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1.
Metabolites ; 14(5)2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38786728

ABSTRACT

Phytohormones that trigger or repress flower meristem development in apple buds are thought to be locally emitted from adjacent plant tissues, including leaves and fruitlets. The presence of fruitlets is known to inhibit adjacent buds from forming flowers and thus fruits. The resulting absence of fruitlets the following season restores flower-promoting signalling to the new buds. The cycle can lead to a biennial bearing behaviour of alternating crop loads in a branch or tree. The hormonal stimuli that elicit flowering is typically referred to as the floral induction (FI) phase in bud meristem development. To determine the metabolic pathways activated in FI, young trees of the cultivar 'Ruby Matilda' were subjected to zonal crop load treatments imposed to two leaders of bi-axis trees in the 2020/2021 season. Buds were collected over the expected FI phase, which is within 60 DAFB. Metabolomics profiling was undertaken to determine the differentially expressed pathways and key signalling molecules associated with FI in the leader and at tree level. Pronounced metabolic differences were observed in trees and leaders with high return bloom with significant increases in compounds belonging to the cytokinin, abscisic acid (ABA), phenylpropanoid and flavanol chemical classes. The presence of cytokinins, namely adenosine, inosine and related derivatives, as well as ABA phytohormones, provides further insight into the chemical intervention opportunities for future crop load management strategies via plant growth regulators.

2.
Biomolecules ; 14(4)2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38672431

ABSTRACT

Safflower (Carthamus tinctorius L.) is an ancient oilseed crop of interest due to its diversity of end-use industrial and food products. Proteomic and metabolomic profiling of its organs during seed development, which can provide further insights on seed quality attributes to assist in variety and product development, has not yet been undertaken. In this study, an integrated proteome and metabolic analysis have shown a high complexity of lipophilic proteins and metabolites differentially expressed across organs and tissues during seed development and petal wilting. We demonstrated that these approaches successfully discriminated safflower reproductive organs and developmental stages with the identification of 2179 unique compounds and 3043 peptides matching 724 unique proteins. A comparison between cotyledon and husk tissues revealed the complementarity of using both technologies, with husks mostly featuring metabolites (99%), while cotyledons predominantly yielded peptides (90%). This provided a more complete picture of mechanisms discriminating the seed envelope from what it protected. Furthermore, we showed distinct molecular signatures of petal wilting and colour transition, seed growth, and maturation. We revealed the molecular makeup shift occurring during petal colour transition and wilting, as well as the importance of benzenoids, phenylpropanoids, flavonoids, and pigments. Finally, our study emphasizes that the biochemical mechanisms implicated in the growing and maturing of safflower seeds are complex and far-reaching, as evidenced by AraCyc, PaintOmics, and MetaboAnalyst mapping capabilities. This study provides a new resource for functional knowledge of safflower seed and potentially further enables the precision development of novel products and safflower varieties with biotechnology and molecular farming applications.


Subject(s)
Carthamus tinctorius , Flowers , Metabolomics , Plant Proteins , Proteomics , Seeds , Carthamus tinctorius/metabolism , Carthamus tinctorius/growth & development , Carthamus tinctorius/genetics , Seeds/metabolism , Seeds/growth & development , Metabolomics/methods , Proteomics/methods , Plant Proteins/metabolism , Plant Proteins/genetics , Flowers/metabolism , Flowers/growth & development
3.
Gerontol Geriatr Med ; 10: 23337214241234737, 2024.
Article in English | MEDLINE | ID: mdl-38410616

ABSTRACT

Objective: This study tested the hypothesis that healthy aging attenuates cognitive practice effects and, consequently, limits the familiarity-associated reductions in heart rate (HR) and breathing frequency (BF) responses during retesting. Methods: Twenty-one cognitively normal older and younger adults (65 ± 2 vs. 26 ± 1 years old) participated in the study. Mini-Mental State Examination (MMSE), Digit-Span-Test (DST), Trail Making Test (TMT-B), and California Verbal Learning Test (CVLT-II) were administered twice at 3-week intervals, while HR and BF were monitored by electrocardiography and plethysmography, respectively. Results: Cognitive performances were not affected by the age factor, and the retest factor only affected CVLT-II. HR and BF increased only in the younger adults (p < .01) during cognitive tests; retesting attenuated these responses (retest factor p < .01). Long-delay free-recall in CVLT-II was unchanged in cognitively normal older versus younger adults. Healthy aging did not diminish short-term memory assessed by DST and CVLT-II short-delay or long-delay free-recalls. Conclusions: Only CVLT-II, but not MMSE, DST or TMT-B, demonstrated cognitive retesting practice effects in the younger and older adults. Cognitive testing at 3-week intervals in cognitively normal older and younger subjects revealed divergent cardiorespiratory responses to MMSE, DST, and TMT-B cognitive testing, particularly HR, which increased only in younger adults and to a lesser extent during retesting despite the absence of practice effects.

4.
Otol Neurotol ; 45(2): e78-e83, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38082459

ABSTRACT

OBJECTIVE: Explore the effects of hearing loss on social life and identify residual social life deficits that remain after cochlear implantation. STUDY DESIGN: Retrospective review of prospectively obtained data. SETTING: Tertiary care adult neurotology center. PATIENTS: Adults between the ages of 35 and 83 years were included with either normal hearing (NH) or a cochlear implant (CI). INTERVENTIONS: CI and non-CI-specific quality-of-life (QOL) surveys focused on social and overall QOL. MAIN OUTCOME MEASURES: (1) The difference in QOL survey responses between NH and CI participants. (2) The relationship between CI-specific global and social QOL responses and non-CI-specific social QOL responses in CI users. RESULTS: A total of 51 participants were included: 31 CI users and 20 NH participants. Of the social QOL questionnaires, CI users reported significantly poorer scores on Self-Efficacy in Social Interactions than NH peers ( p = 0.049). Both Self-Efficacy in Social Interactions scores and Social Isolation Questionnaire scores were significantly correlated with the CI-specific social domain of QOL ( r = 0.64 and -0.58, respectively). Only the Self-Efficacy in Social Interactions scores had a moderate association with global CI QOL ( r = 0.47). CONCLUSIONS: CI users self-report similar social life outcomes as their NH peers with the exception of poorer self-efficacy in social situations. Moreover, self-efficacy in social interactions and social isolation were associated with social QOL in CI users, and self-efficacy in social interactions was associated with broader CI-related QOL. Findings support the relevance of individuals' perception of social life to their overall QOL with a CI.


Subject(s)
Cochlear Implantation , Cochlear Implants , Deafness , Hearing Loss , Speech Perception , Adult , Humans , Middle Aged , Aged , Aged, 80 and over , Quality of Life , Hearing Loss/surgery , Deafness/surgery , Speech Perception/physiology
5.
J Environ Radioact ; 272: 107330, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38000220

ABSTRACT

Screening of aqueous samples for 3H contamination is required to decide suitability of water intended for human consumption during radiation emergency. BARC, Trombay has recently procured Portable Triathler liquid scintillation counter as a screening tool for on-site response to radiation emergency. For this purpose, parameters like, different available scintillators, scintillator to sample ratio and influence of different capacity scintillation vials were optimized for 3H concentration measurement. The study indicated that for 7 mL vials, the optimized scintillator to sample ratio was 4:1 for Optiphase Hisafe II, Ultima Gold Ultra Low Level Tritium, Aqualight AB and Dioxane based scintillators whereas for Ultima Gold AB and Optiphase Hisafe III scintillators it was 3:1. In case of 20 mL vials, the ratio was optimized to 8:1 for all the above mentioned six scintillators. Additionally, the effect of applying counting efficiency using calibration curves generated using distilled water and that obtained using optimized scintillator to sample ratio in various spiked water samples was also studied. Results in 3H concentration (2000-5700 Bq/mL) indicate about ±10% deviation using both the methods for commercially available scintillators. However, in case of Dioxane based scintillator, the deviation was higher (20%). For analysis of 3H concentration ∼200 Bq/mL using commercially available scintillators results in higher deviation of about 21% due to unreliable quench indicating parameter for count rate less than 4000. The study indicated that calibration curves constructed using optimized parameters are universally applicable for determination of 3H concentration in wide variety of water samples.


Subject(s)
Drinking Water , Radiation Monitoring , Humans , Tritium , Scintillation Counting/methods , Dioxanes
6.
NPJ Breast Cancer ; 9(1): 67, 2023 Aug 11.
Article in English | MEDLINE | ID: mdl-37567880

ABSTRACT

The combination of Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) and endocrine therapy (ET) is the standard of care for hormone receptor-positive (HR + ), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC). Currently, there are no robust biomarkers that can predict response to CDK4/6i, and it is not clear which patients benefit from this therapy. Since MBC patients with liver metastases have a poorer prognosis, developing predictive biomarkers that could identify patients likely to respond to CDK4/6i is clinically important. Here we show the ability of imaging texture biomarkers before and a few cycles after CDK4/6i therapy, to predict early response and overall survival (OS) on 73 MBC patients with known liver metastases who received palbociclib plus ET from two sites. The delta radiomic model was associated with OS in validation set (HR: 2.4; 95% CI, 1.06-5.6; P = 0.035; C-index = 0.77). Compared to RECIST response, delta radiomic features predicted response with area under the curve (AUC) = 0.72, 95% confidence interval (CI) 0.67-0.88. Our study revealed that radiomics features can predict a lack of response earlier than standard anatomic/RECIST 1.1 assessment and warrants further study and clinical validation.

7.
Metabolites ; 13(2)2023 Jan 30.
Article in English | MEDLINE | ID: mdl-36837825

ABSTRACT

Perennial ryegrass (Lolium perenne L.), an economically important pasture and turf grass, is commonly infected with asexual Epichloë species endophytes. Endophytes provide enhanced bioprotection by producing alkaloids, and research often focusses on the negative impact on grazing animals. However, alkaloid distribution throughout the plant and their role in biocontrol of insect pests and diseases are less well understood. Additionally, intermediate compounds have not been investigated for their impacts on animal welfare and biological control in pasture-based scenarios. Here, a single liquid chromatography-mass spectrometry (LC-MS) method was used to measure seven alkaloids in different perennial ryegrass tissues infected with SE or NEA12 endophytes. High alkaloid recoveries and a clear plant matrix effect emphasize the importance of using matrix-matched standards for accurate quantitation. The method is sensitive, detecting alkaloids at low concentrations (nanogram levels), which is important for endophyte strains that produce compounds detrimental to livestock. Concentrations were generally highest in seeds, but distribution differed in the shoots/roots: peramine, terpendole E, terpendole C and lolitrem B were higher in shoots, whilst ergovaline, paxilline and epoxy-janthitrem I were more evenly distributed throughout the two tissues. Knowledge of alkaloid distribution may allow for concentrations to be predicted in roots based on concentrations in the shoots, thereby assisting future determinations of resistance to insects, especially subterranean root-feeding pests.

8.
Sensors (Basel) ; 23(4)2023 Feb 06.
Article in English | MEDLINE | ID: mdl-36850417

ABSTRACT

The detection of beneficial microbes living within perennial ryegrass seed causing no apparent defects is challenging, even with the most sensitive and conventional methods, such as DNA genotyping. Using a near-infrared hyperspectral imaging system (NIR-HSI), we were able to discriminate not only the presence of the commercial NEA12 fungal endophyte strain but perennial ryegrass cultivars of diverse seed age and batch. A total of 288 wavebands were extracted for individual seeds from hyperspectral images. The optimal pre-processing methods investigated yielded the best partial least squares discriminant analysis (PLS-DA) classification model to discriminate NEA12 and without endophyte (WE) perennial ryegrass seed with a classification accuracy of 89%. Effective wavelength (EW) selection based on GA-PLS-DA resulted in the selection of 75 wavebands yielding 88.3% discrimination accuracy using PLS-DA. For cultivar identification, the artificial neural network discriminant analysis (ANN-DA) was the best-performing classification model, resulting in >90% classification accuracy for Trojan, Alto, Rohan, Governor and Bronsyn. EW selection using GA-PLS-DA resulted in 87 wavebands, and the PLS-DA model performed the best, with no extensive compromise in performance, resulting in >89.1% accuracy. The study demonstrates the use of NIR-HSI reflectance data to discriminate, for the first time, an associated beneficial fungal endophyte and five cultivars of perennial ryegrass seed, irrespective of seed age and batch. Furthermore, the negligible effects on the classification errors using EW selection improve the capability and deployment of optimized methods for real-time analysis, such as the use of low-cost multispectral sensors for single seed analysis and automated seed sorting devices.


Subject(s)
Hyperspectral Imaging , Lolium , Cell Movement , Diagnostic Imaging , Seeds
9.
Int J Mol Sci ; 23(11)2022 May 27.
Article in English | MEDLINE | ID: mdl-35682698

ABSTRACT

The triggers of biennial bearing are thought to coincide with embryonic development in apple and occurs within the first 70 days after full bloom (DAFB). Strong evidence suggests hormonal signals are perceived by vegetative apple spur buds to induce flowering. The hormonal response is typically referred to as the floral induction (FI) phase in bud meristem development. To determine the metabolic pathways activated in FI, young trees of the biennial bearing cultivar 'Nicoter' and the less susceptible cultivar 'Rosy Glow' were forced into an alternate cropping cycle over five years and an inverse relationship of crop load and return bloom was established. Buds were collected over a four-week duration within 70 DAFB from trees that had maintained a four-year biennial bearing cycle. Metabolomics profiling was undertaken to determine the differentially expressed pathways and key signalling molecules associated with biennial bearing. Marked metabolic differences were observed in trees with high and low crop load treatments. Significant effects were detected in members of the phenylpropanoid pathway comprising hydroxycinnamates, salicylates, salicylic acid biosynthetic pathway intermediates and flavanols. This study identifies plant hormones associated with FI in apples using functional metabolomics analysis.


Subject(s)
Malus , Flowers/metabolism , Gene Expression Regulation, Plant , Malus/metabolism , Metabolic Networks and Pathways , Plant Growth Regulators/metabolism , Plant Proteins/genetics , Trees/metabolism
10.
Appl Radiat Isot ; 186: 110297, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35623136

ABSTRACT

A rapid radiochemical method has been developed for estimation of plutonium and americium in nasal swab using extractive liquid scintillation spectrometry. The method involves solvent extraction of plutonium and americium from pre-treated nasal swab using 0.2 M Di-(2-ethylhexyl)phosphoricacid prepared in toluene scintillator & back extraction of americium in aqueous phase using 0.35 M HNO3. Activity assessment was carried out using liquid scintillation spectrometry. Overall recovery obtained was 96% for plutonium and 76% for americium with a sample turnaround time of 3 h.


Subject(s)
Americium , Plutonium , Americium/analysis , Plutonium/analysis , Radiometry , Solvents , Spectrum Analysis/methods
11.
Eur Radiol ; 32(9): 6230-6237, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35389048

ABSTRACT

OBJECTIVES: The objective of this study is to retrospectively evaluate the use of ultrasound-guided continuous radiofrequency (CRF) lesioning of the suprascapular nerve for treating chronic shoulder pain, due to osteoarthritis. We describe a modified distal and selective ablation technique in the spinoglenoid notch, with motor and sensory stimulation, which protects the motor branch of the nerve from ablation. METHODS: A retrospective analysis was performed of patients, who underwent ultrasound-guided CRF lesioning of the suprascapular nerve from October 2013 to January 2020. During the procedure, the CRF electrode is placed in the spinoglenoid notch, at the distal suprascapular nerve capsular branch. Motor and sensory stimulations are used to confirm the position. CRF lesioning is applied up to three times, at 3 different points, for 1 min each time, at 80° C. RESULTS: In total, 127 first CRF suprascapular nerve lesioning procedures were performed on 101 patients with chronic shoulder pain secondary to osteoarthritis. One hundred nineteen diagnostic ultrasound-guided suprascapular nerve corticosteroid injections were performed prior to ablation. Mean pre-injection Visual Analogue Scale pain score (VAS) was 8.3, with post-injection VAS score of 4.4 at 24 h and 4.5 at 2 weeks. Mean pre-CRF lesioning VAS pain score was 7.7 with post-CRF lesioning VAS score of 4.4 at 24 h and 4.5 at 2 weeks. CONCLUSIONS: Ultrasound-guided CRF lesioning of the suprascapular nerve in the spinoglenoid notch is a safe treatment for chronic osteoarthritic shoulder pain, with repeat treatments infrequently required. It is associated with significant improvement in VAS pain scores. KEY POINTS: • Ultrasound-guided continuous radiofrequency lesioning of the suprascapular nerve in the spinoglenoid notch is a safe treatment for chronic shoulder pain in degenerative disease, with repeat treatments infrequently required. • The procedure is performed under ultrasound guidance, without the use of ionising radiation.


Subject(s)
Catheter Ablation , Osteoarthritis , Humans , Osteoarthritis/complications , Osteoarthritis/surgery , Retrospective Studies , Shoulder Pain/etiology , Shoulder Pain/therapy , Treatment Outcome , Ultrasonography , Ultrasonography, Interventional/methods
12.
Sensors (Basel) ; 22(5)2022 Mar 03.
Article in English | MEDLINE | ID: mdl-35271127

ABSTRACT

Near-infrared (800-2500 nm; NIR) spectroscopy coupled to hyperspectral imaging (NIR-HSI) has greatly enhanced its capability and thus widened its application and use across various industries. This non-destructive technique that is sensitive to both physical and chemical attributes of virtually any material can be used for both qualitative and quantitative analyses. This review describes the advancement of NIR to NIR-HSI in agricultural applications with a focus on seed quality features for agronomically important seeds. NIR-HSI seed phenotyping, describing sample sizes used for building high-accuracy calibration and prediction models for full or selected wavelengths of the NIR region, is explored. The molecular interpretation of absorbance bands in the NIR region is difficult; hence, this review offers important NIR absorbance band assignments that have been reported in literature. Opportunities for NIR-HSI seed phenotyping in forage grass seed are described and a step-by-step data-acquisition and analysis pipeline for the determination of seed quality in perennial ryegrass seeds is also presented.


Subject(s)
Hyperspectral Imaging , Spectroscopy, Near-Infrared , Calibration , Seeds/chemistry , Spectroscopy, Near-Infrared/methods
13.
Metabolites ; 12(1)2022 Jan 04.
Article in English | MEDLINE | ID: mdl-35050159

ABSTRACT

Epichloë endophytes, fungal endosymbionts of Pooidae grasses, are commonly utilized in forage and turf industries because they produce beneficial metabolites that enhance resistance against environmental stressors such as insect feeding and disease caused by phytopathogen infection. In pastoral agriculture, phytopathogenic diseases impact both pasture quality and animal production. Recently, bioactive endophyte strains have been reported to secrete compounds that significantly inhibit the growth of phytopathogenic fungi in vitro. A screen of previously described Epichloë-produced antifeedant and toxic alkaloids determined that the antifungal bioactivity observed is not due to the production of these known metabolites, and so there is a need for methods to identify new bioactive metabolites. The process described here is applicable more generally for the identification of antifungals in new endophytes. This study aims to characterize the fungicidal potential of novel, 'animal friendly' Epichloë endophyte strains NEA12 and NEA23 that exhibit strong antifungal activity using an in vitro assay. Bioassay-guided fractionation, followed by metabolite analysis, identified 61 metabolites that, either singly or in combination, are responsible for the observed bioactivity. Analysis of the perennial ryegrass-endophyte symbiota confirmed that NEA12 and NEA23 produce the prospective antifungal metabolites in symbiotic association and thus are candidates for compounds that promote disease resistance in planta. The "known unknown" suite of antifungal metabolites identified in this study are potential biomarkers for the selection of strains that enhance pasture and turf production through better disease control.

14.
Audiol Neurootol ; 27(3): 235-242, 2022.
Article in English | MEDLINE | ID: mdl-35038700

ABSTRACT

INTRODUCTION: Only a small percentage (6-10%) of patients who are candidates receive cochlear implants (CIs). One potential reason contributing to low usage rates may be confusion regarding which patients to refer for CI evaluation. The extent to which information provided by standard clinical audiologic assessments is sufficient for selecting appropriate CI evaluation referrals is uncertain. The objective of this study is to evaluate the capacity of standard clinical audiologic measures to differentiate CI candidates from noncandidates. METHOD: The study design is a retrospective review of a prospectively maintained CI database from a university-based tertiary medical center of 518 patients undergoing CI evaluations from 2012 to 2020. Each ear of each patient was treated as an independent value. Receiver operating characteristic (ROCs) curves were constructed using aided AzBio sentence recognition scores in quiet and aided AzBio +10 dB signal-to-noise ratio scores <60% as binary classifiers for CI candidacy. For each ROC, we examined the capacity of multiple pure-tone thresholds, pure-tone average (PTA), and CNC word recognition scores (WRSs) measured under earphones to determine CI candidacy. Area under the curve ROC (AUC-ROC) values were calculated to demonstrate the capacity of each model to differentiate CI candidates from noncandidates. RESULTS: Variables with the greatest capacity to accurately differentiate CI candidates from noncandidates using aided AzBio in quiet scores were earphone CNC WRS, earphone pure-tone threshold at 1,000 Hz, and earphone PTA (AUC-ROC values = 0.86-0.88). Using aided AzBio +10 scores as the measure for candidacy, only CNC word recognition had a fair capacity to identify candidates (AUC-ROC value = 0.73). Based on the ROCs, a 1,000 Hz pure-tone threshold >50 dB HL, PTA >57 dB HL, and a monosyllabic WRS <60% can each serve as individual indicators for referral for CI evaluations. CONCLUSION: The current study provides initial indicators for referral and a first step at developing evidence-based criteria for CI evaluation referral using standard audiologic assessments.


Subject(s)
Cochlear Implantation , Cochlear Implants , Speech Perception , Humans , Recognition, Psychology , Retrospective Studies
15.
Otol Neurotol ; 43(2): e165-e173, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34772887

ABSTRACT

OBJECTIVE: Assess associations between postcochlear implant (CI) auditory training and early outcomes related to speech recognition and CI quality of life (CIQOL). STUDY DESIGN: Longitudinal, prospective cohort. SETTING: Tertiary academic center. PATIENTS: Seventy-two adults undergoing cochlear implantation for bilateral severe-to-profound hearing loss. INTERVENTIONS: Self-reported use of three categories of auditory training post-CI activation: (1) face-to-face training (e.g., speech pathologist), (2) passive home-based training (e.g., listening to audiobooks), and (3) computer-based training (e.g., interactive software). MAIN OUTCOME MEASURES: Change in Consonant-Nucleus-Consonant phoneme (CNCp), CNC word (CNCw), AzBio sentences in quiet, and CIQOL-35 Profile global and domain scores from pre-CI to 3-month post-CI. RESULTS: Of 72 patients, 52 (72.2%) used an auditory training resource. Of all patients, 18.4% used face-to-face training, 58.3% passive home-based training, and 33.3% computer-based training. At 3 months post-CI, use of any training was associated with greater improvement in speech recognition (d-range = 0.57-0.85) and global and domain-specific CIQOL scores, except entertainment (d-range = -0.33 to 0.77). Use of computer-based training demonstrated the greatest effect, with larger improvements in speech recognition (CNCp: d = 0.69[0.03,1.35]; CNCw: d = 0.80[0.14,1.46]; AzBio: d = 1.11[0.44,1.77]) and global and all domain-specific CIQOL scores (d-range = 0.05-1.35). Controlling for age, sex, household income, and use of multiple training resources, computer-based training remained the strongest positive predictor of speech recognition and CIQOL improvement, with significant associations with CNCp (ß = 33.07[1,43,64.719]), AzBio (ß = 33.03[5.71,60.35]), and CIQOL-global (ß = 10.92[1.15,20.70]) score improvement. CONCLUSIONS: Our findings provide preliminary evidence-based recommendations for use of specific auditory training resources for new adult CI recipients. Auditory training, especially self-directed computer software, resulted in improved speech recognition and CIQOL outcomes after 3 months and are widely available for CI users.


Subject(s)
Cochlear Implantation , Cochlear Implants , Speech Perception , Adult , Cochlear Implantation/methods , Humans , Prospective Studies , Quality of Life , Treatment Outcome
17.
Molecules ; 26(24)2021 Dec 14.
Article in English | MEDLINE | ID: mdl-34946660

ABSTRACT

Current methods for measuring the abundance of proteogenic amino acids in plants require derivatisation, extended run times, very sensitive pH adjustments of the protein hydrolysates, and the use of buffers in the chromatographic phases. Here, we describe a fast liquid chromatography-mass spectrometry (LC-MS) method for the determination of amino acids that requires only three steps: hydrolysis, neutralisation, and sample dilution with a borate buffer solution for pH and retention time stability. The method shows excellent repeatability (repeated consecutive injections) and reproducibility (repeated hydrolysis) in the amino acid content, peak area, and retention time for all the standard amino acids. The chromatographic run time is 20 min with a reproducibility and repeatability of <1% for the retention time and <11% for the peak area of the BSA and quality control (QC) lentil samples. The reproducibility of the total protein levels in the hydrolysis batches 1-4 was <12% for the BSA and the lentil samples. The level of detection on column was below 0.1 µM for most amino acids (mean 0.017 µM).


Subject(s)
Amino Acids/analysis , Lens Plant/chemistry , Plant Proteins/chemistry , Serum Albumin, Bovine/chemistry , Amino Acids/chemistry , Animals , Cattle , Chromatography, High Pressure Liquid , Tandem Mass Spectrometry
18.
Plants (Basel) ; 10(11)2021 Nov 17.
Article in English | MEDLINE | ID: mdl-34834850

ABSTRACT

Asexual Epichloë sp. endophytes in association with pasture grasses produce agronomically important alkaloids (e.g., lolitrem B, epoxy-janthitrems, ergovaline, peramine, and lolines) that exhibit toxicity to grazing mammals and/or insect pests. Novel strains are primarily characterised for the presence of these compounds to ensure they are beneficial in an agronomical setting. Previous work identified endophyte strains that exhibit enhanced antifungal activity, which have the potential to improve pasture and turf quality as well as animal welfare through phytopathogen disease control. The contribution of endophyte-derived alkaloids to improving pasture and turf grass disease resistance has not been closely examined. To assess antifungal bioactivity, nine Epichloë related compounds, namely peramine hemisulfate, n-formylloline-d3, n-acetylloline hydrochloride, lolitrem B, janthitrem A, paxilline, terpendole E, terpendole C, and ergovaline, and four Claviceps purpurea ergot alkaloids, namely ergotamine, ergocornine, ergocryptine, and ergotaminine, were tested at concentrations higher than observed in planta in glasshouse and field settings using in vitro agar well diffusion assays against three common pasture and turf phytopathogens, namely Ceratobasidium sp., Drechslera sp., and Fusarium sp. Visual characterisation of bioactivity using pathogen growth area, mycelial density, and direction of growth indicated no inhibition of pathogen growth. This was confirmed by statistical analysis. The compounds responsible for antifungal bioactivity of Epichloë endophytes hence remain unknown and require further investigation.

19.
Environ Monit Assess ; 193(12): 822, 2021 Nov 18.
Article in English | MEDLINE | ID: mdl-34792660

ABSTRACT

A comprehensive measurement of concentrations of the natural radionuclides 238U, 232Th and 40K, and 226Ra in the soil and rocks along with natural uranium and tritium activity levels in lake water were carried out during the Indian expedition to Antarctica. The samples were collected from the Larsemann Hills region in Antarctica (latitude 69°20' S to 69°25'S, longitude 76°6' E to 76°23'E). The data on the natural radioactivity for this region is limited. The study was carried out to establish baseline levels of radioactivity in different terrestrial matrices of this region such as soil, rocks, and lake water. A radiation survey mapping for terrestrial radioactivity was conducted in the region before collection of soil and rock samples. The soil and rock samples were analyzed for natural radioactivity concentrations using high-resolution gamma spectroscopy system. The major contributor to elevated gamma radiation background is attributed to the higher concentration of 232Th and 40K radionuclides in both soil and rocks. Terrestrial components of gamma dose rate due to natural radioactivity have been estimated from the measured radioactivity concentrations and dose conversion coefficients. Several "hotspots" and high background areas in the region have been identified having significantly higher concentration of 232Th and 40K. Rocks in Larsemann Hills region showed high reserve of thorium mineralization in monazites and 40K in K-feldspar. The concentrations of 232Th in soil are found to be in the range of 106-603 Bq/kg, whereas in rock it is in the range of 8-4514 Bq/kg. Natural radioactivity U (nat) and 3H contents in the lake water samples in Larsemann Hills region were estimated as 0.4 and 1.3 Bq/L and are well within the prescribed limit of radioactivity in drinking water as recommended by World Health Organization.


Subject(s)
Radiation Monitoring , Radioactivity , Soil Pollutants, Radioactive , Antarctic Regions , Background Radiation , Lakes/analysis , Potassium Radioisotopes/analysis , Soil , Soil Pollutants, Radioactive/analysis , Spectrometry, Gamma , Thorium/analysis
20.
Sci Rep ; 11(1): 19542, 2021 10 01.
Article in English | MEDLINE | ID: mdl-34599239

ABSTRACT

The ergot alkaloid ergotamine is produced by Claviceps purpurea, a parasitic fungus that commonly infects crops and pastures of high agricultural and economic importance. In humans and livestock, symptoms of ergotism include necrosis and gangrene, high blood pressure, heart rate, thermoregulatory dysfunction and hallucinations. However, ergotamine is also used in pharmaceutical applications to treat migraines and stop post-partum hemorrhage. To define its effects, metabolomic profiling of the brain was undertaken to determine pathways perturbed by ergotamine treatment. Metabolomic profiling identified the brainstem and cerebral cortex as regions with greatest variation. In the brainstem, dysregulation of the neurotransmitter epinephrine, and the psychoactive compound 2-arachidonylglycerol was identified. In the cerebral cortex, energy related metabolites isobutyryl-L-carnitine and S-3-oxodecanoyl cysteamine were affected and concentrations of adenylosuccinate, a metabolite associated with mental retardation, were higher. This study demonstrates, for the first time, key metabolomic pathways involved in the behavioural and physiological dysfunction of ergot alkaloid intoxicated animals.


Subject(s)
Central Nervous System/drug effects , Central Nervous System/metabolism , Ergotamine/pharmacology , Metabolome , Metabolomics , Serotonin Receptor Agonists/pharmacology , Animals , Area Under Curve , Computational Biology , Ergotamine/chemistry , Metabolomics/methods , Mice , Molecular Structure , ROC Curve , Serotonin Receptor Agonists/chemistry
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