Identification of enterodiol as a masker for caffeine bitterness by using a pharmacophore model based on structural analogues of homoeriodictyol

Starting from previous structure-activity relationship studies of taste modifiers based on homoeriodictyol, dihydrochalcones, deoxybenzoins, and trans-3-hydroxyflavones as obvious analogues were investigated for their masking effect against caffeine. The most active compounds of the newly investigated taste modifiers were phloretin, the related dihydrochalcones 3-methoxy-2',4,4'-trihydroxydihydrochalcone and 2',4-dihydroxy-3-methoxydihydrochalcone, and the deoxybenzoin 2-(4-hydroxy-3-methoxyphenyl)-1-(4-hydroxyphenyl)ethanone. Starting with the whole set of compounds showing activity >22%, a (Q)SAR pharmacophore model for maskers of caffeine bitterness was calculated to explain the structural requirements. After docking of the pharmacophore into a structural model of the broadly tuned bitter receptor hTAS2R10 and docking of enterolactone and enterodiol as only very weakly related structures, it was possible to predict qualitatively their modulating activity. Enterodiol (25 mg L(-1)) reduced the bitterness of the 500 mg L(-1) caffeine solution by about 30%, whereas enterolactone showed no masking but a slight bitter-enhancing effect.     

Unusual systemic signs in a dog with sterile neutrophilic-macrophagic lymphadenitis and nodular panniculitis

A 7 mo old female English springer spaniel was presented with diarrhea, vomiting, apathy, and hyperthermia. Further examinations revealed generalized lymphadenomegaly consistent with sterile neutrophilic-macrophagic lymphadenitis and pulmonary involvement. Subcutaneous nodules developed one day after presentation. Histology was consistent with sterile idiopathic nodular panniculitis and vasculitis. No infectious organism was isolated. The dog responded to prednisolone, but relapsed during medication tapering. Cyclosporine had to be added to control the disease. No further relapse had occurred 98 wk after the first presentation. This is an unusual presentation of a systemic sterile neutrophilic-macrophagic lymphadenitis with nodular panniculitis and vasculitis associated with gastrointestinal and pulmonary signs.     

Pharmacokinetics and Effects of Alkalization During Oral and Intravenous Administration of Naproxen in Horses

The use of suitable therapeutic protocols is particularly important when extra-label drugs are used or when physiological parameters are modified, as in the case of the administration of alkaline substances to racehorses. The pharmacokinetics of naproxen (NAP), after both intravenous (iv) and oral administration of 10 mg/kg body weight (BW), was investigated in horses under normal metabolic conditions and in horses whose conditions were modified by the iv administration of 250 mg/kg BW of sodium bicarbonate (NaHCO₃). The hypothesis that blood and consequent urinary alkalization could modify NAP pharmacokinetics was evaluated. Drug quantification was performed on serum and urine using High Performance Liquid Chromatography (HPLC) with ultraviolet-visible detection. Results were also integrated with cycloxygenase (COX)-inhibition published data to suggest an appropriate schedule for NAP dosage in horses. After iv administration, NAP was rapidly distributed (t_1/2α: 0.71 ± 0.43 iv NaHCO₃ and 0.55 ± 0.62 hours No NaHCO₃), whereas its elimination was quite slow (t_1/2β: 6.74 ± 0.41 hours), particularly in iv NaHCO₃ animals (t_1/2β: 8.95 ± 1.37 hours). After oral treatments, NAP was more rapidly absorbed and elimination was slower in iv NaHCO₃ animals (t_1/2λ_z: 17.50 ± 6.66 vs. 7.17 ± 0.91 hours). The oral bioavailability of NAP was approximately 87% and 77% in No NaHCO₃ and iv NaHCO₃, respectively. Urinary excretion of the drug as a parent compound was low. The alkalization procedure did not anticipate the elimination of the acidic drug as expected, but it also influenced the absorption of the drug that was administered orally. The dosage scheme of 10 mg/kg BW iv or orally seems to be appropriate to produce an anti-inflammatory effect for 12 to 24 hours.     

A gamma‐ray spectrometry approach to field separation of illuviation‐type WRB reference soil groups in northern Thailand

According to the World Reference Base for Soil Resources (IUSS Working Group WRB, 2006), the differentiation of Acrisols and Alisols is based on the cation‐exchange capacity of clay, which cannot be directly determined in the field, but needs expensive and time‐consuming soil‐chemical analyses. This is an unsatisfactory situation for pedologists, who urgently require a rapid field method to distinguish illuviation‐type reference soil groups (Alisols, Acrisols, Luvisols, Lixisols). In this study, we tested the ability of gamma‐ray spectrometry to separate major WRB reference soil groups in the field. The underlying hypothesis is that Alisols and Acrisols are distinguished by their clay mineral composition, which should be reflected by geochemistry and consequently gamma‐ray radiation (i.e., K‐containing illite vs. K‐free kaolinite). Highly significant differences in their gamma‐ray spectrum for K, Th, and U were found for limestone and its soils. Especially the K and Th signatures allowed a clear separation of Acrisols and Alisols. In general, the surface radiation was sufficient to separate these soils. Best results were revealed considering parent rock and the whole soil profile. This means by using a portable radiometer and a pH meter, all illuviation‐type reference soil groups could be distinguished in this case. If applicable at other sites, this approach could enormously reduce expenditures for soil‐chemical analysis needed to assist soil classification.     

Boric acid as alternative reference substance for earthworm field tests

Purpose  

Boric acid was applied in an earthworm field test according to ISO 11268-3 as a possible alternative for the currently used reference substances that may no longer be available in the near future.     

Legume residue influence arbuscular mycorrhizal colonisation and P uptake by wheat

Legumes have been shown to increase growth and P uptake of the following cereal. This could, in part, be due to nutrients released by the decomposing legume residues. To investigate the effect of P added with legume residues on wheat growth, P uptake and arbuscular mycorrhizal (AM) colonisation, a number of experiments were conducted with different legume residues added to a soil with low P availability under conditions in which N was not limiting. Young and mature faba bean shoots (FYS, FMS) and mature chickpea shoots (CP) were added to soil at different rates (0.5–2%, w/w) with the P concentration being the greatest in the young faba bean shoots and least in the mature chickpea residues. Other treatments included addition of inorganic P at different rates (0–80 mg P kg⁻¹). Available P, growth and P uptake and AM colonisation of wheat were measured after 6 weeks. As expected, inorganic P addition increased growth and P uptake but decreased AM colonisation. The effect of the residues was more complex. AM colonisation was not correlated with available P in the soil amended with residues, whereas there was significant negative correlation between available P and AM colonisation in the treatments with inorganic P. Addition of FYS increased wheat shoot growth and P uptake and decreased AM colonisation. However, FMS and CP addition not only decreased wheat growth and P uptake but also AM colonisation despite low soil P availability. It is concluded that addition of some legume residues can improve the growth of subsequent cereals, but others have a negative effect on wheat growth and AM colonisation which cannot be explained solely by soil P availability.     

Effect of mono- and divalent cations on sorption of water-extractable organic carbon and microbial activity

Biology and Fertility of Soils - Sorption is an important process for retention of organic carbon (C) in soils. The effect of Na+ and Ca2+ on sorption of organic C has been studied in salt-affected...     

Previous water content influences the response of soil respiration to changes in water content in non-saline and saline soils

Three incubation experiments were carried out with a non-saline soil (electrical conductivity in a saturation paste (ECe) 1 dS m^?1) to which NaCl was added to achieve ECe 10 and 30 dS m^?1; pea straw was added at 20 g kg^?1 as a nutrient source. Experiment 1 showed that cumulative respiration was highest in soil EC 1 and lowest in soil EC 30. The optimal water content for respiration was 60–70 % of WHC in all soils. There were two periods (days 1–7 and days 8–17) in Experiment 2. In the treatments with the same water content in both periods [optimal (O-O) and medium (M-M)], respiration rates decreased over time and were lower in M-M than in O-O. Cumulative respiration at medium water content did not differ between slow (L-SM) or rapid rewetting (L-RM) from low to medium water content. There were two periods in Experiment 3 with the water content in the first period 50, 40 or 30 % of WHC adjusted from 60 % during pre-incubation either slowly or rapidly. The water content in the second period was maintained or adjusted slowly to 30–60 %. Cumulative respiration differed between water contents but was not consistently different between rapid and slow drying in the first period. We conclude that the response of microbial activity to a certain water content is influenced by the previous water content whereas the speed at which the water content is adjusted had little effect on respiration at target water content.     

Quantitative resistance to Botrytis cinerea from Solanum neorickii

Tomato (Solanum lycopersicum) is susceptible to gray mold (Botrytis cinerea). Quantitative resistance to B. cinerea was previously identified in a wild relative, S. neorickii G1.1601. The 122 F₃ families derived from a cross between the susceptible S. lycopersicum cv. Moneymaker and the partially resistant S. neorickii G1.1601 were tested for susceptibility to B. cinerea using a stem bioassay. Three putative quantitative trait loci (pQTL) were detected: pQTL3 and pQTL9 reducing lesion growth (LG) and pQTL4 reducing disease incidence (DI). For each pQTL, a putative homologous locus was identified recently in another wild tomato relative, S. habrochaites LYC4. pQTL3 was confirmed by assessing disease resistance in BC₃S₁ and BC₃S₂ progenies of S. neorickii G1.1601. pQTL4 was not statistically confirmed but the presence of the S. neorickii resistance allele reduced DI in all three tested populations. The reduction in LG of pQTL9 was not confirmed but rather, this locus conferred a reduced DI, similar to observations in the QTL study using S. habrochaites. The results are discussed in relation to other disease resistance loci identified in studies with other wild tomato relatives.