Giardia intestinalis and its endomembrane system.

Giardia intestinalis has unique characteristics, even in the absence of certain organelles. For instance, Golgi and mitochondria are not found. On the other hand, there is a network of peripheral vacuoles (PVs) and mitosomes. The endoplasmic reticulum (ER), nuclear membrane, peroxisomes, and lipid bodies are present. The peripheral vacuole system seems to play several simultaneous roles. It is involved in the endocytic activity of the trophozoite but also has characteristics of early and late endosomes and even lysosomes, establishing a connection with the ER. Some of the PVs contain small vesicles, acting as multivesicular bodies, including the release of exosomes. The mitosomes are surrounded by two membranes, divide during mitosis, and are distributed throughout the cell. They do not contain DNA, enzymes involved in the citric acid cycle, respiratory chain, or ATP synthesis. However, they contain the iron-sulfur complex and transporters as TOM and TIM. Some mitosomes are linked to flagellar axonemes through a fibrillar connection. During encystation, two types of larger cytoplasmic vesicles appear. One originating from the ER contains the cyst wall proteins. Another contains carbohydrates. Both migrate to the cell periphery and fuse with plasma membrane secreting their contents to give rise to the cell wall.

Activity of Thioallyl Compounds From Garlic Against Giardia duodenalis Trophozoites and in Experimental Giardiasis.

Fresh aqueous extracts (AGEs) and several thioallyl compounds (TACs) from garlic have an important antimicrobial activity that likely involves their interaction with exposed thiol groups at single aminoacids or target proteins. Since these groups are present in Giardia duodenalis trophozoites, in this work we evaluated the anti-giardial activity of AGE and several garlic's TACs. In vitro susceptibility assays showed that AGE affected trophozoite viability initially by a mechanism impairing cell integrity and oxidoreductase activities while diesterase activities were abrogated at higher AGE concentrations. The giardicidal activities of seven TACs were related to the molecular descriptor HOMO (Highest Occupied Molecular Orbital) energy and with their capacity to modify the -SH groups exposed in giardial proteins. Interestingly, the activity of several cysteine proteases in trophozoite lysates was inhibited by representative TACs as well as the cytopathic effect of the virulence factor giardipain-1. Of these, allicin showed the highest anti-giardial activity, the lower HOMO value, the highest thiol-modifying activity and the greatest inhibition of cysteine proteases. Allicin had a cytolytic mechanism in trophozoites with subsequent impairment of diesterase and oxidoreductase activities in a similar way to AGE. In addition, by electron microscopy a marked destruction of plasma membrane and endomembranes was observed in allicin-treated trophozoites while cytoskeletal elements were not affected. In further flow cytometry analyses pro-apoptotic effects of allicin concomitant to partial cell cycle arrest at G2 phase with the absence of oxidative stress were observed. In experimental infections of gerbils, the intragastric administration of AGE or allicin decreased parasite numbers and eliminated trophozoites in experimentally infected animals, respectively. These data suggest a potential use of TACs from garlic against G. duodenalis and in the treatment of giardiasis along with their additional benefits in the host's health.

Achados hematológicos de cães positivos para babesiose em Fortaleza, Ceará / Hematologic findings in dogs with positive to babesiosis in Fortaleza, Ceará

Canine babesiosis is an endemic parasitic disease in Brazil, caused by an intraerythrocytic protozoa (Babesia canis or Babesia gibsoni). Despite offering unspecific results, the complete blood count may aid in the diagnosis of the disease. Thus, the aim of this study is to evaluate the hematological changes observed in diagnosed with babesiosis. In this study, the most frequent hematological findings in dogs with babesiosis were anemia, thrombocytopenia, hypoproteinemia, and eosinopenia.

Achados hematológicos de cães positivos para babesiose em Fortaleza, Ceará / Hematologic findings in dogs with positive to babesiosis in Fortaleza, Ceará

Canine babesiosis is an endemic parasitic disease in Brazil, caused by an intraerythrocytic protozoa (Babesia canis or Babesia gibsoni). Despite offering unspecific results, the complete blood count may aid in the diagnosis of the disease. Thus, the aim of this study is to evaluate the hematological changes observed in diagnosed with babesiosis. In this study, the most frequent hematological findings in dogs with babesiosis were anemia, thrombocytopenia, hypoproteinemia, and eosinopenia.(AU)

Perforación intestinal secundaria a amebiasis / Amebiasis intestinal perforation secondary

La amebiasis intestinal es una enfermedad frecuente en países en desarrollo, que es común en regiones tropicales y subtropicales, así como en regiones con servicios sanitarios deficientes. Presentamos el caso de un paciente de 74 años de edad, sexo masculino, originario y residente de la ciudad de Guatemala, quién cursó una diarrea y dolor abdominal. Fue intervenido quirúrgicamente por abdomen agudo, con resección intestinal extensa por perforaciones. En el estudio de anatomía patológica se realizó el diagnóstico de colitis amebiana con perforaciones y peritonitis.

Intestinal amoebiasis is a disease common indeveloping countries, which is common in tropicaland subtropical regions, as well as in regions withpoor sanitation. We report the case of a 74-year-oldmale, resident of Guatemala City, who presented withdiarrhea and abdominal pain. He had a laparatomy foracute abdomen, undergoing wide intestinal resectiondue to perforations. The pathology diag-nosis wasamoebic colitis with perforations and peritonitis.