Markers for trans-Golgi Membranes and the Intermediate Compartment Localize to Induced Membranes with Distinct Replication Functions in Flavivirus-Infected Cells

Replication of the flavivirus Kunjin virus is associated with virus-induced membrane structures within the cytoplasm of infected cells; these membranes appear as packets of vesicles associated with the sites of viral RNA synthesis and as convoluted membranes (CM) and paracrystalline arrays (PC) containing the components of the virus-specified protease (E. G. Westaway, J. M. Mackenzie, M. T. Kenney, M. K. Jones, and A. A. Khromykh, J. Virol. 71:6650-6661, 1997). To determine the cellular origins of these membrane structures, we compared the immunolabelling patterns of several cell markers in relation to these sites by immunofluorescence and immunoelectron microscopy. A marker for the trans-Golgi membranes and the trans-Golgi network, 1,4-galactosyltransferase (GalT), was redistributed to large foci in the cytoplasm of Kunjin virus-infected cells, partially coincident with immunofluorescent foci associated with the putative sites of viral RNA synthesis. As determined by immunoelectron microscopy, the induced vesicle packets contained GalT, whereas the CM and PC contained a specific protein marker for the intermediate compartment (ERGIC53). A further indicator of the role of cellular organelles in their biogenesis was the observation that the Golgi apparatus-disrupting agent brefeldin A prevented further development of immunofluorescent foci of induced membranes if added before the end of the latent period but that once formed, these membrane foci were resistant to brefeldin A dispersion. Reticulum membranes emanating from the induced CM and PC were also labelled with the rough endoplasmic reticulum marker anti-protein disulfide isomerase and were obviously redistributed during infection. This is the first report identifying trans-Golgi membranes and the intermediate compartment as the apparent sources of the flavivirus-induced membranes involved in events of replication.     

Genome Sequence of Staphylococcus epidermidis Strain AU12-03, Isolated from an Intravascular Catheter

In recent years, Staphylococcus epidermidis has become a major nosocomial pathogen and the most common cause of intravascular catheter-related bacteremia, which can increase morbidity and mortality and significantly affect patient recovery. We report a draft genome sequence of Staphylococcus epidermidis AU12-03, isolated from an intravascular catheter tip.     

Predator detection and avoidance by starlings under differing scenarios of predation risk

Practically all animals must find food while avoiding predators.An individual's perception of predation risk may depend on manyfactors, such as distance to refuge and group size, but it isunclear whether individuals respond to different factors ina similar manner. We tested whether flocks of foraging starlingsresponded in the same way to an increased perception of predationrisk by assessing three factors: (1) neighbor distances, (2)habitat obstruction, and (3) recent exposure to a predator.We found that in all three scenarios of increased risk, starlingsreduced their interscan intervals (food-searching bouts), whichincreased the frequency of their vigilance periods. We thenexamined how one of these factors, habitat obstruction, affectedescape speed by simulating an attack with a model predator.Starlings were slower to respond in visually obstructed habitats(long grass swards) and slower when they had their head downin obstructed habitats than when they had their head down inopen habitats. In addition, reaction times were quicker whenstarlings could employ their peripheral fields of vision. Ourresults demonstrate that different sources of increased riskcan generate similar behavioral responses within a species.The degree of visibility in the physical and social environmentaffects both the actual and perceived risk of predation.     

Effects of applications of municipal compost on uptake of copper,zinc and boron by garden vegetables

Summary Municipal compost applied to soils in plot experiments with cabbages, lettuces, beans, potatoes and peas in three successive years (25–100 tonnes per hectare) has produced significant enhancement of available soil Cu, Zn and B in each year. Associated significant increases in uptake were as follows: Cu, Zn and B with lettuces and beans, Zn and B with potatoes and B with peas. No significant increases in uptake of any of these elements was obtained in two experiments with cabbages.Compost treatment was associated with severe phytotoxic effects in the experiment with beans and with yield responses in the experiments with peas and potatoes. re]19721116     

Prostaglandin-induced Abortion: Assessment of Operative Complications and Early Morbidity

A total of 626 patients undergoing a prostaglandin-induced abortion, the majority in the second trimester, have been analysed for complications occurring during inpatient treatment. Of the last 155 consecutive patients 143 were critically assessed six to eight weeks after abortion for morbidity occurring during their early recovery period.Blood loss of 250 ml or more occurred in 68 patients, pyrexia in 34, pelvic infection in three, and readmission in 14 of the 626 patients studied, and a transfusion was required in eight.Bleeding after abortion stopped within six weeks in all 143 of the 155 consecutive patients assessed but three required readmission for uterine curettage. Menstruation was re-established within six weeks of abortion in 106 patients.The incidence of operative morbidity was similar to that reported for first trimester abortion and better than that in most reported series of second trimester abortions.     

RECENT APPEARANCE OF CYLINDROSPEMOPSIS (CYANOBACTEIUA) IN FIVE HYPEREUTROPHIC FLORIDA LAKES1

Observations of historical and recent phytoplankton samples from five hypereutrophic Florida lakes indicate that nitrogen-fixing cyanobacteria in the genus Cylindrospermopsis Seenayya et Subba Raju have entered these water-bodies sometime in the last 30 years. Cylindrospermopsis forms a year-round bloom in one of the five lakes, dominates seasonally in another, and is at least at times an important component of the phytoplankton community in the remaining three. The increase in abundance of Cylindrospermopsis in Florida lakes could have implications for water management.     

Growth Phase-Dependent Regulation of Vsr Endonuclease May Contribute to 5-Methylcytosine Mutational Hot Spots in Escherichia coli

Using rabbit polyclonal antibodies, we have shown that the Dcm cytosine methylase of Escherichia coli is maintained at a constant level during cell growth, while Vsr endonuclease levels are growth phase dependent. Decreased production of Vsr relative to Dcm during the log phase may contribute substantially to the mutability of 5-methylcytosine.     

Role of NK Cell Subsets in Organ-Specific Murine Melanoma Metastasis

Tumor metastasis plays a major role in the morbidity and mortality of cancer patients. Among solid tumors that undergo metastasis, there is often a predilection to metastasize to a particular organ with, for example, prostate cancer preferentially metastasizing to bones and colon cancer preferentially metastasizing to the liver. Although many factors are thought to be important in establishing permissiveness for metastasis, the reasons for organ-specific predilection of each tumor are not understood. Using a B16 murine melanoma model, we tested the hypothesis that organ-specific NK cell subsets play a critical role in organ-specific metastasis of this tumor. Melanoma cells, given intravenously, readily colonized the lungs but not the liver. NK cell depletion (either iatrogenically or by using genetically targeted mice) resulted in substantial hepatic metastasis. Analysis of NK cell subsets, defined by the differential expression of a combination of CD27 and CD11b, indicated a significant difference in the distribution of NK cell subsets in the lung and liver with the mature subset being dominant in the lung and the immature subset being dominant in the liver. Several experimental approaches, including adoptive transfer, clearly indicated that the immature hepatic NK cell subset, CD27+ CD11b–, was protective against liver metastasis; this subset mediated its protection by a perforin-dependent cytotoxic mechanism. In contrast, the more mature NK cell subsets were more efficient at reducing pulmonary tumor load. These data indicate that organ-specific immune responses may play a pivotal role in determining the permissiveness of a given organ for the establishment of a metastatic niche.