Electron microscopic study of the morphology and morphogenesis of virus of hemorrhagic fever with renal syndrome

Ellipticine derivative NSC 338258 represents a potential new antineoplastic agent for the treatment of multiple myeloma

High-risk multiple myeloma can be correlated with amplification and overexpression of the cell cycle regulator CKS1B. Herein, we used the COMPARE algorithm to correlate high expression of CKS1B mRNA in the NCI-60 cell line panel with the concentration causing 50% growth inhibition (GI(50)) of >40,000 synthetic compounds. This led to the identification of NSC 338258 (EPED3), a highly stable, hydrophilic derivative of the plant alkaloid ellipticine. In vitro, this synthetic anticancer compound exhibits dramatic cytotoxic activity against myeloma cells grown in suspension or in coculture with stromal cells. EPED3-induced cell cycle arrest and an apoptotic progression that appear to be a consequence of the instantaneous effect of the drug on cytoplasmic organelles, particularly mitochondria. Disruption of mitochondria and cytoplasmic distribution of cytochrome c initiated the intracellular proteolytic cascade through the intrinsic apoptotic pathway. EPED3 is able to induce apoptosis in myeloma cells with de novo or acquired resistance to commonly administered antimyeloma agents. Collectively, our data suggest that EPED3 targets mitochondrial function to rapidly deplete chemical energy and initiate apoptosis in myeloma cells at nanomolar concentrations while leaving stromal cells unharmed.

Liver involvement in epidemic haemorrhagic fever: in situ hybridization, immunohistochemical and pathological studies

In the present study, liver biopsy specimens from 37 patients with epidemic haemorrhagic fever (EHF) were investigated by using light and electron microscopy, immunohistochemistry for the EHF virus envelope protein G2 and in situ hybridization (ISH) for EHF viral RNA. Immunostaining and in situ hybridization were both positive, and a few of the aetiological agents, the EHF virus (EHFV) particles, were found individually within the dilated Golgi cisternae and vesicles, and the dilated rough endoplasmic reticulum of the hepatocyte. The pathological alterations of the liver cells infected with EHFV were: hepatocellular degeneration, cytoplasmic vacuolation, and spotty necrosis; moreover, zonal necrosis was present and adjacent to the narrowed and occluded sinusoids. In degenerated and spotty necrotic cells, the positive signals from of ISH for EHFV RNA and those from immunostaining for the virus protein were both stronger than those in the zonal liver cell necrosis area. The results showed that hepatocellular degeneration and spotty necrosis might be directly related to the virus and its duplication inside the liver cells, while the zonal necrosis was ischaemic and thought to be caused by microcirculation dysfunction.

Pathological studies on central nervous tissues of rats infected with Rattus serotype hantavirus (SR-11 strain)

Newborn rats inoculated intraperitoneally with a hantavirus strain (SR-11) developed neurological signs such as ataxia and limb paralysis. The main histological lesions were scattered and multiple neuronal degeneration and necrosis with eosinophilic cytoplasmic inclusion bodies (CIB) in the brain, spinal cord and ganglia. Immunohistochemically, the viral antigen was detected in neurons, capillary endothelial and glial cells throughout the nervous tissue and CIB were identified as consisting of hantaviral antigen (nucleocapsid protein). Ultrastructurally, CIB in the neurons consisted of an accumulation of granular or filamentous materials, or both. They were seen near a well-developed Golgi apparatus and associated with well-developed rough endoplasmic reticulum and increased numbers of ribosomes. The present results suggested that this virus strain was highly infective in neurons of the newborn rats and that excess production of viral antigen which accumulated as CIB resulted in the neuronal changes.