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1.
Cell ; 186(21): 4514-4527.e14, 2023 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-37757828

RESUMO

Autozygosity is associated with rare Mendelian disorders and clinically relevant quantitative traits. We investigated associations between the fraction of the genome in runs of homozygosity (FROH) and common diseases in Genes & Health (n = 23,978 British South Asians), UK Biobank (n = 397,184), and 23andMe. We show that restricting analysis to offspring of first cousins is an effective way of reducing confounding due to social/environmental correlates of FROH. Within this group in G&H+UK Biobank, we found experiment-wide significant associations between FROH and twelve common diseases. We replicated associations with type 2 diabetes (T2D) and post-traumatic stress disorder via within-sibling analysis in 23andMe (median n = 480,282). We estimated that autozygosity due to consanguinity accounts for 5%-18% of T2D cases among British Pakistanis. Our work highlights the possibility of widespread non-additive genetic effects on common diseases and has important implications for global populations with high rates of consanguinity.


Assuntos
Consanguinidade , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/genética , Homozigoto , Fenótipo , Polimorfismo de Nucleotídeo Único , Bancos de Espécimes Biológicos , Genoma Humano , Predisposição Genética para Doença , Reino Unido
2.
Cell ; 182(5): 1198-1213.e14, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32888493

RESUMO

Most loci identified by GWASs have been found in populations of European ancestry (EUR). In trans-ethnic meta-analyses for 15 hematological traits in 746,667 participants, including 184,535 non-EUR individuals, we identified 5,552 trait-variant associations at p < 5 × 10-9, including 71 novel associations not found in EUR populations. We also identified 28 additional novel variants in ancestry-specific, non-EUR meta-analyses, including an IL7 missense variant in South Asians associated with lymphocyte count in vivo and IL-7 secretion levels in vitro. Fine-mapping prioritized variants annotated as functional and generated 95% credible sets that were 30% smaller when using the trans-ethnic as opposed to the EUR-only results. We explored the clinical significance and predictive value of trans-ethnic variants in multiple populations and compared genetic architecture and the effect of natural selection on these blood phenotypes between populations. Altogether, our results for hematological traits highlight the value of a more global representation of populations in genetic studies.


Assuntos
Povo Asiático/genética , Mutação de Sentido Incorreto/genética , Polimorfismo de Nucleotídeo Único/genética , População Branca/genética , Genética , Estudo de Associação Genômica Ampla/métodos , Células HEK293 , Humanos , Interleucina-7/genética , Fenótipo
3.
Nature ; 633(8030): 608-614, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39261734

RESUMO

Human genetic studies of common variants have provided substantial insight into the biological mechanisms that govern ovarian ageing1. Here we report analyses of rare protein-coding variants in 106,973 women from the UK Biobank study, implicating genes with effects around five times larger than previously found for common variants (ETAA1, ZNF518A, PNPLA8, PALB2 and SAMHD1). The SAMHD1 association reinforces the link between ovarian ageing and cancer susceptibility1, with damaging germline variants being associated with extended reproductive lifespan and increased all-cause cancer risk in both men and women. Protein-truncating variants in ZNF518A are associated with shorter reproductive lifespan-that is, earlier age at menopause (by 5.61 years) and later age at menarche (by 0.56 years). Finally, using 8,089 sequenced trios from the 100,000 Genomes Project (100kGP), we observe that common genetic variants associated with earlier ovarian ageing associate with an increased rate of maternally derived de novo mutations. Although we were unable to replicate the finding in independent samples from the deCODE study, it is consistent with the expected role of DNA damage response genes in maintaining the genetic integrity of germ cells. This study provides evidence of genetic links between age of menopause and cancer risk.


Assuntos
Envelhecimento , Predisposição Genética para Doença , Menarca , Menopausa , Taxa de Mutação , Neoplasias , Ovário , Humanos , Feminino , Envelhecimento/genética , Ovário/metabolismo , Ovário/patologia , Menopausa/genética , Predisposição Genética para Doença/genética , Neoplasias/genética , Masculino , Menarca/genética , Pessoa de Meia-Idade , Reino Unido/epidemiologia , Adulto , Idoso , Mutação em Linhagem Germinativa/genética
4.
Proc Natl Acad Sci U S A ; 120(27): e2301170120, 2023 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-37364094

RESUMO

Bacterial antimicrobial resistance (AMR) is among the most significant challenges to current human society. Exposing bacteria to antibiotics can activate their self-saving responses, e.g., filamentation, leading to the development of bacterial AMR. Understanding the molecular changes during the self-saving responses can reveal new inhibition methods of drug-resistant bacteria. Herein, we used an online microfluidics mass spectrometry system for real-time characterization of metabolic changes of bacteria during filamentation under the stimulus of antibiotics. Significant pathways, e.g., nucleotide metabolism and coenzyme A biosynthesis, correlated to the filamentation of extended-spectrum beta-lactamase-producing Escherichia coli (ESBL-E. coli) were identified. A cyclic dinucleotide, c-di-GMP, which is derived from nucleotide metabolism and reported closely related to bacterial resistance and tolerance, was observed significantly up-regulated during the bacterial filamentation. By using a chemical inhibitor, ebselen, to inhibit diguanylate cyclases which catalyzes the synthesis of c-di-GMP, the minimum inhibitory concentration of ceftriaxone against ESBL-E. coli was significantly decreased. This inhibitory effect was also verified with other ESBL-E. coli strains and other beta-lactam antibiotics, i.e., ampicillin. A mutant strain of ESBL-E. coli by knocking out the dgcM gene was used to demonstrate that the inhibition of the antibiotic resistance to beta-lactams by ebselen was mediated through the inhibition of the diguanylate cyclase DgcM and the modulation of c-di-GMP levels. Our study uncovers the molecular changes during bacterial filamentation and proposes a method to inhibit antibiotic-resistant bacteria by combining traditional antibiotics and chemical inhibitors against the enzymes involved in bacterial self-saving responses.


Assuntos
Infecções Bacterianas , Infecções por Escherichia coli , Humanos , Escherichia coli , beta-Lactamases/genética , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Bactérias/metabolismo , Nucleotídeos/farmacologia , Infecções por Escherichia coli/microbiologia
5.
Plant Physiol ; 195(1): 617-639, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38285060

RESUMO

Revealing the genetic basis for stress-resistant traits in extremophile plants will yield important information for crop improvement. Zygophyllum xanthoxylum, an extant species of the ancient Mediterranean, is a succulent xerophyte that can maintain a favorable water status under desert habitats; however, the genetic basis of this adaptive trait is poorly understood. Furthermore, the phylogenetic position of Zygophyllales, to which Z. xanthoxylum belongs, remains controversial. In this study, we sequenced and assembled the chromosome-level genome of Z. xanthoxylum. Phylogenetic analysis showed that Zygophyllales and Myrtales form a separated taxon as a sister to the clade comprising fabids and malvids, clarifying the phylogenetic position of Zygophyllales at whole-genome scale. Analysis of genomic and transcriptomic data revealed multiple critical mechanisms underlying the efficient osmotic adjustment using Na+ and K+ as "cheap" osmolytes that Z. xanthoxylum has evolved through the expansion and synchronized expression of genes encoding key transporters/channels and their regulators involved in Na+/K+ uptake, transport, and compartmentation. It is worth noting that ZxCNGC1;1 (cyclic nucleotide-gated channels) and ZxCNGC1;2 constituted a previously undiscovered energy-saving pathway for Na+ uptake. Meanwhile, the core genes involved in biosynthesis of cuticular wax also featured an expansion and upregulated expression, contributing to the water retention capacity of Z. xanthoxylum under desert environments. Overall, these findings boost the understanding of evolutionary relationships of eudicots, illustrate the unique water retention mechanism in the succulent xerophyte that is distinct from glycophyte, and thus provide valuable genetic resources for the improvement of stress tolerance in crops and insights into the remediation of sodic lands.


Assuntos
Filogenia , Água , Zygophyllum , Água/metabolismo , Zygophyllum/genética , Zygophyllum/metabolismo , Genoma de Planta , Regulação da Expressão Gênica de Plantas , Genômica/métodos
6.
Cell Mol Life Sci ; 81(1): 257, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874784

RESUMO

Adenine base editors (ABEs), consisting of CRISPR Cas nickase and deaminase, can chemically convert the A:T base pair to G:C. ABE8e, an evolved variant of the base editor ABE7.10, contains eight directed evolution mutations in its deaminase TadA8e that significantly increase its base editing activity. However, the functional implications of these mutations remain unclear. Here, we combined molecular dynamics (MD) simulations and experimental measurements to investigate the role of the directed-evolution mutations in the base editing catalysis. MD simulations showed that the DNA-binding affinity of TadA8e is higher than that of the original deaminase TadA7.10 in ABE7.10 and is mainly driven by electrostatic interactions. The directed-evolution mutations increase the positive charge density in the DNA-binding region, thereby enhancing the electrostatic attraction of TadA8e to DNA. We identified R111, N119 and N167 as the key mutations for the enhanced DNA binding and confirmed them by microscale thermophoresis (MST) and in vivo reversion mutation experiments. Unexpectedly, we also found that the directed mutations improved the thermal stability of TadA8e by ~ 12 °C (Tm, melting temperature) and that of ABE8e by ~ 9 °C, respectively. Our results demonstrate that the directed-evolution mutations improve the substrate-binding ability and protein stability of ABE8e, thus providing a rational basis for further editing optimisation of the system.


Assuntos
DNA , Evolução Molecular Direcionada , Edição de Genes , Simulação de Dinâmica Molecular , Mutação , DNA/metabolismo , DNA/genética , DNA/química , Edição de Genes/métodos , Adenina/metabolismo , Adenina/química , Estabilidade Proteica , Ligação Proteica , Eletricidade Estática , Sistemas CRISPR-Cas/genética
7.
Chem Soc Rev ; 53(18): 9306-9343, 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39143951

RESUMO

Cellulose, as the most abundant natural polymer on Earth, has long captured researchers' attention due to its high strength and modulus. Nevertheless, transferring its exceptional mechanical properties to macroscopic 2D and 3D materials poses numerous challenges. This review provides an overview of the research progress in the development of strong cellulose-based materials using both the "bottom-up" and "top-down" approaches. In the "bottom-up" strategy, various forms of regenerated cellulose-based materials and nanocellulose-based high-strength materials assembled by different methods are discussed. Under the "top-down" approach, the focus is on the development of reinforced cellulose-based materials derived from wood, bamboo, rattan and straw. Furthermore, a brief overview of the potential applications fordifferent types of strong cellulose-based materials is given, followed by a concise discussion on future directions.

8.
Diabetologia ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037604

RESUMO

AIMS/HYPOTHESIS: The relationship between metabolic dysfunction-associated steatotic liver disease (MASLD) and type 2 diabetes mellitus, insulin resistance and the metabolic syndrome is well established. While zinc finger BED-type containing 3 (ZBED3) has been linked to type 2 diabetes mellitus and the metabolic syndrome, its role in MASLD remains unclear. In this study, we aimed to investigate the function of ZBED3 in the context of MASLD. METHODS: Expression levels of ZBED3 were assessed in individuals with MASLD, as well as in cellular and animal models of MASLD. In vitro and in vivo analyses were conducted using a cellular model of MASLD induced by NEFA and an animal model of MASLD induced by a high-fat diet (HFD), respectively, to investigate the role of ZBED3 in MASLD. ZBED3 expression was increased by lentiviral infection or tail-vein injection of adeno-associated virus. RNA-seq and bioinformatics analysis were employed to examine the pathways through which ZBED3 modulates lipid accumulation. Findings from these next-generation transcriptome sequencing studies indicated that ZBED3 controls SREBP1c (also known as SREBF1; a gene involved in fatty acid de novo synthesis); thus, co-immunoprecipitation and LC-MS/MS were utilised to investigate the molecular mechanisms by which ZBED3 regulates the sterol regulatory element binding protein 1c (SREBP1c). RESULTS: In this study, we found that ZBED3 was significantly upregulated in the liver of individuals with MASLD and in MASLD animal models. ZBED3 overexpression promoted NEFA-induced triglyceride accumulation in hepatocytes in vitro. Furthermore, the hepatocyte-specific overexpression of Zbed3 promoted hepatic steatosis. Conversely, the hepatocyte-specific knockout of Zbed3 resulted in resistance of HFD-induced hepatic steatosis. Mechanistically, ZBED3 interacts directly with polypyrimidine tract-binding protein 1 (PTBP1) and affects its binding to the SREBP1c mRNA precursor to regulate SREBP1c mRNA stability and alternative splicing. CONCLUSIONS/INTERPRETATION: This study indicates that ZBED3 promotes hepatic steatosis and serves as a critical regulator of the progression of MASLD. DATA AVAILABILITY: RNA-seq data have been deposited in the NCBI Gene Expression Omnibus ( www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE231875 ). MS proteomics data have been deposited to the ProteomeXchange Consortium via the iProX partner repository ( https://proteomecentral.proteomexchange.org/cgi/GetDataset?ID=PXD041743 ).

9.
Eur J Neurosci ; 59(9): 2391-2402, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38314647

RESUMO

The brain's dynamic spontaneous neural activity is significant in supporting cognition; however, how brain dynamics go awry in subjective cognitive decline (SCD) and mild cognitive impairment (MCI) remains unclear. Thus, the current study aimed to investigate the dynamic amplitude of low-frequency fluctuation (dALFF) alterations in patients at high risk for Alzheimer's disease and to explore its correlation with clinical cognitive assessment scales, to identify an early imaging sign for these special populations. A total of 152 participants, including 72 SCD patients, 44 MCI patients and 36 healthy controls (HCs), underwent a resting-state functional magnetic resonance imaging and were assessed with various neuropsychological tests. The dALFF was measured using sliding-window analysis. We employed canonical correlation analysis (CCA) to examine the bi-multivariate correlations between neuropsychological scales and altered dALFF among multiple regions in SCD and MCI patients. Compared to those in the HC group, both the MCI and SCD groups showed higher dALFF values in the right opercular inferior frontal gyrus (voxel P < .001, cluster P < .05, correction). Moreover, the CCA models revealed that behavioural tests relevant to inattention correlated with the dALFF of the right middle frontal gyrus and right opercular inferior frontal gyrus, which are involved in frontoparietal networks (R = .43, P = .024). In conclusion, the brain dynamics of neural activity in frontal areas provide insights into the shared neural basis underlying SCD and MCI.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Imageamento por Ressonância Magnética , Humanos , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/diagnóstico por imagem , Masculino , Feminino , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/diagnóstico por imagem , Idoso , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem
10.
Anal Chem ; 96(14): 5499-5508, 2024 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-38547315

RESUMO

Characterizing the profiles of proteome and metabolome at the single-cell level is of great significance in single-cell multiomic studies. Herein, we proposed a novel strategy called one-shot single-cell proteome and metabolome analysis (scPMA) to acquire the proteome and metabolome information in a single-cell individual in one injection of LC-MS/MS analysis. Based on the scPMA strategy, a total workflow was developed to achieve the single-cell capture, nanoliter-scale sample pretreatment, one-shot LC injection and separation of the enzyme-digested peptides and metabolites, and dual-zone MS/MS detection for proteome and metabolome profiling. Benefiting from the scPMA strategy, we realized dual-omic analysis of single tumor cells, including A549, HeLa, and HepG2 cells with 816, 578, and 293 protein groups and 72, 91, and 148 metabolites quantified on average. A single-cell perspective experiment for investigating the doxorubicin-induced antitumor effects in both the proteome and metabolome aspects was also performed.


Assuntos
Proteoma , Espectrometria de Massas em Tandem , Humanos , Proteoma/metabolismo , Cromatografia Líquida , Metaboloma , Células HeLa
11.
Small ; 20(3): e2300733, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37452437

RESUMO

Relapse and unresectability have become the main obstacle for further improving hepatocellular carcinoma (HCC) treatment effect. Currently, single therapy for HCC in clinical practice is limited by postoperative recurrence, intraoperative blood loss and poor patient outcomes. Multidisciplinary therapy has been recognized as the key to improving the long-term survival rate for HCC. However, the clinical application of HCC synthetic therapy is restricted by single functional biomaterials. In this study, a magnetic nanocomposite hydrogel (CG-IM) with iron oxide nanoparticle-loaded mica nanosheets (Iron oxide nanoparticles@Mica, IM) is reported. This biocompatible magnetic hydrogel integrated high injectability, magnetocaloric property, mechanical robustness, wet adhesion, and hemostasis, leading to efficient HCC multidisciplinary therapies including postoperative tumor margin treatment and percutaneous locoregional ablation. After minimally invasive hepatectomy of HCC, the CG-IM hydrogel can facilely seal the bleeding hepatic margin, followed by magnetic hyperthermia ablation to effectively prevent recurrence. In addition, CG-IM hydrogel can inhibit unresectable HCC by magnetic hyperthermia through the percutaneous intervention under ultrasound guidance.


Assuntos
Silicatos de Alumínio , Carcinoma Hepatocelular , Hipertermia Induzida , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Neoplasias Hepáticas/patologia , Hidrogéis/farmacologia , Fenômenos Magnéticos
12.
Magn Reson Med ; 92(2): 761-771, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38523590

RESUMO

PURPOSE: This study evaluated the velocity-selective (VS) MRA with different VS labeling modules, including double refocused hyperbolic tangent, eight-segment B1-insensitive rotation, delay alternating with nutation for tailored excitation, Fourier transform-based VS saturation, and Fourier transform-based inversion. METHODS: These five VS labeling modules were evaluated first through Bloch simulations, and then using VSMRA directly on various cerebral arteries of healthy subjects. The relative signal ratios from arterial ROIs and surrounding tissues as well as relative arteria-tissue contrast ratios of different methods were compared. RESULTS: Double refocused hyperbolic tangent and eight-segment B1-insensitive rotation showed very similar labeling effects. Delay alternating with nutation for tailored excitation yielded high arterial signal but with residual tissue signal due to the spatial banding effect. Fourier transform-based VS saturation with half the time of other techniques serves as an efficient nonsubtractive VSMRA method, but the remaining tissue signal still obscured some small distal arteries that were delineated by other subtraction-based VSMRA, allowing more complete cancelation of static tissue. Fourier transform-based inversion produced the highest arterial signal in VSMRA with minimal tissue background. CONCLUSION: This is the first study that angiographically compared five different VS labeling modules. Their labeling characteristics on arteries and tissue and implications for VSMRA and VS arterial spin labeling are discussed.


Assuntos
Artérias Cerebrais , Análise de Fourier , Angiografia por Ressonância Magnética , Humanos , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/fisiologia , Angiografia por Ressonância Magnética/métodos , Adulto , Masculino , Feminino , Algoritmos , Velocidade do Fluxo Sanguíneo/fisiologia , Marcadores de Spin , Angiografia Cerebral/métodos , Circulação Cerebrovascular/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Interpretação de Imagem Assistida por Computador/métodos
13.
Magn Reson Med ; 92(5): 2065-2073, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38852173

RESUMO

PURPOSE: Velocity selective arterial spin labeling (VSASL) quantification assumes that the labeled bolus continuously moves into the imaging voxel during the post-labeling delay (PLD). Faster blood flow could lead to a bolus duration shorter than the applied PLD of VSASL and cause underestimation of cerebral blood flow (CBF). This study aims to evaluate the performance of velocity-selective inversion (VSI) prepared arterial spin labeling (ASL) with different PLDs and pseudo-continuous ASL (PCASL) for quantification of hypercapnia-induced cerebrovascular reactivity (CVR), using phase-contrast (PC) MRI as a global reference. METHODS: We compared CVR obtained by VSI-ASL with PLD of 1520 ms (VSASL-1520), 1000 ms (VSASL-1000), and 500 ms (VSASL-500), PCASL with PLD of 1800 ms (PCASL-1800), and PC MRI on eight healthy volunteers at two sessions. RESULTS: Compared with PC MRI, VSASL-1520 produced significantly lower global CVR values, while PCASL-1800, VSASL-1000, and VSASL-500 yielded more consistent results. The reduced CVR in VSASL-1520 was more pronounced in carotid territories including frontal and temporal lobes than in vertebral territories such as the occipital lobe. This is largely caused by the underestimated perfusion during hypercapnia due to the reduced bolus duration being less than the PLD. CONCLUSION: Although VSASL offers certain advantages over spatially selective ASL due to its reduced susceptibility to delayed ATT, this technique is prone to biases when the ATT is excessively short. Therefore, a short PLD should be employed for reliable perfusion and CVR quantification in populations or conditions with fast flow.


Assuntos
Encéfalo , Circulação Cerebrovascular , Hipercapnia , Imageamento por Ressonância Magnética , Marcadores de Spin , Humanos , Circulação Cerebrovascular/fisiologia , Masculino , Adulto , Feminino , Velocidade do Fluxo Sanguíneo , Hipercapnia/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Imageamento por Ressonância Magnética/métodos , Voluntários Saudáveis , Adulto Jovem , Processamento de Imagem Assistida por Computador/métodos
14.
Magn Reson Med ; 91(3): 942-954, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37899691

RESUMO

PURPOSE: To confirm that CrCEST in muscle exhibits a slow-exchanging process, and to obtain high-resolution amide, creatine (Cr), and phosphocreatine (PCr) maps of skeletal muscle using a POlynomial and Lorentzian Line-shape Fitting (PLOF) CEST at 3T. METHODS: We used dynamic changes in PCr/CrCEST of mouse hindlimb before and after euthanasia to assign the Cr and PCr CEST peaks in the Z-spectrum at 3T and to obtain the optimum saturation parameters. Segmented 3D EPI was employed to obtain multi-slice amide, PCr, and Cr CEST maps of human skeletal muscle. Subsequently, the PCrCEST maps were calibrated using the PCr concentrations determined by 31 P MRS. RESULTS: A comparison of the Z-spectra in mouse hindlimb before and after euthanasia indicated that CrCEST is a slow-exchanging process in muscle (<150.7 s-1 ). This allowed us to simultaneously extract PCr/CrCEST signals at 3T using the PLOF method. We determined optimal B1 values ranging from 0.3 to 0.6 µT for CrCEST in muscle and 0.3-1.2 µT for PCrCEST. For the study on human calf muscle, we determined an optimum saturation time of 2 s for both PCr/CrCEST (B1 = 0.6 µT). The PCr/CrCEST using 3D EPI were found to be comparable to those obtained using turbo spin echo (TSE). (3D EPI/TSE PCr: (2.6 ± 0.3) %/(2.3 ± 0.1) %; Cr: (1.3 ± 0.1) %/(1.4 ± 0.07) %). CONCLUSIONS: Our study showed that in vivo CrCEST is a slow-exchanging process. Hence, amide, Cr, and PCr CEST in the skeletal muscle can be mapped simultaneously at 3T by PLOF CEST.


Assuntos
Creatina , Imageamento por Ressonância Magnética , Humanos , Animais , Camundongos , Fosfocreatina , Imageamento por Ressonância Magnética/métodos , Músculo Esquelético/diagnóstico por imagem , Amidas
15.
Magn Reson Med ; 92(4): 1456-1470, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38748853

RESUMO

PURPOSE: To develop a 3D, high-sensitivity CEST mapping technique based on the 3D stack-of-spirals (SOS) gradient echo readout, the proposed approach was compared with conventional acquisition techniques and evaluated for its efficacy in concurrently mapping of guanidino (Guan) and amide CEST in human brain at 3 T, leveraging the polynomial Lorentzian line-shape fitting (PLOF) method. METHODS: Saturation time and recovery delay were optimized to achieve maximum CEST time efficiency. The 3DSOS method was compared with segmented 3D EPI (3DEPI), turbo spin echo, and gradient- and spin-echo techniques. Image quality, temporal SNR (tSNR), and test-retest reliability were assessed. Maps of Guan and amide CEST derived from 3DSOS were demonstrated on a low-grade glioma patient. RESULTS: The optimized recovery delay/saturation time was determined to be 1.4/2 s for Guan and amide CEST. In addition to nearly doubling the slice number, the gradient echo techniques also outperformed spin echo sequences in tSNR: 3DEPI (193.8 ± 6.6), 3DSOS (173.9 ± 5.6), and GRASE (141.0 ± 2.7). 3DSOS, compared with 3DEPI, demonstrated comparable GuanCEST signal in gray matter (GM) (3DSOS: [2.14%-2.59%] vs. 3DEPI: [2.15%-2.61%]), and white matter (WM) (3DSOS: [1.49%-2.11%] vs. 3DEPI: [1.64%-2.09%]). 3DSOS also achieves significantly higher amideCEST in both GM (3DSOS: [2.29%-3.00%] vs. 3DEPI: [2.06%-2.92%]) and WM (3DSOS: [2.23%-2.66%] vs. 3DEPI: [1.95%-2.57%]). 3DSOS outperforms 3DEPI in terms of scan-rescan reliability (correlation coefficient: 3DSOS: 0.58-0.96 vs. 3DEPI: -0.02 to 0.75) and robustness to motion as well. CONCLUSION: The 3DSOS CEST technique shows promise for whole-cerebrum CEST imaging, offering uniform contrast and robustness against motion artifacts.


Assuntos
Amidas , Encéfalo , Imageamento Tridimensional , Imageamento por Ressonância Magnética , Humanos , Amidas/química , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Reprodutibilidade dos Testes , Imagem Ecoplanar/métodos , Glioma/diagnóstico por imagem , Algoritmos , Razão Sinal-Ruído , Neoplasias Encefálicas/diagnóstico por imagem , Adulto , Processamento de Imagem Assistida por Computador/métodos , Masculino , Feminino , Guanidina/química
16.
Magn Reson Med ; 92(2): 469-495, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38594906

RESUMO

Accurate assessment of cerebral perfusion is vital for understanding the hemodynamic processes involved in various neurological disorders and guiding clinical decision-making. This guidelines article provides a comprehensive overview of quantitative perfusion imaging of the brain using multi-timepoint arterial spin labeling (ASL), along with recommendations for its acquisition and quantification. A major benefit of acquiring ASL data with multiple label durations and/or post-labeling delays (PLDs) is being able to account for the effect of variable arterial transit time (ATT) on quantitative perfusion values and additionally visualize the spatial pattern of ATT itself, providing valuable clinical insights. Although multi-timepoint data can be acquired in the same scan time as single-PLD data with comparable perfusion measurement precision, its acquisition and postprocessing presents challenges beyond single-PLD ASL, impeding widespread adoption. Building upon the 2015 ASL consensus article, this work highlights the protocol distinctions specific to multi-timepoint ASL and provides robust recommendations for acquiring high-quality data. Additionally, we propose an extended quantification model based on the 2015 consensus model and discuss relevant postprocessing options to enhance the analysis of multi-timepoint ASL data. Furthermore, we review the potential clinical applications where multi-timepoint ASL is expected to offer significant benefits. This article is part of a series published by the International Society for Magnetic Resonance in Medicine (ISMRM) Perfusion Study Group, aiming to guide and inspire the advancement and utilization of ASL beyond the scope of the 2015 consensus article.


Assuntos
Encéfalo , Circulação Cerebrovascular , Marcadores de Spin , Humanos , Encéfalo/diagnóstico por imagem , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular/fisiologia , Processamento de Imagem Assistida por Computador/métodos , Angiografia por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/métodos , Imagem de Perfusão
17.
Mol Phylogenet Evol ; 190: 107961, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37918684

RESUMO

The tribe Potentilleae comprises approximately 1700 species in 13 genera, making it one of the largest of the 16 tribes in Rosaceae. Our understanding of the composition and relationships among members of Potentilleae has advanced dramatically with the application of molecular markers in the last two decades. Yet there is still much work remaining toward a robust phylogenetic framework for the entire Potentilleae and a comprehensive genus-level dating framework for the tribe. The goals of the present study were to establish a phylogenetic framework for Potentilleae, infer the origin and diversification of the tribe using a temporal framework, and explore the taxonomic implications in light of the updated phylogenetic framework. We used the plastome sequences from 158 accessions representing 139 taxa covering all 13 recognized genera of the tribe to reconstruct the Potentilleae phylogeny. High phylogenetic resolution was recovered along the Potentilleae backbone. Two major clades were recovered within Potentilleae, corresponding to the two subtribes Fragariinae and Potentillinae. Within Fragariinae, two subclades were recovered. In one subclade, Sibbaldia sensu stricto is sister to a clade containing Sibbaldianthe, Comarum, Farinopsis, and Alchemilla sensu lato. In the other subclade, Fragaria is sister to a clade comprising Chamaerhodos, Chamaecallis, Drymocallis, Dasiphora, and Potaninia. Within Potentillinae, Argentina is sister to Potentilla sensu stricto. Within Potentilla sensu stricto, clade Himalaya is sister to Alba, and the Himalaya-Alba clade together is sister to a clade comprising Reptans, Potentilla ancistrifolia Bunge, Fragarioides, Ivesioid, and Argentea. Divergence time estimates indicated that tribe Potentilleae originated during the middle Eocene, and subtribes Fragariinae and Potentillinae diverged around the Eocene-Oligocene transition, and divergence times dated for Potentilleae genera ranged from the early Miocene to the late Pleistocene.


Assuntos
Rosaceae , Filogenia , Plastídeos/genética , Argentina
18.
Cell Commun Signal ; 22(1): 208, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566066

RESUMO

This review presents a comprehensive exploration of the pivotal role played by the Linker of Nucleoskeleton and Cytoskeleton (LINC) complex, with a particular focus on Nesprin proteins, in cellular mechanics and the pathogenesis of muscular diseases. Distinguishing itself from prior works, the analysis delves deeply into the intricate interplay of the LINC complex, emphasizing its indispensable contribution to maintaining cellular structural integrity, especially in mechanically sensitive tissues such as cardiac and striated muscles. Additionally, the significant association between mutations in Nesprin proteins and the onset of Dilated Cardiomyopathy (DCM) and Emery-Dreifuss Muscular Dystrophy (EDMD) is highlighted, underscoring their pivotal role in disease pathogenesis. Through a comprehensive examination of DCM and EDMD cases, the review elucidates the disruptions in the LINC complex, nuclear morphology alterations, and muscular developmental disorders, thus emphasizing the essential function of an intact LINC complex in preserving muscle physiological functions. Moreover, the review provides novel insights into the implications of Nesprin mutations for cellular dynamics in the pathogenesis of muscular diseases, particularly in maintaining cardiac structural and functional integrity. Furthermore, advanced therapeutic strategies, including rectifying Nesprin gene mutations, controlling Nesprin protein expression, enhancing LINC complex functionality, and augmenting cardiac muscle cell function are proposed. By shedding light on the intricate molecular mechanisms underlying nuclear-cytoskeletal interactions, the review lays the groundwork for future research and therapeutic interventions aimed at addressing genetic muscle disorders.


Assuntos
Doenças Musculares , Distrofia Muscular de Emery-Dreifuss , Humanos , Membrana Nuclear/metabolismo , Membrana Nuclear/patologia , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Doenças Musculares/metabolismo , Citoesqueleto/metabolismo , Distrofia Muscular de Emery-Dreifuss/genética , Distrofia Muscular de Emery-Dreifuss/metabolismo , Distrofia Muscular de Emery-Dreifuss/patologia
19.
Anticancer Drugs ; 35(1): 81-85, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37227031

RESUMO

Perihilar cholangiocarcinoma is a refractory malignancy with an unfavorable prognosis and a high probability of recurrence. Systemic chemotherapy is critical for palliative treatment, but effective therapeutic strategies for perihilar cholangiocarcinoma after first-line chemotherapy failure are scarce. Here, we introduced a sustained benefit following sintilimab combined with lenvatinib plus S-1 in a patient with recurrent perihilar cholangiocarcinoma. A 52-year-old female patient was admitted to our hospital due to yellow skin and sclera, and further radiological examination revealed perihilar cholangiocarcinoma. The patient underwent surgery and histopathological results confirmed moderately differentiated adenocarcinoma with metastatic lymph nodes. Postoperative adjuvant chemotherapy with gemcitabine and S-1 was given. One year after surgery, the patient experienced hepatic recurrence. Then, she received radiofrequency ablation combined with gemcitabine and cisplatin. Unfortunately, radiological assessment revealed progressive disease with multiple liver metastases after treatment. Subsequently, she received sintilimab combined with lenvatinib plus S-1 and the lesions were completely regressed following 14 cycles of combination therapy. The patient recovered well without disease recurrence at the last follow-up. Sintilimab combined with lenvatinib plus S-1 may be an alternative therapeutic option for chemotherapy-refractory perihilar cholangiocarcinoma, and further evaluation in a larger number of patients is needed.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Feminino , Humanos , Pessoa de Meia-Idade , Tumor de Klatskin/tratamento farmacológico , Tumor de Klatskin/patologia , Tumor de Klatskin/cirurgia , Gencitabina , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Resposta Patológica Completa , Ductos Biliares Intra-Hepáticos/patologia , Ductos Biliares Intra-Hepáticos/cirurgia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/cirurgia , Neoplasias dos Ductos Biliares/patologia
20.
J Org Chem ; 89(7): 5200-5206, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38500359

RESUMO

A regiodivergent allylation of 1H-indoles highly selectively at the C3 and N1 positions with ß-acyl allylic sulfides through desulfurative C-C/C-N bond-forming reactions has been developed under mild conditions. Notably, the remarkable site-selective switch can be achieved by a delicate choice of solvents and bases. This cost-efficient method displays a broad substrate scope, good functional compatibility, and excellent site-selectivity, thus offering a divergent synthesis of indole substituted α-branched enones, which possess diverse potential opportunities for further applications and derivatization.

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