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Adverse drug reactions frequently involve the gastrointestinal tract. We present two cases of colitis that occurred months to years after chemotherapy and autologous stem cell transplantation for the treatment of lymphoma. Laboratory tests revealed altered immune status with decreased CD4/CD8 ratio and hypogammaglobinemia (in one patient). The patients had no history of inflammatory bowel disease or immunodeficiency. Biopsies showed chronic active colitis with crypt architectural distortion, erosions, and ulcers as well as pyloric gland metaplasia and loss of plasma cells (in one patient, respectively). Colitis appeared to be related to lymphoma therapy, but could not be attributed to a distinct drug or infectious agent, suggesting the concept of persistent immune dysregulation driving mucosal inflammation. Hence, we suggest "immune dysregulation-associated colitis" (ID-colitis) as an umbrella term for cases of chronic colitis, in which immune dysfunction is evident from blood samples or clinical information and inflammatory bowel disease has been ruled out., Competing Interests: Declarations. Ethics approval: Not applicable. Consent to participate: The patients provided written informed consent. Consent for publication: Informed consent for publication was obtained from all authors. Conflicts of interest: The authors declare no competing interests., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Natural plant populations are polymorphic and show intraspecific variation in resistance properties against pathogens. The activation of the underlying defence responses can depend on variation in perception of pathogen-associated molecular patterns or elicitors. To dissect such variation, we evaluated the responses induced by laminarin (a glucan, representing an elicitor from oomycetes) in the wild tomato species Solanum chilense and correlated this to observed infection frequencies of Phytophthora infestans. We measured reactive oxygen species burst and levels of diverse phytohormones upon elicitation in 83 plants originating from nine populations. We found high diversity in basal and elicitor-induced levels of each component. Further we generated linear models to explain the observed infection frequency of P. infestans. The effect of individual components differed dependent on the geographical origin of the plants. We found that the resistance in the southern coastal region, but not in the other regions, was directly correlated to ethylene responses and confirmed this positive correlation using ethylene inhibition assays. Our findings reveal high diversity in the strength of defence responses within a species and the involvement of different components with a quantitatively different contribution of individual components to resistance in geographically separated populations of a wild plant species., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Society for Experimental Biology.)

Altering plant water use efficiency (WUE) is a promising approach for achieving sustainable crop production in changing climate scenarios. Here, we show that WUE can be tuned by alleles of a single gene discovered in elite maize (Zea mays) breeding material. Genetic dissection of a genomic region affecting WUE led to the identification of the gene ZmAbh4 as causative for the effect. CRISPR/Cas9-mediated ZmAbh4 inactivation increased WUE without growth reductions in well-watered conditions. ZmAbh4 encodes an enzyme that hydroxylates the phytohormone abscisic acid (ABA) and initiates its catabolism. Stomatal conductance is regulated by ABA and emerged as a major link between variation in WUE and discrimination against the heavy carbon isotope (Δ13C) during photosynthesis in the C4 crop maize. Changes in Δ13C persisted in kernel material, which offers an easy-to-screen proxy for WUE. Our results establish a direct physiological and genetic link between WUE and Δ13C through a single gene with potential applications in maize breeding., (© The Author(s) 2022. Published by Oxford University Press on behalf of American Society of Plant Biologists.)

Application of the sensomics concept on dried scallops, a Japanese specialty produced from the adductor muscle of scallops, revealed after activity-guided fractionation with subsequent (comparative) taste dilution analyses besides nucleotides, amino acids, organic acids, and inorganic ions, the presence of taste-modulating quaternary ammonium compounds and opines in highly taste-active fractions. In order to recreate the taste of dried scallops, two independent quantitation approaches were applied and compared. The first approach used multiple targeted UHPLC-MS/MS and high-performance ion chromatography methods. Besides already established quantitation methods for basic taste compounds, a new HILIC-UHPLC-MS/MS MRM method for the quantitation of chromatographically challenging opines, using synthesized stable isotope-labeled standards, was developed. Furthermore, a qHNMR approach was applied, enabling a direct identification and quantitation of organic taste compounds in a food extract without prior fractionation using a reference 1 H NMR database. Both methods yielded similar quantitative results of taste-active compounds in dried scallop extracts and subsequent taste recombination experiments based on these data were able to recreate the taste of dried scallops.

The quantitative determination of putative taste active metabolites, the ranking of these compounds in their sensory impact based on dose-overthreshold (DoT) factors, followed by confirmation of their relevance by reconstitution and omission experiments enables the decoding of the non-volatile sensometabolome of certain foods. The identification and quantitation of target taste compounds by liquid chromatography-tandem mass spectrometry (LC-MS/MS), high-performance liquid chromatography-ultraviolet/visible (HPLC-UV/Vis) spectroscopy, or high-performance ion chromatography (HPIC) is often laborious and time-consuming. In this work, we present a novel quantitative 1 H NMR approach for reconstituting basic taste recombinants of different foods, including apple juice, balsamic vinegar, golden chanterelles, process flavor, and shrimp. Compound identification using the taste recombinant database, followed by absolute quantitation via quantitative 1 H NMR (qHNMR), enables a fast and direct reconstitution of basic taste recombinants. The taste profile analysis of basic taste recombinants was generated via qHNMR in less than 15 min and compared with literature data acquired by LC-MS/MS and/or HPLC-UV/Vis and revealed identical results for all taste qualities. A determination of limit of detection (LoD) values for S/N = 50 of various proton signals with different integrals and multiplicities demonstrated that taste recognition thresholds of all basic tastants are far above those of LoD concentrations under the chosen conditions. Therefore, our experimental setup is able to detect basic taste-active compounds well below their taste recognition thresholds.

Plant specialised metabolites constitute a layer of chemical defence. Classes of the defence compounds are often restricted to a certain taxon of plants, e.g. benzoxazinoids (BX) are characteristically detected in grasses. BXs confer wide-range defence by controlling herbivores and microbial pathogens and are allelopathic compounds. In the crops maize, wheat and rye high concentrations of BXs are synthesised at an early developmental stage. By transfer of six Bx-genes (Bx1 to Bx5 and Bx8) it was possible to establish the biosynthesis of 2,4-dihydroxy-1,4-benzoxazin-3-one glucoside (GDIBOA) in a concentration of up to 143 nmol/g dry weight in Arabidopsis thaliana. Our results indicate that inefficient channeling of substrates along the pathway and metabolisation of intermediates in host plants might be a general drawback for transgenic establishment of specialised metabolite biosynthesis pathways. As a consequence, BX levels required for defence are not obtained in Arabidopsis. We could show that indolin-2-one (ION), the first specific intermediate, is phytotoxic and is metabolised by hydroxylation and glycosylation by a wide spectrum of plants. In Arabidopsis, metabolic stress due to the enrichment of ION leads to elevated levels of salicylic acid (SA) and in addition to its intrinsic phytotoxicity, ION affects plant morphology indirectly via SA. We could show that Bx3 has a crucial role in the evolution of the pathway, first based on its impact on flux into the pathway and, second by C3-hydroxylation of the phytotoxic ION. Thereby BX3 interferes with a supposedly generic detoxification system towards the non-specific intermediate., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Scope: Alternaria fungi are widely distributed plant pathogens infecting grains and vegetables and causing major harvest losses in the field and during postharvest storage. Besides, consumers are endangered by the formation of toxic secondary metabolites. Some of these secondary metabolites are chemically characterized as mycotoxins, but the majority of the Alternaria mycobolome still remains unknown., Methods and Results: Fourier-transform ion cyclotron resonance mass spectrometry (FTICR-MS) and LC-MS/MS are combined for the non-targeted and targeted analysis of the metabolome of three A. alternata isolates and one A. solani isolate. Due to the ultra-high resolution of FTICR-MS, unique molecular formulae are assigned to measured m/z signals. The molecular formulae are matched to entries of the databases Antibase and Kyoto Encyclopedia of Genes and Genomes. The non-targeted analysis of the fungal extracts reveals variations in the secondary metabolite profile of A. alternata and A. solani. Differences in the biosynthesis of dibenzo-α-pyrones, perylene quinones, tentoxin, and tenuazonic acid of the A. alternata and A. solani isolates are determined applying targeted LC-MS/MS., Conclusion: FTICR-MS analyses reveal clear differences in the metabolic profile of the A. solani and the A. alternata isolates., (© 2019 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Plant cells are encased in a semi-rigid cell wall of complex build. As a consequence, cell wall remodeling is essential for the control of growth and development as well as the regulation of abiotic and biotic stress responses. Plant cells actively sense physico-chemical changes in the cell wall and initiate corresponding cellular responses. However, the underlying cell wall monitoring mechanisms remain poorly understood. In Arabidopsis the atypical receptor kinase STRUBBELIG (SUB) mediates tissue morphogenesis. Here, we show that SUB-mediated signal transduction also regulates the cellular response to a reduction in the biosynthesis of cellulose, a central carbohydrate component of the cell wall. SUB signaling affects early increase of intracellular reactive oxygen species, stress gene induction as well as ectopic lignin and callose accumulation upon exogenous application of the cellulose biosynthesis inhibitor isoxaben. Moreover, our data reveal that SUB signaling is required for maintaining cell size and shape of root epidermal cells and the recovery of root growth after transient exposure to isoxaben. SUB is also required for root growth arrest in mutants with defective cellulose biosynthesis. Genetic data further indicate that SUB controls the isoxaben-induced cell wall stress response independently from other known receptor kinase genes mediating this response, such as THESEUS1 or MIK2. We propose that SUB functions in a least two distinct biological processes: the control of tissue morphogenesis and the response to cell wall damage. Taken together, our results reveal a novel signal transduction pathway that contributes to the molecular framework underlying cell wall integrity signaling., Competing Interests: The authors have declared that no competing interests exist.

To map qualitative and quantitative metabolome alterations when Penicillium roqueforti is grown in an environment where l-tyrosine levels are perturbed, the recently established differential off-line LC-NMR (DOLC-NMR) approach was successfully applied in connection with an absolute metabolite quantitation using a quantitative 1 H NMR protocol following the ERETIC 2 (Electronic REference To access In vivo Concentrations) methodology. Among the 23 influenced metabolites, amino acid degradation products like 2-(4-hydroxyphenyl)acetic acid and 2-(3,4-dihydroxyphenyl)acetic acid underwent a tremendous upregulation in the amino acid perturbed approach. Moreover, the output of secondary metabolites like andrastin A, eremofortin B, and the tetrapeptide d-Phe-l-Val-d-Val-l-Tyr was affected in the case of the presence or absence of the added aromatic amino acid. Furthermore, the isolated secondary metabolites of P. roqueforti have been quantified for the first time in five divergent Penicillium isolates by means of a validated LC-ECHO-MS/MS method. This technique is used to compensate the effect of co-extracted matrix compounds during the analysis and to utilize quasi-internal standards to quantify all metabolites of interest accurately. This screening outlined the great variety between the different fungi of the same species. The metabolite spectra of wild-type fungi included more toxic intermediates compared to a selected fungi used as a starter culture for blue-mold cheese production. In addition, these secondary metabolites were quantified in commercially available white- and blue-mold cheese samples. The main differences between the analyte profiles of white and blue cheeses were linked to the impact of the used starter culture. Specific metabolites detected from P. roqueforti like andrastin A and B or roquefortine C could not be detected in white cheese. Among the blue cheese samples, different metabolite pattern could be observed regarding various P. roqueforti starter cultures.

UPLC-TOF/MS profiling, followed by the recently reported differential off-line LC-NMR (DOLC-NMR) and quantitative 1 H NMR spectroscopy (qHNMR), led to the differential qualitative analysis and accurate quantitation of l-tryptophan-induced metabolome alterations of Penicillium roqueforti, which is typically used in making blue-mold cheese. Among the 24 metabolites identified, two tetrapeptides, namely, d-Phe-l-Val-d-Val-l-Tyr and d-Phe-l-Val-d-Val-l-Phe, as well as cis-bis(methylthio)silvatin, are reported for the first time as metabolites of P. roqueforti. Antimicrobial activity tests showed strong effects of the catabolic l-tryptophan metabolites 3-hydroxyanthranilic acid, anthranilic acid, and 3-indolacetic acid against Saccharomyces cerevisiae, with IC 50 values between 15.6 and 24.0 μg/mL, while roquefortine C and cis-bis(methylthio)silvatin inhibited the growth of Gram-negative Escherichia coli and Gram-positive Bacillus subtilis with IC 50 values between 30.0 and 62.5 μg/mL.

A novel differential off-line LC-NMR approach (DOLC-NMR) was developed to capture and quantify nutrient-induced metabolome alterations in Saccharomyces cerevisiae. Off-line coupling of HPLC separation and 1 H NMR spectroscopy supported by automated comparative bucket analyses, followed by quantitative 1 H NMR using ERETIC 2 (electronic reference to access in vivo concentrations), has been successfully used to quantitatively record changes in the metabolome of S. cerevisiae upon intervention with the aromatic amino acid l-tyrosine. Among the 33 metabolites identified, glyceryl succinate, tyrosol acetate, tyrosol lactate, tyrosol succinate, and N-acyl-tyrosine derivatives such as N-(1-oxooctyl)-tyrosine are reported for the first time as yeast metabolites. Depending on the chain length, N-(1-oxooctyl)-, N-(1-oxodecanyl)-, N-(1-oxododecanyl)-, N-(1-oxomyristinyl)-, N-(1-oxopalmityl)-, and N-(1-oxooleoyl)-l-tyrosine imparted a kokumi taste enhancement above their recognition thresholds ranging between 145 and 1432 μmol/L (model broth). Finally, carbon module labeling (CAMOLA) and carbon bond labeling (CABOLA) experiments with 13 C 6 -glucose as the carbon source confirmed the biosynthetic pathway leading to the key metabolites; for example, the aliphatic side chain of N-(1-oxooctyl)-tyrosine could be shown to be generated via de novo fatty acid biosynthesis from four C 2 -carbon modules (acetyl-CoA) originating from glucose.

Introduction: Facing the rapid scale-up of antiretroviral treatment (ART) programs in resource-limited settings, monitoring of treatment outcome is essential in order to timely detect and tackle drawbacks [1]., Methods: In a prospective cohort study, 300 consecutive patients starting first-line ART were enrolled between 2009 and2010 in a large HIV treatment centre in rural Cameroon. Patients were followed up for 12 months. Virologic failure was defined as a VL >1000 cop/mL at month 12. Besides CD4 and viral load (VL) analysis, HIV-1 drug resistance testing was performed in patients with VL>1000 copies (c)/mL plasma. In those patients and controls, minority HIV-1 drug resistance mutations at baseline, and plasma drug levels were analyzed in order to identify the risk factors for virologic failure., Results: Most enrolled patients (71%) were female. At baseline median CD4 cell count was 162/µL (IQR 59-259), median log10 VL was 5.4 (IQR 5.0-5.8) c/mL, and one-third of patients had World Health Organisation (WHO) stage 3 or 4; 30 patients died during follow-up. Among all patients who completed follow-up 38/238 had virologic failure. These patients were younger, had lower CD4 cell counts and more often had WHO stage 3 or 4 at baseline compared to patients with VL<1000c/mL. Sixty-three percent of failing patients (24/38) had at least one mutation associated with high-level drug resistance. The M184V mutation was the most frequently detected nucleoside reverse transcriptase inhibitor (NRTI) mutation (n=18) followed by TAMs (n=5) and multi-NRTI resistance mutations (n=4). The most commonly observed non-nucleoside reverse-transcriptase inhibitor (NNRTI) resistance mutations were K103N (n=10), Y181C (n=7), and G190A (n=6). Drug resistance mutations at baseline were detected in 12/65 (18%) patients, in 6 patients with and 6 patients without virological failure (p=0.77). Subtherapeutic NNRTI levels (OR 6.67, 95% CI 1.98-22.43, p<0.002) and poorer adherence (OR 1.54, 95% CI 1.00-2.39, p=0.05) were each associated with higher risk of virologic failure in the matched pair analysis. Unavailability of ART at the treatment centre was the single most common cause (37%) for incomplete adherence in these patients., Conclusions: Virologic failure after one year of first-line ART in rural Cameroon was not associated with transmitted drug resistance, but with reduced drug plasma levels and incomplete adherence. Strategies to assure adherence and uninterrupted drug supply are important factors for therapy success.

Background: In Africa, success of antiretroviral treatment (ART) seems to lag behind in children compared with adults, and high therapeutic failure rates have been reported. We aimed to identify prevalence and determinants of virological failure in HIV-infected children treated under programmatic conditions., Methods: All patients <18 years on ART presenting to the HIV clinic at the Bamenda Regional Hospital, a secondary referral hospital in rural Cameroon, from September 2010 to August 2011, were enrolled in this cross-sectional study. Clinical data, self-reported adherence, CD4(+) T-cell counts and viral load were recorded. Therapeutic drug monitoring was performed on stored plasma samples. Determinants of virological failure were identified using descriptive statistics and logistic regression., Results: A total of 230 children with a mean age of 8.9 years (sd 3.7) were included. At the time of analysis, the mean duration of HAART was 3.5 years (sd 1.7) and 12% had a CD4(+) T-cell count <200 cells/µl. In total, 53% of children experienced virological failure (>200 copies/ml). Among children on nevirapine (NVP), plasma levels were subtherapeutic in 14.2% and supratherapeutic in 42.2%. Determinants of virological failure included male sex, lower CD4(+) T-cell counts, subtherapeutic drug levels, longer time on ART and a deceased mother. Poor adherence was associated with subtherapeutic NVP plasma levels and advanced disease stages (WHO stage 3/4)., Conclusions: This study demonstrates high virological failure rates and a high variability of NVP plasma levels among HIV-infected children in a routine ART programme in rural Cameroon. Strategies to improve adherence to ART in HIV-infected children are urgently needed.

The challenge of managing pediatric foot injuries is the identification of the rare injuries that require operative treatment and the management of complications such as compartment syndrome, post-traumatic foot deformities, and avascular necrosis. With these complications in mind, the authors discuss fractures of the talus, calcaneus, lesser tarsal bones, Lisfranc's joint, metarsals, and phalanges. Dislocation of metatarsophalangeal or interphalangeal joints is also discussed.

Purpose: The aim of this study was to describe typical age-related sonographic features of the Achilles tendon and calcaneal apophysis in children, providing a reference for the assessment of heel pathologies during the growth period., Methods: The calcaneal apophysis and Achilles tendon insertion of 100 children 2 months to 18 years old were examined by high-frequency gray-scale and color Doppler sonography along both the longitudinal and transverse planes. The thicknesses of the apophyseal cartilage at the calcaneal tuberosity and of the Achilles tendon were measured. Also, the sonographic appearance of the bone-cartilage interface was studied., Results: In children 2 months to 3 years old, the cartilage of the calcaneal tuberosity apophysis was anechoic, with small scattered echoes. In 19 of these 25 children (76%), the echogenic areas contained at least 1 small vessel, visualized on color Doppler sonography. In 15 of 25 children (60%) 4-6 years old, a wavy interface was noted at the junction of the calcaneus and the apophyseal cartilage., Conclusions: High-frequency sonography can yield reliable information about the bone-cartilage interface and the Achilles tendon insertion site at the calcaneal tuberosity in children. The sonographic features of the normal heel described here may contribute to improved assessment of pathologies in this anatomic region., (Copyright 2004 Wiley Periodicals, Inc.)

Chlorogenic acid derivatives are potent inhibitors of hepatic glucose production by inhibition of the glucose-6-phosphate translocase component of the hepatic glucose-6-phosphatase system. The pharmacological proof of concept was clearly demonstrated during i.v. infusion of potent derivatives (S 4048, S 3483) in rats. However, the blood glucose lowering effect of S 4048 after bolus i.v. injection lasted only 60-90 min. Plasma clearance of S 4048 was very high, and the parent compound was rapidly and efficiently excreted into the bile of Wistar and GY/TR(-) rats, indicating that mrp-2 was not involved in this hepatobiliary elimination process. About 72% of the total administered radioactivity appeared in the bile within 20 min after i.v. bolus injection of the radiolabeled analogue [(3)H]S 1743 in a Wistar rat. However, in GY/TR(-) rats the dicarboxylic analogue of S 4048, S 3025, was cleared from the plasma less rapidly than its parent compound and its biliary elimination was comparatively low. In contrast, S 3025 exhibited comparable pharmacokinetics and biliary elimination profile as S 4048 in Wistar rats, suggesting that biliary elimination of S 3025 is facilitated by mrp-2, functionally absent in GY/TR(-) rats. Targeting to mrp-2 resulted in a significantly prolonged reduction of blood glucose levels in GY/TR(-) rats after i.v. bolus administration of S 3025.