Molecular analysis of the PHO81 gene of Saccharomyces cerevisiae.

The PHO81 gene product is a positive regulatory factor required for the synthesis of the phosphate repressible acid phosphatase (encoded by the PHO5 gene) in Saccharomyces cerevisiae. Genetic analysis has suggested that PHO81 may be the signal acceptor molecule; however, the biochemical function of the PHO81 gene product is not known. We have cloned the PHO81 gene and sequenced the promoter. A PHO81-LacZ fusion was shown to be a valid reporter since its expression is regulated by the level of inorganic phosphate and is controlled by the same regulatory factors that regulate PHO5 expression. To elucidate the mechanism by which PHO81 functions, we have isolated and cloned dominant mutations in the PHO81 gene which confer constitutive synthesis of acid phosphatase. We have demonstrated that overexpression of the negative regulatory factor, PHO80, but not the negative regulatory factor PHO85, partially blocks the constitutive acid phosphatase synthesis in a strain containing a dominant constitutive allele of PHO81. This suggests that PHO81 may function by interacting with PHO80 or that these molecules compete for the same target.     

Loss of identity in nineteenth-century Norway: Oslo's House of Correction

In Norway, there was considerable overlap between the poor house, the workhouse, and correctional facilities. An assemblage of human skeletal remains from Oslo's House of Correction cemetery, largely comprised of individuals disturbed during municipal development in 1989, consists of c. 314 individuals who died as inmates or residents; many were disabled or elderly. Although names were recorded at death, the cemetery lacked grave markers or a map, with no expectation families might one day reclaim relatives. All remains have been aged and sexed anthropologically, with samples collected for biomolecular investigations. Despite extensive archival documentation, including names recorded in the House of Correction church book, their identities are shrouded by time. Observations of age, injury, and disease can suggest why inmates ended up in the House of Correction cemetery. But there, individual stories end and identities are lost.     

Soft tissue response to Proplast: quantitation of scar ingrowth

We compared, histologically and biochemically, the effects of blood pretreatment vs. no pretreatment on the ingrowth of scar into subcutaneously implanted blocks of Proplast in rats. No significant differences were found.     

Acetaldehyde (CH3CHO) production in rodent lung after exposure to metal-rich particles.

Epidemiological reports demonstrate an association between increased human morbidity and mortality with exposure to air pollution particulate matter (PM). Metal-catalyzed oxidative stress has been postulated to contribute to lung injury in response to PM exposure. We studied the effects of residual oil fly ash (ROFA), a component of ambient air PM, on the formation of lung carbonyls that are indicators of lipid peroxidation. Rats were instilled intratracheally with ROFA (62.5-1000 micrograms) and underwent lung lavage. Lavage fluid carbonyls were derivatized with 2,4-dinitrophenylhydrazine, and measured by high performance liquid chromatography with UV detection. Dose-dependent increases in a peak that eluted with the same retention time as the acetaldehyde (CH3CHO) derivative was observed in rats treated with ROFA 15 min after instillation (up to 25-fold greater than saline treated controls). The identification of CH3CHO was confirmed using gas chromatography-mass spectroscopy. ROFA-induced increases in other lavage fluid carbonyls were not seen. Increased CH3CHO in lavage fluid was observed as late as 8 h later. No increase in CH3CHO was observed in plasma from ROFA-treated rats. An increased formation of CH3CHO was observed in a human airway epithelial cell line incubated with ROFA suggesting a pulmonary source of CH3CHO production. Instillation of solutions of metals (iron, vanadium, nickel) contained in ROFA, or instillation of another ROFA-type particle containing primarily iron, also induced a specific increase in CH3CHO. These data support the hypothesis that metals were involved in the increased CH3CHO formation. Thus metals on PM may mediate lung responses through induction of lipid peroxidation and carbonyl formation.     

Schistosoma mansoni: long-term culture of in vitro derived schistosomula

In vitro derived schistosomula were cultured under various conditions. Variables tested included concentration of organisms, type of culture vessel, frequency of media change, time of erythrocyte addition, antibiotic levels, heated vs unheated serum in the media, and fresh vs stored serum or erythrocytes. No differences were observed between cultures changed every 3 or every 7 days, but worm growth and development were retarded when the culture medium was changed every 2 weeks. Organisms cultured without changing the medium for 3 weeks did not survive. High levels of antibiotics also inhibited growth and resulted in increased mortality. None of the other factors tested resulted in remarkable differences between groups. Some cultures lived for as long as 69 days, and pairing of adult worms was observed as early as 55 days. Most of the cultures, however, were lost before that time from the outgrowth of contaminants which were probably present in the cultures from the outset.     

Effect of Ground Cover on Splash Dispersal of Phytophthora cactorum from Strawberry Fruits

Abstract A rain simulator was used to investigate the influence of various ground covers (soil, straw, sand, and plastic) on splash dispersal of Phytophthora cactorum , the cause of leather rot of strawberry. Potted strawberry plants were held in a concentric circle by a wood frame, 30 cm from an inoculum source of 10 infected fruits with sporulating lesions. The canopy was exposed to 15 and 30 min of generated rain at intensities of 15 and 30 mm/h. Plastic mulch had the highest resulting fruit disease, incidence (e.g., ca. 80% of fruit infected at 30 min duration and 15 mm/h rain), followed by soil and sand (36–47%), then straw (ca. 15%). Except for straw, there was lower incidence at 30 than at 15 mm/h. There was a general increase in disease incidence over time.     

Pulmonary endocrine cells in different varieties of pulmonary vascular disease

The r?le of the endocrine cells which populate the airways of the lung is uncertain, although it has been suggested that one of their functions might be to regulate the pulmonary vasculature. We have studied the number, content and distribution of these cells in 26 pairs of lungs removed during heart-lung transplantation for the treatment of pulmonary hypertension of various causes, none of which were characterized by plexogenic arteriopathy. In comparison with the controls, there were no differences in the number, content or distribution of these cells, although in two cases of recurrent pulmonary thromboembolism they were aggregated into abnormal disorderly clusters.