Quantitative assays of pharmacologic aerosols used in studying asthma

To more nearly accurately quantitate the dose of pharmacologic agents delivered to human and animal airways via aerosols, we have developed a monodisperse aerosol containing either methacholine or histamine that permits a light scattering device (tyndallometry) to measure accurately the quantity of inspired and expired particles. These aerosols (described in previous studies) are simultaneously tagged with a radioactive label (technetium 99m) to permit the use of external gamma camera imaging. Present work focuses on the development of assay techniques to measure the quantity of methacholine delivered in these aerosols. The lack of specific radioimmune or radioenzyme assays coupled with the cross-reaction of organic contaminants with conventional chemical reagents for measuring methacholine required the development of separative techniques to isolate the methacholine from the organic aerosol contaminants. With aqueous extraction and column separation we have been able to completely isolate the methacholine from these contaminants. This allows the application of standard spectrophotometric assays for methacholine to quantitate the methacholine in the resulting solution. These separative techniques will permit the use of these aerosols in quantitative studies of airway reactivity.     

Evaluating plasma holds in the presence of multiple infections

To protect plasma supplies, donors are screened for infectiousdiseases. As an added measure of protection, donations are identifiedand stored for a period of time to allow future discard in theevent that an identified donor subsequently tests positive forsome screened disease. Previous models for evaluating such plasmaholds have only addressed the case of a single infectious disease.This paper extends the analysis to the case of multiple infections.Given knowledge of the marginal incidence rates for those infectionschecked, upper and lower bounds for important quantities suchas the probability of interdicting an infectious but undetecteddonation, the expected number of infections interdicted perdonation, and the net economic benefits of the holding policyare developed. Several examples are developed, illustratinghow the models can be used to evaluate the consequences of aplasma hold.     

Linkage analysis of anorexia and bulimia nervosa cohorts using selected behavioral phenotypes as quantitative traits or covariates.

To increase the likelihood of finding genetic variation conferring liability to eating disorders, we measured over 100 attributes thought to be related to liability to eating disorders on affected individuals from multiplex families and two cohorts: one recruited through a proband with anorexia nervosa (AN; AN cohort); the other recruited through a proband with bulimia nervosa (BN; BN cohort). By a multilayer decision process based on expert evaluation and statistical analysis, six traits were selected for linkage analysis (1): obsessionality (OBS), age at menarche (MENAR), and anxiety (ANX) for quantitative trait locus (QTL) linkage analysis; and lifetime minimum body mass index (BMI), concern over mistakes (CM), and food-related obsessions (OBF) for covariate-based linkage analysis. The BN cohort produced the largest linkage signals: for QTL linkage analysis, four suggestive signals: (for MENAR, at 10p13; for ANX, at 1q31.1, 4q35.2, and 8q13.1); for covariate-based linkage analyses, both significant and suggestive linkages (for BMI, one significant [4q21.1] and three suggestive [3p23, 10p13, 5p15.3]; for CM, two significant [16p13.3, 14q21.1] and three suggestive [4p15.33, 8q11.23, 10p11.21]; and for OBF, one significant [14q21.1] and five suggestive [4p16.1, 10p13.1, 8q11.23, 16p13.3, 18p11.31]). Results from the AN cohort were far less compelling: for QTL linkage analysis, two suggestive signals (for OBS at 6q21 and for ANX at 9p21.3); for covariate-based linkage analysis, five suggestive signals (for BMI at 4q13.1, for CM at 11p11.2 and 17q25.1, and for OBF at 17q25.1 and 15q26.2). Overlap between the two cohorts was minimal for substantial linkage signals.     

Menstrual Cycle Phase is a Potential Confound in Psychophysiology Research

Effects of menstrual cycle phase on physiological levels and reactivity were studied in a withinsubject design with 20 women aged 18–30 years. Basal body temperature was monitored daily; follicular and luteal recording sessions occurred before and after the ovulatory temperature rise, respectively. The design consisted of task and rest periods, presented in counterbalanced order across phases. Half the subjects began during their follicular phase and half began during their luteal phase. Follicular and luteal phases were compared for differences between baseline resting levels, as well as for reactivity. The results showed menstrual phase differences in heart rate, pulse transit time, and EEG alpha, particularly during tasks, but no difference in reactivity. Habituation effects in the group that began during the follicular phase often masked luteal activation. In spite of the fact that not all statistical results achieved significance, the consistency of most trends supports the conclusion that physiological recording sessions with women might best be restricted to the follicular phase.     

Electron microscopic studies of the DNA of defective and standard pseudorabies virions.

DNA from standard and defective virus particles was analyzed by electron microscopy. Upon partial denaturation the DNA molecules from standard pseudorabies virus showed distinct denaturation patterns. The molecules are asymmetrical with respect to adenine-thymidine (A-T) content, having several A-T-rich regions on the “left” side and only one on the “right” side of the molecule. The fact that a distinct denaturation map was obtained indicates that the molecules are not circularly permuted. On the extreme left of the molecule a segment of approximately 0.5 μm invariably contained denatured regions, whereas this was not evident on the right side of the molecule. Thus, if the molecule is terminally redundant, the redundant region covers a relatively small part of the viral genome. The contour length of the DNA molecules present in defective, interfering particles was found to be similar to that of standard DNA. Under partial denaturation conditions a distinct segment of DNA (1.1 μm in length) was found to be tandemly repeated in defective DNA. The number of repeats in different molecules varied. In some of the DNA molecules as many as 17 consecutive repeats were found, whereas in others no repeats were seen. Repeated segments were not detected in standard DNA.     

Solid phase interleukin 2

Interleukin 2 was bound to Sepharose beads in order to assess its potential bioactivity in vitro. Although the cytokine was attached to the solid phase via a standard chemical reaction for covalent coupling, it was spontaneously released into culture medium in an active form during short-term incubation. Release was absolutely dependent on the availability of soluble protein in the incubation medium, and it was greater at 37 than at 4 degrees C. Approximately 80% of the cytokine attached to the Sepharose beads was recovered in the medium after appropriate incubation for several days. The release of interleukin 2 from the solid phase resulted from the dissolution of aggregated cytokine. Noncovalent self-aggregation of interleukin 2 onto solid surfaces represents an unusual biochemical property that has implications for the molecular interactions of the cytokine with the solid phase, for the use of bound interleukin 2 in preparative or analytical modes, and for the development of immunotherapy for patients with solid tumors.     

Freeze Dried Platelets for HLA Alloantibodies Absorption

Antibodies to HLA–A and B are specifically absorbed onto platelets. A method of absorption of these antibodies using freeze dried platelets is described. This method allows long-term storage and standardized absorption procedures. Anti-DR antibodies and cold lymphocytotoxins are recovered in the supernatant.     

Three-dimensional aqueous-derived biomaterial scaffolds from silk fibroin

A new all-aqueous process is described to form three-dimensional porous silk fibroin matrices with control of structural and morphological features. The result of this process are scaffolds with controllable porosity and pore sizes that fully degrade in the presence of proteases, unlike prior methods to generate silk-based biomaterials that required the use of organic solvent treatments to impart control of structure and stability in aqueous environments, with low rates of proteolytic hydrolysis. A mechanism is proposed for this novel process that imparts physical stability via hydrophobic interactions. Adjusting the concentration of silk fibroin in water, and the particle size of granular NaCl used in the process, leads to the control of morphological and functional properties of the scaffolds. The aqueous-derived scaffolds had highly homogeneous and interconnected pores with pore sizes ranging from 470 to 940 microm, depending on the mode of preparation. The scaffolds had porosities >90% and compressive strength and modulus up to 320 +/- 10 and 3330 +/- 500 KPa, respectively, when formed from 10% aqueous solutions of fibroin. The scaffolds fully degraded upon exposure to protease during 21 days, unlike the scaffolds prepared from organic solvent processing. These new silk-based three-dimensional matrices provide useful properties as biomaterial matrices due to the all-aqueous mode of preparation, control of pore size, connectivity of pores, degradability and useful mechanical features. Importantly, this process offers an entirely new window of materials properties when compared with traditional silk fibroin-based materials.     

First reported case of streptococcus pyogenes infection with toxic shock-like syndrome in Italy

A 43-year-old male who sustained a superficial hand injury developed streptococcal toxic shock-like syndrome and died within 48 hours. The clinical course of the illness in this previously well patient was rapid and fulminant. The organism responsible was a group A beta-hemolytic streptococcus which was identified as opacity factor negative, M serotype 1, T type 1. The organism produced streptococcal pyrogenic exotoxins B and C, but no detectable exotoxin A although it carriedspeA, the gene for exotoxin A. This is the first case reported in Italy, and further emphasizes the virulence of these organisms and the rapidity with which the illness can progress.     

Separation distress and attachment in surrogate-reared squirrel monkeys.

Surrogate-reared infant squirrel monkeys were exposed to various conditions of separation from their surrogate. Infants showed significant increases in plasma levels of cortisol when they were placed in an unfamiliar environment during the separation period. Changes in behavior, but not cortisol, were observed under conditions in which the surrogate was removed and the infant left in the home cage. These results differ from those previously obtained with mother-reared infants. It is concluded that surrogate-reared infant squirrel monkeys do not show the same separation response or attachment to their rearing figure as do mother-reared infants.