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1.
Plant Cell Rep ; 43(10): 250, 2024 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-39361041

RESUMEN

KEY MESSAGE: Analysis of the N-terminome of Physcomitrella reveals N-terminal monomethylation of nuclear-encoded, mitochondria-localized proteins. Post- or co-translational N-terminal modifications of proteins influence their half-life as well as mediating protein sorting to organelles via cleavable N-terminal sequences that are recognized by the respective translocation machinery. Here, we provide an overview on the current modification state of the N-termini of over 4500 proteins from the model moss Physcomitrella (Physcomitrium patens) using a compilation of 24 N-terminomics datasets. Our data reveal distinct proteoforms and modification states and confirm predicted targeting peptide cleavage sites of 1,144 proteins localized to plastids and the thylakoid lumen, to mitochondria, and to the secretory pathway. In addition, we uncover extended N-terminal methylation of mitochondrial proteins. Moreover, we identified PpNTM1 (P. patens alpha N-terminal protein methyltransferase 1) as a candidate for protein methylation in plastids, mitochondria, and the cytosol. These data can now be used to optimize computational targeting predictors, for customized protein fusions and their targeted localization in biotechnology, and offer novel insights into potential dual targeting of proteins.


Asunto(s)
Bryopsida , Mitocondrias , Proteínas de Plantas , Plastidios , Bryopsida/metabolismo , Bryopsida/genética , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Metilación , Plastidios/metabolismo , Mitocondrias/metabolismo , Procesamiento Proteico-Postraduccional , Proteómica/métodos , Transporte de Proteínas , Orgánulos/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética
2.
Artículo en Inglés | MEDLINE | ID: mdl-39228178

RESUMEN

BACKGROUND: Women have a higher prevalence of tricuspid regurgitation (TR) and present at more advanced stages as compared with men. Given the high operative mortality associated with tricuspid valve (TV) surgery, transcatheter tricuspid valve interventions (TTVI) have emerged as a promising treatment option. We explored sex-based differences among patients with significant TR who would be expected to be eligible for TTVI. METHODS: Between March 2021-2022, 12,677 unique adult patients underwent a transthoracic echocardiogram at our tertiary care institution. Clinical and echocardiographic data were collected for patients with more than moderate TR. The 2021 European Society of Cardiology valve guidelines were used to retrospectively define sub-populations who would have been eligible for TTVI, TV surgery, or medical therapy. Patients were grouped by sex and compared using t-tests, Wilcoxon rank-sum, Pearson chi-square, and Cox regression for survival analysis. RESULTS: Of 569 patients, 52% (296/569) were female. Men had a higher prevalence of left ventricular dysfunction (p < 0.001), mitral regurgitation (p = 0.023), and signs of heart failure (New York Heart Association stage III (p = 0.031)). Women had more isolated TR (p = 0.020) and TR due to severe pulmonary hypertension (p < 0.001). Most patients (74.6% of women, 76.9% of men) were precluded from both transcatheter and surgical intervention due to advanced disease. 10.8% of women and 9.2% of men would have qualified for TTVI (p = 0.511). CONCLUSION: The majority of patients with significant TR presenting to a tertiary care center are not eligible for TTVI. Sex is not a predictor of eligibility for TTVI among patients with significant TR.

3.
Strahlenther Onkol ; 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39222095

RESUMEN

PURPOSE: This study compares the objective American Society of Anesthesiologists (ASA) and Adult Comorbidity Evaluation-27 (ACE-27) scores with the subjective Eastern Cooperative Oncology Group performance status (ECOG PS) for patient outcome prediction. METHODS: We retrospectively analyzed head and neck squamous cell carcinoma patients treated with adjuvant (chemo)radiotherapy at the LMU Munich from June 2008 to June 2015. The study focused on associations between patient outcomes; treatment failures; known risk factors (including human papillomavirus [HPV] status and tumor stage); and the comorbidity indices ECOG-PS, ASA score, and ACE-27. The Kaplan-Meier method and Cox proportional hazards model were used for survival analysis and identifying independent risk factors. RESULTS: A total of 302 patients were analyzed, 175 received concurrent chemotherapy. Median follow-up was 61.8 months, and median age at diagnosis was 61 years. The 3­ and 5­year overall survival (OS) and disease-free survival (DFS) rates were 70.5%/60.2% and 64.7%/57.6%, respectively. Both ACE-27 and ASA showed significant correlations with OS in univariate and multivariate analyses, while ECOG-PS was significant only in univariate analysis. ASA and ACE-27 scores were also significantly correlated with local and locoregional recurrence, but only HPV status and tumor stage were significant in multivariate models. CONCLUSION: ACE-27 and ASA score effectively categorize patients' risks in adjuvant radiotherapy for head and neck cancer, proving more predictive of overall survival than ECOG-PS. These results underscore the importance of objective comorbidity assessment and suggest further prospective studies.

4.
Forensic Sci Int Genet ; 74: 103129, 2024 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-39243526

RESUMEN

The identification of body fluids is an important area of forensic genetics. In particular, the susceptibility to degradation of casework samples is of crucial importance, as the traces can often be exposed to different environmental conditions over a long period of time. RNAs especially are used as molecular markers for the identification of body fluids in forensics. Messenger RNAs (mRNAs) show an increased susceptibility to degradation, e.g. under humidity and UV radiation but are highly body fluid-specific. The shorter micro RNAs (miRNAs), however, are less susceptible to degradation, but only a few body fluid-specific markers could be investigated. In this study, a self-developed mRNA/miRNA multiplex assay for capillary electrophoresis from a preliminary study was further adapted and validated. The approach was applied to casework samples, animal samples, and a storage study. The advantages and disadvantages of the mRNA/miRNA assay were investigated in order to review a possible application for forensic casework. Some miRNA markers were also detected in animal samples, which once again underlines the possible non-specificity of miRNAs. In the storage study, the different markers were detected for different lengths of time depending on the body fluid examined. For almost all body fluids, the miRNA markers were still detectable after a period of 35 days under environmental conditions compared to the mRNA markers. The mRNA peaks were often already clearly reduced or no longer detectable after 14 days. The results show the advantage of the new mRNA/miRNA assay compared to established mRNA approaches, especially for older and degraded samples, but the assay has its limitations due to the limited number of specific miRNA markers.

5.
Respir Physiol Neurobiol ; 328: 104314, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39117159

RESUMEN

Rett syndrome (RTT) is an autism spectrum disorder caused by loss-of-function mutations in the methyl-CPG-binding protein 2 (Mecp2) gene. Frequent apneas and irregular breathing are prevalent in RTT, and also occur in rodent models of the disorder, including Mecp2Bird and Mecp2R168X mice. Sarizotan, a serotonin 5-HT1a and dopamine D2-like receptor agonist, reduces the incidence of apneas and irregular breathing in mouse models of RTT (Abdala et al., 2014). Targeting the 5HT1a receptor alone also improves respiration in RTT mice (Levitt et al., 2013). However, the contribution of D2-like receptors in correcting these respiratory disturbances remains untested. PAOPA, a dopamine D2-like receptor positive allosteric modulator, and quinpirole, a dopamine D2-like receptor orthosteric agonist, were used in conjunction with whole-body plethysmography to evaluate whether activation of D2-like receptors is sufficient to improve breathing disturbances in female heterozygous Mecp2Bird/+ and Mecp2R168X/+ mice. PAOPA did not significantly change apnea incidence or irregularity score in RTT mice. PAOPA also had no effect on the ventilatory response to hypercapnia (7 % CO2). In contrast, quinpirole reduced apnea incidence and irregularity scores and improved the hypercapnic ventilatory response in Mecp2R168X/+ and Mecp2Bird/+ mice, while also reducing respiratory rate. These results suggest that D2-like receptors could contribute to the positive effects of sarizotan in the correction of respiratory abnormalities in Rett syndrome. However, positive allosteric modulation of D2-like receptors alone was not sufficient to evoke these effects.


Asunto(s)
Modelos Animales de Enfermedad , Agonistas de Dopamina , Proteína 2 de Unión a Metil-CpG , Quinpirol , Receptores de Dopamina D2 , Síndrome de Rett , Animales , Síndrome de Rett/tratamiento farmacológico , Síndrome de Rett/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores de Dopamina D2/agonistas , Agonistas de Dopamina/farmacología , Femenino , Ratones , Quinpirol/farmacología , Proteína 2 de Unión a Metil-CpG/genética , Respiración/efectos de los fármacos , Ratones Transgénicos , Regulación Alostérica/efectos de los fármacos , Ratones Endogámicos C57BL
6.
Mol Syst Biol ; 20(10): 1134-1150, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39134886

RESUMEN

Genome-scale metabolic models (GEMs) can facilitate metabolism-focused multi-omics integrative analysis. Since Yeast8, the yeast-GEM of Saccharomyces cerevisiae, published in 2019, has been continuously updated by the community. This has increased the quality and scope of the model, culminating now in Yeast9. To evaluate its predictive performance, we generated 163 condition-specific GEMs constrained by single-cell transcriptomics from osmotic pressure or reference conditions. Comparative flux analysis showed that yeast adapting to high osmotic pressure benefits from upregulating fluxes through central carbon metabolism. Furthermore, combining Yeast9 with proteomics revealed metabolic rewiring underlying its preference for nitrogen sources. Lastly, we created strain-specific GEMs (ssGEMs) constrained by transcriptomics for 1229 mutant strains. Well able to predict the strains' growth rates, fluxomics from those large-scale ssGEMs outperformed transcriptomics in predicting functional categories for all studied genes in machine learning models. Based on those findings we anticipate that Yeast9 will continue to empower systems biology studies of yeast metabolism.


Asunto(s)
Genoma Fúngico , Modelos Biológicos , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/crecimiento & desarrollo , Biología de Sistemas/métodos , Proteómica , Transcriptoma , Redes y Vías Metabólicas/genética , Presión Osmótica , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Carbono/metabolismo , Nitrógeno/metabolismo , Perfilación de la Expresión Génica
7.
Mov Disord ; 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39022835

RESUMEN

BACKGROUND: Preclinical, postmortem, and positron emission tomography (PET) imaging studies have pointed to neuroinflammation as a key pathophysiological hallmark in primary 4-repeat (4R) tauopathies and its role in accelerating disease progression. OBJECTIVE: We tested whether microglial activation (1) progresses in similar spatial patterns as the primary pathology tau spreads across interconnected brain regions, and (2) whether the degree of microglial activation parallels tau pathology spreading. METHODS: We examined in vivo associations between tau aggregation and microglial activation in 31 patients with clinically diagnosed 4R tauopathies, using 18F-PI-2620 PET and 18F-GE180 (translocator protein [TSPO]) PET. We determined tau epicenters, defined as subcortical brain regions with highest tau PET signal, and assessed the connectivity of tau epicenters to cortical regions of interest using a 3-T resting-state functional magnetic resonance imaging template derived from age-matched healthy elderly controls. RESULTS: In 4R tauopathy patients, we found that higher regional tau PET covaries with elevated TSPO-PET across brain regions that are functionally connected to each other (ß = 0.414, P < 0.001). Microglial activation follows similar distribution patterns as tau and distributes primarily across brain regions strongly connected to patient-specific tau epicenters (ß = -0.594, P < 0.001). In these regions, microglial activation spatially parallels tau distribution detectable with 18F-PI-2620 PET. CONCLUSIONS: Our findings indicate that the spatial expansion of microglial activation parallels tau distribution across brain regions that are functionally connected to each other, suggesting that tau and inflammation are closely interrelated in patients with 4R tauopathies. The combination of in vivo tau and inflammatory biomarkers could therefore support the development of immunomodulatory strategies for disease-modifying treatments in these conditions. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

8.
Comput Struct Biotechnol J ; 23: 2580-2594, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39021582

RESUMEN

Hydroxylation of prolines to 4-trans-hydroxyproline (Hyp) is mediated by prolyl-4 hydroxylases (P4Hs). In plants, Hyps occur in Hydroxyproline-rich glycoproteins (HRGPs), and are frequently O-glycosylated. While both modifications are important, e.g. for cell wall stability, they are undesired in plant-made pharmaceuticals. Sequence motifs for prolyl-hydroxylation were proposed but did not include data from mosses, such as Physcomitrella. We identified six moss P4Hs by phylogenetic reconstruction. Our analysis of 73 Hyps in 24 secretory proteins from multiple mass spectrometry datasets revealed that prolines near other prolines, alanine, serine, threonine and valine were preferentially hydroxylated. About 95 % of Hyps were predictable with combined established methods. In our data, AOV was the most frequent pattern. A combination of 443 AlphaFold models and MS data with 3000 prolines found Hyps mainly on protein surfaces in disordered regions. Moss-produced human erythropoietin (EPO) exhibited O-glycosylation with arabinose chains on two Hyps. This modification was significantly reduced in a p4h1 knock-out (KO) Physcomitrella mutant. Quantitative proteomics with different p4h mutants revealed specific changes in protein amounts, and a modified prolyl-hydroxylation pattern, suggesting a differential function of the Physcomitrella P4Hs. Quantitative RT-PCR revealed a differential effect of single p4h KOs on the expression of the other five p4h genes, suggesting a partial compensation of the mutation. AlphaFold-Multimer models for Physcomitrella P4H1 and its target EPO peptide superposed with the crystal structure of Chlamydomonas P4H1 suggested significant amino acids in the active centre of the enzyme and revealed differences between P4H1 and the other Physcomitrella P4Hs.

9.
Mov Disord ; 39(8): 1329-1342, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38825840

RESUMEN

BACKGROUND: Several magnetic resonance imaging (MRI) measures have been suggested as progression biomarkers in progressive supranuclear palsy (PSP), and some PSP staging systems have been recently proposed. OBJECTIVE: Comparing structural MRI measures and staging systems in tracking atrophy progression in PSP and estimating the sample size to use them as endpoints in clinical trials. METHODS: Progressive supranuclear palsy-Richardson's syndrome (PSP-RS) patients with one-year-follow-up longitudinal brain MRI were selected from the placebo arms of international trials (NCT03068468, NCT01110720, NCT01049399) and the DescribePSP cohort. The discovery cohort included patients from the NCT03068468 trial; the validation cohort included patients from other sources. Multisite age-matched healthy controls (HC) were included for comparison. Several MRI measures were compared: automated atlas-based volumetry (44 regions), automated planimetric measures of brainstem regions, and four previously described staging systems, applied to volumetric data. RESULTS: Of 508 participants, 226 PSP patients including discovery (n = 121) and validation (n = 105) cohorts, and 251 HC were included. In PSP patients, the annualized percentage change of brainstem and midbrain volume, and a combined index including midbrain, frontal lobe, and third ventricle volume change, were the progression biomarkers with the highest effect size in both cohorts (discovery: >1.6; validation cohort: >1.3). These measures required the lowest sample sizes (n < 100) to detect 30% atrophy progression, compared with other volumetric/planimetric measures and staging systems. CONCLUSIONS: This evidence may inform the selection of imaging endpoints to assess the treatment efficacy in reducing brain atrophy rate in PSP clinical trials, with automated atlas-based volumetry requiring smaller sample size than staging systems and planimetry to observe significant treatment effects. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Atrofia , Progresión de la Enfermedad , Imagen por Resonancia Magnética , Parálisis Supranuclear Progresiva , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atrofia/patología , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Estudios de Cohortes , Imagen por Resonancia Magnética/métodos , Parálisis Supranuclear Progresiva/diagnóstico por imagen , Parálisis Supranuclear Progresiva/patología , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Brain ; 147(7): 2428-2439, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38842726

RESUMEN

Four-repeat (4R) tauopathies are neurodegenerative diseases characterized by cerebral accumulation of 4R tau pathology. The most prominent 4R tauopathies are progressive supranuclear palsy (PSP) and corticobasal degeneration characterized by subcortical tau accumulation and cortical neuronal dysfunction, as shown by PET-assessed hypoperfusion and glucose hypometabolism. Yet, there is a spatial mismatch between subcortical tau deposition patterns and cortical neuronal dysfunction, and it is unclear how these two pathological brain changes are interrelated. Here, we hypothesized that subcortical tau pathology induces remote neuronal dysfunction in functionally connected cortical regions to test a pathophysiological model that mechanistically links subcortical tau accumulation to cortical neuronal dysfunction in 4R tauopathies. We included 51 Aß-negative patients with clinically diagnosed PSP variants (n = 26) or corticobasal syndrome (n = 25) who underwent structural MRI and 18F-PI-2620 tau-PET. 18F-PI-2620 tau-PET was recorded using a dynamic one-stop-shop acquisition protocol to determine an early 0.5-2.5 min post tracer-injection perfusion window for assessing cortical neuronal dysfunction, as well as a 20-40 min post tracer-injection window to determine 4R-tau load. Perfusion-PET (i.e. early window) was assessed in 200 cortical regions, and tau-PET was assessed in 32 subcortical regions of established functional brain atlases. We determined tau epicentres as subcortical regions with the highest 18F-PI-2620 tau-PET signal and assessed the connectivity of tau epicentres to cortical regions of interest using a resting-state functional MRI-based functional connectivity template derived from 69 healthy elderly controls from the ADNI cohort. Using linear regression, we assessed whether: (i) higher subcortical tau-PET was associated with reduced cortical perfusion; and (ii) cortical perfusion reductions were observed preferentially in regions closely connected to subcortical tau epicentres. As hypothesized, higher subcortical tau-PET was associated with overall lower cortical perfusion, which remained consistent when controlling for cortical tau-PET. Using group-average and subject-level PET data, we found that the seed-based connectivity pattern of subcortical tau epicentres aligned with cortical perfusion patterns, where cortical regions that were more closely connected to the tau epicentre showed lower perfusion. Together, subcortical tau-accumulation is associated with remote perfusion reductions indicative of neuronal dysfunction in functionally connected cortical regions in 4R-tauopathies. This suggests that subcortical tau pathology may induce cortical dysfunction, which may contribute to clinical disease manifestation and clinical heterogeneity.


Asunto(s)
Corteza Cerebral , Tomografía de Emisión de Positrones , Parálisis Supranuclear Progresiva , Tauopatías , Proteínas tau , Humanos , Masculino , Femenino , Tomografía de Emisión de Positrones/métodos , Anciano , Tauopatías/diagnóstico por imagen , Tauopatías/metabolismo , Tauopatías/patología , Proteínas tau/metabolismo , Persona de Mediana Edad , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/metabolismo , Corteza Cerebral/patología , Parálisis Supranuclear Progresiva/diagnóstico por imagen , Parálisis Supranuclear Progresiva/metabolismo , Parálisis Supranuclear Progresiva/patología , Parálisis Supranuclear Progresiva/fisiopatología , Imagen por Resonancia Magnética/métodos
12.
J Thorac Dis ; 16(5): 2875-2893, 2024 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-38883623

RESUMEN

Background: Differentiating inflammatory from malignant lung lesions continues to be challenging in clinical routine, frequently requiring invasive methods like biopsy. Therefore, we aimed to investigate if inflammatory and malignant pulmonary lesions could be distinguished noninvasively using radiomics of apparent diffusion coefficient (ADC) maps and radiomic feature maps calculated from T2-weighted (T2w) 3 Tesla (3T) magnetic resonance imaging (MRI) of the lung. Methods: Fifty-four patients with an unclear pulmonary lesion on computed tomography (CT) were prospectively included and examined by 3T MRI with T2w and diffusion-weighted sequences (b values of 50 and 800). ADC maps were calculated automatically. All patients underwent biopsy or bronchoalveolar lavage (BAL). Sixteen patients were excluded (e.g., motion artifacts), leaving 19 patients each with malignant and inflammatory pulmonary lesions. Target lesions were defined by biopsy or as the largest lesion (BAL-based pathogen detection), and two readers placed volumes of interest (VOIs) around the lesions on T2w images and ADC maps. One hundred and seven features were conventionally extracted from the ADC maps using PyRadiomics. T2w images were converted to 107 parametric feature maps per patient using a PyRadiomics-based, pretested software tool developed by our group. VOIs were copied from T2w images to T2 maps for feature quantification. Features were tested for significant differences using the Mann-Whitney U-test. Diagnostic performance was assessed using receiver operating characteristic (ROC) analysis and interreader agreement by intraclass correlation coefficients (ICCs). Results: Fifty-eight features derived from ADC maps differed significantly between malignant and inflammatory pulmonary lesions, with areas under the curve (AUCs) >0.90 for 5 and >0.80 for 27 features, compared with 67 features from T2 maps (5 features with AUCs >0.80). ICCs were excellent throughout. Conclusions: ADC and T2 maps differentiate inflammatory and malignant pulmonary lesions with outstanding (ADC) and excellent (T2w derived feature maps) diagnostic performance. MRI could thus guide the further diagnostic workup and a timely initiation of the appropriate therapy.

13.
Appl Microbiol Biotechnol ; 108(1): 310, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38662130

RESUMEN

Poly-hydroxybutyrate (PHB) is an environmentally friendly alternative for conventional fossil fuel-based plastics that is produced by various microorganisms. Large-scale PHB production is challenging due to the comparatively higher biomanufacturing costs. A PHB overproducer is the haloalkaliphilic bacterium Halomonas campaniensis, which has low nutritional requirements and can grow in cultures with high salt concentrations, rendering it resistant to contamination. Despite its virtues, the metabolic capabilities of H. campaniensis as well as the limitations hindering higher PHB production remain poorly studied. To address this limitation, we present HaloGEM, the first high-quality genome-scale metabolic network reconstruction, which encompasses 888 genes, 1528 reactions (1257 gene-associated), and 1274 metabolites. HaloGEM not only displays excellent agreement with previous growth data and experiments from this study, but it also revealed nitrogen as a limiting nutrient when growing aerobically under high salt concentrations using glucose as carbon source. Among different nitrogen source mixtures for optimal growth, HaloGEM predicted glutamate and arginine as a promising mixture producing increases of 54.2% and 153.4% in the biomass yield and PHB titer, respectively. Furthermore, the model was used to predict genetic interventions for increasing PHB yield, which were consistent with the rationale of previously reported strategies. Overall, the presented reconstruction advances our understanding of the metabolic capabilities of H. campaniensis for rationally engineering this next-generation industrial biotechnology platform. KEY POINTS: A comprehensive genome-scale metabolic reconstruction of H. campaniensis was developed. Experiments and simulations predict N limitation in minimal media under aerobiosis. In silico media design increased experimental biomass yield and PHB titer.


Asunto(s)
Halomonas , Hidroxibutiratos , Nitrógeno , Poliésteres , Polihidroxibutiratos , Halomonas/metabolismo , Halomonas/genética , Halomonas/crecimiento & desarrollo , Nitrógeno/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Redes y Vías Metabólicas/genética , Biomasa , Glucosa/metabolismo
14.
Nat Commun ; 15(1): 3522, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664386

RESUMEN

Despite decades of research, the influence of climate on the export of dissolved organic carbon (DOC) from soil remains poorly constrained, adding uncertainty to global carbon models. The limited temporal range of contemporary monitoring data, ongoing climate reorganisation and confounding anthropogenic activities muddy the waters further. Here, we reconstruct DOC leaching over the last ~14,000 years using alpine environmental archives (two speleothems and one lake sediment core) across 4° of latitude from Te Waipounamu/South Island of Aotearoa New Zealand. We selected broadly comparable palaeoenvironmental archives in mountainous catchments, free of anthropogenically-induced landscape changes prior to ~1200 C.E. We show that warmer temperatures resulted in increased allochthonous DOC export through the Holocene, most notably during the Holocene Climatic Optimum (HCO), which was some 1.5-2.5 °C warmer than the late pre-industrial period-then decreased during the cooler mid-Holocene. We propose that temperature exerted the key control on the observed doubling to tripling of soil DOC export during the HCO, presumably via temperature-mediated changes in vegetative soil C inputs and microbial degradation rates. Future warming may accelerate DOC export from mountainous catchments, with implications for the global carbon cycle and water quality.

15.
Nat Commun ; 15(1): 3521, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664456

RESUMEN

Recently, a novel cyclo-heptapeptide composed of alternating D,L-amino acids and a unique thiazolidine heterocycle, called lugdunin, was discovered, which is produced by the nasal and skin commensal Staphylococcus lugdunensis. Lugdunin displays potent antimicrobial activity against a broad spectrum of Gram-positive bacteria, including challenging-to-treat methicillin-resistant Staphylococcus aureus (MRSA). Lugdunin specifically inhibits target bacteria by dissipating their membrane potential. However, the precise mode of action of this new class of fibupeptides remains largely elusive. Here, we disclose the mechanism by which lugdunin rapidly destabilizes the bacterial membrane potential using an in vitro approach. The peptide strongly partitions into lipid compositions resembling Gram-positive bacterial membranes but less in those harboring the eukaryotic membrane component cholesterol. Upon insertion, lugdunin forms hydrogen-bonded antiparallel ß-sheets by the formation of peptide nanotubes, as demonstrated by ATR-FTIR spectroscopy and molecular dynamics simulations. These hydrophilic nanotubes filled with a water wire facilitate not only the translocation of protons but also of monovalent cations as demonstrated by voltage-clamp experiments on black lipid membranes. Collectively, our results provide evidence that the natural fibupeptide lugdunin acts as a peptidic channel that is spontaneously formed by an intricate stacking mechanism, leading to the dissipation of a bacterial cell's membrane potential.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Simulación de Dinámica Molecular , Agua/química , Potenciales de la Membrana/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Membrana Celular/química , Antibacterianos/farmacología , Antibacterianos/química , Lípidos de la Membrana/química , Lípidos de la Membrana/metabolismo , Staphylococcus lugdunensis/efectos de los fármacos , Staphylococcus lugdunensis/química , Staphylococcus lugdunensis/metabolismo , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Pruebas de Sensibilidad Microbiana , Nanotubos/química , Péptidos Antimicrobianos/química , Péptidos Antimicrobianos/farmacología
16.
Clin Transl Radiat Oncol ; 46: 100756, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38450219

RESUMEN

Purpose: Stereotactic body radiotherapy (SBRT) is an effective treatment for adrenal gland metastases, but it is technically challenging and there are concerns about toxicity. We performed a multi-institutional pooled retrospective analysis to study clinical outcomes and toxicities after MR-guided SBRT (MRgSBRT) using for adrenal gland metastases. Methods and Materials: Clinical and dosimetric data of patients treated with MRgSBRT on a 0.35 T MR-Linac at 11 institutions between 2016 and 2022 were analyzed. Local control (LC), local progression-free survival (LPFS), distant progression-free survival (DPFS) and overall survival (OS) were estimated using Kaplan-Meier method and log-rank test. Results: A total of 255 patients (269 adrenal metastases) were included. Metastatic pattern was solitary in 25.9 % and oligometastatic in 58.0 % of patients. Median total dose was 45 Gy (range, 16-60 Gy) in a median of 5 fractions, and the median BED10 was 100 Gy (range, 37.5-132.0 Gy). Adaptation was done in 87.4 % of delivered fractions based on the individual clinicians' judgement. The 1- and 2- year LPFS rates were 94.0 % (95 % CI: 90.7-97.3 %) and 88.3 % (95 % CI: 82.4-94.2 %), respectively and only 2 patients (0.8 %) experienced grade 3 + toxicity. No local recurrences were observed after treatment to a total dose of BED10 > 100 Gy, with single fraction or fractional dose of > 10 Gy. Conclusions: This is a large retrospective multi-institutional study to evaluate the treatment outcomes and toxicities with MRgSBRT in over 250 patients, demonstrating the need for frequent adaptation in 87.4 % of delivered fractions to achieve a 1- year LPFS rate of 94 % and less than 1 % rate of grade 3 + toxicity. Outcomes analysis in 269 adrenal lesions revealed improved outcomes with delivery of a BED10 > 100 Gy, use of single fraction SBRT and with fraction doses > 10 Gy, providing benchmarks for future clinical trials.

17.
Cardiovasc Revasc Med ; 65: 18-24, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38503645

RESUMEN

BACKGROUND: More than moderate tricuspid regurgitation (TR) is associated with high mortality. Surgical tricuspid valve repair and replacements are rarely performed due to high operative mortality risk, mainly attributed to late presentation. Novel transcatheter tricuspid valve intervention (TTVI) devices are being developed as an alternative to surgery. The population of patients presenting to tertiary care centers who can benefit from TTVI has not been well defined. METHODS: We retrospectively analyzed 12,677 consecutive 2D echocardiograms completed at our tertiary care center between March 2021 and March 2022 and identified hospitalized patients with more than moderate TR. A total of 569 patients were included in this study. Clinical and echocardiographic data were collected by individual chart review. We used the European Society of Cardiology (ESC) guidelines on the management of valvular disease to retrospectively assign patients to medical, surgical, or transcatheter therapy. RESULTS: 458 patients (80.5 %) were assigned to medical therapy, 57 (10.0 %) were assigned to TTVI, and 54 (9.5 %) were assigned to tricuspid valve surgery. Of note, 75.7 % (431/569) of patients were precluded from any intervention due to advanced disease, and only 4.7 % (27/569) presented too early for intervention, being both asymptomatic and without RV dilatation. CONCLUSION: Only 10.0 % of patients presenting to a tertiary care center with significant TR would be candidates for TTVI when these technologies are approved in the United States. Earlier identification and treatment of TR could increase the number of patients who may benefit from interventions including TTVI.


Asunto(s)
Cateterismo Cardíaco , Implantación de Prótesis de Válvulas Cardíacas , Índice de Severidad de la Enfermedad , Insuficiencia de la Válvula Tricúspide , Válvula Tricúspide , Humanos , Insuficiencia de la Válvula Tricúspide/diagnóstico por imagen , Insuficiencia de la Válvula Tricúspide/cirugía , Insuficiencia de la Válvula Tricúspide/fisiopatología , Insuficiencia de la Válvula Tricúspide/mortalidad , Estudios Retrospectivos , Válvula Tricúspide/diagnóstico por imagen , Válvula Tricúspide/cirugía , Válvula Tricúspide/fisiopatología , Masculino , Femenino , Anciano , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Resultado del Tratamiento , Cateterismo Cardíaco/efectos adversos , Cateterismo Cardíaco/instrumentación , Persona de Mediana Edad , Factores de Riesgo , Anciano de 80 o más Años , Factores de Tiempo , Medición de Riesgo , Toma de Decisiones Clínicas , Selección de Paciente , Centros de Atención Terciaria , Pacientes Internos
18.
Am J Forensic Med Pathol ; 45(2): 103-110, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38411190

RESUMEN

ABSTRACT: Multiple studies have documented various factors that influence or determine forensic pathologist classification of manner of death. There do not appear to be any published studies on manner of death classification specifically regarding arrest-related deaths (ARDs). The goal of this study was to consider a large body of cases of nonfirearm ARDs to analyze the homicide classification with regards to numerous decedent and practitioner (medical examiner/coroner [ME/C]) variables. We analyzed 1145 US autopsy reports from the years 2006-2020, inclusive, and considered decedent variables of age, ethnicity, height, weight, body mass index, toxicology, and mention of a conducted electrical weapon and ME/C influence variables of gender, country region, and year. We found that the homicide classification likelihood increased by a factor of 1.04-1.05 per year, 1.34-1.37 for a female medical examiner, and 1.4-1.5 going from Southern states to Western states. There is an increasing trend for ME/C to label nonfirearm ARDs as homicides in the United States. The homicide classification is more common in Western states and less common in Southern states, and it was more common with a female ME/C.


Asunto(s)
Homicidio , Humanos , Homicidio/estadística & datos numéricos , Femenino , Masculino , Adulto , Persona de Mediana Edad , Anciano , Adulto Joven , Adolescente , Estados Unidos , Niño , Preescolar , Médicos Forenses , Lactante , Anciano de 80 o más Años , Distribución por Sexo , Lesiones por Armas Conductoras de Energía , Distribución por Edad , Causas de Muerte , Recién Nacido , Peso Corporal
19.
Materials (Basel) ; 17(2)2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38255475

RESUMEN

In Bolivia, lateritic soils are common in humid tropical regions and can be used in the construction industry as an alternative to materials that cause a negative environmental impact, such as cement. The production of Portland cement causes environmental issues like significant greenhouse gas emissions and air pollution. To address this problem, geopolymers have been introduced as an alternative binder with low CO2 emissions. In this regard, geopolymers based on lateritic clays have been studied mineralogically, chemically, and on their compressive strength separately. However, there are still no studies on lateritic clays present in Bolivia and their mechanical, mineralogical, and chemical properties combined in a geopolymer. Therefore, this present research proposes the evaluation of a geopolymer made from laterite clays. Compression and flexural tests were carried out, along with mineralogical and chemical analyses on mortar and geopolymer cubes and prisms. The results indicate that the laterite clay-based geopolymer has lower compressive strength compared to Portland cement IP (cement type I with the addition of pozzolana) mortar. However, the flexural strength tests show a slight increase in the case of the geopolymer.

20.
Plant Cell Rep ; 43(2): 43, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-38246952

RESUMEN

KEY MESSAGE: Characterization of Physcomitrella 3'UTRs across different promoters yields endogenous single and double terminators for usage in molecular pharming. The production of recombinant proteins for health applications accounts for a large share of the biopharmaceutical market. While many drugs are produced in microbial and mammalian systems, plants gain more attention as expression hosts to produce eukaryotic proteins. In particular, the good manufacturing practice (GMP)-compliant moss Physcomitrella (Physcomitrium patens) has outstanding features, such as excellent genetic amenability, reproducible bioreactor cultivation, and humanized protein glycosylation patterns. In this study, we selected and characterized novel terminators for their effects on heterologous gene expression. The Physcomitrella genome contains 53,346 unique 3'UTRs (untranslated regions) of which 7964 transcripts contain at least one intron. Over 91% of 3'UTRs exhibit more than one polyadenylation site, indicating the prevalence of alternative polyadenylation in Physcomitrella. Out of all 3'UTRs, 14 terminator candidates were selected and characterized via transient Dual-Luciferase assays, yielding a collection of endogenous terminators performing equally high as established heterologous terminators CaMV35S, AtHSP90, and NOS. High performing candidates were selected for testing as double terminators which impact reporter levels, dependent on terminator identity and positioning. Testing of 3'UTRs among the different promoters NOS, CaMV35S, and PpActin5 showed an increase of more than 1000-fold between promoters PpActin5 and NOS, whereas terminators increased reporter levels by less than tenfold, demonstrating the stronger effect promoters play as compared to terminators. Among selected terminator attributes, the number of polyadenylation sites as well as polyadenylation signals were found to influence terminator performance the most. Our results improve the biotechnology platform Physcomitrella and further our understanding of how terminators influence gene expression in plants in general.


Asunto(s)
Briófitas , Bryopsida , Animales , Bryopsida/genética , Regiones no Traducidas 3' , Agricultura Molecular , Expresión Génica , Mamíferos
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