2.Urinary schistosomiasis and malaria associated anemia in Ethiopia.
Ketema DERIBEW ; Zinaye TEKESTE ; Beyene PETROS ; Lim Boon HUAT
Asian Pacific Journal of Tropical Biomedicine 2013;3(4):307-310
OBJECTIVETo assess the prevalence of anemia in children with urinary schistosomiasis, malaria and concurrent infections by the two diseases.
METHODSUrine and blood samples were collected from 387 children (216 males and 171 females) to examine urinary schistosomiasis and malaria and to determine hemoglobin concentration at Hassoba and Hassoba Buri village in Amibara woreda, Afar region, Ethiopia.
RESULTSThe overall prevalence of urinary schistosomiasis and Plasmodium falciparum malaria was 24.54% and 6.20% respectively. Only 2.84% of children carried concurrent infections of both parasites. There was high percentage of anemic patients (81.81%) in the coinfected cases than in either malaria (33.3%) or schistosomiasis (38.94%) cases. There was significantly low mean hemoglobin concentration in concurrently infected children than non-infected and single infected (P<0.05). The mean hemoglobin concentration between Plasmodium falciparum and S. haematobium infected children showed no significant difference (P>0.05). The level of hemoglobin was negatively correlated with the number of S. haematobium eggs/10 mL urine (r=-0.6) and malaria parasitemia (r=-0.53).
CONCLUSIONSThe study showed that anemia is higher in concurrently infected children than non-infected and single infected. Furthermore, level of hemoglobin was negatively correlated with the number of S. haematobium eggs and malaria parsitemia. Therefore, examination of hemoglobin status in patients co-infected with malaria and schistosomiasis is important to reduce the risk of anemia and to improve health of the community.
Adolescent ; Anemia ; diagnosis ; epidemiology ; etiology ; Child ; Child, Preschool ; Ethiopia ; Female ; Humans ; Malaria ; complications ; Male ; Prevalence ; Schistosomiasis haematobia ; complications ; diagnosis
3.Experimental evaluation of Candonocypris novaezelandiae (Crustacea: Ostracoda) in the biocontrol of Schistosomiasis mansoni transmission.
Fouad YOUSIF ; Sherif HAFEZ ; Samia El BARDICY ; Menerva TADROS ; Hoda Abu TALEB ; Lim Boon HUAT
Asian Pacific Journal of Tropical Biomedicine 2013;3(4):267-272
OBJECTIVETo test Candonocypris novaezelandiae (Baird) (C. novaezelandiae), sub-class Ostracoda, obtained from the Nile, Egypt for its predatory activity on snail, Biomphalaria alexandrina (B. alexandrina), intermediate host of Schistosoma mansoni (S. mansoni) and on the free-living larval stages of this parasite (miracidia and cercariae).
METHODSThe predatory activity of C. novaezelandiae was determined on B. alexandrina snail (several densities of eggs, newly hatched and juveniles). This activity was also determined on S. mansoni miracidia and cercariae using different volumes of water and different numbers of larvae. C. novaezelandiae was also tested for its effect on infection of snails and on the cercarial production.
RESULTSC. novaezelandiae was found to feed on the eggs, newly hatched and juvenile snails, but with significant reduction in the consumption in the presence of other diet like the blue green algae (Nostoc muscorum). This ostracod also showed considerable predatory activity on the free-living larval stages of S. mansoni which was affected by certain environmental factors such as volume of water, density of C. novaezelandiae and number of larvae of the parasite.
CONCLUSIONSThe presence of this ostracod in the aquatic habitat led to significant reduction of snail population, infection rate of snails with schistosme miracidia as well as of cercarial production from the infected snails. This may suggest that introducing C. novaezelandiae into the habitat at schistosome risky sites could suppress the transmission of the disease.
Animals ; Crustacea ; physiology ; Pest Control ; Pest Control, Biological ; Predatory Behavior ; Schistosoma mansoni ; Schistosomiasis mansoni ; prevention & control ; transmission
4.Detection of Entamoeba histolytica in experimentally induced amoebic liver abscess: comparison of three staining methods.
Tan Zi NING ; Wong Weng KIN ; Shaymoli MUSTAFA ; Arefuddin AHMED ; Rahmah NOORDIN ; Tan Gim CHEONG ; Olivos-Garcia ALFONSO ; Lim Boon HUAT
Asian Pacific Journal of Tropical Biomedicine 2012;2(1):61-65
OBJECTIVETo compare the efficacy of three different tissue stains, namely haematoxylin and eosin (H&E), periodic-acid Schiff (PAS) and immunohistochemical (IHC) stains for detection of Entamoeba histolytica (E. histolytica) trophozoites in abscessed liver tissues of hamster.
METHODSAmoebic liver abscess was experimentally induced in a hamster by injecting 1 × 10(6) of axenically cultured virulent E. histolytica trophozoites (HM1-IMSS strain) into the portal vein. After a week post-inoculation, the hamster was sacrificed and the liver tissue sections were stained with H&E, PAS and IHC stains to detect the amoebic trophozoite.
RESULTSThe three stains revealed tissue necrosis and amoebic trophozoites, but with varying clarity. H&E and PAS stained the trophozoites pink and magenta, respectively, however it was difficult to differentiate the stained trophozoites from the macrophages because of their similarity in size and morphology. On the other hand, IHC stain revealed distinct brown appearance of the trophozoites in the infected liver tissues.
CONCLUSIONSIt can be concluded that out of the three stains, IHC is the best for identification of E. histolytica trophozoites in tissue sections.
Animals ; Disease Models, Animal ; Entamoeba histolytica ; cytology ; isolation & purification ; Histocytochemistry ; methods ; Immunohistochemistry ; methods ; Liver Abscess, Amebic ; diagnosis ; pathology ; Male ; Mesocricetus ; Microscopy ; Parasitology ; methods ; Staining and Labeling ; methods ; Trophozoites ; cytology
5.Reverse vaccinology approach for the identification and characterization of outer membrane proteins of Shigella flexneri as potential cellular- and antibody-dependent vaccine candidates
Chiuan Yee LEOW ; Ada KAZI ; Che Muhammad Khairul HISYAM ISMAIL ; Candy CHUAH ; Boon Huat LIM ; Chiuan Herng LEOW ; Kirnpal Kaur BANGA SINGH
Clinical and Experimental Vaccine Research 2020;9(1):15-25
6. Multiplex real-time PCR revealed very high prevalence of soil-transmitted helminth infections among aborigines in Peninsular Malaysia
Nurulhasanah OTHMAN ; Noorizan MISWAN ; Rahmah NOORDIN ; Weng-Kin WONG ; Boon-Huat LIM
Asian Pacific Journal of Tropical Medicine 2020;13(12):550-556
Objective: To determine the true prevalence of soil-transmitted helminth infections in the Malaysian aborigines using real-time PCR. Methods: A total of 122 aborigines from seven tribes were recruited from settlements and nearby hospitals which served the communities, located in four states in Peninsular Malaysia. The stool samples were examined for the presence of soil-transmitted helminth using real-time PCR and microscopy. The latter included the direct wet mount and formalin-ether concentration technique (FECT). The infection load in FECT-positive samples was determined by the Kato-Katz method. Rotorgene real-time analyzer detected five helminth species using two sets of assays. Results: The real-time PCR detected soil-transmitted helminth in 98.4% samples (n=122), which were 1.56 times higher than by microscopy. Ascaris lumbricoides and Trichuris trichiura were detected in more than 90% of the samples, while hookworm was detected in 46.7% (Necator americanus) and 13.9% (Ancylostoma sp.) of the samples. Comparison with previous reports on the Malaysian aborigines showed that the real-time PCR markedly improved the detection of Ascaris lumbricoides, hookworm and Strongyloides stercoralis. The real-time PCR detected poly-helminths in 92.6% of the samples compared to 28.7% by microscopy. In addition, 27 samples (22.1%) showed amplification of Strongyloides stercoralis DNA. Conclusions: The real-time PCR showed very high prevalence rates of soil-transmitted helminth infections in the aborigines and is the recommended method for epidemiological investigation of soil-transmitted helminth infections in this population.
7. Entamoeba histolytica acetyl-CoA synthetase: Biomarker of acute amoebic liver abscess
Lim Boon HUAT ; Wong Weng KIN ; Siti Shafiqah Anaqi AZHAM ; Lee Zhi JIE ; Guee Cher CHING ; Foo Phiaw CHONG ; Pim Chau DAM ; Alfonso Olivos GARCIA ; Tan Zi NING ; Rahmah NOORDIN
Asian Pacific Journal of Tropical Biomedicine 2014;4(6):446-450
Objective: To characterize the Entamoeba histolytica (E. histolytica) antigen(s) recognized by moribound amoebic liver abscess hamsters. Methods: Crude soluble antigen of E. histolytica was probed with sera of moribund hamsters in 1D- and 2D-Western blot analyses. The antigenic protein was then sent for tandem mass spectrometry analysis. The corresponding gene was cloned and expressed in Escherichia coli BL21-AI to produce the recombinant E. histolytica ADP-forming acetyl-CoA synthetase (EhACS) protein. A customised ELISA was developed to evaluate the sensitivity and specificity of the recombinant protein. Results: A ~75 kDa protein band with a pI value of 5.91-6.5 was found to be antigenic; and not detected by sera of hamsters in the control group. Tandem mass spectrometry analysis revealed the protein to be the 77 kDa E. histolytica ADP-forming acetyl-CoA synthetase (EhACS). The customised ELISA results revealed 100% sensitivity and 100% specificity when tested against infected (n=31) and control group hamsters (n=5) serum samples, respectively. Conclusions: This finding suggested the significant role of EhACS as a biomarker for moribund hamsters with acute amoebic liver abscess (ALA) infection. It is deemed pertinent that future studies explore the potential roles of EhACS in better understanding the pathogenesis of ALA; and in the development of vaccine and diagnostic tests to control ALA in human populations.
8.More microinvasive foci in larger tumours of breast ductal carcinoma in situ.
Xiao-Yang CHEN ; Aye Aye THIKE ; Johnathan Xiande LIM ; Boon Huat BAY ; Puay Hoon TAN
Singapore medical journal 2023;64(8):493-496
INTRODUCTION:
Microinvasion (Mi) is often thought to be an interim stage between ductal carcinoma in situ (DCIS) and invasive ductal carcinoma. This study aimed to investigate the potential influence of Mi on survival and assess its correlations with clinicopathological parameters, prognosis and molecular markers.
METHODS:
The number of Mi foci in a cohort of 66 DCIS-Mi cases was assessed from haematoxylin and eosin-stained sections. Disease-free survival, clinicopathological parameters and biomarker expression were correlated with the number of Mi foci.
RESULTS:
Higher numbers of Mi foci were found in larger tumours (P = 0.031).
CONCLUSION
Greater extent of DCIS is associated with multifocal Mi.
Humans
;
Female
;
Carcinoma, Intraductal, Noninfiltrating
;
Prognosis
;
Disease-Free Survival
;
Progression-Free Survival
;
Breast Neoplasms
;
Carcinoma, Ductal, Breast/pathology*
;
Neoplasm Invasiveness
9.Entamoeba histolytica acetyl-CoA synthetase: biomarker of acute amoebic liver abscess.
Lim Boon HUAT ; Alfonso Olivos GARCIA ; Tan Zi NING ; Wong Weng KIN ; Rahmah NOORDIN ; Siti Shafiqah Anaqi AZHAM ; Lee Zhi JIE ; Guee Cher CHING ; Foo Phiaw CHONG ; Pim Chau DAM
Asian Pacific Journal of Tropical Biomedicine 2014;4(6):446-450
OBJECTIVETo characterize the Entamoeba histolytica (E. histolytica) antigen(s) recognized by moribound amoebic liver abscess hamsters.
METHODSCrude soluble antigen of E. histolytica was probed with sera of moribund hamsters in 1D- and 2D-Western blot analyses. The antigenic protein was then sent for tandem mass spectrometry analysis. The corresponding gene was cloned and expressed in Escherichia coli BL21-AI to produce the recombinant E. histolytica ADP-forming acetyl-CoA synthetase (EhACS) protein. A customised ELISA was developed to evaluate the sensitivity and specificity of the recombinant protein.
RESULTSA ∼75 kDa protein band with a pI value of 5.91-6.5 was found to be antigenic; and not detected by sera of hamsters in the control group. Tandem mass spectrometry analysis revealed the protein to be the 77 kDa E. histolytica ADP-forming acetyl-CoA synthetase (EhACS). The customised ELISA results revealed 100% sensitivity and 100% specificity when tested against infected (n=31) and control group hamsters (n=5) serum samples, respectively.
CONCLUSIONSThis finding suggested the significant role of EhACS as a biomarker for moribund hamsters with acute amoebic liver abscess (ALA) infection. It is deemed pertinent that future studies explore the potential roles of EhACS in better understanding the pathogenesis of ALA; and in the development of vaccine and diagnostic tests to control ALA in human populations.