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1.
Plant Cell Environ ; 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101480

RESUMO

Increased atmospheric nitrogen (N) deposition significantly disturbs ecosystem N cycle. Although foliar interception and uptake of N deposition can provide an important alternative N supply to forest ecosystems, the mechanisms regulating foliar N uptake from wet deposition are not fully understood. Here, we selected 19 woody species with a wide range of plant traits from different functional groups and conducted a 15N isotope labelling experiment through brushing 15NH4 + and 15NO3 - solution on canopy leaves. Our findings demonstrate that leaves can directly absorb N from wet deposition within a few hours. The average leaf 15N recoveries were 10% and 28% under 15NH4 + and 15NO3 - treatments across species, respectively, while twig N recoveries were only 1%-7% of leaf N recoveries. Differences in foliar N uptake efficiency among species were closely associated with leaf traits but were little influenced by meteorological conditions or soil nutrient status. Specifically, plants with higher leaf N concentration, larger specific leaf area and lower wax concentration exhibited higher leaf N recovery. Our results indicated that tree canopies could directly absorb N from atmospheric deposition. We highlight the critical role of leaf traits in determining canopy foliar N uptake, which may consequently influence plant competition under elevated N deposition.

2.
Sci Rep ; 14(1): 18106, 2024 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103427

RESUMO

Hypothalamus is a crucial deep brain area that is responsible for the integration and coordination of various brain functions. The altered perfusion of hypothalamus during headache caused by medication-overuse headache (MOH) was previously unknown. In the current study, the altered perfusion of hypothalamic subregions in MOH patients was investigated using state-of-the-art 3D pseudo-continuous arterial spin labeling (PCASL) MR imaging. In this study, 29 normal controls subjects (NCs) and 29 MOH patients underwent 3D PCASL and brain structural MR imaging. The hypothalamus was automatically segmented into 10 subunits and the volume of each subunit was automatically determined using Freesurfer software (v7.4.1). All segmented hypothalamic subunits were converted to individual hypothalamic subunit masks. The cerebral blood flow (CBF) images were coregistered with the raw brain structural images and resliced. The CBF value of each hypothalamic subunit was extracted from the warped CBF images. The volume and CBF value of each hypothalamic subunit were analyzed using the independent sample T test and Mann-Whitney U test, receiver operating characteristic (ROC) curve analysis, and Pearson and Spearman correlation analysis. Hypothalamic subunits with significantly decreased perfusion were located in the left posterior, left tubular superior, right anterior-inferior, right tubular inferior, right tubular superior, right posterior subunit and the entire right hypothalamus [CBF value for MOH vs NC (mL/100 g·min): 48.41 ± 6.75 vs 54.08 ± 11.47, 44.44 ± 4.79 vs 48.11 ± 7.73, 41.49 (32.90, 61.46) vs 49.38 ± 10.47, 46.62 ± 7.04 vs 53.90 ± 11.75, 42.12 ± 5.74 vs 47.02 ± 9.99, 42.79 ± 5.15 vs 47.93 ± 10.48 and 43.58 ± 5.06 vs 48.65 ± 9.33, respectively] in MOH compared to NC (P < 0.05). ROC analysis for these positive subunits revealed that area under the curve was 0.658-0.693, and ROC curve for left posterior subunit had the highest specificity of 93.10% while the entire right hypothalamus had the highest sensitivity of 72.41%. Further correlation analysis showed that the CBF value of the left posterior, right anterior-inferior, right tubular superior, whole right hypothalamus presented significantly negative correlation with Hamilton Depression Scale (HAMD) score (P < 0.05). Hypoperfusion of hypothalamic subunits may contribute to the understanding of MOH pathogenesis, and the 3D PCASL could be considered as a potential diagnostic and assessment tool for MOH.


Assuntos
Circulação Cerebrovascular , Hipotálamo , Imageamento por Ressonância Magnética , Humanos , Hipotálamo/diagnóstico por imagem , Hipotálamo/metabolismo , Masculino , Feminino , Imageamento por Ressonância Magnética/métodos , Adulto , Pessoa de Meia-Idade , Transtornos da Cefaleia Secundários/diagnóstico por imagem , Transtornos da Cefaleia Secundários/fisiopatologia , Imageamento Tridimensional , Marcadores de Spin , Estudos de Casos e Controles , Curva ROC
3.
Data Brief ; 55: 110762, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39149715

RESUMO

By means of a unique, low vibration circular conveyor system, plant sensors capturing light detection and ranging (LiDAR) unit and thermal camera were moved on the same route, around blocks of apple trees, with seven Malus x domestica Borkh. 'Gala' apple trees in each block. Measurements took place four times during the season. Additionally at harvest, diurnal courses were recorded with 18 readings during three days. The data are provided as [i] raw data (3D point clouds of 3 blocks of trees scanned from right and left sides and thermal images), [ii] processed 3D point clouds of canopies annotated with temperature data from the thermal camera, and [iii] manually segmented 3D point clouds of fruit, representing the spatially-resolved fruit surface temperature (FST). Manual FST readings are provided on each measuring date and during diurnal courses. The fruit data are capturing 1236 FST, providing temperature distribution as 3D point cloud and one manually recorded reference FST per fruit. Additionally, fruit size and colour were measured for each fruit, despite for the first date, when fruit were too small for colour readings. Weather data are provided from a station located in the orchard. Usage of data could be (a) in developing methodology for 3D point cloud processing based on raw data, accomplished with reference FST data. Furthermore, (b) the pre-processed point clouds of fruit surface temperature can be reused in ecophysiological studies related to global warming, optimizing fruit production systems, and other. Because the sensors and trees were measured from the same angle and distance, time series analysis of the canopies would be possible.

4.
Biochim Biophys Acta Mol Cell Res ; : 119815, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39151475

RESUMO

The Ku heterodimer (Ku70/Ku80) is central to the non-homologous end-joining (NHEJ) pathway. Ku binds to the broken DNA ends and promotes the assembly of the DNA repair complex. The N-terminal Ku70 von Willebrand A (vWA) domain is known to mediate protein-protein interactions important for the repair process. In particular, the D192 and D195 residues within helix 5 of the Ku70 vWA domain were shown to be essential for NHEJ function, although the precise role of these residues was not identified. Here, we set up a miniTurbo screening system to identify Ku70 D192/D195 residue-specific interactors in a conditional, human Ku70-knockout cell line in response to DNA damage. Using fusion protein constructs of Ku70 wild-type and mutant (D192A/D195R) with miniTurbo, we identified a number of candidate proximal interactors in response to DNA damage treatment, including DNA Ligase IV (LigIV), a known and essential NHEJ complex member. Interestingly, LigIV was enriched in our wildtype screen but not the Ku70 D192A/D195R screen, suggesting its interaction is disrupted by the mutation. Validation experiments demonstrated that the DNA damage-induced interaction between Ku70 and LigIV was disrupted by the Ku70 D192A/D195R mutations. Our findings provide greater detail about the interaction surface between the Ku70 vWA domain and LigIV and offer strong evidence that the D192 and D195 residues are important for NHEJ completion through an interaction with LigIV. Altogether, this work reveals novel potential proximal interactors of Ku in response to DNA damage and identifies Ku70 D192/D195 residues as essential for LigIV interaction with Ku during NHEJ.

5.
BMC Nutr ; 10(1): 110, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39138549

RESUMO

BACKGROUND: On 6 April 2022, legislation came into effect in England requiring calorie labels to be applied to food items on menus of larger food businesses. This study aimed to assess the impact of calorie labelling on (a) food purchased and (b) energy content of menu options in worksite cafeterias. METHODS: Product-level sales data and energy content of available items was obtained from 142 worksite cafeterias from January 2022-October 2022. Interrupted-time-series (ITS) analysis with level and slope change evaluated daily energy (kcal) purchased per item, and ITS with level change assessed mean energy per option available on menus before and after calorie labelling. Each analysis was conducted 6 weeks and 6 months from implementation. A post-hoc ITS examined weekly energy purchased per item over a longer period (March 2021-October 2022; 135 sites). RESULTS: There was no evidence calorie labelling changed the energy content of foods purchased (6-week: + 0.60 cal/product, 95%CI:-2.54, + 3.75; 6-month: + 1.59 cal/product, 95%CI:-0.96, + 4.16). Post-hoc analyses suggested calorie labels were associated with a reduction in mean energy of items purchased over time (-0.65 kcal/week, 95%CI:-0.81,-0.49), but a significant increase (+ 3 kcal, 95%CI: + 0.43, + 5.60) at the point of implementation. There was a reduction in the mean energy content of menu options at each seasonal menu change (April 2022:-1.79 kcal, 95%CI:-3.42,-0.15; July 2022:-4.18 kcal, 95% CI:-7.65,-0.73). CONCLUSION: This large observational study in worksite cafeterias found no evidence to indicate the introduction of calorie labelling led to any immediate reduction in energy purchased by customers. There was some evidence of increasing impact over time, possibly associated with changes in menu offerings, but this effect was small and cannot be directly attributed to calorie labelling.

6.
Plant Physiol Biochem ; 215: 109025, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39142014

RESUMO

Hemicellulose is key in determining the fate of plant cell wall in almost all growth and developmental stages. Nevertheless, there is limited knowledge regarding its involvement in the development and ripening of banana fruit. This study investigated changes in the temporal-spatial distribution of various hemicellulose components, hemicellulose content, activities of the main hydrolysis enzymes, and transcription level of the main hemicellulose-related gene families in banana peels. Both hemicellulose and xylan contents were positively correlated to the fruit firmness observed in our previous study. On the contrary, the xylanase activity was negatively correlated to xylan content and the fruit firmness. The vascular bundle cells, phloem, and cortex of bananas are abundant in xyloglucan, xylan, and mannan contents. Interestingly, the changes in the signal intensity of the CCRC-M104 antibody recognizing non-XXXG type xyloglucan are positively correlated to hemicellulose content. According to RNA-Seq analysis, xyloglucan and xylan-related genes were highly active in the early stages of growth, and the expression of MaMANs and MaXYNs increased as the fruit ripened. The abundance of plant hormonal and growth-responsive cis-acting elements was detected in the 2 kb upstream region of hemicellulose-related gene families. Interaction between hemicellulose and cell wall-specific proteins and MaKCBP1/2, MaCKG1, and MaHKL1 was found. The findings shed light on cell wall hemicellulose's role in banana fruit development and ripening, which could improve nutrition, flavor, and reduce postharvest fruit losses.

7.
Quant Imaging Med Surg ; 14(8): 5665-5681, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39144048

RESUMO

Background: Preoperative grading gliomas is essential for therapeutic clinical decision-making. Current non-invasive imaging modality for glioma grading were primarily focused on magnetic resonance imaging (MRI) or positron emission tomography (PET) of the tumor region. However, these methods overlook the peritumoral region (PTR) of tumor and cannot take full advantage of the biological information derived from hybrid-imaging. Therefore, we aimed to combine multiparameter from hybrid 18F-fluorodeoxyglucose (18F-FDG) PET/MRI of the solid component and PTR were combined for differentiating high-grade glioma (HGG) from low-grade glioma (LGG). Methods: A total of 76 patients with pathologically confirmed glioma (41 HGG and 35 LGG) who underwent simultaneous 18F-FDG PET, arterial spin labelling (ASL), and diffusion-weighted imaging (DWI) with hybrid PET/MRI were retrospectively enrolled. The relative maximum standardized uptake value (rSUVmax), relative cerebral blood flow (rCBF), and relative minimum apparent diffusion coefficient (rADCmin) for the solid component and PTR at different distances outside tumoral border were compared. Receiver operating characteristic (ROC) curves were applied to assess the grading performance. A nomogram for HGG prediction was constructed. Results: HGGs displayed higher rSUVmax and rCBF but lower rADCmin in the solid component and 5 mm-adjacent PTR, lower rADCmin in 10 mm-adjacent PTR, and higher rCBF in 15- and 20-mm-adjacent PTR. rSUVmax in solid component performed best [area under the curve (AUC) =0.865] as a single parameter for grading. Combination of rSUVmax in the solid component and adjacent 20 mm performed better (AUC =0.881). Integration of all 3 indicators in the solid component and adjacent 20 mm performed the best (AUC =0.928). The nomogram including rSUVmax, rCBF, and rADCmin in the solid component and 5-mm-adjacent PTR predicted HGG with a concordance index (C-index) of 0.906. Conclusions: Multiparametric 18F-FDG PET/MRI from the solid component and PTR performed excellently in differentiating HGGs from LGGs. It can be used as a non-invasive and effective tool for preoperative grade stratification of patients with glioma, and can be considered in clinical practice.

8.
Int J Pharm ; : 124588, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39153644

RESUMO

This study investigates the biodistribution of a nano lipid carrier system (NLCs) containing the hydrophobic drug erlotinib (ERL-NLCs). The system was labelled with the fluorescent dye IR-780 for real-time dynamic imaging. ERL-NLCs were initially developed using the ultrasonication method with oleic acid and stearic acid. In vitro and ex vivo studies were performed to confirm the formation and penetration of NLCs within the intestine. Subsequently, the biological distribution of ERL-NLCs was monitored using a fluorescent dye through the IVIS® fluorescent optical imaging technique in whole live animals. Mice were orally administered blank IR 780 dye solution, ERL suspension, and IR 780 labelled NLCs. Fluorescence images were acquired at different time intervals up to 24 h and then total radiant efficiency was calculated through the region of interest (ROI) of the whole animal at each interval of time for all three groups. To validate the results obtained from in vivo imaging, various organs including lungs, heart, liver, both kidneys, stomach, and intestine were subsequently extracted and examined after 24 h. The ROI was found to be higher in the blank IR 780 dye solution, followed by the drug suspension and IR 780 labelled NLCs. These results confirm that the plain ERL suspension distributes across the body, and its encapsulation in NLCs facilitates passage through the lymphatic intestinal pathway, effectively avoiding first-pass metabolism. The remarkable results indicated that the NLCs formulation effectively circumvents first-pass metabolism by adopting the intestinal lymphatic pathway, thereby enhancing the oral bioavailability of the drug. This observed behaviour underscores the potential of NLCs in optimizing drug delivery and minimizing adverse effects associated with gastrointestinal and metabolic processes.

9.
Am J Clin Pathol ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110465

RESUMO

OBJECTIVES: Laboratory testing, crucial for medical diagnosis, has 3 phases: preanalytical, analytical, and postanalytical. This study set out to demonstrate whether automating tube labeling through artificial intelligence (AI) support enhances efficiency, reduces errors, and improves outpatient phlebotomy services. METHODS: The NESLI tube-labeling robot (Labenko Informatics), which uses AI models for tube selection and handling, was used for the experiments. The study evaluated the NESLI robot's operational performance, including labelling time, technical problems, tube handling success, and critical stock alerts. The robot's label readability was also tested on various laboratory devices. This research will contribute to the field's understanding of the potential impact of automated tube-labeling systems on laboratory processes in the preanalytical phase. RESULTS: NESLI demonstrated high performance in labeling processes, achieving a success rate of 99.2% in labeling parameters and a success rate of 100% in other areas. For nonlabeling parameters, the average labeling time per tube was measured at 8.96 seconds, with a 100% success rate in tube handling and critical stock warnings. Technical issues were promptly resolved, affirming the NESLI robot's effectiveness and reliability in automating the tube-labeling processes. CONCLUSIONS: Robotic systems using AI, such as NESLI, have the potential to increase process efficiency and reduce errors in the preanalytical phase of laboratory testing. Integration of such systems into comprehensive information systems is crucial for optimizing phlebotomy services and ensuring timely and accurate diagnostics.

10.
Sci Total Environ ; 951: 175409, 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39142402

RESUMO

The significance of sulphur (S) availability for crop yield and quality is highlighted under the global S deficiency scenario. However, little is known about the temporal trend in belowground organic S mineralisation when restoring land to productive agricultural systems, particularly for the deeper soil parts. Therefore, we investigated the decomposition of 35S-labelled methionine in surface (0-30 cm) and subsurface soil (30-60 cm and 60-90 cm) over a 48-year recultivation chronosequence (sampled after1, 8, 14, 24 and 48 years). Soil total sulphur (TS) significantly (p < 0.05) increased in surface soil but not in subsurface soils after 48 years of recultivation. Overall, the immobilisation of 35S-methionine (35S-MB) in subsurface soils relative to year 1 significantly decreased over the chronosequence but did not change in the surface samples. The 35S-MB values in subsurface soils were positively corrected with soil carbon (C) stoichiometry (Pearson correlation, p < 0.05), suggesting the immobilisation of methionine was likely constrained by microbial C demand in deep soil. Compared to year 1, 35S-SO42- released from 35S-methionine significantly declined throughout the older (≥ 8 years) soil profiles. Significant (p < 0.05) changes in the organic 35S partition (35S immobilisation and 35S released as sulphate) were observed in year 8 after the soil was recultivated with N-fixing alfalfa or fertilisers. Whereas, after that (≥ 14 years), soil organic S partition remained affected when conventional tillage and agricultural crops dominated this site. Indicating that the effect of recultivation on organic S decomposition depends on the manner of recultivation management. Our study contributes to an improved understanding of amino acid S and organic S mineralisation under severe anthropogenic disturbance.

12.
Appl Radiat Isot ; 212: 111460, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39094205

RESUMO

Radiolabelled autologous leukocytes have been used for the clinical diagnosis of inflammation and infection. To develop a stable and efficient radiopharmaceutical for labelling leukocytes, we prepared a novel radioiodinated cell-penetrating peptide, 125I-TAT, using a bi-functional linker. 125I-TAT was stable for two days under three different temperature conditions of -20 °C, 4 °C, and 40 °C, with its radiochemical purity remaining over 99%. Iodinated TAT was non-toxic to leukocytes with an IC50 value of over 100 µM. The labelling efficiency of 125I-TAT using 1x107 cells ranged from 27% to 53% when the three leukocyte cell lines were pre-treated with DMSO. This is comparable to the labelling efficiency recommended by the guideline for conventional labelling agents using 2x108 cells. Radioiodinated cell-penetrating peptide may be an improved radiopharmaceutical for white blood cell scans by further optimization.

13.
Radiol Case Rep ; 19(10): 4163-4166, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39101019

RESUMO

A 62-year-old woman showed an elevation of carcinoembryonic antigen (CEA) level 15 years after the left breast cancer, i.e., tubule forming type luminal micro invasive cancer, operation. Positron emission tomography/computed tomography (PET/CT) showed avid radio-tracer uptake in her right axillary and supraclavicular lymph nodes. Mammography, ultrasound (US), PET/CT, and magnetic resonance imaging showed no abnormalities in her right breast. US of the enlarged lymph nodes showed very low internal echoes. Pathological study using a core needle biopsy specimen of a right axillary node showed human epidermal growth factor receptor type 2 (HER2) positive atypical cells growing in solid and trabecular fashions. Under the presumed diagnosis of right occult breast cancer, the patient received anti-HER2 agents-containing chemotherapy, leading to marked shrinkage of the enlarged lymph nodes with normalization of the elevated CEA level. To confirm the pathological efficacy, sentinel plus sampling node biopsy was done to the patient. Postoperative pathological study of the resected nodes showed fibrosis and no viable cancer cells. The patient further received radiotherapy both to the right breast and suprarclavicular region followed by adjuvant anti-HER2 agents therapy, and has been well without any recurrences for 39 months. Diagnostic physicians should note that metastatic lymph nodes of occult breast cancer show very low internal echoes.

14.
Trials ; 25(1): 441, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38956594

RESUMO

BACKGROUND: Major depressive disorder (MDD) is a leading cause of disability worldwide across domains of health and cognition, affecting overall quality of life. Approximately one third of individuals with depression do not fully respond to treatments (e.g., conventional antidepressants, psychotherapy) and alternative strategies are needed. Recent early phase trials suggest psilocybin may be a safe and efficacious intervention with rapid-acting antidepressant properties. Psilocybin is thought to exert therapeutic benefits by altering brain network connectivity and inducing neuroplastic changes that endure for weeks post-treatment. Although early clinical results are encouraging, psilocybin's acute neurobiological effects on neuroplasticity have not been fully investigated. We aim to examine for the first time how psilocybin acutely (intraday) and subacutely (weeks) alters functional brain networks implicated in depression. METHODS: Fifty participants diagnosed with MDD or persistent depressive disorder (PDD) will be recruited from a tertiary mood disorders clinic and undergo 1:1 randomization into either an experimental or control arm. Participants will be given either 25 mg psilocybin or 25 mg microcrystalline cellulose (MCC) placebo for the first treatment. Three weeks later, those in the control arm will transition to receiving 25 mg psilocybin. We will investigate whether treatments are associated with changes in arterial spin labelling and blood oxygenation level-dependent contrast neuroimaging assessments at acute and subacute timepoints. Primary outcomes include testing whether psilocybin demonstrates acute changes in (1) cerebral blood flow and (2) functional brain activity in networks associated with mood regulation and depression when compared to placebo, along with changes in MADRS score over time compared to placebo. Secondary outcomes include changes across complementary clinical psychiatric, cognitive, and functional scales from baseline to final follow-up. Serum peripheral neurotrophic and inflammatory biomarkers will be collected at baseline and follow-up to examine relationships with clinical response, and neuroimaging measures. DISCUSSION: This study will investigate the acute and additive subacute neuroplastic effects of psilocybin on brain networks affected by depression using advanced serial neuroimaging methods. Results will improve our understanding of psilocybin's antidepressant mechanisms versus placebo response and whether biological measures of brain function can provide early predictors of treatment response. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT06072898. Registered on 6 October 2023.


Assuntos
Afeto , Encéfalo , Transtorno Depressivo Maior , Psilocibina , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Psilocibina/uso terapêutico , Psilocibina/efeitos adversos , Psilocibina/administração & dosagem , Psilocibina/farmacologia , Afeto/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Transtorno Depressivo Maior/tratamento farmacológico , Imageamento por Ressonância Magnética , Fatores de Tempo , Resultado do Tratamento , Adulto , Plasticidade Neuronal/efeitos dos fármacos , Adulto Jovem , Masculino , Antidepressivos/uso terapêutico , Feminino , Pessoa de Meia-Idade
15.
16.
Food Chem ; 459: 140303, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38991452

RESUMO

To identify a novel optimized strategy for preventing fraudulent substitutions of squid species and origins, forty European squids (Loligo vulgaris) and forty flying squids (Todarodes sagittatus) from the Mediterranean Sea and Atlantic Ocean were analyzed for δ13C, δ15N, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, and Lu using isotope ratio mass spectrometry and inductively coupled plasma-mass spectrometry. While δ13C and δ15N variations were mainly species-related, they alone could not reliably distinguish samples. To address this issue, decision rules were developed using Classification and Regression Tree analysis. Threshold values for δ13C (-19.91‰), δ15N (14.87‰), and Pr (0.49 µg kg-1) enabled successful discrimination among Mediterranean European squids, Atlantic European squids, Mediterranean flying squids, and Atlantic flying squids, achieving over 90% accuracy, 81% precision, 80% sensitivity, and 93% specificity. This method holds promise for enhancing traceability and safety in the seafood industry, ensuring product integrity and consumer trust.

17.
Anal Sci Adv ; 5(5-6): e2400007, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38948317

RESUMO

The field of metabolomics has gained tremendous interest in recent years. Whether the goal is to discover biomarkers related to certain pathologies or to better understand the impact of a drug or contaminant, numerous studies have demonstrated how crucial it is to understand variations in metabolism. Detailed knowledge of metabolic variabilities can lead to more effective treatments, as well as faster or less invasive diagnostics. Exploratory approaches are often employed in metabolomics, using relative quantitation to look at perturbations between groups of samples. Most metabolomics studies have been based on metabolite profiling using relative quantitation, with very few studies using an approach for absolute quantitation. Using accurate quantitation facilitates the comparison between different studies, as well as enabling longitudinal studies. In this review, we discuss the most widely used techniques for quantitative metabolomics using mass spectrometry (MS). Various aspects will be addressed, such as the use of external and/or internal standards, derivatization techniques, in vivo isotopic labelling, or quantitative MS imaging. The principles, as well as the associated limitations and challenges, will be described for each approach.

18.
Tob Control ; 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38950911

RESUMO

Health warnings and messages-or health warning labels (HWLs)-are integral to tobacco control efforts, but their sustained impact necessitates regular rotation. This paper explores challenges in HWL rotation implementation across six diverse countries: Chile, Guyana, Indonesia, Jamaica, Mexico, and Vietnam. 19 in-depth interviews were conducted with government officials and representatives from civil society organisations and academia. Interviews explored the effectiveness of HWL regulations, the processes involved in their execution, and any challenges encountered along the way. Interviews were analysed thematically, using a combination of deductive and inductive approaches. Interviews revealed critical challenges that fall into two categories: specific and overarching. Government priorities and transitions, political will, time and bureaucracy, legal loopholes, lack of images, evaluation, and economic and human resources constitute HWL-specific challenges. Broad tobacco control challenges included tobacco industry interference and enforcement difficulties. To address HWL rotation challenges, international bodies such as WHO could establish extensive image banks, pre-evaluated for effectiveness and cultural relevance. In addition, countries must institutionalise the rotation process by establishing mechanisms that avoid having to pass complex legal instruments with each new round of warnings, delegating responsibilities to stable government institutions, addressing legal loopholesand planning for multiple rounds within a single legal instrument. Further, partnerships at national and international levels, along with systematic evaluations, are crucial for successful HWL implementation. These recommendations form a comprehensive framework for global collaboration, aiming to strengthen tobacco prevention through impactful HWLs on a sustainable basis.

19.
EMBO J ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38997504

RESUMO

Cell communication coordinates developmental processes, maintains homeostasis, and contributes to disease. Therefore, understanding the relationship between cells in a shared environment is crucial. Here we introduce Positive Ultra-bright Fluorescent Fusion For Identifying Neighbours (PUFFFIN), a cell neighbour-labelling system based upon secretion and uptake of positively supercharged fluorescent protein s36GFP. We fused s36GFP to mNeonGreen or to a HaloTag, facilitating ultra-bright, sensitive, colour-of-choice labelling. Secretor cells transfer PUFFFIN to neighbours while retaining nuclear mCherry, making identification, isolation, and investigation of live neighbours straightforward. PUFFFIN can be delivered to cells, tissues, or embryos on a customisable single-plasmid construct composed of interchangeable components with the option to incorporate any transgene. This versatility enables the manipulation of cell properties, while simultaneously labelling surrounding cells, in cell culture or in vivo. We use PUFFFIN to ask whether pluripotent cells adjust the pace of differentiation to synchronise with their neighbours during exit from naïve pluripotency. PUFFFIN offers a simple, sensitive, customisable approach to profile non-cell-autonomous responses to natural or induced changes in cell identity or behaviour.

20.
Plant Biol (Stuttg) ; 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39012225

RESUMO

Tamarix ramosissima has an important role in stabilizing sand dunes in desert ecosystems. Understanding the water use strategies of T. ramosissima is essential to understand its adaptations on coppice dunes. We utilized the stable isotopes δ2H and δ18O in soil water, groundwater, and xylem water to identify monthly differences in water sources. Additionally. we explored rooting depth using 2H2O as an artificial tracer. In May, T. ramosissima derived 75% of its water from shallow and middle soil layers. In July, it absorbed 90% water from middle and deep soil layers. In August and September, it acquired approximately 80% of its water from deep soil layers. The labelling using 2H as an artificial tracer indicated that the root system of T. ramosissima could reach depths >500 cm in the coppice dunes. 2H absorption was observed at depths of 100, 200, 300 and 400 cm. Soil water is the dominant water source for T. ramosissima in the coppice dunes because groundwater is at depths >30 m. The flexible water-use strategies of T. ramosissima enable it to effectively utilize different available water sources to adapt to the arid environment. These findings improve our understanding of water uptake patterns and drought adaptation strategies of T. ramosissima in the coppice dunes of desert ecosystems.

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