Evaluation of a teaching program of nutrition in agronomy

The purpose of this study was to evaluate a set of teaching materials on food, nutrition and agriculture, adapted at the Institute of Nutrition and Food Technology (INTA), University of Chile, within the scope of a project with AID and the School of Agronomy of the Chilean Catholic University (U. C.) aimed at incorporating the teaching of human nutrition into the curriculum of Latin American agronomists. A one semester course (54 hours) was given to 22 students of the 7th semester of Agronomy and two Ecuatorian agronomists (with AID scholarships). A set of knowledge evaluation instruments was applied at the beginning and at the end of the course. A total of 83.3% of the students passed the final examination (with more than 75% of correct answers). The difference between the initial and final performance was highly significant (p less than 0.001). According to the students' and teachers' opinions, the general textbook and the teachers book contributed effectively to meet the learning objectives whereas the students handbook needed some modifications. In conclusion, the program is an important contribution to the education of agronomists in a new conception of their role in regard to improvement of the nutritional status and quality of life of the rural population. With a few minor modifications, a final version to be used in the countries of the Region, shall soon become available.     

In vitro gas production profiles and fermentation end‐products in processed peas,lupins and faba beans

BACKGROUND: An experiment was carried out to establish whether using a pre‐compacting device (expander) changes the contribution of dry matter (DM) and degradative behaviour of peas, lupins and faba beans over the different fractions (non‐washable fraction, NWF; insoluble washable fraction, ISWF; soluble washable fraction, SWF). Samples of the entire concentrate ingredients (WHO ingredients) and their different fractions (NWF, ISWF and SWF) were subjected to three processes (Retsch milling, R; expander treatment, E; expander‐pelleting, EP) and their fermentation characteristics were evaluated using an in vitro gas production technique. RESULTS: In peas and faba beans, both the E and EP processes increased the size of the NWF (P < 0.05) and decreased the size of the SWF compared with the R process. The maximum fractional rate of gas production in the first phase of fermentation was higher in the E and EP samples than in the R samples (P < 0.05). In lupins and faba beans the E and EP processes shifted the pattern of fermentation towards a more glucogenic fermentation, as represented by a lower non‐glucogenic to glucogenic ratio (NGR). Ammonia production (NH₃‐N) in the E and EP samples was significantly (P < 0.05) lower than that in the R samples. CONCLUSION: It is concluded that the E and EP processes provide a certain level of protection against ruminal breakdown to dietary protein and shift the pattern of fermentation towards a more glucogenic fermentation. Copyright © 2008 Society of Chemical Industry     

The cholecystokinin-A receptor mediates inhibition of food intake yet is not essential for the maintenance of body weight

Food intake and body weight are determined by a complex interaction of regulatory pathways. To elucidate the contribution of the endogenous peptide cholecystokinin, mice lacking functional cholecystokinin-A receptors were generated by targeted gene disruption. To explore the role of the cholecystokinin-A receptor in mediating satiety, food intake of cholecystokinin-A receptor-/- mice was compared with the corresponding intakes of wild-type animals and mice lacking the other known cholecystokinin receptor subtype, cholecystokinin-B/gastrin. Intraperitoneal administration of cholecystokinin failed to decrease food intake in mice lacking cholecystokinin-A receptors. In contrast, cholecystokinin diminished food intake by up to 90% in wild-type and cholecystokinin-B/gastrin receptor-/- mice. Together, these findings indicate that cholecystokinin-induced inhibition of food intake is mediated by the cholecystokinin-A receptor. To explore the long-term consequences of either cholecystokinin-A or cholecystokinin-B/gastrin receptor absence, body weight as a function of age was compared between freely fed wild-type and mutant animals. Both cholecystokinin-A and cholecystokinin-B/gastrin receptor-/- mice maintained normal body weight well into adult life. In addition, each of the two receptor-/- strains had normal pancreatic morphology and were normoglycemic. Our results suggest that although cholecystokinin plays a role in the short-term inhibition of food intake, this pathway is not essential for the long-term maintenance of body weight.     

Intraoperative arthrography and the Ilizarov technique. Role in the correction of paediatric deformity and leg lengthening

We performed intraoperative arthrography of the knee in 12 children with congenital short femur, Blount's disease or Ollier's disease in whom the Ilizarov technique was used for correction of deformity, leg lengthening or both. In each case, arthrography revealed a joint surface considerably different from that assumed from plain radiographs, and resulted in a change in the placement of our reference wires before application of the frame. This gave significant improvement in the mechanical axis obtained at the time of removal of the frame. The technique is safe, cheap and easy to perform. It is a useful adjunct to the application of the Ilizarov frame when used for complex lengthening and correction of deformity in the leg.     

Volatile flavour components of dalieb (Borassus aethiopum L.)

The volatile components of dalieb fruit have been investigated by capillary column gas chromatography/mass spectrometry. The main components were C1 to C4 aliphatic alcohols and the corresponding acids together with esters derived from them. Acetic acid and ethanol were particularly abundant, the fruit pulp containing approximately 0.1% of each compound. Other volatiles present included the unsaturated ketone 6-methyl-5-heptene-2-one, the corresponding alcohol and the terpene, geranyl acetone.     

Cleavage of single strand RNA adjacent to RNA-DNA duplex regions by Escherichia coli RNase H1

RNase H1 from Escherichia coli cleaves single strand RNA extending 3' from an RNA-DNA duplex. Substrates consisting of a 25-mer RNA annealed to complementary DNA ranging in length from 9-17 nucleotides were designed to create overhanging single strand RNA regions extending 5' and 3' from the RNA-DNA duplex. Digestion of single strand RNA was observed exclusively within the 3' overhang region and not the 5' overhang region. RNase H digestion of the 3' overhang region resulted in digestion products with 5'-phosphate and 3'-hydroxyl termini. The number of single strand RNA residues cleaved by RNase H is influenced by the sequence of the single strand RNA immediately adjacent to the RNA-DNA duplex and appears to be a function of the stacking properties of the RNA residues adjacent to the RNA-DNA duplex. RNase H digestion of the 3' overhang region was not observed for a substrate that contained a 2'-methoxy antisense strand. The introduction of 3 deoxynucleotides at the 5' terminus of the 2'-methoxy antisense oligonucleotide resulted in cleavage. These results offer additional insights into the binding directionality of RNase H with respect to the heteroduplex substrate.