Analysis of the degree of precision of a computer-assisted dietary survey method

A computer-assisted method for the registration of food intakes in real time according to a concise and simple procedure was subjected to a series of controls in order to assess precision. The method employs the 'portion' of a composite dish as unit of measure. The constancy of the portion was tested. The results show that the recipes of the diet of a subject may be stored and utilized in deferred time without loss of precision: data to be recorded in real time are then very limited. The length of period of analysis was also studied. The time of investigation should not be shorter than two weeks to obtain precise information on the feeding habits of an individual subject, whereas for a group of subjects the diary of a single day provides information of sufficient precision.     

N-ω-Carbethoxypentyl-4-quinolones: A New Class of Leukotriene Biosynthesis Inhibitors

6-[(4-Quinolinyl)oxy]hexanoic acids and the corresponding esters were designed and synthesized as inhibitors of the production of arachidonic acid metabolites. The inhibitory activities were assayed in vitro by evaluation of serum leukotriene B₄ and thromboxane B₂ production. While all 6-[(4-quinolinyl)oxy]hexanoic acids and their esters proved to be inactive, the N-alkyl-4-quinolones, obtained as by-products in their synthesis, were found to be a new class of leukotriene biosynthesis inhibitors.     

Total cortisol,free cortisol,and growth hormone associated with brief social separation experiences in young macaques

Many behavioral, immunological, and physiological consequences of brief maternal separation in bonnet (Macaca radiata) and pigtail monkeys (Macaca nemistrina) have been documented. However, the impact of social separation on plasma cortisol and growth hormone is unknown for these particular species. In the present study, the behavioral and endocrinological consequences of a 2-week maternal separation in socially housed infant bonnet and pigtail monkeys were followed. In seven pairs (separated and matched control) of bonnet and six pairs of pigtail infants, plasma was obtained under baseline, separated, and reunion conditions twice weekly for the duration of the study. Blood samples were obtained from both infants of the pair in approximately 10 min. Plasma total cortisol, free cortisol, and growth hormone were measured in these samples. Focal animal behavioral observations were made on all subjects twice daily throughout the study period. In both species, total cortisol and free cortisol rose immediately following maternal separation in comparison to the matched nonseparated controls and returned to basal levels (e.g., that of matched non-separted controls) following reunion with the mother. In contrast, plasma growth hormone rose only in the pigtail infants over a time course that peaked around the time of reunion. Multiple regression techniques indicated for the first week of separation, in the separated but not control subjects, that mean plasma free and total cortisol was positively related to distress behaviors (vocalization and postural slouch) observed during this week and negatively related to social behaviors (play and proximity to others) noted during the same period. In contrast, plasma growth hormone was related to both species and sex of the subjects but unrelated to behavioral variables. © 1995 John Wiley & Sons, Inc.     

Photoinduced electron transfer in porphyrin-naphthyl pairs covalently and randomly bound to α-helical poly(L-lysine)

The photophysics of protoporphyrin-naphthyl (P-N) pairs covalently and randomly bound to the ε-amino groups of the side-chains of poly(L -lysine) (PL) were investigated by steady-state and time-resolved fluorescence measurements. The results indicate that quenching of excited naphthalene (λ_ex = 280 nm) chiefly occurs by interconversion to the triplet state when the polymeric matrix is in random coil (pH ≈ 7) and by intramolecular electron transfer from ground-state porphyrin, P → ¹N^*, when the polypeptide is in α-helical conformation (pH ≈ 11), the specific rate constant of the electron transfer being 3,1 · 10⁷ s^?1 (25°C). PNPL exhibits very little exciplex fluorescence, whatever the pH, suggesting both a reduced internal Brownian motion of the chromophores, owing to the amide bond in the substituted side-chains, and a relatively large average interprobe separation distance. This agrees with polarized fluorescence data and with the results of a conformational statistics analysis on the fully ordered PNPL, indicating that the average interchromophoric distance for which the electron transfer has the highest probability to occur is around 12 Å. The computational results allowed us to reproduce the experimental fluorescence decay curves and estimate the parameters governing the electron transfer process. Implications of these findings on the relaxation time of the heli-xcoil transition in PNPL are briefly discussed.     

Changes in Neutrophil Oxidative Potential in Patients Undergoing Cardiopulmonary Bypass with Polypropylene Hollow Fiber Oxygenators

Neutrophil oxidative metabolism, C3d and beta 2 microglobulin levels, were assessed in nine consecutive patients undergoing cardiopulmonary bypass surgery with polypropylene hollow fiber oxygenators for open cardiac operations. Generation of oxygen free radicals by neutrophils was measured as luminol-enhanced chemiluminescence after stimulation with opsonized Zymosan and phorbol myristate acetate. A significant increase in light emission was detected by using both of the chemiluminescence stimulators. Moreover, a remarkable and significant increase in C3d levels was found already at 10 min. Conversely minimal changes in levels of beta 2 microglobulin were detected during cardiopulmonary bypass surgery. These data suggest that the impact of the patient blood with the foreign surface of cardiopulmonary bypass results in activation of phagocyte cells with increased potential in oxygen consumption. These effects could be partially complement-mediated.     

Transitional progressive multiple sclerosis: MRI and MTI findings

Transitional progressive multiple sclerosis (MS) is quite an unusual form of presentation and course of the disease. A case with this progressive form is presented and brain MRI and MTI findings are discussed in relation to the possible insight they may provide for understanding the mechanisms that determine progressive disability in MS.     

Inhibition of leukocyte chemotaxis by serum factor in diabetes mellitus: selective depression of cell responses mediated by complement-derived chemoattractants

Rat neutrophil chemotactic responses to N-formyl-methionyl-leucyl-phenylalanine (FMLP), leukotriene (LT) B4, and lipopolysaccharide-activated serum (LPS-AS) were quantitatively assessed using the micropore filter system. Cells were suspended in either normal or diabetic rat serum for testing. Diabetic donor serum did not affect migration of neutrophils in a concentration gradient of the synthetic chemotactic agents. In contrast, the migratory responses to LPS-AS were significantly less than normal in this circumstance. Summation of effects was observed when FMLP and LPS-AS, or LTB4 and LPS-AS were simultaneously added to the test chamber, with cells suspended in normal serum. Suspended in diabetic rat serum neutrophils responded normally to the synthetic chemoattractants but the response to the activated serum was blocked. Cells previously incubated in the presence of diabetic donor serum then transferred to a culture medium for testing, presented reduced migratory responses to LPS-AS. Supramaximal, inhibitory concentrations of FMLP and LTB4, did not influence the response of neutrophils to LPS-AS. In vivo, suppression of cellular emigration to an inflamed area was observed from the early stages of the diabetic state. The inhibitory activity of chemotaxis in diabetes mellitus was previously reported to be associated with a protein factor in plasma of the animals. It is suggested that the inhibitory factor of chemotaxis in diabetes mellitus interacts with neutrophil receptors for complement-derived chemoattractants to induce blockade of cell-oriented locomotion either in vitro or in vivo.