The effect of IL-4 on human nasal mucosal responses

Interleukin (IL)-4 causes the dose limiting sensation of nasal congestion when administered systematically at doses of 3 micrograms/kg or higher thrice daily to humans. This side effect was observed in a group of patients treated as part of an immunotherapy protocol for cancer management. To determine the source of this congestion, nasal secretions were collected prospectively in a group of patients at baseline and after provocation with normal saline, methacholine (which stimulates glandular secretion), and histamine (which causes increased vascular permeability). Nasal lavages obtained at baseline and after provocation were analyzed for the presence of these glandular and vascular proteins and inflammatory mediators. Washings and provocations were performed before IL-4 administration, after 24 hours of IL-4 treatment, and after 3 days of treatment, at a time when nasal congestion was maximal. Compared with histamine challenge before IL-4 treatment, the secretion of the plasma proteins albumin and IgG were significantly decreased after 3 days of IL-4 treatment. IL-4 treatment had no apparent effect on methacholine-induced responses. Thus systemically administered IL-4 causes the subjective sensation of nasal congestion, increased histamine in nasal lavages, and the development of vascular unresponsiveness to histamine, without affecting parasympathetic responses to histamine. The relationships among increases in nasal lavage histamine, vascular unresponsiveness to histamine, and the sensation of nasal congestion are unclear.     

Clinical comparison of isoflurance and halothane anesthetics

Isoflurane and halothane were compared in two similar groups of 100 patients each. Isoflurane compared favorably with halothane in producing adequate anesthesia in all our patients. Induction period was a little stormy when there was direct induction with isoflurane. Maintenance was excellent and recovery was good. Mean concentration necessary to induce anesthesia was 3.07% with isoflurane and 2.56% with halothane. Mean maintenance with isoflurane was 1.39%, compared to 1.40% with halothane. Less curare was required for relaxation when used with isoflurane than with halothane. This difference was not seen with pancuronium (Pavulon). Patient recovery was faster with isoflurane than with halothane. Incidence of delirium and shivering in the recovery period was similar for both agents. Incidence of nausea and vomiting was greater with isoflurane. Other clinical and biochemical postoperative comparisons did not show any significant differences between the two agents.     

Peptido polysaccharide antigens from Trichophyton mentagrophytes var. granulosum

Two highly purified peptido polysaccharide antigens have been isolated from surface-grown cultures of Trichophyton mentagrophytes var. granulosum. Trichloroacetic acid extraction and ethanol precipitation yielded a mixture containing high-molecular-weight components which were first separated on Sephadex G-200. Subsequent fractionation by ion-exchange chromatography on DE-52-cellulose (borate form) yielded the two peptido polysaccharides. Both of the peptido polysaccharides reacted with rabbit antiserum to T. mentagrophytes var. granulosum. The two peptido polysaccharides contain 73.2% hexoses (mannose-galactose-glucose, 7.5:0.7:1), 8.6% amino acids and 1.8% amino sugars and 77.4% hexoses (mannose-galactose-glucose, 9:0.3:1), 6.2% amino acids, and 0.4% amino sugars, respectively. Each contains 16 different amino acids, threonine, proline, and serine predominating.     

Complement activation in septic shock due to gram-negative and gram-positive bacteria

Whole serum complement (CH50) and C3, C4, and C3PA plasma values were studied in 48 patients: 9 with nonseptic shock; 20 with sepsis; 14 with septic shock caused by gram-negative bacteria; 5 with septic shock caused by gram-positive bacteria. All were compared with a control group of 25 healthy individuals. Determinations were made upon admission and again 48 and 96 h later. No significant differences in complement values were found between the patients with nonseptic shock and the control group. In the patients with sepsis, decreased CH50 (p less than 0.001) and increased C3PA (p less than 0.02) values were observed, while C3 and C4 remained unaltered. In the patients with septic shock, markedly decreased levels of CH50, C3, and C4 were seen (p less than 0.001, and p less than 0.001, and p less than 0.001, respectively) without changes in C3PA levels. There were no differences between septic shock due to gram-negative and gram-positive bacteria, or between patients who died and those who survived. After 96 h, the altered values returned to the normal range. This underlines the transitory activation of the complement system through the classic pathway and suggests its possible role in the pathogenesis of septic shock in man.     

Standards of decision regarding personality factors in questionnaires.

In a previous study, E. Howarth and J. Browne (see record 1971-29076-001) factor analyzed personality questionnaire items and concluded that the primary personality structure found by J. Guilford and R. Cattell should be reevaluated according to independent item-factoring. DeYoung criticizes this study for not meeting adequate standards regarding (a) decision as to the number of factors, (b) choice of communalities, and (c) rotation. DeYoung supports the marker structure found by Cattell. In a separate article, Howarth and Browne justify their methodology and refute DeYoung's position. (16 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Regularized tessellation density estimation with bootstrap aggregation and complexity penalization

Locally adaptive density estimation presents challenges for parametric or non-parametric estimators. Several useful properties of tessellation density estimators (TDEs), such as low bias, scale invariance and sensitivity to local data morphology, make them an attractive alternative to standard kernel techniques. However, simple TDEs are discontinuous and produce highly unstable estimates due to their susceptibility to sampling noise. With the motivation of addressing these concerns, we propose applying TDEs within a bootstrap aggregation algorithm, and incorporating model selection with complexity penalization. We implement complexity reduction of the TDE via sub-sampling, and use information-theoretic criteria for model selection, which leads to an automatic and approximately ideal bias/variance compromise. The procedure yields a stabilized estimator that automatically adapts to the complexity of the generating distribution and the quantity of information at hand, and retains the highly desirable properties of the TDE. Simulation studies presented suggest a high degree of stability and sensitivity can be obtained using this approach.     

Head injury

Starling's concept, "mean systemic pressure", is considered and its implications discussed. It is argued that since cardiovascular capacity and blood volume must obviously always be identical, any addition to or loss from the blood must simply compel an identical change in vascular capacity, without necessarily being associated with any change in venous return. Reasons are given for a need to differentiate between pressure and compression, and for appreciating that though the two are usually equal to one another, the second is not the cause of the first (as it is often thought to be). Indeed, the origin of blood pressure is the net osmotic pressure of plasma. We have demonstrated experimentally that Starling's method of measuring "mean systemic pressure" did not correspond to mean vascular compression during life. Moreover, when we remeasured mean systemic pressure by a method not much different from Starling's own, we arrived at quite a different figure. This fact we have attempted to explain. Finally we have described an entity which we hold to be more closely representative of mean systemic compression during life, and have shown how to arrive at it.     

Epoxy‐toughened,unsaturated polyester interpenetrating networks

A series of translucent interpenetrating polymer networks (IPNs) made of a reactive elastomer [linear (D) and branched (T) with varying molecular weights] (Jeffamine?), a commercially available epoxy (D.E.R. 331), and an unsaturated polyester (15:85 wt %) were prepared. DSC data indicated complete cure after 8 h at 90°C. DMTA data showed a single glass‐transition temperature (T_g) for all elastomer‐containing IPNs, an indication of homogeneity. As expected, all IPNs showed a decrease in T_g with incorporation of elastomer, from 16 to 114°C or lower, the largest decrease being with T‐5000. Izod impact strengths were increased by 28–44%, but with no apparent pattern among structure and molecular weight variations. In several cases the standard deviation of impact data increased significantly. Flexural data were measured using a three‐point bend test. The highest flexural modulus obtained was that which incorporated linear D‐2000 with a decrease of only 22% upon incorporation of the elastomer, whereas other compositions dropped up to 55% in flexural modulus. The strongest material obtained was that using D‐2000 with a flexural strength increase of 65% upon incorporation of the elastomer. Two of the three branched elastomer components showed flexural strength increases of about 53%, but one was only equal to the base polyester resin. TGA data were recorded for all IPNs and values compared well to that of the pure polyester resin, with the exception of T‐403, which showed a 20°C decrease, and D‐2000 with a 10°C decrease. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2283–2286, 2002