The impact of work-related risk on nurses during the SARS outbreak in Hong Kong

Severe acute respiratory syndrome (SARS) is a highly infectious disease, with high potential for transmission to close contacts, particularly among healthcare workers. This is the first systematic study investigating hospital nurses' physical and psychological health status and the kinds of healthcare used-stratified by the level of contact with SARS patients-during the 2003 outbreak in Hong Kong. Nurses in moderate-risk areas appeared to have more stress symptoms than those working in high-risk areas. It is essential to design hospital support systems and occupational health policy to promote the psychological well-being of nurses during future outbreaks of emerging infections.     

Peripapillary glial cells in the chick retina: A special glial cell type expressing astrocyte, radial glia, neuron, and oligodendrocyte markers throughout development

Peripapillary glial cells of the chick are a special type of glia, not only because of their position, forming a boundary between the retina on one side and the optic nerve head (ONH) and the pecten on the other, but also because although they have the same orientation and similar shape as the retinal Müller cell (a type of radial glia) and express common markers for these cells and astrocytes, they do not express glutamine synthetase (GS) or carbonic anhydrase C (CA-C), enzymes intensely expressed by Müller cells and astrocytes. In this study, we present further molecular characterization of these cells, using immunohistochemistry techniques. We show that peripapillary glial cells express a novel neuron antigen, 3BA8, that in the adult retina is located only in one neuron type (the amacrine cell) and in the inner plexiform layer (IPL). They also express an antigen specific to myelin and oligodendrocytes, MOSP, and a glial antigen, 3CB2, expressed by radial glia and astrocytes throughout the CNS. The study of the developmental expression of these three antigens in the peripapillary glial cell territory shows different spatiotemporal labeling patterns: 3CB2 and 3BA8 are expressed much earlier (embryonic days E3 and E5, respectively) than MOSP (E12), and during a developmental window (E6-E10) 3BA8 labels the peripapillary glial cells intensely and does not label the ONH or the optic nerve (ON), which are labeled later. The expression of 3CB2 is much more intense in the peripapillary glial cells than in Müller cells from early stages of development up to E16, and the expression of MOSP starts earlier in the peripapillary glial cells than in the Müller cells and is maintained with much higher intensity in the peripapillary glial cells throughout development. These findings show that Müller and peripapillary glial cells follow independent courses of differentiation, which together with the fact that the peripapillary glial cells express molecules typical of neurons, oligodendrocytes, radial glia, and astrocytes are evidence that peripapillary glial cells are a unique type of glia in the CNS.     

Domino as a bridge to definitive liver transplantation in a neonate

An interim liver transplant was used to extend survival in a neonate. This was accomplished by the initial transplant of a left-lateral segment of a metabolically abnormal liver obtained from a 7-yr-old patient with primary oxalosis. This bridging strategy was required because our neonatal patient was dying of fulminant hepatic failure caused by hepatic vein thrombosis and a small liver or liver segment could not be found. Although problems with hyperoxaluria were encountered in the neonate post-transplant, the interim liver transplant enabled the baby to survive and grow until the age of 4 months. At that time, a definitive transplant was performed using the left-lateral segment of his mother's liver. This case represents the first reported use of a pediatric domino transplant where a metabolically abnormal liver was used to allow sufficient growth to permit a definitive liver transplantation.     

Humor and health in early adolescents: perceived field motion as a mediating variable

The purpose of this study was to test a mediational model, developed within the science of unitary human beings, by examining the relationship between humor and eudaimonistic health conception in early adolescents and by examining the extent to which perceived field motion mediated this relationship. The sample consisted of 136 adolescents, aged 12 to 14, who responded to instruments measuring humor, perceived field motion, and eudaimonistic health conception in classroom settings. Correlational analysis supported the three hypothesized relationships. Regression analyses indicated that perceived field motion was one mediator of the relationship between humor and eudaimonistic health conception.     

Ras-dependent oncolysis with an adenovirus VAI mutant

Adenovirus synthesize proteins that interact with oncogene and tumor suppressor gene products to set the cell for virus replication. Mutant viruses defective in these functions replicate selectively in cancer cells and represent new tools to treat cancer. We report a selectivity strategy based on deletions of adenovirus Virus-Associated (VA) RNAs. In normal cells, these RNAs are necessary for virus replication because they inactivate the RNA-dependent protein kinase protein kinase R, a kinase that otherwise would block protein translation in response to infection. However, downstream effectors of Ras can also inactivate protein kinase R, and therefore, the need for VA RNA genes should be bypassed in cells with an active Ras pathway. We demonstrate here that a VAI RNA mutant presents a Ras-dependent replication and can be used for oncolytic virotherapy of pancreatic tumors.     

Fasciola hepatica: lithogenic capacity in experimentally infested rats and chemical determination of the main stone components

A study was done of the possible association between the development of common bile-duct stones and the presence of worms in rats experimentally infected with Fasciola hepatica. A total of 157 rats were individually infected with 20 metacercariae, and another 40 animals served as controls. The rats were dissected at 100, 200, 300, and 400 days postinfection (p.i.). A significant association was observed between the observation of stones and the presence of F. hepatica adults. The global frequency of bile-duct lithiasis in the parasitized rats was 22%, with a significantly lower incidence being observed in the younger group (100 days p.i.). Different analytical techniques were used to determine the main stone components. Energy-dispersive X-ray microanalysis showed calcium to be the main component in all cases (82–94%). Scanning electron microscopy, nuclear magnetic resonance ([¹H]- and [¹³C]-NMR), and mass spectrometry revealed the predominance of palmitic (C-16) and stearic (C-18) acid. Received: 17 December 1999 / Accepted: 23 December 1999