scholarly journals Soil-transmitted helminth infections in free-ranging non-human primates from Cameroon and Gabon

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
C. Sirima ◽  
C. Bizet ◽  
H. Hamou ◽  
B. Červená ◽  
T. Lemarcis ◽  
...  

Abstract Background Zoonotic diseases are a serious threat to both public health and animal conservation. Most non-human primates (NHP) are facing the threat of forest loss and fragmentation and are increasingly living in closer spatial proximity to humans. Humans are infected with soil-transmitted helminths (STH) at a high prevalence, and bidirectional infection with NHP has been observed. The aim of this study was to determine the prevalence, genetic diversity, distribution and presence of co-infections of STH in free-ranging gorillas, chimpanzees and other NHP species, and to determine the potential role of these NHP as reservoir hosts contributing to the environmental sustenance of zoonotic nematode infections in forested areas of Cameroon and Gabon. Methods A total of 315 faecal samples from six species of NHPs were analysed. We performed PCR amplification, sequencing and maximum likelihood analysis of DNA fragments of the internal transcribed spacer 2 (ITS2) nuclear ribosomal DNA to detect the presence and determine the genetic diversity of Oesophagostomum spp., Necator spp. and Trichuris spp., and of targeted DNA fragments of the internal transcribed spacer 1 (ITS1) to detect the presence of Ascaris spp. Results Necator spp. infections were most common in gorillas (35 of 65 individuals), but also present in chimpanzees (100 of 222 individuals) and in one of four samples from greater spot-nosed monkeys. These clustered with previously described type II and III Necator spp. Gorillas were also the most infected NHP with Oesophagostomum (51/65 individuals), followed by chimpanzees (157/222 individuals), mandrills (8/12 samples) and mangabeys (7/12 samples), with O. stephanostomum being the most prevalent species. Oesophagostomum bifurcum was detected in chimpanzees and a red-capped mangabey, and a non-classified Oesophagostomum species was detected in a mandrill and a red-capped mangabey. In addition, Ternidens deminutus was detected in samples from one chimpanzee and three greater spot-nosed monkeys. A significant relative overabundance of co-infections with Necator and Oesophagostomum was observed in chimpanzees and gorillas. Trichuris sp. was detected at low prevalence in a gorilla, a chimpanzee and a greater spot-nosed monkey. No Ascaris was observed in any of the samples analysed. Conclusions Our results on STH prevalence and genetic diversity in NHP from Cameroon and Gabon corroborate those obtained from other wild NHP populations in other African countries. Future research should focus on better identifying, at a molecular level, the species of Necator and Oesophagostomum infecting NHP and determining how human populations may be affected by increased proximity resulting from encroachment into sylvatic STH reservoir habitats. Graphical Abstract

Genome ◽  
1997 ◽  
Vol 40 (5) ◽  
pp. 730-743 ◽  
Author(s):  
Malika L. Ainouche ◽  
Randall J. Bayer

The internal transcribed spacer (ITS) region of nuclear ribosomal DNA from 22 diploid and tetraploid annual Bromus species of section Bromus (Poaceae) and three species belonging to other Bromus sections, Bromus catharticus (section Ceratochloa), Bromus anomalus (section Pnigma), and Bromus sterilis (section Genea), were investigated by PCR amplification and direct sequencing. The length of the ITS-1 region varied from 215 to 218 bp, and that of the ITS-2 region from 215 to 216 bp, in the species analyzed. ITS-1 was more variable and provided more informative sites (49) than ITS-2 (32). No variation was encountered within species. In pairwise comparison among species of section Bromus, sequence divergence ranged from 0.0 to 8.0% for the combined ITS-1 and ITS-2 regions. Parsimony analysis using Avena longiglumis and Hordeum vulgare as outgroups resulted in well-resolved phylogenetic trees and showed that section Bromus is monophyletic according to the species analyzed outside of the section. The analysis clarified the phylogenetic relationships among monogenomic (diploid) species. Introduction of the allotetraploid species did not change the general topology of the trees obtained using only the diploid species. Although some tetraploid–diploid species relationships will have to be clarified with faster evolving markers, the ITS sequences are shown to be useful for assessing evolutionary relationships among closely related Bromus species, as well as for clarifying taxonomic problems in previously controversial cases (e.g., Bromus alopecuros and Bromus caroli–henrici). New hypotheses are proposed concerning the origin of several allotetraploid species. For example, it is shown that the tetraploid Bromus hordeaceus diverged earlier than all other species of section Bromus, excluding the diploid B. caroli–henrici, which is found to be basal in this group. The tetraploid Bromus arenarius, which was considered a hybrid between sections Bromus and Genea, and the tetraploid Bromus adoensis are sister taxa within section Bromus; they belong in a weakly differentiated clade with the diploids Bromus brachystachys, Bromus japonicus, Bromus squarrosus, Bromus arvensis, and Bromus intermedius.Key words: Bromus, allopolyploidy, ITS, ribosomal DNA, phylogeny.


2020 ◽  
Vol 25 (1) ◽  
pp. 1
Author(s):  
Karlia Meitha ◽  
Intan Fatmawati ◽  
Fenny Martha Dwivany ◽  
Agus Sutanto ◽  
Sigit Nur Pratama ◽  
...  

Pisang Kepok (Musa spp. [ABB ’Saba’ subgroup]) has several unique characteristics, such as tolerance to drought and Fusarium Foc (TR4) disease. Currently, the genetic diversity of Pisang Kepok in Indonesia is not well identified, although it is widely cultivated. Information on genetic diversity is essential for developing breeding strategies to achieve efficient cultivar improvement in the future. Aims of this research were to analyze the genetic variation of Pisang Kepok from some islands in Indonesia and to determine the genetic relationship between Pisang Kepok and other accessions banana cultivars based on ITS2 region, as a basis for future research in improving banana quality through molecular breeding. We have conducted the multiple sequence alignment and built the phylogenetic tree analysis using the Bayesian Inference Phylogeny method of one million generations (ngen = 1,000,000). The ITS2 region showed two clade ingroups: first clade consists of banana with B genome (balbisiana), while the second clade consists of banana with only A genome (acuminata). In general, all accessions of Pisang Kepok cultivars were clustered in the B genome of bananas cultivars. In addition, the ITS2 sequences and secondary structures among Pisang Kepok from various regions are identical, suggesting that there was no genetic variation in the ITS2 region of Pisang Kepok from multiple areas in Indonesia.


2021 ◽  
Author(s):  
Danlami Akafyi ◽  
Iliya Shehu Ndams ◽  
Ishaya Haruna Nock ◽  
Gloria Chechet ◽  
Renz Alfons ◽  
...  

Abstract Background: A better understanding of parasite population genetic processes in specific biogeography is needed to support onchocerciasis elimination goals. The genetic diversity of Onchocerca microfilariae was explored by amplifying a fragment of the 16S rRNA gene in the endemic area in Taraba State, Nigeria, Methods: Eight (8) communities were selected including six onchocerciasis endemic communities with records of ivermectin treatment having been annually distributed for 10 to 16 years, and two non-onchocerciasis endemic areas. The participants were 211 from endemic and 110 from non-endemic areas as control. Skin snips were taken from consenting participants by convenience sampling methods using a sterile sclera punch, from males and females residing within the communities for ten years and above or since birth, microfilaria and residual skin snips were preserved in RNALater® in a 1.5 ml micro-centrifuge tube. DNA was extracted from microfilariae recovered and from those in residual skin snip specimens. Polymerase Chain Reaction (PCR) amplification using specific primers for 16S genes was done to detect the identity of Onchocerca species. The amplified products were sequenced and analyzed for species identity. Results: Multiple sequence alignment and phylogenetic analysis results showed distinct diversity of two sample sequences (G49_O.v. Gashaka and Y02_O.v. Yorro) from other samples from the study area and other regions, indicating emergence of a new polymorphic strain of O. volvulus. Report of a preliminary case of emerging zoonosis of O. ochengi infection in human (skin snips) sample (O. ochengi G44) in this study. Conclusions: It is clear there is genetic diversity of Onchocerca species and emerging zoonosis in the study site. We suggest further investigation on the extent and potentials of emerging zoonotic onchocerciasis by O. ochengi, in the light of cattle, Simulium vectors, environmental and humans overlap in the study area.


2011 ◽  
Vol 34 (5) ◽  
pp. 717-726 ◽  
Author(s):  
Yuki Kitani ◽  
Shu Zhu ◽  
Javzan Batkhuu ◽  
Chinbat Sanchir ◽  
Katsuko Komatsu

Planta Medica ◽  
2008 ◽  
Vol 74 (09) ◽  
Author(s):  
YH Kim ◽  
JA Ryuk ◽  
BS Ko ◽  
JW Lee ◽  
SE Oh ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document