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  1. Fulltext A description of an automorphism of a non-split metacyclic p-group
    Idham Arif Alias
    Pertanika Journal of Science & Technology, 2011;19(1):109-116.
    MyJurnal
    A map on a group is not necessarily an automorphism on the group. In this paper we study the necessary and sufficient conditions for a map on a non-split metacyclic p-group to be an automorphism, where we only consider p as an odd prime number. The metacyclic group can be defined by a presentation and it will be beneficial to have a direct relation between the parameters in the presentation and an automorphism of the group. We consider the action of an automorphism on the generators of the group mentioned. Since any element of a metacyclic group will be mapped to an element of the group by an automorphism, we can conveniently represent the automorphism in a matrix notation. We then use the relations and the regularity of the non-split metacyclic p-group to find conditions on each entry of the matrix in terms of the parameters in its presentation so that such a matrix does indeed represent an automorphism.
    Matched MeSH terms: Trypanosoma cruzi
  2. A MALAYAB BAT TRYPANOSOME RESEMBLING T. CRUZI AND T. VESPERTILIONIS
    DUNN FL
    Med J Malaysia, 1964 Sep;19:34-5.
    PMID: 14240059
    Matched MeSH terms: Trypanosoma*
  3. Trypanosoma cruzi-like parasites in the slow loris (Nycticebus coucang) from Malaysia
    Kuntz RE, Myers BJ, McMurray TS
    Trans Am Microsc Soc, 1970 Apr;89(2):304-7.
    PMID: 5470359
    Matched MeSH terms: Trypanosoma/isolation & purification*
  4. Trypanosoma cyclops n. sp.: a pigmented trypanosome from the Malaysian primates Macaca nemestrina and M. ira
    Weinman D
    Trans R Soc Trop Med Hyg, 1972;66(4):628-36.
    PMID: 4627177
    Matched MeSH terms: Trypanosoma/classification; Trypanosoma/cytology; Trypanosoma/growth & development; Trypanosoma/isolation & purification*
  5. Seasonal prevalence of bovine trypanosomosis in a tsetse-infested zone and a tsetse-free zone of the Amhara Region, north-west Ethiopia
    Cherenet T, Sani RA, Panandam JM, Nadzr S, Speybroeck N, van den Bossche P
    Onderstepoort J Vet Res, 2004 Dec;71(4):307-12.
    PMID: 15732457
    During a period of four consecutive years, trypanosomosis surveys were conducted in a tsetse-infested and tsetse-free area of the Amhara Region of north-west Ethiopia. In each study area randomly selected communal cattle were sampled and their blood was investigated using parasitological diagnostic methods. At the same time the population of biting flies was sampled. The monthly average prevalence of trypanosome infections in cattle did not differ significantly between study areas. In both study areas, the prevalence of trypanosome infections was highest during the long rainy season. Trypanosome infections were mainly due to Trypanosoma vivax and they significantly reduced the average packed cell volume and the body condition of the animals. The monthly prevalence of infection was correlated with the density of biting flies, such as Tabanidae and Stomoxys spp., in the preceding month suggesting an important role of mechanical transmission in the epidemiology of trypanosomosis in both areas.
    Matched MeSH terms: Trypanosoma brucei brucei/isolation & purification; Trypanosoma congolense/isolation & purification; Trypanosoma vivax/isolation & purification
  6. Malaysian primate trypanosomes: intra-cytoplasmic pigment
    Weinman D
    Southeast Asian J. Trop. Med. Public Health, 1971 Mar;2(1):87.
    PMID: 5000126
    Matched MeSH terms: Trypanosoma/isolation & purification*
  7. Activity of extracts and naphthoquinones from Kigelia pinnata against Trypanosoma brucei brucei and Trypanosoma brucei rhodesiense
    Moideen SV, Houghton PJ, Rock P, Croft SL, Aboagye-Nyame F
    Planta Med, 1999 Aug;65(6):536-40.
    PMID: 10483374
    Dichloromethane extracts of the root bark and stem bark of Kigelia pinnata collected from Zimbabwe exhibited antitrypanosomal activity against Trypanosoma brucei brucei in vitro. Activity-guided fractionation led to the isolation of four naphthoquinones from both the root and stem bark of the plant. The compounds were identified as 2-(1-hydroxyethyl)-naphtho[2,3-b]furan-4,9-quinone (1), isopinnatal (2), kigelinol (3), and isokigelinol (4). Subsequently, the compounds were assessed for antitrypanosomal activity against T. brucei brucei and T. brucei rhodesiense bloodstream form trypomastigotes in vitro. Compound 1 with a furanonaphthoquinone structure was found to possess pronounced activity against both parasites with IC50 values of 0.12 and 0.045 microM, respectively, although it was less active than the standard drug pentamidine. Compounds 2, 3, and 4 also exhibited activity against the parasites, although to a lesser extent. The activities of the compounds were further assessed by comparison with the cytotoxic activities obtained against KB cell lines.
    Matched MeSH terms: Trypanosoma brucei brucei/drug effects*; Trypanosoma brucei brucei/isolation & purification; Trypanosoma brucei rhodesiense/drug effects*
  8. A comparative longitudinal study of bovine trypanosomiasis in tsetse-free and tsetse-infested zones of the Amhara Region, northwest Ethiopia
    Cherenet T, Sani RA, Speybroeck N, Panandam JM, Nadzr S, Van den Bossche P
    Vet Parasitol, 2006 Sep 10;140(3-4):251-8.
    PMID: 16675127
    A study was conducted to determine the incidence of trypanosome infections in cattle in tsetse-free and tsetse-infested zones of the Amhara Region of northwest Ethiopia. A total of six sentinel herds were established and the cattle observed during a period of 8 consecutive months. The prevalence of seropositive cattle was high in both the tsetse-free and tsetse-infested zones. The average monthly incidence of trypanosome infection, determined using molecular diagnostic tools, was 20.9% and 25.7% in the tsetse-free and the tsetse-infested zones, respectively. In the tsetse-free, Trypanosoma vivax was responsible for 90.9% of the cattle trypanosome infections. In the tsetse-infested zone, Trypanosoma congolense and T. vivax contributed almost equally to the trypanosome infections in cattle. Trypanosome infection, regardless of species, resulted in anaemia as evidenced by a significant decrease in the packed cell volume of the infected animal. The outcome of this longitudinal study suggests that control of trypanosomiasis in the Amhara Region cannot be achieved by tsetse control alone. Supplemental measures to include drug therapy and biting fly control are discussed.
    Matched MeSH terms: Trypanosoma congolense/immunology; Trypanosoma congolense/isolation & purification; Trypanosoma vivax/immunology; Trypanosoma vivax/isolation & purification
  9. Fulltext Targeted Isolation of Anti-Trypanosomal Naphthofuran-Quinone Compounds from the Mangrove Plant Avicennia lanata
    Mazlan NW, Clements C, Edrada-Ebel R
    Mar Drugs, 2020 Dec 21;18(12).
    PMID: 33371387 DOI: 10.3390/md18120661
    The discovery of new secondary metabolites from natural origins has become more challenging in natural products research. Different approaches have been applied to target the isolation of new bioactive metabolites from plant extracts. In this study, bioactive natural products were isolated from the crude organic extract of the mangrove plant Avicennia lanata collected from the east coast of Peninsular Malaysia in the Setiu Wetlands, Terengganu, using HRESI-LCMS-based metabolomics-guided isolation and fractionation. Isolation work on the crude extract A. lanata used high-throughput chromatographic techniques to give two new naphthofuranquinone derivatives, hydroxyavicenol C (1) and glycosemiquinone (2), along with the known compounds avicenol C (3), avicequinone C (4), glycoquinone (5), taraxerone (6), taraxerol (7), β-sitosterol (8) and stigmasterol (9). The elucidation and identification of the targeted bioactive compounds used 1D and 2D-NMR and mass spectrometry. Except for 6-9, all isolated naphthoquinone compounds (1-5) from the mangrove plant A. lanata showed significant anti-trypanosomal activity on Trypanosoma brucei brucei with MIC values of 3.12-12.5 μM. Preliminary cytotoxicity screening against normal prostate cells (PNT2A) was also performed. All compounds exhibited low cytotoxicity, with compounds 3 and 4 showing moderate cytotoxicity of 78.3% and 68.6% of the control values at 100 μg/mL, respectively.
    Matched MeSH terms: Trypanosoma brucei brucei/drug effects*; Trypanosoma brucei brucei/physiology
  10. Trypanosuppressive effects of Kolaviron may be associated with down regulation of Trypanothione reductase in Trypanosoma congolense infection
    Timothy MR, Ibrahim YKE, Muhammad A, Chechet GD, Aimola IA, Mamman M
    Trop Biomed, 2021 Mar 01;38(1):94-101.
    PMID: 33797530 DOI: 10.47665/tb.38.1.016
    Trypanothione reductase is a key enzyme that upholds the redox balance in hemoflagellate protozoan parasites such as T. congolense. This study aims at unraveling the potency of Kolaviron against trypanothione reductase in T. congolense infection using Chrysin as standard. The experiment was performed using three different approaches; in silico, in vitro and in vivo. Kolaviron and Chrysin were docked against trypanothione reductase, revealing binding energies (-9.3 and -9.0 kcal/mol) and Ki of 0.211μM and 0.151μM at the active site of trypanothione reductase as evident from the observed strong hydrophobic/hydrogen bond interactions. Parasitized blood was used for parasite isolation and trypanothione reductase activity assay using standard protocol. Real-time PCR (qPCR) assay was implored to monitor expression of trypanothione reductase using primers targeting the 177-bp repeat satellite DNA in T. congolense with SYBR Green to monitor product accumulation. Kolaviron showed IC50 values of 2.64μg/ml with % inhibition of 66.78 compared with Chrysin with IC50 values of 1.86μg/ml and % inhibition of 53.80. In vivo studies following the administration of these compounds orally after 7 days post inoculation resulted in % inhibition of Chrysin (57.67) and Kolaviron (46.90). Equally, Kolaviron relative to Chrysin down regulated the expression trypanothione reductase gene by 1.352 as compared to 3.530 of the infected group, in clear agreement with the earlier inhibition observed at the fine type level. Overall, the findings may have unraveled the Kolaviron potency against Trypanosoma congolense infection in rats.
    Matched MeSH terms: Trypanosoma congolense/drug effects*; Trypanosoma congolense/enzymology
  11. ent-Dioncophylleine A and related dehydrogenated naphthylisoquinoline alkaloids, the first Asian dioncophyllaceae-type alkaloids, from the "new"plant species Ancistrocladus benomensis
    Bringmann G, Dreyer M, Kopff H, Rischer H, Wohlfarth M, Hadi HA, et al.
    J Nat Prod, 2005 May;68(5):686-90.
    PMID: 15921410
    Three new fully dehydrogenated naphthylisoquinoline alkaloids, the 7,1'-coupled ent-dioncophylleine A (3a), the likewise 7,1'-coupled 5'-O-demethyl-ent-dioncophylleine A (4), and the 7,8'-linked dioncophylleine D (5), have been isolated from the leaves of the recently described Malaysian highland liana Ancistrocladusbenomensis. All of them lack an oxygen function at C-6; this so-called Dioncophyllaceae-type structural subclass had previously been found only in naphthylisoquinoline alkaloids from West and Central African plants. Moreover, compounds 3a and 4 are the first fully dehydrogenated, i.e., only axially chiral, naphthylisoquinoline alkaloids of this type that are optically active; compound 5, by contrast, is fully racemic, due to its configurationally unstable biaryl axis. The structural elucidation was achieved by spectroscopic and chiroptical methods. Biological activities of these alkaloids against different protozoan parasites are described.
    Matched MeSH terms: Trypanosoma cruzi/drug effects; Trypanosoma brucei rhodesiense/drug effects
  12. Development of resazurin-based assay in 384-well format for high throughput whole cell screening of Trypanosoma brucei rhodesiense strain STIB 900 for the identification of potential anti-trypanosomal agents
    Lim KT, Zahari Z, Amanah A, Zainuddin Z, Adenan MI
    Exp Parasitol, 2016 Mar;162:49-56.
    PMID: 26772786 DOI: 10.1016/j.exppara.2016.01.002
    To accelerate the discovery of novel leads for the treatment of Human African Trypanosomiasis (HAT), it is necessary to have a simple, robust and cost-effective assay to identify positive hits by high throughput whole cell screening. Most of the fluorescence assay was made in black plate however in this study the HTS assay developed in 384-well format using clear plate and black plate, for comparison. The HTS assay developed is simple, sensitive, reliable and reproducible in both types of plates. Assay robustness and reproducibility were determined under the optimized conditions in 384-well plate was well tolerated in the HTS assay, including percentage of coefficient of variation (% CV) of 4.68% and 4.74% in clear and black 384-well plate, signal-to-background ratio (S/B) of 12.75 in clear 384-well plate and 12.07 in black 384-well plate, Z' factor of 0.79 and 0.82 in clear 384-well plate and black 384-well plate, respectively and final concentration of 0.30% dimethylsulfoxide (DMSO) in both types of plate. Drug sensitivity was found to be comparable to the reported anti-trypanosomal assay in 96-well format. The reproducibility and sensitivity of this assay make it compliant to automated liquid handler use in HTS applications.
    Matched MeSH terms: Trypanosoma
  13. Fulltext Active infection and morphometric study of Trypanosoma evansi among horses in Peninsula Malaysia
    Elshafie EI, Sani RA, Hassan L, Sharma R, Bashir A, Abubakar IA
    Trop Biomed, 2013 Sep;30(3):444-50.
    PMID: 24189674 MyJurnal
    Apart from occasional reports of clinical disease affecting horses, there is no information about Trypanosoma evansi in horses in Peninsula Malaysia. Thus, a cross-sectional study was conducted in eight states in Peninsula Malaysia to determine the active presence of T. evansi in horses. A total of 527 blood samples were obtained and examined by haematocrit centrifugation technique (HCT), Giemsa-stained thin blood smear (GSS), morphometric measurements, polymerase chain reaction (PCR) and cloning of PCR products. The results showed an overall parasitological prevalence of 0.57% (3/527, CI: 1.6-0.19%) with both HCT and GSS. Morphometric study revealed the mean total length of the trypanosomes including the free flagellum was 27.94 ± 2.63 μm. PCR successfully amplified a trypanosome specific 257 bp in 1.14% of samples (6/527, CI: 2.4-0.52%) and was confirmed by nucleotide sequences. The mean packed cell volume (PCV) for the positive cases detected by HCT was lower (23% ± 7.00) compared to the positive cases detected by PCR alone in the state of Terengganu (35% ± 4.73). In conclusion, this study showed T. evansi infection occurred in low frequency in horses in Peninsula Malaysia, and anaemia coincided with parasitaemic animals. PCR is considered as a sensitive diagnostic tool when parasitaemia is undetectable. The slight lengthier mean of parasite and anaemia may indicate a virulent strain of T. evansi circulating throughout the country. Thus, it's highly recommended to shed light on host-parasite relationship for better epidemiological understanding.
    Matched MeSH terms: Trypanosoma/cytology; Trypanosoma/genetics; Trypanosoma/isolation & purification*
  14. Prevalence of hematozoa in some anurans from the Malayan Peninsula
    Sullivan JS, Sullivan JJ
    Southeast Asian J. Trop. Med. Public Health, 1976 Sep;7(3):493-5.
    PMID: 828978
    Matched MeSH terms: Trypanosoma
  15. Possible role of inter-domain salt bridges in oligopeptidase B from Trypanosoma brucei: critical role of Glu172 of non-catalytic β-propeller domain in catalytic activity and Glu490 of catalytic domain in stability of OPB
    Fukumoto J, Ismail NI, Kubo M, Kinoshita K, Inoue M, Yuasa K, et al.
    J. Biochem., 2013 Nov;154(5):465-73.
    PMID: 23946505 DOI: 10.1093/jb/mvt077
    Oligopeptidase B (OPB) is a member of the prolyl oligopeptidase (POP) family of serine proteases. OPB in trypanosomes is an important virulence factor and potential pharmaceutical target. Characteristic structural features of POP family members include lack of a propeptide and presence of a β-propeller domain (PD), although the role of the β-PD has yet to be fully understood. In this work, residues Glu(172), Glu(490), Glu(524) and Arg(689) in Trypanosoma brucei OPB (Tb OPB), which are predicted to form inter-domain salt bridges, were substituted for Gln and Ala, respectively. These mutants were evaluated in terms of catalytic properties and stability. A negative effect on kcat/Km was obtained following mutation of Glu(172) or Arg(689). In contrast, the E490Q mutant exhibited markedly decreased thermal stability, although this mutation had less effect on catalytic properties compared to the E172Q and R689A mutants. Trypsin digestion showed that the boundary regions between the β-PD and catalytic domains (CDs) of the E490Q mutant are unfolded with heat treatment. These results indicated that Glu(490) in the CD plays a role in stabilization of Tb OPB, whereas Glu(172) in the β-PD is critical for the catalytic activity of Tb OPB.
    Matched MeSH terms: Trypanosoma brucei brucei/enzymology*
  16. Triatomines as experimental vectors of trypanosomes of Asian monkeys
    Weinman D, Wallis RC, Cheong WH, Mahadevan S
    Am J Trop Med Hyg, 1978 Mar;27(2 Pt 1):232-7.
    PMID: 417639
    Systematic surveys of the wild macaques of South Asia by blood culture resulted in the discovery that trypanosomiasis is enzootic in the simians of Indonesia, Malaysia, India, and Thailand. The isolates obtained differ in morphology, metabolism, and ability to multiply in arthropods. Following this discovery, interest focused on possible transmissions of these trypanosomiases. Laboratory-reared and wild-caught insects were studied to determine which are satisfactory intermediate hosts and potential natural vectors. Successful results were obtained with insectary-reared reduviids and Indonesian isolates. In Rhodnius prolixus and Triatoma rubrofasciata the Indonesian trypanosomes multiply for periods which can exceed 40 days. The flagellate infections are in the digestive tract, whereas trypanosomes have never been seen in the salivary glands or in the hemolymph. The feces of trypanosome-carrying reduviids are infective, suggesting a stercoreal method of infection of mammals, and infection was produced in experiments in which feeding by the insects was not possible. The relevance of these findings to natural transmission in Indonesia is not known. Experiments with insects and all other trypanosomal isolates have been negative. The natural transmission mechanism(s) of the simian trypanosomiases in South Asia remains an unsolved problem.
    Matched MeSH terms: Trypanosoma/isolation & purification
  17. Molecular Prevalence and Epidemiology of Trypanosoma evansi Among Cattle in Peninsular Malaysia
    Ola-Fadunsin SD, Gimba FI, Abdullah DA, Abdullah FJF, Sani RA
    Acta Parasitol, 2020 Mar;65(1):165-173.
    PMID: 31797192 DOI: 10.2478/s11686-019-00150-9
    BACKGROUND: Animal trypanosomiasis (Surra) caused by Trypanosoma evansi (T. evansi) is known to be one of the important haemoprotozoan parasites that causes great economical loss on animal production due to mortality and loss of condition.

    METHODS: A cross-sectional study was designed to evaluate the prevalence and risk factors associated with T. evansi infection among cattle in Peninsular Malaysia. Polymerase chain reaction (PCR) was employed on 1045 blood samples collected from 43 farms. A well-structured questionnaire was used to collect data on risk factors associated with T. evansi prevalence. The RoTat 1.2 set of primers was used to amplify products of 205 base pair.

    RESULTS: The overall prevalence was found to be 17.9% (187/1045; 95% CI = 15.66-20.31). Trypanosoma evansi was detected among cattle in all the States of Peninsular Malaysia. Breeds of cattle and closeness to waste area, where the risk factors significantly (p 

    Matched MeSH terms: Trypanosoma/genetics*
  18. Molecular detection of Trypanosoma evansi in dogs from India and Southeast Asia
    Nguyen VL, Iatta R, Manoj RRS, Colella V, Bezerra-Santos MA, Mendoza-Roldan JA, et al.
    Acta Trop, 2021 Aug;220:105935.
    PMID: 33930300 DOI: 10.1016/j.actatropica.2021.105935
    Trypanosoma evansi, the causative agent of surra, is a hemoflagellate protozoan mechanically transmitted by hematophagous flies, mainly in tropical and subtropical regions. This protozoan affects several mammalian hosts, including dogs, which are highly susceptible to the infection. To investigate the occurrence of T. evansi in dogs, a total of 672 DNA samples from India (n = 228), Indonesia (n = 57), Malaysia (n = 45), the Philippines (n = 103), Thailand (n = 120), and Vietnam (n = 119) were screened by using species-specific conventional PCR. Of the tested dogs, 10 (1.5%) scored positive to T. evansi. In particular, positive samples were detected in canine blood samples collected from India (n = 4; 1.8%), Indonesia (n = 4; 7%), and Malaysia (n = 2; 4.4%). All tested samples from the Philippines, Thailand and Vietnam were negative. Nucleotide sequence analysis revealed a high variation (i.e. from 0.4% to 6.2%) among the RoTat 1.2 variant surface glycoprotein (vsg) gene. Although the number of sequences included in this analysis is relatively small, this nucleotide variation may indicate the divergence of T. evansi RoTat 1.2 vsg gene among different strains. The high incidence of T. evansi previously reported in cattle and buffaloes in India and Southeast Asia suggests that these animals are the main source of infection to dogs.
    Matched MeSH terms: Trypanosoma/genetics*
  19. Fulltext Epidemiology of blood parasitic infections in the urban rat population in peninsular Malaysia
    Alias SN, Sahimin N, Edah MA, Mohd-Zain SN
    Trop Biomed, 2014 Jun;31(2):230-40.
    PMID: 25134892 MyJurnal
    A total of 719 wild rats were captured from four localities representing the west (Kuala Lumpur), east (Kuantan), north (Georgetown) and south (Malacca) to determine the diversity of blood protozoan from the urban wild rat population in peninsular Malaysia. Five rat species were recovered with Rattus rattus diardii being the most dominant species, followed by Rattus norvegicus, Rattus exulans, Rattus annandalei and Rattus argentiventer. Two blood protozoan species were found infecting the rodent population namely, Plasmodium sp. (42.1%) and Trypanosoma lewisi (25.0%). This study reports the presence of Plasmodium sp. for the first time in the rodent population in Malaysia. Two main intrinsic factors were identified affecting the parasitic infections. Trypanosoma lewisi infections were influenced by host age and sex with infections observed higher in male and juvenile rats meanwhile Plasmodium sp. infections were observed almost similar in both sexes. However, infections were higher in sub-adult rats.
    Matched MeSH terms: Trypanosoma lewisi/isolation & purification*
  20. Fulltext Comparative seroprevalences of bovine trypanosomiasis and anaplasmosis in five states of Malaysia
    Rahman WA, Fong S, Chandrawathani P, Nurulaini R, Zaini CM, Premalaatha B
    Trop Biomed, 2012 Mar;29(1):65-70.
    PMID: 22543604 MyJurnal
    A comparative seroprevalence study on bovine trypanosomiasis and anaplasmosis was conducted. Sera of adult cattle and buffaloes of different breeds from farms from five different states in Malaysia were collected and tested for the presence of Trypanosoma evansi antibodies by CATT and Anaplasma marginale antibodies by c-ELISA. Of the 116 samples, 14.7% tested positive for bovine trypanosomiasis and 77.6% for bovine anaplasmosis.
    Matched MeSH terms: Trypanosoma/immunology
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