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1.
Cell ; 186(10): 2111-2126.e20, 2023 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-37172564

RESUMEN

Microglia are specialized brain-resident macrophages that play crucial roles in brain development, homeostasis, and disease. However, until now, the ability to model interactions between the human brain environment and microglia has been severely limited. To overcome these limitations, we developed an in vivo xenotransplantation approach that allows us to study functionally mature human microglia (hMGs) that operate within a physiologically relevant, vascularized immunocompetent human brain organoid (iHBO) model. Our data show that organoid-resident hMGs gain human-specific transcriptomic signatures that closely resemble their in vivo counterparts. In vivo two-photon imaging reveals that hMGs actively engage in surveilling the human brain environment, react to local injuries, and respond to systemic inflammatory cues. Finally, we demonstrate that the transplanted iHBOs developed here offer the unprecedented opportunity to study functional human microglia phenotypes in health and disease and provide experimental evidence for a brain-environment-induced immune response in a patient-specific model of autism with macrocephaly.


Asunto(s)
Microglía , Organoides , Humanos , Encéfalo , Macrófagos , Fenotipo
2.
Nat Immunol ; 22(1): 53-66, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33230330

RESUMEN

Regenerative stem cell-like memory (TSCM) CD8+ T cells persist longer and produce stronger effector functions. We found that MEK1/2 inhibition (MEKi) induces TSCM that have naive phenotype with self-renewability, enhanced multipotency and proliferative capacity. This is achieved by delaying cell division and enhancing mitochondrial biogenesis and fatty acid oxidation, without affecting T cell receptor-mediated activation. DNA methylation profiling revealed that MEKi-induced TSCM cells exhibited plasticity and loci-specific profiles similar to bona fide TSCM isolated from healthy donors, with intermediate characteristics compared to naive and central memory T cells. Ex vivo, antigenic rechallenge of MEKi-treated CD8+ T cells showed stronger recall responses. This strategy generated T cells with higher efficacy for adoptive cell therapy. Moreover, MEKi treatment of tumor-bearing mice also showed strong immune-mediated antitumor effects. In conclusion, we show that MEKi leads to CD8+ T cell reprogramming into TSCM that acts as a reservoir for effector T cells with potent therapeutic characteristics.


Asunto(s)
Antineoplásicos/farmacología , Linfocitos T CD8-positivos/efectos de los fármacos , Memoria Inmunológica/efectos de los fármacos , Inmunoterapia Adoptiva , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Neoplasias/terapia , Células Madre/citología , Animales , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Ciclo Celular/efectos de los fármacos , Humanos , Memoria Inmunológica/inmunología , Ratones , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Receptores de Antígenos de Linfocitos T/fisiología , Microambiente Tumoral
3.
Cell ; 167(4): 897-914, 2016 Nov 03.
Artículo en Inglés | MEDLINE | ID: mdl-27814520

RESUMEN

The dentate gyrus of the mammalian hippocampus continuously generates new neurons during adulthood. These adult-born neurons become functionally active and are thought to contribute to learning and memory, especially during their maturation phase, when they have extraordinary plasticity. In this Review, we discuss the molecular machinery involved in the generation of new neurons from a pool of adult neural stem cells and their integration into functional hippocampal circuits. We also summarize the potential functions of these newborn neurons in the adult brain, their contribution to behavior, and their relevance to disease.


Asunto(s)
Células Madre Adultas/citología , Hipocampo/citología , Hipocampo/fisiología , Células-Madre Neurales/citología , Neurogénesis , Células Madre Adultas/metabolismo , Animales , Humanos , Trastornos Mentales/patología , Trastornos Mentales/fisiopatología , Células-Madre Neurales/metabolismo , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/fisiopatología
4.
Proc Natl Acad Sci U S A ; 121(23): e2407437121, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38814864

RESUMEN

The accessory protease transmembrane protease serine 2 (TMPRSS2) enhances severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uptake into ACE2-expressing cells, although how increased entry impacts downstream viral and host processes remains unclear. To investigate this in more detail, we performed infection assays in engineered cells promoting ACE2-mediated entry with and without TMPRSS2 coexpression. Electron microscopy and inhibitor experiments indicated TMPRSS2-mediated cell entry was associated with increased virion internalization into endosomes, and partially dependent upon clathrin-mediated endocytosis. TMPRSS2 increased panvariant uptake efficiency and enhanced early rates of virus replication, transcription, and secretion, with variant-specific profiles observed. On the host side, transcriptional profiling confirmed the magnitude of infection-induced antiviral and proinflammatory responses were linked to uptake efficiency, with TMPRSS2-assisted entry boosting early antiviral responses. In addition, TMPRSS2-enhanced infections increased rates of cytopathology, apoptosis, and necrosis and modulated virus secretion kinetics in a variant-specific manner. On the virus side, convergent signatures of cell-uptake-dependent innate immune induction were recorded in viral genomes, manifesting as switches in dominant coupled Nsp3 residues whose frequencies were correlated to the magnitude of the cellular response to infection. Experimentally, we demonstrated that selected Nsp3 mutations conferred enhanced interferon antagonism. More broadly, we show that TMPRSS2 orthologues from evolutionarily diverse mammals facilitate panvariant enhancement of cell uptake. In summary, our study uncovers previously unreported associations, linking cell entry efficiency to innate immune activation kinetics, cell death rates, virus secretion dynamics, and convergent selection of viral mutations. These data expand our understanding of TMPRSS2's role in the SARS-CoV-2 life cycle and confirm its broader significance in zoonotic reservoirs and animal models.


Asunto(s)
COVID-19 , Inmunidad Innata , SARS-CoV-2 , Serina Endopeptidasas , Internalización del Virus , SARS-CoV-2/inmunología , SARS-CoV-2/fisiología , SARS-CoV-2/metabolismo , Humanos , Serina Endopeptidasas/metabolismo , Serina Endopeptidasas/genética , COVID-19/virología , COVID-19/inmunología , COVID-19/metabolismo , Enzima Convertidora de Angiotensina 2/metabolismo , Enzima Convertidora de Angiotensina 2/genética , Replicación Viral , Animales , Endocitosis , Células HEK293 , Chlorocebus aethiops , Citología
5.
Chem Rev ; 124(5): 2327-2351, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38408312

RESUMEN

Polyethylene deconstruction to reusable smaller molecules is hindered by the chemical inertness of its hydrocarbon chains. Pyrolysis and related approaches commonly require high temperatures, are energy-intensive, and yield mixtures of multiple classes of compounds. Selective cleavage reactions under mild conditions (

6.
Proc Natl Acad Sci U S A ; 120(49): e2312261120, 2023 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-38011568

RESUMEN

While radical prostatectomy remains the mainstay of prostate cancer (PCa) treatment, 20 to 40% of patients develop postsurgical biochemical recurrence (BCR). A particularly challenging clinical cohort includes patients with intermediate-risk disease whose risk stratification would benefit from advanced approaches that complement standard-of-care diagnostic tools. Here, we show that imaging tumor lactate using hyperpolarized 13C MRI and spatial metabolomics identifies BCR-positive patients in two prospective intermediate-risk surgical cohorts. Supported by spatially resolved tissue analysis of established glycolytic biomarkers, this study provides the rationale for multicenter trials of tumor metabolic imaging as an auxiliary tool to support PCa treatment decision-making.


Asunto(s)
Antígeno Prostático Específico , Neoplasias de la Próstata , Masculino , Humanos , Antígeno Prostático Específico/análisis , Ácido Láctico , Estudios Prospectivos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/cirugía , Próstata/patología , Prostatectomía/métodos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Estudios Retrospectivos
7.
Mol Biol Evol ; 41(4)2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38573520

RESUMEN

Visual systems adapt to different light environments through several avenues including optical changes to the eye and neurological changes in how light signals are processed and interpreted. Spectral sensitivity can evolve via changes to visual pigments housed in the retinal photoreceptors through gene duplication and loss, differential and coexpression, and sequence evolution. Frogs provide an excellent, yet understudied, system for visual evolution research due to their diversity of ecologies (including biphasic aquatic-terrestrial life cycles) that we hypothesize imposed different selective pressures leading to adaptive evolution of the visual system, notably the opsins that encode the protein component of the visual pigments responsible for the first step in visual perception. Here, we analyze the diversity and evolution of visual opsin genes from 93 new eye transcriptomes plus published data for a combined dataset spanning 122 frog species and 34 families. We find that most species express the four visual opsins previously identified in frogs but show evidence for gene loss in two lineages. Further, we present evidence of positive selection in three opsins and shifts in selective pressures associated with differences in habitat and life history, but not activity pattern. We identify substantial novel variation in the visual opsins and, using microspectrophotometry, find highly variable spectral sensitivities, expanding known ranges for all frog visual pigments. Mutations at spectral-tuning sites only partially account for this variation, suggesting that frogs have used tuning pathways that are unique among vertebrates. These results support the hypothesis of adaptive evolution in photoreceptor physiology across the frog tree of life in response to varying environmental and ecological factors and further our growing understanding of vertebrate visual evolution.


Asunto(s)
Opsinas , Pigmentos Retinianos , Humanos , Animales , Opsinas/genética , Anuros/genética , Duplicación de Gen , Microespectrofotometría
8.
Br J Cancer ; 130(8): 1377-1387, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38396173

RESUMEN

BACKGROUND/OBJECTIVE: To explore the anti-tumour activity of combining AKT inhibition and docetaxel in PTEN protein null and WT prostate tumours. METHODS: Mechanisms associated with docetaxel capivasertib treatment activity in prostate cancer were examined using a panel of in vivo tumour models and cell lines. RESULTS: Combining docetaxel and capivasertib had increased activity in PTEN null and WT prostate tumour models in vivo. In vitro short-term docetaxel treatment caused cell cycle arrest in the majority of cells. However, a sub-population of docetaxel-persister cells did not undergo G2/M arrest but upregulated phosphorylation of PI3K/AKT pathway effectors GSK3ß, p70S6K, 4E-BP1, but to a lesser extent AKT. In vivo acute docetaxel treatment induced p70S6K and 4E-BP1 phosphorylation. Treating PTEN null and WT docetaxel-persister cells with capivasertib reduced PI3K/AKT pathway activation and cell cycle progression. In vitro and in vivo it reduced proliferation and increased apoptosis or DNA damage though effects were more marked in PTEN null cells. Docetaxel-persister cells were partly reliant on GSK3ß as a GSK3ß inhibitor AZD2858 reversed capivasertib-induced apoptosis and DNA damage. CONCLUSION: Capivasertib can enhance anti-tumour effects of docetaxel by targeting residual docetaxel-persister cells, independent of PTEN status, to induce apoptosis and DNA damage in part through GSK3ß.


Asunto(s)
Neoplasias de la Próstata , Proteínas Proto-Oncogénicas c-akt , Pirimidinas , Pirroles , Masculino , Humanos , Docetaxel/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Proteínas Quinasas S6 Ribosómicas 70-kDa/farmacología , Transducción de Señal , Apoptosis , Fosfatidilinositol 3-Quinasas/metabolismo , Glucógeno Sintasa Quinasa 3 beta , Línea Celular Tumoral , Puntos de Control de la Fase G2 del Ciclo Celular , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/metabolismo , Fosfohidrolasa PTEN/metabolismo
9.
J Med Virol ; 96(10): e29935, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39323094

RESUMEN

Studies have pointed to a decisive role of autoantibodies in the context of sepsis and severe Coronavirus disease 2019 (COVID-19), which itself often fulfills the criteria for sepsis, including dysregulated immune responses and organ dysfunction. To directly compare and further analyze the autoantibody profiles of sepsis patients with and without COVID-19, the luciferase immunoprecipitation systems (LIPS) assay was used to measure the levels of autoantibodies against a variety of clinically relevant cytokines, lung-associated proteins, other autoantigens, and antibodies against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In addition, cytokine titers were measured with the LEGENDplex™ Human Antivirus Response Panel. We observed significantly increased levels of autoantibodies in 59% of the COVID-19-Sepsis group compared to 48% of the Sepsis group. Significant differences were identified between the groups for the levels of autoantibodies against gATPase. The cytokine levels of interferon (IFN)-λ1 and IP-10 were higher in the COVID-19-Sepsis group compared to the Sepsis group. Additional correlations between autoantibodies, cytokines and 30-day survival could be demonstrated, suggesting varied underlying pathological mechanisms. Elevated levels of cytokines and autoantibodies may serve as prognostic indicators for the survival probability of sepsis patients, highlighting the intricate relationship between immune responses and patient outcomes in the context of both sepsis and COVID-19.


Asunto(s)
Autoanticuerpos , COVID-19 , Citocinas , Sepsis , Humanos , COVID-19/inmunología , COVID-19/mortalidad , COVID-19/sangre , Autoanticuerpos/sangre , Sepsis/inmunología , Sepsis/mortalidad , Sepsis/sangre , Citocinas/sangre , Masculino , Femenino , Persona de Mediana Edad , Anciano , SARS-CoV-2/inmunología , Adulto , Pronóstico , Anciano de 80 o más Años , Anticuerpos Antivirales/sangre
10.
Mol Phylogenet Evol ; 198: 108130, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38889862

RESUMEN

Unusually for oceanic islands, the granitic Seychelles host multiple lineages of endemic amphibians. This includes an ancient (likely ca. 60 million years) radiation of eight caecilian species, most of which occur on multiple islands.These caecilians have a complicated taxonomic history and their phylogenetic inter-species relationships have been difficult to resolve. Double-digest RAD sequencing (ddRADseq) has been applied extensively to phylogeography and increasingly to phylogenetics but its utility for resolving ancient divergences is less well established. To address this, we applied ddRADseq to generate a genome-wide SNP panel for phylogenomic analyses of the Seychelles caecilians, whose phylogeny has so far not been satisfactorily resolved with traditional DNA markers. Based on 129,154 SNPs, we resolved deep and shallow splits, with strong support. Our findings demonstrate the capability of genome-wide SNPs for evolutionary inference at multiple taxonomic levels and support the recently proposed synonymy of Grandisonia Taylor, 1968 with Hypogeophis Peters, 1879. We revealed three clades of Hypogeophis (large-, medium- and short-bodied) and identify a single origin of the diminutive, stocky-bodied and pointy-snouted phenotype.


Asunto(s)
Anfibios , Filogenia , Polimorfismo de Nucleótido Simple , Animales , Seychelles , Anfibios/genética , Anfibios/clasificación , Filogeografía , Islas , Análisis de Secuencia de ADN
11.
Glob Chang Biol ; 30(1): e17090, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38273483

RESUMEN

Microalgae are the main source of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), essential for the healthy development of most marine and terrestrial fauna including humans. Inverse correlations of algal EPA and DHA proportions (% of total fatty acids) with temperature have led to suggestions of a warming-induced decline in the global production of these biomolecules and an enhanced importance of high latitude organisms for their provision. The cold Arctic Ocean is a potential hotspot of EPA and DHA production, but consequences of global warming are unknown. Here, we combine a full-seasonal EPA and DHA dataset from the Central Arctic Ocean (CAO), with results from 13 previous field studies and 32 cultured algal strains to examine five potential climate change effects; ice algae loss, community shifts, increase in light, nutrients, and temperature. The algal EPA and DHA proportions were lower in the ice-covered CAO than in warmer peripheral shelf seas, which indicates that the paradigm of an inverse correlation of EPA and DHA proportions with temperature may not hold in the Arctic. We found no systematic differences in the summed EPA and DHA proportions of sea ice versus pelagic algae, and in diatoms versus non-diatoms. Overall, the algal EPA and DHA proportions varied up to four-fold seasonally and 10-fold regionally, pointing to strong light and nutrient limitations in the CAO. Where these limitations ease in a warming Arctic, EPA and DHA proportions are likely to increase alongside increasing primary production, with nutritional benefits for a non-ice-associated food web.


Asunto(s)
Diatomeas , Ácidos Grasos Omega-3 , Humanos , Cubierta de Hielo , Océanos y Mares , Regiones Árticas , Ácidos Grasos
12.
Opt Lett ; 49(15): 4098-4101, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090867

RESUMEN

An alternative method for characterizing optical propagation in waveguide structures based on scattered light imaging is presented and demonstrated for the spectral range of 450-980 nm. Propagation losses as low as 1.40 dB/cm are demonstrated in alumina spiral waveguides. AlGaAs-on-insulator waveguides are measured using a tunable laser and compared to cut-back measurements. On AlGaAs, a one-sigma uncertainty of 1.40 and 2.23 dB/cm for TE and TM polarizations is obtained for repetitions of measurements conducted on the same waveguide, highlighting the approach's reproducibility. An open-source toolbox is introduced, allowing for reliable processing of data and estimation of optical propagation losses.

13.
Liver Int ; 2024 Aug 22.
Artículo en Inglés | MEDLINE | ID: mdl-39175256

RESUMEN

BACKGROUND AND AIMS: Severe acute respiratory syndrome coronavirus (SARS-CoV-2) preferentially infects the respiratory tract; however, several studies have implicated a multi-organ involvement. Hepatic dysfunctions caused by SARS-CoV-2 infection have been increasingly recognized and described to correlate with disease severity. To elucidate molecular factors that could contribute towards hepatic infection, we concentrated on microRNAs (miRNAs), a class of small non-coding RNAs that modulate various cellular processes and which are reported to be differentially regulated during liver injury. We aimed to study the infection of primary human hepatocytes (PHH) with SARS-CoV-2 and to evaluate the potential of miRNAs for modulating viral infection. METHODS: We analysed liver autopsies from a coronavirus disease 19 (COVID-19)-positive cohort for the presence of viral RNA using Nanopore sequencing. PHH were used for the infection with SARS-CoV-2. The candidate miRNAs targeting angiotensin converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) were identified using in silico approaches. To discover the potential regulatory mechanism, transfection experiments, qRT-PCRs, western blots and luciferase reporter assays were performed. RESULTS: We could detect SARS-CoV-2 RNA in COVID-19-positive liver autopsies. We show that PHH express ACE2 and TMPRSS2 and can be readily infected with SARS-CoV-2, resulting in robust replication. Transfection of selected miRNA mimics reduced SARS-CoV-2 receptor expression and SARS-CoV-2 burden in PHH. In silico and biochemical analyses supported a potential direct binding of miR-141-3p to the SARS-CoV-2 genome. CONCLUSION: We confirm that PHH are susceptible to SARS-CoV-2 infection and demonstrate selected miRNAs targeting SARS-CoV-2 entry factors and/or the viral genome reduce viral loads. These data provide novel insights into hepatic susceptibility to SARS-CoV-2 and associated dysfunctions in COVID-19.

14.
Am J Obstet Gynecol ; 231(2): 240.e1-240.e11, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38462144

RESUMEN

BACKGROUND: Noninvasive biomarkers that predict surgical treatment response would inform personalized treatments and provide insight into potential biologic pathways underlying endometriosis-associated pain and symptom progression. OBJECTIVE: To use plasma proteins in relation to the persistence of pelvic pain following laparoscopic surgery in predominantly adolescents and young adults with endometriosis using a multiplex aptamer-based proteomics biomarker discovery platform. STUDY DESIGN: We conducted a prospective analysis including 142 participants with laparoscopically-confirmed endometriosis from the Women's Health Study: From Adolescence to Adulthood observational longitudinal cohort with study enrollment from 2012-2018. Biologic samples and patient data were collected with modified World Endometriosis Research Foundation Endometriosis Phenome and Biobanking Harmonization Project tools. In blood collected before laparoscopic ablation or excision of endometriosis, we simultaneously measured 1305 plasma protein levels, including markers for immunity, angiogenesis, and inflammation, using SomaScan. Worsening or persistent postsurgical pelvic pain was defined as having newly developed, persistent (ie, stable), or worsening severity, frequency, or persistent life interference of dysmenorrhea or acyclic pelvic pain at 1-year postsurgery compared with presurgery. We calculated odds ratios and 95% confidence intervals using logistic regression adjusted for age, body mass index, fasting status, and hormone use at blood draw. We applied Ingenuity Pathway Analysis and STRING analysis to identify pathophysiologic pathways and protein interactions. RESULTS: The median age at blood draw was 17 years (interquartile range, 15-19 years), and most participants were White (90%). All had superficial peritoneal lesions only and were treated by excision or ablation. One-year postsurgery, pelvic pain worsened or persisted for 76 (54%) of these participants with endometriosis, whereas pelvic pain improved for 66 (46%). We identified 83 proteins associated with worsening or persistent pelvic pain 1-year postsurgery (nominal P<.05). Compared with those with improved pelvic pain 1-year postsurgery, those with worsening or persistent pelvic pain had higher plasma levels of CD63 antigen (odds ratio, 2.98 [95% confidence interval, 1.44-6.19]) and CD47 (odds ratio, 2.68 [95% confidence interval, 1.28-5.61]), but lower levels of Sonic Hedgehog protein (odds ratio, 0.55 [95% confidence interval, 0.36-0.84]) in presurgical blood. Pathways related to cell migration were up-regulated, and pathways related to angiogenesis were down-regulated in those with worsening or persistent postsurgical pelvic pain compared with those with improved pain. When we examined the change in protein levels from presurgery to postsurgery and its subsequent risk of worsening or persistent postsurgical pain at 1-year follow-up, we observed increasing levels of Sonic Hedgehog protein from presurgery to postsurgery was associated with a 4-fold increase in the risk of postsurgical pain (odds ratio [quartile 4 vs 1], 3.86 [1.04-14.33]). CONCLUSION: Using an aptamer-based proteomics platform, we identified plasma proteins and pathways associated with worsening or persistent pelvic pain postsurgical treatment of endometriosis among adolescents and young adults that may aid in risk stratification of individuals with endometriosis.


Asunto(s)
Biomarcadores , Proteínas Sanguíneas , Endometriosis , Dolor Pélvico , Humanos , Femenino , Endometriosis/cirugía , Endometriosis/sangre , Endometriosis/complicaciones , Adolescente , Dolor Pélvico/sangre , Dolor Pélvico/cirugía , Adulto Joven , Biomarcadores/sangre , Estudios Prospectivos , Adulto , Dolor Postoperatorio/sangre , Estudios Longitudinales , Laparoscopía , Dismenorrea/sangre , Dismenorrea/cirugía , Dismenorrea/etiología , Proteómica
15.
Rapid Commun Mass Spectrom ; 38(6): e9704, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38356092

RESUMEN

RATIONALE: The efficiency of selected ion monitoring (SIM) and selected reaction monitoring (SRM) analyses for the quantification of three mono-, di- and tri-unsaturated highly branched isoprenoid (HBI) alkenes (IP25 , IPSO25 and HBI III, respectively), often used as proxies for the occurrence of Arctic and Antarctic sea ice or the adjacent open waters, was compared. METHODS: Gas chromatography (GC)-mass spectrometry (MS)/SIM and GC/MS/MS/SRM analyses were carried out on dilute solutions made from purified standards of these three HBIs, and then on hydrocarbon fractions of several sediment and sea ice sample extracts. More efficient and specific SRM transitions were selected after collision-induced dissociation of each precursor ion at different collision energies. RESULTS: SRM analysis avoided any overestimation of IP25 resulting from the contribution of the coeluting 13 C mass isotopomer of IPSO25 (M+ ˙ + 2) to the SIM target ion. In contrast, SRM analysis is less reliable for IPSO25 quantification in cases where several regio-isomers are present, likely due to intense double bond migrations following electron impact. In the case of HBI III, SRM analysis constitutes a potentially suitable alternative to SIM analysis, especially in terms of improving limit of detection. CONCLUSIONS: Despite the intense migrations of HBI double bonds under electron ionization, the selected SRM transitions should be more suitable than SIM target ions for IP25 and HBI III quantification in complex hydrocarbon fractions of natural samples. However, the advantage is less evident for IPSO25 due to the presence of numerous regio-isomers.


Asunto(s)
Espectrometría de Masas en Tándem , Terpenos , Cromatografía de Gases y Espectrometría de Masas/métodos , Espectrometría de Masas en Tándem/métodos , Terpenos/análisis , Alquenos/análisis , Cubierta de Hielo , Biomarcadores/análisis
16.
Oecologia ; 205(3-4): 725-737, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38829402

RESUMEN

Plants employ diverse anti-herbivore defences that can covary to form syndromes consisting of multiple traits. Such syndromes are hypothesized to impact herbivores more than individual defences. We studied 16 species of lowland willows occurring in central Europe and explored if their chemical and physical traits form detectable syndromes. We tested for phylogenetic trends in the syndromes and explored whether three herbivore guilds (i.e., generalist leaf-chewers, specialist leaf-chewers, and gallers) are affected more by the detected syndromes or individual traits. The recovered syndromes showed low phylogenetic signal and were mainly defined by investment in concentration, richness, or uniqueness of structurally related phenolic metabolites. Resource acquisition traits or inducible volatile organic compounds exhibited a limited correlation with the syndromes. Individual traits composing the syndromes showed various correlations to the assemblages of herbivores from the three studied guilds. In turn, we found some support for the hypothesis that defence syndromes are composed of traits that provide defence against various herbivores. However, individual traits rather than trait syndromes explained more variation for all studied herbivore assemblages. The detected negative correlations between various phenolics suggest that investment trade-offs may occur primarily among plant metabolites with shared metabolic pathways that may compete for their precursors. Moreover, several traits characterizing the recovered syndromes play additional roles in willows other than defence from herbivory. Taken together, our findings suggest that the detected syndromes did not solely evolve as an anti-herbivore defence.


Asunto(s)
Herbivoria , Salix , Animales , Filogenia , Hojas de la Planta , Europa (Continente)
17.
J Appl Microbiol ; 135(4)2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38637309

RESUMEN

AIMS: To monitor severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) RNA contamination in vehicles operating in England during the pandemic, to better understand transmission risk of SARS-CoV-2 on public transport. METHODS AND RESULTS: We collected 1314 surface samples between December 2020 and April 2022 on trains and buses managed by five different transport operators. The presence of SARS-CoV-2 RNA was investigated through reverse transcription polymerase chain reaction (RT-PCR). SARS-CoV-2 RNA was found on 197 (15%) of the 1314 surfaces sampled, including seat head rests, handholds, and air extract grilles, but the levels of RNA recovered on those samples (median value of 23.4, interquartile range: 14.3-35.4, N gene copies per extraction) made the presence of infectious virus at the time of sampling extremely unlikely. However, detection rates varied over time with peaks broadly coinciding with times of high community transmission, when it was more likely that people infected with SARS-CoV-2 were travelling on public transport. CONCLUSION: During the pandemic, and as in other public spaces, low levels of SARS-CoV-2 RNA were found on surfaces associated with public transport.


Asunto(s)
COVID-19 , ARN Viral , SARS-CoV-2 , COVID-19/transmisión , COVID-19/virología , COVID-19/epidemiología , SARS-CoV-2/genética , SARS-CoV-2/aislamiento & purificación , Inglaterra/epidemiología , ARN Viral/genética , ARN Viral/análisis , ARN Viral/aislamiento & purificación , Humanos , Estudios Longitudinales , Vehículos a Motor , Transportes
18.
Nucleic Acids Res ; 50(D1): D1541-D1552, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34791421

RESUMEN

ProteomicsDB (https://www.ProteomicsDB.org) is a multi-omics and multi-organism resource for life science research. In this update, we present our efforts to continuously develop and expand ProteomicsDB. The major focus over the last two years was improving the findability, accessibility, interoperability and reusability (FAIR) of the data as well as its implementation. For this purpose, we release a new application programming interface (API) that provides systematic access to essentially all data in ProteomicsDB. Second, we release a new open-source user interface (UI) and show the advantages the scientific community gains from such software. With the new interface, two new visualizations of protein primary, secondary and tertiary structure as well an updated spectrum viewer were added. Furthermore, we integrated ProteomicsDB with our deep-neural-network Prosit that can predict the fragmentation characteristics and retention time of peptides. The result is an automatic processing pipeline that can be used to reevaluate database search engine results stored in ProteomicsDB. In addition, we extended the data content with experiments investigating different human biology as well as a newly supported organism.


Asunto(s)
Bases de Datos de Proteínas , Proteínas/clasificación , Proteómica/clasificación , Programas Informáticos , Disciplinas de las Ciencias Biológicas , Humanos , Redes Neurales de la Computación , Proteínas/química
19.
PLoS Genet ; 17(4): e1009500, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33798193

RESUMEN

Localization of oskar mRNA includes two distinct phases: transport from nurse cells to the oocyte, a process typically accompanied by cortical anchoring in the oocyte, followed by posterior localization within the oocyte. Signals within the oskar 3' UTR directing transport are individually weak, a feature previously hypothesized to facilitate exchange between the different localization machineries. We show that alteration of the SL2a stem-loop structure containing the oskar transport and anchoring signal (TAS) removes an inhibitory effect such that in vitro binding by the RNA transport factor, Egalitarian, is elevated as is in vivo transport from the nurse cells into the oocyte. Cortical anchoring within the oocyte is also enhanced, interfering with posterior localization. We also show that mutation of Staufen recognized structures (SRSs), predicted binding sites for Staufen, disrupts posterior localization of oskar mRNA just as in staufen mutants. Two SRSs in SL2a, one overlapping the Egalitarian binding site, are inferred to mediate Staufen-dependent inhibition of TAS anchoring activity, thereby promoting posterior localization. The other three SRSs in the oskar 3' UTR are also required for posterior localization, including two located distant from any known transport signal. Staufen, thus, plays multiple roles in localization of oskar mRNA.


Asunto(s)
Proteínas de Drosophila/genética , Oocitos/crecimiento & desarrollo , Proteínas de Unión al ARN/genética , Animales , Proteínas de Drosophila/ultraestructura , Drosophila melanogaster/genética , Drosophila melanogaster/crecimiento & desarrollo , Secuencias Invertidas Repetidas/genética , Mutación/genética , Proteínas de Unión al ARN/ultraestructura
20.
Arthroscopy ; 40(2): 204-213, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37394149

RESUMEN

PURPOSE: To establish minimal clinically important difference (MCID) and patient acceptable symptomatic state (PASS) values for 4 patient-reported outcomes (PROs) in patients undergoing arthroscopic massive rotator cuff repair (aMRCR): American Shoulder and Elbow Surgeons (ASES) score, Subjective Shoulder Value (SSV), Veterans Rand-12 (VR-12) score, and the visual analog scale (VAS) pain. In addition, our study seeks to determine preoperative factors associated with achieving clinically significant improvement as defined by the MCID and PASS. METHODS: A retrospective review at 2 institutions was performed to identify patients undergoing aMRCR with minimum 4-year follow-up. Data collected at the 1-year, 2-year, and 4-year time points included patient characteristics (age, sex, length of follow-up, tobacco use, and workers' compensation status), radiologic parameters (Goutallier fatty infiltration and modified Collin tear pattern), and 4 PRO measures (collected preoperatively and postoperatively): ASES score, SSV, VR-12 score, and VAS pain. The MCID and PASS for each outcome measure were calculated using the distribution-based method and receiver operating characteristic curve analysis, respectively. Pearson and Spearman coefficient analyses were used to determine correlations between preoperative variables and MCID or PASS thresholds. RESULTS: A total of 101 patients with a mean follow-up of 64 months were included in the study. The MCID and PASS values at the 4-year follow-up for ASES were 14.5 and 69.4, respectively; for SSV, 13.7 and 81.5; for VR-12, 6.6 and 40.3; and for VAS pain, 1.3 and 1.2. Greater infraspinatus fatty infiltration was associated with failing to reach clinically significant values. CONCLUSIONS: This study defined MCID and PASS values for commonly used outcome measures in patients undergoing aMRCR at the 1-year, 2-year, and 4-year follow-up. At mid-term follow-up, greater preoperative rotator cuff disease severity was associated with failure to achieve clinically significant outcomes. LEVEL OF EVIDENCE: Level IV, case series.


Asunto(s)
Satisfacción del Paciente , Lesiones del Manguito de los Rotadores , Humanos , Manguito de los Rotadores/cirugía , Resultado del Tratamiento , Artroscopía , Estudios Retrospectivos , Medición de Resultados Informados por el Paciente , Dolor , Lesiones del Manguito de los Rotadores/cirugía
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