Off-label antiobesity treatment in patients without diabetes with GLP-1 agonists in clinical practice.

The aim of the work was to investigate whether continuation of treatment, side effects, and effect on weight loss of GLP-1 agonists in obese patients without diabetes are equally promising in daily clinical-practice-settings compared to controlled clinical trials. Obese patients without diabetes of our interdisciplinary obesity centre were treated off-label with GLP-1-agonists for different time periods. Application was started with low-dose and increased if side effects were tolerable. Monthly costs were € 125 for daily applications of 1.2 mg liraglutide or 10 µg exenatide twice daily. Data were obtained by telephone interviews about baseline characteristics, weight loss, sensation of satiation, duration of therapy, side effects, and reasons for discontinuation. Of 43 included cases (5 males, mean age 43±11 years, mean weight 107±24 kg, mean excess weight 35±21 kg) 7 were treated with exenatide and 36 with liraglutide. Excess weight loss in linear regression models was 6.7% per month (p <0.05) under control of age, sex, initial weight, and type of GLP-1 analogue treatment and did not significantly differ between liraglutide and exenatide. Overall, 58% of patients reported side effects mostly concerning the gastrointestinal tract. Surprisingly no patient reported vomiting. One patient developed a severe pancreatitis. At time of telephone interview only 30.2% were continuing treatment. Mean treatment duration was 2.98±2.71 months. Common reasons for discontinuation of treatment were no/little effect on weight loss (27.9%), intolerable side effects (20.9%), or financial reasons (14%). GLP-1 agonist treatment in obese patients without diabetes also correlates with significant weight loss in clinical practice. However, side effects and discontinuation of treatment are common. Therefore, long-term effect on weight loss might not be as promising as suggested by data from clinical trials.

Hyponatremia after trans-sphenoidal surgery.

Fluid and electrolyte imbalances are the most frequent complications following pituitary surgery. Among the several patterns of occurrence, hyponatremia can occur in an isolated fashion or as part of a bi- or triphasic pattern. The frequency of hyponatremia after trans-sphenoidal surgery is between 2% and 25%, according to the literature. However, these numbers are probably underestimating the real prevalence, since mild hyponatremia does not lead to symptoms and measurement of sodium level. No association has been described between entity of the pituitary tumor or tumor size and hyponatremia. Therefore no predictors exist to determine patients with a higher risk for electrolyte imbalances after surgery. However, since delayed hyponatremia occurs mainly around the 8-10th day after surgery, routine measurement of sodium should be recommended on the day of hospital dismission. In case of a symptomatic hyponatremia, insufficiency of the corticotrophe pituitary function as the leading differential diagnosis needs to be ruled out. If the patient is euvoleme, pretest probability of syndrome of inadequate antidiuretic hormone production (SIADH) is very high and therapy may be started according to this. In case of SIADH, therapeutic options include fluid restriction or vaptane therapy. Only in severe cases infusion of hypertonic saline is appropriate. Usually SIADH following pituitary surgery is a self-limiting condition and will cease within 2-5 days.

Effect of feeding level on ileal and total tract digestibility of nutrients and energy from soybean meal-based diets for piglets.

A total of 36 piglets with an initial body weight (BW) of 5.6 ± 0.7 kg, fitted with simple T-cannulas at the distal ileum, were used to evaluate the effect of three graded feeding levels (50, 75 or 100 g/kg BW(0.75) day) on apparent ileal digestibility (AID) and total tract digestibility (ATTD) of dry matter (DM), nitrogen (N) and energy, and on ATTD of organic matter (OM), ether extracts (EE), neutral detergent fibre (NDF), acid detergent fibre (ADF) and digestible (DE), metabolisable (ME) and net energy (NE) content in soybean meal (SBM)-casein-cornstarch-based diets. The AID of DM, N and energy and ATTD of NDF, ADF and EE in the diets were not affected (p > 0.05) by the feed intake (FI) level. There was a small decrease in ATTD of DM, N (CP), OM, ash and energy, and in DE, ME and NE content in the diets (p < 0.05) with increasing FI level. The net disappearance in the large intestine (in % of ileal recovery) decreased for DM, N and energy (p < 0.05) with increasing FI level. The design of the study allowed for estimating ileal endogenous loss of N and total tract endogenous loss of ash, N and EE, for estimating corresponding true ileal and total tract digestibility values, and for estimating urinary endogenous N loss. High variability in estimates of ileal endogenous N loss and total tract endogenous losses of N, EE and ash reflects great variation in individual endogenous losses between animals. Estimation of true total tract digestibility of N, EE and ash by regression analysis was affected by their decrease in ATTD with increasing FI level, as estimates for true digestibility were lower compared to their apparent values. The present results suggest that FI level can affect both apparent and true total tract nutrient digestibility in piglets.

Specific collaborative group intervention for patients with medically unexplained symptoms in general practice: a cluster randomized controlled trial.

BACKGROUND: Patients with medically unexplained symptoms (MUS) are frequent in primary care and substantially impaired in their quality of life (QoL). Specific training of general practitioners (GPs) alone did not demonstrate sustained improvement at later follow-up in current reviews. We evaluated a collaborative group intervention. METHODS: We conducted a cluster randomized controlled trial. Thirty-five GPs recruited 304 MUS patients (intervention group: 170; control group: 134). All GPs were trained in diagnosis and management of MUS (control condition). Eighteen randomly selected intervention GPs participated in training for a specific collaborative group intervention. They conducted 10 weekly group sessions and 2 booster meetings in their practices, together with a psychosomatic specialist. Six and 12 months after baseline, QoL was assessed with the Short-Form 36. The primary outcome was the physical composite score (PCS), and the secondary outcome was the mental composite score (MCS). RESULTS: At 12 months, intention-to-treat analyses showed a significant between-group effect for the MCS (p = 0.023) but not for the PCS (p = 0.674). This effect was preceded by a significant reduction of somatic symptom severity (15-item somatic symptom severity scale of the Patient Health Questionnaire, PHQ-15) at 6 months (p = 0.008) that lacked significance at 12 months (p = 0.078). As additional between-group effects at 12 months, per-protocol analyses showed less health anxiety (Whiteley-7; p = 0.038) and less psychosocial distress (PHQ; p = 0.024); GP visits were significantly (p = 0.042) reduced in the intervention group. CONCLUSIONS: Compared to pure GP training, collaborative group intervention achieved a progressive, clinically meaningful improvement in mental but not physical QoL. It could bridge gaps between general practice and mental health care.

A novel mechanism for target gene-specific SWI/SNF recruitment via the Snf2p N-terminus.

Chromatin-remodeling complexes regulate the expression of genes in all eukaryotic genomes. The SWI/SNF complex of Saccharomyces cerevisiae is recruited to its target promoters via interactions with selected transcription factors. Here, we show that the N-terminus of Snf2p, the chromatin remodeling core unit of the SWI/SNF complex, is essential for the expression of VHT1, the gene of the plasma membrane H(+)/biotin symporter, and of BIO5, the gene of a 7-keto-8-aminopelargonic acid transporter, biotin biosynthetic precursor. chromatin immunoprecipitation (ChIP) analyses demonstrate that Vhr1p, the transcriptional regulator of VHT1 and BIO5 expression, is responsible for the targeting of Snf2p to the VHT1 promoter at low biotin. We identified an Snf2p mutant, Snf2p-R(15)C, that specifically abolishes the induction of VHT1 and BIO5 but not of other Snf2p-regulated genes, such as GAL1, SUC2 or INO1. We present a novel mechanism of target gene-specific SWI/SNF recruitment via Vhr1p and a conserved N-terminal Snf2p domain.

Brief psychodynamic interpersonal psychotherapy for patients with multisomatoform disorder: randomised controlled trial.

BACKGROUND: Multisomatoform disorder is characterised by severe and disabling bodily symptoms, and pain is one of the most common and impairing of these. Furthermore, these bodily symptoms cannot be explained by an underlying organic disorder. Patients with multisomatoform disorder are commonly found at all levels of healthcare and are typically difficult to treat for physicians as well as for mental health specialists. AIMS: To test whether brief psychodynamic interpersonal therapy (PIT) effectively improves the physical quality of life in patients who have had multisomatoform disorder for at least 2 years. METHOD: We recruited 211 patients (from six German academic outpatient centres) who met the criteria for multisomatoform disorder for a randomised, controlled, 12-week, parallelgroup trial from 1 July 2006 to 1 January 2009 (International Standard Randomised Controlled Trial Number ISRCTN23215121). We randomly assigned the patients to receive either 12 weekly sessions of PIT (n = 107) or three sessions of enhanced medical care (EMC, n = 104). The physical component summary of the Short Form Health Survey (SF-36) was the pre-specified primary outcome at a 9-month follow-up. RESULTS: Psychodynamic interpersonal therapy improved patients' physical quality of life at follow-up better than EMC (mean improvement in SF-36 score: PIT 5.3, EMC 2.2), with a small to medium between-group effect size (d = 0.42, 95% CI 0.15-0.69, P = 0.001). We also observed a significant improvement in somatisation but not in depression, health anxiety or healthcare utilisation. CONCLUSIONS: This trial documents the long-term efficacy of brief PIT for improving the physical quality of life in patients with multiple, difficult-to-treat, medically unexplained symptoms.

Short-term effect of dietary yeast nucleotide supplementation on small intestinal enzyme activities, bacterial populations and metabolites and ileal nutrient digestibilities in newly weaned pigs.

In previous studies, dietary nucleotides have been shown to improve performance in single-stomached animals by promoting the renewal of small intestine epithelial cells and by influencing the activity and composition of the microbial community in the digestive tract. The present experiment was carried out with 12 barrows weaned at the age of 18 days and fitted with a simple T-cannula at the distal ileum. To determine short-term effects of dietary yeast nucleotides, the piglets received a grain-soybean meal-based basal diet with or without supplementation of 1 g/kg of a dried yeast product containing free nucleotides. Dietary supplementation with yeast did not affect bacterial numbers in the ileum as well as ileal concentrations of individual short-chain fatty acids (SCFA), total SCFA and total lactic acid (p > 0.05). Moreover, there was no effect of supplemental yeast nucleotides on ileal α-amylase, leucine amino peptidase, maltase and lactase activities (p > 0.05), as well as on ileal dry matter, crude protein and crude fibre digestibilities (p > 0.05). In conclusion, short-term supplementation with dietary yeast nucleotides did not affect microbial metabolite concentrations, bacterial numbers and enzyme activities in the ileal digesta as well as ileal nutrient digestibilities of newly weaned pigs.

Functional relaxation and guided imagery as complementary therapy in asthma: a randomized controlled clinical trial.

BACKGROUND: Asthma is a frequently disabling and almost invariably distressing disease that has a high overall prevalence. Although relaxation techniques and hypnotherapeutic interventions have proven their effectiveness in numerous trials, relaxation therapies are still not recommended in treatment guidelines due to a lack of methodological quality in many of the trials. Therefore, this study aims to investigate the efficacy of the brief relaxation technique of functional relaxation (FR) and guided imagery (GI) in adult asthmatics in a randomized controlled trial. METHODS: 64 patients with extrinsic bronchial asthma were treated over a 4-week period and assessed at baseline, after treatment and after 4 months, for follow-up. 16 patients completed FR, 14 GI, 15 both FR and GI (FR/GI) and 13 received a placebo relaxation technique as the control intervention (CI). The forced expiratory volume in the first second (FEV(1)) as well as the specific airway resistance (sR(aw)) were employed as primary outcome measures. RESULTS: Participation in FR, GI and FR/GI led to increases in FEV(1) (% predicted) of 7.6 +/- 13.2, 3.3 +/- 9.8, and 8.3 +/- 21.0, respectively, as compared to -1.8 +/- 11.1 in the CI group at the end of the therapy. After follow-up, the increases in FEV(1) were 6.9 +/- 10.3 in the FR group, 4.4 +/- 7.3 in the GI and 4.5 +/- 8.1 in the FR/GI, compared to -2.8 +/- 9.2 in the CI. Improvements in sR(aw) (% predicted) were in keeping with the changes in FEV(1) in all groups. CONCLUSIONS: Our study confirms a positive effect of FR on respiratory parameters and suggests a clinically relevant long-term benefit from FR as a nonpharmacological and complementary therapy treatment option.

Meta-analysis of the relative efficiency of methionine-hydroxy-analogue-free-acid compared with DL-methionine in broilers using nonlinear mixed models.

The purpose of this paper was to perform a meta-analysis to compare the biological efficiency of DL-methionine with methionine-hydroxy-analogue-free-acid in broiler chickens. A database was developed which contained dose-response studies of these 2 methionine sources. Criteria for entry into the database were defined before the meta-analysis was initiated. Data from 46 dose-response experiments, extracted from a total of 27 peer-reviewed papers, were used for the analysis with the Statistical Analysis System. Initially, the NLIN procedure was applied to fit an exponential model of the form y = alpha + beta*[1 - exp (-Gamma*dose)] + e. Thereafter, meta-analysis was conducted by means of nonlinear mixed models, which were fitted by a full maximum likelihood method as implemented in the NLMIXED procedure. The nonlinear model used for the analysis allowed for separate plateaus or different efficiencies of the methionine sources. Mixed modeling was applied to account for heterogeneity among the studies in all regression parameters for both sources of methionine via random effects. Statistical hypotheses were tested by the asymptotic Wald test. In addition, potential co-variables were tested for inclusion as linear regressors for the nonlinear model parameters. In conclusion, the null hypothesis of equal plateaus of the 2 methionine sources was not rejected. The analyses of the response variables average daily gain (ADG) and gain to feed ratio (GF) showed a highly significant difference between the tested methionine sources. The covariate age at start of experiment significantly affected the intercept term alpha for the response variables ADG and GF, respectively. The meta-analysis showed that biological efficiencies of DL-methionine-hydroxy-analogue-free-acid were 81 and 79% of the values for DL-methionine, on an equimolar basis, for ADG and GF, respectively.

Phloem Loading by the PmSUC2 Sucrose Carrier from Plantago major Occurs into Companion Cells.

High levels of mRNA for the sucrose-H+ symporter PmSUC2 have been found in the vascular bundles of petioles from Plantago major. The possible role of PmSUC2 in phloem loading was studied with antiserum raised against the recombinant PmSUC2 protein. This antiserum labeled a single 35-kD protein band in detergent extracts of P. major vascular bundles. It showed no cross-reaction with the P. major sucrose carrier PmSUC1, which was tested with detergent extracts from plasma membranes of transgenic yeast strains containing either the P. major sucrose transporter PmSUC1 or PmSUC2. The antiserum was used to determine the site of PmSUC2 expression in leaves, petioles, and roots of P. major. In cross-sections and longitudinal sections, the PmSUC2 protein was found in only one single cell type. These cells were identified as companion cells because they are nucleated, contain a dense cytoplasm, and are always adjacent to a sieve element. The labeled cells had the same longitudinal extension as did their sister sieve elements and always ended next to the sieve plates, which were characterized by specific staining. PmSUC2 mRNA and PmSUC2 protein were also detected in P. major roots. The function of PmSUC2 in the different organs and its role in phloem loading are discussed.

Differential regulation of a hydroxyproline-rich glycoprotein gene family in wounded and infected plants.

We have characterized three different transcripts induced by fungal elicitor, wounding, or infection which encode apoproteins of cell wall hydroxyproline-rich glycoproteins involved in plant defense against infection. The proteins encoded by two of these transcripts contain a proline-rich domain involving tandem repetition of the 16-amino-acid unit Tyr3-Lys-Ser-Pro4-Ser-Pro-Ser-Pro4. The third transcript encodes a protein with a proline-rich domain involving a variant of this 16-mer canonical repeat: Tyr3-His-Ser-Pro4-Lys-His-Ser-Pro4. Each transcript is encoded by a separate gene present at single or low copy number in the haploid genome. These transcripts exhibit markedly different patterns of accumulation in different stress conditions, indicating the operation of several distinct intercellular stress signal systems in higher plants.

Immunolocalization of the PmSUC1 sucrose transporter in Plantago major flowers and reporter-gene analyses of the PmSUC1 promoter suggest a role in sucrose release from the inner integument.

This paper presents a detailed analysis of the PmSUC1 gene from plantago major, of its promoter activity in Arabidopsis, and of the tissue specific localization of the encoded protein in Plantago. PmSUC1 promoter activity was detected in the innermost layer of the inner integument (the endothel) of Arabidopsis plants expressing the gene of the green fluorescent protein (GFP) under the control of the PmSUC1 promoter. This promoter activity was confirmed with a PmSUC1-specific antiserum that identified the PmSUC1 protein in the endothel of Plantago and of Arabidopsis plants expressing the PmSUC1 gene under the control of its own promoter. PmSUC1 promoter activity and PmSUC1 protein were also detected in pollen grains during maturation inside the anthers and in pollen tubes during and after germination. These results demonstrate that PmSUC1 is involved in sucrose partitioning to the young embryo and to the developing pollen and growing pollen tube. In the innermost cell layer of the inner integument, a tissue that delivers nutrients to the endosperm and the embryo, PmSUC1 may catalyze the release of sucrose into the apoplast.

Functional characterisation and cell specificity of BvSUT1, the transporter that loads sucrose into the phloem of sugar beet (Beta vulgaris L.) source leaves.

Sugar beet (Beta vulgaris L.) is one of the most important sugar-producing plants worldwide and provides about one third of the sugar consumed by humans. Here we report on molecular characterisation of the BvSUT1 gene and on the functional characterisation of the encoded transporter. In contrast to the recently identified tonoplast-localised sucrose transporter BvTST2.1 from sugar beet taproots, which evolved within the monosaccharide transporter (MST) superfamily, BvSUT1 represents a classical sucrose transporter and is a typical member of the disaccharide transporter (DST) superfamily. Transgenic Arabidopsis plants expressing the ß-GLUCURONIDASE (GUS) reporter gene under control of the BvSUT1-promoter showed GUS histochemical staining of their phloem; an anti-BvSUT1-antiserum identified the BvSUT1 transporter specifically in phloem companion cells. After expression of BvSUT1 cDNA in bakers' yeasts (Saccharomyces cerevisiae) uptake characteristics of the BvSUT1 protein were studied. Moreover, the sugar beet transporter was characterised as a proton-coupled sucrose symporter in Xenopus laevis oocytes. Our findings indicate that BvSUT1 is the sucrose transporter that is responsible for loading of sucrose into the phloem of sugar beet source leaves delivering sucrose to the storage tissue in sugar beet taproot sinks.

Sugar transporters in higher plants--a diversity of roles and complex regulation.

Sugar-transport proteins play a crucial role in the cell-to-cell and long-distance distribution of sugars throughout the plant. In the past decade, genes encoding sugar transporters (or carriers) have been identified, functionally expressed in heterologous systems, and studied with respect to their spatial and temporal expression. Higher plants possess two distinct families of sugar carriers: the disaccharide transporters that primarily catalyse sucrose transport and the monosaccharide transporters that mediate the transport of a variable range of monosaccharides. The tissue and cellular expression pattern of the respective genes indicates their specific and sometimes unique physiological tasks. Some play a purely nutritional role and supply sugars to cells for growth and development, whereas others are involved in generating osmotic gradients required to drive mass flow or movement. Intriguingly, some carriers might be involved in signalling. Various levels of control regulate these sugar transporters during plant development and when the normal environment is perturbed. This article focuses on members of the monosaccharide transporter and disaccharide transporter families, providing details about their structure, function and regulation. The tissue and cellular distribution of these sugar transporters suggests that they have interesting physiological roles.

Chemical composition and standardized ileal amino acid digestibility of eight genotypes of rye fed to growing pigs.

A study with growing pigs was conducted to determine the chemical composition, physical characteristics, and standardized ileal digestibility (SID) of CP and AA of 8 rye genotypes that have recently been added to the German Descriptive Variety List. Eight barrows with an initial BW of 24 ± 2 kg were fitted with T-cannulas at the distal ileum and allotted to an 8 × 8 Latin square design with 8 periods of 6 d each and 8 pigs receiving 8 different diets. The N-free method was used to determine the basal ileal endogenous CP and AA losses. The 8 assay diets contained 1 of 8 rye genotypes (Guttino, Palazzo, Visello, Bellami, Dukato, Conduct, Helltop, and Dankowski Diament) as the sole source of CP and AA. The rye genotypes were grown under identical environmental conditions on the same site. Among the 8 rye genotypes, contents of CP ranged from 9.5 to 11.2% (as-fed basis) and contents of total nonstarch polysaccharides (NSP) ranged from 10.7 to 12.9% (as-fed basis). Arabinoxylan (AX) constituted the major NSP fraction, with values ranging from 6.5 to 7.6% (as-fed basis). Among the 8 rye genotypes, starch contents ranged from 55.7 to 57.5% (as-fed basis). The SID of CP in the 8 rye genotypes ranged from 70 to 74%. The SID of Cys in genotypes Visello, Bellami, Dukato, and Dankowski Diament was lower ( < 0.05) when compared with Palazzo, Conduct, and Helltop. For all other AA, SID in the 8 rye genotypes did not differ. The standardized ileal digestible content (cSID) of CP was greatest ( < 0.001) in genotype Dankowski Diament (8.1%, as-fed basis) and lowest ( < 0.001) in genotype Guttino (6.9%, as-fed basis). Genotype Guttino had the lowest ( < 0.05) cSID of AA among all rye genotypes, except for Trp, Gly, and Pro. For Thr, Ala, and Gly, there were no differences in cSID among the 8 rye genotypes. For CP and most AA, cSID decreased as contents of total and insoluble ß-glucan ( < 0.05), total AX, and soluble NSP increased ( < 0.05). The results of the present study provide a comprehensive database on chemical composition, physical characteristics, and SID of CP and AA of 8 rye genotypes grown under same conditions. However, as present SID values of these recently introduced genotypes are lower compared to values in feed tables, adjustments are possibly required to minimize the risk of overestimating the actual protein value of rye for pigs.

Standardized ileal digestibility of amino acids in eight genotypes of barley fed to growing pigs.

To determine chemical composition, physical characteristics and standardized ileal digestibility (SID) of CP and amino acids (AA) in eight current hulled barley genotypes, an experiment with growing pigs has been conducted. These genotypes included Yool, Campanile, Lomerit, Travira, Anisette, Canberra, Metaxa and Fridericus. Growing barrows with an average initial BW of 30±2 kg were surgically fitted with simple T-cannulas at the distal ileum, and allotted to an 8×9 Youden square design with eight periods of 6 days each and nine pigs. Barley was the sole dietary source of CP and AA. On average, the eight genotypes contained on as-fed basis 10.7% CP, 15.2% total non-starch polysaccharides (NSP), 17.1% NDF and 4.1% ß-glucan, and had a mean test weight (TW) of 72.2 kg/hl. The SID of CP in the barley genotypes varied from 69% to 74%, and was greater (P<0.01) for genotypes Travira, Anisette and Metaxa compared to Yool and Campanile. Standardized ileal digestibility of Lys, Met and Trp (P<0.05) but not of Thr differed between genotypes. Moreover, barley genotypes differed in their standardized ileal digestible content (cSID) of CP and AA. Furthermore, SID and cSID of CP and most AA linearly decreased (P<0.05) with increasing NDF and total sugar content. Standardized ileal digestibility of CP and some AA and cSID of CP and most AA decreased linearly with increasing TW (P<0.05). Additionally, SID and cSID of CP and AA of most barley genotypes were lower when compared to tabulated values. In conclusion, a comprehensive database on chemical composition and SID of CP and AA in eight current barley genotypes has been made available. However, as present SID values are lower compared to feed tables, adjustments are required to minimize the risk of overestimating the actual protein value of barley for pigs.

Monosaccharide transporters in plants: structure, function and physiology.

Monosaccharide transport across the plant plasma membrane plays an important role both in lower and higher plants. Algae can switch between phototrophic and heterotrophic growth and utilize organic compounds, such as monosaccharides as additional or sole carbon sources. Higher plants represent complex mosaics of phototrophic and heterotrophic cells and tissues and depend on the activity of numerous transporters for the correct partitioning of assimilated carbon between their different organs. The cloning of monosaccharide transporter genes and cDNAs identified closely related integral membrane proteins with 12 transmembrane helices exhibiting significant homology to monosaccharide transporters from yeast, bacteria and mammals. Structural analyses performed with several members of this transporter superfamily identified protein domains or even specific amino acid residues putatively involved in substrate binding and specificity. Expression of plant monosaccharide transporter cDNAs in yeast cells and frog oocytes allowed the characterization of substrate specificities and kinetic parameters. Immunohistochemical studies, in situ hybridization analyses and studies performed with transgenic plants expressing reporter genes under the control of promoters from specific monosaccharide transporter genes allowed the localization of the transport proteins or revealed the sites of gene expression. Higher plants possess large families of monosaccharide transporter genes and each of the encoded proteins seems to have a specific function often confined to a limited number of cells and regulated both developmentally and by environmental stimuli.

Cutting, ageing and expression of plant membrane transporters.

The activity and the expression of sucrose, hexose and amino acid transporters were studied with fresh, cut or aged tissues and plasma membrane vesicles (PMV) of mature sugar beet (Beta vulgaris L.) leaves. Cutting and ageing both induced an increase of the transcripts coding for sucrose transporters and hexose transporters. No significant effect could be detected on the amino acid transporter transcripts with the probe used (aap1). A polyclonal serum directed against the Arabidopsis thaliana sucrose transporter (AtSUC1) reacted with a 42 kDa band of the sugar beet PMV, confirming previous biochemical identification of this band as a sucrose transporter. ELISA assays run with microsomal fractions and PMV using the AtSUC1 sucrose transporter probe indicated that ageing, and to a lesser extent cutting, increased the amount of sucrose transporter present in the plasma membrane. However, while cutting strongly stimulated proton-motive force driven uptake of sucrose in PMV, ageing only resulted in a slight stimulation. These data give evidence for transcriptional, post-transcriptional and post-translational controls of the activity of the sucrose transporter by mechanical treatments. Proton-motive force driven uptake of 3-O-methylglucose and valine in PMV was strongly stimulated in PMV from aged tissues, although previous data had shown that cutting did not affect theses processes. Therefore, the plant cells possess various levels of control mechanisms that allow them to regulate fluxes of the main assimilates across the plasma membrane when their natural environment is directly or indirectly altered.

Effect of processing of rapeseed under defined conditions in a pilot plant on chemical composition and standardized ileal amino acid digestibility in rapeseed meal for pigs.

Five rapeseed meals (RSM) were produced from a single batch of rapeseed in a large-scale pilot plant under standardized conditions. The objective was to evaluate the effect of residence time in the desolventizer/toaster (DT) on chemical composition and standardized ileal digestibility (SID) of AA in RSM. Four RSM, with 48, 64, 76, and 93 min residence time and using unsaturated steam in the DT, referred to as RSM48, RSM64, RSM76, and RSM93, respectively, and 1 low-glucosinolate RSM, which was subjected to sequential treatment with unsaturated steam, saturated steam, and dry heat in the DT, referred to as low-GSL RSM, were assayed. Six barrows (average initial BW = 22 ± 1 kg) were surgically fitted with a T-cannula at the distal ileum. Pigs were allotted to a 5 × 6 row × column design with 5 diets and 5 periods. The 5 RSM were included in a cornstarch-casein-based basal diet. In addition, basal ileal endogenous losses and SID of AA originating from casein were determined at the conclusion of the experiment in 2 additional periods by means of the regression method and using 3 graded levels of casein. The SID of AA in the 5 RSM was determined in difference to SID of AA originating from casein. The glucosinolates (GSL) were efficiently reduced, whereas NDF, ADF, ADL, and NDIN contents increased and reactive Lys (rLys) and Lys:CP ratio decreased as the residence time in the DT was increased from 48 to 93 min. The SID of most AA in RSM linearly decreased (P < 0.05) as the residence time in the DT increased from 48 to 93 min. Moreover, there was a linear decrease (P < 0.05) in SID of AA with increasing NDF, ADF, ADL, and NDIN contents in these RSM, whereas SID of AA linearly decreased (P < 0.05) with decreasing levels of GSL and rLys and a decreasing Lys:CP ratio. The decrease (P < 0.05) in SID of AA amounted from 3 up to 6 (percentage units) for most AA, except for SID of Cys and Lys, which decreased by 10 and 11%-units (P < 0.05), respectively, as the residence time in the DT was increased from 48 to 93 min. The SID in low-GSL RSM was for CP and most AA similar to RSM93 but lower ( < 0.05) compared to RSM48. It can be concluded that time and energy-intensive heat treatment results in lower contents of SID AA in RSM together with a reduction in GSL levels. The feed industry would most likely benefit from a rapid and accurate prediction of SID of AA, for example, based on content of NDIN, GSL, rLys or on Lys:CP ratio, in different batches of RSM used for feed manufacturing.

Standardized ileal digestibility of amino acids in eight genotypes of soft winter wheat fed to growing pigs.

A study with growing pigs was conducted to determine the chemical composition and standardized ileal digestibility (SID) of CP and AA of 8 wheat genotypes that have recently been added to the German Descriptive Variety List. These genotypes included Tabasco, KWS Erasmus, Tobak, Skalmeje, Mulan, Event, Tommi, and Adler. The 8 genotypes were grown under identical environmental conditions on the same site, and they were harvested and processed under the same conditions. Nine barrows with an initial BW of 32 ± 2 kg were surgically fitted with simple ileal T-cannulas and allotted to a row-column design with 9 pigs and 8 periods of 6 d each. Wheat was the sole dietary source of CP and AA. Among the 8 wheat genotypes, contents of CP ranged from 10.9 to 13.3% (as-fed basis), whereas contents of total nonstarch polysaccharides ranged from 8.0 to 9.4% (as-fed basis). The SID of CP in the 8 genotypes ranged from 83 to 87%, with greatest ( = 0.01) values for Event and lowest ( = 0.01) for all other wheat genotypes. Intermediate SID of CP values were obtained for Adler and KWS Erasmus. For Lys, greater ( < 0.05) SID was observed in Adler (73%) and KWS Erasmus (74%) in comparison to Tommi, Tobak, and Mulan (69%). Adler had greater SID of Met (88%; = 0.01) when compared to Tabasco (86%); Tobak, Skalmeje, and Mulan (85%); and Tommi (84%). Among the 8 wheat genotypes, standardized ileal digestible content (cSID) of CP followed total CP content and ranged from 9.1 to 11.3% (as-fed basis). Standardized ileal digestible content of both CP and AA were greater ( < 0.001) in Adler compared to all other genotypes. For most AA, Tabasco had the lowest ( < 0.001; except for His, Trp, Asp, and Cys) cSID values of all wheat genotypes. The cSID of CP decreased ( < 0.001) as the starch content in the 8 wheat genotypes increased, but cSID of CP increased ( < 0.001) as the CP content in the 8 genotypes increased. Because SID and cSID of CP and most AA increased ( < 0.05) with lower test weight and falling number, these variables may aid to predict SID and cSID in wheat batches, whereas other nutrients such as fiber fractions are not suitable due to low variation among the 8 genotypes. The present study provides a comprehensive database on nutritional composition and SID of CP and AA of 8 wheat genotypes grown under identical conditions. Because the SID values in these genotypes are lower when compared to literature data, digestibility values in actual feed tables for wheat may overestimate their protein values and need to be updated.