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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.
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
6.
Nano Lett ; 2024 Jun 18.
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.

7.
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.

8.
Ann Hematol ; 2024 Apr 12.
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.

9.
Ther Drug Monit ; 2024 Mar 21.
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.

10.
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
11.
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
12.
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
13.
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
14.
Nat Immunol ; 12(10): 959-65, 2011 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-21892174

RESUMO

The recognition of pathogenic DNA is important to the initiation of antiviral responses. Here we report the identification of DDX41, a member of the DEXDc family of helicases, as an intracellular DNA sensor in myeloid dendritic cells (mDCs). Knockdown of DDX41 expression by short hairpin RNA blocked the ability of mDCs to mount type I interferon and cytokine responses to DNA and DNA viruses. Overexpression of both DDX41 and the membrane-associated adaptor STING together had a synergistic effect in promoting Ifnb promoter activity. DDX41 bound both DNA and STING and localized together with STING in the cytosol. Knockdown of DDX41 expression blocked activation of the mitogen-activated protein kinase TBK1 and the transcription factors NF-κB and IRF3 by B-form DNA. Our results suggest that DDX41 is an additional DNA sensor that depends on STING to sense pathogenic DNA.


Assuntos
RNA Helicases DEAD-box/fisiologia , DNA Helicases/fisiologia , DNA/metabolismo , Células Dendríticas/fisiologia , Proteínas de Membrana/fisiologia , Animais , Células da Medula Óssea/metabolismo , Células Cultivadas , Humanos , Interferons/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Monócitos/virologia , Estrutura Terciária de Proteína , Transdução de Sinais
15.
Plant Physiol ; 190(3): 1883-1895, 2022 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-35947692

RESUMO

Efficient solar energy conversion is ensured by the organization, physical association, and physiological coordination of various protein complexes in photosynthetic membranes. Here, we visualize the native architecture and interactions of photosynthetic complexes within the thylakoid membranes from a fast-growing cyanobacterium Synechococcus elongatus UTEX 2973 (Syn2973) using high-resolution atomic force microscopy. In the Syn2973 thylakoid membranes, both photosystem I (PSI)-enriched domains and crystalline photosystem II (PSII) dimer arrays were observed, providing favorable membrane environments for photosynthetic electron transport. The high light (HL)-adapted thylakoid membranes accommodated a large amount of PSI complexes, without the incorporation of iron-stress-induced protein A (IsiA) assemblies and formation of IsiA-PSI supercomplexes. In the iron deficiency (Fe-)-treated thylakoid membranes, in contrast, IsiA proteins densely associated with PSI, forming the IsiA-PSI supercomplexes with varying assembly structures. Moreover, type-I NADH dehydrogenase-like complexes (NDH-1) were upregulated under the HL and Fe- conditions and established close association with PSI complexes to facilitate cyclic electron transport. Our study provides insight into the structural heterogeneity and plasticity of the photosynthetic apparatus in the context of their native membranes in Syn2973 under environmental stress. Advanced understanding of the photosynthetic membrane organization and adaptation will provide a framework for uncovering the molecular mechanisms of efficient light harvesting and energy conversion.


Assuntos
Complexos de Proteínas Captadores de Luz , Complexo de Proteína do Fotossistema I , Complexos de Proteínas Captadores de Luz/metabolismo , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Tilacoides/metabolismo , Aclimatação
16.
BMC Cancer ; 23(1): 486, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37254046

RESUMO

BACKGROUND: Thermal therapy induces an immune response in patients with hepatocellular carcinoma (HCC), but the dynamic characteristics of the natural killer (NK) cell immune response post-thermal ablation remain unclear. We conducted a prospective longitudinal cohort study to observe the dynamic changes of phenotype and function of NK cells in peripheral blood before and after thermal ablation of hepatitis B-associated HCC and their correlation with tumor recurrence. METHODS: Fifty-six patients clinically and pathologically confirmed with hepatitis B-associated HCC were selected for thermal ablation. Peripheral blood was collected on day 0, day 7, and month 1. NK cell subsets, receptors, and killing function were detected by flow cytometry, and the LDH levels were examined. Overall recurrence and associated variables were estimated using Kaplan-Meier, log-rank, and Cox proportional-hazards analyses. RESULTS: The frequency of CD3-CD56+ cells was increased on day 7 (P < 0.01) without significant differences between D0 and M1. NKG2D, NKp44, NKp30, CD159a, and CD158a expression was increased on M1 (all P < 0.05). The granzyme B and IFN-γ expression in NK cells were higher on M1 vs. D0 (P < 0.05). On day 7, the NK cell lysis activity of the target K562 cells was increased (P < 0.01) but decreased on M1 (P < 0.05). Survival analysis showed that CD158a expression and IFN-γ and perforin release on day 0 were associated with the risk of HCC recurrence. Cox regression analysis showed that the expression changes in CD56, NKp46, granzyme B, and perforin (D7-D0) induced by thermal ablation were associated with recurrence-free survival (RFS) of patients with HCC. CONCLUSION: Thermal ablation increased the frequency and function of CD3-CD56+ NK cells in the peripheral blood of patients with HCC. These cells tended to be more differentiated and activated. Notably, expression levels of NK cell receptors NKp46, perforin, and granzyme B were associated with RFS.


Assuntos
Carcinoma Hepatocelular , Hepatite B , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Carcinoma Hepatocelular/metabolismo , Granzimas/metabolismo , Perforina/metabolismo , Estudos Prospectivos , Estudos Longitudinais , Recidiva Local de Neoplasia/metabolismo , Neoplasias Hepáticas/cirurgia , Neoplasias Hepáticas/metabolismo , Células Matadoras Naturais , Fenótipo , Hepatite B/complicações , Hepatite B/metabolismo
17.
BMC Cancer ; 23(1): 88, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36698118

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) performs well in the locoregional assessment of extranodal nasal-type NK/T-cell lymphoma (ENKTCL). It's important to assess the value of multi-modal MRI-based radiomics for estimating overall survival (OS) in patients with ENKTCL. METHODS: Patients with ENKTCL in a prospectively cohort were systemically reviewed and all the pretreatment MRI were acquisitioned. An unsupervised spectral clustering method was used to identify risk groups of patients and radiomic features. A nomogram-revised risk index (NRI) plus MRI radiomics signature (NRI-M) was developed, and compared with the NRI. RESULTS: The 2 distinct type I and II groups of the MRI radiomics signatures were identified. The 5-year OS rates between the type I and type II groups were 87.2% versus 67.3% (P = 0.002) in all patients, and 88.8% versus 69.2% (P = 0.003) in early-stage patients. The discrimination and calibration of the NRI-M for OS prediction demonstrated a better performance than that of either MRI radiomics or NRI, with a mean area under curve (AUC) of 0.748 and 0.717 for predicting the 5-year OS in all-stages and early-stage patients. CONCLUSIONS: The NRI-M model has good performance for predicting the prognosis of ENKTCL and may help design clinical trials and improve clinical decision making.


Assuntos
Linfoma Extranodal de Células T-NK , Linfoma de Células T , Humanos , Prognóstico , Imageamento por Ressonância Magnética/métodos , Nomogramas , Medição de Risco , Estudos Retrospectivos , Linfoma Extranodal de Células T-NK/diagnóstico por imagem , Linfoma Extranodal de Células T-NK/patologia
18.
Hematol Oncol ; 41(5): 922-932, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37496287

RESUMO

Donor lymphocyte infusion (DLI) cures relapsed hematologic malignancies after allogeneic hematopoietic stem cell transplantation through the graft-versus-tumor (GVT) effect. Although the important role of magnesium in enhancing immunity has been mentioned in studies, limited clinical data have explored how magnesium affects the efficacy of DLI. Besides, although laboratory data demonstrate that magnesium can enhance CD8+ T cells effector function, whether magnesium regulates the tumor killing effect of peripheral blood mononuclear cells (PBMCs) remains to be explored. Here, for the retrospective study, we collected clinical data of relapsed patients receiving DLI and explored the relationship between different serum magnesium levels and patient outcomes. For in vitro studies, we investigated the effect of magnesium on the cytotoxicity of DLI cells which were PBMCs and preliminarily explored the mechanism. Eighty-one patients were enrolled in this study. It was found that the high post-DLI magnesium level was significantly associated with a higher incidence of complete remission (CR) or partial remission (CR/PR) and a higher possibility of survival. The magnesium level after DLI was an independent risk factor of overall survival. In vitro studies proved that increased magnesium enhanced the cytotoxic function of PBMCs on hematologic malignancies. Besides, magnesium modulated LFA-1 headpiece opening. When blocking the integrin-ligand interaction between LFA-1 and ICAM-1, the regulation effect of magnesium on PBMCs was weakened. Therefore, it was possible that magnesium regulated PBMCs effector function by stimulating LFA-1. These results show that serum magnesium levels affect immunological responses mediated by donor lymphocytes in hematologic malignancies.


Assuntos
Doença Enxerto-Hospedeiro , Neoplasias Hematológicas , Transplante de Células-Tronco Hematopoéticas , Humanos , Magnésio , Linfócitos T CD8-Positivos , Leucócitos Mononucleares , Estudos Retrospectivos , Antígeno-1 Associado à Função Linfocitária , Doença Enxerto-Hospedeiro/etiologia , Recidiva Local de Neoplasia , Transplante de Células-Tronco Hematopoéticas/métodos , Transfusão de Linfócitos/métodos
19.
Ther Drug Monit ; 45(5): 599-605, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37199420

RESUMO

BACKGROUND: Orelabrutinib is a second-generation Bruton tyrosine kinase inhibitor that improves the management of B-cell malignancies. The objective of this study was to develop and validate an LC-MS/MS method for quantifying orelabrutinib in human plasma. METHODS: Plasma samples were processed using acetonitrile to precipitate proteins. Ibrutinib-d5 was used as the internal standard. The mobile phase comprised 10 mM ammonium formate containing 0.1% formic acid and acetonitrile (62:38, vol/vol). The multiple reaction monitoring transitions at m / z = 428.1 → 411.2 and 446.2 → 309.2 were selected for orelabrutinib and ibrutinib-d5, respectively, after ionization in the positive mode. RESULTS: Total runtime was 4.5 minutes. The validated curve ranges were 1.00-500 ng/mL. This method exhibited acceptable selectivity, dilution integrity, matrix effects, and recovery. Interrun and intrarun accuracy ranged from -3.4% to 6.5%, and interrun and intrarun precision was between 2.8% and 12.8%. Stability was studied under different conditions. The incurred sample reanalysis demonstrated good reproducibility. CONCLUSIONS: The LC-MS/MS method provided a simple, specific, and rapid quantification of orelabrutinib in the plasma of patients with mantle cell lymphoma or chronic lymphocytic leukemia/small lymphocytic lymphoma. The results indicated that orelabrutinib exhibits large variability between individuals and should be prudently used in combination with CYP3A4 inhibitors.


Assuntos
Plasma , Espectrometria de Massas em Tandem , Humanos , Adulto , Cromatografia Líquida/métodos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem/métodos , Inibidores de Proteínas Quinases , Cromatografia Líquida de Alta Pressão/métodos
20.
J Pathol ; 258(4): 395-407, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36098222

RESUMO

Multifocal esophageal squamous cell carcinomas (ESCCs) can be diagnosed as of multicentric origin (MO) or intramural metastasis (IMM). We aimed here to accurately discriminate MO from IMM and explore the tumor immune microenvironment of multifocal ESCCs. Multifocal ESCCs were identified in 333 ESCC patients, and in 145 patients discrimination between MO and IMM was not possible by histopathological examination. Of the 145 patients, tissues of 14 were analyzed by whole-exome sequencing (WES) of 71 different tumor regions, and MO, IMM, and MO/IMM mixed groups were identified in three, ten, and one cases, respectively, based on the similarity of genomic architecture between or among different tumors from one patient. Further phylogenetic analyses revealed complex clonal evolution patterns in IMM cases, and tumor cells disseminated from the primary tumors to IMM tumors were independent of lymph node metastasis. The NanoString-based assay showed that immune cell infiltrates were significantly enriched, and that the immune and proliferation pathways were more activated, in large tumors than in small ones in MO but not IMM cases. Similarly, PD-L1 expression and the density of paratumoral CD8+ T cells were higher in large tumors than in small tumors in MO. Taken together, through analysis of the genomic and immune landscapes, our study has comprehensively characterized the heterogeneity and clonal relationship of multifocal ESCCs, which may be helpful in distinguishing MO from IMM, and for interpreting the immunotherapy responses for multifocal ESCC patients. © 2022 The Pathological Society of Great Britain and Ireland.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Carcinoma de Células Escamosas do Esôfago/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Filogenia , Linfócitos T CD8-Positivos/patologia , Metástase Linfática , Microambiente Tumoral
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