Data from the National AIDS Behavioral Surveys. III. Multiple sexual partners among blacks in high-risk cities

According to the claims of the manufacturer, aethylcyanoacrylate can be used to bond orthodontic brackets and some orthodontists have already adopted its use for this purpose. Because, however, the use of the material as thus applied has not yet been the object of research, the question of its adhesion to tensile forces immediately after bonding and after 50, 100, and 150 days of placement in a physiologic saline solution (0.9% NaCl) is the subject of this study. 40 bovine upper incisors were extracted from 20 animals for each of the four points in time. The brackets were bonded with Cyano-Veneer and Mono-Lok according to a randomized list. Mono-Lok, an adhesive from the group of common orthodontic adhesives, functioned as the reference material. The bonding strength of the brackets in relation to the tensile forces was measured by means of a "Zwickuniversalprüfmaschine" (Zwick universal testing machine). Immediately after bonding, the cyanoacrylate demonstrated significantly higher bonding strength values than Mono-Lok. At 50, 100, and 150 days in the physiologic saline solution, the bonding strength of both materials showed no significant difference. It can thus be concluded that, when wires are employed immediately after bonding, the danger of bracket loss is significantly reduced through the use of cyanoacrylate.     

In vitro stimulation of human peripheral blood B cells from normal individuals by activated T cells increases the efficiency of hybridoma generation

Peripheral blood B cells from normal individuals have been less than ideal as a resource for "fusible" cells for the generation of human hybridoma antibodies. In vitro stimulation of normal peripheral blood B cells by CD4+ T cells (HUT 78) that had been activated by a solid phase anti-CD3 monoclonal antibody (OKT3) was investigated to see if differentiation of B cells would result in an increased pool of B cells that could be immortalized. A comparison of the rate of successful fusion, an estimation of the frequency of the fusible cells from the input peripheral blood, and the amount of immunoglobulin secreted both in vitro, prior to fusion, and by the resulting clones in two different in vitro immunization protocols, with and without activated T cells indicated that inclusion of the activated T cells provided the necessary help to drive the B cells to a fusible state. Stimulation by activated T cells improves the efficiency of generating B cell hybrid clones from peripheral blood 10-fold compared to in vitro immunization with antigen alone.     

Tunable Thermo‐Responsive Poly(N‐vinylcaprolactam) Cellulose Nanofibers: Synthesis,Characterization, and Fabrication

Temperature‐responsive PVCL homopolymers and functional PVCL polymers containing carboxylic acids are prepared in organic and aqueous solutions. PVCL bulk polymers are characterized using ¹H NMR, photometry, ATR‐FTIR, and thermal analysis. A finite phase transition at 37–40 °C occurs in aqueous solutions of PVCL and PVCL‐COOH. PVCL and PVCL‐COOH polymers are electrospun into fibers ranging from 100 to 2300 nm in diameter. PVCL/cellulose bi‐component films are obtained by electrospinning of CA and PVCL followed by alkaline hydrolysis. These tunable thermo‐responsive PVCL/cellulose nanofibers have potential applications in developing affinity membranes.

     

Phenotype markers in strains of Aeromonas isolated in Cuba from children with an acute diarrheic disease

Twenty-seven cases of Aeromonas isolated from 300 five-years children with acute diarrheal disease (EDA) were studied, with the aim for demonstrating the occurrence of some phenotypical markers associated with enteropathogenicity; among them were lysine decarboxylation, acetil methyl carbinol production, enterotoxigenicity, cytotoxicity and hemolysis. The percentage of analysed strains had two or more of the investigated markers, and 13 (48.1%) lysed the rabbit erythrocytes with titres higher than than 1:16. The presence of markers in Aeromonas hydrophila, Aeromonas sobria, and Aeromonas caviae was demonstrated.     

Diagnostic comorbidity in panic disorder: effect on treatment outcome and course of comorbid diagnoses following treatment

The impact and course of additional diagnoses was examined in 126 patients undergoing cognitive-behavioral treatment for panic disorder. With the Anxiety Disorders Interview Schedule--Revised, a high comorbidity rate (51%) was observed at pretreatment. Pretreatment comorbidity was not predictive of premature termination, nor did it have a substantial impact on short-term treatment outcome. However, patients with comorbidity at posttreatment were more likely to have sought additional treatment over the follow-up interval. Although a significant and dramatic decline in the overall comorbidity rate was found at posttreatment (17%), at 24-month follow-up this rate had increased to a level (30.2%) that was no longer significantly different from pretreatment. This was despite the fact that patients maintained or improved on treatment gains for panic disorder over this interval. The implications of these findings for the treatment, conceptualization, and classification of emotional disorders are discussed.     

A graphical analysis method to estimate blood-to-tissue transfer constants for tracers with labeled metabolites

The Patlak graphical analysis technique is a popular tool for estimating blood-to-tissue transfer constants from multiple-time uptake data. Our objective was to extend this technique to tracers with labeled metabolites, the presence of which can cause errors in the standard Patlak analysis. METHODS: Based on previously described formulations, we generalized the graphical technique for use under specific conditions. To test the extended graphical approach, we applied the method to both simulated and patient data using a preliminary compartmental model for the PET tumor proliferation marker, 2-[11C]-thymidine. RESULTS: When given conditions are met, a linear relationship exists between the normalized tissue activity (tissue activity/blood activity) and a new set of graphical analysis basis functions, including a new definition of normalized time, which takes the presence of labeled metabolites into account. Graphical estimations of the tumor thymidine incorporation rate for simulated data were accurate and showed close agreement to the results of detailed compartmental analysis. In patient studies, the graphical and compartmental estimates showed good agreement but a somewhat poorer correlation than in the simulations. CONCLUSION: The extended graphical analysis approach provides an efficient method for estimating blood-tissue transfer constants for tracers with labeled metabolites.