Climate change and modernization drive structural realignments in European grain production.

Charting the long-term trends in European wheat and maize yields and harvested areas and the relation of yields to climatic and economic drivers, two profound spatial processes become apparent. One consequence of the relatively late modernization of Eastern Europe has been to shift the focus of grain production from West to East. The warming trend prevailing over the past decades in the summer and winter seasons has been accompanied by a South to North shift in the harvested areas. The combination of these two processes has meant that the north-eastern sector of the European grain chessboard has emerged as the main beneficiary. There, the relatively low sensitivity of cereals to climatic change plus high economic growth rates have been accompanied by the most dynamic increases in cereal yields on the continent. As a result, a modern version of the 3000 year-old grain distribution system of the Ancient World is being restored before our eyes. One noteworthy finding is that increasing January-March temperatures have had a significant positive impact on wheat yields from Northern to South-Eastern Europe, and this is, at least in part, compensating for the negative impact of summer warming.

Assessing collagen alterations in enzymatic degradation models of osteoarthritis via second harmonic generation microscopy.

INTRODUCTION: Structural changes in the collagen II architecture of osteoarthritis (OA) are poorly understood, which is a large shortcoming in the early diagnosis of this disease. Though degradation can be simulated by enzymes including trypsin and bacterial collagenase, the specific structural features of each digestion and their relationship to naturally occurring OA remain unclear. EXPERIMENTAL DESIGN: We used collagen sensitive/specific Second Harmonic Generation (SHG) microscopy in conjunction with optical scattering measurements to probe the resulting architecture changes in bovine knee cartilage upon trypsin and collagenase degradation. Image features extracted from SHG images were used to train a linear discriminant (LD) model capable of classifying enzymatic degradation, which was then applied to human cartilage with varied modified Mankin histological scores. RESULTS: The treatment of cartilage with these enzymes resulted in more disorganized collagen structure, where this effect was greatest with collagenase treatment. Using the LD model, we classified the control and degraded tissues in the three zones with >92% accuracy, showing that these enzymes have distinct activity on the collagen assembly. Application of the LD model to human cartilage indicated that collagenase effects were more representative of in vivo degeneration and were also consistent with damage beginning at the articular surface and progressing into deeper zones. CONCLUSIONS: SHG and optical scattering measurements successfully delineate trypsin and collagenase degradation and suggest that collagen alterations in human OA are better simulated by the latter mechanism. These results lay the groundwork for using high-resolution SHG and optical scattering as an earlier diagnostic tool than is currently available.

Quantitation of amino acids in plasma by high performance liquid chromatography: simultaneous deproteinization and derivatization with 9-fluorenylmethyloxycarbonyl chloride.

This paper, as a novelty to this field, presents the deproteinization and derivatization of plasma's free amino acids (PFAAs), simultaneously, in a single step, with the acetonitrile (ACN) containing 9-fluorenylmethyloxycarbonyl chloride (FMOC) reagent. Deproteinization and derivatization, were studied with 22 amino acids, applying photodiode array (DAD) and fluorescence (FL) detection, simultaneously. Model investigations have been carried out as a function of the FMOC concentration, reaction time and reaction conditions: with standard solutions, with human plasma samples in its initial condition and fortified with standard amino acids (excluding tryptophan because it co-elutes with the hydrolyzed FMOC). Reproducibilities of 22 amino acids, including both histidine and tyrosine derivatives, obtained under optimum derivatization conditions are presented (at 3.0 mM FMOC concentration, at pH 9; derivatization time - 20 min), and characterized with the relative standard deviation percentages of their responses (

Amino acid analysis by high-performance liquid chromatography after derivatization with 9-fluorenylmethyloxycarbonyl chloride Literature overview and further study.

A literature overview is given of HPLC methods currently in use to determine amino acids as their 9-fluorenylmethyloxycarbonyl (FMOC) derivatives. On the basis of the detailed literature overview an exhaustive derivatization study was performed with 22 amino acids, applying photodiode array (DAD) and fluorescence (FL) detection simultaneously, in order to clear up the controversial points of FMOC derivatization. Model investigations have been carried out as a function of the reaction time and reaction conditions, such as the molar concentration of the reagent, the molar ratios of the reactants, the pH and the solvent composition of the reaction medium. Special emphasis was put (i) on the evaluation of the blank values of the reagents, as a function of the composition and that of the pH of the reaction medium, (ii) on the unambiguous quantitation of all amino acids, including the less reactive aspartic and glutamic acids, as well as on the formation and transformation of histidine and tyrosine, existing partly, as single (N-FMOC-histidine, N-FMOC-tyrosine), partly as double labeled species (N,NH-FMOC-histidine, N,O-FMOC-tyrosine). Reproducibilities of 22 amino acids, including both histidine and tyrosine derivatives, obtained under optimum derivatization conditions are presented (at 0.5mM FMOC concentration corresponding to the molar ratios of [FMOC]/[amino acids](T)=5.5/1 (note: the superscript 'T' means the total of amino acids), with acetonitrile containing reagents, at pH 9, derivatization time=20 min), and characterized with the relative standard deviation percentages of their responses (

Advances in the o-phthalaldehyde derivatizations. Comeback to the o-phthalaldehyde-ethanethiol reagent.

The main aims of this work were (a) to present the characteristics and stability of the o-phthalaldehyde (OPA)-ethanethiol (ET) derivatives of 22 amino acids, including the believed-to-be less stable OPA derivatives providing glycine, gamma-aminobutyric acid, beta-alanine, histidine, ornithine, lysine and the C(1)-C(5) aliphatic amines; (b) to compare the stability properties of the most common amino acids and amines as OPA-ET-fluorenylmethyl chloroformate (FMOC) derivatives to the corresponding ones obtained from OPA reagents containing various (SH)-additives; (c) to show the molar responses of alanine and lysine depending on the OPA reagent's composition; as well as (d) to prove the practical utility of these basic researches, by the simultaneous HPLC separation of 22 amino acids and 15 amines as their OPA-ET-FMOC derivatives. Investigations have been carried out by varying the composition of the reagents, the molar ratios of reactants and the reaction time, applying diode array and fluorescence detections simultaneously. Average reproducibility of quantitations, characterized with the relative standard deviations (RSDs) based on the fluorescence intensities of derivatives, in the order of listing, proved to be 1.2-5.9% for amino acids and 1.1-8.7% for amines. The practical utility of the method is demonstrated by the analysis of the amino acid and amine contents of mouse tissues, with an average reproducibility of 3.5%.

Analysis of amino acids and biogenic amines in biological tissues as their o-phthalaldehyde/ethanethiol/fluorenylmethyl chloroformate derivatives by high-performance liquid chromatography. A deproteinization study.

The extraction of ornithine, lysine, putrescine, cadaverine, 1,7-diaminoheptane, spermidine and spermine from biological tissues was optimized for HPLC quantitation as their o-phthalaldehyde/ethanethiol/fluorenylmethyl chloroformate (OPA/ET/FMOC) derivatives. In applying perchloric acid deproteinization two approaches have been followed: (i) deproteinization with subsequent neutralization by potassium hydroxide and lyophilization, and (ii) deproteinization without neutralization and lyophilization. Neutralization and lyophilization resulted in the loss of free biogenic amines. HPLC analysis of ornithine (Orn), lysine (Lys), putrescine (Put), cadaverine (Cad), 1,7-diaminoheptane (Dah), spermidine (Spd) and spermine (Spm) content of biological tissues as their OPA/ET/FMOC derivatives was performed in the supernatant of perchloric acid-deproteinized samples (model solutions and tissues) with an average reproducibility of < or =2.6% relative standard deviation (RSD), including recovery of sample treatment and chromatography.