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1.
Cell ; 185(4): 641-653.e17, 2022 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-35123651

RESUMO

HIV-1 Env mediates viral entry into host cells and is the sole target for neutralizing antibodies. However, Env structure and organization in its native virion context has eluded detailed characterization. Here, we used cryo-electron tomography to analyze Env in mature and immature HIV-1 particles. Immature particles showed distinct Env positioning relative to the underlying Gag lattice, providing insights into long-standing questions about Env incorporation. A 9.1-Å sub-tomogram-averaged reconstruction of virion-bound Env in conjunction with structural mass spectrometry revealed unexpected features, including a variable central core of the gp41 subunit, heterogeneous glycosylation between protomers, and a flexible stalk that allows Env tilting and variable exposure of neutralizing epitopes. Together, our results provide an integrative understanding of HIV assembly and structural variation in Env antigen presentation.


Assuntos
Microscopia Crioeletrônica , Tomografia com Microscopia Eletrônica , Vírion/ultraestrutura , Produtos do Gene env do Vírus da Imunodeficiência Humana/ultraestrutura , Produtos do Gene gag do Vírus da Imunodeficiência Humana/ultraestrutura , 2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/farmacologia , Sequência de Aminoácidos , Dissulfetos/farmacologia , Epitopos/química , Células HEK293 , Proteína gp41 do Envelope de HIV/química , Humanos , Espectrometria de Massa com Troca Hidrogênio-Deutério , Modelos Moleculares , Testes de Neutralização , Peptídeos/química , Polissacarídeos/química , Domínios Proteicos , Estrutura Secundária de Proteína , Subunidades Proteicas/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/química
2.
Cell ; 183(5): 1367-1382.e17, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33160446

RESUMO

A safe, effective, and scalable vaccine is needed to halt the ongoing SARS-CoV-2 pandemic. We describe the structure-based design of self-assembling protein nanoparticle immunogens that elicit potent and protective antibody responses against SARS-CoV-2 in mice. The nanoparticle vaccines display 60 SARS-CoV-2 spike receptor-binding domains (RBDs) in a highly immunogenic array and induce neutralizing antibody titers 10-fold higher than the prefusion-stabilized spike despite a 5-fold lower dose. Antibodies elicited by the RBD nanoparticles target multiple distinct epitopes, suggesting they may not be easily susceptible to escape mutations, and exhibit a lower binding:neutralizing ratio than convalescent human sera, which may minimize the risk of vaccine-associated enhanced respiratory disease. The high yield and stability of the assembled nanoparticles suggest that manufacture of the nanoparticle vaccines will be highly scalable. These results highlight the utility of robust antigen display platforms and have launched cGMP manufacturing efforts to advance the SARS-CoV-2-RBD nanoparticle vaccine into the clinic.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , Nanopartículas/química , Domínios Proteicos/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/química , Vacinação , Adolescente , Adulto , Idoso , Animais , COVID-19/virologia , Chlorocebus aethiops , Estudos de Coortes , Epitopos/imunologia , Feminino , Células HEK293 , Humanos , Macaca nemestrina , Masculino , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Células Vero , Adulto Jovem
3.
Nature ; 619(7970): 585-594, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37468583

RESUMO

Understanding kidney disease relies on defining the complexity of cell types and states, their associated molecular profiles and interactions within tissue neighbourhoods1. Here we applied multiple single-cell and single-nucleus assays (>400,000 nuclei or cells) and spatial imaging technologies to a broad spectrum of healthy reference kidneys (45 donors) and diseased kidneys (48 patients). This has provided a high-resolution cellular atlas of 51 main cell types, which include rare and previously undescribed cell populations. The multi-omic approach provides detailed transcriptomic profiles, regulatory factors and spatial localizations spanning the entire kidney. We also define 28 cellular states across nephron segments and interstitium that were altered in kidney injury, encompassing cycling, adaptive (successful or maladaptive repair), transitioning and degenerative states. Molecular signatures permitted the localization of these states within injury neighbourhoods using spatial transcriptomics, while large-scale 3D imaging analysis (around 1.2 million neighbourhoods) provided corresponding linkages to active immune responses. These analyses defined biological pathways that are relevant to injury time-course and niches, including signatures underlying epithelial repair that predicted maladaptive states associated with a decline in kidney function. This integrated multimodal spatial cell atlas of healthy and diseased human kidneys represents a comprehensive benchmark of cellular states, neighbourhoods, outcome-associated signatures and publicly available interactive visualizations.


Assuntos
Perfilação da Expressão Gênica , Nefropatias , Rim , Análise de Célula Única , Transcriptoma , Humanos , Núcleo Celular/genética , Rim/citologia , Rim/lesões , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/patologia , Transcriptoma/genética , Estudos de Casos e Controles , Imageamento Tridimensional
4.
N Engl J Med ; 388(14): 1259-1271, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36762865

RESUMO

BACKGROUND: Trials of the efficacy and safety of endovascular thrombectomy in patients with large ischemic strokes have been carried out in limited populations. METHODS: We performed a prospective, randomized, open-label, adaptive, international trial involving patients with stroke due to occlusion of the internal carotid artery or the first segment of the middle cerebral artery to assess endovascular thrombectomy within 24 hours after onset. Patients had a large ischemic-core volume, defined as an Alberta Stroke Program Early Computed Tomography Score of 3 to 5 (range, 0 to 10, with lower scores indicating larger infarction) or a core volume of at least 50 ml on computed tomography perfusion or diffusion-weighted magnetic resonance imaging. Patients were assigned in a 1:1 ratio to endovascular thrombectomy plus medical care or to medical care alone. The primary outcome was the modified Rankin scale score at 90 days (range, 0 to 6, with higher scores indicating greater disability). Functional independence was a secondary outcome. RESULTS: The trial was stopped early for efficacy; 178 patients had been assigned to the thrombectomy group and 174 to the medical-care group. The generalized odds ratio for a shift in the distribution of modified Rankin scale scores toward better outcomes in favor of thrombectomy was 1.51 (95% confidence interval [CI], 1.20 to 1.89; P<0.001). A total of 20% of the patients in the thrombectomy group and 7% in the medical-care group had functional independence (relative risk, 2.97; 95% CI, 1.60 to 5.51). Mortality was similar in the two groups. In the thrombectomy group, arterial access-site complications occurred in 5 patients, dissection in 10, cerebral-vessel perforation in 7, and transient vasospasm in 11. Symptomatic intracranial hemorrhage occurred in 1 patient in the thrombectomy group and in 2 in the medical-care group. CONCLUSIONS: Among patients with large ischemic strokes, endovascular thrombectomy resulted in better functional outcomes than medical care but was associated with vascular complications. Cerebral hemorrhages were infrequent in both groups. (Funded by Stryker Neurovascular; SELECT2 ClinicalTrials.gov number, NCT03876457.).


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Trombectomia , Humanos , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/cirurgia , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/métodos , Fibrinolíticos/efeitos adversos , Fibrinolíticos/uso terapêutico , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/cirurgia , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/cirurgia , Trombectomia/efeitos adversos , Trombectomia/métodos , Resultado do Tratamento , Infarto da Artéria Cerebral Média/complicações , Doenças das Artérias Carótidas/complicações , Recuperação de Função Fisiológica , Hemorragia Cerebral/induzido quimicamente , Hemorragia Cerebral/etiologia
5.
PLoS Pathog ; 20(1): e1011866, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38236788

RESUMO

Rosellinia necatrix is a prevalent soil-borne plant-pathogenic fungus that is the causal agent of white root rot disease in a broad range of host plants. The limited availability of genomic resources for R. necatrix has complicated a thorough understanding of its infection biology. Here, we sequenced nine R. necatrix strains with Oxford Nanopore sequencing technology, and with DNA proximity ligation we generated a gapless assembly of one of the genomes into ten chromosomes. Whereas many filamentous pathogens display a so-called two-speed genome with more dynamic and more conserved compartments, the R. necatrix genome does not display such genome compartmentalization. It has recently been proposed that fungal plant pathogens may employ effectors with antimicrobial activity to manipulate the host microbiota to promote infection. In the predicted secretome of R. necatrix, 26 putative antimicrobial effector proteins were identified, nine of which are expressed during plant colonization. Two of the candidates were tested, both of which were found to possess selective antimicrobial activity. Intriguingly, some of the inhibited bacteria are antagonists of R. necatrix growth in vitro and can alleviate R. necatrix infection on cotton plants. Collectively, our data show that R. necatrix encodes antimicrobials that are expressed during host colonization and that may contribute to modulation of host-associated microbiota to stimulate disease development.


Assuntos
Anti-Infecciosos , Ascomicetos , Ascomicetos/genética , Plantas , Anti-Infecciosos/metabolismo
6.
Cell ; 145(4): 513-28, 2011 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-21565611

RESUMO

Nephronophthisis (NPHP), Joubert (JBTS), and Meckel-Gruber (MKS) syndromes are autosomal-recessive ciliopathies presenting with cystic kidneys, retinal degeneration, and cerebellar/neural tube malformation. Whether defects in kidney, retinal, or neural disease primarily involve ciliary, Hedgehog, or cell polarity pathways remains unclear. Using high-confidence proteomics, we identified 850 interactors copurifying with nine NPHP/JBTS/MKS proteins and discovered three connected modules: "NPHP1-4-8" functioning at the apical surface, "NPHP5-6" at centrosomes, and "MKS" linked to Hedgehog signaling. Assays for ciliogenesis and epithelial morphogenesis in 3D renal cultures link renal cystic disease to apical organization defects, whereas ciliary and Hedgehog pathway defects lead to retinal or neural deficits. Using 38 interactors as candidates, linkage and sequencing analysis of 250 patients identified ATXN10 and TCTN2 as new NPHP-JBTS genes, and our Tctn2 mouse knockout shows neural tube and Hedgehog signaling defects. Our study further illustrates the power of linking proteomic networks and human genetics to uncover critical disease pathways.


Assuntos
Doenças Renais Císticas/genética , Proteínas de Membrana/genética , Transdução de Sinais , Animais , Ataxina-10 , Centrossomo/metabolismo , Cílios/metabolismo , Transtornos da Motilidade Ciliar/genética , Encefalocele/genética , Proteínas Hedgehog/metabolismo , Humanos , Doenças Renais Císticas/metabolismo , Camundongos , Células NIH 3T3 , Proteínas do Tecido Nervoso/genética , Doenças Renais Policísticas/genética , Retinose Pigmentar , Peixe-Zebra
7.
Proc Natl Acad Sci U S A ; 120(46): e2308911120, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37948585

RESUMO

Coordinated pair bonds are common in birds and also occur in many other taxa. How do animals solve the social dilemmas they face in coordinating with a partner? We developed an evolutionary model to explore this question, based on observations that a) neuroendocrine feedback provides emotional bookkeeping which is thought to play a key role in vertebrate social bonds and b) these bonds are developed and maintained via courtship interactions that include low-stakes social dilemmas. Using agent-based simulation, we found that emotional bookkeeping and courtship sustained cooperation in the iterated prisoner's dilemma in noisy environments, especially when combined. However, when deceitful defection was possible at low cost, courtship often increased cooperation, whereas emotional bookkeeping decreased it.


Assuntos
Comportamento Cooperativo , Corte , Animais , Emoções , Dilema do Prisioneiro , Simulação por Computador , Teoria dos Jogos
8.
Lancet ; 403(10428): 731-740, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38346442

RESUMO

BACKGROUND: Multiple randomised trials have shown efficacy and safety of endovascular thrombectomy in patients with large ischaemic stroke. The aim of this study was to evaluate long-term (ie, at 1 year) evidence of benefit of thrombectomy for these patients. METHODS: SELECT2 was a phase 3, open-label, international, randomised controlled trial with blinded endpoint assessment, conducted at 31 hospitals in the USA, Canada, Spain, Switzerland, Australia, and New Zealand. Patients aged 18-85 years with ischaemic stroke due to proximal occlusion of the internal carotid artery or of the first segment of the middle cerebral artery, showing large ischaemic core on non-contrast CT (Alberta Stroke Program Early Computed Tomographic Score of 3-5 [range 0-10, with lower values indicating larger infarctions]) or measuring 50 mL or more on CT perfusion and MRI, were randomly assigned, within 24 h of ischaemic stroke onset, to thrombectomy plus medical care or to medical care alone. The primary outcome for this analysis was the ordinal modified Rankin Scale (range 0-6, with higher scores indicating greater disability) at 1-year follow-up in an intention-to-treat population. The trial is registered at ClinicalTrials.gov (NCT03876457) and is completed. FINDINGS: The trial was terminated early for efficacy at the 90-day follow-up after 352 patients had been randomly assigned (178 to thrombectomy and 174 to medical care only) between Oct 11, 2019, and Sept 9, 2022. Thrombectomy significantly improved the 1-year modified Rankin Scale score distribution versus medical care alone (Wilcoxon-Mann-Whitney probability of superiority 0·59 [95% CI 0·53-0·64]; p=0·0019; generalised odds ratio 1·43 [95% CI 1·14-1·78]). At the 1-year follow-up, 77 (45%) of 170 patients receiving thrombectomy had died, compared with 83 (52%) of 159 patients receiving medical care only (1-year mortality relative risk 0·89 [95% CI 0·71-1·11]). INTERPRETATION: In patients with ischaemic stroke due to a proximal occlusion and large core, thrombectomy plus medical care provided a significant functional outcome benefit compared with medical care alone at 1-year follow-up. FUNDING: Stryker Neurovascular.


Assuntos
Isquemia Encefálica , Procedimentos Endovasculares , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Isquemia Encefálica/terapia , Isquemia Encefálica/tratamento farmacológico , Resultado do Tratamento , Procedimentos Endovasculares/métodos , Trombectomia/métodos , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/cirurgia , Alberta , Fibrinolíticos/uso terapêutico
9.
Brief Bioinform ; 24(3)2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37150778

RESUMO

With the aim of analyzing large-sized multidimensional single-cell datasets, we are describing a method for Cosine-based Tanimoto similarity-refined graph for community detection using Leiden's algorithm (CosTaL). As a graph-based clustering method, CosTaL transforms the cells with high-dimensional features into a weighted k-nearest-neighbor (kNN) graph. The cells are represented by the vertices of the graph, while an edge between two vertices in the graph represents the close relatedness between the two cells. Specifically, CosTaL builds an exact kNN graph using cosine similarity and uses the Tanimoto coefficient as the refining strategy to re-weight the edges in order to improve the effectiveness of clustering. We demonstrate that CosTaL generally achieves equivalent or higher effectiveness scores on seven benchmark cytometry datasets and six single-cell RNA-sequencing datasets using six different evaluation metrics, compared with other state-of-the-art graph-based clustering methods, including PhenoGraph, Scanpy and PARC. As indicated by the combined evaluation metrics, Costal has high efficiency with small datasets and acceptable scalability for large datasets, which is beneficial for large-scale analysis.


Assuntos
Algoritmos , Análise de Dados , Análise por Conglomerados
10.
Proc Natl Acad Sci U S A ; 119(6)2022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35131847

RESUMO

Predictions of relative stabilities of (competing) molecular crystals are of great technological relevance, most notably for the pharmaceutical industry. However, they present a long-standing challenge for modeling, as often minuscule free energy differences are sensitively affected by the description of electronic structure, the statistical mechanics of the nuclei and the cell, and thermal expansion. The importance of these effects has been individually established, but rigorous free energy calculations for general molecular compounds, which simultaneously account for all effects, have hitherto not been computationally viable. Here we present an efficient "end to end" framework that seamlessly combines state-of-the art electronic structure calculations, machine-learning potentials, and advanced free energy methods to calculate ab initio Gibbs free energies for general organic molecular materials. The facile generation of machine-learning potentials for a diverse set of polymorphic compounds-benzene, glycine, and succinic acid-and predictions of thermodynamic stabilities in qualitative and quantitative agreement with experiments highlight that predictive thermodynamic studies of industrially relevant molecular materials are no longer a daunting task.

11.
Stroke ; 55(5): 1438-1448, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648281

RESUMO

ARISE (Aneurysm/AVM/cSDH Roundtable Discussion With Industry and Stroke Experts) organized a one-and-a-half day meeting and workshop and brought together representatives from academia, industry, and government to discuss the most promising approaches to improve outcomes for patients with chronic subdural hematoma (cSDH). The emerging role of middle meningeal artery embolization in clinical practice and the design of current and potential future trials were the primary focuses of discussion. Existing evidence for imaging, indications, agents, and techniques was reviewed, and areas of priority for study and key questions surrounding the development of new and existing treatments for cSDH were identified. Multiple randomized, controlled trials have met their primary efficacy end points, providing high-level evidence that middle meningeal artery embolization is a potent adjunctive therapy to the standard (surgical and nonsurgical) management of neurologically stable cSDH patients in terms of reducing rates of disease recurrence. Pooled data analyses following the formal conclusion and publication of these trials will form a robust foundation upon which guidelines can be strengthened for cSDH treatment modalities and optimal patient selection, as well as delineate future lines of investigation.


Assuntos
Hematoma Subdural Crônico , Humanos , Consenso , Embolização Terapêutica/métodos , Hematoma Subdural Crônico/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto
12.
Stroke ; 55(5): 1449-1463, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38648282

RESUMO

Brain arteriovenous malformations (bAVMs) are complex, and rare arteriovenous shunts that present with a wide range of signs and symptoms, with intracerebral hemorrhage being the most severe. Despite prior societal position statements, there is no consensus on the management of these lesions. ARISE (Aneurysm/bAVM/cSDH Roundtable Discussion With Industry and Stroke Experts) was convened to discuss evidence-based approaches and enhance our understanding of these complex lesions. ARISE identified the need to develop scales to predict the risk of rupture of bAVMs, and the use of common data elements to perform prospective registries and clinical studies. Additionally, the group underscored the need for comprehensive patient management with specialized centers with expertise in cranial and spinal microsurgery, neurological endovascular surgery, and stereotactic radiosurgery. The collection of prospective multicenter data and gross specimens was deemed essential for improving bAVM characterization, genetic evaluation, and phenotyping. Finally, bAVMs should be managed within a multidisciplinary framework, with clinical studies and research conducted collaboratively across multiple centers, harnessing the collective expertise and centralization of resources.


Assuntos
Malformações Arteriovenosas Intracranianas , Humanos , Hemorragia Cerebral/terapia , Procedimentos Endovasculares/métodos , Malformações Arteriovenosas Intracranianas/terapia , Radiocirurgia/métodos
13.
J Am Chem Soc ; 146(17): 11622-11633, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38639470

RESUMO

The design of efficient electrocatalysts is limited by scaling relationships governing trade-offs between thermodynamic and kinetic performance metrics. This ″iron law″ of electrocatalysis arises from synthetic design strategies, where structural alterations to a catalyst must balance nucleophilic versus electrophilic character. Efforts to circumvent this fundamental impasse have focused on bioinspired applications of extended coordination spheres and charged sites proximal to a catalytic center. Herein, we report evidence for breaking a molecular scaling relationship involving electrocatalysis of the oxygen reduction reaction (ORR) by leveraging ligand design. We achieve this using a binuclear catalyst (a diiron porphyrin), featuring a macrocyclic ligand with extended electronic conjugation. This ligand motif delocalizes electrons across the molecular scaffold, improving the catalyst's nucleophilic and electrophilic character. As a result, our binuclear catalyst exhibits low overpotential and high catalytic turnover frequency, breaking the traditional trade-off between these two metrics.

14.
Kidney Int ; 105(2): 312-327, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37977366

RESUMO

Acute kidney injury (AKI) is a common condition that lacks effective treatments. In part, this shortcoming is due to an incomplete understanding of the genetic mechanisms that control pathogenesis and recovery. Identifying the molecular and genetic regulators unique to nephron segments that dictate vulnerability to injury and regenerative potential could lead to new therapeutic targets to treat ischemic kidney injury. Pax2 and Pax8 are homologous transcription factors with overlapping functions that are critical for kidney development and are re-activated in AKI. Here, we examined the role of Pax2 and Pax8 in recovery from ischemic AKI and found them upregulated after severe AKI and correlated with chronic injury. Surprisingly, proximal-tubule-selective deletion of Pax2 and Pax8 resulted in a less severe chronic injury phenotype. This effect was mediated by protection against the acute insult, similar to pre-conditioning. Prior to injury, Pax2 and Pax8 mutant mice develop a unique subpopulation of proximal tubule cells in the S3 segment that displayed features usually seen only in acute or chronic injury. The expression signature of these cells was strongly enriched with genes associated with other mechanisms of protection against ischemic AKI including caloric restriction, hypoxic pre-conditioning, and female sex. Thus, our results identified a novel role for Pax2 and Pax8 in mature proximal tubules that regulates critical genes and pathways involved in both the injury response and protection from ischemic AKI.


Assuntos
Injúria Renal Aguda , Túbulos Renais Proximais , Fator de Transcrição PAX2 , Fator de Transcrição PAX8 , Insuficiência Renal Crônica , Animais , Feminino , Camundongos , Injúria Renal Aguda/complicações , Injúria Renal Aguda/genética , Isquemia/complicações , Túbulos Renais Proximais/patologia , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/genética , Traumatismo por Reperfusão/genética , Fator de Transcrição PAX8/genética , Fator de Transcrição PAX8/metabolismo , Fator de Transcrição PAX2/genética , Fator de Transcrição PAX2/metabolismo
15.
Cytometry A ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38995093

RESUMO

Senescence is an irreversible arrest of the cell cycle that can be characterized by markers of senescence such as p16, p21, and KI-67. The characterization of different senescence-associated phenotypes requires selection of the most relevant senescence markers to define reliable cytometric methodologies. Mass cytometry (a.k.a. Cytometry by time of flight, CyTOF) can monitor up to 40 different cell markers at the single-cell level and has the potential to integrate multiple senescence and other phenotypic markers to identify senescent cells within a complex tissue such as skeletal muscle, with greater accuracy and scalability than traditional bulk measurements and flow cytometry-based measurements. This article introduces an analysis framework for detecting putative senescent cells based on clustering, outlier detection, and Boolean logic for outliers. Results show that the pipeline can identify putative senescent cells in skeletal muscle with well-established markers such as p21 and potential markers such as GAPDH. It was also found that heterogeneity of putative senescent cells in skeletal muscle can partly be explained by their cell type. Additionally, autophagy-related proteins ATG4A, LRRK2, and GLB1 were identified as important proteins in predicting the putative senescent population, providing insights into the association between autophagy and senescence. It was observed that sex did not affect the proportion of putative senescent cells among total cells. However, age did have an effect, with a higher proportion observed in fibro/adipogenic progenitors (FAPs), satellite cells, M1 and M2 macrophages from old mice. Moreover, putative senescent cells from muscle of old and young mice show different expression levels of senescence-related proteins, with putative senescent cells of old mice having higher levels of p21 and GAPDH, whereas putative senescent cells of young mice had higher levels of IL-6. Overall, the analysis framework prioritizes multiple senescence-associated proteins to characterize putative senescent cells sourced from tissue made of different cell types.

16.
Reproduction ; 167(1)2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37874784

RESUMO

In brief: The localization and abundance of the sperm BSP proteins correlate with in vitro fertility in domestic bulls used in artificial insemination service. Abstract: Binder of sperm (BSP) proteins, secreted mainly by the accessory sex glands, are the major protein family present in bovine seminal plasma and on the sperm surface after ejaculation. In vivo, BSP proteins facilitate sperm capacitation and sperm reservoir formation; however, their impact on sperm function within the in vitro systems is less clear. Therefore, this biomarker-based study aimed to characterize the localization and abundance of BSP proteins from in vitro processed frozen-thawed bovine spermatozoa. Using image-based flow cytometry and Western blotting, BSP protein localization, abundance, membrane and acrosomal integrity were investigated in the supernatant (nonmotile) and pellet (motile) fractions of gradient-separated bull spermatozoa. Spermatozoa from the supernatant fraction had high enrichment of all BSP proteins investigated (BSP1, BSP3, BSP5; P < 0.05) when compared to the pellet fraction. In the pellet fraction, BSP1 and BSP3 bound predominately to the acrosomal region, whereas BSP5 had a high affinity for the midpiece. However, in the supernatant fraction, BSP proteins predominately coated the entire sperm surface resulting in the loss of regional specificity. High BSP protein abundance in the spermatozoa also correlated with acrosome and membrane damage. Whereas a high abundance of BSP5 correlated with low embryo cleavage rates, high abundance of BSP1 on the sperm head coincided with a high blastocyst rate. Therefore, changes in the quantity and localization of specific BSP proteins could act as potential biomarkers of sperm quality and fertility.


Assuntos
Sêmen , Proteínas do Espermatozoide , Animais , Bovinos , Masculino , Espermatozoides/metabolismo , Congelamento , Proteínas/metabolismo
17.
Am J Obstet Gynecol ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38494071

RESUMO

BACKGROUND: There are limited data to guide the diagnosis and management of vasa previa. Currently, what is known is largely based on case reports or series and cohort studies. OBJECTIVE: This study aimed to systematically collect and classify expert opinions and achieve consensus on the diagnosis and clinical management of vasa previa using focus group discussions and a Delphi technique. STUDY DESIGN: A 4-round focus group discussion and a 3-round Delphi survey of an international panel of experts on vasa previa were conducted. Experts were selected on the basis of their publication record on vasa previa. First, we convened a focus group discussion panel of 20 experts and agreed on which issues were unresolved in the diagnosis and management of vasa previa. A 3-round anonymous electronic survey was then sent to the full expert panel. Survey questions were presented on the diagnosis and management of vasa previa, which the experts were asked to rate on a 5-point Likert scale (from "strongly disagree"=1 to "strongly agree"=5). Consensus was defined as a median score of 5. Following responses to each round, any statements that had median scores of ≤3 were deemed to have had no consensus and were excluded. Statements with a median score of 4 were revised and re-presented to the experts in the next round. Consensus and nonconsensus statements were then aggregated. RESULTS: A total of 68 international experts were invited to participate in the study, of which 57 participated. Experts were from 13 countries on 5 continents and have contributed to >80% of published cohort studies on vasa previa, as well as national and international society guidelines. Completion rates were 84%, 93%, and 91% for the first, second, and third rounds, respectively, and 71% completed all 3 rounds. The panel reached a consensus on 26 statements regarding the diagnosis and key points of management of vasa previa, including the following: (1) although there is no agreement on the distance between the fetal vessels and the cervical internal os to define vasa previa, the definition should not be limited to a 2-cm distance; (2) all pregnancies should be screened for vasa previa with routine examination for placental cord insertion and a color Doppler sweep of the region over the cervix at the second-trimester anatomy scan; (3) when a low-lying placenta or placenta previa is found in the second trimester, a transvaginal ultrasound with Doppler should be performed at approximately 32 weeks to rule out vasa previa; (4) outpatient management of asymptomatic patients without risk factors for preterm birth is reasonable; (5) asymptomatic patients with vasa previa should be delivered by scheduled cesarean delivery between 35 and 37 weeks of gestation; and (6) there was no agreement on routine hospitalization, avoidance of intercourse, or use of 3-dimensional ultrasound for diagnosis of vasa previa. CONCLUSION: Through focus group discussion and a Delphi process, an international expert panel reached consensus on the definition, screening, clinical management, and timing of delivery in vasa previa, which could inform the development of new clinical guidelines.

18.
Circ Res ; 130(10): 1550-1564, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35430873

RESUMO

BACKGROUND: Renal T cells contribute importantly to hypertension, but the underlying mechanism is incompletely understood. We reported that CD8Ts directly stimulate distal convoluted tubule cells (DCTs) to increase NCC (sodium chloride co-transporter) expression and salt reabsorption. However, the mechanistic basis of this pathogenic pathway that promotes hypertension remains to be elucidated. METHODS: We used mouse models of DOCA+salt (DOCA) treatment and adoptive transfer of CD8+ T cells (CD8T) from hypertensive animals to normotensive animals in in vivo studies. Co-culture of mouse DCTs and CD8Ts was used as in vitro model to test the effect of CD8T activation in promoting NCC-mediated sodium retention and to identify critical molecular players contributing to the CD8T-DCT interaction. Interferon (IFNγ)-KO mice and mice receiving renal tubule-specific knockdown of PDL1 were used to verify in vitro findings. Blood pressure was continuously monitored via radio-biotelemetry, and kidney samples were saved at experimental end points for analysis. RESULTS: We identified critical molecular players and demonstrated their roles in augmenting the CD8T-DCT interaction leading to salt-sensitive hypertension. We found that activated CD8Ts exhibit enhanced interaction with DCTs via IFN-γ-induced upregulation of MHC-I and PDL1 in DCTs, thereby stimulating higher expression of NCC in DCTs to cause excessive salt retention and progressive elevation of blood pressure. Eliminating IFN-γ or renal tubule-specific knockdown of PDL1 prevented T cell homing into the kidney, thereby attenuating hypertension in 2 different mouse models. CONCLUSIONS: Our results identified the role of activated CD8Ts in contributing to increased sodium retention in DCTS through the IFNγ-PDL1 pathway. These findings provide a new mechanism for T cell involvement in the pathogenesis of hypertension and reveal novel therapeutic targets.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão , Animais , Linfócitos T CD8-Positivos/metabolismo , Acetato de Desoxicorticosterona/metabolismo , Acetato de Desoxicorticosterona/farmacologia , Modelos Animais de Doenças , Hipertensão/metabolismo , Túbulos Renais Distais/metabolismo , Túbulos Renais Distais/patologia , Camundongos , Sódio/metabolismo , Simportadores de Cloreto de Sódio/metabolismo , Cloreto de Sódio na Dieta
19.
Fish Shellfish Immunol ; 148: 109472, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38438059

RESUMO

The shrimp industry has historically been affected by viral and bacterial diseases. One of the most recent emerging diseases is Acute Hepatopancreatic Necrosis Disease (AHPND), which causes severe mortality. Despite its significance to sanitation and economics, little is known about the molecular response of shrimp to this disease. Here, we present the cellular and transcriptomic responses of Litopenaeus vannamei exposed to two Vibrio parahaemolyticus strains for 98 h, wherein one is non-pathogenic (VpN) and the other causes AHPND (VpP). Exposure to the VpN strain resulted in minor alterations in hepatopancreas morphology, including reductions in the size of R and B cells and detachments of small epithelial cells from 72 h onwards. On the other hand, exposure to the VpP strain is characterized by acute detachment of epithelial cells from the hepatopancreatic tubules and infiltration of hemocytes in the inter-tubular spaces. At the end of exposure, RNA-Seq analysis revealed functional enrichment in biological processes, such as the toll3 receptor signaling pathway, apoptotic processes, and production of molecular mediators involved in the inflammatory response of shrimp exposed to VpN treatment. The biological processes identified in the VpP treatment include superoxide anion metabolism, innate immune response, antimicrobial humoral response, and toll3 receptor signaling pathway. Furthermore, KEGG enrichment analysis revealed metabolic pathways associated with survival, cell adhesion, and reactive oxygen species, among others, for shrimp exposed to VpP. Our study proves the differential immune responses to two strains of V. parahaemolyticus, one pathogenic and the other nonpathogenic, enlarges our knowledge on the evolution of AHPND in L. vannamei, and uncovers unique perspectives on establishing genomic resources that may function as a groundwork for detecting probable molecular markers linked to the immune system in shrimp.


Assuntos
Penaeidae , Vibrio parahaemolyticus , Animais , Vibrio parahaemolyticus/fisiologia , Perfilação da Expressão Gênica/veterinária , Transcriptoma , Hepatopâncreas/patologia , Necrose/microbiologia , Doença Aguda
20.
J Comput Aided Mol Des ; 38(1): 9, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38351144

RESUMO

Notwithstanding the wide adoption of the OECD principles (or best practices) for QSAR modeling, disparities between in silico predictions and experimental results are frequent, suggesting that model predictions are often too optimistic. Of these OECD principles, the applicability domain (AD) estimation has been recognized in several reports in the literature to be one of the most challenging, implying that the actual reliability measures of model predictions are often unreliable. Applying tree-based error analysis workflows on 5 QSAR models reported in the literature and available in the QsarDB repository, i.e., androgen receptor bioactivity (agonists, antagonists, and binders, respectively) and membrane permeability (highest membrane permeability and the intrinsic permeability), we demonstrate that predictions erroneously tagged as reliable (AD prediction errors) overwhelmingly correspond to instances in subspaces (cohorts) with the highest prediction error rates, highlighting the inhomogeneity of the AD space. In this sense, we call for more stringent AD analysis guidelines which require the incorporation of model error analysis schemes, to provide critical insight on the reliability of underlying AD algorithms. Additionally, any selected AD method should be rigorously validated to demonstrate its suitability for the model space over which it is applied. These steps will ultimately contribute to more accurate estimations of the reliability of model predictions. Finally, error analysis may also be useful in "rational" model refinement in that data expansion efforts and model retraining are focused on cohorts with the highest error rates.


Assuntos
Algoritmos , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes
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