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1.
Cell ; 182(5): 1328-1340.e13, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32814014

RESUMO

Among arthropod vectors, ticks transmit the most diverse human and animal pathogens, leading to an increasing number of new challenges worldwide. Here we sequenced and assembled high-quality genomes of six ixodid tick species and further resequenced 678 tick specimens to understand three key aspects of ticks: genetic diversity, population structure, and pathogen distribution. We explored the genetic basis common to ticks, including heme and hemoglobin digestion, iron metabolism, and reactive oxygen species, and unveiled for the first time that genetic structure and pathogen composition in different tick species are mainly shaped by ecological and geographic factors. We further identified species-specific determinants associated with different host ranges, life cycles, and distributions. The findings of this study are an invaluable resource for research and control of ticks and tick-borne diseases.


Assuntos
Variação Genética/genética , Doenças Transmitidas por Carrapatos/microbiologia , Carrapatos/genética , Animais , Linhagem Celular , Vetores de Doenças , Especificidade de Hospedeiro/genética
2.
Mol Cell ; 84(9): 1711-1726.e11, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38569554

RESUMO

N6-methyladenosine (m6A) is a crucial RNA modification that regulates diverse biological processes in human cells, but its co-transcriptional deposition and functions remain poorly understood. Here, we identified the RNA helicase DDX21 with a previously unrecognized role in directing m6A modification on nascent RNA for co-transcriptional regulation. DDX21 interacts with METTL3 for co-recruitment to chromatin through its recognition of R-loops, which can be formed co-transcriptionally as nascent transcripts hybridize onto the template DNA strand. Moreover, DDX21's helicase activity is needed for METTL3-mediated m6A deposition onto nascent RNA following recruitment. At transcription termination regions, this nexus of actions promotes XRN2-mediated termination of RNAPII transcription. Disruption of any of these steps, including the loss of DDX21, METTL3, or their enzymatic activities, leads to defective termination that can induce DNA damage. Therefore, we propose that the R-loop-DDX21-METTL3 nexus forges the missing link for co-transcriptional modification of m6A, coordinating transcription termination and genome stability.


Assuntos
Adenosina , Adenosina/análogos & derivados , RNA Helicases DEAD-box , Exorribonucleases , Instabilidade Genômica , Metiltransferases , Estruturas R-Loop , RNA Polimerase II , Terminação da Transcrição Genética , Humanos , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Metiltransferases/metabolismo , Metiltransferases/genética , Adenosina/metabolismo , Adenosina/genética , Exorribonucleases/metabolismo , Exorribonucleases/genética , RNA Polimerase II/metabolismo , RNA Polimerase II/genética , Células HEK293 , Cromatina/metabolismo , Cromatina/genética , Dano ao DNA , Células HeLa , RNA/metabolismo , RNA/genética , Transcrição Gênica , Metilação de RNA
3.
Immunity ; 50(3): 616-628.e6, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30850343

RESUMO

Humoral immunity depends on efficient activation of B cells and their subsequent differentiation into antibody-secreting cells (ASCs). The transcription factor NFκB cRel is critical for B cell proliferation, but incorporating its known regulatory interactions into a mathematical model of the ASC differentiation circuit prevented ASC generation in simulations. Indeed, experimental ectopic cRel expression blocked ASC differentiation by inhibiting the transcription factor Blimp1, and in wild-type (WT) cells cRel was dynamically repressed during ASC differentiation by Blimp1 binding the Rel locus. Including this bi-stable circuit of mutual cRel-Blimp1 antagonism into a multi-scale model revealed that dynamic repression of cRel controls the switch from B cell proliferation to ASC generation phases and hence the respective cell population dynamics. Our studies provide a mechanistic explanation of how dysregulation of this bi-stable circuit might result in pathologic B cell population phenotypes and thus offer new avenues for diagnostic stratification and treatment.


Assuntos
Linfócitos B/imunologia , Diferenciação Celular/imunologia , Proliferação de Células/fisiologia , NF-kappa B/imunologia , Animais , Células Produtoras de Anticorpos/imunologia , Linhagem Celular , Feminino , Regulação da Expressão Gênica/imunologia , Células HEK293 , Humanos , Imunidade Humoral/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL
4.
Nature ; 612(7938): 72-77, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36352229

RESUMO

Advancements in many modern technologies rely on the continuous need for materials discovery. However, the design of synthesis routes leading to new and targeted solid-state materials requires understanding of reactivity patterns1-3. Advances in synthesis science are necessary to increase efficiency and accelerate materials discovery4-10. We present a highly effective methodology for the rational discovery of materials using high-temperature solutions or fluxes having tunable solubility. This methodology facilitates product selection by projecting the free-energy landscape into real synthetic variables: temperature and flux ratio. We demonstrate the effectiveness of this technique by synthesizing compounds in the chalcogenide system of A(Ba)-Cu-Q(O) (Q = S or Se; A = Na, K or Rb) using mixed AOH/AX (A = Li, Na, K or Rb; X = Cl or I) fluxes. We present 30 unreported compounds or compositions, including more than ten unique structural types, by systematically varying the temperature and flux ratios without requiring changing the proportions of starting materials. Also, we found that the structural dimensionality of the compounds decreases with increasing reactant solubility and temperature. This methodology serves as an effective general strategy for the rational discovery of inorganic solids.

5.
Mol Cell ; 75(6): 1188-1202.e11, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31399345

RESUMO

The maternal-to-zygotic transition (MZT) is a conserved and fundamental process during which the maternal environment is converted to an environment of embryonic-driven development through dramatic reprogramming. However, how maternally supplied transcripts are dynamically regulated during MZT remains largely unknown. Herein, through genome-wide profiling of RNA 5-methylcytosine (m5C) modification in zebrafish early embryos, we found that m5C-modified maternal mRNAs display higher stability than non-m5C-modified mRNAs during MZT. We discovered that Y-box binding protein 1 (Ybx1) preferentially recognizes m5C-modified mRNAs through π-π interactions with a key residue, Trp45, in Ybx1's cold shock domain (CSD), which plays essential roles in maternal mRNA stability and early embryogenesis of zebrafish. Together with the mRNA stabilizer Pabpc1a, Ybx1 promotes the stability of its target mRNAs in an m5C-dependent manner. Our study demonstrates an unexpected mechanism of RNA m5C-regulated maternal mRNA stabilization during zebrafish MZT, highlighting the critical role of m5C mRNA modification in early development.


Assuntos
5-Metilcitosina/metabolismo , Embrião não Mamífero/embriologia , Desenvolvimento Embrionário/fisiologia , Estabilidade de RNA/fisiologia , RNA Mensageiro Estocado/metabolismo , Peixe-Zebra/embriologia , Animais , Células HeLa , Humanos , Camundongos , RNA Mensageiro Estocado/genética , Peixe-Zebra/genética
6.
Proc Natl Acad Sci U S A ; 120(11): e2215732120, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36893266

RESUMO

Immunotherapy of PD-L1/PD-1 blockage elicited impressive clinical benefits for cancer treatment. However, the relative low response and therapy resistance highlight the need to better understand the molecular regulation of PD-L1 in tumors. Here, we report that PD-L1 is a target of UFMylation. UFMylation of PD-L1 destabilizes PD-L1 by synergizing its ubiquitination. Inhibition of PD-L1 UFMylation via silencing of UFL1 or Ubiquitin-fold modifier 1 (UFM1), or the defective UFMylation of PD-L1, stabilizes the PD-L1 in multiple human and murine cancer cells, and undermines antitumor immunity in vitro and mice, respectively. Clinically, UFL1 expression was decreased in multiple cancers and lower expression of UFL1 negatively correlated with the response of anti-PD1 therapy in melanoma patients. Moreover, we identified a covalent inhibitor of UFSP2 that promoted the UFMylation activity and contributed to the combination therapy with PD-1 blockade. Our findings identified a previously unrecognized regulator of PD-L1 and highlighted UFMylation as a potential therapeutic target.


Assuntos
Antígeno B7-H1 , Melanoma , Humanos , Animais , Camundongos , Evasão Tumoral , Receptor de Morte Celular Programada 1/genética , Ubiquitinação , Cisteína Endopeptidases
7.
Lancet ; 403(10445): 2720-2731, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38824941

RESUMO

BACKGROUND: Anti-PD-1 therapy and chemotherapy is a recommended first-line treatment for recurrent or metastatic nasopharyngeal carcinoma, but the role of PD-1 blockade remains unknown in patients with locoregionally advanced nasopharyngeal carcinoma. We assessed the addition of sintilimab, a PD-1 inhibitor, to standard chemoradiotherapy in this patient population. METHODS: This multicentre, open-label, parallel-group, randomised, controlled, phase 3 trial was conducted at nine hospitals in China. Adults aged 18-65 years with newly diagnosed high-risk non-metastatic stage III-IVa locoregionally advanced nasopharyngeal carcinoma (excluding T3-4N0 and T3N1) were eligible. Patients were randomly assigned (1:1) using blocks of four to receive gemcitabine and cisplatin induction chemotherapy followed by concurrent cisplatin radiotherapy (standard therapy group) or standard therapy with 200 mg sintilimab intravenously once every 3 weeks for 12 cycles (comprising three induction, three concurrent, and six adjuvant cycles to radiotherapy; sintilimab group). The primary endpoint was event-free survival from randomisation to disease recurrence (locoregional or distant) or death from any cause in the intention-to-treat population. Secondary endpoints included adverse events. This trial is registered with ClinicalTrials.gov (NCT03700476) and is now completed; follow-up is ongoing. FINDINGS: Between Dec 21, 2018, and March 31, 2020, 425 patients were enrolled and randomly assigned to the sintilimab (n=210) or standard therapy groups (n=215). At median follow-up of 41·9 months (IQR 38·0-44·8; 389 alive at primary data cutoff [Feb 28, 2023] and 366 [94%] had at least 36 months of follow-up), event-free survival was higher in the sintilimab group compared with the standard therapy group (36-month rates 86% [95% CI 81-90] vs 76% [70-81]; stratified hazard ratio 0·59 [0·38-0·92]; p=0·019). Grade 3-4 adverse events occurred in 155 (74%) in the sintilimab group versus 140 (65%) in the standard therapy group, with the most common being stomatitis (68 [33%] vs 64 [30%]), leukopenia (54 [26%] vs 48 [22%]), and neutropenia (50 [24%] vs 46 [21%]). Two (1%) patients died in the sintilimab group (both considered to be immune-related) and one (<1%) in the standard therapy group. Grade 3-4 immune-related adverse events occurred in 20 (10%) patients in the sintilimab group. INTERPRETATION: Addition of sintilimab to chemoradiotherapy improved event-free survival, albeit with higher but manageable adverse events. Longer follow-up is necessary to determine whether this regimen can be considered as the standard of care for patients with high-risk locoregionally advanced nasopharyngeal carcinoma. FUNDING: National Natural Science Foundation of China, Key-Area Research and Development Program of Guangdong Province, Natural Science Foundation of Guangdong Province, Overseas Expertise Introduction Project for Discipline Innovation, Guangzhou Municipal Health Commission, and Cancer Innovative Research Program of Sun Yat-sen University Cancer Center. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Assuntos
Anticorpos Monoclonais Humanizados , Quimiorradioterapia , Quimioterapia de Indução , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Carcinoma Nasofaríngeo/terapia , Carcinoma Nasofaríngeo/tratamento farmacológico , Adulto , China/epidemiologia , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/terapia , Quimiorradioterapia/métodos , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/administração & dosagem , Idoso , Cisplatino/uso terapêutico , Cisplatino/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Gencitabina , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Desoxicitidina/administração & dosagem , Adulto Jovem , Adolescente , Intervalo Livre de Progressão
8.
Circ Res ; 133(3): 200-219, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37350264

RESUMO

BACKGROUND: The mTOR (mechanistic target of rapamycin) pathway is a complex signaling cascade that regulates cellular growth, proliferation, metabolism, and survival. Although activation of mTOR signaling has been linked to atherosclerosis, its direct role in lesion progression and in plaque macrophages remains poorly understood. We previously demonstrated that mTORC1 (mTOR complex 1) activation promotes atherogenesis through inhibition of autophagy and increased apoptosis in macrophages. METHODS: Using macrophage-specific Rictor- and mTOR-deficient mice, we now dissect the distinct functions of mTORC2 pathways in atherogenesis. RESULTS: In contrast to the atheroprotective effect seen with blockade of macrophage mTORC1, macrophage-specific mTORC2-deficient mice exhibit an atherogenic phenotype, with larger, more complex lesions and increased cell death. In cultured macrophages, we show that mTORC2 signaling inhibits the FoxO1 (forkhead box protein O1) transcription factor, leading to suppression of proinflammatory pathways, especially the inflammasome/IL (interleukin)-1ß response, a key mediator of vascular inflammation and atherosclerosis. In addition, administration of FoxO1 inhibitors efficiently rescued the proinflammatory response caused by mTORC2 deficiency both in vitro and in vivo. Interestingly, collective deletion of macrophage mTOR, which ablates mTORC1- and mTORC2-dependent pathways, leads to minimal change in plaque size or complexity, reflecting the balanced yet opposing roles of these signaling arms. CONCLUSIONS: Our data provide the first mechanistic details of macrophage mTOR signaling in atherosclerosis and suggest that therapeutic measures aimed at modulating mTOR need to account for its dichotomous functions.


Assuntos
Aterosclerose , Serina-Treonina Quinases TOR , Camundongos , Animais , Alvo Mecanístico do Complexo 2 de Rapamicina , Serina-Treonina Quinases TOR/metabolismo , Macrófagos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Fatores de Transcrição/metabolismo , Aterosclerose/genética , Aterosclerose/metabolismo
9.
Proc Natl Acad Sci U S A ; 119(30): e2202682119, 2022 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-35858430

RESUMO

Heterogeneous peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) have shown a great potential for pollutant degradation, but their feasibility for large-scale water treatment application has not been demonstrated. Herein, we develop a facile coprecipitation method for the scalable production (∼10 kg) of the Cu-Fe-Mn spinel oxide (CuFeMnO). Such a catalyst has rich oxygen vacancies and symmetry-breaking sites, which endorse it with a superior PMS-catalytic capacity. We find that the working reactive species and their contributions are highly dependent on the properties of target organic pollutants. For the organics with electron-donating group (e.g., -OH), high-valent metal species are mainly responsible for the pollutant degradation, whereas for the organics with electron-withdrawing group (e.g., -COOH and -NO2), hydroxyl radical (•OH) as the secondary oxidant also plays an important role. We demonstrate that the CuFeMnO-PMS system is able to achieve efficient and stable removal of the pollutants in the secondary effluent from a municipal wastewater plant at both bench and pilot scales. Moreover, we explore the application prospect of this PMS-based AOP process for large-scale wastewater treatment. This work describes an opportunity to scalably prepare robust spinel oxide catalysts for water purification and is beneficial to the practical applications of the heterogeneous PMS-AOPs.


Assuntos
Óxido de Alumínio , Óxido de Magnésio , Peróxidos , Poluentes da Água , Purificação da Água , Óxido de Alumínio/química , Catálise , Óxido de Magnésio/química , Peróxidos/química , Poluentes da Água/química , Purificação da Água/métodos
10.
Eur Heart J ; 45(17): 1512-1520, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38568209

RESUMO

BACKGROUND AND AIMS: Studies on the impact of syphilis on the cardiovascular system in large populations are limited. This study investigated the effects of syphilis on cardiovascular outcomes. METHODS: Medical records from 2010 to 2015 were retrieved from the Taiwan National Health Insurance Research Database, linked to the Notifiable Infectious Diseases database from the Taiwan Centers for Disease Control. Patients with syphilis were identified, excluding those with missing information, under 20 years of age, or with a history of human immunodeficiency virus infection, acute myocardial infarction, heart failure, aortic regurgitation, replacement of the aortic valve, aneurysm and/or dissection of the aorta, atrial fibrillation, ischaemic stroke, haemorrhagic stroke, and venous thromboembolism. Primary outcomes included new-onset acute myocardial infarction, heart failure, aortic regurgitation, aneurysm and dissection of the aorta, atrial fibrillation, ischaemic stroke, haemorrhagic stroke, venous thromboembolism, cardiovascular death, and all-cause mortality. RESULTS: A total of 28 796 patients with syphilis were identified from 2010 to 2015. After exclusions and frequency matching, 20 601 syphilis patients and 20 601 non-syphilis patients were analysed. The relative rate (RR) was utilized in the analysis, as the competing risk of death was not considered. Compared with patients without syphilis, patients with syphilis had increased risks of acute myocardial infarction (RR 38%, 95% confidence interval [CI] 1.19-1.60, P < .001), heart failure (RR 88%, 95% CI 1.64-2.14, P < .001), aortic regurgitation (RR 81%, 95% CI 1.18-2.75, P = .006), atrial fibrillation (RR 45%, 95% CI 1.20-1.76, P < .001), ischaemic stroke (RR 68%, 95% CI 1.52-1.87, P < .001), haemorrhagic stroke (RR 114%, 95% CI 1.74-2.64, P < .001), venous thromboembolism (RR 67%, 95% CI 1.23-2.26, P = .001), cardiovascular death (RR 155%, 95% CI 2.11-3.08, P < .001), and all-cause death (RR 196%, 95% CI 2.74-3.19, P < .001) but not for aneurysm and dissection of the aorta. CONCLUSIONS: This study demonstrates that patients with syphilis have a higher risk of cardiovascular events and all-cause mortality compared with those without syphilis.


Assuntos
Sistema de Registros , Sífilis , Humanos , Taiwan/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Sífilis/epidemiologia , Sífilis/complicações , Adulto , Infarto do Miocárdio/epidemiologia , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/epidemiologia , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/complicações , Fatores de Risco de Doenças Cardíacas , Estudos Retrospectivos
11.
J Cell Mol Med ; 28(2): e18071, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38044583

RESUMO

Oral squamous cell carcinoma (OSCC), which accounts for 90% of all oral cancers, has become a public health crisis worldwide. despite advances in therapeutic interventions, the prognosis remains poor for advanced-stage OSCC. In this study, we investigate the anticancer activity and the mode of action of hellebrigenin in human OSCC. The findings demonstrated that hellebrigenin exerted cytotoxic effects in OSCC cells through cell cycle arrest at the G2/M phase and downregulation of cell cycle-related proteins (cyclins A2, B1 and D3, Cdc2, CDK4 and CDK6). Moreover, hellebrigenin caused activation of PARP and caspase 3, 8 and 9, followed by downregulation of antiapoptotic proteins (Bcl-2 and Bcl-xL) and upregulation of pro-apoptotic proteins (Bax and Bak). The hellebrigenin treatment also increased Fas, DR5, DcR2 and DcR3 expressions in oral cancer cells, indicating the compound causes oral cancer cell apoptosis through both intrinsic and extrinsic pathways. Regarding upstream signalling, hellebrigenin was found to reduce the phosphorylation of ERK, p38, and JNK, indicating that hellebrigenin triggers caspase-mediated apoptosis by downregulating MAPK signalling pathway. Finally, the human apoptosis array findings revealed that hellebrigenin specifically suppressed the expression of XIAP to execute its pro-apoptotic activities. Taken together, the study suggests that hellebrigenin can act as a potent anticancer compound in human OSCC.


Assuntos
Bufanolídeos , Carcinoma de Células Escamosas , Neoplasias Bucais , Humanos , Neoplasias Bucais/tratamento farmacológico , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Transdução de Sinais , Apoptose/fisiologia , Proteínas de Ciclo Celular/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
12.
Eur J Neurosci ; 59(3): 446-456, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38123158

RESUMO

The anterior cingulate cortex (ACC) and visual cortex are integral components of the neurophysiological mechanisms underlying migraine, yet the impact of altered connectivity patterns between these regions on migraine treatment remains unknown. To elucidate this issue, we investigated the abnormal causal connectivity between the ACC and visual cortex in patients with migraine without aura (MwoA), based on the resting-state functional magnetic resonance imaging data, and its predictive ability for the efficacy of nonsteroidal anti-inflammatory drugs (NSAIDs). The results revealed increased causal connectivity from the bilateral ACC to the lingual gyrus (LG) and decreased connectivity in the opposite direction in nonresponders compared with the responders. Moreover, compared with the healthy controls, nonresponders exhibited heightened causal connectivity from the ACC to the LG, right inferior occipital gyrus (IOG) and left superior occipital gyrus, while connectivity patterns from the LG and right IOG to the ACC were diminished. Based on the observed abnormal connectivity patterns, the support vector machine (SVM) models showed that the area under the receiver operator characteristic curves for the ACC to LG, LG to ACC and bidirectional models were 0.857, 0.898, and 0.939, respectively. These findings indicate that neuroimaging markers of abnormal causal connectivity in the ACC-visual cortex circuit may facilitate clinical decision-making regarding NSAIDs administration for migraine management.


Assuntos
Enxaqueca sem Aura , Córtex Visual , Humanos , Giro do Cíngulo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Enxaqueca sem Aura/patologia , Córtex Visual/diagnóstico por imagem , Anti-Inflamatórios não Esteroides/farmacologia , Anti-Inflamatórios não Esteroides/uso terapêutico , Anti-Inflamatórios , Encéfalo
13.
Am J Transplant ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38642712

RESUMO

Immune checkpoint inhibitors (ICIs) as a downstaging or bridging therapy for liver transplantation (LT) in hepatocellular carcinoma patients are rapidly increasing. However, the evidence about the feasibility and safety of pre-LT ICI therapy is limited and controversial. To this end, a multicenter, retrospective cohort study was conducted in 11 Chinese centers. The results showed that 83 recipients received pre-LT ICI therapy during the study period. The median post-LT follow-up was 8.1 (interquartile range 3.3-14.6) months. During the short follow-up, 23 (27.7%) recipients developed allograft rejection, and 7 of them (30.4%) were diagnosed by liver biopsy. Multivariate logistics regression analysis showed that the time interval between the last administration of ICI therapy and LT (TLAT) ≥ 30 days was an independent protective factor for allograft rejection (odds ratio = 0.096, 95% confidence interval 0.026-0.357; P < .001). Multivariate Cox analysis showed that allograft rejection was an independent risk factor for overall survival (hazard ratio = 9.960, 95% confidence interval 1.006-98.610; P = .043). We conclude that patients who receive a pre-LT ICI therapy with a TLAT shorter than 30 days have a much higher risk of allograft rejection than those with a TLAT longer than 30 days. The presence of rejection episodes might be associated with higher post-LT mortality.

14.
Mol Med ; 30(1): 10, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38216878

RESUMO

BACKGROUND: Increased oxidative stress contributes to enhanced osteoclastogenesis and age-related bone loss. Melatonin (MT) is an endogenous antioxidant and declines with aging. However, it was unclear whether the decline of MT was involved in the enhanced osteoclastogenesis during the aging process. METHODS: The plasma level of MT, oxidative stress status, bone mass, the number of bone marrow-derived monocytes (BMMs) and its osteoclastogenesis were analyzed in young (3-month old) and old (18-month old) mice (n = 6 per group). In vitro, BMMs isolated from aged mice were treated with or without MT, followed by detecting the change of osteoclastogenesis and intracellular reactive oxygen species (ROS) level. Furthermore, old mice were treated with MT for 2 months to investigate the therapeutic effect. RESULTS: The plasma level of MT was markedly lower in aged mice compared with young mice. Age-related decline in MT was accompanied by enhanced oxidative stress, osteoclastogenic potential and bone loss. MT intervention significantly suppressed the receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis, decreased intracellular ROS and enhanced antioxidant capacity of BMMs from aged mice. MT supplementation significantly attenuated oxidative stress, osteoclastogenesis, bone loss and deterioration of bone microstructure in aged mice. CONCLUSIONS: These results suggest that age-related decline of MT enhanced osteoclastogenesis via disruption of redox homeostasis. MT may serve as a key regulator in osteoclastogenesis and bone homeostasis, thereby highlighting its potential as a preventive agent for age-related bone loss.


Assuntos
Melatonina , Osteoporose , Animais , Camundongos , Osteogênese , Osteoclastos/metabolismo , Melatonina/farmacologia , Espécies Reativas de Oxigênio , Antioxidantes/farmacologia , Oxirredução , Homeostase , Diferenciação Celular , NF-kappa B/metabolismo
15.
Small ; 20(4): e2304119, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37759420

RESUMO

Although antibiotic is still the main choice for antibacteria both in hospital and community, phototherapy has become a possibly one of the alternative approaches in the treatment of microbe-associated infections nowadays because of its considerable potential in effective eradication of pathogenic bacteria. However, overwhelming reactive oxygen species (ROS) generated from phototherapy inevitably provoke an inflammatory response, complicating the healing process. To address this outstanding issue, a MXene-decorated nanofibrious is devised that not only yield localized heat but also elevate ROS levels under near-infrared laser exposure ascribed to the synergistic photothermal/photodynamic effect, for potent bacterial inactivation. After being further loaded with aspirin, the nanofibrous membranes exhibit benign cytocompatibility, boosting cell growth and suppressing the (nuclear factor kappa-B ( NF-κB) signaling pathways through RNA sequencing analysis, indicating an excellent anti-inflammatory effect. Interestingly, in vivo investigations also corroborate that the nanofibrous membranes accelerate infectious cutaneous regeneration by efficiently killing pathogenic bacteria, promoting collagen deposition, boosting angiogenesis, and dampening inflammatory reaction via steering NF-κB pathway. As envisaged, this work furnishes a decorated nanofibrous membrane with programmed antibacterial and anti-inflammatory effects for remedy of refractory bacteria-invaded wound regeneration.


Assuntos
NF-kappa B , Nanofibras , Nitritos , Elementos de Transição , NF-kappa B/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Cicatrização , Anti-Inflamatórios/farmacologia , Antibacterianos/farmacologia
16.
Small ; 20(15): e2308278, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009756

RESUMO

Designing cost-efffective electrocatalysts for the oxygen evolution reaction (OER) holds significant importance in the progression of clean energy generation and efficient energy storage technologies, such as water splitting and rechargeable metal-air batteries. In this work, an OER electrocatalyst is developed using Ni and Fe precursors in combination with different proportions of graphene oxide. The catalyst synthesis involved a rapid reduction process, facilitated by adding sodium borohydride, which successfully formed NiFe nanoparticle nests on graphene support (NiFe NNG). The incorporation of graphene support enhances the catalytic activity, electron transferability, and electrical conductivity of the NiFe-based catalyst. The NiFe NNG catalyst exhibits outstanding performance, characterized by a low overpotential of 292.3 mV and a Tafel slope of 48 mV dec-1, achieved at a current density of 10 mA cm- 2. Moreover, the catalyst exhibits remarkable stability over extended durations. The OER performance of NiFe NNG is on par with that of commercial IrO2 in alkaline media. Such superb OER catalytic performance can be attributed to the synergistic effect between the NiFe nanoparticle nests and graphene, which arises from their large surface area and outstanding intrinsic catalytic activity. The excellent electrochemical properties of NiFe NNG hold great promise for further applications in energy storage and conversion devices.

17.
Small ; 20(5): e2304636, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37789503

RESUMO

The development of electrocatalysts that are not reliant on iridium for efficient acid-oxygen evolution is a critical step towards the proton exchange membrane water electrolysis (PEMWE) and green hydrogen industry. Ruthenium-based electrocatalysts have garnered widespread attention due to their remarkable catalytic activity and lower commercial price. However, the challenge lies in balancing the seesaw relationship between activity and stability of these electrocatalysts during the acid-oxygen evolution reaction (OER). This review delves into the progress made in Ru-based electrocatalysts with regards to acid OER and PEMWE applications. It highlights the significance of customizing the acidic OER mechanism of Ru-based electrocatalysts through the coordination of adsorption evolution mechanism (AEM) and lattice oxygen oxidation mechanism (LOM) to attain the ideal activity and stability relationship. The promising tradeoffs between the activity and stability of different Ru-based electrocatalysts, including Ru metals and alloys, Ru single-atomic materials, Ru oxides, and derived complexes, and Ru-based heterojunctions, as well as their applicability to PEMWE systems, are discussed in detail. Furthermore, this paper offers insights on in situ control of Ru active sites, dynamic catalytic mechanism, and commercial application of PEMWE. Based on three-way relationship between cost, activity, and stability, the perspectives and development are provided.

18.
Mol Phylogenet Evol ; 190: 107956, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37898296

RESUMO

Phylogenomic conflicts are widespread among genomic data, with most previous studies primarily focusing on nuclear datasets instead of organellar genomes. In this study, we investigate phylogenetic conflict analyses within and between plastid and mitochondrial genomes using Potentilla as a case study. We generated three plastid datasets (coding, noncoding, and all-region) and one mitochondrial dataset (coding regions) to infer phylogenies based on concatenated and multispecies coalescent (MSC) methods. Conflict analyses were then performed using PhyParts and Quartet Sampling (QS). Both plastid and mitochondrial genomes divided the Potentilla into eight highly supported clades, two of which were newly identified in this study. While most organellar loci were uninformative for the majority of nodes (bootstrap value < 70%), PhyParts and QS detected conflicting signals within the two organellar genomes. Regression analyses revealed that conflict signals mainly occurred among shorter loci, whereas longer loci tended to be more concordant with the species tree. In addition, two significant disagreements between the two organellar genomes were detected, likely attributed to hybridization and/or incomplete lineage sorting. Our results demonstrate that mitochondrial genes can fully resolve the phylogenetic relationships among eight major clades of Potentilla and are not always linked with plastome in evolutionary history. Stochastic inferences appear to be the primary source of observed conflicts among the gene trees. We recommend that the loci with short sequence length or containing limited informative sites should be used cautiously in MSC analysis, and suggest the joint application of concatenated and MSC methods for phylogenetic inference using organellar genomes.


Assuntos
Genoma Mitocondrial , Genomas de Plastídeos , Potentilla , Rosaceae , Filogenia , Potentilla/genética , Rosaceae/genética , Plastídeos/genética
19.
Microb Pathog ; 192: 106684, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38759934

RESUMO

BACKGROUND: Gut bacteria have an important influence on colorectal cancer (CRC). The differences of gut bacteria between genders have been the hot spots. OBJECTIVE: To analyze the relationship between gut bacteria and gender differences in patients with CRC. METHODS: A total of 212 patients with CRC and 212 healthy volunteers were recruited. The subjects' fecal samples were obtained, and the fecal microorganisms were analyzed by the third-generation sequencing PacBio. The composition of gut bacteria was analyzed. Linear discriminant analysis Effect Size (LEfSe) was used to analyze the differences in gut bacteria. Pearson coefficient was used to calculate the correlation between differential bacteria. CRC risk prediction models were used to rank the importance of effective differential bacteria. RESULTS: Escherichia flexneri and Phocaeicola vulgatus were the most frequent bacteria in both male and female CRC patients. Bacteroides, Verrucomicrobia and Akkermansiaceae were highly enriched in male CRC group, while Bacteroidetes, Phocaeicola and Tissierellales were highly enriched in female CRC group. Peptostreptococcus anaerobius and Phocaeicola vulgatus were important CRC related bacteria in males and females, respectively. Peptostreptococcus anaerobius was the most important characteristic bacterium of males (AUC = 0.951), and the sensitivity and specificity of the discovery set were 78.74 % and 93.98 %, respectively. Blautia stercoris was the most important characteristic bacterium of females (AUC = 0.966), and the sensitivity and specificity of the discovery set were 90.63 % and 90.63 %, respectively. CONCLUSION: Gut bacteria varied in different genders. Therefore, gender should be considered when gut bacteria are applied in the diagnose and prevention of CRC.


Assuntos
Bactérias , Neoplasias Colorretais , Fezes , Microbioma Gastrointestinal , Humanos , Neoplasias Colorretais/microbiologia , Masculino , Feminino , Microbioma Gastrointestinal/genética , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Fezes/microbiologia , Pessoa de Meia-Idade , Fatores Sexuais , Idoso , Sequenciamento de Nucleotídeos em Larga Escala , Adulto , RNA Ribossômico 16S/genética
20.
Phys Rev Lett ; 132(15): 156701, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682975

RESUMO

A new perovskite KOsO_{3} has been stabilized under high-pressure and high-temperature conditions. It is cubic at 500 K (Pm-3m) and undergoes subsequent phase transitions to tetragonal at 320 K (P4/mmm) and rhombohedral (R-3m) at 230 K as shown from refining synchrotron x-ray powder diffraction (SXRD) data. The larger orbital overlap integral and the extended wave function of 5d electrons in the perovskite KOsO_{3} allow to explore physics from the regime where Mott and Hund's rule couplings dominate to the state where the multiple interactions are on equal footing. We demonstrate an exotic magnetic ordering phase found by neutron powder diffraction along with physical properties via a suite of measurements including magnetic and transport properties, differential scanning calorimetry, and specific heat, which provide comprehensive information for a system at the crossover from localized to itinerant electronic behavior.

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