Cytoanalysis of Pancreatic B-cells: Using an Avian Model, Mammalian Tissue Culture and Implications of Antisense Oligonucleotides Transfection

Calbindin-D28k (CaBP28K) is a vitamin D-dependent calcium-binding protein that may alter intracellular calcium ion levels, [Ca2+]i. This dissertation describes experiments done to gain an understanding of the potential role of CaBP28k in pancreatic B-cells in control of insulin secretion. The localization of CaBP28k and insulin in chicken pancreas are shown in Chapter 1. CaBP28k expression was found to be highest in ventral and dorsal lobes and lowest in splenic lobe. Insulin concentrations were distributed similarly among these lobes. Confocal microscopic studies demonstrated colocalization of insulin and CaBP28k in Bcells. These findings suggest a possible role for CaBP28k in chicken B-cells that could contribute to type 2 diabetes-like characteristics of chickens. Experiments done in Chapter 2 tested the effects of changing levels of glucose in pancreatic islets in vitro from transgenically derived CaBP28k-knockout (KO) and wildtype (WT) mice. CaBP28k-KO islets were exposed to increasing glucose concentrations from 2.8 mM to 30 mM, levels that mimic transition from fasting to hyperglycemic states. KO islets showed significantly greater elevations in [Ca2+]i as compared to WT. These experiments provide evidence that levels of CaBP28k could play a role in controlling Ca2+-mediated, glucose-induced insulin secretion in B-cells. In chapter 3 the effects of reduction of CaBP28k levels on genomic and nongenomic factors using CaBP28k-antisense oligonucleotides (AS-ON) transfection in a cultured pancreatic B-cell line (RIN1046-38 cells) are described. Complete inhibition of CaBP28k expression in transfection assays was achieved using 200 nM phosphorothioate-AS-ON (PS-AS-ON) as well as 20 nM propyne-AS-ON (PY-AS-ON). In addition, cDNA microarray analysis showed up-regulation of both vitamin D receptor (VDR) and calbindin-D9k mRNAs in PS-AS-ON-transfected RIN cells as compared to controls. Western blotting indicated VDR overexpression and calbindin-D9k expression in AS-ON-transfected cells. This study is the first demonstration of compensatory expression of calbindin-D9k in response to inhibition of CaBP28k in cultured B-cells. Insulin secretory responses of PS-AS-ON-transfected cells were greater than in controls. These findings suggest that B-cells synthesize an alternative protein, calbindin-D9k, to preserve calcium regulation when expression of CaBP28k is abolished. Additional studies are required to help in understanding possible interactions of calbindin-D9k, [Ca2+]i, and VDR in the AS-ON-transfected B-cells

Co-Application of Corticosterone and Growth Hormone Upregulates NR2B Protein and Increases the NR2B:NR2A Ratio and Synaptic Transmission in the Hippocampus

Objectives: This in vitro study aimed to investigate the possible mechanism underlying the protective effect of growth hormone (GH) on hippocampal function during periods of heightened glucocorticoid exposure. Methods: This study was conducted between January and June 2005 at the Joan C. Edwards School of Medicine, Marshall University, in Huntington, West Virginia, USA. The effects of the co-application of GH and corticosterone (CORT) were tested at different concentrations on the field excitatory postsynaptic potentials (fEPSPs) of the hippocampal slices of rats in two different age groups. Changes in the protein expression of N-methyl-D-aspartate receptor (NMDAR) subunits NR1, NR2B and NR2A were measured in hippocampal brain slices treated with either artificial cerebrospinal fluid (ACSF), low doses of CORT alone or both CORT and GH for three hours. Results: The co-application of CORT and GH was found to have an additive effect on hippocampal synaptic transmission compared to either drug alone. Furthermore, the combined use of low concentrations of GH and CORT was found to have significantly higher effects on the enhancement of fEPSPs in older rats compared to young ones. Both GH and CORT enhanced the protein expression of the NR2A subunit. Simultaneous exposure to low concentrations of GH and CORT significantly enhanced NR2B expression and increased the NR2B:NR2A ratio. In contrast, perfusion with CORT alone caused significant suppression in the NR1 and NR2B protein expression and a decrease in the NR2B:NR2A ratio. Conclusion: These results suggest that NMDARs provide a potential target for mediating the GH potential protective effect against stress and age-related memory and cognitive impairment

A NEW SMALL POTATO PLANTER FOR EGYPTIAN AGRICULTURE

Reducing the tuber period for potato plants by planting previously grown sprouts is a new technique. Applying this new agricultural methodology requires modification of the potato planter. The theoretical analysis was carried out to obtain information that can help avoid tuber damage during feeding and until it exits the feeding system. Starting from these considerations, a new potato planter with a spoon-based feeding system was designed and built. The tests conducted verified that the new system performed well when dividing tuber pieces into rows: considering the best growth spacing for potatoes is 20÷30 cm, the new system has a 68% distribution versus the 50,62 % of the old one. The tubers' spacing in rows are evaluated based on tuber voids and tuber doubles. The results show that there is no difference between the two systems' configurations, while a general consideration about our machine is that it is better at managing small tuber pieces. The void ratios are largely valid within the range of 0.4 up to 0.8 m/s of planted speeds; moreover, the results revealed that the tuber doubles decrease by increasing planting speed and vice versa with tuber voids. The quality of the potatoes planted is evaluated using the Shatter Index (SI %), which shows how the new configuration is more delicate with the tuber pieces (1.5 % against 17.5 % at 10 rpm or 46 % against 94 % at rpm 20). The new configuration could be an interesting improvement for potato quality and Egyptian potato production

Vibration analysis influence during crisis transport of the quality of fresh fruit on food security

Mechanical damage of agriculture produce is a major problem in the harvest and post-harvest chain.  This damage could cause huge economic loss.  In addition, it could lead to serious food safety concerns.  Several cases of foodborne illness have been traced to poor or unsanitary postharvest practices.  Escherichia coli (E. coli) O157:H7, Salmonella, Shigella, Listeria, Cryptosporidium, Hepatitis, and Cyclospora are among the diseases and disease-causing organisms that have been associated with fresh fruits and vegetables.  Measurements of mechanical characteristics of agricultural products under different static and dynamic loads should help in predicting the type and magnitude of mechanical injuries which will help in minimizing losses and improve the safety the produce.  In the current study, we examined the parameters essential for fruit package processes.  Fruits were exposed to random excitation( is excited by combination of single- sinusoidal signal and a broad band stochastic single and compared to pure stochastic excitation) by using robust techniques EFDD enhanced frequency domain to harmonic excitation.  Six vibration modes were identified in the frequency range of 0-1.6 kHz by two techniques FDD & EFDD.  The paper-wrap and foam-net cushioning materials interaction is also studied.  Damage identification technique has been applied to determine the integrity of the structure.  Nearly all the examined fruit showed deterioration due to vibro-pressure and friction stresses mainly consisting of translucent or darkened bruises and streaks.  Results obtained from test without cushioning materials have been correlated with the package of paper-wrap cushioning materials and foam-net cushioning materials.     Keywords: vibration analysis, crisis transport, quality, damage, food safet

Development of chitosan-glucose and chitosan-citric complexes edible coating to improve tomatoes post-harvest quality

 The effect of different shrimp chitosan molecular weights as well as shrimp chitosan complexes (chitosan-glucose and chitosan-citric) on the quality characteristics of the stored (at 7°C±2°C and 90% RH) tomato fruits (Lycopersicum esculentum) was investigated.  Coating tomatoes with high molecular weight chitosan (H.M.C.G) significantly improved firmness and weight loss.  The lowest weight loss was found in high molecular weight chitosan-glucose (H.M.C.G) treatment followed by the fruits coated with high molecular weight chitosan (HMC) and then uncoated tomato fruits.  Both molecular weights was clear on retarding the total acidity loss especially for stored tomato fruit coated with low molecular weight chitosan, while control tomatoes exhibited a larger reduction (p ≤ 0.05) in total acidity over storage.  Meanwhile, the increasing of cold storage time significantly (p ≥ 0.05) increased the pH in all uncoated and coated tomatoes.  Generally, no significant (P > 0.05) difference was observed in pH, titratable acidity and total soluble solids (T.S.S.) as well as sensory attributes among the tomato fruits coated with chitosan, chitosan citric and chitosan glucose.  Meanwhile, the fruits coated with low molecular weight chitosan had a higher (p ≥ 0.05) T.S.S. compared with that coated by the high molecular weight chitosan.   Keywords: chitosan, edible coating, tomatoes, firmness and weight loss

Tonsilofaringita cronica

Catedra ORL, USMF ,,Nicolae Testemitanu”Tonsilo chronic pharyngitis is a current problem of otorhinolaryngology. This work describes the signs of the disease subjective and objective. The authors conclude that tonsilo pharyngitis is a new nosological form that needs to be included in the nomenclature of diseases. Tonsilofaringita cronică prezintă o problemă actuală a otorinolaringologiei. În lucrare se descriu semnele subiective şi obiective ale acestei afecţiuni. Autorii concluzionează că tonsilo faringita este o formă nozologică nouă şi necesită de a fi inclusă în nomenclatorul afecţiunilo

Generator Cooling Fan Vibrational Problems: A Design and Operational Case in Jordan

This project covers certain types of rotor generator vibrational problem, including both conventionally-cooled (indirect copper cooling) windings and direct cooled copper windings as well as those with spindle and body mounted retaining rings. The options for rewinding, modifying, or upgrading are provided for each case type as encountered in the Jordan Petroleum Refinery. Generally; when dealing with generator rotors, problems like oversizing, misalignment, rotor imbalance, off-design operation, lubrication problems, shaft seals, cavitation, balancing system, and vibration are encountered. Methods of resolving vibration problem diagnosis were discussed using different techniques like vibration design analysis which will enhance root cause problems. We have proposed different maintenance best practice like rotor dynamic balance, appropriate operation, seals selection, and lubricant selection. At the end we have proposed a design solution appropriate for failure prevention using rotor balancing after rework or modifications