Histidine decarboxylase (HDC) synthesizes histamine from histidine in mammals. To evaluate the role of histamine, we generated HDC-deficient mice using a gene targeting method. The mice showed a histamine deficiency and lacked histaminesynthesizing activity from histidine. These HDC-deficient mice are viable and fertile but exhibit a decrease in the numbers of mast cells while the remaining mast cells show an altered morphology and reduced granular content. The amounts of mast cell granular proteases were tremendously reduced. The HDCdeficient mice provide a unique and promising model for studying the role of histamine in a broad range of normal and disease processes. ß
BAL5788 is the water-soluble prodrug of BAL9141, a novel broad-spectrum cephalosporin with potent bactericidal activities against methicillin-resistant Staphylococcus aureus (MRSA) and penicillin-resistant Streptococcus pneumoniae. We investigated the safety and pharmacokinetics of BAL5788 in a double-blind, single-ascending-dose study with 40 healthy male subjects. The subjects were randomized to receive placebo (n ؍ 2 subjects per dose) or BAL5788 (n ؍ 6 subjects per dose) as a 200-ml intravenous infusion over 30 min. The BAL5788 doses used were 125, 250, 500, 750, and 1,000 mg (BAL9141 equivalents). All doses were well tolerated, with no severe or serious adverse events (AEs). The most frequent AE was taste disturbance. No electrocardiographic abnormalities and no trends or clinically significant changes in laboratory parameters or vital signs were observed. The maximum concentration of drug in serum and the area under the concentrationtime curve for BAL9141 were dose proportional over the dosing range. The elimination half-life of BAL9141 was about 3 h. The volume of distribution at steady state was equal to the volume of the adult extracellular water compartment, and the rate of renal clearance of free drug corresponded to the normal glomerular filtration rate for adults. More than 70% of the administered dose was excreted as BAL9141 in the urine, and almost no prodrug was detected. After the infusion of 750 mg, the mean plasma BAL9141 concentrations exceeded the MIC at which 100% of MRSA isolates are inhibited (4 g/ml) for approximately 7 h, or 58% of a 12-h dosing interval. These results indicate that infusions of 750 mg twice a day should be adequate for the treatment of infections caused by MRSA.
Background: Increasing evidence shows that red wine consumption has cardioprotective effects. These effects have been attributed to the polyphenolic compounds in grapes. Objective: We studied the effects of red grape seed proanthocyanidins on the recovery of postischemic function in isolated rat hearts. Design: Two groups of rats were fed different doses of proanthocyanidin-rich extract for 3 wk and another group was untreated and served as controls. The animals were then anesthetized and the hearts were isolated and subjected to 30 min of ischemia followed by 2 h of reperfusion. Coronary effluents were collected during the third minute of reperfusion for measurement of oxygen free radicals by using electron spin resonance spectroscopy. Results: In rats treated with 50 and 100 mg grape seed proanthocyanidins/kg, the incidence of reperfusion-induced ventricular fibrillation was reduced from its control value of 92% to 42% and 25%, respectively (P < 0.05 for both). The incidence of ventricular tachycardia showed the same pattern. In rats treated with 100 mg proanthocyanidins/kg, the recovery of coronary flow, aortic flow, and developed pressure after 60 min of reperfusion was improved by 32% ± 8%, 98% ± 8%, and 37% ± 3%, respectively (P < 0.05 for all) compared with untreated control rats. Electron spin resonance studies indicated that proanthocyanidins significantly inhibited the formation of oxygen free radicals. In rats treated with 100 mg proanthocyanidins/kg, free radical intensity was reduced by 75% ± 7% (P < 0.05) compared with the control rats. Conclusion: Grape seed proanthocyanidins have cardioprotective effects against reperfusion-induced injury via their ability to reduce or remove, directly or indirectly, free radicals in myocardium that is reperfused after ischemia. 2002;75:894-9. Am J Clin Nutr
Soybean [Glycine max (L.) Merr.] seed composition and yield are a function of genetics (G), environment (E), and management (M) practices, but contribution of each factor to seed composition and yield are not well understood. The goal of this synthesis-analysis was to identify the main effects of G, E, and M factors on seed composition (protein and oil concentration) and yield. The entire dataset (13,574 data points) consisted of 21 studies conducted across the United States (US) between 2002 and 2017 with varying treatments and all reporting seed yield and composition. Environment (E), defined as site-year, was the dominant factor accounting for more than 70% of the variation for both seed composition and yield. Of the crop management factors: (i) delayed planting date decreased oil concentration by 0.007 to 0.06% per delayed week (R2∼0.70) and a 0.01 to 0.04 Mg ha-1 decline in seed yield per week, mainly in northern latitudes (40–45 N); (ii) crop rotation (corn-soybean) resulted in an overall positive impact for both seed composition and yield (1.60 Mg ha-1 positive yield difference relative to continuous soybean); and (iii) other management practices such as no-till, seed treatment, foliar nutrient application, and fungicide showed mixed results. Fertilizer N application in lower quantities (10–50 kg N ha-1) increased both oil and protein concentration, but seed yield was improved with rates above 100 kg N ha-1. At southern latitudes (30–35 N), trends of reduction in oil and increases in protein concentrations with later maturity groups (MG, from 3 to 7) was found. Continuing coordinated research is critical to advance our understanding of G × E × M interactions.
Administration of DiaPep277 seems safe and may have beneficial effects on C-peptide levels over time in some patients with T1D, but this finding was not accompanied by reduced HbA1c or insulin requirement. Studies with more patients and longer follow-up are needed to further study the effect of DiaPep277.
HighlightsPhenyl-/aminoalkylsilane-grafted silica gels were used as supports for CaLB.Adsorption onto mixed-function-grafted silica supports resulted in active CaLB.CaLB adsorption and glutardialdehyde cross-linking resulted in enhanced durability.The novel CaLB biocatalysts were used in kinetic resolutions of a secondary alcohol and an amine.The novel CaLBs were robust biocatalysts in continuous-flow biotransformations. AbstractAdsorption onto solid supports has proven to be an easy and effective way to improve the mechanical and catalytic properties of lipases. Covalent binding of lipases onto the support surface enhances the active lifetime of the immobilized biocatalysts. Our study indicates that mesoporous silica gels grafted with various functions are ideal supports for both adsorptive and covalent binding for lipase B from Candida antarctica (CaLB). Adsorption of CaLB on phenyl-functionalized silica gels improved in particular its specific activity, whereas adsorption on aminoalkyl-modified silica gels enabling covalent binding with the proper reagents resulted in only moderate specific activity. In addition, adsorption on silica gels modified by mixtures of phenyl-and aminoalkyl silanes significantly increased the productivity of CaLB. Furthermore, CaLB adsorbed onto a phenyl/aminoalkyl-modified surface and then treated with glutardialdehyde (GDA) as cross-linking agent provided a biocatalyst of enhanced durability. Adsorbed and cross-linked CaLB was resistant to detergent washing that would otherwise physically deactivate adsorbed CaLB preparations. The catalytic properties of our best immobilized CaLB variants, including temperaturedependent behavior were compared between 0 and 70 °C with those of two commercial CaLB biocatalysts in the continuous-flow kinetic resolutions of racemic 1-phenylethanol rac-1a and 1-phenylethanamine rac-1b.
Heme oxygenase-1 (HO-1)-dependent carbon monoxide (CO) production related to reperfusioninduced ventricular fibrillation (VF) was studied in HO-1 wild-type (+/+), heterozygous (+/−), and homozygous (−/−) isolated ischemic/reperfused mouse heart. In HO-1 homozygous myocardium, under aerobic conditions, HO-1 enzyme activity, HO-1 mRNA, and protein expression were not detected in comparison with aerobically perfused wild-type and heterozygous myocardium. In wild-type, HO-1 hetero-and homozygous hearts subjected to 20 min ischemia followed by 2 h of reperfusion, the expression of HO-1 mRNA, protein, and HO-1 enzyme activity was detected in various degrees. A reduction in the expression of HO-1 mRNA, protein, and enzyme activity in fibrillated wild-type and heterozygous myocardium was observed. In reperfused/nonfibrillated wild-type and heterozygous hearts, a reduction in HO-1 mRNA, protein expression, and HO-1 enzyme activity was not observed, indicating that changes in HO-1 mRNA, protein, and enzyme activity could be related to the development of VF. These changes were reflected in the HO-1-related endogenous CO production measured by gas chromatography. In HO-1 knockout ischemic/reperfused myocardium, all hearts showed VF, and no detection in HO-1 mRNA, protein, and enzyme activity was observed. Thus, interventions that are able to increase endogenous CO may prevent the development of VF.Key words: heme oxygenase-1 expression • ischemia/reperfusion • HO-1 knockout mouse hearts t has been proposed that most cases of sudden cardiac death may result from ischemia and/or reperfusion-induced ventricular fibrillation (VF; 1-3). Interest in the development and pharmacological control of reperfusion-induced VF has been stimulated by the realization that such arrhythmias may occur under a number of pathological and clinical circumstances, including the spontaneous relief of coronary artery spasm (4). There is considerable controversy over the mechanisms responsible for the induction of these arrhythmias, and a number of I different mechanisms have been suggested (5), but the two major factors proposed and generally accepted to explain reperfusion-induced injury and VF are 1) calcium overload and 2) free radical formation. Examples of oxidative stress-related diseases include reperfusion-induced injury occurring after tissue ischemia or stroke and inflammatory processes, such as arthritis (6). Heme oxygenase (HO) catalyzes the rate-limiting step in the oxidative degradation of heme to biliverdin and carbon monoxide (CO; ref 7). Three isozymes of HO have been identified and cloned; HO-1, an inducible form, HO-2, and HO-3 constitutive forms (8). Studies demonstrate that HO-1 is induced in response to various interventions causing oxidative stress, including ultraviolet irradiation, hypoxia, and ischemia (6,(9)(10)(11)(12).In previous studies, we observed a reduction in HO-1 mRNA expression, its protein, and enzyme activity in ischemic/reperfused fibrillated myocardium but not in nonfibrillated ischemic/reperfused hear...
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