14C]leucine incorporation into proteins of pancreatic juice in rats fed soya-bean flour

1. The effect of a diet containing a trypsin inhibitor on the incorporation of radioactively labelled leucine into the pancreatic proteins secreted during stimulation with cholecystokinin-pancreozymin (CCK) was studied in rats. 2. The total output of protein was significantly greater in the rats given raw soya-bean flour (RSF) compared with those given heat-inactivated soya-bean flour (HSF) (controls) in response to the sub- and supramaximal stimulation with CCK, but similar responses were obtained to maximal stimulation with CCK. Total protein output decreased continuously with time after reaching peak values at 90--120 min after the start of stimulation with CCK. 3. The total output of radioactively labelled protein in RSF-fed rats was not different from that of the controls with sub- and supramaximal dose rats of CCK, but was significantly lower than that of the controls in response to the dose rate of CCK which produced maximal rates of pancreatic secretion. 4. The specific activity of radioactively labelled protein increased continuously, while the output attained a constant rate during stimulation with all doses of CCK. 5. We concluded that feeding the trypsin inhibitor-containing diet led to increased secretion of stored pancreatic protein, while secretion of newly synthesized protein was not altered. During the course of prolonged stimulation with CCK, irrespective of diet, there was increasing secretion of the newly synthesized protein compared with the pre-existing stored proteins of the pancreas, it was unable to compensate for the decreased secretion of pre-formed protein.     

Ability of fractionated petroleum refinery effluent to elicit cyto- and photocytotoxic responses and to induce 7-ethoxyresorufin-O-deethylase activity in fish cell lines

The ability of fractionated petroleum refinery effluent to cause cellular responses in fish cell lines was evaluated. The cellular responses, which included direct and indirect cytotoxicity, photocytotoxicity and induction of 7-ethoxyresorufin-O-deethylase (EROD) activity, may potentially be linked to sublethal effects observed in effluent-exposed fish and fish larvae. In order to be able to quantify cellular responses rapidly, microtitre plates were used along with fluorescent probes. For the quantification of cyto- and photocytotoxicity, the fluorescent probes were alamar Blue and carboxyfluorescein diacetate acetoxymethyl ester (CFDA-AM), which monitor metabolic activity and cell membrane integrity, respectively. EROD activity was measured as the rate of conversion by EROD of the substrate 7-ethoxyresorufin to its fluorescent product, resorufin. Effluent from an Ontario refinery was fractionated into aqueous and particulate phase. As well, a solid phase extract (SPE) was used to prepare concentrated effluent for testing in the cell lines. The effluent was able to elicit all of the responses of interest although significant cyto- and photocytotoxicity required effluent equivalent concentrations above 100% effluent and could only be revealed upon exposure of cells to the SPE concentrated effluent. Based on their retention on C18, the cytotoxicants are likely to be non-polar to moderately polar chemicals. The presence of polar compounds affecting cellular metabolism was indicated by the responses of exposed cells to a 90% aqueous phase effluent. In contrast to cyto- and photocytotoxicity, EROD induction occurred at effluent equivalent concentrations well below 100% effluent and was elicited by the SPE and the particulate fraction thereby suggesting that most EROD-inducers were particle-bound. Among other applications, the described techniques could help to determine the source of causative agents of sublethal effects in the refining process.     

Impact of air humidity in industrial heating processes on selected quality attributes of bread rolls

The object of this research was to study the real time percent humidity of the air and consequently to analyze this humidity influences on bread rolls. An industrial baking process was visualised by the use of a high-temperature humidity sensor to measure the level of percent humidity of the air (V% H₂O) in relation to the different H₂O-steam amounts (SA). In this study H₂O-SA from 0 to 3.256 L(H₂O) m⁻³ of the oven volume were used. After steaming the results of gas moisture without product (GMWoP) showed a higher maximum (approx. 5%) of the percent humidity of the air than the gas moisture with product (GMWP). The trials reveal that the presence of products (bread rolls) is a factor in attaining an increase in the percent humidity of the air which influences product quality. Baking with adequate percent humidity of the air bread roll volume increased by 20% compared to trials without steam. New methods were used to quantify product parameters like crust thickness, compression-force and crispness and to find out correlations with the area under the GMWP curve (auc). Strongest correlations with auc GMWP were found for mean and maximum compression-force. Furthermore, it was shown that the increase in crust thickness, lightness and colour change is mutually dependent on an increase change in the total GMWP.     

Affective dimensions of odor perception: A comparison between Swiss, British, and Singaporean populations.

Do affective responses to odors vary as a function of culture? To address this question, we developed two self-report scales in the United Kingdom (Liverpool: LEOS) and in Singapore (city of Singapore: SEOS), following the same procedure as used in the past to develop the Geneva Emotion and Odor Scale (GEOS: Chrea, Grandjean, Delplanque et al., 2009). The final scales were obtained by a three-step reduction of an initial pool of 480 affective terms, retaining only the most relevant terms to describe odor-related subjective affective states and comprised of six (GEOS) or seven affective dimensions (LEOS and SEOS). These included dimensions that were common to the three cultures (Disgust, Happiness Well-being, Sensuality Desire, and Energy), common to the two European samples (Soothing Peacefulness), and dimensions that were culture specific (Sensory Pleasure in Geneva; Nostalgia and Hunger Thirst in Liverpool; Intellectual Stimulation, Spirituality, and Negative Feelings in Singapore). A comparative approach showed that the dimensional organization of odor-related affective terms in a given culture better explained data variability for that culture than data variability for the other cultures, thus highlighting the importance of culture-specific tools in the investigation of odor-related affect. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The role of polymorphonuclear leukocytes in the resistance to cutaneous Leishmaniasis

The massive infiltration by polymorphonuclear leukocytes (PMN) soon after skin infection with Leishmania major suggests that PMN could participate in reducing parasite load and controlling the spreading of leishmanial infection. Yet, direct evidence for the participation of PMN in host defense against L. major was lacking. We investigated L. major infection in susceptible and resistant mice treated with the monoclonal (mAb) antibody RB6-8C5 that depletes the population of mature neutrophils and eosinophils. Both BALB/c and C57BL/6 mice depleted of PMN show accelerated parasite spreading and more severe footpad swelling than similarly infected untreated mice. In addition, significant higher parasite numbers were found in the lesion draining lymph nodes from PMN-depleted C57BL/6 mice. Histopathological analysis of the paw confirmed neutrophils containing ingested parasites as the dominant cell type in the infiltrate of the first days after infection and the nearly absolute neutrophil depletion in mAb-treated mice. Our data show the importance of PMN in early control of parasite load and parasitism spreading in cutaneous leishmaniasis.     

Resistance to apoptosis and elevated expression of Bcl-2 in clonally expanded CD4+CD28- T cells from rheumatoid arthritis patients

Patients with rheumatoid arthritis have a subset of CD4+ T lymphocytes that are characterized by a defect in CD28 expression. CD4+CD28- T cells frequently undergo clonal expansion in vivo. These clonotypes include autoreactive cells and persist over many years. The clonogenic potential and longevity of these T cells could be related to an altered response to apoptosis-inducing signals. To explore this possibility, CD4+CD28- T cell lines and clones were examined for their response pattern to stimuli inducing physiologic cell death. CD4+CD28- T cells were found to be resistant to apoptosis upon withdrawal of the growth factor, IL-2. To examine whether the altered sensitivity to this apoptotic signal was correlated with the expression of proteins of the bcl-2 family, the expression of bcl-2, bcl-x, and bax proteins was determined. CD28+ and CD28-CD4+ T cells could not be distinguished by the levels of bax or bcl-xL protein; however, CD4+CD28- T cells expressed higher amounts of bcl-2 protein than did CD4+CD28+ T cells. The increased bcl-2 expression in CD4+CD28- T cells was relatively independent of signals provided by exogenous IL-2. In CD28-deficient CD4+ T cells, bcl-2 was not significantly up-regulated by the addition of exogenous IL-2 and was maintained despite IL-2 withdrawal, as opposed to CD28-expressing CD4+ T cells. We propose that CD4+CD28- T cells are characterized by a dysregulation of the survival protein, bcl-2, which may favor the clonal outgrowth of autoreactive T cells and thus contribute to the pathogenesis of rheumatoid arthritis.     

Effects of fractionated abdominal irradiation on small intestinal motility--studies in a novel in vitro animal model

Disordered small intestinal motility occurs frequently during acute radiation enteritis. However, the characteristics and time course of the motor dysfunction are poorly defined. These parameters were assessed in a novel animal model of radiation enteritis. Ileal pressures were recorded in vitro with perfused micromanometric catheter using an arterially perfused ileal loop in 22 ferrets following fractionated abdominal irradiation (9 doses 2.50 Gy thrice weekly for 3 weeks). Tissue damage was graded histologically. Studies were performed 3 to 29 days after irradiation. Tissue from 7 control animals was also studied. All treated animals developed diarrhoea. Histology showed changes consistent with mild to moderate radiation enteritis. Following irradiation, there was an initial increase in frequency followed by a non-significant reduction in the frequency, but not the amplitude of ileal pressure waves. The frequency of pressure waves showed an inverse relationship with time after radiation (r = -0.634, p < 0.002). There was no relationship between motility and histology. We conclude that abdominal irradiation is associated with a time-dependent reduction in ileal motility which does not correlate with light microscopic changes.     

Low molecular weight dermatan sulfate as an antithrombotic agent. Structure-activity relationship studies

A structure-activity relationship of low molecular weight dermatan sulfate was undertaken to understand better this new non-heparin, glycosaminoglycan-based antithrombotic agent. A dermatan sulfate prepared from bovine intestinal mucosa [average molecular weight (MWavg) 25,000], and currently in clinical trials as an antithrombotic agent, was used in this study. Dermatan sulfate was partially depolymerized using hydrogen peroxide and copper(II) as catalyst to MWavg 5600 to obtain a low molecular weight dermatan sulfate. This low molecular weight dermatan sulfate was then fractionated by gel permeation chromatography to obtain four subfractions having MWavg 7800, 5500, 4200 and 1950. The dermatan sulfate, low molecular weight dermatan sulfate and its subfractions showed substantially different optical rotations. The 1H-NMR spectroscopic analysis of dermatan sulfate samples showed some differences including increased content of GalpNAc4S6S residues and improved resolution in ring resonances for low molecular weight dermatan sulfate fractions, primarily the result of reduced molecular weight and lowered heterogeneity. Saccharide compositional analysis relied on chondroitin ABC lyase treatment followed by capillary electrophoresis. Polyacrylamide gel-based oligosaccharide mapping was also performed by treating dermatan sulfate samples with chondroitin B, AC and ABC lysases. These analyses showed increased amounts of sulfation as the MWavg decreased. In vitro bioassay showed maximum anti-Xa activity in the 4.2 kDa fraction and maximum heparin cofactor II-mediated anti-IIa activity in the 5.5 kDa fraction. The in vivo antithrombotic activity of these fractions was measured using a modified Wessler stasis thrombosis model. The 4.2 kDa fraction showed greater antithrombotic activity than the other low molecular weight dermatan sulfate fractions, dermatan sulfate, and low molecular weight dermatan sulfate. This enhanced activity may result from several structural features of the 4.2 kDa fraction including: a high content of 4,6- and 2,4-disulfated disaccharide sequences; the requirement of specific chain length; a change in the ratio of iduronic to glucuronic acid; and the presence of chondroitin ABC lyase resistant material.