Clinical and laboratory aspects of a trichinellosis outbreak in Izmir, Turkey

Epidemiological, clinical and laboratory data were collected during an outbreak of trichinellosis, which occurred in Izmir, Turkey, between January and March 2004. The source of the infection was raw meatballs made with a mixture of uncooked beef and pork. Of 474 persons who were admitted at the Ataturk Training and Research Hospital during this period with a history of raw meatball consumption, the diagnosis of trichinellosis was confirmed for 154 (32.5%, 87 males and 67 females; mean age 31 years, range 6-67 years). Among persons with a confirmed diagnosis, 79% had myalgia, 77% weakness and malaise, 63% arthralgia, 40% jaw pain, 68% fever, 63% periorbital and/or facial oedema, 49% oedema at the trunk and limb, 42% abdominal pain, 40% nausea and vomiting, 28% diarrhoea, 23% subconjunctival haemorrhage, 25% macular or petechial rash, 4% subungual haemorrhage, 15% cardiac complaints and 0.2% neurological complaints. Nine patients (5.8%) were hospitalised due to severe myalgia (n = 2), high fever (n = 3), neurological manifestations (n = 1), thrombophlebitis (n = 2) and palmar erythema (n = 1). Eosinophilia was present in 88% of the confirmed cases at the admission. Elevated levels of serum creatine phosphokinase, lactic dehydrogenase and aspartate aminotransferase were detected in 72%, 70% and 16% of the confirmed cases, respectively. The seroconversion occurred in most of the infected people between the 4th and 6th weeks after the infection. All of the confirmed cases were treated with mebendazole. People with severe symptoms were treated also with prednisolone (60 mg/day for three days) and those with a moderately severe clinical pattern received a non-steroid anti-inflammatory drug (naproxen sodium, 550 mg/day). All confirmed cases recovered without any clinical sequela.     

miR-376b controls starvation and mTOR inhibition-related autophagy by targeting ATG4C and BECN1

Macroautophagy (autophagy) is the major intracellular degradation pathway for long-lived proteins and organelles. It helps the cell to survive a spectrum of stressful conditions including starvation, growth factor deprivation and misfolded protein accumulation. Moreover, abnormalities of autophagy play a role in major health problems including cancer and neurodegenerative diseases. Yet, mechanisms controlling autophagic activity are not fully understood. Here, we describe hsa-miR-376b (miR-376b) as a new microRNA (miRNA) regulating autophagy. We showed that miR-376b expression attenuated starvation- and rapamycin-induced autophagy in MCF-7 and Huh-7 cells. We discovered autophagy proteins ATG4C and BECN1 (Beclin 1) as cellular targets of miR-376b. Indeed, upon miRNA overexpression, both mRNA and protein levels of ATG4C and BECN1 were decreased. miR-376b target sequences were present in the 3' UTR of ATG4C and BECN1 mRNAs and introduction of mutations abolished their miR-376b responsiveness. Antagomir-mediated inactivation of the endogenous miR-376b led to an increase in ATG4C and BECN1 levels. Therefore, miR-376b controls autophagy by directly regulating intracellular levels of two key autophagy proteins, ATG4C and BECN1.     

Neutrophil elastase, proteinase 3 and cathepsin G: physicochemical properties, activity and physiopathological functions

Polymorphonuclear neutrophils form a primary line of defense against bacterial infections using complementary oxidative and non-oxidative pathways to destroy phagocytized pathogens. The three serine proteases elastase, proteinase 3 and cathepsin G, are major components of the neutrophil primary granules that participate in the non-oxidative pathway of intracellular pathogen destruction. Neutrophil activation and degranulation results in the release of these proteases into the extracellular medium as proteolytically active enzymes, part of them remaining exposed at the cell surface. Extracellular neutrophil serine proteases also help kill bacteria and are involved in the degradation of extracellular matrix components during acute and chronic inflammation. But they are also important as specific regulators of the immune response, controlling cellular signaling through the processing of chemokines, modulating the cytokine network, and activating specific cell surface receptors. Neutrophil serine proteases are also involved in the pathogenicity of a variety of human diseases. This review focuses on the structural and functional properties of these proteases that may explain their specific biological roles, and facilitate their use as molecular targets for new therapeutic strategies.