Morphology of Echinococcus granulosus protoscolex / Morfología de los Protoescolex de echinococcus granulosus

SUMMARY: Echinococcus granulosus (E. granulosus), is a tapeworm that spreads between intermediate and definitive hosts through the ingestion of fecal matter contaminated with the parasite's eggs. The life cycle consists of differentiation from eggs to oncospheres to embryos, which eventually form cysts in organs like the liver, lungs and others. Within these cysts are protoscolices, an intermediate stage of the parasite which develop into adult tapeworms once they infect their definitive hosts. When these hydatid cysts form in humans, it is known as Cystic Echinococcosis (CE). This disease is treated through surgical excision of the cysts and or chemotherapy with benzimidazole compounds. Understanding the morphology of the intermediate developmental stage of E. granulosus, protoscolex stage, can allow researchers to identify defining structural changes and protein functions that could be used to develop treatment modalities for CE. Unique characteristics in the tegumental surface during the protoescolex stage and proteins associated with cyst fertility have all been identified in previous research studies and bring researchers closer to understanding the underlying mechanisms of E. granulosus development, and consequently, means to disrupt it to achieve better control of the disease.

El Echinococcus granulosus (E. granulosus), es un cestodo que se propaga entre huéspedes intermedios y definitivos a través de la ingestión de materia fecal contaminada con los huevos del parásito. El ciclo de vida consiste en la diferenciación de huevos a oncosferas y embriones, que finalmente forman quistes en órganos como el hígado, los pulmones y otros. Dentro de estos quistes hay protoescólices, una etapa intermedia del parásito que se convierte en su forma adulta (tenia), una vez que infectan a sus huéspedes definitivos. Cuando estos quistes hidatídicos se desarrollan en seres humanos, se les conoce como equinococosis quística (EC). Esta enfermedad se trata mediante la extirpación quirúrgica de los quistes o la quimioterapia con compuestos benzimidazólicos. La comprensión de la morfología de la etapa de desarrollo intermedia del E. granulosus y la etapa de protosclex, puede permitir a los investigadores identificar cambios estructurales definidos y funciones de proteínas que podrían usarse para desarrollar modalidades de tratamiento para la CE. Las características únicas en la superficie tegumentaria durante la etapa de protoescolex y las proteínas asociadas con la fertilidad del quiste se han identificado en estudios de investigación anteriores y acercan a los investigadores a la comprensión de los mecanismos subyacentes del desarrollo del E. granulosus y, en consecuencia, los medios para interrumpirlo para lograr un mejor control de la enfermedad.

Death switch for gene therapy: application to erythropoietin transgene expression

The effectiveness of the caspase-9-based artificial "death switch" as a safety measure for gene therapy based on the erythropoietin (Epo) hormone was tested in vitro and in vivo using the chemical inducer of dimerization, AP20187. Plasmids encoding the dimeric murine Epo, the tetracycline-controlled transactivator and inducible caspase 9 (ptet-mEpoD, ptet-tTAk and pSH1/Sn-E-Fv’-Fvls-casp9-E, respectively) were used in this study. AP20187 induced apoptosis of iCasp9-modified C2C12 myoblasts. In vivo, two groups of male C57BI/6 mice, 8-12 weeks old, were injected intramuscularly with 5 µg/50 g ptet-mEpoD and 0.5 µg/50 g ptet-tTAk. There were 20 animals in group 1 and 36 animals in group 2. Animals from group 2 were also injected with the 6 µg/50 g iCasp9 plasmid. Seventy percent of the animals showed an increase in hematocrit of more than 65 percent for more than 15 weeks. AP20187 administration significantly reduced hematocrit and plasma Epo levels in 30 percent of the animals belonging to group 2. TUNEL-positive cells were detected in the muscle of at least 50 percent of the animals treated with AP20187. Doxycycline administration was efficient in controlling Epo secretion in both groups. We conclude that inducible caspase 9 did not interfere with gene transfer, gene expression or tetracycline control and may be used as a safety mechanism for gene therapy. However, more studies are necessary to improve the efficacy of this technique, for example, the use of lentivirus vector.

Investigation of the child with interstitial lung disease.

Many disorders can affect the pulmonary interstitium in children. Although individual interstitial lung diseases are rare, the range of conditions encountered is wide. Interstitial disease is also seen increasingly as a consequence of the treatment of children having other primary problems including cancer, immunodeficiency and haemotological diseases, as well as in recipients of solid organ and bone marrow transplants. The management and prognosis of individual conditions is highly variable, thus it is essential to search for a precise diagnosis in every patient. High resolution computerised tomography (HRCT) and other less invasive investigations may be helpful in the management of patients. However, it is unusual to be able to make a firm diagnosis without a lung biopsy.