A comparative immunogenicity-reactogenicity dose-response study of influenza vaccine

This study examined the immunogenic and reactogenic responses of influenza vaccine in 29 healthy nonallergic adults at three vaccine dosages: 0.5 mL, 0.1 mL, and 0.05 mL. After immunization a 7-day assessment of adverse reactions was made and serial serum hemagglutination-inhibition (HAI) antibody responses were measured during a 28-day period. The incidence of adverse reactions was significantly decreased in the group receiving 0.1 mL and 0.05 mL compared with the group receiving 0.5 mL of vaccine. After immunization with 0.1 mL or 0.05 mL vaccine increases in serum HAI antibody to A/Leningrad, A/Taiwan, and B/Ann Arbor influenza antigens were seen comparable to those observed after 0.5 mL. However the magnitude of these rises were lower and were directly correlated with the dose of vaccine. Since immunization of egg-sensitive allergic patients with influenza vaccine poses a risk of localized and systemic reactions, a common clinical practice is to prevent such reactions by vaccine dilution. Although the results of the present study suggest that vaccine dilution results in a decrease in adverse reactions, there is also the risk of decrease protective immunity with this procedure and therefore the practice should not be condoned.     

Neuronal population of area 4 during the life span of the rhesus monkey

One right or left area 4 of each of 19 rhesus monkeys, ranging in age from 1 day to 35 years, was processed (frozen sectioned at 30 or 40 microns) for light microscopic analysis to assess age-related changes in the neuronal population. All neurons were examined regardless of their size. In addition, Betz cells were analyzed separately; to be regarded as Betz cells, pyramidal somata had to display a minimum height of 38 microns. A significant loss of approximately one-third was observed in the total number of neurons in maturing monkeys (less than 5.5 years). In contrast, in maturing rhesus monkeys significant increases with age were observed in the mean number of Betz cells, and in the means of Betz cell area, height, width, perimeter, and estimated volume. In adult monkeys (greater than 4.5 years), no age-associated loss of neurons was observed. Also, no loss of Betz cells occurred, although the perimeter, area, and estimated volume of Betz cells decreased slightly, but significantly, with increasing age in adult monkeys. Lipofuscin granules were discernable in Betz cells beginning at the age of 5 years and their number increased with increasing age. In the older rhesus monkeys, the lipofuscin granules were so large and numerous that in some Betz cell somata they displaced the nucleus from its usual location in the center of the cell. No age-related change in thickness of area 4 was found.     

Shock avoidance conditioning and 3H-leucine uptake in a simple vertebrate system.

Myelencephalic grass frogs were trained to avoid shock to a forelimb, in the paradigm of Horridge. Forty-five min after training, these animals reached the criterion for conditioning faster and with fewer mistakes. Yoked control animals exhibited a slight learning deficit 45 min after receiving unavoidable shocks. Thirty min after training there was no difference in total protein content in the neuraxes of trained and yoked animals, but trained animals incorporated relatively more ³H-leucine into presumptive protein. The incorporated radio-activity was largely confined to the half of the neuraxis ipsilateral to the trained limb, but was not consistently confined to any 1 level of the neuraxis. The simplicity of this behavior and the relatively simple neuronal circuitry mediating it recommend this as a useful vertebrate model system for the study of macromolecular correlates of learning.     

Immune deficiency following thermal trauma is associated with apoptotic cell death

Thermal injury-associated specific immune deficiency occurs despite indicators of systemic activation of the lymphoid compartment. We investigated the possibility that postburn immune failure and T cell activation are causally related through activation-induced (apoptotic) cell death. The relationship between the cellular immune response and cell mortality was examined in cultures of peripheral blood mononuclear cells (PBMC) from 14 immunosuppressed patients with extensive burns (35–90% total body surface area). Impaired cellular immunity coincided with significantly reduced cell viability as ascertained by propidium iodide staining and dye reduction assays. Following stimulation with the mitogenic lectin, phytohemagglutinin (PHA), the majority of DNA in patient cultures was fragmented, suggesting the occurrence of apoptotic cell death. Even without stimulation a portion of patient cells was apoptotic as indicated by oligonucleosomal bands on agarose gel electrophoresis. Exogenous interleukin-2 or phorbol ester markedly reduced constitutive as well as PHAinduced DNA fragmentation.In situ demonstration of DNA strand breaks in freshly isolated patient PBMC, by a TdT-based labeling technique, confirmed that a larger fraction (up to 60%) of circulating lymphocytes was undergoing apoptosis on the periphery. These novel observations suggest that apoptosis may play a major role in thermal injury-related cellular immunodeficiency.     

Familial testicular cancer: interest in genetic testing among high-risk family members.

PURPOSE: This study is part of an ongoing National Cancer Institute multidisciplinary, etiologically-focused, cross-sectional study of Familial Testicular Cancer (FTC). The current report targets interest in clinical genetic testing for susceptibility to FTC. METHODS: Demographics, knowledge, health beliefs, and psychological and social factors were evaluated as covariates related to interest in genetic testing. RESULTS: The majority (66%) of 229 participants (64 affected men, 66 unaffected men, and 99 women) from 47 multiple-case FTC families expressed interest in having a genetic test within 6 months, should such a test become available. Interest was similar among the three subgroups mentioned above. Worries about insurance discrimination based on genetic test results were associated with a significantly lower interest in testing. Alternatively, participants were more likely to be interested in genetic testing if they were younger and had higher levels of family support, a physician's recommendation supporting testing, cancer distress, and a need for information to inform the health care of their children. CONCLUSIONS: This study reveals social and relationship factors that FTC survivors and their relatives considered important when contemplating the use of new genetic technologies. This is the first study describing hypothetical interest in genetic testing for familial testicular cancer.     

Hepatic iron overload in birds: Analytical and morphological studies

Hepatic iron content was determined in post mortem specimens from a wide range of avian species collected over a 12-month period. The majority (> 90%) of these specimens (n = 40) showed high iron content (up to 12 mg Fe/g tissue). The highest concentrations were associated with fibrosis and regenerative nodules. Dietary analysis indicated that the iron intake was not excessive, suggesting that iron-loading was due to enhanced intestinal absorption.     

Flow cytometric leucocyte counts

A flow cytometric method was evaluated for performing total leucocyte counts on bovine blood. Fifty blood samples from 19 healthy Holstein cows were analysed on a flow cytometer. The method involved diluting blood with either hypotonic or isotonic saline solution, lysing the red blood cells, and performing a 2-parameter analysis on the basis of cell size and cellular granularity. Leucocyte numbers were determined by creating a window on dot plots of cell size (determined by forward light scatter) vs cellular granularity (determined by the logarithm of side light scatter). Total leucocyte counts determined by flow, cytometer with either diluent were lower (p<0.01) than counts determined by use of an electronic particle counter. The correlations between electronic particle counts and flow cytometric counts using isotonic or hypotonic diluents were 0.857 and 0.458, respectively. The determination of total leucocyte counts using flow cytometry of a blood sample diluted in isotonic saline and treated to lyse red blood cells shows potential as a way for counting leucocytes.