MyMedR

Displaying all 6 publications

Abstract:

Sort:

Review of the genus Mansonella Faust, 1929 sensu lato (Nematoda: Onchocercidae), with descriptions of a new subgenus and a new subspecies

Bain O, Mutafchiev Y, Junker K, Guerrero R, Martin C, Lefoulon E, et al.

Zootaxa, 2015;3918(1):151-93.
PMID: 25781087 DOI: 10.11646/zootaxa.3918.2.1

Based on material deposited in museum collections, twelve species within Mansonella sensu lato were examined and their descriptions amended. Based on additional morphological details, the erection of the new monotypic subgenus Filyamagutia Bain & Uni for M. (F.) akitensis (Uni, 1983), and the new combination M. (Pseudolitomosa) musasabi (Yamaguti, 1941) Bain & Uni are proposed. A new subspecies, M. (Tetrapetalonema) atelensis amazonae Bain & Guerrero is described and a key to the seven subgenera of Mansonella is provided. Furthermore, the elevation of Sandnema to full genus rank comprising the two species S. digitatum (Chandler, 1929) n. comb. and S. sunci (Sandground, 1933) n. comb., is proposed. Host and geographic records for the species of Mansonella and Sandnema are included.
Fulltext Serological measures to assess the efficacy of malaria control programme on Ambae Island, Vanuatu

Idris ZM, Chan CW, Mohammed M, Kalkoa M, Taleo G, Junker K, et al.

Parasit Vectors, 2017 Apr 26;10(1):204.
PMID: 28441959 DOI: 10.1186/s13071-017-2139-z

BACKGROUND: Seroepidemiology can provide evidence for temporal changes in malaria transmission and is an important tool to evaluate the effectiveness of control interventions. During the early 2000s, Vanuatu experienced an acute increase in malaria incidence due to a lapse in funding for vector control. After the distribution of subsidised insecticide-treated nets (ITNs) resumed in 2003, malaria incidence decreased in the subsequent years. This study was conducted to find the serological evidence supporting the impact of ITN on exposure to Anopheles vector bites and parasite prevalence.
METHODS: On Ambae Island, blood samples were collected from 231 and 282 individuals in 2003 and 2007, respectively. Parasite prevalence was determined by microscopy. Antibodies to three Plasmodium falciparum (PfSE, PfMSP-119, and PfAMA-1) and three Plasmodium vivax (PvSE, PvMSP-119, and PvAMA-1) antigens, as well as the Anopheles-specific salivary antigen gSG6, were detected by ELISA. Age-specific seroprevalence was analysed using a reverse catalytic modelling approach to estimate seroconversion rates (SCRs).
RESULTS: Parasite rate decreased significantly (P
Fulltext Redescription, molecular characterisation and Wolbachia endosymbionts of Mansonella (Tupainema) dunni (Mullin & Orihel, 1972) (Spirurida: Onchocercidae) from the common treeshrew Tupaia glis Diard & Duvaucel (Mammalia: Scandentia) in Peninsular Malaysia

Mat Udin AS, Uni S, Rodrigues J, Martin C, Junker K, Agatsuma T, et al.

Curr Res Parasitol Vector Borne Dis, 2024;5:100154.
PMID: 38193019 DOI: 10.1016/j.crpvbd.2023.100154

The genus Mansonella Faust, 1929 includes 29 species, mainly parasites of platyrrhine monkeys in South America and anthropoid apes in Africa. In Malaysia, Mansonella (Tupainema) dunni (Mullin & Orihel, 1972) was described from the common treeshrew Tupaia glis Diard & Duvaucel (Scandentia). In a recent classification of the genus Mansonella, seven subgenera were proposed, with M. (Tup.) dunni as a monotypic species in the subgenus Tupainema. In this study, we collected new material of M. (Tup.) dunni from common treeshrews in Peninsular Malaysia and redescribed the morphological features of this species. We found that M. (Tup.) dunni differs from M. (Cutifilaria) perforata Uni et al., 2004 from sika deer Cervus nippon (Cetartiodactyla) in Japan, with regards to morphological features and predilection sites in their respective hosts. Based on multi-locus sequence analyses, we examined the molecular phylogeny of M. (Tup.) dunni and its Wolbachia genotype. Species of the genus Mansonella grouped monophyletically in clade ONC5 and M. (Tup.) dunni was placed in the most derived position within this genus. Mansonella (Tup.) dunni was closely related to M. (M.) ozzardi (Manson, 1897) from humans in Central and South America, and most distant from M. (C.) perforata. The calculated p-distances between the cox1 gene sequences for M. (Tup.) dunni and its congeners were 13.09% for M. (M.) ozzardi and 15.6-16.15% for M. (C.) perforata. The molecular phylogeny of Mansonella spp. thus corroborates their morphological differences. We determined that M. (Tup.) dunni harbours Wolbachia endosymbionts of the supergroup F genotype, in keeping with all other Mansonella species screened to date.
Fulltext Description and molecular characterisation of Pelecitus copsychi Uni, Mat Udin & Martin n. sp. (Nematoda: Onchocercidae) from the white-rumped shama Copsychus malabaricus (Scopoli) (Passeriformes: Muscicapidae) of Pahang, Malaysia

Uni S, Mat Udin AS, Tan PE, Rodrigues J, Martin C, Junker K, et al.

Curr Res Parasitol Vector Borne Dis, 2022;2:100078.
PMID: 36589876 DOI: 10.1016/j.crpvbd.2022.100078

Species of the genus Pelecitus Railliet & Henry, 1910 the most widely distributed avian filariae in Africa and South America. Zoonotic cases in humans were reported in South America. While investigating the filarial fauna of wild animals in Malaysia, we discovered an undescribed filaria from the swollen footpad of the left leg of Copsychus malabaricus (Scopoli) in Pahang, Peninsular Malaysia. Adults of both sexes have a corkscrew-shaped body. Based on comparison of their morphological characteristics (i.e. pre-oesophageal cuticular ring distinct, oesophagus divided, vulva protuberant and situated at the level of anterior half of oesophagus, spicules strongly sclerotized and left spicule with broad blade) with other Pelecitus species, they are here described as Pelecitus copsychi Uni, Mat Udin & Martin n. sp. Multi-locus sequence analyses based on seven genes (12S rDNA, cox1, 18S rDNA, 28S rDNA, MyoHC, rbp1 and hsp70) were performed to determine the phylogenetic position of the new species. The calculated p-distance between the cox1 gene sequences for P. copsychi n. sp. and Pelecitus fulicaeatrae (Diesing, 1861) was 14.1%. Intraspecific genetic variation between two individuals of the new species was 0.4%. In both the Bayesian inference and maximum-likelihood trees, P. copsychi n. sp. was positioned in the second clade of ONC5, containing three genera of the subfamily Dirofilariinae (Foleyella Seurat, 1917, Pelecitus and Loa Stiles, 1905). Immunostaining and molecular analyses remained negative for the presence of Wolbachia endosymbionts. Our findings corroborate the division of the subfamily Dirofilariinae into ONC3 with Dirofilaria Railliet & Henry, 1911 and ONC5 with Pelecitus.
Fulltext Morphological and molecular characteristics of Malayfilaria sofiani Uni, Mat Udin & Takaoka n. g., n. sp. (Nematoda: Filarioidea) from the common treeshrew Tupaia glis Diard & Duvaucel (Mammalia: Scandentia) in Peninsular Malaysia

Uni S, Mat Udin AS, Agatsuma T, Saijuntha W, Junker K, Ramli R, et al.

Parasit Vectors, 2017 Apr 20;10(1):194.
PMID: 28427478 DOI: 10.1186/s13071-017-2105-9

BACKGROUND: The filarial nematodes Wuchereria bancrofti (Cobbold, 1877), Brugia malayi (Brug, 1927) and B. timori Partono, Purnomo, Dennis, Atmosoedjono, Oemijati & Cross, 1977 cause lymphatic diseases in humans in the tropics, while B. pahangi (Buckley & Edeson, 1956) infects carnivores and causes zoonotic diseases in humans in Malaysia. Wuchereria bancrofti, W. kalimantani Palmieri, Pulnomo, Dennis & Marwoto, 1980 and six out of ten Brugia spp. have been described from Australia, Southeast Asia, Sri Lanka and India. However, the origin and evolution of the species in the Wuchereria-Brugia clade remain unclear. While investigating the diversity of filarial parasites in Malaysia, we discovered an undescribed species in the common treeshrew Tupaia glis Diard & Duvaucel (Mammalia: Scandentia).
METHODS: We examined 81 common treeshrews from 14 areas in nine states and the Federal Territory of Peninsular Malaysia for filarial parasites. Once any filariae that were found had been isolated, we examined their morphological characteristics and determined the partial sequences of their mitochondrial cytochrome c oxidase subunit 1 (cox1) and 12S rRNA genes. Polymerase chain reaction (PCR) products of the internal transcribed spacer 1 (ITS1) region were then cloned into the pGEM-T vector, and the recombinant plasmids were used as templates for sequencing.
RESULTS: Malayfilaria sofiani Uni, Mat Udin & Takaoka, n. g., n. sp. is described based on the morphological characteristics of adults and microfilariae found in common treeshrews from Jeram Pasu, Kelantan, Malaysia. The Kimura 2-parameter distance between the cox1 gene sequences of the new species and W. bancrofti was 11.8%. Based on the three gene sequences, the new species forms a monophyletic clade with W. bancrofti and Brugia spp. The adult parasites were found in tissues surrounding the lymph nodes of the neck of common treeshrews.
CONCLUSIONS: The newly described species appears most closely related to Wuchereria spp. and Brugia spp., but differs from these in several morphological characteristics. Molecular analyses based on the cox1 and 12S rRNA genes and the ITS1 region indicated that this species differs from both W. bancrofti and Brugia spp. at the genus level. We thus propose a new genus, Malayfilaria, along with the new species M. sofiani.
Fulltext Description, molecular characteristics and Wolbachia endosymbionts of Onchocerca borneensis Uni, Mat Udin & Takaoka n. sp. (Nematoda: Filarioidea) from the Bornean bearded pig Sus barbatus Müller (Cetartiodactyla: Suidae) of Sarawak, Malaysia

Uni S, Mat Udin AS, Agatsuma T, Junker K, Saijuntha W, Bunchom N, et al.

Parasit Vectors, 2020 Feb 06;13(1):50.
PMID: 32028994 DOI: 10.1186/s13071-020-3907-8

BACKGROUND: The genus Onchocerca Diesing, 1841 includes species of medical importance, such as O. volvulus (Leuckart, 1893), which causes river blindness in the tropics. Recently, zoonotic onchocercosis has been reported in humans worldwide. In Japan, O. dewittei japonica Uni, Bain & Takaoka, 2001 from wild boars is a causative agent for this zoonosis. Many filarioid nematodes are infected with Wolbachia endosymbionts which exhibit various evolutionary relationships with their hosts. While investigating the filarial fauna of Borneo, we discovered an undescribed Onchocerca species in the bearded pig Sus barbatus Müller (Cetartiodactyla: Suidae).
METHODS: We isolated Onchocerca specimens from bearded pigs and examined their morphology. For comparative material, we collected fresh specimens of O. d. dewittei Bain, Ramachandran, Petter & Mak, 1977 from banded pigs (S. scrofa vittatus Boie) in Peninsular Malaysia. Partial sequences of three different genes (two mitochondrial genes, cox1 and 12S rRNA, and one nuclear ITS region) of these filarioids were analysed. By multi-locus sequence analyses based on six genes (16S rDNA, ftsZ, dnaA, coxA, fbpA and gatB) of Wolbachia, we determined the supergroups in the specimens from bearded pigs and those of O. d. dewittei.
RESULTS: Onchocerca borneensis Uni, Mat Udin & Takaoka n. sp. is described on the basis of morphological characteristics and its genetic divergence from congeners. Molecular characteristics of the new species revealed its close evolutionary relationship with O. d. dewittei. Calculated p-distance for the cox1 gene sequences between O. borneensis n. sp. and O. d. dewittei was 5.9%, while that between O. d. dewittei and O. d. japonica was 7.6%. No intraspecific genetic variation was found for the new species. Wolbachia strains identified in the new species and O. d. dewittei belonged to supergroup C and are closely related.
CONCLUSIONS: Our molecular analyses of filarioids from Asian suids indicate that the new species is sister to O. d. dewittei. On the basis of its morphological and molecular characteristics, we propose to elevate O. d. japonica to species level as O. japonica Uni, Bain & Takaoka, 2001. Coevolutionary relationships exist between the Wolbachia strains and their filarial hosts in Borneo and Peninsular Malaysia.