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1.
Plant Cell ; 35(2): 795-807, 2023 02 20.
Artigo em Inglês | MEDLINE | ID: mdl-36471570

RESUMO

Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) performs most of the carbon fixation on Earth. However, plant Rubisco is an intrinsically inefficient enzyme given its low carboxylation rate, representing a major limitation to photosynthesis. Replacing endogenous plant Rubisco with a faster Rubisco is anticipated to enhance crop photosynthesis and productivity. However, the requirement of chaperones for Rubisco expression and assembly has obstructed the efficient production of functional foreign Rubisco in chloroplasts. Here, we report the engineering of a Form 1A Rubisco from the proteobacterium Halothiobacillus neapolitanus in Escherichia coli and tobacco (Nicotiana tabacum) chloroplasts without any cognate chaperones. The native tobacco gene encoding Rubisco large subunit was genetically replaced with H. neapolitanus Rubisco (HnRubisco) large and small subunit genes. We show that HnRubisco subunits can form functional L8S8 hexadecamers in tobacco chloroplasts at high efficiency, accounting for ∼40% of the wild-type tobacco Rubisco content. The chloroplast-expressed HnRubisco displayed a ∼2-fold greater carboxylation rate and supported a similar autotrophic growth rate of transgenic plants to that of wild-type in air supplemented with 1% CO2. This study represents a step toward the engineering of a fast and highly active Rubisco in chloroplasts to improve crop photosynthesis and growth.


Assuntos
Nicotiana , Ribulose-Bifosfato Carboxilase , Nicotiana/metabolismo , Ribulose-Bifosfato Carboxilase/genética , Ribulose-Bifosfato Carboxilase/metabolismo , Fotossíntese/genética , Cloroplastos/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Dióxido de Carbono/metabolismo
2.
Plant Cell ; 35(7): 2449-2463, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-36943796

RESUMO

Cryptophyte plastids originated from a red algal ancestor through secondary endosymbiosis. Cryptophyte photosystem I (PSI) associates with transmembrane alloxanthin-chlorophyll a/c proteins (ACPIs) as light-harvesting complexes (LHCs). Here, we report the structure of the photosynthetic PSI-ACPI supercomplex from the cryptophyte Chroomonas placoidea at 2.7-Å resolution obtained by crygenic electron microscopy. Cryptophyte PSI-ACPI represents a unique PSI-LHCI intermediate in the evolution from red algal to diatom PSI-LHCI. The PSI-ACPI supercomplex is composed of a monomeric PSI core containing 14 subunits, 12 of which originated in red algae, 1 diatom PsaR homolog, and an additional peptide. The PSI core is surrounded by 14 ACPI subunits that form 2 antenna layers: an inner layer with 11 ACPIs surrounding the PSI core and an outer layer containing 3 ACPIs. A pigment-binding subunit that is not present in any other previously characterized PSI-LHCI complexes, ACPI-S, mediates the association and energy transfer between the outer and inner ACPIs. The extensive pigment network of PSI-ACPI ensures efficient light harvesting, energy transfer, and dissipation. Overall, the PSI-LHCI structure identified in this study provides a framework for delineating the mechanisms of energy transfer in cryptophyte PSI-LHCI and for understanding the evolution of photosynthesis in the red lineage, which occurred via secondary endosymbiosis.


Assuntos
Diatomáceas , Complexos de Proteínas Captadores de Luz , Complexos de Proteínas Captadores de Luz/metabolismo , Clorofila A/metabolismo , Complexo de Proteína do Fotossistema I/metabolismo , Fotossíntese , Transferência de Energia , Diatomáceas/metabolismo
3.
Immunity ; 46(3): 446-456, 2017 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-28314593

RESUMO

Zika virus (ZIKV) has become a public health threat due to its global transmission and link to severe congenital disorders. The host immune responses to ZIKV infection have not been fully elucidated, and effective therapeutics are not currently available. Herein, we demonstrated that cholesterol-25-hydroxylase (CH25H) was induced in response to ZIKV infection and that its enzymatic product, 25-hydroxycholesterol (25HC), was a critical mediator of host protection against ZIKV. Synthetic 25HC addition inhibited ZIKV infection in vitro by blocking viral entry, and treatment with 25HC reduced viremia and conferred protection against ZIKV in mice and rhesus macaques. 25HC suppressed ZIKV infection and reduced tissue damage in human cortical organoids and the embryonic brain of the ZIKV-induced mouse microcephaly model. Our findings highlight the protective role of CH25H during ZIKV infection and the potential use of 25HC as a natural antiviral agent to combat ZIKV infection and prevent ZIKV-associated outcomes, such as microcephaly.


Assuntos
Antivirais/farmacologia , Hidroxicolesteróis/farmacologia , Microcefalia/virologia , Infecção por Zika virus/complicações , Animais , Encéfalo/efeitos dos fármacos , Modelos Animais de Doenças , Imunofluorescência , Humanos , Macaca mulatta , Camundongos , Microscopia Confocal , Internalização do Vírus/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Zika virus/fisiologia
4.
Nat Immunol ; 14(2): 172-8, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23222971

RESUMO

DDX41 is a sensor of intracellular double-stranded DNA (dsDNA) in myeloid dendritic cells (mDCs) that triggers a type I interferon response via the signaling adaptor STING. We identified the E3 ligase TRIM21 as a DDX41-interacting protein and found that knockdown of or deficiency in TRIM21 resulted in enhanced type I interferon responses to intracellular dsDNA and DNA viruses. Overexpression of TRIM21 resulted in more degradation of DDX41 and less production of interferon-ß (IFN-ß) in response to intracellular dsDNA. The SPRY-PRY domain of TRIM21 interacted with the DEADc domain of DDX41. Lys9 and Lys115 of DDX41 were the targets of TRIM21-mediated ubiquitination. TRIM21 is therefore an interferon-inducible E3 ligase that induces the Lys48 (K48)-linked ubiquitination and degradation of DDX41 and negatively regulates the innate immune response to intracellular dsDNA.


Assuntos
DNA Viral/imunologia , DNA/imunologia , Células Dendríticas/imunologia , Imunidade Inata , Ribonucleoproteínas/imunologia , Animais , DNA/genética , DNA Viral/genética , Células Dendríticas/patologia , Células Dendríticas/virologia , Regulação da Expressão Gênica , Interferon beta/biossíntese , Interferon beta/imunologia , Lisina/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Camundongos Transgênicos , Orthoreovirus de Mamíferos/fisiologia , Estrutura Terciária de Proteína , Proteólise , Ribonucleoproteínas/deficiência , Ribonucleoproteínas/genética , Transdução de Sinais/imunologia , Ubiquitinação , Vesiculovirus/fisiologia
5.
Plant Physiol ; 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39172695

RESUMO

The carboxysome is a natural proteinaceous organelle for carbon fixation in cyanobacteria and chemoautotrophs. It comprises hundreds of protein homologs that self-assemble to form a polyhedral shell structure to sequester cargo enzymes, ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) and carbonic anhydrases. How these protein components assemble to construct a functional carboxysome is a central question in not only understanding carboxysome structure and function but also synthetic engineering of carboxysomes for biotechnological applications. Here, we determined the structure of the chaperone protein CcmS, which has recently been identified to be involved in ß-carboxysome assembly, and its interactions with ß-carboxysome proteins. The crystal structure at 1.99 Å resolution reveals CcmS from Nostoc sp. PCC 7120 forms a homodimer, and each CcmS monomer consists of five α-helices and four ß-sheets. Biochemical assays indicate that CcmS specifically interacts with the C-terminal extension of the carboxysome shell protein CcmK1, but not the shell protein homolog CcmK2 or the carboxysome scaffolding protein CcmM. Moreover, we solved the structure of a stable complex of CcmS and the C-terminus of CcmK1 at 1.67 Å resolution and unveiled how the CcmS dimer interacts with the C-terminus of CcmK1. These findings allowed us to propose a model to illustrate CcmS-mediated ß-carboxysome assembly by interacting with CcmK1 at the outer shell surface. Collectively, our study provides detailed insights into the accessory factors that drive and regulate carboxysome assembly, thereby improving our knowledge of carboxysome structure, function, and bioengineering.

6.
Annu Rev Microbiol ; 74: 633-654, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32689916

RESUMO

Photosynthetic membranes are typically densely packed with proteins, and this is crucial for their function in efficient trapping of light energy. Despite being crowded with protein, the membranes are fluid systems in which proteins and smaller molecules can diffuse. Fluidity is also crucial for photosynthetic function, as it is essential for biogenesis, electron transport, and protein redistribution for functional regulation. All photosynthetic membranes seem to maintain a delicate balance between crowding, order, and fluidity. How does this work in phototrophic bacteria? In this review, we focus on two types of intensively studied bacterial photosynthetic membranes: the chromatophore membranes of purple bacteria and the thylakoid membranes of cyanobacteria. Both systems are distinct from the plasma membrane, and both have a distinctive protein composition that reflects their specialized roles. Chromatophores are formed from plasma membrane invaginations, while thylakoid membranes appear to be an independent intracellular membrane system. We discuss the techniques that can be applied to study the organization and dynamics of these membrane systems, including electron microscopy techniques, atomic force microscopy, and many variants of fluorescence microscopy. We go on to discuss the insights that havebeen acquired from these techniques, and the role of membrane dynamics in the physiology of photosynthetic membranes. Membrane dynamics on multiple timescales are crucial for membrane function, from electron transport on timescales of microseconds to milliseconds to regulation and biogenesis on timescales of minutes to hours. We emphasize the open questions that remain in the field.


Assuntos
Cromatóforos Bacterianos/metabolismo , Cianobactérias/metabolismo , Fotossíntese/fisiologia , Tilacoides/metabolismo , Cianobactérias/química , Cianobactérias/genética , Transporte de Elétrons , Microscopia/classificação , Microscopia/métodos , Fotossíntese/genética , Tilacoides/química
7.
Nano Lett ; 24(26): 8063-8070, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38888216

RESUMO

The basal plane of transition metal dichalcogenides (TMDCs) is inert for the hydrogen evolution reaction (HER) due to its low-efficiency charge transfer kinetics. We propose a strategy of filling the van der Waals (vdW) layer with delocalized electrons to enable vertical penetration of electrons from the collector to the adsorption intermediate vertically. Guided by density functional theory, we achieve this concept by incorporating Cu atoms into the interlayers of tantalum disulfide (TaS2). The delocalized electrons of d-orbitals of the interlayered Cu can constitute the charge transfer pathways in the vertical direction, thus overcoming the hopping migration through vdW gaps. The vertical conductivity of TaS2 increased by 2 orders of magnitude. The TaS2 basal plane HER activity was extracted with an on-chip microcell. Modified by the delocalized electrons, the current density increased by 20 times, reaching an ultrahigh value of 800 mA cm-2 at -0.4 V without iR compensation.

8.
Breast Cancer Res ; 26(1): 116, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39010116

RESUMO

BACKGROUND: Higher mammographic density (MD), a radiological measure of the proportion of fibroglandular tissue in the breast, and lower terminal duct lobular unit (TDLU) involution, a histological measure of the amount of epithelial tissue in the breast, are independent breast cancer risk factors. Previous studies among predominantly white women have associated reduced TDLU involution with higher MD. METHODS: In this cohort of 611 invasive breast cancer patients (ages 23-91 years [58.4% ≥ 50 years]) from China, where breast cancer incidence rates are lower and the prevalence of dense breasts is higher compared with Western countries, we examined the associations between TDLU involution assessed in tumor-adjacent normal breast tissue and quantitative MD assessed in the contralateral breast obtained from the VolparaDensity software. Associations were estimated using generalized linear models with MD measures as the outcome variables (log-transformed), TDLU measures as explanatory variables (categorized into quartiles or tertiles), and adjusted for age, body mass index, parity, age at menarche and breast cancer subtype. RESULTS: We found that, among all women, percent dense volume (PDV) was positively associated with TDLU count (highest tertile vs. zero: Expbeta = 1.28, 95% confidence interval [CI] 1.08-1.51, ptrend = < .0001), TDLU span (highest vs. lowest tertile: Expbeta = 1.23, 95% CI 1.11-1.37, ptrend = < .0001) and acini count/TDLU (highest vs. lowest tertile: Expbeta = 1.22, 95% CI 1.09-1.37, ptrend = 0.0005), while non-dense volume (NDV) was inversely associated with these measures. Similar trend was observed for absolute dense volume (ADV) after the adjustment of total breast volume, although the associations for ADV were in general weaker than those for PDV. The MD-TDLU associations were generally more pronounced among breast cancer patients ≥ 50 years and those with luminal A tumors compared with patients < 50 years and with luminal B tumors. CONCLUSIONS: Our findings based on quantitative MD and TDLU involution measures among Chinese breast cancer patients are largely consistent with those reported in Western populations and may provide additional insights into the complexity of the relationship, which varies by age, and possibly breast cancer subtype.


Assuntos
Densidade da Mama , Neoplasias da Mama , Mamografia , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias da Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/epidemiologia , Adulto , Idoso , China/epidemiologia , Mamografia/métodos , Idoso de 80 Anos ou mais , Adulto Jovem , Fatores de Risco , Mama/diagnóstico por imagem , Mama/patologia , Glândulas Mamárias Humanas/diagnóstico por imagem , Glândulas Mamárias Humanas/patologia , Glândulas Mamárias Humanas/anormalidades , População do Leste Asiático
9.
Small ; : e2401736, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030958

RESUMO

As the rising renewable energy demands and lithium scarcity, developing high-capacity anode materials to improve the energy density of potassium-based batteries (PBBs) is increasingly crucial. In this work, a unique orderly multilayered growth (OMLG) mechanism on a 2D-Ca2Si monolayer is theoretically demonstrated for potassium storage by first-principles calculations. The global-energy-minimum Ca2Si monolayer is a semiconductor with isotropic mechanical properties and remarkable electrochemical properties, such as a low potassium ion migration energy barrier of 0.07 eV and a low open circuit voltage ranging from 0.224 to 0.003 V. Most notably, 2D-Ca2Si demonstrates an ultrahigh theoretical specific capacity of 5459 mAh g-1 and a total specific capacity of 610 mAh g-1, reaching up to 89% of the capacity of a potassium metal anode. Remarkably, the OMLG mechanism facilitates stable, dendrite-free deposition of hcp-K metal layers on the 2D-Ca2Si surface, where the ultrahigh and gradually converging lattice match as the layers increase is the key to achieving theoretically near-infinite growth. The study theoretically demonstrates the Ca2Si monolayer a highly promising anode material, and offers a novel potassium storage strategy for designing 2D anode materials with high specific capacity, rapid potassium-ion migration, and good safety.

10.
Small ; : e2406127, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39380391

RESUMO

The stability of perovskite solar cells is closely related to the defects in perovskite crystals, and a large number of crystal defects are caused by the solution method. In this study, resveratrol (RES), a green natural antioxidant abundant in knotweed and grape leaves, is introduced into perovskite films to passivate the defect. RES achieves defect passivation by interacting with uncoordinated Pb2+ in perovskite films. The defect formation energy of VPb and PbI on the surface of perovskite thin films is increased by RES doping, as calculated by density functional theory. The results show that the quality of the perovskite film is significantly improved, and the energy level structure of the device is optimized, and the power conversion efficiency (PCE) of the device is increased from 21.62% to 23.44%. RES can hinder the degradation of perovskite structures by O2 - free radicals, and the device retained 88% of its initial PCE after over 1000 h in pure oxygen environment. The device retains 91% of the initial PCE after >1000 h at 25 °C and 50 ± 5% relative humidity. This work provides an idea for the use of natural and environmentally friendly additives to improve the efficiency and stability of devices.

11.
Opt Express ; 32(3): 3561-3573, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38297574

RESUMO

Monochromatic light-illuminated active-imaging stereo-digital image correlation (stereo-DIC) has been extensively used for measuring the surface deformation of materials and structures at elevated temperatures. Despite the improvements in the image acquisition techniques or devices, it is still challenging to measure the 3D deformation of materials and structures in the presence of strong, time-varying ambient light and thermal radiation. In this study, we present what we believe to be a novel dual-filtering single-camera stereo-DIC technique for full-field 3D high-temperature deformation measurement, even in the case of extremely intense ambient light and thermal radiation. In contrast to conventional active-imaging stereo-DIC that only suppresses the thermal radiations in the spectral domain, the proposed technique utilized a dual-filtering strategy (i.e., narrow bandpass optical filtering and ultrashort exposing) to suppress the strong ambient light and thermal radiation in both time and spectral domains. Besides, a four-mirror adapter is adopted to realize 3D shape and deformation measurement using a compact single time-gated camera. Experimental verifications, including assessments with laboratory experiments and validations on real thermal deformation tests under transient aerodynamic heating and direct ohmic heating, convincingly demonstrated that the proposed single-camera dual-filtering stereo-DIC method can achieve accurate 3D shape, motion and deformation measurement, even with strong light and thermal radiation from the quartz lamps and the heated sample.

12.
Chemistry ; : e202402402, 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39186035

RESUMO

Efficient transition-metal-free synthesis of benzo[b]azepines and oxindoles is achieved via a radical relay cascade strategy employing halogen atom transfer (XAT) for aryl radical generation followed by intramolecular hydrogen atom transfer (HAT). Optimization yielded moderate to substantial yields under visible light irradiation. Preliminary biological assessments revealed promising anti-tumor activity for select compounds. This study underscores the potential of XAT-mediated radical relay cascades in medicinal chemistry and anticancer drug discovery.

13.
Ann Hematol ; 103(7): 2445-2454, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38605231

RESUMO

BACKGROUND: Real-world data on outcomes of upfront allogeneic hematopoietic stem cell transplantation (allo-HCT) for adult T-cell acute lymphoblastic leukemia/lymphoma (T-ALL) patients in first complete remission (CR1) is still lacking. METHODS: A single center retrospective study was conducted from 94 consecutive patients received their first allo-HCT between 2010 and 2021, which include 76 patients received upfront allo-HCT and 18 patients received allo-HCT in non-upfront settings. RESULTS: There were no significant differences in most variables. In the upfront allo-HCT group, 52 (68%) patients achieved CR1 with one cycle of induction regimen. 24 (32%) patients achieved CR1 with more than one cycle. In the non-upfront group, there were 14 patients with active disease and 4 patients in second CR before transplant. The majority of patients received antithymocyte globulin-based graft-versus-host disease prophylaxis. Median follow-up time was 51 months for both groups. 5-year overall survival (OS) was 54% in the upfront allo-HCT group. While, in the non-upfront group, 5-year OS were 19% (P = 0.013). 5-year progression free survival in the upfront group was higher than that in the non-upfront group (50% versus 20%, P = 0.02). 5-year cumulative incidence relapse rate was significantly higher in non-upfront group (64% vs. 32%, P = 0.006). While, there was no difference in the 5-year non-relapse mortality (NRM) rate (19% versus 16%, P = 0.56). The most common cause of death was disease progression. In multivariable analysis, non-upfront allo-HCT (hazard ratios (HR) 2.14, P = 0.03) and HCT-CI (≥ 2) (HR 6.07, P = 0.002) were identified to be associated with worse OS. Non-upfront allo-HCT and HCT-CI (≥ 2) were also found to be independent risk factors for higher relapse rate. While, haploidentical-HCT was found to be associated with increased NRM. CONCLUSIONS: Our study indicated that allo-HCT remains an important curative treatment for adult patients with T-ALL, especially when it was performed in the upfront setting.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Indução de Remissão , Humanos , Adulto , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células T Precursoras/terapia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Adulto Jovem , Transplante Homólogo , Taxa de Sobrevida , Idoso , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/prevenção & controle , Adolescente , Aloenxertos , Leucemia-Linfoma de Células T do Adulto/terapia , Leucemia-Linfoma de Células T do Adulto/mortalidade , Seguimentos , Intervalo Livre de Doença
14.
Ther Drug Monit ; 46(5): 634-641, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38531816

RESUMO

BACKGROUND: Ibrutinib and zanubrutinib are Bruton tyrosine kinase inhibitors used to treat mantle cell lymphoma, chronic lymphocytic leukemia, and small lymphocytic lymphoma. Dihydroxydiol ibrutinib (DHI) is an active metabolite of the drug. A liquid chromatography-tandem mass spectrometry method was developed to detect ibrutinib, DHI, and zanubrutinib in human plasma. METHODS: The method involved a protein precipitation step, followed by chromatographic separation using a gradient of 10 mM ammonium acetate (containing 0.1% formic acid)-acetonitrile. Ibrutinib-d5 was used as an internal standard. Analytes were separated within 6.5 minutes. The optimized multiple reaction monitoring transitions of m/z 441.1 → 304.2, 475.2 → 304.2, 472.2 → 455.2, and 446.2 → 309.2 were selected to inspect ibrutinib, DHI, zanubrutinib, and the internal standards in positive ion mode. RESULTS: The validated curve ranges included 0.200-800, 0.500-500, and 1.00-1000 ng/mL for ibrutinib, DHI, and zanubrutinib, respectively. The precisions of the lower limit of quantification of samples were below 15.5%, the precisions of the other level samples were below 11.4%, and the accuracies were between -8.6% and 8.4%. The matrix effect and extraction recovery of all compounds ranged between 97.6%-109.0% and 93.9%-105.2%, respectively. The selectivity, accuracy, precision, matrix effect, and extraction recovery results were acceptable according to international method validation guidelines. CONCLUSIONS: A simple and rapid method was developed and validated in this study. This method was used to analyze plasma concentrations of ibrutinib and zanubrutinib in patients with mantle cell lymphoma, chronic lymphocytic leukemia/small lymphocytic lymphoma, or diffuse large B-cell lymphoma. The selected patients were aged between 44 and 74 years.


Assuntos
Adenina , Piperidinas , Pirazóis , Pirimidinas , Espectrometria de Massas em Tandem , Humanos , Piperidinas/sangue , Piperidinas/uso terapêutico , Adenina/análogos & derivados , Adenina/uso terapêutico , Adenina/sangue , Pirimidinas/sangue , Pirimidinas/uso terapêutico , Espectrometria de Massas em Tandem/métodos , Pirazóis/sangue , Pirazóis/uso terapêutico , Cromatografia Líquida/métodos , Inibidores de Proteínas Quinases/sangue , Inibidores de Proteínas Quinases/uso terapêutico , Reprodutibilidade dos Testes , Pirazinas/sangue , Pirazinas/uso terapêutico , Espectrometria de Massa com Cromatografia Líquida
15.
Ther Drug Monit ; 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39115815

RESUMO

BACKGROUND: Ripretinib, a recently developed tyrosine kinase inhibitor with switch-control abilities, can inhibit both primary and secondary activation of KIT(KIT proto-oncogene receptor tyrosine kinase) and platelet-derived growth factor receptor alpha (PDGFRA) mutants, which contribute to gastrointestinal stromal tumor progression. METHODS: In this study, a high-performance liquid chromatography-tandem mass spectrometry method to measure the concentrations of ripretinib and its active desmethyl metabolite DP-5439 in human plasma was developed and validated. Plasma samples were extracted and recovered by precipitation with acetonitrile containing the internal standard and diluted with acetonitrile before analysis. Ripretinib and DP-5439 were separated using chromatography on a Waters ACQUITY UPLC HSS T3 column (2.1 mm × 50 mm, 1.8 µm) with gradient elution using 0.1% formic acid and 5 mM ammonium formate in water as mobile phase A and acetonitrile as mobile phase B. The mobile phase was set to a flow rate of 0.5 mL/min. RESULTS: The calibration curves were linear across the following concentration range: 7.5 to 3000 ng/mL for ripretinib and 10 to 4000 ng/mL for DP-5439. The intraday and interday precisions were approximately 15% for all analytes in the quality control samples. The relative matrix effects in extracted plasma samples (90.3%-108.8% at different levels) were considered acceptable. CONCLUSIONS: This method will be a useful tool in oncology to facilitate the further clinical development of ripretinib.

16.
Nature ; 560(7718): 331-335, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30069045

RESUMO

Eukaryotic genomes are generally organized in multiple chromosomes. Here we have created a functional single-chromosome yeast from a Saccharomyces cerevisiae haploid cell containing sixteen linear chromosomes, by successive end-to-end chromosome fusions and centromere deletions. The fusion of sixteen native linear chromosomes into a single chromosome results in marked changes to the global three-dimensional structure of the chromosome due to the loss of all centromere-associated inter-chromosomal interactions, most telomere-associated inter-chromosomal interactions and 67.4% of intra-chromosomal interactions. However, the single-chromosome and wild-type yeast cells have nearly identical transcriptome and similar phenome profiles. The giant single chromosome can support cell life, although this strain shows reduced growth across environments, competitiveness, gamete production and viability. This synthetic biology study demonstrates an approach to exploration of eukaryote evolution with respect to chromosome structure and function.


Assuntos
Cromossomos Artificiais de Levedura/genética , Engenharia Genética/métodos , Aptidão Genética/genética , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Biologia Sintética/métodos , Fusão Gênica Artificial/métodos , Centrômero/genética , Evolução Molecular , Meiose , Viabilidade Microbiana/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Esporos Fúngicos/genética , Telômero/genética , Transcriptoma
17.
BMC Geriatr ; 24(1): 442, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773457

RESUMO

BACKGROUND: The purpose of this study was to evaluate the safety and efficacy of preoperative concurrent chemoradiotherapy (preCRT) for locally advanced rectal cancer in older people who were classified as "fit" by comprehensive geriatric assessment (CGA). METHODS: A single-arm, multicenter, phase II trial was designed. Patients were eligible for this study if they were aged 70 years or above and met the standards of "fit" (SIOG1) as evaluated by CGA and of the locally advanced risk category. The primary endpoint was 2-year disease-free survival (DFS). Patients were scheduled to receive preCRT (50 Gy) with raltitrexed (3 mg/m2 on days 1 and 22). RESULTS: One hundred and nine patients were evaluated by CGA, of whom eighty-six, eleven and twelve were classified into the fit, intermediate and frail category. Sixty-eight fit patients with a median age of 74 years were enrolled. Sixty-four patients (94.1%) finished radiotherapy without dose reduction. Fifty-four (79.3%) patients finished the prescribed raltitrexed therapy as planned. Serious toxicity (grade 3 or above) was observed in twenty-four patients (35.3%), and fourteen patients (20.6%) experienced non-hematological side effects. Within a median follow-up time of 36.0 months (range: 5.9-63.1 months), the 2-year overall survival (OS), cancer-specific survival (CSS) and disease-free survival (DFS) rates were 89.6% (95% CI: 82.3-96.9), 92.4% (95% CI: 85.9-98.9) and 75.6% (95% CI: 65.2-86.0), respectively. Forty-eight patients (70.6%) underwent surgery (R0 resection 95.8%, R1 resection 4.2%), the corresponding R0 resection rate among the patients with positive mesorectal fascia status was 76.6% (36/47). CONCLUSION: This phase II trial suggests that preCRT is efficient with tolerable toxicities in older rectal cancer patients who were evaluated as fit based on CGA. TRIAL REGISTRATION: The registration number on ClinicalTrials.gov was NCT02992886 (14/12/2016).


Assuntos
Quimiorradioterapia , Avaliação Geriátrica , Neoplasias Retais , Humanos , Idoso , Masculino , Feminino , Neoplasias Retais/terapia , Idoso de 80 Anos ou mais , Avaliação Geriátrica/métodos , Quimiorradioterapia/métodos , Intervalo Livre de Doença , Cuidados Pré-Operatórios/métodos , Tiofenos/administração & dosagem , Tiofenos/uso terapêutico , Equipe de Assistência ao Paciente , Quinazolinas/administração & dosagem , Quinazolinas/uso terapêutico
18.
Proc Natl Acad Sci U S A ; 118(22)2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34031249

RESUMO

SbtA is a high-affinity, sodium-dependent bicarbonate transporter found in the cyanobacterial CO2-concentrating mechanism (CCM). SbtA forms a complex with SbtB, while SbtB allosterically regulates the transport activity of SbtA by binding with adenyl nucleotides. The underlying mechanism of transport and regulation of SbtA is largely unknown. In this study, we report the three-dimensional structures of the cyanobacterial Synechocystis sp. PCC 6803 SbtA-SbtB complex in both the presence and absence of HCO3- and/or AMP at 2.7 Å and 3.2 Å resolution. An analysis of the inward-facing state of the SbtA structure reveals the HCO3-/Na+ binding site, providing evidence for the functional unit as a trimer. A structural comparison found that SbtA adopts an elevator mechanism for bicarbonate transport. A structure-based analysis revealed that the allosteric inhibition of SbtA by SbtB occurs mainly through the T-loop of SbtB, which binds to both the core domain and the scaffold domain of SbtA and locks it in an inward-facing state. T-loop conformation is stabilized by the AMP molecules binding at the SbtB trimer interfaces and may be adjusted by other adenyl nucleotides. The unique regulatory mechanism of SbtA by SbtB makes it important to study inorganic carbon uptake systems in CCM, which can be used to modify photosynthesis in crops.


Assuntos
Modelos Moleculares , Simportadores de Sódio-Bicarbonato/metabolismo , Synechocystis/metabolismo , Monofosfato de Adenosina/metabolismo , Regulação Alostérica , Simportadores de Sódio-Bicarbonato/genética , Synechocystis/genética
19.
Artigo em Inglês | MEDLINE | ID: mdl-39316330

RESUMO

PURPOSE: Endometriosis (EMS) is a relatively common gynecological disorder and almost fifty percent of women with EMS suffer from infertility. There are few treatment options for endometriosis, and often recurrences occur following surgery and medication. We aimed to identify potential diagnostic biomarkers for EMS to improve its diagnostic efficiency. METHODS: Differential analysis was utilized to choose EMS-associated abnormal miRNAs (DEMIs) and mRNAs (DEMs). ImmuneAI analysis was to evaluate the levels of immune cells in EMS. Next, the weighted gene co-expression network analysis (WGCNA) was utilized to identify the co-expression modules. Random forest and SVM analyses were used to filter the candidate biomarkers and construct the diagnostic model. qRT-PCR was used to test the expression level of the biomarkers. RESULTS: Based on the different analyses, we obtained 32 DEMIs and 516 DEMs and selected 9 abnormal immune cells whose abundance is abnormal in EMS. Next, we identified five co-expression modules associated with these abnormal immune cells. Then, 176 candidate genes which are both miRNA targets and associated with immune cells and aberrantly expressed in EMS were filtered. Subsequently, random forest analysis selected 11 genes as the diagnostic biomarkers and constructed a diagnostic model by SVM. Finally, we demonstrated that 8 of the 11 genes aberrantly expressed and with better diagnostic efficiency in EMS. CONCLUSIONS: In total, we identified 11 crucial genes regulated by 8 miRNAs that could serve as promising diagnostic biomarkers for EMS, potentially enhancing disease diagnosis with novel factors.

20.
Br J Cancer ; 128(11): 2044-2053, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36966236

RESUMO

BACKGROUND: Tumour-infiltrating lymphocytes (TILs) represent a robust biological prognostic biomarker in triple-negative breast cancer (TNBC); however, the contribution of different subsets of immune cells is unclear. We investigated the prognostic value of immune markers, including stromal TILs (sTILs), CD8+T and FOPX3+T cells, PD-1 and PD-L1 in non-metastatic TNBC. METHODS: In total, 259 patients with Stage I-III TNBC were reviewed. The density of sTILs along with the presence of total (t), stromal (s), and intratumoral (i) CD8+T cells and FOPX3+T cells were evaluated by haematoxylin and eosin and immunohistochemical staining. Immunohistochemical staining of PD-1, PD-L1 was also conducted. RESULTS: All immune markers were positively correlated with each other (P < 0.05). In the multivariate analysis, sTILs (P = 0.046), tCD8+T cells (P = 0.024), iCD8+T cells (P = 0.050) and PD-1 (P = 0.039) were identified as independent prognostic factors for disease-free survival (DFS). Further analysis showed that tCD8+T cells (P = 0.026), iCD8+T cells (P = 0.017) and PD-1 (P = 0.037) increased the prognostic value for DFS beyond that of the classic clinicopathological factors and sTILs. CONCLUSIONS: In addition to sTILs, inclusion of tCD8+T, iCD8+T cells, or PD-1 may further refine the prognostic model for non-metastatic TNBC beyond that including classical factors alone.


Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Prognóstico , Neoplasias de Mama Triplo Negativas/patologia , Antígeno B7-H1/metabolismo , Linfócitos do Interstício Tumoral , Receptor de Morte Celular Programada 1/metabolismo , Ligantes , Proteínas Reguladoras de Apoptose/metabolismo , Apoptose
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