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Fulltext Screening of parasitic and IHHNV infections in wild giant freshwater prawn Macrobrachium rosenbergii from Rejang River at Kuching, Sarawak

Kua BC, Choong FC, Hazreen Nita MK, Muhd Faizul H AH, Bhassu S, Imelda RR, et al.

Trop Biomed, 2011 Apr;28(1):85-9.
PMID: 21602773 MyJurnal

A preliminary survey of parasitic and infectious hypodermal and haematopoietic necrosis virus (IHHNV) infections in giant freshwater prawn from the Damak Sea of Rejang River, Kuching, Sarawak was conducted. Symptoms of black spots/patches on the rostrum, carapace, pleopods or telson were observed in most of the 107 samples collected. Parasitic examination revealed sessiline peritrichs such as (Zoothamnium sp.), nematode larvae, gregarine stage and cocoon of leech with prevalences of 1.2%, 1.2%, 5% and 17% respectively. Under histopathological examination, changes like accumulation of hemocytes around hepatopancreatic tubules due to vibriosis, basophilic intranuclear inclusions in the epithelium and E-cell of hepatopancreatic tubules as a result of HPV were seen through the section. No positive infection of IHHNV was detected in 78 samples. As such, the wild giant freshwater prawns in Damak Sea of Rejang River in Kuching are IHHNV-free though infections of parvo-like virus and bacteria were seen in histopathology.

Matched MeSH terms: Parasites/isolation & purification*
Fulltext Malaria parasites of long-tailed macaques in Sarawak, Malaysian Borneo: a novel species and demographic and evolutionary histories

Nada Raja T, Hu TH, Zainudin R, Lee KS, Perkins SL, Singh B

BMC Evol. Biol., 2018 04 10;18(1):49.
PMID: 29636003 DOI: 10.1186/s12862-018-1170-9

BACKGROUND: Non-human primates have long been identified to harbour different species of Plasmodium. Long-tailed macaques (Macaca fascicularis), in particular, are reservoirs for P. knowlesi, P. inui, P. cynomolgi, P. coatneyi and P. fieldi. A previous study conducted in Sarawak, Malaysian Borneo, however revealed that long-tailed macaques could potentially harbour novel species of Plasmodium based on sequences of small subunit ribosomal RNA and circumsporozoite genes. To further validate this finding, the mitochondrial genome and the apicoplast caseinolytic protease M genes of Plasmodium spp. were sequenced from 43 long-tailed macaque blood samples.
RESULTS: Apart from several named species of malaria parasites, long-tailed macaques were found to be potentially infected with novel species of Plasmodium, namely one we refer to as "P. inui-like." This group of parasites bifurcated into two monophyletic clades indicating the presence of two distinct sub-populations. Further analyses, which relied on the assumption of strict co-phylogeny between hosts and parasites, estimated a population expansion event of between 150,000 to 250,000 years before present of one of these sub-populations that preceded that of the expansion of P. knowlesi. Furthermore, both sub-populations were found to have diverged from a common ancestor of P. inui approximately 1.5 million years ago. In addition, the phylogenetic analyses also demonstrated that long-tailed macaques are new hosts for P. simiovale.
CONCLUSIONS: Malaria infections of long-tailed macaques of Sarawak, Malaysian Borneo are complex and include a novel species of Plasmodium that is phylogenetically distinct from P. inui. These macaques are new natural hosts of P. simiovale, a species previously described only in toque monkeys (Macaca sinica) in Sri Lanka. The results suggest that ecological factors could affect the evolution of malaria parasites.

Matched MeSH terms: Parasites/genetics*
The return of chloroquine-sensitive Plasmodium falciparum parasites in Jazan region, southwestern Saudi Arabia over a decade after the adoption of artemisinin-based combination therapy: analysis of genetic mutations in the pfcrt gene

Madkhali AM, Abdulhaq AA, Atroosh WM, Ghzwani AH, Zain KA, Ghailan KY, et al.

Parasitol Res, 2021 Nov;120(11):3771-3781.
PMID: 34561749 DOI: 10.1007/s00436-021-07323-4

This study investigated the polymorphism in the P. falciparum chloroquine resistance transporter (pfcrt) gene 11 years after chloroquine (CQ) cessation in Jazan region, southwestern Saudi Arabia. Two hundred and thirty-five P. falciparum isolates were amplified to detect mutations in the pfcrt gene. The pfcrt 76 T molecular marker for CQ resistance was detected in 66.4% (156/235) of the isolates, while the K76 CQ-sensitive wild type was detected in 33.6%. The pfcrt 74I and pfcrt 75E point mutations were each found to be present in 56.2% of isolates, while only four isolates (1.7%) were found to carry the pfcrt 72S mutation. Moreover, four pfcrt haplotypes were identified as follows: the CVIET triple-allele (56.2%), SVMET double-allele (1.7%) and CVMNT single-allele (8.5%) mutant haplotypes and the CVMNK wild haplotype (33.6%). The analysis also revealed significant associations between the prevalence of mutant pfcrt alleles and haplotypes and the age group, governorate and nationality of the patients as well as the parasitaemia level (p

Matched MeSH terms: Parasites*
Fulltext Diagnostic accuracy and limit of detection of ten malaria parasite lactate dehydrogenase-based rapid tests for Plasmodium knowlesi and P. falciparum

Tan AF, Sakam SSB, Rajahram GS, William T, Abd Rachman Isnadi MF, Daim S, et al.

Front Cell Infect Microbiol, 2022;12:1023219.
PMID: 36325471 DOI: 10.3389/fcimb.2022.1023219

BACKGROUND: Plasmodium knowlesi causes zoonotic malaria across Southeast Asia. First-line diagnostic microscopy cannot reliably differentiate P. knowlesi from other human malaria species. Rapid diagnostic tests (RDTs) designed for P. falciparum and P. vivax are used routinely in P. knowlesi co-endemic areas despite potential cross-reactivity for species-specific antibody targets.
METHODS: Ten RDTs were evaluated: nine to detect clinical P. knowlesi infections from Malaysia, and nine assessing limit of detection (LoD) for P. knowlesi (PkA1-H.1) and P. falciparum (Pf3D7) cultures. Targets included Plasmodium-genus parasite lactate dehydrogenase (pan-pLDH) and P. vivax (Pv)-pLDH.
RESULTS: Samples were collected prior to antimalarial treatment from 127 patients with microscopy-positive PCR-confirmed P. knowlesi mono-infections. Median parasitaemia was 788/µL (IQR 247-5,565/µL). Pan-pLDH sensitivities ranged from 50.6% (95% CI 39.6-61.5) (SD BIOLINE) to 87.0% (95% CI 75.1-94.6) (First Response® and CareStart™ PAN) compared to reference PCR. Pv-pLDH RDTs detected P. knowlesi with up to 92.0% (95% CI 84.3-96.7%) sensitivity (Biocredit™). For parasite counts ≥200/µL, pan-pLDH (Standard Q) and Pv-pLDH RDTs exceeded 95% sensitivity. Specificity of RDTs against 26 PCR-confirmed negative controls was 100%. Sensitivity of six highest performing RDTs were not significantly different when comparing samples taken before and after (median 3 hours) antimalarial treatment. Parasite ring stages were present in 30% of pre-treatment samples, with ring stage proportions (mean 1.9%) demonstrating inverse correlation with test positivity of Biocredit™ and two CareStart™ RDTs.For cultured P. knowlesi, CareStart™ PAN demonstrated the lowest LoD at 25 parasites/µL; LoDs of other pan-pLDH ranged from 98 to >2000 parasites/µL. Pv-pLDH LoD for P. knowlesi was 49 parasites/µL. No false-positive results were observed in either P. falciparum-pLDH or histidine-rich-protein-2 channels.
CONCLUSION: Selected RDTs demonstrate sufficient performance for detection of major human malaria species including P. knowlesi in co-endemic areas where microscopy is not available, particularly for higher parasite counts, although cannot reliably differentiate among non-falciparum malaria.

Matched MeSH terms: Parasites*
Parasitic coinfections among selected smallholder goat flocks in Malaysia

Paul BT, Jesse FAA, Kamaludeen J, Chung ELT, Mat Isa K, Azhar NA, et al.

Trop Biomed, 2023 Dec 01;40(4):444-452.
PMID: 38308832 DOI: 10.47665/tb.40.4.010

This paper describes the occurrence of multiple parasitic infection with special reference to emerging haemotropic Mycoplasma ovis. A cross-sectional survey of four selected goat flocks was conducted to collect samples and management information. Blood samples were processed using microhaematocrit centrifugation to determine the packed cell volume (PCV). Detection and morphological identification of blood protozoa and haemotropic Mycoplasma ovis from Giemsa-stained smears were done microscopically. M. ovis infection was classified mild (1-29% infected cells), moderate (30-59% infected cells), or severe (above 60% infected cells). Faecal floatation and McMaster faecal egg count were used to detect and classify strongyle infections as negative (no eggs/oocysts), light (< 500 epg), Moderate (500 - 1000 epg), or severe (>1000 epg) and coccidia infection as light (<1800 opg), moderate (1800 - 6000 opg), or severe (>6000 opg). There were 149 goats with blood protozoa (57.98%; 95% CI: 51.87 - 63.85) and 204 goats with GI parasites (79.38%; 95% CI: 74.02 - 83.87) involved in single (15.8%; 95% CI: 11.7 - 21.0) or multiple (84.2%; 95% CI: 79.0 - 88.3) infections. The risk of Strongyles increases by 2.49 (95% CI: 1.24 - 4.99) in females versus males and 6.79 (95% CI: 3.25 - 14.18, p =0.000) in adults versus young. The risk of Eimeria species increases by 7.32 (95% CI: 3.45 - 15.50, p =0.000) in adults versus young, while M. ovis coinfection risk increases by 4.51 (95% CI: 1.40 - 14.50, p =0.000) in female versus males. Thin animals had a significantly higher (p<0.05) mean burden of Strongyle (1370.37 ± 345.49) and Eimeria (1594.12 ± 695.26) than the moderate and fat goats. The PCV was negatively associated with mean faecal egg count (FEC) (p<0.05) such that a lower PCV was recorded in animals with a higher Strongyle epg output. A severe burden of M. ovis was accompanied by an increased nematode FEC and decreased haematocrit (p<0.05). Coinfections of Strongyles, or Eimeria species involving M. ovis were associated with a higher parasitaemia compared with single infections (p<0.05). This study highlights the importance of M. ovis and Strongyle or Eimeria species coinfections among goat flocks and provides valuable data for developing and implementing an integrated herd health management program for parasite control among low-input smallholder flocks.

Matched MeSH terms: Parasite Egg Count/veterinary; Parasites*
Fulltext Antiparasitic potential of Nephrolepis biserrata methanol extract against the parasitic leech Zeylanicobdella arugamensis (Hirudinea) and LC-QTOF analysis

Shah MD, Venmathi Maran BA, Haron FK, Ransangan J, Ching FF, Shaleh SRM, et al.

Sci Rep, 2020 12 16;10(1):22091.
PMID: 33328532 DOI: 10.1038/s41598-020-79094-4

Marine leech Zeylanicobdella arugamensis (Piscicolidae), an economically important parasite is infesting predominantly cultured groupers, hybrid groupers and other fish in Southeast Asian countries. In this study, we tested the anti-parasitic potential of a medicinal plant Nephrolepis biserrata found in Sabah, East Malaysia against Z. arugamensis. Various concentrations of methanol extracts of the plant were tested experimentally against Z. arugamensis and disinfestation of the leech from its primary host hybrid groupers. The composition of methanol extract of N. biserrata was determined through LC-QTOF analysis. The significant anti-parasitic activity of 100% mortality of leeches was observed with the exposure of N. biserrata extracts. The average time to kill the leeches at concentrations of 25, 50 and 100 mg/ml was 25.11 ± 3.26, 11.91 ± 0.99, and 4.88 ± 0.50 min., respectively. Further, at various low concentrations of N. biserrata 2.5, 5 and 10 mg/ml, hybrid groupers were disinfested in an average time of 108.33 ± 12.65, 65.83 ± 9.70 and 29.16 ± 5.85 min., respectively. The tandem mass spectrometry data from LC-QTOF indicated some hits on useful bioactive compounds such as terpenoids (ivalin, isovelleral, brassinolide, and eschscholtzxanthin), flavonoids (alnustin, kaempferol 7,4'-dimethyl ether, and pachypodol), phenolics (piscidic acid, chlorogenic acid, and ankorine), and aromatic (3-hydroxycoumarin). Thus N. biserrata can act as a potential biocontrol agent.

Matched MeSH terms: Parasites/drug effects*; Parasites/pathogenicity
A novel nano-anti-malarial induces redox damage and elicits cytokine response to the parasite

Das S, Tripathy S, Pramanik P, Saha B, Roy S

Cytokine, 2021 08;144:155555.
PMID: 33992538 DOI: 10.1016/j.cyto.2021.155555

Emergence and spread of resistant parasites to the newest chemotherapeutic anti-malarial agents are the biggest challenges against malaria control programs. Therefore, developing a novel effective treatment to reduce the overgrowing burden of multidrug resistant malaria is a pressing need. Herein, we have developed a biocompatible and biodegradable, non-toxic chitosan-tripolyphosphate-chloroquine (CS-TPP CQ) nanoparticle. CS-TPP CQ nanoparticles effectively kill the parasite through redox generation and induction of the pro- and anti-inflammatory cytokines in both sensitive and resistant parasite in vitro. The in vitro observations showed a strong inhibitory effect (p

Matched MeSH terms: Parasites/drug effects*; Parasites/metabolism
Fulltext Diagnosis of an imported Plasmodium ovale wallikeri infection in Malaysia

Liew JW, Mahmud R, Tan LH, Lau YL

Malar J, 2016;15:8.
PMID: 26738724 DOI: 10.1186/s12936-015-1070-z

Plasmodium ovale is rare and not exactly known to be autochthonous in Malaysia. There are two distinct forms of the parasite, namely P. ovale curtisi (classic form) and P. ovale wallikeri (variant form). Here, the first sequence confirmed case of an imported P. ovale wallikeri infection in Malaysia is presented. Microscopy found Plasmodium parasites with morphology similar to P. ovale or Plasmodium vivax in the blood films. Further confirmation using polymerase chain reaction (PCR) targeting the small-subunit rRNA gene of the parasite was unsuccessful. Genus-specific PCR was then performed and the product was sequenced and analysed. Sequence analyses confirmed the aetiological agent as P. ovale wallikeri. New species-specific primers (rOVA1v and rOVA2v) were employed and P. ovale wallikeri was finally confirmed. The findings highlight the need to look out for imported malaria infections in Malaysia and the importance of a constantly updated and validated diagnostic technique.

Matched MeSH terms: Parasites
Complete mitochondrial genome of Angiostrongylus malaysiensis lungworm and molecular phylogeny of Metastrongyloid nematodes

Yong HS, Song SL, Eamsobhana P, Lim PE

Acta Trop, 2016 May 17;161:33-40.
PMID: 27207134 DOI: 10.1016/j.actatropica.2016.05.002

Angiostrongylus malaysiensis is a nematode parasite of various rat species. When first documented in Malaysia, it was referred to as A. cantonensis. Unlike A. cantonensis, the complete mitochondrial genome of A. malaysiensis has not been documented. We report here its complete mitogenome, its differentiation from A. cantonensis, and the phylogenetic relationships with its congeners and other Metastrongyloid taxa. The whole mitogenome of A. malaysiensis had a total length of 13,516bp, comprising 36 genes (12 PCGs, 2 rRNA and 22 tRNA genes) and a control region. It is longer than that of A. cantonensis (13,509bp). Its control region had a long poly T-stretch of 12bp which was not present in A. cantonensis. A. malaysiensis and A. cantonensis had identical start codon for the 12 PCGs, but four PCGs (atp6, cob, nad2, nad6) had different stop codon. The cloverleaf structure for the 22 tRNAs was similar in A. malaysiensis and A. cantonensis except the TΨC-arm was absent in trnV for A. malaysiensis but present in A. cantonensis. The Angiostrongylus genus was monophyletic, with A. malaysiensis and A. cantonensis forming a distinct lineage from that of A. costaricensis and A. vasorum. The genetic distance between A. malaysiensis and A. cantonensis was p=11.9% based on 12 PCGs, p=9.5% based on 2 rRNA genes, and p=11.6% based on 14 mt-genes. The mitogenome will prove useful for studies on phylogenetics and systematics of Angiostrongylus lungworms and other Metastrongyloid nematodes.

Matched MeSH terms: Parasites
Plasmodium knowlesi - an emerging pathogen

Ahmed MA, Cox-Singh J

ISBT science series, 2015 Apr;10(Suppl 1):134-140.
PMID: 26029250

Ten years have passed since the publication of a large focus of Plasmodium knowlesi infections in the human population. The discovery was made during a molecular investigation of atypical P. malariae cases in the Kapit Health Division, Sarawak, Malaysian Borneo. Patients were more symptomatic with higher parasite counts than expected in P. malariae infections. The investigation found only P. knowlesi DNA present in patient blood samples. Morphological similarity had allowed P. knowlesi to masquerade as P. malariae during routine diagnostic microscopy for malaria. P. knowlesi, a malaria parasite of macaque monkeys, had entered the human population. The subsequent development of P. knowlesi species-specific PCR assays soon demonstrated that the entry was not confined to the Kapit Division but extended across island and mainland Southeast Asia. Relevant clinical descriptions and guidelines for the treatment and management of patents with P. knowlesi malaria were not available. Nor was it clear whether P. knowlesi had undergone a host switch event into the human population or if infections were zoonotic. The outputs of studies on P. knowlesi malaria during the past 10 years will be summarized, highlighting major findings within the context of pathophysiology, virulence, host switch events, treatment, control and importantly malaria elimination.

Matched MeSH terms: Parasites
Fulltext Human infections with Plasmodium knowlesi--zoonotic malaria

Millar SB, Cox-Singh J

Clin Microbiol Infect, 2015 Jul;21(7):640-8.
PMID: 25843504 DOI: 10.1016/j.cmi.2015.03.017

In 2004 a large focus of Plasmodium knowlesi malaria was reported in the human population in Sarawak, Malaysian Borneo. Plasmodium knowlesi, a parasite of the South-East Asian macaques (Macaca fascicularis and Macaca nemestrina), had entered the human population. Plasmodium knowlesi is transmitted by the leucosphyrus group of Anopheline mosquitoes and transmission is largely zoonotic and restricted to the jungle setting. Humans entering jungle transmission sites are at risk. Since 2004, human cases of P. knowlesi have been continuously reported in local communities and in travellers returning from South East Asia. Plasmodium knowlesi is the most common type of indigenous malaria reported in Malaysia. Infections are most often uncomplicated but at least 10% of patients report with severe malaria and 1-2% of cases have a fatal outcome. Parasitaemia is positively associated with the clinical and laboratory markers of severe malaria. The current literature on P. knowlesi, including epidemiology, natural hosts and vectors, pathogenesis, clinical descriptions, treatment and diagnosis, is reviewed. There are many gaps in our understanding of this disease that are highlighted here with suggestions for further research to inform pre-emptive control measures that would be required to prevent a full emergence of this parasite into the human population.

Matched MeSH terms: Parasites
Fulltext First molecular investigation of haemosporidian parasites in Thai bat species

Arnuphapprasert A, Riana E, Ngamprasertwong T, Wangthongchaicharoen M, Soisook P, Thanee S, et al.

Int J Parasitol Parasites Wildl, 2020 Dec;13:51-61.
PMID: 32904325 DOI: 10.1016/j.ijppaw.2020.07.010

Malaria parasites in the phylum Apicomplexa (Order: Haemosporida) infect diverse vertebrates and invertebrate hosts. At least seven genera of haemosporidian parasites have been described to exclusively infect bats. Most of these parasites remain enigmatic with a poorly known host range. Here, we investigated 271 bats belonging to 21 species and seven families from six provinces of Thailand. Overall, 124 out of 271 bats (45.8%) were positive for haemosporidian parasites, while none had Plasmodium, based on microscopic examination of blood smears and PCR amplification. We obtained 19 distinct cytochrome b (cytb) nucleotide haplotypes of Hepatocystis from seven bat species (families: Craseonycteridae, Hipposideridae, Pteropodidae, and Rhinolophidae). Nycteria was found in four bat species (Craseonycteridae, Emballonuridae, Megadermatidae, and Pteropodidae) and Polychromophilus in two species (Emballonuridae, Vespertilionidae). Phylogenetic analysis inferred from cytb sequences placed Hepatocystis into 2 different clades. Most Hepatocystis infections were found in insectivorous bats and clustered together with a sequence from Hipposideros larvatus in Cambodia (in subclade 1a). A single sequence of Hepatocystis obtained from a frugivorous bat, Cynopterus brachyotis, was placed in the same clade with Hepatocystis from the same bat species previously reported in Malaysia (clade 2). Nycteria in these Thai bats were clearly separated from the African isolates previously reported in bats in the family Rhinolophidae. Polychromophilus murinus from Myotis siligorensis was placed in a distinct clade (clade 2) from Polychromophilus melanipherus isolated from Taphozous melanopogon (clade 1). These results confirmed that at least two distinct species of Polychromophilus are found in Thailand. Collectively, Hepatocystis presented no host specificity. Although Megaderma spasma seemed to be infected by only Nycteria, its respective parasite does not show specificity to only a single bat host. Polychromophilus murinus and P. melanipherus seem to infect a narrower host range or are somehow restricted to bats in the families Vespertilionidae and Emballonuridae, respectively.

Matched MeSH terms: Parasites
Fulltext Capsid structure of Leishmania RNA virus 1

Procházková M, Füzik T, Grybchuk D, Falginella F, Podešvová L, Yurchenko V, et al.

J Virol, 2020 Nov 18.
PMID: 33208443 DOI: 10.1128/JVI.01957-20

Leishmania parasites cause a variety of symptoms, including mucocutaneous leishmaniasis, which results in the destruction of the mucous membranes of the nose, mouth, and throat. The species of Leishmania carrying Leishmania RNA virus 1 (LRV1), from the family Totiviridae, are more likely to cause severe disease and are less sensitive to treatment than those that do not contain the virus. Although the importance of LRV1 for the severity of leishmaniasis was discovered a long time ago, the structure of the virus remained unknown. Here, we present a cryo-electron microscopy reconstruction of the virus-like particle of LRV1 determined to a resolution of 3.65 Å. The capsid has icosahedral symmetry and is formed by 120 copies of a capsid protein assembled in asymmetric dimers. RNA genomes of viruses from the family Totiviridae are synthetized, but not capped at the 5' end, by virus RNA-polymerases. To protect viral RNAs from degradation, capsid proteins of totivirus L-A cleave the 5' caps of host mRNAs, creating decoys to overload the cellular RNA quality control system. Capsid proteins of LRV1 form positively charged clefts, which may be the cleavage sites for the 5' cap of Leishmania mRNAs. Capsid proteins of LRV1 contain a putative RNA binding site distinct from that of the related L-A virus. The structure of the LRV1 capsid enables the rational design of compounds targeting the putative de-capping site. Such inhibitors may be developed into a treatment for mucocutaneous leishmaniasis caused by LRV1-positive species of LeishmaniaIMPORTANCE Twelve million people worldwide suffer from leishmaniasis, resulting in more than thirty thousand deaths annually. The disease has several variants that differ in their symptoms. The mucocutaneous form, which leads to disintegration of the nasal septum, lips, and palate, is predominantly caused by Leishmania parasites carrying Leishmania RNA virus 1 (LRV1). Here, we present the structure of the LRV1 capsid determined using cryo-electron microscopy. Capsid proteins of a related totivirus L-A protect viral RNAs from degradation by cleaving the 5' caps of host mRNAs. Capsid proteins of LRV1 may have the same function. We show that the LRV1 capsid contains positively charged clefts that may be sites for the cleavage of mRNAs of Leishmania cells. The structure of the LRV1 capsid enables the rational design of compounds targeting the putative mRNA cleavage site. Such inhibitors may be used as treatments for muco-cutaneous leishmaniasis.

Matched MeSH terms: Parasites
Serological and molecular rapid diagnostic tests for Toxoplasma infection in humans and animals

Khan AH, Noordin R

Eur J Clin Microbiol Infect Dis, 2020 Jan;39(1):19-30.
PMID: 31428897 DOI: 10.1007/s10096-019-03680-2

Infection by Toxoplasma gondii is prevalent worldwide. The parasite can infect a broad spectrum of vertebrate hosts, but infection of fetuses and immunocompromised patients is of particular concern. Easy-to-perform, robust, and highly sensitive and specific methods to detect Toxoplasma infection are important for the treatment and management of patients. Rapid diagnostic methods that do not sacrifice the accuracy of the assay and give reproducible results in a short time are highly desirable. In this context, rapid diagnostic tests (RDTs), especially with point-of-care (POC) features, are promising diagnostic methods in clinical microbiology laboratories, especially in areas with minimal laboratory facilities. More advanced methods using microfluidics and sensor technology will be the future trend. In this review, we discuss serological and molecular-based rapid diagnostic tests for detecting Toxoplasma infection in humans as well as animals.

Matched MeSH terms: Parasites
Fulltext Serum neopterin is elevated in patients infected with Shigella

Singh KK, Wan-Nurfahizul-Izzati W, Ismail A

Gut Pathog, 2010;2(1):9.
PMID: 20727206 DOI: 10.1186/1757-4749-2-9

Neopterin is produced by human macrophages/monocytes when stimulated with interferon-gamma. Production of neopterin is found in serum, cerebrospinal fluid (CSF) and urine of patients with infections by viruses, intracellular bacteria and parasites, autoimmune diseases, malignant tumors and patients in allograft rejection episodes.

Matched MeSH terms: Parasites
Fulltext Synthesis, characterization and biological properties of copper(II) and zinc(II) complexes against blood-stage Plasmodium falciparum

Lai, Jing-Wei, Ng, Chew-Hee, Lim, Yvonne Ai-Lian, Mohd Jamil Maah

Malaysian Journal of Medicine and Health Sciences, 2019;15(102):1-1.
MyJurnal

Introduction: The spread of multidrug-resistant malaria parasite – Plasmodium sp. to commercially available antimalarial drugs, i.e. artemisinin-based combination therapies (ACTs) and chloroquine (CQ), has become a global treat to eliminate malaria. To limit the impact of antimalarial drug resistance, a new potent and affordable alternative is urgently needed. A number of metal-based compounds (metallodrugs) have been found active against Plasmodium falciparum, the species that causes potentially fatal cerebral malaria, as they are ease in ligand grafting of multi-functional groups. Ferroquine (FQ) is one of the metalloantimalarial drugs that is currently undergoing clinical trials. Methods: In this study, a series of ternary copper(II) and zinc(II) complexes – Cu(phen)(edda) 1, Zn(phen)(edda) 2, [Cu(phen)(cdmg)] NO3 3 and [Zn(phen)(c-dmg)]NO3 4 were synthesized and characterized by the following tests: Fourier transformed infrared (FTIR), CHN elemental analysis, UV-Vis spectroscopy, molar conductivity and magnetic susceptibility measurements. Results: In vitro hemolytic and antimalarial assays using SYBR Green I dye were done to determine the biological properties of these complexes. Preliminary biological evaluation demonstrated that all the complexes 1, 2, 3 and 4 exhibit toxicity against the sensitive blood-stage Plasmodium falciparum 3D7 with IC50 in μM range. Conclusion: Thus, metal complex is a potentially viable candidate as antimalarial drug to overcome the emergence of drug resistance.

Matched MeSH terms: Parasites
Community-acquired pneumonia: aetiology, antibiotic resistance and prospects of phage therapy

Sheam MM, Syed SB, Nain Z, Tang SS, Paul DK, Ahmed KR, et al.

J Chemother, 2020 Dec;32(8):395-410.
PMID: 32820711 DOI: 10.1080/1120009X.2020.1807231

Bacteria are the most common aetiological agents of community-acquired pneumonia (CAP) and use a variety of mechanisms to evade the host immune system. With the emerging antibiotic resistance, CAP-causing bacteria have now become resistant to most antibiotics. Consequently, significant morbimortality is attributed to CAP despite their varying rates depending on the clinical setting in which the patients being treated. Therefore, there is a pressing need for a safe and effective alternative or supplement to conventional antibiotics. Bacteriophages could be a ray of hope as they are specific in killing their host bacteria. Several bacteriophages had been identified that can efficiently parasitize bacteria related to CAP infection and have shown a promising protective effect. Thus, bacteriophages have shown immense possibilities against CAP inflicted by multidrug-resistant bacteria. This review provides an overview of common antibiotic-resistant CAP bacteria with a comprehensive summarization of the promising bacteriophage candidates for prospective phage therapy.

Matched MeSH terms: Parasites
Fulltext Diversity and host associations of Myrsidea chewing lice (Phthiraptera: Menoponidae) in the tropical rainforest of Malaysian Borneo

Madrid RS, Sychra O, Benedick S, Edwards DP, Efeykin BD, Fandrem M, et al.

Int J Parasitol Parasites Wildl, 2020 Dec;13:231-247.
PMID: 33294362 DOI: 10.1016/j.ijppaw.2020.10.011

The tropical rainforests of Sundaland are a global biodiversity hotspot increasingly threatened by human activities. While parasitic insects are an important component of the ecosystem, their diversity and parasite-host relations are poorly understood in the tropics. We investigated parasites of passerine birds, the chewing lice of the speciose genus MyrsideaWaterston, 1915 (Phthiraptera: Menoponidae) in a natural rainforest community of Malaysian Borneo. Based on morphology, we registered 10 species of lice from 14 bird species of six different host families. This indicated a high degree of host specificity and that the complexity of the system could be underestimated with the potential for cryptic lineages/species to be present. We tested the species boundaries by combining morphological, genetic and host speciation diversity. The phylogenetic relationships of lice were investigated by analyzing the partial mitochondrial cytochrome oxidase I (COI) and the nuclear elongation factor alpha (EF-1α) genes sequences of the species. This revealed a monophyletic group of Myrsidea lineages from seven hosts of the avian family Pycnonotidae, one host of Timaliidae and one host of Pellorneidae. However, species delimitation methods supported the species boundaries hypothesized by morphological studies and confirmed that four species of Myrsidea are not single host specific. Cophylogenetic analysis by both distance-based test ParaFit and event-based method Jane confirmed overall congruence between the phylogenies of Myrsidea and their hosts. In total we recorded three cospeciation events for 14 host-parasite associations. However only one host-parasite link (M. carmenae and their hosts Terpsiphone affinis and Hypothymis azurea) was significant after the multiple testing correction in ParaFit. Four new species are described: Myrsidea carmenaesp.n. ex Hypothymis azurea and Terpsiphone affinis, Myrsidea franciscaesp.n. ex Rhipidura javanica, Myrsidea ramonisp.n. ex Copsychus malabaricus stricklandii, and Myrsidea victoriaesp.n. ex. Turdinus sepiarius.

Matched MeSH terms: Parasites
Fulltext Data on antiplasmodial and stage-specific inhibitory effects of Aromatic (Ar)-Turmerone against Plasmodium falciparum 3D7

Ali AH, Agustar HK, Hassan NI, Latip J, Embi N, Sidek HM

Data Brief, 2020 Dec;33:106592.
PMID: 33318979 DOI: 10.1016/j.dib.2020.106592

Aromatic (ar)-turmerone is one of the aromatic constituents abundant in turmeric essential oil from Curcuma longa. Ar-turmerone exhibited anti-inflammatory properties. So far, antiplasmodial data for ar-turmerone is still not reported. The data showed the in vitro antiplasmodial effect of ar-turmerone against Plasmodium falciparum 3D7 (chloroquine-sensitive) via Plasmodium lactate dehydrogenase assay (pLDH) and cytotoxic effect against Vero mammalian kidney cells using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) colourimetric assay. Selectivity indexes of ar-turmerone were calculated based on inhibition concentration at 50% of parasite growth (IC50) from MTT and pLDH assays and the effects of ar-turmerone were compared to the antimalarial reference drug chloroquine diphosphate. The inhibitory effect of ar-turmerone at the intraerythrocytic stages of plasmodial lifecycles was evaluated via a stage-dependant susceptibility test. The antiplasmodial and cytotoxic activities of ar-turmerone revealed IC50 values of 46.8 ± 2.4 μM and 820.4 ± 1.5 μM respectively. The selectivity index of ar-turmerone was 17.5. Ar-turmerone suppressed the ring-trophozoite transition stage of the intraerythrocytic life cycle of P. falciparum 3D7.

Matched MeSH terms: Parasites
Fulltext A rare case of Riamet induced prolonged corrected QT interval

Neesha Sundramoorthy, Khaiteri R., Jer Ming Low, Chan Soon Thim Darren

Malaysian Journal of Medicine and Health Sciences, 2019;15(106):70-70.
MyJurnal

Introduction: Artemether and lumefantrine was registered as Riamet in Switzerland in 1999 and is commonly used in Keningau Hospital for managing uncomplicated malaria. Riamet works at the food vacoule of the malarial parasite, where they interfere with the conversion of heme into haemozoin. Case description: We report a case of Riamet induced prolonged corrected QT interval (QTc) in a 37 year old gentleman admitted for severe malaria (hypotension) with normal QTc of 420msc on presentation. Upon starting Riamet, he developed bradycardia and ECG showed sinus bradycardia with prolonged QTc of 551msec and no arrythmias. Echocardiography showed no structural heart abnormalities. All electrolytes were within normal range. He was monitored in cardiac care unit with decision to complete 6 doses of Riamet. Patient was started on Dopamine infusion which maintained his blood pressure and heart rate within normal range. 5 days post Riamet completion, his heart rate improved and dopamine infusion was tapered off and QTc normalized to 407msc. Discussion: The most common mechanism of drugs causing QT inter-val prolongation is by blocking the human ether-à-go-go related gene (hERG) potassium channel. Blockage of the hEGR channel lengthens ventricular re-polarization and duration of ventricular action potential which is reflected in ECG as prolonged QT interval. In the in-vitro whole cell patch clamp study, lumefantrine and its metabolite desbu-tyl-lumefantrine showed a concentration-dependent inhibition of the hERG current. The period of QTc prolongation was 3.5 to 4 days after the last dose of the standard 6 dose regimen. Conclusion: Riamet induced prolonged QTc is a very rare complication. A baseline electrocardiography is therefore imminent for every patient prior to initiation of this medication to avoid cardiac arrythmias.

Matched MeSH terms: Parasites

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