Aleyla Escueta-De Cadiz

University of the Philippines Mindanao · Department of Biological Sciences and Environmental Studies

The 93-hectare Hijo Forest, owned by the Hijo Resources Corporation, is known for its rich flora and fauna species, such as the populations of long-tailed macaques (Macaca fascicularis) and Philippine warty pigs (Sus philippensis). In 2021, the Hijo management reported a mass die-off of Philippine warty pigs in the area due to the African Swine Fev...

Long-tailed macaques in the Philippines are understudied in terms of ecology and behavior, which includes their sexual behaviors, in their natural habitats. Masturbation is a natural, auto-erotic behavior rarely observed in the wild in most non human primates. In this paper, we report an act of masturbation by a free-ranging male long-tailed macaqu...

Schistosomiasis japonica remains a public health concern in many areas of the Philippines. Adequate and updated information is essential to enhance policy and service delivery toward control and elimination. Despite the efforts on schistosomiasis control in the Philippines, some challenges remain in these dimensions. An integrated surveillance syst...

Background and Aim: Schistosomiasis (SCH) japonica is a zoonotic disease that can infect several mammalian hosts. Bovines, particularly water buffaloes, are considered the most important reservoir hosts due to the high levels of schistosome eggs, they excrete into the environment. In the Philippines, the previous studies have revealed a high preval...

This study aimed to determine the prevalence of Entamoeba histolytica in BASECO, an urban slum community situated in Manila Harbor, Manila, Philippines using stool enzyme-linked immunosorbent assay (ELISA). It also aimed to determine if age, sex, and geographic location are contributory factors to the prevalence of E. histolytica. Stool samples wer...

Emerging infectious diseases due to coronavirus (CoV) infections have received significant global attention in the past decade and have been linked to bats as the original source. The diversity, distribution, and host associations of bat CoVs were investigated to assess their potential for zoonotic transmission. Phylogenetic, network, and principal...

This study aimed to determine the prevalence of Entamoeba histolytica and Entamoeba dispar infections among residents in BASECO compound, Manila, Philippines using polymerase chain reaction (PCR). Formalin-ether concentration technique (FECT)-treated stool samples were examined under the light microscope to determine the presence of Entamoeba, helm...

Food poisoning outbreaks are commonly caused by bacterial contamination. These incidents can be minimized by using antimicrobial films that are suitable for use as packaging material. These films can be made by immobilizing an antibacterial agent to a non-toxic polymer matrix. Titanium dioxide (TiO2), when irradiated with ultraviolet light, produce...

[This corrects the article DOI: 10.1371/journal.ppat.1006882.].

The disease state of amebiasis, caused by Entamoeba histolytica, varies from asymptomatic to severe manifestations that include dysentery and extraintestinal abscesses. The virulence factors of the pathogen, and host defense mechanisms, contribute to the outcomes of infection; however, the underlying genetic factors, which affect clinical outcomes,...

The relative mRNA levels of the AIG1 family protein genes that are differentially present in KU27 and KU50. The transcript levels of the genes EHI_025990, EHI_039720, EHI_089440, and EHI_176590, in KU27 and KU50, were measured by DNA microarray and are shown as the percentage relative to that of the RNA polymerase II gene (EHI_056690). Gene IDs wit...

Core genome phylogenetic analysis of E. histolytica strains, and volcano plot based on RPKM value of each ORF between KU27 and KU50. (A) Core genome phylogenetic analysis of E. histolytica strains. Genomes of indicated strains, except for KU27 and KU50, were obtained from Amoeba DB (http://amoebadb.org/amoeba/). Red and blue colors indicate virulen...

RPKM comparisons of ORFs among KU27, KU50, and strains analyzed by Weedall et al. [20]. (XLSX)

Amino acid substitutions characteristic of individual AIG1 family protein clusters. (XLSX)

Adhesion of EHI_176590-HA expressing, or mock, transformants to HRBCs. Microscopic images of trophozoites of EHI_176590-HA-expressing or mock (HA) transformants mixed with HRBCs. Bar: 100 μm. (TIF)

Adhesion of KU27 or KU50 to HRBCs. Microscopic images of trophozoites of KU27, or those of KU50, mixed with HRBCs. Bar: 100 μm (upper panels). Adhesion of KU27 and KU50 to HRBCs. KU27 (open bars) and KU50 (black bar) were co-cultured with HRBCs on ice for 30 min, and adherent HRBCs per ameba were counted. The total number of trophozoites was set to...

Phallacidin staining of the transformant expressing HA-tagged EHI_176590. Trophozoites were fixed with 3.7% paraformaldehyde, permeabilized with 0.2% saponin, incubated with 0.33 μM of BODIPY FL phallacidin (Molecular Probes, Eugine, OR) for 20 min, and stained with anti-HA antibody followed by anti-mouse Alexa 568 conjugated secondary antibody. Th...

Predicted high copy number genes and missing genes in E. histolytica KU27 and KU50. (XLSX)

EHI_176540-HA binding proteins identified by affinity purification. (XLSX)

Grouping and mutual inter-gene percentage identity of AIG1 family protein genes of E. histolytica HM-1:IMSS strain. (XLSX)

Features of AIG1 family proteins in E. histolytica. (A) Multiple sequence alignment (MSA) of the region around switch II of 28 AIG family proteins in E. histolytica. Entire sequences of the 28 proteins were aligned using MAFFT (v7.351b) [82], and visualized using MSAViewer [83]. Only the portion of MSA, which corresponds to the region around switch...

Statistics of HiSeq short reads and mapping status of E. histolytica KU27 and KU50 strains. (XLSX)

AIG1 family protein genes that were differently regulated by environmental changes in Weber et al. [13]. (XLSX)

Validation of gene silencing of EHI_176590, and specificity of the anti- EHI_176590 antibody. (A) Validation of gene silencing of EHI_176590. Reverse transcriptase PCR, of the genes EHI_176590 and RNA polymerase II (EHI_056690), was performed using RNA from an EHI_176590 gene-silenced (gs) strain and pSAP2 mock vector transfected G3 strain. (B) Imm...

Immunofluorescence assay of EHI_176590-HA without permeabilization. EHI_176590-HA-expressing cells were fixed, but not permeabilized, with detergents and were then reacted with an anti-HA antibody. Bar: 20 μm. Images obtained at low, intermediate, and high magnifications are shown. (TIF)

Relative mRNA level of AIG1 family protein genes in HM1:IMSS, KU27, and KU50. Relative expression levels of indicated AIG1 family protein genes, normalized to the expression of RNA polymerase II gene, are shown. Probe sets labeled with “_at” represent a single gene, while “_s_at” or “_x_at” may recognize sequence form splice variants or other genes...

Expression level of control genes, and relative expression levels of EHI_176590, after normalization against three control genes. (A) Expression of RNA polymerase II, actin, and glycerol 3-phosphate dehydrogenase, in Cl6, are shown. Data are based on a previously published DNA microarray study [93]. (B) Relative mRNA levels of EHI_176590 AIG1 gene,...

Encystation is an essential differentiation process for the completion of the life cycle of a group of intestinal protozoa including Entamoeba histolytica, the causative agent of intestinal and extraintestinal amebiasis. However, regulation of gene expression during encystation is poorly understood. To comprehensively understand the process at the...

Plasmodium falciparum is one of the causative agents of malaria in humans. This parasite causes the most severe forms of the disease. In order to combat the disease, it is important to have knowledge about the parasite and its interaction with its host. In this study, we profiled 74 patients admitted to hospital in Tagum, Davao, Philippines who wer...

Encystation, which is cellular differentiation from the motile, proliferative, labile trophozoite form to the dormant, resistant cyst form, is a crucial process found in parasitic and free-living protozoa such as Entamoeba, Giardia, Acanthamoeba, and Balamuthia. Since encystation is an essential process to deal with the adverse external environment...

The quantitative metabolites data during encystation. Normalized average metabolites data of two biological replicate at 0, 0.5, 2, 8, 24, 48 and 120 h are shown. SD, standard deviation of means; N.D, the metabolite concentrations were below the detection limit of the analysis. All the P values were evaluated by the student's t-test. (XLSX)

Oxidative stress modulates amino acid metabolism. The average fold change ± SD (error bars) of metabolites in untreated (control), H2O2, or PQ treated trophozoites with respect to time 0 h is shown. Abbreviations are: SAM, S-adenosylmethionine; SAH, S-adenosylhomocysteine; dcSAMd, decarboxylated S-adenosylmethionine; 5-MTA, 5′-methylthioadenosine;...

Transcriptomic data analyzed in this study. (XLSX)

A novel fecal antigen detection assay for fresh and frozen human samples that detects but does not differentiate Giardia spp, Cryptosporidium spp, and Entamoeba histolytica, the Tri-Combo parasite screen, was compared to three established enzyme-linked immunosorbent assays (ELISAs) at three international sites. It exhibited 97.9% sensitivity and 97...

Patient demographics with and without luminal treatment. (DOC)

Genotyping data of 6 STR loci in 14 clinical samples. (DOC)

Invasive amebic diseases caused by Entamoeba histolytica are increasing among men who have sex with men and co-infection of ameba and HIV-1 is an emerging problem in developed East Asian countries. To characterize the clinical and epidemiological features of invasive amebiasis in HIV-1 patients, the medical records of 170 co-infected cases were ana...

Highly polymorphic, non-coding short tandem repeats (STR) are scattered between the tRNA genes in Entamoeba histolytica in a unique tandemly arrayed organization. STR markers that correlate with the virulence of individual E. histolytica strains have recently been reported. Here we evaluated the usefulness of tRNA-linked STR loci as genetic markers...

In the Philippines, malaria morbidity and mortality have decreased since the 1990s by effective malaria control. Several epidemiological surveys have been performed in the country, but the characteristics of the Plasmodium falciparum populations are not yet fully understood. In this study, the genetic structure of P. falciparum populations in the P...

Allele frequencies and number of isolates (n) of 10 microsatellite loci of the three Plasmodium falciparum populations in the Philippines. Allele names refer to the base pair sizes of the product of polymerase chain reaction.

Percentages of multiple-genotype infection (MGI) of msp1 and msp2 of the three Plasmodium falciparum populations in the Philippines. No. indicates the number of isolates for each measure.msp1: block 2 of merozoite surface protein-1 gene, msp2: block 3 of merozoite surface protein-2 gene, msp1 or msp2 represents the percentage of isolates that showe...

Specific mutations in the pfcrt and pfmdr1 genes have been reported to be associated with chloroquine-resistant falciparum malaria parasites worldwide. These genetic markers are considered to be useful tools for the elucidation of several aspects of the epidemiology of drug resistant malaria. In this study, Plasmodium falciparum isolates from three...

Malaria is one of the major infectious diseases in the Philippines. It is being targeted for control through sustained early diagnosis, treatment and mosquito control. It is in this light that understanding the genetic background of the parasite population is important not only for basic biology of the organism but also for epidemiology and control...

In vitro drug susceptibility testing of Plasmodium falciparum must be conducted immediately after collecting a sample of the patient‘s blood; otherwise the parasites may weaken and the culture fail. Collecting blood samples from individuals in areas far from the field station or clinic where in vitro testing is conducted requires a reliable method...