Preparation of cold water-soluble potato starch and its characterization.

Alcoholic-alkaline treatment of starch results in granular cold water-soluble starch. The nature of structural alterations occurred in starch due to the treatment is however relatively vague. Potato starch was treated at various alcoholic-alkali conditions and subjected to light microscopy, Fourier transform infrared (FTIR) spectroscopy and X-ray diffractometry. Alcoholic-alkaline treatment increased the solubility of starch in a temperature-dependant manner. The treated starch suspension was also more turbid than that of native counterpart at all concentrations, due probably to either the presence of higher number of water-soluble granules or leaching of amylose during alkalization. Alcoholic-alkali treating of starch did not disintegrate the granular assembly; albeit, decreased the crystalinity. Both native and treated starches showed the B-type pattern in X-ray diffractometry. FTIR spectroscopy revealed that characteristic peaks of hydroxyl groups were of low transmittance in spectrum of treated starch compared with that of native counterpart implying in participation of hydroxyl groups in interactions with modifying agents.

An attempt to cast light into starch nanocrystals preparation and cross-linking.

Potato starch was hydrolyzed with 2.2 or 3.7 M hydrochloric acid in order to obtain the nanocrystals which afterwards were chemically cross-linked with sodium hexametaphosphate. The stronger acidity resulted in smaller nanocrystals with mean size of 48 nm in a shorter time. X-ray diffraction confirmed the dominant crystalline nature of particles and Fourier transform infrared spectroscopy suggested the presence of lower number of free hydroxyl groups in nanocrystals after cross-linking. Starch nanocrystals showed two distinctive differential scaning colorimetry endotherms at 26 and 125 °C, attributed to destruction of nanocrystals lattice and moblizing of each nanocrystal's structure, respectively. Cross-linking resulted in a tenacious spatial arrangement of nanocrystals, strengthening the crystals lattice against phase transitions induced by heating. Scanning electron microscopy images confirmed the particle size measured for nanocrystals by light scattering. Atomic force microscopy topographic images suggested that starch nanocrystals were originated from small amylopectin blocklets in granular assembly of starch.

Effects of maternal nicotine exposure on expression of laminin alpha 5 in lung tissue of newborn.

Maternal smoking has been clearly demonstrated to be associated with increased health problems in infants and children. Nicotine is the chemical substance with high level of toxicity. It crosses through the placenta and accumulates in the developing organs of fetus. Previous investigation indicated that maternal nicotine exposures induce decreased fibronectin expression in lung parenchyma. In this study, the effect of maternal nicotine exposure on laminin expression of the newborn mice lungs has been evaluated. Female pregnant Balb/C mice were divided randomly in to four groups as fallow: Experimental group 1 (Exp D1); was received 3 mg kg(-1) nicotine intra peritoneal injection (IP) from gestational day 7 (GD7) to the last day of pregnancy, Experimental group 2 (Exp D14); was received 3 mg kg(-1) nicotine from GD7 to postnatal day 14, Groups 3 and 4; as sham control groups (Sha-Con) were received the same volume (3 mg kg(-1)) of normal saline parallel to experimental groups. At the end of exposure times, all of newborns were anesthetized; their lungs were removed and prepared for immunohistochemical method and real-time polymerase chain reaction. The finding indicated that laminin alpha 5 (Lama5) mRNA expressions in the lung of newborn in the nicotine treated Exp D1 decreased by 0.63 fold but increased in Exp D14 by 1.57 fold comparing to Sh-Con groups. Lama5 immunoreactivity was not similar in different parts of the lungs including alveoli and bronchiole, having a significant increase in the experimental groups in contrast to the Sh-Con groups. However, increase in immunoreactivity observed more in Exp D14. Immunoreactivity intensity in small vessels of all experimental groups was not significantly different. These data also indicate that maternal nicotine exposure may induce abnormal laminin expression which may cause defects in lung function during life time.

Pattern of laminin expression during kidney morphogenesis in Balb/c mice.

Basement membrane of glomerular mesangium (BMG) is one of important components which play a key role to support of the capillary loops in a renal glomerulus and completeness of BMG due to interaction of ureteric bud and metanephric mesenchyme during glomerulogenesis. As laminin contribute in extra cellular matrix and especially in basement membrane, the aim of the present study was to demonstrate the distribution of this molecule so, in this investigation specific antibody against laminin have been used in light microscopy to study development of BMG of fetal and postnatal mouse glomerular mesangium. Female inbred Balb/c mice were selected and were kept under normal condition and finding vaginal plug was assumed as day zero of pregnancy. Two pregnant mice were sacrificed by cervical dislocation in one of gestational days 13-18, respectively and their fetuses were fixed, serially sectioned and by using antibody against laminin in BMG were carried out. The same process was used for kidneys preparation at 15 postnatal days. Present data revealed that laminin showed weak reaction on day 14 of gestation. The amount of laminin increased continuously until next days of fetal life and primary of 10 days postnatal in BMG. After this period, laminin reaction did not show significant change in newborns. These data indicate that laminin appears just during the glomerulogenesis and because of continuity with vasculature which is required for Extra Cellular Matrix (ECM) and glomerular endothelial cell differentiation, laminin, is the one of major structural proteins in BMG.