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1.
Science ; 385(6710): 752-756, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39146402

RESUMEN

An impact at Chicxulub, Mexico, occurred 66 million years ago, producing a global stratigraphic layer that marks the boundary between the Cretaceous and Paleogene eras. That layer contains elevated concentrations of platinum-group elements, including ruthenium. We measured ruthenium isotopes in samples taken from three Cretaceous-Paleogene boundary sites, five other impacts that occurred between 36 million to 470 million years ago, and ancient 3.5-billion- to 3.2-billion-year-old impact spherule layers. Our data indicate that the Chicxulub impactor was a carbonaceous-type asteroid, which had formed beyond the orbit of Jupiter. The five other impact structures have isotopic signatures that are more consistent with siliceous-type asteroids, which formed closer to the Sun. The ancient spherule layer samples are consistent with impacts of carbonaceous-type asteroids during Earth's final stages of accretion.

2.
Transl Psychiatry ; 14(1): 296, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39025838

RESUMEN

Cytochrome P450 enzymes including CYP2C19 and CYP2D6 are important for antidepressant metabolism and polymorphisms of these genes have been determined to predict metabolite levels. Nonetheless, more evidence is needed to understand the impact of genetic variations on antidepressant response. In this study, individual clinical and genetic data from 13 studies of European and East Asian ancestry populations were collected. The antidepressant response was clinically assessed as remission and percentage improvement. Imputed genotype was used to translate genetic polymorphisms to metabolic phenotypes (poor, intermediate, normal, and rapid+ultrarapid) of CYP2C19 and CYP2D6. CYP2D6 structural variants cannot be imputed from genotype data, limiting the determination of metabolic phenotypes, and precluding testing for association with response. The association of CYP2C19 metabolic phenotypes with treatment response was examined using normal metabolizers as the reference. Among 5843 depression patients, a higher remission rate was found in CYP2C19 poor metabolizers compared to normal metabolizers at nominal significance but did not survive after multiple testing correction (OR = 1.46, 95% CI [1.03, 2.06], p = 0.033, heterogeneity I2 = 0%, subgroup difference p = 0.72). No metabolic phenotype was associated with percentage improvement from baseline. After stratifying by antidepressants primarily metabolized by CYP2C19, no association was found between metabolic phenotypes and antidepressant response. Metabolic phenotypes showed differences in frequency, but not effect, between European- and East Asian-ancestry studies. In conclusion, metabolic phenotypes imputed from genetic variants using genotype were not associated with antidepressant response. CYP2C19 poor metabolizers could potentially contribute to antidepressant efficacy with more evidence needed. Sequencing and targeted pharmacogenetic testing, alongside information on side effects, antidepressant dosage, depression measures, and diverse ancestry studies, would more fully capture the influence of metabolic phenotypes.


Asunto(s)
Antidepresivos , Citocromo P-450 CYP2C19 , Citocromo P-450 CYP2D6 , Femenino , Humanos , Masculino , Antidepresivos/uso terapéutico , Pueblo Asiatico/genética , Citocromo P-450 CYP2C19/genética , Citocromo P-450 CYP2D6/genética , Citocromo P-450 CYP2D6/metabolismo , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/genética , Trastorno Depresivo Mayor/metabolismo , Genotipo , Fenotipo , Resultado del Tratamiento , Población Blanca/genética
3.
J Nat Prod ; 87(7): 1860-1871, 2024 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-39012621

RESUMEN

A chemical investigation of Laburnicola nematophila, isolated from cysts of the plant parasitic nematode Heterodera filipjevi, affored three dactylfungin derivatives (1-3) and three tetralone congeners (4-6). Dactylfungin C (1), laburnicolin (4), and laburnicolenone (5) are previously undescribed natural products. Chemical structures of the isolated compounds were determined based on 1D and 2D NMR spectroscopic analyses together with HR-ESI-MS spectrometry and comparison with data reported in the literature. The relative configurations of compounds 1, 2, and 4-6 were determined based on their ROESY data and analysis of their coupling constants (J values). The absolute configurations of 4-6 were determined through the comparison of their measured and calculated TDDFT-ECD spectra. Compounds 1-3 were active against azole-resistant Aspergillus fumigatus.


Asunto(s)
Tetralonas , Animales , Estructura Molecular , Tetralonas/farmacología , Tetralonas/química , Antifúngicos/farmacología , Antifúngicos/química , Pruebas de Sensibilidad Microbiana , Tylenchoidea/efectos de los fármacos
4.
Int J Mol Sci ; 25(11)2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38892316

RESUMEN

The microbiome of the ocular surface has been characterised, but only limited information is available on a possible silent intraocular microbial colonisation in normal eyes. Therefore, we performed next-generation sequencing (NGS) of 16S rDNA genes in the aqueous humour. The aqueous humour was sampled from three patients during cataract surgery. Air swabs, conjunctival swabs from patients as well as from healthy donors served as controls. Following DNA extraction, the V3 and V4 hypervariable regions of the 16S rDNA gene were amplified and sequenced followed by denoising. The resulting Amplicon Sequence Variants were matched to a subset of the Ribosomal Database Project 16S database. The deduced bacterial community was then statistically analysed. The DNA content in all samples was low (0-1.49 ng/µL) but sufficient for analysis. The main phyla in the samples were Acinetobacteria (48%), Proteobacteria (26%), Firmicutes (14%), Acidobacteria (8%), and Bacteroidetes (2%). Patients' conjunctival control samples and anterior chamber fluid showed similar patterns of bacterial species containing many waterborne species. Non-disinfected samples showed a different bacterial spectrum than the air swab samples. The data confirm the existence of an ocular surface microbiome. Meanwhile, a distinct intraocular microbiome was not discernible from the background, suggesting the absence of an intraocular microbiome in normal eyes.


Asunto(s)
Humor Acuoso , Bacterias , Secuenciación de Nucleótidos de Alto Rendimiento , Microbiota , ARN Ribosómico 16S , Humanos , Humor Acuoso/microbiología , Microbiota/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , ARN Ribosómico 16S/genética , Bacterias/genética , Bacterias/clasificación , Bacterias/aislamiento & purificación , ADN Bacteriano/genética , Masculino , Femenino , Anciano , Persona de Mediana Edad , Análisis de Secuencia de ADN/métodos
5.
Front Psychiatry ; 15: 1367225, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919640

RESUMEN

Purpose: The present study aimed to investigate age-group-specific incidence rates and risk factors for depressive symptoms in the highest age groups. Methods: Data were derived from a prospective multicenter cohort study conducted in primary care - the AgeCoDe/AgeQualiDe study. In total, 2,436 patients 75 years and older were followed from baseline to ninth follow-up. To assess depressive symptoms, the short version of the Geriatric Depression Scale (GDS-15, cutoff score 6) was used. Age-specific competing risk regressions were performed to analyze risk factors for incident depressive symptoms in different age groups (75 to 79, 80 to 84, 85+ years), taking into account the accumulated mortality. Results: The age-specific incidence rate of depression was 33 (95% CI 29-38), 46 (95% CI 40-52) and 63 (95% CI 45-87) per 1,000 person years for the initial age groups 75 to 79, 80 to 84 and 85+ years, respectively. In competing risk regression models, female sex, mobility as well as vision impairment, and subjective cognitive decline (SCD) were found to be risk factors for incident depression for age group 75 to 79, female sex, single/separated marital status, mobility as well as hearing impairment, and SCD for age group 80 to 84, and mobility impairment for age group 85+. Conclusion: Depressive symptoms in latest life are common and the incidence increases with increasing age. Modifiable and differing risk factors across the highest age groups open up the possibility of specifically tailored prevention concepts.

6.
ACS Omega ; 9(19): 21658-21667, 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38764662

RESUMEN

Nematode-associated fungi revealed the potential to produce a broad spectrum of chemical scaffolds. In this study, a mycelial extract of Laburnicola nematophila, a fungal strain derived from the cereal cyst nematode Heterodera filipjevi, was chemically explored and afforded six unprecedentedly reported acylic N-acetyl oligopeptides, laburnicotides A-F (1-6). Structure elucidation of the isolated compounds was established based on comprehensive 1D and 2D NMR spectroscopic analyses together with the acquired HR-ESI-MS spectrometric data. The absolute configuration of amino acid residues in 1-6 was established by performing advanced Marfey's derivatization method. All isolated compounds were assessed for their cytotoxic, antimicrobial, antiviral, and nematicidal activities with no potential activity observed.

7.
Chem Biodivers ; 21(8): e202401152, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38771298

RESUMEN

A chemical investigation of a methanol extract derived from a solid-state rice culture of the nematode-cyst associated fungus Laburnicola nematophila K01 led to the isolation and characterization of a previously undescribed penillic acid analogue named laburnicolamine (1). The chemical structure was elucidated through comprehensive 1D and 2D NMR spectroscopic analyses in methanol-d4 and DMSO-d6, alongside with HR-ESI-MS spectrometry. The absolute configuration of 1 was concluded through the electronic circular dichroism (ECD) and time-dependent density functional theory-ECD (TDDFT-ECD) computations compared to its acquired spectrum. Biological assays revealed that compound 1 exhibited no significant cytotoxic, antimicrobial, or nematicidal activity.


Asunto(s)
Pruebas de Sensibilidad Microbiana , Animales , Humanos , Teoría Funcional de la Densidad , Nematodos/efectos de los fármacos , Conformación Molecular , Estructura Molecular , Hypocreales/química
8.
J Agric Food Chem ; 72(13): 6998-7009, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38507729

RESUMEN

Chemical exploration for two isolates of the recently described ascomycete species Polyphilus sieberi, derived from the eggs of the plant parasitic nematode Heterodera filipjevi, afforded the identification of many compounds that belong to various metabolite families: two previously undescribed chlorinated cyclotetrapeptides, omnipolyphilins A (1) and B (2), one new pyranonaphthoquinone, ventiloquinone P (3), a 6,6'-binaphto-α-pyranone dimer, talaroderxine D (4) in addition to nine known metabolites (5-13) were isolated from this biocontrol candidate. All isolated compounds were characterized by comprehensive 1D, 2D NMR, and HR-ESI-MS analyses. The absolute configurations of the cyclotetrapeptides were determined by a combination of advanced Marfey's method, ROE correlation aided by conformational analysis, and TDDFT-ECD calculations, while ECD calculations, Mosher's method, and experimental ECD spectra were used for ventiloquinone P (3) and talaroderxine D (4). Among the isolated compounds, talaroderxine D (4) showed potent antimicrobial activities against Bacillus subtilis and Staphylococcus aureus with MIC values of 2.1 and 8.3 µg mL-1, respectively. Additionally, promising inhibitory effects on talaroderxine D (4) against the formation of S. aureus biofilms were observed up to a concentration of 0.25 µg mL-1. Moreover, ophiocordylongiiside A (10) showed activity against the free-living nematode Caenorhabditis elegans.


Asunto(s)
Ascomicetos , Tylenchoidea , Humanos , Animales , Staphylococcus aureus , Bacillus subtilis , Estructura Molecular
9.
Viruses ; 16(3)2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38543795

RESUMEN

Genomic sequencing of clinical samples to identify emerging variants of SARS-CoV-2 has been a key public health tool for curbing the spread of the virus. As a result, an unprecedented number of SARS-CoV-2 genomes were sequenced during the COVID-19 pandemic, which allowed for rapid identification of genetic variants, enabling the timely design and testing of therapies and deployment of new vaccine formulations to combat the new variants. However, despite the technological advances of deep sequencing, the analysis of the raw sequence data generated globally is neither standardized nor consistent, leading to vastly disparate sequences that may impact identification of variants. Here, we show that for both Illumina and Oxford Nanopore sequencing platforms, downstream bioinformatic protocols used by industry, government, and academic groups resulted in different virus sequences from same sample. These bioinformatic workflows produced consensus genomes with differences in single nucleotide polymorphisms, inclusion and exclusion of insertions, and/or deletions, despite using the same raw sequence as input datasets. Here, we compared and characterized such discrepancies and propose a specific suite of parameters and protocols that should be adopted across the field. Consistent results from bioinformatic workflows are fundamental to SARS-CoV-2 and future pathogen surveillance efforts, including pandemic preparation, to allow for a data-driven and timely public health response.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiología , Pandemias , Flujo de Trabajo , Biología Computacional
10.
Microb Genom ; 10(2)2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38358325

RESUMEN

The COVID-19 pandemic has seen large-scale pathogen genomic sequencing efforts, becoming part of the toolbox for surveillance and epidemic research. This resulted in an unprecedented level of data sharing to open repositories, which has actively supported the identification of SARS-CoV-2 structure, molecular interactions, mutations and variants, and facilitated vaccine development and drug reuse studies and design. The European COVID-19 Data Platform was launched to support this data sharing, and has resulted in the deposition of several million SARS-CoV-2 raw reads. In this paper we describe (1) open data sharing, (2) tools for submission, analysis, visualisation and data claiming (e.g. ORCiD), (3) the systematic analysis of these datasets, at scale via the SARS-CoV-2 Data Hubs as well as (4) lessons learnt. This paper describes a component of the Platform, the SARS-CoV-2 Data Hubs, which enable the extension and set up of infrastructure that we intend to use more widely in the future for pathogen surveillance and pandemic preparedness.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Pandemias , COVID-19/epidemiología , Genómica , Difusión de la Información
11.
J Affect Disord ; 350: 618-626, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38244789

RESUMEN

BACKGROUND: Unmet care needs have been associated with an increased risk of depression in old age. Currently, the identification of profiles of met and unmet care needs associated with depressive symptoms is pending. Therefore, this exploratory study aimed to identify profiles of care needs and analyze associated factors in oldest-old patients with and without depression. METHODS: The sample of 1092 GP patients aged 75+ years is based on the multicenter study "Late-life depression in primary care: needs, health care utilization and costs (AgeMooDe)". Depression (i.e. clinically meaningful depressive symptoms) was determined using the Geriatric Depression Scale (GDS) (cutoff score ≥ 4). Needs of patients were assessed using the Camberwell Assessment of Need for the Elderly (CANE). Associated sociodemographic and clinical factors were examined, and latent class analysis identified the need profiles. RESULTS: The main result of the study indicates three need profiles: 'no needs', 'met physical needs', and 'unmet social needs'. Members of the 'met physical needs' (OR = 3.5, 95 %-CI: 2.5-4.9) and 'unmet social needs' (OR = 17.4, 95 %-CI: 7.7-39.7) profiles were significantly more likely to have depression compared to members of the 'no needs' profile. LIMITATIONS: Based on the cross-sectional design, no conclusions can be drawn about the causality or direction of the relationships between the variables. CONCLUSIONS: The study results provide important insights for the establishment of needs-based interventions for GPs. Particular attention should be paid to the presence of unmet social needs in the oldest-old GP patients with underlying depressive symptoms.


Asunto(s)
Depresión , Necesidades y Demandas de Servicios de Salud , Anciano , Anciano de 80 o más Años , Humanos , Estudios Transversales , Depresión/epidemiología , Depresión/diagnóstico , Evaluación de Necesidades , Atención Primaria de Salud/métodos , Estudios Multicéntricos como Asunto
12.
J Cell Sci ; 137(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-37667859

RESUMEN

Ciliates assemble numerous microtubular structures into complex cortical patterns. During ciliate division, the pattern is duplicated by intracellular segmentation that produces a tandem of daughter cells. In Tetrahymena thermophila, the induction and positioning of the division boundary involves two mutually antagonistic factors: posterior CdaA (cyclin E) and anterior CdaI (Hippo kinase). Here, we characterized the related cdaH-1 allele, which confers a pleiotropic patterning phenotype including an absence of the division boundary and an anterior-posterior mispositioning of the new oral apparatus. CdaH is a Fused or Stk36 kinase ortholog that localizes to multiple sites that correlate with the effects of its loss, including the division boundary and the new oral apparatus. CdaH acts downstream of CdaA to induce the division boundary and drives asymmetric cytokinesis at the tip of the posterior daughter. CdaH both maintains the anterior-posterior position of the new oral apparatus and interacts with CdaI to pattern ciliary rows within the oral apparatus. Thus, CdaH acts at multiple scales, from induction and positioning of structures on the cell-wide polarity axis to local organelle-level patterning.


Asunto(s)
Tetrahymena thermophila , Tetrahymena , Tetrahymena/genética , División Celular/genética , Acetamidas , Tetrahymena thermophila/genética , Citoesqueleto
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