Journal Detail Information

1

Cite

Share

Hemoprotozoa and Anaplasma spp. in rodents and shrews of Bangladesh

Islam, S. ; Rahman, M.K. ; Ferdous, J. ; Rahman, M. ; Akter, S. ; Faraque, M.O. ; Chowdhury, M.N.U. ; Hossain, M.A. ; Hassan, M.M. ; Islam, A. ; Islam, A.

Tropical Biomedicine.2020;37(No.4):842-851. doi:https://doi.org/10.47665/tb.37.4.842

Hemoprotozoans are important pathogens of animals and humans, among which some species have zoonotic significance. The prevalence of different hemoprotozoa and Anaplasma spp. in larger mammals have been reported from different regions of the world. But, very few studies have been conducted to estimate the prevalence of hemoprotozoa in rodents and shrews of South-East Asia. The study assessed the prevalence of hemoprotozoa and Anaplasma spp. in rodents and shrews of Bangladesh. Blood samples (n=451) were collected from rodents and shrews between June 2011 and June 2013 and July-December 2015 from 4 land gradients of Bangladesh. Giemsa-stained blood smears revealed that 13% of animals were harboring hemoprotozoa (4.7% Babesia spp., 0.67% Plasmodium spp.), and Anaplasma spp. (7.5%). The study may serve as a guide for future hemoparasitic research of rodents and shrews.

2

Cite

Share

Clone, expression and plasminogen binding property of three fructose-1,6-bisphosphate aldolases from Clonorchis sinensis

Li, S. ; Lu, B.P. ; Feng, J. ; Zhou, J.J. ; Xie, Z.Z. ; Liang, C. ; Li, X.R. ; Huang, Y. ; Yu, X.B.

Tropical Biomedicine.2020;37(No.4):852-863. doi:https://doi.org/10.47665/tb.37.4.852

Fructose-1,6-bisphosphate aldolase (FbA), a well characterized glycometabolism enzyme, has been found to participate in other important processes besides the classic catalysis. To understand the important functions of three fructose-1,6-bisphosphate aldolases from Clonorchis sinensis (CsFbAs, CsFbA-1/2/3) in host-parasite interplay, the open reading frames of CsFbAs were cloned into pET30a (+) vector and the resulting recombinant plasmids were transformed into Escherichia coli BL21 (DE3) for expression of the proteins. Purified recombinant CsFbAs proteins (rCsFbAs) were approximately 45.0 kDa on 12% SDS-PAGE and could be probed with each rat anti-rCsFbAs sera by western blotting analysis. ELISA and ligand blot overlay indicated that rCsFbAs of 45.0 kDa as well as native CsFbAs of 39.5 kDa from total worm extracts and excretory-secretory products of Clonorchis sinensis (CsESPs) could bind to human plasminogen, and the binding could be efficiently inhibited by lysine analog ε-aminocaproic acid. Our results suggested that as both the components of CsESPs and the plasminogen binding proteins, three CsFbAs might be involved in preventing the formation of the blood clot so that Clonorchis sinensis could acquire enough nutrients from host tissue for their successful survival and colonization in the host. Our work will provide us with new information about the biological function of three CsFbAs and their roles in hostparasite interplay

3

Cite

Share

Isolation of Beauveria bassiana Pr-11 from Andean orthopterans and its effectiveness against Chagas disease vectors in Peru

Castellanos-Sá ; nchez, P. ; Falconi-Agapito, F. ; Pariona, N. ; Paredes-Esquivel, C.

Tropical Biomedicine.2020;37(No.4):864-870. doi:https://doi.org/10.47665/tb.37.4.864

Chagas disease is endemic to the Americas and is transmitted by blood-feeding kissing bugs. We evaluated the insecticidal potential of a fungus (Beauveria bassiana strain Pr-11) against Triatoma infestans, an important vector in South America. This fungal species was isolated from a locust (Schistocerca piceifrons) that inhabits the Central Andes region of Peru. Ten days post inoculation, this strain induced high insect mortality (97%) at low fungal concentrations (2 × 107 conidia/ml) at 70% relative humidity. The Pr-11 strain outperformed reference strain CCBLE-216 B. bassiana, provided by the Peruvian Ministry of Agriculture. Our results are consistent with previous reports on the virulence of this fungal strain against other insect pests. This is the first study to evaluate an orthopteran-isolated B. bassiana to control Chagas disease vectors. We conclude that strain Beauveria bassiana Pr-11 is effective against Triatoma infestans, resulting in a promising tool to control Chagas disease in Peru and may be used in integrated vector control programs.

4

Cite

Share

Evaluation of the inhibitory effects of drugs on the growth of Babesia gibsoni using relative quantification real-time PCR

He, W.H. ; Feng, X.X. ; Wu, X. ; Zhai, X.H. ; Li, Y.Y. ; Zhang, B. ; Yao D.W.

Tropical Biomedicine.2020;37(No.4):871-876. doi:https://doi.org/10.47665/tb.37.4.871

To evaluate the inhibitory effects of drugs on the growth of Babesia gibsoni, relative quantification real-time PCR method was developed in this study. The 18S rRNA gene was used as a target gene for the 2–ΔΔCt method analysis. Additionally, chicken RNA was added to the parasitized blood before total RNA extraction. The chicken β-actin gene was selected as an internal control gene for the 2–ΔΔCt method analysis. The 100 µL parasitized blood samples with different percentages of parasitized erythrocytes (PPEs) (3%, 1.5%, 0.75%, 0.375% and 0.1875%) were prepared for relative quantification of B. gibsoni. Regression analysis results revealed significant linear relationships between the relative quantification value and parasitemia. 18S rRNA gene expression was significantly decreased after treatment with diminazene aceturate and artesunate in vitro drug sensitivity test. This result suggested that this relative quantification real-time PCR method can be used to evaluate the effects of drug inhibition.

5

Cite

Share

The dichotomy of the systemic and local cytokine responses of mucosal leishmaniasis patients in Sudan: A pilot study

Abdelhaleem, A.A. ; Elamin, E.M. ; Elhassan, A.M. ; Nail, A.M. ; Abdullah, N.E. ; Mukhtar, M.M.

Tropical Biomedicine.2020;37(No.4):877-883. doi:https://doi.org/10.47665/tb.37.4.877

Sudanese mucosal leishmaniasis (ML) is a rare clinical form of leishmaniasis and characterized by persistent ulcer of the oral and/or the nasal mucous membranes caused by Leishmania donovani. No data is available about the systemic and local immune responses in mucosal leishmaniasis. This study aimed to measure the systemic and the local cytokines responses of Sudanese ML patients compared to cured cutaneous leishmaniasis patients (Leishmanin skin test positive, LST+ve) and unexposed healthy controls (Leishmanin skin test negative, LST-ve). Six parasitological confirmed ML patients, 7 LST+ve, and 6 LST-ve were enrolled. Systemic Th-1 (IFN-γ and TNF-α), Th-2 (IL-10 and IL-13), Treg (TGF-β1), and inflammatory cytokines IL-6 and IL-8 concentration were measured in the supernatant of whole blood samples following stimulation with live L. donovani promastigotes using ELISA. Local intralesion IL-10, IFN-γ, and IL-13 expression was measured using Real Time PCR. A significant high concentrations of IFN-γ, TNFα, IL-10, TGFβ, IL-6, and IL-8 were detected in the supernatant of stimulated whole blood samples of ML patients compared with the LST+ve and LST-ve controls. Using Real Time-PCR and primers for various cytokines, a significant high expression of TH2 cytokines IL-10 and IL-13 mRNA was detected in contrast to a low TH1 cytokine IFN-γ mRNA in the mucosal lesion. There is a clear dichotomy in the cytokine response during Mucosal leishmaniasis. A significantly high TH1, inflammatory and Treg cytokines response is produced systemically, in contrast to a significant high TH2 cytokines response in the mucosal lesion.

6

Cite

Share

Bacterial profiling of head lice isolated from the Orang Asli: A first report in Malaysia

Abd Majid, M.A. ; Khoo, J.-J. ; Lim, F.-S. ; Khor, C.-S. ; Loong, S.-K. ; Low, V.-L. ; Lee, H.-Y. ; AbuBakar, S.

Tropical Biomedicine.2020;37(No.4):884-895. doi:https://doi.org/10.47665/tb.37.4.884

This study was carried out to determine from bacterial profiling to the bacterial profiles of head lice among the Orang Asli communities. The head lice were collected from Orang Asli community volunteers. The surface sterilized head lice pools were subjected to genomic DNA extraction while next generation sequencing of the 16S rRNA gene was performed using the Illumina MiSeq platform. Six female and three male head lice identified as Pediculus humanus capitis were collected. A total of 111 368 number of NGS sequencing reads were recorded while another 223 bacterial taxa sequences were obtained. Symbiotic bacteria showed the highest number of reads, with Arsenophonus and Rhodococcus sequences being the most abundant genera in the female and male samples, respectively. The female head lice contained a more distinct microbial diversity. Amongst the pathogenic bacterial species sequences noted were the methicillin-resistant Staphylococcus aureus, Streptobacillus moniliformis, Haemophilus influenzae, Bordetella pertussis and Acinetobacter baumannii. The 16S rRNA genome sequencing revealed a number of rare and pathogenic bacterial species within the head lice of the Orang Asli. The socio-economic practices of the community which involved forest foraging and hunting, and their poor living conditions potentially facilitated the transmission of zoonotic bacterial pathogens, including those found within the head lice. Hence, there is the possibility that the head lice could serve as vectors for the transmission of pathogenic bacteria. This study highlighted the diverse microbial community found within the head lice’s gut of the Orang Asli, with the detection of multiple rare and pathogenic bacteria capable of causing severe infections.

7

Cite

Share

Helminthic parasites in indigenous chickens in Penang Island, Malaysia

Farah Haziqah, M.T. ; Khadijah, S.

Tropical Biomedicine.2020;37(No.4):896-902. doi:https://doi.org/10.47665/tb.37.4.896

Indigenous chicken (Gallus domesticus) is reared for both its meat and eggs. Most consumers prefer the meat probably due to its specific texture and taste. The study was conducted to determine the presence of helminth parasites of 240 indigenous chickens (Gallus domesticus) obtained randomly from 12 divisions in Penang Island, Malaysia. Necropsy findings revealed 14 endoparasite species which parasitized these chickens namely, Acuaria hamulosa, Acuaria spiralis, Amoebotaenia sphenoides, Ascaridia galli, Brachylaima sp., Capillaria spp., Gongylonema ingluvicola, Heterakis gallinarum, Hymenolepis sp., Oxyspirura mansoni, Raillietina echinobothrida, Raillietina tetragona, Syngamus trachea and Tetrameres americana. The high abundance of helminth species observed in this study may be attributed to the free-range scavenging production system, where these indigenous chickens were exposed to intermediate or paratenic hosts of helminths which infect poultry. Besides, sustainable methods of helminthic control measure are necessary in order to enhance indigenous chicken production and eventually improve the economy of the rural farmers.

8

Cite

Share

Distribution of candidemia in Malaysian tertiary care hospital revealed predominance of Candida parapsilosis

Yamin, D. ; Husin, A. ; Harun, A.

Tropical Biomedicine.2020;37(No.4):903-910. doi:https://doi.org/10.47665/tb.37.4.903

. Candida parapsilosis is an important pathogen of healthcare-associated bloodstream infections (BSI) causing high mortality and morbidity in immunocompromised patients in addition to other Candida species including C. albicans, C. tropicalis, C. glabrata, and C. krusei. Knowledge on recent local species distribution and trend is essential. An increase in the proportion of C. parapsilosis candidemia has been recently observed as a result of many risk factors. The distribution of candidemia has been changing in the last three decades. To determine the proportion of different Candida species causing candidemia in a tertiary-care hospital during January 2001 – December 2018, a retrospective study performed in a 853-bedded tertiary-care hospital in north-eastern Malaysia. All cases of candidemia from January-2001 to December-2018 were included, and the review was performed based on patients’ medical records and laboratory database. The frequency of different Candida species was determined. This study showed that out of 1175 patients with candidemia, C. parapsilosis was the most common species contributing to 29.2% (343/1175) of candidemia, followed by C. albicans 20.1% (236/1175), C. tropicalis 18.7% (220/1175), C. glabrata 6.0% (71/1175), C. guilliermondii 3.7% (43/1175), C. rugosa 1.9% (22/1175), C. famata 1.7% (20/1175), C. krusei 1.4% (16/1175), C. dubliniensis 0.8% (9/1175), C. lusitaniae 0.7% (8/1175), C. lipolytica 0.3% (4/1175), C. pelliculosa 0.3% (4/1175), C. haemulonii, C. kefyr, C. utilis and C. inconspicua (1/1175 each). In addition, 14.9% (175/1175) belonged to Candida spp. which were not identified to species level. In conclusion, a different scenario for the proportion of Candida species with C. parapsilosis predominates over C. albicans as a nosocomial pathogen leading to candidemia has been shown in this study

9

Cite

Share

Purification of Plasmodium and Babesia- infected erythrocytes using a non-woven fabric filter

Tao, Z.Y. ; Liu, W.P. ; Dong, J. ; Feng, X.X. ; Yao, D.W. ; Lv, Q.L. ; Ibrahim, U. ; Dong, J.J. ; Culleton, R. ; Gu, W. ; Su, P.P. ; Tao, L. ; Li, J.Y. ; Fang, Q. ; Xia, H.

Tropical Biomedicine.2020;37(No.4):911-918. doi:https://doi.org/10.47665/tb.37.4.911

The purification of parasite-infected erythrocytes from whole blood containing leucocytes is crucial for many downstream genetic and molecular assays in parasitology. Current methodologies to achieve this are often costly and time consuming. Here, we demonstrate the successful application of a cheap and simple Non-Woven Fabric (NWF) filter for the purification of parasitized red blood cells from whole blood. NWF filtration was applied to the malaria-parasitized blood of three strains of mice, and one strain of rat, and to Babesia gibsoni parasitized dog blood. Before and after filtration, the white blood cell (WBC) removal rates and red blood cell (RBC) recovery rates were measured. After NWF filter treatment of rodent malaria-infected blood, the WBC removal rates and RBC recovery rates were, for Kunming mice: 99.51%±0.30% and 86.12%±8.37%; for BALB/C mice: 99.61%±0.15% and 80.74%±7.11%; for C57 mice: 99.71%±0.12% and 84.87%±3.83%; for Sprague-Dawley rats: 99.93%±0.03% and 83.30%±2.96%. Microscopy showed WBCs were efficiently removed from infected dog blood samples, and there was no obvious morphological change of B. gibsoni parasites. NWF filters efficiently remove leukocytes from malaria parasite-infected mouse and rat blood, and are also suitable for filtration of B. gibsoni-infected dog blood.

10

Cite

Share

Detection of Bartonella sp. in ticks and their small mammal hosts in mangrove forests of Peninsular Malaysia

Asyikha, R. ; Sulaiman, N. ; Mohd-Taib, F.S.

Tropical Biomedicine.2020;37(No.4):919-931. doi:https://doi.org/10.47665/tb.37.4.919

Bacteria of the genus Bartonella have been known as emerging zoonotic pathogens for several human diseases including cat scratch disease, Carrion’s disease and trench fever. Numerous species of small mammals have been reported to play a role as a suitable reservoir to many pathogenic Bartonella. These infections are thought to be transmitted through blood-feeding arthropod vectors such as ticks, fleas and lice. The purpose of this study is to detect the presence of Bartonella species from tick samples collected from small mammals in mangrove forests of Peninsular Malaysia. Herein, 38 individual ticks and their small mammals host were evaluated for the presence of Bartonella DNA by conventional PCR targeting the 16S rRNA intergenic spacer region (ITS) and partial sequencing of 460 bp from this locususing Bartonella genus-specific primers. Two tick individuals from Dermacentor auratus and Haemaphysalis hystricis collected from Rattus tiomanicus (host), were PCR-positive for Bartonella DNA amplification. No Bartonella amplification was possible in other tick species (Amblyomma sp.). Phylogenetic analysis of ITS fragments demonstrated that the sequences from ticks were closely related to Bartonella phoceensis, a species that has been reported from black rats (Rattus rattus) in Australia. This is the first report of a Bartonella bacteria detected in ticks from small mammals in Malaysia. Further research should be warranted to investigate the transmission of Bartonella and the potential impact of this zoonotic pathogen in animals and humans as this mangrove ecosystem is significant for local economy and tourism

DISPLAY OPTIONS

Cite

Share

Cite

Share

Cite

Share

Cite

Share

Cite

Share

Cite

Share

Cite

Share

Cite

Share

Cite

Share

Cite

Share