The objective of this study was to evaluate the prevalence and dissemination of human astroviruses (HAstV) in the environment by analyzing urban sewage samples from a wastewater treatment plant in the city of Rio de Janeiro, Brazil. A one-year study was performed with a total of 48 raw and treated sewage composite samples, which were collected biweekly from an activated sludge plant. Virus part...

The smectic-A to nematic ~Sm-A–N! transition was studied confined to the randomly interconnected voids of Millipore filters via a high resolution calorimetry. The heat capacity peaks evolve from sharp and prominent to broad and small depending on void size. The random confinement drives the heat capacity critical exponent from the bulk value towards zero, indicating a confinement-induced decoup...

Mitochondrial RNA (mtRNA) was synthesized from purine and pyrimidine nucleosides in coupling with oxidative phosphorylation using isolated mitochondria. The in vivo synthesized mtRNA was adenine-uracil rich and sedimented at about 20 S by sucrose density gradient centrifugation. A major part of the newly synthesized mtRNA was shown to be poly (A)-containing RNA by the resistance to the digestio...

Survival of Aeromonas salmonicida in natural (non-sterile) seawater, as determined from colony counts on marine agar, was found to be influenced by the presence of potentially inhibitory organisms, i.e., Acinetobacter, Aeromonas hydrophila, Chromobacterium, Escherichia coli, Flavobacterium and Pseudomonas, and their metabolites. Yet, samples, thought to be devoid of culturable A. salmonicida, w...

Medium from a stationary phase culture of axenically grown D. discoideum cells contains an inhibitor of cohesion of log phase cells. The inhibitor is a heat-stable, low molecular weight substance. Its biological effects include inhibition of cohesion of aggregation-competent cells, of cells of other slime mould species, the blocking of development on Millipore filters and a reduction in adhesiv...

Fluid and electrolyte transport by epithelial cells in vitro can be recognized by the ability of cultured cells to form domes and by the electrical properties of monolayer cultures. Pulmonary alveolar epithelial cells are thought to be partially responsible for fluid movement in the fetal lung, but their role in electrolyte transport in the adult lung is not known. We isolated alveolar type II ...

The Labscale tangential flow diafiltration system in conjunction with polyethersulfone Biomax filters (both purchased from Millipore Inc.) were used in the following studies: (1) A crucial step in the preparation of polyhemoglobin (polyHb) is the removal of tetrameric hemoglobin (Hb), which can cause adverse side-effects. The efficiency for this depends on the integrity of the 100kDa filters. T...

Pfizer selective enterococcus (PSE) and KF agars were compared for their recovery of fecal streptococci from sewage effluent on membrane filters. The results showed that PSE agar is highly selective for the enterococci. The tan color resulting from esculin hydrolysis, which was not always visible on the surfaces of the colonies, is not considered a necessary differential characteristic on PSE a...

A number of parameters affecting the adsorption of rRNA and poly(A)-containing RNA to Millipore filters were investigated separately. Binding of both types of RNA to the filter was dependent on the concentration of RNA, pH and Mg2+ concentration of the reaction mixture. Both types of RNA bound to the filter optimally at slightly acid pH values. The binding of poly(A)-containing RNA to the filte...