Vasoactive intestinal peptide (VIP) cells in the pancrease and gastro-intestinal mucosa. An immunohistochemical and ultrastructural study.

Using antibodies against pure porcine VIP in immunoperoxidase and immunofluorescence tests, VIP-immunoreactive cells have been detected in the pancreas-especially in the islets-and gastrointestinal mucosa of the dog, guinea-pig and man. VIP immunoreactive cells were widely distributed in these tissues, never being numerous at any site. Some parallelism has been noted between such cells and ultrastructurally identified D1 cells fo the pancreas and gastrointestinal mucosa. The presence of VIP cells in normal pancreas may help explain the occurrence of pancreatic endocrine tumors producing VIP.     

Immobilized Sclerotinia sclerotiorum invertase to produce invert sugar syrup from industrial beet molasses by product

The fungus Sclerotinia sclerotiorum produces invertase activity during cultivation on many agroindustrial residues. The molasses induced invertase was purified by DEAE-cellulose chromatography. The molecular mass of the purified enzyme was estimated at 48 kDa. Optimal temperature was determined at 60 °C and thermal stability up to 65 °C. The enzyme was stable between pH 2.0 and 8.0; optimum pH was about 5.5. Apparent K_m and V_max for sucrose were estimated to be respectively 5.8 mM and 0.11 μmol/min. The invertase was activated by β-mercaptoethanol. Free enzyme exhibited 80 % of its original activity after two month’s storage at 4 °C and 50 % after 1 week at 25 °C. In order to investigate an industrial application, the enzyme was immobilized on alginate and examined for invert sugar production by molasses hydrolysis in a continuous bioreactor. The yield of immobilized invertase was about 78 % and the activity yield was 59 %. Interestingly the immobilized enzyme hydrolyzed beet molasses consuming nearly all sucrose. It retained all of its initial activity after being used for 4 cycles and about 65 % at the sixth cycle. Regarding productivity; 20 g/l of molasses by-product gave the best invert sugar production 46.21 g/day/100 g substrate related to optimal sucrose conversion of 41.6 %.     

Effects of Bacterial Inoculation to Immobilize Nickel in Wheat Grown on Ni-Contaminated Soil

Abstract

Plant growth stimulating bacteria are very effective in immobilization of metals and reducing their translocation in plants through precipitation, and adsorption. A pot experiment was conducted to investigate the effectiveness of chitosan- and hematite-modified biochar and bacterial inoculations on the immobilization of nickel (Ni) in polluted soil under wheat cultivation. Application of modified biochars and inoculation with Pseudomonas putida significantly increased both wheat root and shoot dry matter yields but decreased Ni phytoextraction efficiency. The Ni concentration, translocation factor and uptake in wheat shoot and root significantly decreased the application of either modified or unmodified biochars. Bacterial inoculation significantly decreased mean translocation factor and also root and shoot concentration and the uptake Ni in the shoot. Chitosan-modified biochar was the most influential treatment in decreasing Ni uptake by wheat followed by P. putida inoculation treatment. The results demonstrated positive effects of chitosan modified biochar and inoculation with P. putida in increasing dry matter yield and decreasing Ni uptake in wheat grown on Ni-contaminated soil. According to the results of present study, modified biochars application and bacterial inoculation are influential treatments which prevent Ni toxicity probably.     

Does aging affect the intestinal transport of riboflavin?

Riboflavin deficiency has been reported in older individuals. The cause of this deficiency is not know but could include a decrease in the intestinal absorptive capacity for riboflavin. Therefore, we examined the intestinal absorption of riboflavin in young (3 month) and old (26 month) rats. We used in vitro jejunal everted sacs. The kinetic parameters of riboflavin absorption disclosed apparent Km of 0.37 and 0.43 microM and Vmax of 37 and 38 pmole/g initial tissue wet wt/20 min in young and old rats, respectively. These data do not demonstrate an aging associated change in the intestinal transport capacity for riboflavin. If these results are extrapolated to man, it would mean that the deficiency of riboflavin found in the elderly is not due to its intestinal malabsorption. Therefore, other mechanisms must be sought to account for the deficiency of riboflavin seen in the elderly.     

Percutaneous transvenous retrieval of intracardiac port-a-cath catheter fragment: a case report

A female patient, 36 years of age, with a metastasised left breast cancer received several courses of chemotherapy for aggressive local tumour growth and multiple metastatic activity. In the current patient, surgical ablation of the left breast was carried out. Also loco-regional radio-therapy was conducted. To facilitate the administration of chemotherapy courses and prevent thrombophlebitis a vascular access port (port-a-cath) was surgically inserted via the right subclavian vein. After a few successful administrations of chemotherapeutic drugs the vascular port stopped functioning. It was demonstrated that a detached catheter fragment had dislodged into the right ventricle. Successful percutaneous, transvenous removal of the entrapped catheter fragment by the Gooseneck retrieval loop snare from the right ventricle was performed via the right femoral vein access. The procedure was uncomplicated and the patient tolerated the procedure well.     

Pulmonary vasodilator responses to vasoactive intestinal peptide in the cat

We investigated the effects of vasoactive intestinal peptide (VIP) in the feline pulmonary vascular bed under conditions of controlled pulmonary blood flow when pulmonary vascular tone was at base-line levels and when vascular resistance was elevated. Under base-line conditions, VIP caused small but significant reductions in lobar arterial pressure without affecting left atrial pressure. Decreases in lobar arterial pressure in response to VIP were greater and were dose related when lobar vascular resistance was increased by intralobar infusion of U 46619, a stable prostaglandin endoperoxide analogue. Acetylcholine and isoproterenol also caused significant decreases in lobar arterial pressure under base-line conditions, and responses to these agents were enhanced when lobar vascular tone was elevated. Moreover, when doses of these agents are expressed in nanomoles, acetylcholine and isoproterenol were more potent than VIP in decreasing lobar arterial pressure. Responses to VIP were longer in duration with a slower onset than were responses to acetylcholine or isoproterenol. Pulmonary vasodilator responses to VIP were unchanged by indomethacin, atropine, or propranolol. The present data demonstrate that VIP has vasodilator activity in the pulmonary vascular bed and that responses are dependent on the existing level of vasoconstrictor tone. These studies indicate that this peptide is less potent than acetylcholine or isoproterenol in dilating the feline pulmonary vascular bed and that responses to VIP are not dependent on a muscarinic or beta-adrenergic mechanism or release of a dilator prostaglandin.     

Ischemia reperfusion dysfunction changes model-estimated kinetics of myofilament interaction due to inotropic drugs in isolated hearts

Background  

The phase-space relationship between simultaneously measured myoplasmic [Ca²⁺] and isovolumetric left ventricular pressure (LVP) in guinea pig intact hearts is altered by ischemic and inotropic interventions. Our objective was to mathematically model this phase-space relationship between [Ca²⁺] and LVP with a focus on the changes in cross-bridge kinetics and myofilament Ca²⁺ sensitivity responsible for alterations in Ca²⁺-contraction coupling due to inotropic drugs in the presence and absence of ischemia reperfusion (IR) injury.