Identification of Babesia bigemina infected erythrocyte surface antigens containing epitopes conserved among strains

The presence of previously uncharacterized antigens (new antigens) on the surface of intact erythrocytes infected with three strains of Babesia bigemina from Kenya and one each from Puerto Rico, Mexico, St. Croix, and Texcoco-Mexico was demonstrated by indirect immunofluorescent antibody (IFA) reactions. These antigens were not strain specific because antibodies in bovine immune serum to either the Mexico or Kenya isolates reacted with all seven strains tested. Homologous and heterologous immune serum antibodies bound a maximum of 83% and 55%, respectively, of intact erythrocytes infected with the Kenya-Ngong strain but not uninfected erythrocytes. Both sera caused agglutination of only infected erythrocytes. Antibodies eluted from the surface of glutaraldehyde (0.25%) fixed infected erythrocytes had IFA reaction patterns among strains similar to those of immune sera before elation. Eluted antibodies were used to determine if these antigens were protein and encoded by B. bigemina. Eluted antibodies bound seven parasite-encoded proteins of 240, 220, 66, 62, 58, 52 and 38 kDa in an erythrocyte surfacespecific immunoprecipitation reaction of ³⁵-methionine labelled proteins. It was concluded that the surface of B. bigemina infected erythrocytes had parasite-encoded proteins and that these proteins had surface exposed epitopes that were conserved among the seven strains examined which were from two continents.     

A 90-Day Inhalation Toxicity Study of Raw Shale Oil in Fischer 344 Rats

A 90-Day Inhalation Toxicity Study of Raw Shale Oil in Fischer344 Rats. GORDON T., STROTHER, D. E., CRAMER, D. V., AND GOODE,J. W. (1987). Fundam. Appl. Pharmacol. 9, 287–296. Thepotential health effects of a raw shale oil were evaluated ina 90-day inhalation study in Fischer 344 rats. Groups of 15male and 15 female rats were exposed 6 hr/day, 5 days/week for13 weeks to aerosol concentrations of 0, 56, 120, or 492 mg/m³.In the high-dose group, 10 males and 7 females died prior tothe termination of the study, most within the first 5 weeksof the experiment. A dose-dependent suppression in weight gainwas seen in all of the shale oil-exposed groups. The failureto gain weight was associated with a variety of clinicopathologicabnormalities, including a dose-related decrease in red andwhite blood cells, with lowered plasma protein levels and increasedserum alkaline phosphatase, and with total bilirubin levelsin males. The exposure of the test animals to aerosolized rawshale oil was also associated with inflammatory and hyperplasticlesions in the lungs and upper respiratory tract, atrophy ofthe thyrnus and thymic-dependent portions of the peripherallymphoid system, and bone marrow. These changes demonstratethat inhalation of raw shale oil aerosol can produce major organtoxicity similar to that found after exposure to other unrefinedoil products.     

Technical Grade but Not Recrystallized {alpha}-Naphthylthiourea Potentiates Superoxide Release by Rat Neutrophils Stimulated in Vitro by Phorbol Myristate Acetate

Technical Grade but Not Recrystallized -Naphthylthiourea PotentiatesSuperoxide Release by Rat Neutrophils Stimulated in VitrobyPhorbol Myristate Acetate. ROTH, R.A., AND BALL, T.M. (1986).Fundam. Appl. Toxicol. 7, 324–328. -Naphthylthiourea (ANTU)causes pulmonary edema and pleural effusion in rats. It hasbeen suggested that ANTU pneumotoxicity may be mediated by bloodneutrophils (PMNs) via the release of reactive oxygen species.Accordingly, we tested the effect of technical grade ANTU (tANTU)on the ability of rat peritoneal PMNs to release superoxide(O₂). tANTU did not itself stimulate O₂ production by PMNs,but it increased the O₂ released in response to PMN stimulationby phorbol myristate acetate (PMA). This effect was dependentupon the amount of tANTU added. In PMNs activated in vitro bya submaximal PMA stimulus, addition of 20 µg/ml tANTUdoubled superoxide release. When tANTU was recrystallized fromethanol, the purified ANTU was not effective in potentiatingthe effect of PMA on PMNs. This suggests that an impurity intechnical grade ANTU is capable of increasing O₂ release bystimulated PMNs. tANTU and recrystallized ANTU caused similarpneumotoxicity in rats in vivo, suggesting that the unidentifiedimpurity does not markedly influence the biologic effects ofANTU.     

Functional Electrical Stimulation: An Overview

The development of future neural prostheses involves much more than connecting commercially available stimulators to disabled individuals. Safe and effective operation of prostheses requires fundamental studies of the electrode-tissue interface. The electrochemistry of the interface must be controlled to prevent toxic byproducts. Histopathological studies of stimulated tissue are necessary to establish safe limits of stimulation and to determine mechanisms of neural damage when it does occur. Electrophysiological studies elucidate which neural pathways are excited and help in the design of more selective electrode arrays. Biomaterials are required that protect the implant from the hostile environment of the body. Presently available materials are being improved and totally new materials are being developed. One of the goals of neural prostheses developers is a nonhermetic packaging material that can be applied to miniature implants without appreciably increasing their size. The techniques used to make integrated circuits on silicone substrates are ideally suited to making ultraminiature electrodes with self-contained electronic signal processing. Both integrated circuit stimulating and recording electrodes are being designed and fabricated.     

The SdaBlood Group Antigen in Tissues and Body Fluids

Abstract. In man the Sd^aantigen is present in most secretions with the greatest concentration in urine. There is little difference in the amount of Sd^asubstance in the urine of newborn infants, pregnant women and normal adults but there is a much greater amount in the saliva of newborn infants than in adults. Approximately half the people whose red cells group as Sd(a-) secrete Sd^asubstance in the urine. Anti-Sd^aantibody is present in 50% of Sd(a-) non-secretors of Sd^asubstance, though most of these antibodies only react with the strongest Sd(a +) cells. The greatest Sd^aactivity has been found in human meconium, guinea pig urine and guinea pig kidney. Activity can be detected in the urine of many animal species. The kidneys of 5 bird species did not contain Sd^a.     

Nursing leadership style and psychosocial work environment

malloy t. & penprase b. (2010) Journal of Nursing Management  18 , 715–725
Nursing leadership style and psychosocial work environment Aim This study examines the relationship between leadership style and the psychosocial work environment of registered nurses. Background Research consistently supports the positive relationship between transformational leadership style and job satisfaction. There is less evidence, which identifies the relationship between leadership style and psychosocial work environment. Method The Multifactor Leadership Questionnaire 5× was used to identify the leadership style. The Copenhagen Psychosocial Questionnaire was used to measure psychosocial work environment dimensions. Statistical analysis included Pearson’s r correlation between leadership style and psychosocial work environment and anova to analyse group means. Results There is a significant correlation between leadership style and 22 out of the 37 dimensions of the psychosocial work environment. This correlation was significant ranging from r = 0.88, P < 0.01 to r = 0.18, P < 0.05. Nurses divided into groups based on transformational leadership scores of the immediate supervisor report significant differences in their psychosocial work environment. Conclusion This study supports the significant correlation between leadership style and psychosocial work environment for registered nurses. Implications for nursing management The results of this study suggest that there would be an improvement in the nursing psychosocial work environment by implementation of transformational and contingent reward leadership behaviours.     

Some properties of a nonautonomous deterministic growth model describing the adjustment of the bacterial population to a new environment

Present address: Unilever Research, Colworth Laboratory, Colworth House, Sharnbrook, Bedford MK44 1LQ, UK. Some mathematical properties of a simple nonautonomous deterministicgrowth model are presented. The model describes the lag phaseof bacterial growth as an adjustment of the population to anew environment after inoculation. A useful family of ‘adjustmentfunctions’ is considered and some of its mathematicalproperties are given.     

The consistency of family and peer influences on the development of substance use in adolescence

Latent growth modeling (LGM) was used to analyse longitudinal data for adolescent substance use from five overlapping age cohorts (11, 12, 13, 14 and 15 years at first assessment) measured at four annual time points. An associative cohort-sequential model was tested for alcohol, cigarette and marijuana use with a sample of 345 adolescents (11–18 years old) from an urban area in the Pacific Northwestern region of the United Stales. Hypotheses concerning the shape of the growth curve, the extent of individual differences in the common trajectory over time, and the influence of family cohesion, peer encouragement and gender on initial substance use and shape of the growth curve were tested. Results indicated similarities between alcohol, cigarette and marijuana initial use and development, with peer encouragement and family cohesion predictive of initial levels of use, and changes in peer encouragement influencing the developmental trajectories of the three substances. Females were higher than males in initial status and developed less rapidly in their use of the substances than did males. Findings are discussed in terms of the similarities and differences in the developmental trajectories of the three substances and the importance of family and peer influences on these trends.