Immunization of Aotus trivirgatus against Plasmodium falciparum with irradiated blood forms

Five owl monkeys, Aotus trivirgatus, were immunized against falciparum malaria by the intravenous injection of gamma-irradiated parasitized blood from donor monkeys with high parasitaemias. Each animal received approximately 1 x 10(8) parasitized erythrocytes per immunizing dose. Three monkeys received 4 doses and 2 monkeys received a single dose. After challenge, 3 control monkeys that received saline and the 2 monkeys that received a single dose of parasitized blood died with fulminant parasitaemias. The 3 monkeys that received 4 immunizing doses had either no parasitaemia at all (one monkey) or low-grade (<2.5%) parasitaemias (two monkeys); one of the latter monkeys died after the malaria had run a prolonged course. No striking haematological abnormalities were noted in animals as a result of the immunization procedure. These results confirm that immunity to Plasmodium falciparum can be induced in owl monkeys by inoculation with parasitized erythrocytes that have not undergone culture and without the use of adjuvant.

Correlation of tartrazine hypersensitivity with specific serum IgD levels

The clinical diagnosis of hypersensitivity to the food dye tartrazine in 16 subjects correlated with levels of tartrazine-specific IgD antibodies determined by a solid phase radioimmunoassay inhibition test. This is the first study associating hypersensitivity to a low molecular weight chemical with an antibody response of the IgD class. There was little or no correlation between clinical sensitivity and IgE antibodies.

Efficiency of serologic tests in the diagnosis of systemic candidiasis

Candida antibody tests for systemic candidiasis were conducted on 53 sera from patients with the disease and 170 sera from control patients by agar gel diffusion, counterimmunoelectrophoresis (CIE), latex agglutination, and whole-cell agglutination. The agar gel diffusion test and CIE had sensitivity, specificity, and efficiency of approximately 90%. The whole-cell agglutination test scored significantly lower, whereas the latex test scored in between. The agar gel diffusion test had the highest reproducibility and the whole-cell agglutination test the lowest in tests of identical sera by six independent laboratories. The agar gel diffusion and CIE tests make significant contributions to the diagnosis of systemic candidiasis.

Laboratory evaluation of serological tests for systemic candidiasis: a cooperative study

Three serological tests for candidiasis, agar gel diffusion (AGD-1), whole cell agglutination (AGGL-1), and latex agglutination (LAT), were evaluated by six laboratories with 100 coded sera. In addition, each of six laboratories performed a test of its choice, either the AGD-2, the AGD-3, the AGGL-2, or one of three counterimmunoelectrophoresis (CEP) methods (CEP-1, CEP-2, and CEP-3). Results are presented by laboratory for a group of 53 "candida-involved" cases (33 proven, 14 presumptive, and 6 probable) and 47 negative controls (41 normal and 6 other disease states). The AGD-1 test produced an overall average of 85.1% positive results in the candida-involved group and 5.0% positives in the control group. The LAT produced an overall average of 89.0% positives in the candida-involved group and 17.4% positives in the controls. The AGGL-1 test produced an overall average of 63.8% positives in the candida-involved group, with 12.3% positives in the controls. In the individual tests, the best performance was shown by the CEP-3 test (92.5% positives in the candida-involved group and 2.1% positives in controls) and the CEP-1 test (88.7% positive in the candida-involved group and no positives in the controls). The tests with the highest sensitivity were the AGGL-2 and CEP-2 (94.3 and 96.2%, respectively). These tests were also the least specific (80.9 and 76.6%, respectively). In the three common tests, the AGD-1 was the most reproducible, whereas the AGGL-1 produced considerable laboratory-to-laboratory variation. Since cell-free extracts of mechanically disrupted C. albicans were used for the LAT and all the AGD and CEP tests, the difference in performance was considered to be mainly due to antigenic composition and the conditions of the test. The results of this study confirm the value of serological tests for the diagnosis of systemic candidiasis, but point out the need for standardized reagents.

Subunit structure and hybrid formation of bovine pyruvate kinases

After denaturing either type M or L pyruvate kinase by guanidine hydrochloride, urea, or low pH, enzymatic activity and quaternary structure can be recovered by diluting the enzyme into buffer containing beta-mercaptoethanol. After denaturation of type M pyruvate kinase by guanidine hydrochloride, the yield and polarization of the intrinsic protein fluorescence, as well as most of the circular dichroism characteristic of the native enzyme, were regained very rapidly, while enzymatic activity was recovered much more slowly. Under the conditions used, about 50% of the original M and 30-50% of the original type L activity were typically recovered. Average half-times for recovery of enzymatic activity were 37 min for type M and 104 min for type L but depended somewhat on the renaturation buffer and on protein concentrations in the renaturation medium. If types M and L pyruvate kinases are renatured together, an approximately random recombination of the two subunits types results in a five-membered hybrid set. We have used this hybridizability to determine the kinetics of reformation of the native tetramer by denaturing each isozyme and beginning its renaturation separately at various times mixing the two isozymes and continuing their renaturation together. These studies indicate that reformation of stable tetramers occurs relatively slowly, qualitatively paralleling the regain of enzymatic activity, and that tetramer formation may be necessary for enzymatic activity. Using a similar technique to test for spontaneous dissociation of the native isozymes in buffer, we find that type L, but not type M, reversibly dissociates into dimers and monomers in buffer solutions. This dissociation is decreased by the presence of the substrate, phosphoenolpyruvate, by Mg2+ ions, or by the allosteric effector, fructose bisphosphate.

Characterization of an adenovirus early protein required for viral DNA replication: a single strand specific DNA binding proteins

1. The human adenoviruses types 2, 5 and 12 code for the production of a single strand specific DNA binding protein. The molecular weights of these proteins were 72,000 for types 2 and 5 and 60,000 for type 12. In all three cases proteolytic breakdown fragments of these binding proteins (48,000 MW) were also observed. 2. Analysis of the methionine containing tryptic peptides of these proteins indicate that the types 2 and 5 proteins are similar and clearly distinguishable from the type 12 protein. The peptide maps of these three viral proteins are clearly different from a similar protein found in mock infected cells. 3. Temperature sensitive mutants of type 5 (H5ts125) and type 12(H12tsA275) adenoviruses fail to produce these proteins at the nonpermissive temperature. H5ts125 infected cells grown at the permissive temperature produce a 72,000 MW protein that is thermolabile, for continued binding to DNA, when compared to type 5 wild type adenovirus 72,000 MW protein. An analysis of the phenotype of this adenovirus mutant indicates that it codes for a viral function at early times after infection that is required for viral DNA replication. 4. The in vitro translation of adenovirus specific m-RNA results in the synthesis of a small amount of a 72,000 MW protein that binds to single stranded DNA just like the authentic adenovirus DNA binding proteins produced in infected cells. 5. Adenovirus anti-Tumor antigen (T) anti-serum from hamsters carrying independently derived adenovirus tumors, have been tested for the presence of antibody to purified DNA binding proteins. One antiserum is positive for these antibodies while the other is negative. These results indicate that some, but not all, adenovirus tumors contain large enough levels of the DNA binding proteins to elicit an antibody response. 6. The type 5 adenovirus temperature sensitive mutant, H5ts125, that codes for a thermolabile DNA binding protein, was complemented or suppressed at the nonpermissive temperature, for the replication of adenovirus DNA, by SV40. SV40tsA temperature sensitive mutants, defective in SV40 DNA replication, do not suppress or complement H5ts125 at the nonpermissive temperature.

The relationship between group C adenovirus tumor antigen and the adenovirus single-strand DNA-binding protein

The group C adenoviruses code for a single-strand specific DNA-binding protein of molecular weight 72,000 daltons which is synthesized at early times after productive viral infection. Experiments were designed to determine whether this single-strand specific DNA-binding protein was expressed in adenovirus tumors and transformed cells. Two independently derived preparations of anti-sera from hamsters bearing group C adenovirus tumors were tested for antibody against the single-stranded DNA-binding proteins. One antiserum contained antibodies that reacted with these DNA-binding proteins, while the second antiserum did not contain detectable levels of antibody. Five adenovirus type 2 transformed rat cell lines were tested for the presence of the single-stranded specific DNA-binding proteins. Two of the five transformed cells expressed detectable levels of this protein. These results indicate that the group C adenovirus single-strand specific DNA-binding proteins are expressed in some, but not all, adenovirus tumors and transformed cell lines. Those transformed cell lines (type 2) containing a portion of the adenovirus genome designated by the Eco R-I-B restriction enzyme fragment express the single-strand specific DNA-binding proteins. Those cell lines missing this Eco R-I-B fragment do not contain this viral protein. Other experiments have located the structural gene of the signle-strand specific DNA-binding protein in the Eco-R-I-B DNA fragment, indicating that when this gene is present in a transformed cell, it is expressed.

The new graduate in the operating room

New graduate nurses today come to their first positions in nursing with varying knowledge bases and minimal clinical nursing skills. Gone are the days when new graduates begin functioning fully in a budgeted position on day one of employment. Mastery of psychomotor, cognitive, and affective skills necessary for nursing practice must be acquired through experience in the work situation. The more complex the clinical setting, the more stressful is the period of learning. The O.R. can be a highly stressful place. The need for anticipation, planning and organization to provide efficient care with meticulous attention to detail is coupled with the need to perform smoothly numerous technical skills. Safe, humanistic care cannot be implemented unless the nurse is also able to assess each patient's individual biopsychosocial status, and identify his unique nursing care needs. In order to learn to cope with this level of complexity, the neophyte nurse must be provided with a planned, supportive experiential learning situation that also provides the time necessary to achieve a beginning level of mastery. The program in Basic O.R. Nursing described here was one attempt to provide such an experience for new graduates.

Effect of alloxan on permeability and hexose transport in rat pancreatic islets

The in vitro effect of alloxan exposure on the permeability of collagenase isolated rat pancreatic islets to sucrose, D-mannitol, and L-glucose has been investigated. Determination of changes in cell volume with a non-wash double label isotope procedure indicates that alloxan treatment exerts no measurable effect on permeability to sucrose, D-mannitol, or L-glucose as compared to nonalloxan-treated islets. In addition, neither prior exposure nor the concomitant presence of alloxan alters the rate of D-glucose or 3-0-methyl-D-glucose transport into rat pancreatic islets. It is concluded that the in vitro effect of alloxan on abolishing glucose-induced insulin release in isolated rat pancreatic islets does not appear to be the result of permeability changes to small organic molecules or alteration in the transport of D-glucose into the beta-cell.

A comparative study of the relative ease of thermolytic depurination vs. depyrimidination in 2'-deoxynucleosides

Following fusion, 2′-deoxynucleosides undergo thermolytic cleavage to produce furfuryl alcohol and water along with the corresponding base. Contrary to previous suggestions, pyrimidine as well as purine deoxynucleosides are subject to base cleavage, the relative ease of thermolysis being 2′-deoxyguanosine > 2′-deoxyadenosine > 2′-deoxycytidine > 2′-deoxyuridine > thymidine. When dissolved in dimethyl sulfoxide, these nucleosides are susceptible to a similar cleavage at a lower temperature, with guanine being liberated from deoxyguanosine much more readily than adenine from deoxyadenosine, a feature which was in agreement with observations of Greer and Zamenhof (J. Mol. Biol. 4, 123 (1962)) regarding thermal depurination of DNA.