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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 macaque in a beach forest at an eco-tourism site in Tagum City, Mindanao Island, Philippines. The masturbation was performed by a sub-adult male resting on the handrail of a wooden staircase. A few seconds after masturbation, ejaculation was achieved. Although more detailed observations are needed, it is likely that limited access to female mates contributed to the male's self-stimulation. This further calls for more scientific explorations on reproductive and non-reproductive sexual behaviors of long-tailed macaques in the wild. Moreover, this can be crucial for conservation purposes such as its application to the non-invasive collection of semen samples in wild populations. [ABSTRACT FROM AUTHOR]

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, produces free radicals capable of killing bacteria. Sodium alginate (SA) is an edible polymer taken from brown algae. Both TiO2 and SA are approved by the U.S. Food and Drug Administration as an additive in food. Therefore, composites made from SA and TiO2 are considered safe. SA/TiO2 nanocomposite films can be activated by both fluorescent and black light lamps. As evidenced by the percent color removal of methylene blue, the photocatalytic activity appeared to be higher when exposed to black light. SA/TiO2 composite films were exposed to fluorescent and black light lamps for 5 h in the presence of Escherichia coli and Staphylococcus aureus. Under fluorescent lamps, the photocatalytic activity of the SA/TiO2 composite films was enough to at least inhibit the proliferation of both bacteria. However, exposure of the 5% SA/TiO2 composite film to black light resulted to a 0 log count for both bacteria. These results showed that SA/TiO2 composite films can therefore be used in the food industry as an antibacterial film. [ABSTRACT FROM AUTHOR]

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, remain to be fully elucidated. To identify these genetic factors in E. histolytica, we used Illumina next-generation sequencing to conduct a comparative genomic analysis of two clinical isolates obtained from diarrheal and asymptomatic patients (strains KU50 and KU27, respectively). By mapping KU50 and KU27 reads to the genome of a reference HM-1:IMSS strain, we identified two genes (EHI_089440 and EHI_176590) that were absent in strain KU27. In KU27, a single AIG1 (avrRpt2-nduced ene 1) family gene (EHI_176590) was found to be deleted, from a tandem array of three AIG1 genes, by homologous recombination between the two flanking genes. Overexpression of the EHI_176590 gene, in strain HM-1:IMSS cl6, resulted in increased formation of cell-surface protrusions and enhanced adhesion to human erythrocytes. The EHI_176590 gene was detected by PCR in 56% of stool samples from symptomatic patients infected with E. histolytica, but only in 15% of stool samples from asymptomatic individuals. This suggests that the presence of the EHI_176590 gene is correlated with the outcomes of infection. Taken together, these data strongly indicate that the AIG1 family protein plays a pivotal role in E. histolytica virulence via regulation of host cell adhesion. Our in-vivo experiments, using a hamster liver abscess model, showed that overexpression or gene silencing of EHI_176590 reduced and increased liver abscess formation, respectively. This suggests that the AIG1 genes may have contrasting roles in virulence depending on the genetic background of the parasite and host environment. [ABSTRACT FROM AUTHOR]

Abstract: 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 identifying virulent and avirulent strains of E. histolytica from 37 Japanese E. histolytica samples (12 diarrheic/dysenteric, 20 amebic liver abscess (ALA), and 5 asymptomatic cases). Twenty three genotypes, assigned by combining the STR sequence types from all 6 STR loci, were identified. One to 8 new STR sequence types per locus were also discovered. Genotypes found in asymptomatic isolates were highly polymorphic (4 out of 5 genotypes were unique to this group), while in symptomatic isolates, almost half of the genotypes were shared between diarrhea/dysentery and ALA. One asymptomatic isolate (KU27) showed unique STR patterns in 4 loci. This strain, though associated with the typical pathogenic zymodeme II, failed to induce amebic liver abscess by animal challenge, which suggests that inherently avirulent E. histolytica strains exist, that are associated with unique genotypes. Furthermore, STR genotyping and in vivo challenge of 2 other asymptomatic isolates (KU14 and KU26) verified the covert virulence of these strains. [Copyright &y& Elsevier]

• Taxonomic classification, proposed origin and geographic spread of Oncomelania hupensis and genetic differentiation of Oncomelania hupensis quadrasi • Biology of Oncomelania hupensis quadrasi • Snail Control • Use of RS/GIS in Snail Research • Way Forward Oncomelania hupensis quadrasi is the snail intermediate host of Schistosoma japonicum in the Philippines. It was discovered by Dr. Marcos Tubangui in 1932 more than two decades after the discovery of the disease in the country in 1906. This review, the first for O. h. quadrasi , presents past and present works on the taxonomy, biology, ecology, control, possible paleogeographic origin of the snail intermediate host and future in research, control and surveillance of the snail. Extensive references are made of other subspecies of O. hupensis such as the subspecies in China for which majority of the advances has been accomplished. Contrasting views on whether the snail is to be considered an independent species of Oncomelania or as one of several subspecies of Oncomelania hupensis are presented. Snail control methods such as chemical methods using synthetic and botanical molluscicides, environmental manipulation and biological control are reviewed. Use of technologies such as Remote Sensing, Geographical Information System and landscape genetics is stressed for snail surveillance. Control and prevention efforts in the Philippines have consistently focused on mass drug administration which has proved inadequate in elimination of the disease. An integrated approach that includes snail control, environmental sanitation and health education has been proposed. Population movement such as migration for employment and economic opportunities and ecotourism and global climate change resulting in heavy rains and flooding challenge the gains of control and elimination efforts. Concern for possible migration of snails to non-endemic areas is expressed given the various changes both natural and mostly man-made favoring habitat expansion. [ABSTRACT FROM AUTHOR]

In the Philippines, ten NTDs are prevalent, but only six namely LF, schistosomiasis, STH, food-borne trematodiases, rabies and leprosy are considered to be of public health importance. The 81 provinces in the country are endemic for at least one of these NTDs. Others may be endemic for two or even more of these diseases. Since 2000, after the Philippines accepted and implemented the WHO guidelines for NTDs prevention, control and elimination, significant progress has been achieved in reducing the magnitude of NTDs endemic in the country. Since 2009, out of 46 filariasis-endemic provinces, the number of provinces that has eliminated LF has progressively increased so that by 2015, 76% are already LF-free. By 2019, only four provinces remain endemic for LF. For schistosomiasis, as of 2012, report from the Department of Health (DOH) put the number of high endemic provinces at 10, moderately endemic at 6 and low to elimination levels at 12. For STH, results of the National Parasite Survey in the Philippines among school-aged children conducted in 2015 by the Research Institute for Tropical Medicine, the research arm of the Philippine DOH, however, showed that the overall cumulative prevalence was 28.4% with a prevalence range between 7.1% and 67.4%. The figures are way above the <20% prevalence standard set by the World Health Organization. Control and prevention efforts for FBTs just gained traction with the call of WHO for elimination of NTDs in 2015. There is an urgent need to update information by an intensive national baseline survey that can validate previous data as well as generate new information on the magnitude of the FBT problem in the Philippines. For leprosy, elimination activities have been intensified in high prevalence areas and from 2009 to 2013, case detection and prevalence were sustained at <1.0 per 10,000 population. Rabies elimination activities have been effective that by 2011, only five regions out of 16 remained with the highest number of rabies cases. In a period of seven years from 2010 to 2017, the number of rabies-free provinces and municipalities increased from 3 to 49. Problems continue to hound the NTD programmes in the Philippines as priorities shift to more urgent health problems in a country that is weighed down not only by the triple burden of disease but serious health consequences of emergencies and disasters and the fast-growing population itself. Paradigm shifts are suggested to replace the traditional and conventional perspectives of control. These include change from disease approach to intervention approach to allow for integration of strategies targeting several NTDs and multisectoral, multidisciplinary approach requiring strong, viable and sustainable partnerships involving various agencies of the government, public and private sector, pharmaceuticals, academe, researchers, local government units and the endemic communities themselves. [ABSTRACT FROM AUTHOR]

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

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 97.0% specificity, with positive and negative predictive values of 93.4% and 99.1%, respectively. The Tri-Combo test proved a reliable means to limit the use of individual parasite ELISAs to positive samples.

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 environmental changes during the life cycle, and often integral to the transmission of the diseases, biochemical understanding of the process potentially provides useful measures against the infections caused by this group of protozoa. In this study, we investigated metabolic and transcriptomic changes that occur during encystation in Entamoeba invadens, the reptilian sibling of mammal-infecting E. histolytica, using capillary electrophoresis-tandem mass spectrometry-based metabolite profiling and DNA microarray-based expression profiling. As the encystation progressed, the levels of majority of metabolites involved in glycolysis and nucleotides drastically decreased, indicating energy generation is ceased. Furthermore, the flux of glycolysis was redirected toward chitin wall biosynthesis. We found remarkable temporal increases in biogenic amines such as isoamylamine, isobutylamine, and cadaverine, during the early period of encystation, when the trophozoites form large multicellular aggregates (precyst). We also found remarkable induction of γ-aminobutyric acid (GABA) during encystation. This study has unveiled for the first time the dynamics of the transcriptional and metabolic regulatory networks during encystation, and should help in better understanding of the process in pathogenic eukaryotes, and further development of measures controlling infections they cause.

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 analyzed retrospectively, and E. histolytica genotype was assayed in 14 cases. In this series of HIV-1-infected patients, clinical presentation of invasive amebiasis was similar to that described in the normal host. High fever, leukocytosis and high CRP were associated with extraluminal amebic diseases. Two cases died from amebic colitis (resulting in intestinal perforation in one and gastrointestinal bleeding in one), and three cases died from causes unrelated to amebiasis. Treatment with metronidazole or tinidazole was successful in the other 165 cases. Luminal treatment was provided to 83 patients following metronidazole or tinidazole treatment. However, amebiasis recurred in 6 of these, a frequency similar to that seen in patients who did not receive luminal treatment. Recurrence was more frequent in HCV-antibody positive individuals and those who acquired syphilis during the follow-up period. Various genotypes of E. histolytica were identified in 14 patients but there was no correlation between genotype and clinical features. The outcome of metronidazole and tinidazole treatment of uncomplicated amebiasis was excellent even in HIV-1-infected individuals. Luminal treatment following metronidazole or tinidazole treatment does not reduce recurrence of amebiasis in high risk populations probably due to amebic re-infection.