A procedure to infect lettuce seedlings with oospores of Bremia lactucae

Samenvatting Oösporen vanBremia lactucae kunnen worden verkregen door bladschijfjes van sla te inoculeren met een gemengde conidiënsuspensie van twee fysio's van de schimmel, die de twee compatibiliteitstypen (B₁ en B₂) vertegenwoordigen. Wanneer het bladweefsel geheel vergaan is, worden de schijfjes met oösporen samen met het onderliggende filtreerpapier op een dunne laag grond in een glazen schaaltje gebracht. Hierop worden vijf zaden van een vatbaar slaras te kiemen gelegd. Zaailingen die worden aangetast vertonen na drie tot vijf weken sporulatie op de cotylen. De conidiën worden op een toetssortiment van slarassen gespoten om het aantastingspatroon van het isolaat te bepalen. De eerste resultaten toonden aan dat de nakomelingen van een kruising gewoonlijk een beperkter aantastingspatroon hebben dan de ouders.     

Improved bioavailability of dietary phenolic acids in whole grain barley and oat groat following fermentation with probiotic Lactobacillus acidophilus , Lactobacillus johnsonii , and Lactobacillus reuteri

The aim of this study was to improve the bioavailability of the dietary phenolic acids in flours from whole grain barley and oat groat following fermentation with lactic acid bacteria (LAB) exhibiting high feruloyl esterase activity (FAE). The highest increase of free phenolic acids was observed after fermentation with three probiotic strains, Lactobacillus johnsonii LA1, Lactobacillus reuteri SD2112, and Lactobacillus acidophilus LA-5, with maximum increases from 2.55 to 69.91 μg g(-1) DM and from 4.13 to 109.42 μg g(-1) DM in whole grain barley and oat groat, respectively. Interestingly, higher amounts of bound phenolic acids were detected after both water treatment and LAB fermentation in whole grain barley, indicating higher bioaccessibility, whereas some decrease was detected in oat groat. To conclude, cereal fermentation with specific probiotic strains can lead to significant increase of free phenolic acids, thereby improving their bioavailability.     

Influence of Hatchery Protocols on Mitochondrial DNA Variation in Japanese Flounder Juveniles

The Japanese flounder Paralichthys olivaceus is a commercially important fish that is stocked extensively from hatchery rearing programs in Japan. To examine the genetic variability of hatchery-raised juveniles of the Japanese flounder that are used for stocking into natural waters, we analyzed a portion of the mitochondrial genome. The mtDNA region extending from the 3'half of the cytochrome b gene to the central domain of the control region was PCR amplified and analyzed using 11 restriction endonucleases. We identified 34 polymorphic cleavage sites out of a total of 61 sites, which resulted in 67 different haplotypes in a total of 265 offspring, examined from eight hatchery stocks. Haplotype diversity of offspring at each of the eight hatcheries ranged from 0.49 ± 0.09 (SE) to 0.94 ± 0.03 (SE). Also, we observed 40 polymorphic sites out of a total of 59 sites, which resulted in a total of 50 haplotypes in 60 wild flounder. Haplotype diversity of the wild population was 0.98 ± 0.01 (SE). The use of subcultured fishes as broodstock appears to be one of the most important causes of reduced genetic diversity in hatchery-raised flounder juvenile. Our results suggest that the use of wild fish for broodstock is an effective way to maintain genetic variability in Japanese flounder offspring.     

Curing kinetics study of melamine–urea–formaldehyde resin/liquefied wood

The objective of this research was to investigate the effect of liquefied wood (LW) on the cure kinetics and network properties of melamine–urea–formaldehyde (MUF) resins by differential scanning calorimetry. The MUF/LW compounds exhibited two distinct cross-linking processes. It can be assumed that there did not appear to be a coreaction of the MUF with the LW. The overall apparent activation energies (E _a) of the curing reactions were calculated using the Kissinger equation. An nth-order kinetic model was used to describe the cross-linking of MUF/LW compounds, of various compositions, cured at different heating rates. The E _a values for the cross-linking process of the MUF/LW compounds predominantly tended to be approximately 80 and 71 kJ mol^?1 for MUF and LW, respectively. The apparent reaction orders of the MUF cross-linking process of the MUF/LW compounds were in the range 1–2, whereas the n values of the LW were approximately unity or less, which hints to there being a more complex mechanism of this process.     

Effect of ephedrine and phenylephrine on cardiopulmonary parameters in horses undergoing elective surgery

ObjectiveTo assess the cardiopulmonary effects of ephedrine and phenylephrine for management of isoflurane‐induced hypotension in horses.Study designProspective randomized clinical study.AnimalsFourteen isoflurane‐anesthetized horses undergoing digital palmar neurectomy.MethodsEphedrine (EPH group; 0.02 mg kg^?1 minute^?1; n = 7) or phenylephrine (PHE group; 0.002 mg kg^?1 minute^?1; n = 7) was administered to all horses when mean arterial pressure (MAP) was <60 mmHg. The infusions were ended when the target MAP was achieved, corresponding to a 50% increase over the pre‐infusion MAP (baseline). The horses were instrumented with an arterial catheter to measure blood pressure and allow the collection of blood for pH and blood‐gas analysis and a Swan‐Ganz catheter for measurement of cardiac output using thermodilution. Cardiopulmonary parameters were recorded at baseline and at 5, 30, 60 and 90 minutes after achieving the target MAP.ResultsIn both groups, the MAP and systemic vascular resistance (SVR) increased significantly at 5, 30, 60 and 90 minutes post infusion compared to baseline (p < 0.05). The EPH group had a significant increase in cardiac index (CI) and systemic oxygen delivery index at 5, 30, 60 and 90 minutes post infusion compared to baseline (p < 0.05) and compared to the PHE group (p < 0.05). The PHE group had significantly higher SVR and no decrease in oxygen extraction compared with the EPH group at 30, 60 and 90 minutes post infusion (p < 0.05). No significant differences in ventilatory parameters were observed between groups after the infusion.ConclusionsEphedrine increased the MAP by increasing CI and SVR. Phenylephrine increased MAP by increasing SVR but cardiac index decreased. Ephedrine resulted in better tissue oxygenation than phenylephrine.Clinical relevanceEphedrine would be preferable to phenylephrine to treat isoflurane‐induced hypotension in horses since it increases blood flow and pressure.     

Inheritance of virulence in Bremia lactucae to match several resistance factors in lettuce

A 1∶1 mixture of spores of the physiologic races NL5 and NL6 ofBremia lactucae was sprayed on leaf discs of the lettuce cultivar Olof. The resulting oospores were allowed to germinate on seedlings after a two-month ripening period. Monospore lines of 49 of the 79 recovered isolates were tested on cotyledons and leaf discs of a differential series for virulence to 11 resistance factors. All monospore lines were also tested for the mating type factor. A backcross of a progeny line, line H, with NL5 was made and 41 isolates tested on the differential series. Results indicated complex inheritance based on more than one locus each for virulence to R2 and R11. Vilulence to match the resistance factor R4 seems to be based on a dominant factor or on a combination of a dominant and a recessive factor. Virulence to factors R5, R8 and R10 are recessive and possibly interchangeable. Inheritance of virulence to factors R3, R6 and R9 must be studied further before definite conclusions can be drawn. Virulence to R7 resulted in many incomplete reactions, but all showed significantly less sporulation than the virulent parent. Variations in necrosis in intermediate reactions indicate the presence of minor genes affecting these symptoms. Many of the avirulent loci in the parent lines proved to be heterozygous. Mating type segregation fits a 1∶1 ratio, indicating that this factor is controlled by a single gene. Selfing, mutation and somatic crossing-over can affect the ratios of recovered progeny and so our conclusions concerning the inheritance of virulence.