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1.
Nature ; 622(7983): 537-544, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37758942

RESUMO

Climate's effect on global biodiversity is typically viewed through the lens of temperature, humidity and resulting ecosystem productivity1-6. However, it is not known whether biodiversity depends solely on these climate conditions, or whether the size and fragmentation of these climates are also crucial. Here we shift the common perspective in global biodiversity studies, transitioning from geographic space to a climate-defined multidimensional space. Our findings suggest that larger and more isolated climate conditions tend to harbour higher diversity and species turnover among terrestrial tetrapods, encompassing more than 30,000 species. By considering both the characteristics of climate itself and its geographic attributes, we can explain almost 90% of the variation in global species richness. Half of the explanatory power (45%) may be attributed either to climate itself or to the geography of climate, suggesting a nuanced interplay between them. Our work evolves the conventional idea that larger climate regions, such as the tropics, host more species primarily because of their size7,8. Instead, we underscore the integral roles of both the geographic extent and degree of isolation of climates. This refined understanding presents a more intricate picture of biodiversity distribution, which can guide our approach to biodiversity conservation in an ever-changing world.


Assuntos
Biodiversidade , Clima , Geografia , Animais , Conservação dos Recursos Naturais/métodos , Mapeamento Geográfico , Umidade , Temperatura , Clima Tropical
2.
Am J Hum Genet ; 111(8): 1524-1543, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39053458

RESUMO

Gene misexpression is the aberrant transcription of a gene in a context where it is usually inactive. Despite its known pathological consequences in specific rare diseases, we have a limited understanding of its wider prevalence and mechanisms in humans. To address this, we analyzed gene misexpression in 4,568 whole-blood bulk RNA sequencing samples from INTERVAL study blood donors. We found that while individual misexpression events occur rarely, in aggregate they were found in almost all samples and a third of inactive protein-coding genes. Using 2,821 paired whole-genome and RNA sequencing samples, we identified that misexpression events are enriched in cis for rare structural variants. We established putative mechanisms through which a subset of SVs lead to gene misexpression, including transcriptional readthrough, transcript fusions, and gene inversion. Overall, we develop misexpression as a type of transcriptomic outlier analysis and extend our understanding of the variety of mechanisms by which genetic variants can influence gene expression.


Assuntos
Regulação da Expressão Gênica , Humanos , Análise de Sequência de RNA , Variação Genética , Variação Estrutural do Genoma/genética , Transcriptoma/genética , Doadores de Sangue
3.
Nature ; 592(7853): 277-282, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33545711

RESUMO

The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for virus infection through the engagement of the human ACE2 protein1 and is a major antibody target. Here we show that chronic infection with SARS-CoV-2 leads to viral evolution and reduced sensitivity to neutralizing antibodies in an immunosuppressed individual treated with convalescent plasma, by generating whole-genome ultra-deep sequences for 23 time points that span 101 days and using in vitro techniques to characterize the mutations revealed by sequencing. There was little change in the overall structure of the viral population after two courses of remdesivir during the first 57 days. However, after convalescent plasma therapy, we observed large, dynamic shifts in the viral population, with the emergence of a dominant viral strain that contained a substitution (D796H) in the S2 subunit and a deletion (ΔH69/ΔV70) in the S1 N-terminal domain of the spike protein. As passively transferred serum antibodies diminished, viruses with the escape genotype were reduced in frequency, before returning during a final, unsuccessful course of convalescent plasma treatment. In vitro, the spike double mutant bearing both ΔH69/ΔV70 and D796H conferred modestly decreased sensitivity to convalescent plasma, while maintaining infectivity levels that were similar to the wild-type virus.The spike substitution mutant D796H appeared to be the main contributor to the decreased susceptibility to neutralizing antibodies, but this mutation resulted in an infectivity defect. The spike deletion mutant ΔH69/ΔV70 had a twofold higher level of infectivity than wild-type SARS-CoV-2, possibly compensating for the reduced infectivity of the D796H mutation. These data reveal strong selection on SARS-CoV-2 during convalescent plasma therapy, which is associated with the emergence of viral variants that show evidence of reduced susceptibility to neutralizing antibodies in immunosuppressed individuals.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19/terapia , COVID-19/virologia , Evolução Molecular , Mutagênese/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Monofosfato de Adenosina/uso terapêutico , Idoso , Alanina/análogos & derivados , Alanina/farmacologia , Alanina/uso terapêutico , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Doença Crônica , Genoma Viral/efeitos dos fármacos , Genoma Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Evasão da Resposta Imune/efeitos dos fármacos , Evasão da Resposta Imune/genética , Evasão da Resposta Imune/imunologia , Tolerância Imunológica/efeitos dos fármacos , Tolerância Imunológica/imunologia , Imunização Passiva , Terapia de Imunossupressão , Masculino , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/imunologia , Mutação , Filogenia , SARS-CoV-2/imunologia , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Fatores de Tempo , Carga Viral/efeitos dos fármacos , Eliminação de Partículas Virais , Soroterapia para COVID-19
4.
Proc Natl Acad Sci U S A ; 121(13): e2320053121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38513100

RESUMO

Lysosome-targeting chimeras (LYTACs) are a promising therapeutic modality to drive the degradation of extracellular proteins. However, early versions of LYTAC contain synthetic glycopeptides that cannot be genetically encoded. Here, we present our designs for a fully genetically encodable LYTAC (GELYTAC), making our tool compatible with integration into therapeutic cells for targeted delivery at diseased sites. To achieve this, we replaced the glycopeptide portion of LYTACs with the protein insulin-like growth factor 2 (IGF2). After showing initial efficacy with wild-type IGF2, we increased the potency of GELYTAC using directed evolution. Subsequently, we demonstrated that our engineered GELYTAC construct not only secretes from HEK293T cells but also from human primary T-cells to drive the uptake of various targets into receiver cells. Immune cells engineered to secrete GELYTAC thus represent a promising avenue for spatially selective targeted protein degradation.


Assuntos
Lisossomos , Humanos , Células HEK293 , Proteólise
5.
Semin Cell Dev Biol ; 155(Pt B): 22-31, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-37258315

RESUMO

Thrombospondin-1 is a secreted matricellular glycoprotein that modulates cell behavior by interacting with components of the extracellular matrix and with several cell surface receptors. Its presence in the extracellular matrix is induced by injuries that cause thrombospondin-1 release from platelets and conditions including hyperglycemia, ischemia, and aging that stimulate its expression by many cell types. Conversely, rapid receptor-mediated clearance of thrombospondin-1 from the extracellular space limits its sustained presence in the extracellular space and maintains sub-nanomolar physiological concentrations in blood plasma. Roles for thrombospondin-1 signaling, mediated by specific cellular receptors or by activation of latent TGFß, have been defined in T and B lymphocytes, natural killer cells, macrophages, neutrophils, and dendritic cells. In addition to regulating physiological nitric oxide signaling and responses of cells to stress, studies in mice lacking thrombospondin-1 or its receptors have revealed important roles for thrombospondin-1 in regulating immune responses in infectious and autoimmune diseases and antitumor immunity.


Assuntos
Antígeno CD47 , Transdução de Sinais , Animais , Camundongos , Antígeno CD47/metabolismo , Transdução de Sinais/fisiologia , Matriz Extracelular/metabolismo , Trombospondinas
6.
Proc Natl Acad Sci U S A ; 120(19): e2222081120, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37126723

RESUMO

Single-cell proteomics has emerged as a powerful method to characterize cellular phenotypic heterogeneity and the cell-specific functional networks underlying biological processes. However, significant challenges remain in single-cell proteomics for the analysis of proteoforms arising from genetic mutations, alternative splicing, and post-translational modifications. Herein, we have developed a highly sensitive functionally integrated top-down proteomics method for the comprehensive analysis of proteoforms from single cells. We applied this method to single muscle fibers (SMFs) to resolve their heterogeneous functional and proteomic properties at the single-cell level. Notably, we have detected single-cell heterogeneity in large proteoforms (>200 kDa) from the SMFs. Using SMFs obtained from three functionally distinct muscles, we found fiber-to-fiber heterogeneity among the sarcomeric proteoforms which can be related to the functional heterogeneity. Importantly, we detected multiple isoforms of myosin heavy chain (~223 kDa), a motor protein that drives muscle contraction, with high reproducibility to enable the classification of individual fiber types. This study reveals single muscle cell heterogeneity in large proteoforms and establishes a direct relationship between sarcomeric proteoforms and muscle fiber types, highlighting the potential of top-down proteomics for uncovering the molecular underpinnings of cell-to-cell variation in complex systems.


Assuntos
Processamento de Proteína Pós-Traducional , Proteômica , Proteômica/métodos , Reprodutibilidade dos Testes , Isoformas de Proteínas/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Proteoma/metabolismo
7.
Am J Hum Genet ; 109(6): 1038-1054, 2022 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-35568032

RESUMO

Metabolite levels measured in the human population are endophenotypes for biological processes. We combined sequencing data for 3,924 (whole-exome sequencing, WES, discovery) and 2,805 (whole-genome sequencing, WGS, replication) donors from a prospective cohort of blood donors in England. We used multiple approaches to select and aggregate rare genetic variants (minor allele frequency [MAF] < 0.1%) in protein-coding regions and tested their associations with 995 metabolites measured in plasma by using ultra-high-performance liquid chromatography-tandem mass spectrometry. We identified 40 novel associations implicating rare coding variants (27 genes and 38 metabolites), of which 28 (15 genes and 28 metabolites) were replicated. We developed algorithms to prioritize putative driver variants at each locus and used mediation and Mendelian randomization analyses to test directionality at associations of metabolite and protein levels at the ACY1 locus. Overall, 66% of reported associations implicate gene targets of approved drugs or bioactive drug-like compounds, contributing to drug targets' validating efforts.


Assuntos
Exoma , Exoma/genética , Frequência do Gene/genética , Humanos , Estudos Prospectivos , Sequenciamento do Exoma/métodos , Sequenciamento Completo do Genoma
8.
Proc Natl Acad Sci U S A ; 119(41): e2204042119, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36206370

RESUMO

SMC complexes, loaded at ParB-parS sites, are key mediators of chromosome organization in bacteria. ParA/Soj proteins interact with ParB/Spo0J in a pathway involving adenosine triphosphate (ATP)-dependent dimerization and DNA binding, facilitating chromosome segregation in bacteria. In Bacillus subtilis, ParA/Soj also regulates DNA replication initiation and along with ParB/Spo0J is involved in cell cycle changes during endospore formation. The first morphological stage in sporulation is the formation of an elongated chromosome structure called an axial filament. Here, we show that a major redistribution of SMC complexes drives axial filament formation in a process regulated by ParA/Soj. Furthermore, and unexpectedly, this regulation is dependent on monomeric forms of ParA/Soj that cannot bind DNA or hydrolyze ATP. These results reveal additional roles for ParA/Soj proteins in the regulation of SMC dynamics in bacteria and yet further complexity in the web of interactions involving chromosome replication, segregation and organization, controlled by ParAB and SMC.


Assuntos
Bacillus subtilis , Cromossomos Bacterianos , Adenosina Trifosfatases , Trifosfato de Adenosina/metabolismo , Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Segregação de Cromossomos , Cromossomos Bacterianos/genética , Cromossomos Bacterianos/metabolismo , DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Complexos Multiproteicos
9.
Glycobiology ; 34(1)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-37815932

RESUMO

Galectin-3, well characterized as a glycan binding protein, has been identified as a putative RNA binding protein, possibly through participation in pre-mRNA maturation through interactions with splicosomes. Given recent developments with cell surface RNA biology, the putative dual-function nature of galectin-3 evokes a possible non-classical connection between glycobiology and RNA biology. However, with limited functional evidence of a direct RNA interaction, many molecular-level observations rely on affinity reagents and lack appropriate genetic controls. Thus, evidence of a direct interaction remains elusive. We demonstrate that antibodies raised to endogenous human galectin-3 can isolate RNA-protein crosslinks, but this activity remains insensitive to LGALS3 knock-out. Proteomic characterization of anti-galectin-3 IPs revealed enrichment of galectin-3, but high abundance of hnRNPA2B1, an abundant, well-characterized RNA-binding protein with weak homology to the N-terminal domain of galectin-3, in the isolate. Genetic ablation of HNRNPA2B1, but not LGALS3, eliminates the ability of the anti-galectin-3 antibodies to isolate RNA-protein crosslinks, implying either an indirect interaction or cross-reactivity. To address this, we introduced an epitope tag to the endogenous C-terminal locus of LGALS3. Isolation of the tagged galectin-3 failed to reveal any RNA-protein crosslinks. This result suggests that the galectin-3 does not directly interact with RNA and may be misidentified as an RNA-binding protein, at least in HeLa where the putative RNA associations were first identified. We encourage further investigation of this phenomenon employ gene deletions and, when possible, endogenous epitope tags to achieve the specificity required to evaluate potential interactions.


Assuntos
Galectina 3 , RNA , Humanos , Epitopos , Galectina 3/genética , Galectina 3/metabolismo , Galectinas/metabolismo , Proteômica , Proteínas de Ligação a RNA
10.
Mol Biol Evol ; 40(9)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37671664

RESUMO

Nonadaptive hypotheses on the evolution of eukaryotic genome size predict an expansion when the process of purifying selection becomes weak. Accordingly, species with huge genomes, such as lungfish, are expected to show a genome-wide relaxation signature of selection compared with other organisms. However, few studies have empirically tested this prediction using genomic data in a comparative framework. Here, we show that 1) the newly assembled transcriptome of the Australian lungfish, Neoceratodus forsteri, is characterized by an excess of pervasive transcription, or transcriptional leakage, possibly due to suboptimal transcriptional control, and 2) a significant relaxation signature in coding genes in lungfish species compared with other vertebrates. Based on these observations, we propose that the largest known animal genomes evolved in a nearly neutral scenario where genome expansion is less efficiently constrained.


Assuntos
Peixes , Genômica , Animais , Austrália , Peixes/genética , Tamanho do Genoma , Seleção Genética
11.
Kidney Int ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39181398

RESUMO

Human leukocyte antigen (HLA) sensitization remains an impediment to successful solid organ transplantation, whether it be chances of receiving a transplant offer or subsequent transplant longevity. Current treatments targeting HLA antibodies lack long-term effectiveness; therefore, preventing HLA sensitization should remain a priority in all potential wait-list candidates and transplant recipients. Recent advances in the management of anemia in patients with chronic kidney disease may reduce the need for red cell transfusions. However, data from several anemia intervention studies of novel therapeutic agents have shown that a need for transfusion will remain. It has also been increasingly recognized that blood transfusions following kidney transplantation, especially in the peri-operative period, are common. Routine data on transfusion incidence, indications, and outcomes are not captured by most kidney and transplant registries across the globe. This restricts the evidence to inform both clinicians and patients on the clinical effects of transfusion, which have been considered both an allogeneic stimulus and to be immunomodulatory.This review aims to provide an update on what is currently known about transfusion-induced HLA sensitization in wait-list candidates and transplant recipients, summarizes where evidence is lacking, and demonstrates the distinct need for patient blood management guidelines in the field of kidney transplantation.

12.
Eur J Immunol ; 53(9): e2250355, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36991561

RESUMO

The lymph node (LN) is home to resident macrophage populations that are essential for immune function and homeostasis, but key factors controlling this niche are undefined. Here, we show that fibroblastic reticular cells (FRCs) are an essential component of the LN macrophage niche. Genetic ablation of FRCs caused rapid loss of macrophages and monocytes from LNs across two in vivo models. Macrophages co-localized with FRCs in human LNs, and murine single-cell RNA-sequencing revealed that FRC subsets broadly expressed master macrophage regulator CSF1. Functional assays containing purified FRCs and monocytes showed that CSF1R signaling was sufficient to support macrophage development. These effects were conserved between mouse and human systems. These data indicate an important role for FRCs in maintaining the LN parenchymal macrophage niche.


Assuntos
Fibroblastos , Transdução de Sinais , Camundongos , Humanos , Animais , Macrófagos , Linfonodos
13.
Artigo em Inglês | MEDLINE | ID: mdl-39225016

RESUMO

BACKGROUND: Despite improvements in treatment and oral pre-exposure prophylaxis (PrEP) access, 1.3 million people acquired HIV in 2022. Six-monthly lenacapavir PrEP could benefit tens of millions of people at high risk of infection. However, prices are currently up to $44 819 per person per year (pppy). OBJECTIVES: We projected minimum lenacapavir pricing based on generic mass production and a Cost-Plus (Cost+) model. METHODS: Current active pharmaceutical ingredient (API) and key starting materials (KSMs) costs were obtained from export databases. The routes of synthesis (ROS) were analysed to project a cost of goods (COGs). Formulation, vials and profit margin costs were included using standardized algorithms and Cost+ pricing. We estimated prices with scale-up to supply 1 million then 10 million treatment-years, comparing this with national list prices. RESULTS: The lenacapavir API is currently exported from India for $64 480/kg on 1 kg scale. Based on the ROS and KSMs, API COGs of $25 000/kg and $10 000/kg are achievable for a committed demand of 1 million (2 million tonnes/annum of API) and 10 million treatment-years, respectively. Including formulation steps, injectable lenacapavir could be mass produced for approximately $94 pppy for 1 million and $41 for 10 million treatment-years, if voluntary licences are in place and competition between generic suppliers substantially improves. Greater scale-up with improvements in manufacturers' ROS could reduce prices further. Currently lenacapavir costs $25 395-44 819 pppy. CONCLUSIONS: Lenacapavir could be mass produced for <$100 pppy at launch. Voluntary licensing and multiple suppliers are required to achieve these low prices. This mechanism is already in place for other antiretrovirals. To date, Gilead has not agreed lenacapavir voluntary licences with the Medicines Patent Pool.

14.
Bioinformatics ; 39(6)2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37294807

RESUMO

MOTIVATION: Native top-down proteomics (nTDP) integrates native mass spectrometry (nMS) with top-down proteomics (TDP) to provide comprehensive analysis of protein complexes together with proteoform identification and characterization. Despite significant advances in nMS and TDP software developments, a unified and user-friendly software package for analysis of nTDP data remains lacking. RESULTS: We have developed MASH Native to provide a unified solution for nTDP to process complex datasets with database searching capabilities in a user-friendly interface. MASH Native supports various data formats and incorporates multiple options for deconvolution, database searching, and spectral summing to provide a "one-stop shop" for characterizing both native protein complexes and proteoforms. AVAILABILITY AND IMPLEMENTATION: The MASH Native app, video tutorials, written tutorials, and additional documentation are freely available for download at https://labs.wisc.edu/gelab/MASH_Explorer/MASHSoftware.php. All data files shown in user tutorials are included with the MASH Native software in the download .zip file.


Assuntos
Proteômica , Software , Bases de Dados Factuais , Proteínas de Ligação a DNA , Espectrometria de Massas , Proteômica/métodos
15.
Mol Ecol ; 33(5): e17266, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38240411

RESUMO

The Australian lungfish is a primitive and endangered representative of the subclass Dipnoi. The distribution of this species is limited to south-east Queensland, with some populations considered endemic and others possibly descending from translocations in the late nineteenth century shortly after European discovery. Attempts to resolve the historical distribution of this species have met with conflicting results based on descriptive genetic studies. Understanding if all populations are endemic or some are the result of, or influenced by, translocation events, has implications for conservation management. In this work, we analysed the genetic variation at three types of markers (mtDNA genomes, 11 STRs and 5196 nuclear SNPs) using the approximate Bayesian computation (ABC) algorithm to compare several demographic models. We postulated different contributions of Mary River and Burnett River gene pools into the Brisbane River and North Pine River populations, related to documented translocation events. We ran the analysis for each marker type separately, and we also estimated the posterior probabilities of the models combining the markers. Nuclear SNPs have the highest power to correctly identify the true model among the simulated datasets (where the model was known), but different marker types typically provided similar answers. The most supported demographic model able to explain the real dataset implies that an endemic gene pool is still present in the Brisbane and North Pine Rivers and coexists with the gene pools derived from past documented translocation events. These results support the view that ABC modelling can be useful to reconstruct complex historical translocation events with contemporary implications, and will inform ongoing conservation efforts for the endangered and iconic Australian lungfish.


Assuntos
Peixes , Animais , Teorema de Bayes , Austrália , Peixes/genética , Queensland
16.
Chem Res Toxicol ; 37(1): 16-19, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-38079418

RESUMO

The surfactant sodium lauryl sulfate (SLS), although consistently positive in the murine local lymph node assay (LLNA) for skin sensitization, shows no evidence of being a human sensitizer and is often described as a false positive, lacking structural alerts for sensitization. However, there is evidence of the cinnamyl sulfate anion being the metabolite responsible for the sensitization potential of cinnamyl alcohol to humans and in animal tests. Here, manufacturing chemistry data and physical organic chemistry principles are applied to confirm that SLS is not reactive enough to sensitize, whereas sensitization to cinnamyl alcohol via cinnamyl sulfate is plausible. Sensitization data for several other primary alcohols, including geraniol, farnesol, and possibly hydrocortisone, are also consistent with this mechanism. It seems possible that biosulfation may play a wider role than has previously been recognized in skin sensitization.


Assuntos
Álcoois , Dermatite Alérgica de Contato , Humanos , Animais , Camundongos , Álcoois/metabolismo , Sulfatos/metabolismo , Pele/metabolismo , Propanóis/metabolismo , Ensaio Local de Linfonodo , Dermatite Alérgica de Contato/metabolismo , Alérgenos/química
17.
Chem Res Toxicol ; 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39259600

RESUMO

It has long been recognized that skin sensitizers either are electrophilic or can be activated to electrophilic species. Several nonanimal assays for skin sensitization are based on this premise. In the course of a project to update dermal sensitization thresholds (DST), we found a substantial number of sensitizers, with no electrophilic or pro-electrophilic alerts, that could be simply explained in terms of the sensitizer acting as a nucleophile. In some cases, the nucleophilic center is a sulfur or phosphorus atom, while in others, it is an aromatic carbon atom. For carbon-centered nucleophiles, a quantitative mechanistic model based on a combination of Hammett σ+ and logP values has been derived. This has been applied to rationalize several groups of known sensitizers with no electrophilic or pro-electrophilic alerts, including anacardic acids and cardols, which are known human sensitizers associated with, inter alia, cashew nut oil, mango, and Ginkgo biloba. The possibility of nucleophilic sensitization needs to be considered when evaluating new chemicals for skin sensitization potential and potency by nonanimal assays, particularly those based on the premise that skin sensitization is dependent upon reactions of electrophiles with skin protein-based nucleophiles.

18.
Artigo em Inglês | MEDLINE | ID: mdl-39109463

RESUMO

BACKGROUND: In 2019, the US Food and Drug Administration (FDA) approved transcatheter aortic valve replacement (TAVR) for low-risk patients with symptomatic severe tricuspid aortic stenosis. However, bicuspid aortic valve (BAV) patients were included only in single-arm registries of pivotal low-risk TAVR trials, resulting in limited data for this subgroup. METHODS: The LRT (Low Risk TAVR) trial was an investigator-initiated, prospective, multicenter study and the first FDA-approved investigational device exemption trial to evaluate the feasibility of TAVR with balloon-expandable or self-expanding valves in low-risk patients with symptomatic severe BAV stenosis. This analysis reports 2-year follow-up, assessing the primary outcome of all-cause mortality and evaluating clinical outcomes. RESULTS: From 2016 to 2019, a total of 72 low-risk patients diagnosed with symptomatic, severe BAV stenosis underwent TAVR across six centers. Six patients were lost to follow-up. At 2-year follow-up, mortality was 1.5% (1 of 66 patients). Among the remaining 65 patients, four experienced nondisabling strokes (6.2%), while 2 (3.1%) developed infective endocarditis. No new permanent pacemakers were required beyond the 30-day follow-up, and no patients, including those with endocarditis, needed aortic valve re-intervention. At the 2-year echocardiography follow-up (n = 65), 27.8% of BAV patients showed mild aortic regurgitation, with none exhibiting moderate or severe regurgitation. The mean aortic gradient was 12.1 ± 4.1 mmHg, and the mean valve area was 1.7 ± 0.5 cm². CONCLUSION: The 2-year follow-up confirms commendable clinical outcomes of TAVR in patients with bicuspid aortic stenosis, establishing its evident safety.

19.
Pharmacol Res ; 199: 107043, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38128855

RESUMO

In the life sciences, there is an ongoing discussion about a perceived 'reproducibility crisis'. However, it remains unclear to which extent the perceived lack of reproducibility is the consequence of issues that can be tackled and to which extent it may be the consequence of unrealistic expectations of the technical level of reproducibility. Large-scale, multi-institutional experimental replication studies are very cost- and time-intensive. This Perspective suggests an alternative, complementary approach: meta-research using sociological and philosophical methodologies to examine researcher trust in data. An improved understanding of the criteria used by researchers to judge data reliability will provide crucial, initial evidence on the actual scale of the reproducibility crisis and on measures to tackle it.


Assuntos
Confiança , Reprodutibilidade dos Testes , Humanos
20.
Conserv Biol ; 38(5): e14361, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39248746

RESUMO

Due diligence is a fundamental component of ensuring a sustainable and legal wildlife trade that is also supportive of the livelihoods and businesses that depend on the trade. This is particularly true with species listed on the Convention on International Trade in Endangered Species (CITES) that are considered threatened or may become threatened by trade. Undertaking due diligence exercises requires access to information on which to base such decisions; however, the extent to which information is available is unclear. We used the trade in tropical pitcher plants (Nepenthes) for horticultural purposes as a case study to determine the extent to which information is available. A systematic survey of online trade was conducted for species described from 1996 to 2016. For the species found in trade, these were cross-referenced with the CITES trade database, and inquiries were made to the relevant CITES Management Authorities and National Focal Points Access and Benefit Sharing (ABS). Of 83 newly described species, 61% were offered for sale online in 2018. Despite all Nepenthes species being listed on CITES, only 23% (n = 19) of the species being sold online were reported in trade on the CITES Trade Database, and only 3 were from the countries of origin. Thirty-two of these species had no international trade recorded according to the database. Management authorities of CITES for the countries of origin confirmed trade had been permitted for 5 of 32 species. Lack of CITES records may be explained by trade under "Nepenthes spp." or as exempt parts and derivatives. However, permits to collect and commercialize are likely to be required as part of the Nagoya Protocol on ABS from the Convention on Biological Diversity. The ABS National Focal Points were contacted to determine whether collection or commercialization permits had been issued for the remaining species. Only 2 of 7 focal points replied, and both stated no permits had been issued. Lack of traceability information or response related to the issuance of collection and commercialization permits is concerning and hinders the due diligence of businesses and consumers wanting to ensure their trade is legal, sustainable, and ethical.


Definición de la legalidad de especies recién catalogadas en CITES en la horticultura comercial de plantas de jarra tropicales (Nepenthes) Resumen La diligencia debida es un componente fundamental para garantizar un comercio de vida silvestre legal y sostenible que también apoye los medios de subsistencia y las empresas que dependen del comercio. Esto es especialmente cierto en el caso de las especies incluidas en la Convención sobre el Comercio Internacional de Especies Amenazadas de Fauna y Flora Silvestres (CITES) que se consideran amenazadas o pueden verse amenazadas por el comercio. La realización de ejercicios de diligencia debida requiere acceso a información con la cual fundamentar tales decisiones; sin embargo, no está claro hasta qué punto se dispone de información. Usamos como estudio de caso el comercio de plantas de jarra tropicales (Nepenthes) con fines hortícolas para determinar cuánta información hay disponible. Realizamos un estudio sistemático del comercio en línea de las especies descritas entre 1996 y 2016. Para las especies encontradas en el comercio, hicimos referencias cruzadas con la base de datos de comercio CITES y consultamos a las Autoridades Administrativas CITES pertinentes y a los Puntos Focales Nacionales de Acceso y Distribución de Beneficios. De las 83 especies con descripción reciente, el 61% se pusieron a la venta en línea en 2018. A pesar de que todas las especies de Nepenthes están catalogadas en CITES, sólo el 23% (n = 19) de las especies que se vendían en línea figuraban en la base de datos sobre comercio CITES, y sólo tres procedían de los países de origen. Treinta y dos de estas especies no tenían comercio internacional registrado según la base de datos. Las autoridades de gestión de CITES de los países de origen confirmaron que se permitió el comercio de 5 de las 32 especies. La falta de registros CITES puede explicarse por el comercio de «Nepenthes spp¼ o como partes y derivados exentos. Sin embargo, es probable que se exijan permisos de recolección y comercialización en el marco del Protocolo de Nagoya sobre Acceso y Participación en los Beneficios (APB) del Convenio sobre la Diversidad Biológica. Contactamos a los Puntos Focales Nacionales de APB para determinar si se habían expedido permisos de recolección o comercialización para las especies restantes. Sólo dos de los siete puntos focales respondieron y ambos afirmaron que no se había expedido ningún permiso. La falta de información de rastreo o de respuesta en relación con la expedición de permisos de recolección y comercialización es preocupante y obstaculiza la diligencia debida de las empresas y los consumidores que desean asegurarse de que su comercio es legal, sostenible y ético.


Assuntos
Comércio , Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Conservação dos Recursos Naturais/métodos , Conservação dos Recursos Naturais/legislação & jurisprudência , Horticultura , Magnoliopsida/fisiologia
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