTRACT Objectives: This study was initiated to establish weight-length relationships and condition factors of Ethmalosa fimbriata, Sardinella maderensis, Coptodon guinensis, Oreochromis schwebischi, Neochelon falcipinnis, Mugil cephalus, Parachelon grandisquamis, Eucinostomus melanopterus, Hemichromis elongatus, Pomadasys jubelini, Eleotris daganensis, Bathygobius soporator, Trachinotus teraia, Lutjanus goreensis, Mugil banannensis, et Sarotherodon melanotheron, 16 most abundant species of the Mvassa lagoon in the Republic of Congo. Methodology and results: Fish samples were taken at 9 stations utilizing 8, 10, 20 and 30 mm mesh gillnets. The weight-length relationships were performed using equation P = aLSb and their condition coefficients using equation K = 100*(P/LSb ). A total of 1566 specimens, divided into 5 orders, 8 families, 16 species of which 10 were caught in the dry season, 14 in the rainy season and 8 common species for both seasons were used in this study. The correlation coefficient r 2 was significant for both seasons and ranged from 0.91 for Neochelon falcipinnis and 0.99 for Pomadasys jubelini with an average of 0.97 ± 0.02. In the dry season, the allometry coefficient b of the weight-length relationship ranged from 2.04 for Mugil cephalus to 3.48 Sardinella maderensis with an average of 2.79 ± 0.03. The condition factor ranged on average from 0.66 ± 0.06 for Sardinella maderensis to 12.22 ± 0.28 for Mugil cephalus. In the rainy season, the allometry coefficient b ranged from 2.41 for Eucinostomus melanopterus to 3.940 for Sardinella maderensis, with an average of 3.014 ± 0.05. The condition factor ranged from 0.02 ± 0.002 for Parachelon grandisquamis to 6.73 ± 0.41 for Eucinostomus malanopterus. For the eight common species, the allometry coefficient b was higher in the rainy season than in the dry season for most species (63%). Conclusion and application of the results: These results report information on the biology of the fish encountered in the Mvassa lagoon, but also on the influence of the season on weight- length relationships and condition coefficients

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Taranath, Roopa, Gregory Bourne, Li Zhao, Brian Frederick, Chelsea King, and David Liu. "Regulation of Iron Homeostasis By PTG-300 Improves Disease Parameters in Mouse Models for Beta-Thalassemia and Hereditary Hemochromatosis." Blood 134, Supplement_1 (November 13, 2019): 3540. http://dx.doi.org/10.1182/blood-2019-129309.

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Hepcidin-Ferroportin axis dictates optimal absorption of dietary iron as well as systemic iron levels. This is crucial for providing sufficient iron needed for cellular functions while also preventing iron toxicity. PTG-300 (currently in a Phase 2 clinical study for beta-thalassemia) is a peptide mimetic of natural hepcidin that targets the major iron transporter, ferroportin, and causes its internalization & subsequent degradation. The pharmacodynamic effects of PTG-300 are the reductions in serum iron and transferrin-saturation (TSAT) due to reduced ferroportin expression on cells that store or recycle iron. We chose to demonstrate in two mouse models with iron dysregulation, that our hepcidin mimetics improve disease parameters by correcting dysregulated iron homeostasis. Beta-thalassemia is characterized by an imbalance in alpha-beta globin ratio in erythrocytes due to underlying beta-globin gene mutations. The excess alpha-globin, along with associated heme and iron, form "hemichrome" aggregates that integrate into the membranes of RBCs. The labile iron in these hemichromes generate ROS and are toxic to the cells, causing premature hemolysis of circulating RBCs and reduction in their lifespan. In a mouse model for beta-thalassemia, Hbbth3/+, we investigated the efficacy of a hepcidin mimetic in reducing hemichrome aggregation by limiting iron in the erythroid progenitors, and thereby reducing iron toxicity in RBCs. Subcutaneous injections of 1 mg/kg PN-8772 (analog of PTG-300 which has similar in vitro and in vivo potency) were administered every other day (Q2D) for a period of 4 weeks. At the end of the study, hemichrome aggregates were extracted from RBC membranes, and then analyzed on a TAU gel to quantify the cytoskeleton α-globin band intensities (Casu et al, Blood 2016). Hemichrome aggregates were reduced in groups treated with PN-8772 as compared to untreated controls, with concurrent improvements in hemoglobin and reductions in reticulocytes. Treatment with oral chelator Deferasirox (200 mg/kg; daily) did not show reduction in hemichrome aggregation, while it significantly lowered liver iron-overload. RBCs in Hbbth3/+ mice express aberrant morphologies due to the underlying hemichrome toxicity, similar to the phenotypes expressed in human beta-thalassemia. Chronic treatment with PN-8772 (as described above) also resulted in a significant reduction in aberrant morphologies that are indicative of hemolysis, viz. spherocytes & schistocytes. In a separate study, flow cytometry was used to monitor the survival of RBCs in Hbbth3/+ mice. At the end of 4 weeks of PTG-300 treatment (1 mg/kg, Q2D) the RBCs were marked by an in-life biotinylation method (Schmidt et al, Blood 2013) and subsequently followed over 49 days with continued treatment. There was a significant increase in survival of RBCs as compared to untreated controls. In summary, we demonstrate that by limiting iron in the developing erythroblasts and iron toxicity in RBCs, PTG-300 therapy has the potential to improve the quality of the RBCs and their oxygen carrying capacity, thereby ameliorating anemia. In beta-thalassemia, the clinical presentation includes secondary iron overload in various organs because of hyperabsorption of dietary iron, exacerbated by frequent blood transfusions that are required for management of anemia. Similarly, in hereditary hemochromatosis (HH) there is hyperabsorption of dietary iron leading to primary iron overload. We used a hemochromatosis mouse model (HFE) to demonstrate the effectiveness of PTG-300 therapy in limiting systemic iron toxicity by regulating TSAT and in preventing hyper-iron absorption. The model is characterized by homozygous deletion of HFE with severely low hepcidin levels and consequently very high TSAT (~100%). In this model, a single dose of PTG-300 at 2.5mg/kg reduced TSAT by ~60% at 10-hour post-dose, as compared to untreated controls. Sustained TSAT reduction by chronic treatment will therefore mitigate toxic effects of labile iron. Two weeks of chronic treatment with PTG-300 (2.5 mg/kg, Q2D) effectively prevented iron deposition in the liver. Overall our data suggests that PTG-300 has the potential to be an effective treatment in hemoglobinopathies, like beta-thalassemia, and Hereditary Hemochromatosis, by reducing systemic labile iron toxicity by limiting TSAT, preventing organ iron deposition & improving anemia (in case of thalassemia). Disclosures Taranath: Protagonist Therapeutics: Employment. Bourne:Protagonist Therapeutics: Employment. Zhao:Protagonist Therapeutics: Employment. Frederick:Protagonist Therapeutics: Employment. King:Protagonist Therapeutics: Employment. Liu:Protagonist Therapeutics: Employment.

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Yuan, J., R. Kannan, E. Shinar, EA Rachmilewitz, and PS Low. "Isolation, characterization, and immunoprecipitation studies of immune complexes from membranes of beta-thalassemic erythrocytes." Blood 79, no. 11 (June 1, 1992): 3007–13. http://dx.doi.org/10.1182/blood.v79.11.3007.3007.

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Abstract beta-Thalassemia, a hemoglobinopathy that results in the precipitation of denatured alpha-globin chains on the membrane, is characterized by erythrocytes with significantly reduced lifespans. We have demonstrated previously that hemoglobin denaturation on the membrane can promote clustering of integral membrane proteins, and that this clustering in turn leads to autologous antibody binding, complement fixation, and rapid removal of the cell by macrophages. To evaluate whether this pathway also occurs in beta-thalassemic cells, we have isolated and characterized the immune complexes from the membranes of these cells. We observe that autologous IgG-containing complexes obtained by either immunoprecipitation or simple centrifugation of nondenaturing detergent extracts of beta-thalassemic cell membranes contain globin, band 3, IgG, and complement as major components. Absorption spectra of these complexes demonstrate that the globin is, indeed, mainly in the form of hemichromes. Immunoblotting studies further show that much of the band 3 protein in the aggregates is covalently cross-linked to a dimeric or tetrameric form, consistent with the preference of the autologous IgG for clustered band 3. Although the insoluble aggregates constitute only approximately 1.6% of the total membrane protein, they still contain 27% of the total IgG and 35% of the total complement C3 on the thalassemic cell surface. Because cell surface IgG and complement component C3 are thought to trigger removal of erythrocytes from circulation, the hemichrome-induced clustering of band 3 may contribute to the beta-thalassemic cell's shortened lifespan.

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