Toxicological Evaluation of Kaempferol and Linearolactone as Treatments for Amoebic Liver Abscess Development in Mesocricetus auratus.

Several studies with kaempferol (KP) and linearolactone (LL) have demonstrated their antiparasitic activity. However, the toxicity of these treatments is unknown. Therefore, this study aimed to evaluate the possible toxicological effects of intraperitoneal (i.p.) administration of KP or LL on the amoebic liver abscess model (ALA) in Mesocricetus auratus. An ALA was induced in male hamsters with 1.5 × 105Entamoeba histolytica (E. histolytica) trophozoites inoculated in the left hepatic lobe. The lesion evolved for 4 days, and then KP (5 mg/kg body weight/day) or LL (10 mg/kg body weight/day) was administered for 4 consecutive days. Then, magnetic resonance imaging (MRI), paraclinical analyses, and necropsy for histopathological evaluation were performed. There was similar ALA inhibition by KP (19.42%), LL (28.16%), and metronidazole, the antiamoebic control (20.87%) (p ≤ 0.05, analysis of variance [ANOVA]). There were hepatic and renal biochemical alterations in all treatment groups, mainly for KP (aspartate aminotransferase: 347.5 ± 37.5 U/L; blood urea nitrogen: 19.4 ± 1.9 g/dL; p ≤ 0.05, ANOVA). Lesions found in the organs were directly linked to the pathology. In conclusion, KP and LL decreased ALA development and exerted fewer toxicological effects compared with metronidazole. Therefore, both compounds exhibit therapeutic potential as an alternative treatment of amoebiasis caused by E. histolytica. However, additional clinical studies in different contexts are required to reaffirm this assertion.

Epidemiological characteristics of mortality from infectious intestinal diseases (diarrhea) Paraguay (2015-2019)

Introduction: Infectious intestinal diseases (diarrhea) are a major cause of morbidity and mortality worldwide. In 2015, it constituted the ninth leading cause of death for all ages. Objective: To describe the epidemiological characteristics of mortality due to infectious intestinal diseases (diarrhea) in Paraguay from 2015 to 2019. Methods: Descriptive, ecological, cross-sectional, retrospective, and non-probabilistic sampling of consecutive cases was performed. ICD-10 deaths included cholera (A01), typhoid and paratyphoid fever (A01), shigellosis (A03), other bacterial intestinal infections (A04), other bacterial food poisoning (A05), amebiasis (A06), other intestinal diseases due to protozoa (A07), intestinal infections due to viruses (A08), and diarrhea and gastroenteritis of presumed infectious origin (A09). Open access data were obtained from the WEB page of the General Directorate of Strategic Information in Health of the MSP and BS of all the Departments of the country. Crude and adjusted rates (per 100,000 inhabitants) were calculated. Excel and EPI INFO 7.0 were used. Results: 495 deaths were registered; the highest prevalence was in 2019 (adjusted rate of 1.83) and the lowest in 2017 (1.36). The months with the highest mortality rates were January and July (9.9%). 51.72% were women (256), 30.91% were over 80 years old and 28.28% (140) were under 5 years old, average age 50.8, single 56.77% (281) and without any type of education 41.82% (207). A total of 80.61% (399) of the respondents resided in urban areas. The highest rates were registered in Boquerón (33.3) and Amambay (15.2). Diarrhea and gastroenteritis of infectious origin accounted for 95.56% of the cases (473). Discussion: There was a high percentage of mortality from infectious diarrhea. Extremes of life were the most vulnerable populations.

Introducción: Las enfermedades infecciosas intestinales (diarrea) son una causa importante de morbilidad y mortalidad a nivel mundial. En 2015, constituyeron la novena causa principal de muerte para todas las edades. Objetivo: describir las características epidemiológicas de la mortalidad por enfermedades infecciosas intestinales (diarreas) en Paraguay durante los años 2015 al 2019. Metodología: Estudio descriptivo, ecológico, transversal, retrospectivo, muestreo no probabilístico de casos consecutivos. Se consideraron los óbitos del CIE - 10, que incluyen al cólera (A01), fiebres tifoidea y paratifoidea (A01), shigelosis (A03), otras infecciones intestinales bacterianas (A04), otras intoxicaciones alimentarias bacterianas (A05), amebiasis (A06), otras enfermedades intestinales debidas a protozoarios (A07), infecciones intestinales debidas a virus (A08) y diarrea y gastroenteritis de presunto origen infeccioso (A09). Se utilizaron datos de acceso abierto de la página WEB de la Dirección General de Información Estratégica en Salud del MSP y BS de todos los Departamentos del país. Se calcularon tasas crudas y ajustadas (por 100.000 habitantes). Se utilizaron Excel y EPI INFO 7.0. Resultados: Se registraron 495 muertes, la mayor prevalencia fue en 2019 (tasa ajustada de 1,83) y menor en 2017 (1,36). Los meses con mayor mortalidad fueron enero y julio (9,9%). El 51,72% fueron mujeres (256), 30,91% mayores de 80 años y 28,28% (140) menores de 5 años, edad promedio 50,8, solteros 56,77% (281) y sin ningún tipo de educación 41,82% (207). El 80,61% (399) residía en área urbana. Las mayores tasas se registraron en Boquerón (33,3) y Amambay (15,2). El 95,56% (473) fueron diarreas y gastroenteritis de origen infeccioso. Discusión: Se registra alto porcentaje de mortalidad de diarreas de origen infeccioso. Los extremos de la vida constituyen la población más vulnerable.

Enteropathogenic Escherichia coli modulates the virulence and pathogenicity of Entamoeba dispar.

Amoebiasis is a disease caused by Entamoeba histolytica, affecting the large intestine of humans and occasionally leading to extra-intestinal lesions. Entamoeba dispar is another amoeba species considered commensal, although it has been identified in patients presenting with dysenteric and nondysenteric colitis, as well as amoebic liver abscess. Amoebic virulence factors are essential for the invasion and development of lesions. There is evidence showing that the association of enterobacteria with trophozoites contributes to increased gene expression of amoebic virulence factors. Enteropathogenic Escherichia coli is an important bacterium causing diarrhea, with high incidence rates in the world population, allowing it to interact with Entamoeba sp. in the same host. In this context, this study aims to evaluate the influence of enteropathogenic Escherichia coli on ACFN and ADO Entamoeba dispar strains by quantifying the gene expression of virulence factors, including galactose/N-acetyl-D-galactosamine-binding lectin, cysteine proteinase 2, and amoebapores A and C. Additionally, the study assesses the progression and morphological aspect of amoebic liver abscess and the profile of inflammatory cells. Our results demonstrated that the interaction between EPEC and ACFN Entamoeba dispar strains was able to increase the gene expression of virulence factors, as well as the lesion area and the activity of the inflammatory infiltrate. However, the association with the ADO strain did not influence the gene expression of virulence factors. Together, our findings indicate that the interaction between EPEC, ACFN, and ADO Entamoeba dispar strains resulted in differences in vitro and in vivo gene expression of Gal/GalNAc-binding lectin and CP2, in enzymatic activities of MPO, NAG, and EPO, and consequently, in the ability to cause lesions.

Encefalitis amebiana granulomatosa por Balamuthia mandrillaris en Chile confirmada con secuenciación de ADN / Granulomatous amoebic encephalitis due to Balamuthia mandrillaris in Chile confirmed with DNA sequencing

Las enfermedades causadas por amebas de vida libre son infecciones oportunistas que pueden tener un curso fatal. Pueden producir afecciones diseminadas graves con compromiso del sistema nervioso central, como la encefalitis amebiana granulomatosa. Esta infección es cada vez más frecuente en América Latina, aunque se reconocen tardíamente debido a la similitud con otras patologías o porque es inusual incluirla en el diagnóstico diferencial. Comunicamos un caso fatal de una encefalitis amebiana granulomatosa por Balamuthia mandrillaris en una niña de 10 años. Destacamos la gravedad de la afectación cerebral y la falta de esquemas antimicrobianos validados para su tratamiento. Hoy en el mundo esta infección es considerada una enfermedad emergente, influenciada por el cambio climático, lo que llama a estar atentos a su presencia.

Diseases caused by free-living amoebae are opportunistic infections that can have a fatal course. They can cause very serious disseminated conditions with involvement of the central nervous system such as granulomatous amoebic encephalitis. This infection has become more common in Latin America, although its recognition is late due to the similarity with other pathological conditions or because it is unusual to include it in the differential diagnosis. We report a fatal case of granulomatous amoebic encephalitis due to Balamuthia mandrillaris in a 10-year-old girl. We highlight the severity of the brain involvement and the lack of validated schemes for its treatment. Today in the world this infection is considered an emerging disease, influenced by climate change, which calls for being attentive to its presence.

Genome-Wide Classification of Myb Domain-Containing Protein Families in Entamoeba invadens.

Entamoeba histolytica, the causative agent of amebiasis, is the third leading cause of death among parasitic diseases globally. Its life cycle includes encystation, which has been mostly studied in Entamoeba invadens, responsible for reptilian amebiasis. However, the molecular mechanisms underlying this process are not fully understood. Therefore, we focused on the identification and characterization of Myb proteins, which regulate the expression of encystation-related genes in various protozoan parasites. Through bioinformatic analysis, we identified 48 genes in E. invadens encoding MYB-domain-containing proteins. These were classified into single-repeat 1R (20), 2R-MYB proteins (27), and one 4R-MYB protein. The in-silico analysis suggests that these proteins are multifunctional, participating in transcriptional regulation, chromatin remodeling, telomere maintenance, and splicing. Transcriptomic data analysis revealed expression signatures of eimyb genes, suggesting a potential orchestration in the regulation of early and late encystation-excystation genes. Furthermore, we identified probable target genes associated with reproduction, the meiotic cell cycle, ubiquitin-dependent protein catabolism, and endosomal transport. In conclusion, our findings suggest that E. invadens Myb proteins regulate stage-specific proteins and a wide array of cellular processes. This study provides a foundation for further exploration of the molecular mechanisms governing encystation and unveils potential targets for therapeutic intervention in amebiasis.

Could giant viruses be considered as a biotechnological tool for preventing and controlling Acanthamoeba infections?

AIM: The aim of the study was to evaluate the efficiency of mimivirus as a potential therapeutic and prophylactic tool against Acanthamoeba castellanii, the etiological agent of Acanthamoeba keratitis, a progressive corneal infection, that is commonly associated with the use of contact lenses and can lead to blindness if not properly treated. METHODS AND RESULTS: Mimivirus particles were tested in different multiplicity of infection, along with commercial multipurpose contact lenses' solutions, aiming to assess their ability to prevent encystment and excystment of A. castellanii. Solutions were evaluated for their amoebicidal potential and cytotoxicity in MDCK cells, as well as their effectiveness in preventing A. castellanii damage in Madin-Darby canine kidney (MDCK) cells. Results indicated that mimivirus was able to inhibit the formation of A. castellanii cysts, even in the presence of Neff encystment solution. Mimivirus also showed greater effectiveness in controlling A. castellanii excystment compared to commercial solutions. Additionally, mimivirus solution was more effective in preventing damage caused by A. castellanii, presented greater amoebicidal activity, and were less cytotoxic to MDCK cells than commercial MPS. CONCLUSIONS: Mimivirus demonstrates a greater ability to inhibit A. castellanii encystment and excystment compared to commercial multipurpose contact lens solutions. Additionally, mimivirus is less toxic to MDCK cells than those commercial solutions. New studies utilizing in vivo models will be crucial for confirming safety and efficacy parameters.

Therapeutic potential of antimicrobial peptides against pathogenic protozoa.

Protozoal infections cause significant morbidity and mortality in humans and animals. The use of several antiprotozoal drugs is associated with serious adverse effects and resistance development, and drugs that are more effective are urgently needed. Microorganisms, mammalian cells and fluids, insects, and reptiles are sources of antimicrobial peptides (AMPs) that act against pathogenic microorganisms; these AMPs have been widely studied as a promising alternative therapeutic option to conventional antibiotics, aiming to treat infections caused by multidrug-resistant pathogens. One advantage of AMP molecules is their adaptability, as they can be easily fine-tuned for broad-spectrum or targeted activity by changing the amino acid residues in their sequence. Consequently, these variations in structural and physicochemical properties can alter the antimicrobial activities of AMPs and decrease resistance development. This article presents an overview of peptide activities against amebiasis, giardiasis, trichomoniasis, Chagas disease, leishmaniasis, malaria, and toxoplasmosis. AMPs and their analogs demonstrate great potential as therapeutics, with potent and selective activity, when compared with commercially available drugs, and hold the potential to act as new scaffolds for the development of novel anti-protozoal drugs.

Oxidase enzyme genes are differentially expressed during Acanthamoeba castellanii encystment.

Acanthamoeba castellanii, a ubiquitous protozoan, is responsible for significant diseases such as Acanthamoeba keratitis and granulomatous amoebic encephalitis. A crucial survival strategy of A. castellanii involves the formation of highly resistant cysts during adverse conditions. This study delves into the cellular processes underpinning encystment, focusing on gene expression changes related to reactive oxygen species (ROS) balance, with a particular emphasis on mitochondrial processes. Our findings reveal a dynamic response within the mitochondria during encystment, with the downregulation of key enzymes involved in oxidative phosphorylation (COX, AOX, and NADHalt) during the initial 48 h, followed by their overexpression at 72 h. This orchestrated response likely creates a pro-oxidative environment, facilitating encystment. Analysis of other ROS processing enzymes across the cell reveals differential expression patterns. Notably, antioxidant enzymes, such as catalases, glutaredoxins, glutathione S-transferases, peroxiredoxins, and thioredoxins, mirror the mitochondrial trend of downregulation followed by upregulation. Additionally, glycolysis and gluconeogenesis are downregulated during the early stages in order to potentially balance the metabolic requirement of the cyst. Our study underscores the importance of ROS regulation in Acanthamoeba encystment. Understanding these mechanisms offers insights into infection control and identifies potential therapeutic targets. This work contributes to unraveling the complex biology of A. castellanii and may aid in combatting Acanthamoeba-related infections. Further research into ROS and oxidase enzymes is warranted, given the organism's remarkable respiratory versatility.

Necrotizing amebic colitis in an elder patient: an unexpected autopsy finding.

Necrotizing amebic colitis is an uncommon amebiasis complication associated with high mortality. We present a case of necrotizing amebic colitis in an old patient whose diagnosis was revealed at postmortem examination. An 81-year-old man died at home without medical attention. The postmortem examination revealed ulcers involving the entire colon and intestinal perforation. The ulcers were large, geographic, and necrotizing, extending from the cecum to the rectum. The histological examination disclosed the infectious etiology by showing amebic trophozoites at the base of the ulcers. No extra-intestinal lesions were found. No information about previous episodes of dysentery or travel could be obtained. The potential role of aging or drug-causing immunosuppression and the evolution of chronic and latent intestinal infection to a severe and invasive form of amebiasis is discussed. This case reinforces the value of postmortem examination for diagnosing diseases not clinically identified.

Massive pleural empyema secondary to amoebic liver abscess in a child.

BACKGROUND: Pleural empyema secondary to a ruptured amoebic liver abscess is a rare complication in the pediatric population. CASE REPORT: We report the case of a 13-year-old male with right flank abdominal pain, productive cough with foul-smelling sputum, fever, and respiratory distress. Physical examination revealed breathlessness, decreased vesicular murmur in the right hemithorax, abdominal distension, hepatomegaly, and lower limb edema. Laboratory tests revealed mild anemia, leukocytosis without eosinophilia, elevated alkaline phosphatase, hypoalbuminemia, and positive immunoglobulin G antibodies against Entamoeba histolytica in pleural fluid. He required a chest tube and treatment with metronidazole. After 2 months of follow-up, the abscesses disappeared, and the empyema decreased. CONCLUSIONS: Massive pleural empyema secondary to a ruptured liver abscess is a rare complication. The epidemiological link associated with the symptoms and serological tests can help in the diagnosis.

INTRODUCCIÓN: El empiema pleural secundario a ruptura de absceso amebiano hepático es una complicación poco frecuente en la población pediátrica. CASO CLÍNICO: Se reporta el caso de un paciente de sexo masculino de 13 años que presentó dolor abdominal en flanco derecho, tos productiva con esputo de mal olor, fiebre y dificultad respiratoria. Al examen físico se encontró amplexación y murmullo vesicular disminuido en hemitórax derecho, distensión abdominal, hepatomegalia y edema de miembros inferiores. Los resultados del laboratorio evidenciaron anemia leve, leucocitosis sin eosinofilia, elevación de fosfatasa alcalina, hipoalbuminemia y anticuerpos IgG contra Entamoeba histolytica positivo en líquido pleural. Requirió tubo de drenaje torácico y tratamiento con metronidazol. A los dos meses de seguimiento los abscesos desaparecieron y el empiema disminuyó. CONCLUSIONES: El empiema pleural masivo secundario a ruptura de absceso hepático es una complicación poco frecuente. El nexo epidemiológico asociado con la sintomatología y pruebas serológicas pueden ser de ayuda en el diagnóstico.

Apocynin, an NADPH Oxidase Enzyme Inhibitor, Prevents Amebic Liver Abscess in Hamster.

Amebiasis is an intestinal infection caused by Entamoeba histolytica. Amebic liver abscess (ALA) is the most common extraintestinal complication of amebiasis. In animal models of ALA, neutrophils have been shown to be the first cells to come into contact with Entamoeba histolytica during the initial phase of ALA. One of the multiple mechanisms by which neutrophils exhibit amebicidal activity is through reactive oxygen species (ROS) and the enzyme NADPH oxidase (NOX2), which generates and transports electrons to subsequently reduce molecular oxygen into superoxide anion. Previous reports have shown that ROS release in the susceptible animal species (hamster) is mainly stimulated by the pathogen, in turn provoking such an exacerbated inflammatory reaction that it is unable to be controlled and results in the death of the animal model. Apocynin is a natural inhibitor of NADPH oxidase. No information is available on the role of NOX in the evolution of ALA in the hamster, a susceptible model. Our study showed that administration of a selective NADPH oxidase 2 (NOX2) enzyme inhibitor significantly decreases the percentage of ALA, the size of inflammatory foci, the number of neutrophils, and NOX activity indicated by the reduction in superoxide anion (O2-) production. Moreover, in vitro, the apocynin damages amoebae. Our results showed that apocynin administration induces a decrease in the activity of NOX that could favor a decrease in ALA progression.

Antibiotic Prescription Patterns in Children Under 5 Years of Age With Acute Diarrhea in Quito-Ecuador.

BACKGROUND: Diarrheal disease remains a significant cause of child mortality, particularly in regions with limited access to healthcare and sanitation. Inappropriate practices, including unjustified medication prescriptions, pose challenges in the management of acute diarrhea (AD), especially in low- and middle-income countries. OBJECTIVE: This study analyzed antibiotic prescription patterns and assessed compliance with Integrated Management of Childhood Illness (IMCI) guidelines in children under 5 with AD in the Ministry of Public Health (MOPH) Ambulatory Care Centers of Quito city, Ecuador. METHODS: A cross-sectional design was used, collecting electronic health records (EHR) of patients diagnosed with AD from 21 health facilities in District 17D03. A probabilistic and stratified sampling approach was applied. Patient characteristics, prescriber characteristics, treatments, and compliance of IMCI guideline recommendations were evaluated. A stepwise logistic regression analysis examined the association between antibiotic prescription and patient and physician characteristics. RESULTS: A total of 359 children under 5 years of age were included, with 58.77% being girls. 85.24% of the cases of AD were attributed to gastroenteritis and colitis of infectious and unspecified origin. Amebiasis and other protozoal intestinal diseases accounted for 13.37% and 1.11% of the cases, respectively. The completion rates of recording various IMCI parameters varied; parameters such as duration of diarrhea, presence of blood in stool, and evidence of sunken eyes had high completion rates (100%, 100%, and 87.47%, respectively), while parameters like state of consciousness, presence of thirst, and type of diarrhea had low completion rates (0.28%, 0.28%, and 0.84%, respectively). None of the cases had all parameters fully recorded. Antimicrobials were prescribed in 38.72% of the cases. Children aged 3 to 5 years had higher odds of receiving antimicrobial prescription for AD (aOR: 4.42, 95% CI 2.13-9.18, P < .0001) compared to those under 1 year, after adjusting for the number of loose stools per day, gender, and age of the health professional. CONCLUSION: Variations in IMCI guideline compliance were observed, with no cases fully adhering to the guidelines. Antimicrobial prescription rates were notably high, especially among older children. Further research and specialized interventions are necessary to gain comprehensive insight into the factors underlying non-compliance with the IMCI guidelines.

Amoebiasis: Advances in Diagnosis, Treatment, Immunology Features and the Interaction with the Intestinal Ecosystem.

This review of human amoebiasis is based on the most current knowledge of pathogenesis, diagnosis, treatment, and Entamoeba/microbiota interactions. The most relevant findings during this last decade about the Entamoeba parasite and the disease are related to the possibility of culturing trophozoites of different isolates from infected individuals that allowed the characterization of the multiple pathogenic mechanisms of the parasite and the understanding of the host-parasite relationship in the human. Second, the considerable advances in molecular biology and genetics help us to analyze the genome of Entamoeba, their genetic diversity, and the association of specific genotypes with the different amoebic forms of human amoebiasis. Based on this knowledge, culture and/or molecular diagnostic strategies are now available to determine the Entamoeba species and genotype responsible for invasive intestinal or extraintestinal amoebiasis cases. Likewise, the extensive knowledge of the immune response in amoebiasis with the appearance of new technologies made it possible to design diagnostic tools now available worldwide. Finally, the understanding of the interaction between the Entamoeba species and the intestinal microbiota aids the understanding of the ecology of this parasite in the human environment. These relevant findings will be discussed in this review.

The Gal/GalNac lectin as a possible acetylcholine receptor in Entamoeba histolytica.

Entamoeba histolytica (E. histolytica) is a protozoan responsible for intestinal amebiasis in at least 500 million people per year, although only 10% of those infected show severe symptoms. It is known that E. histolytica captures molecules released during the host immune response through membrane receptors that favor its pathogenetic mechanisms for the establishment of amebic invasion. It has been suggested that E. histolytica interacts with acetylcholine (ACh) through its membrane. This promotes the increase of virulence factors and diverse mechanisms carried out by the amoeba to produce damage. The aim of this study is to identify a membrane receptor in E. histolytica trophozoites for ACh. Methods included identification by colocalization for the ACh and Gal/GalNAc lectin binding site by immunofluorescence, western blot, bioinformatic analysis, and quantification of the relative expression of Ras 5 and Rab 7 GTPases by RT-qPCR. Results show that the Gal/GalNAc lectin acts as a possible binding site for ACh and this binding may occur through the 150 kDa intermediate subunit. At the same time, this interaction activates the GTPases, Ras, and Rab, which are involved in the proliferation, and reorganization of the amoebic cytoskeleton and vesicular trafficking. In conclusion, ACh is captured by the parasite, and the interaction promotes the activation of signaling pathways involved in pathogenicity mechanisms, contributing to disease and the establishment of invasive amebiasis.

Amebiasis cutánea por ameba de vida libre, heraldo ignorado de encefalitis letal. Reporte de caso / Free-living cutaneous amebiasis, ignored herald of lethal encephalitis. Case report

Introducción: Las enfermedades por amebas de vida libre (AVL) son poco frecuentes pero con letalidad mayor al 90% cuando comprometen el sistema nerviosos central (SNC). El cuadro clínico puede confundirse con enfermedades más prevalentes. Reporte de caso: Agricultor de 32 años procedente de Poroto-Trujillo-La Libertad-Perú, inicia enfermedad con una placa eritematosa centrofacial que se diagnosticó como tuberculosis cutánea (TBC), sin mejoría pese a recibir esquema completo de quimioterapia antituberculosa. Siete meses después presenta encefalitis severa falleciendo a los tres días de su ingreso al hospital. En la biopsia de piel se encontraron trofozoitos de AVL. Se plantea el diagnóstico de dermatitis cutánea por AVL complicada con encefalitis granulomatosa amebiana (EGA). No se han documentado casos similares en su lugar de procedencia. Conclusión: En el norte del Perú, las placas cutáneas en personas expuestas al suelo o agua estancada, deben considerarse señales de alerta ante la probabilidad de infección por AVL.

ABSTRACT Introduction: Diseases caused by free-living amoebas (FLA) are rare but with a lethality greater than 90% when they affect the central nervous system (CNS). The clinical picture can be confused with more prevalent diseases. Case report: A 32-year-old farmer from Poroto-Trujillo-La Libertad-Peru, started the disease with a central facial erythematous plaque that was diagnosed as cutaneous tuberculosis (CTB), without improvement despite receiving a complete regimen of anti-tuberculous chemotherapy. Seven months later, he presented severe encephalitis and died three days after his admission to the hospital. FLA trophozoites were found in the skin biopsy. A diagnosis of cutaneous dermatitis due to FLA complicated with granulomatous amebic encephalitis (GAE) is proposed. Similar cases have not been documented in his place of origin. Conclusion: In northern Peru, skin plaques in people exposed to the ground or stagnant water should be considered warning signs of the probability of AVL infection.

Lysine Methyltransferase EhPKMT2 Is Involved in the In Vitro Virulence of Entamoeba histolytica.

Lysine methylation, a posttranslational modification catalyzed by protein lysine methyltransferases (PKMTs), is involved in epigenetics and several signaling pathways, including cell growth, cell migration and stress response, which in turn may participate in virulence of protozoa parasites. Entamoeba histolytica, the etiologic agent of human amebiasis, has four PKMTs (EhPKMT1 to EhPKMT4), but their role in parasite biology is unknown. Here, to obtain insight into the role of EhPKMT2, we analyzed its expression level and localization in trophozoites subjected to heat shock and during phagocytosis, two events that are related to amoeba virulence. Moreover, the effect of EhPKMT2 knockdown on those activities and on cell growth, migration and cytopathic effect was investigated. The results indicate that this enzyme participates in all these cellular events, suggesting that it could be a potential target for development of novel therapeutic strategies against amebiasis.

Change in the incidence of intestinal diseases caused by parasitic protozoa in the Mexican population during the period (2015-2019) and its association with environmental and socioeconomic risk factors.

Diarrheal diseases are one of the main health problems worldwide, especially in developing countries with poor health systems, high rates of poverty, and poor nutrition. The main causative agents of diarrheal disease are bacteria, viruses, and parasites; among the latter, the intestinal protozoa Giardia and Entamoeba stand out. In the present work, a observational analysis of the national surveillance data of amebiasis, giardiasis, and other protozoan intestinal infections was carried out. The data issued by the Directorate General of Epidemiology was analyzed to establish its relationship with geography, socioeconomic, and environmental conditions in Mexico during the 2015-2019 period. New cases of amebiasis decreased by 25.03% between 2015 and 2019, while giardiasis and other protozoan intestinal infections remained constant; in all cases, incidence was higher in females than in males, and children under 5 years of age were the most affected. The contribution of environmental conditions (seasonality, temperature, and humidity) and socioeconomic factors in the number of protozoan intestinal infection cases was assessed by a multivariable regression model using a backward selection procedure. Peaks in cases were observed in spring and summer, which are characterized by warm and humid climates. Additionally, states with high humidity and annual average temperature contribute to a notably higher incidence of these parasites, especially annual average temperature, as demonstrated through multivariable linear regression models. Moreover, the majority of these states have the largest population living in poverty with inadequate measures for the distribution, dispensing, and sanitation of water. These data are essential to incidence rate monitoring and focus efforts on eliminating risk factors and improving health programs in Mexico.

In vitro antiparasitic and antibacterial evaluation of organic extracts of Salvadoran flora / Evaluación antiparasitaria y antibacterial in vitro de extractos orgánicos de la flora salvadoreña

Currently, in developing countries, parasitic and bacterial diseases as amebiasis, giardiasis, trichonomiasis, leishmaniasis, trypanosomiasis, tuberculosis, and nocardiasis are a public health problem. The pharmacological treatment for these diseases is not completely effective and causes several side effects in patients. Therefore, the search for new compounds with biological activity is very important to develop new drugs safely and more efficiently. In this study, different organic extracts obtained from thirty-seven species of the Salvadoran flora were evaluated in several in vitro models to determine their potential activity against five protozoa (Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, Leishmania mexicana, and Trypanosoma cruzi) and three bacteria (Acinetobacter baumanni, Mycobacterium tuberculosis, and Nocardia brasiliensis). The results showed the activity of eight extracts with IC50values of less than 100 µg/mL against L. mexicanaand five extracts with MICs values less than <50 µg/mL against M. tuberculosis. Besides, seven plant species showed MICs ≤3.125 µg/mL against N. brasiliensis. Additionally, secondary metabolites (flavonoids and monoterpene oxygenate) previously reported as active were fingerprint by UPLC-MS to establish a potential correlation with the biological activity showed.

Actualmente, en los países en vías de desarrollo, enfermedades parasitarias y bacterianas como la amebiasis, giardiasis, trichonomiasis, leishmaniasis, tripanosomiasis, tuberculosis y nocardiasis son un problema de salud pública. El tratamiento farmacológico de estas enfermedades no es del todo eficaz y provoca varios efectos secundarios en los pacientes. Por lo tanto, la búsqueda de nuevos compuestos con actividad biológica es muy importante para desarrollar nuevos fármacos, seguros y eficaces. En este estudio se evaluaron diferentes extractos orgánicos obtenidos de treinta y siete especies de la flora salvadoreña en varios modelos in vitro para determinar su actividad potencial contra cinco parásitos (Entamoeba histolytica, Giardia lamblia, Trichomonas vaginalis, Leishmania mexicana y Trypanosoma cruzi) y tres bacterias (Acinetobacter baumanni, Mycobacterium tuberculosis y Nocardia brasiliensis). Los resultados mostraron la actividad de ocho extractos con valores de CI50 menores a 100 µg/mL contra L. mexicana y cinco extractos con valores de CIMs <50 µg/mL contra M. tuberculosis. Además, siete especies de plantas presentaron CIM ≤3,125 µg/mL frente a N. brasilienses. Finalmente, los metabolitos secundarios (flavonoides y monoterpenos oxigenados) previamente reportados como activos fueron determinados por UPLC-MS para establecer una posible correlación con la actividad biológica mostrada.