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Singlet oxygen (1O2) is important in the environmental remediation field, however, its efficient production has been severely hindered by the ultrafast self-quenching of the as-generated radical precursors in the Fenton-like reactions. Herein, we elaborately designed lamellar anthraquinone-based covalent organic frameworks (DAQ-COF) with sequential localization of the active sites (CâO) at molecular levels for visible-light-assisted peroxymonosulfate (PMS) activation. Theoretical and experimental results revealed that the radical precursors (SO5·-) were formed in the nearby layers with the migration distance less than 0.34 nm, via PMS donating electrons to the photogenerated holes. This interlayer synergistic effect eventually led to ultraefficient 1O2 production (14.8 µM s-1), which is 12 times that of the highest reported catalyst. As an outcome, DAQ-COF enabled the complete degradation of bisphenol A in 5 min with PMS under natural sunlight irradiation. This interlayer synergistic concept represents an innovative and effective strategy to increase the utilization efficiency of ultrashort-lived radical precursors, providing inspirations for subtle structural construction of Fenton-like catalysts.
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CD8+ T cell immunity, mediated by human leukocyte antigen (HLA) and T cell receptor (TCR), plays a critical role in conferring immune memory and protection against viral pathogens. The emergence of SARS-CoV-2 variants poses a serious challenge to the efficacy of current vaccines. Whereas numerous SARS-CoV-2 mutations associated with immune escape from CD8+ T cells have been documented, the molecular effects of most mutations on epitope-specific TCR recognition remain largely unexplored. Here, we studied an HLA-A24-restricted NYN epitope (Spike448-456) that elicits broad CD8+ T cell responses in COVID-19 patients characterized by a common TCR repertoire. Four natural mutations, N450K, L452Q, L452R, and Y453F, arose within the NYN epitope and have been transmitted in certain viral lineages. Our findings indicate that these mutations have minimal impact on the epitope's presentation by cell surface HLA, yet they diminish the affinities of their respective peptide-HLA complexes (pHLAs) for NYN peptide-specific TCRs, particularly L452R and Y453F. Furthermore, we determined the crystal structure of HLA-A24 loaded with the Y453F peptide (NYNYLFRLF), and subsequently a ternary structure of the public TCRNYN-I complexed to the original NYN-HLA-A24 (NYNYLYRLF). Our structural analysis unveiled that despite competent presentation by HLA, the mutant Y453F peptide failed to establish a stable TCR-pHLA ternary complex due to reduced peptide: TCR contacts. This study supports the idea that cellular immunity restriction is an important driving force behind viral evolution.
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Epitopos de Linfócito T , Evasão da Resposta Imune , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Epitopos de Linfócito T/imunologia , Epitopos de Linfócito T/genética , SARS-CoV-2/imunologia , Linfócitos T CD8-Positivos/imunologia , COVID-19/imunologia , COVID-19/virologia , Receptores de Antígenos de Linfócitos T/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/química , Mutação , Cristalografia por Raios XRESUMO
Intestinal epithelial cells (IECs) are implicated in the propagation of T-cell-mediated inflammatory diseases, including graft-versus-host disease (GVHD), but the underlying mechanism remains poorly defined. Here, we report that IECs require receptor-interacting protein kinase-3 (RIPK3) to drive both gastrointestinal (GI) tract and systemic GVHD after allogeneic hematopoietic stem cell transplantation. Selectively inhibiting RIPK3 in IECs markedly reduces GVHD in murine intestine and liver. IEC RIPK3 cooperates with RIPK1 to trigger mixed lineage kinase domain-like protein-independent production of T-cell-recruiting chemokines and major histocompatibility complex (MHC) class II molecules, which amplify and sustain alloreactive T-cell responses. Alloreactive T-cell-produced interferon gamma enhances this RIPK1/RIPK3 action in IECs through a JAK/STAT1-dependent mechanism, creating a feed-forward inflammatory cascade. RIPK1/RIPK3 forms a complex with JAK1 to promote STAT1 activation in IECs. The RIPK1/RIPK3-mediated inflammatory cascade of alloreactive T-cell responses results in intestinal tissue damage, converting the local inflammation into a systemic syndrome. Human patients with severe GVHD showed highly activated RIPK1 in the colon epithelium. Finally, we discover a selective and potent RIPK1 inhibitor (Zharp1-211) that significantly reduces JAK/STAT1-mediated expression of chemokines and MHC class II molecules in IECs, restores intestinal homeostasis, and arrests GVHD without compromising the graft-versus-leukemia (GVL) effect. Thus, targeting RIPK1/RIPK3 in IECs represents an effective nonimmunosuppressive strategy for GVHD treatment and potentially for other diseases involving GI tract inflammation.
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Doença Enxerto-Hospedeiro , Intestinos , Camundongos , Humanos , Animais , Mucosa Intestinal/metabolismo , Inflamação/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Doença Enxerto-Hospedeiro/prevenção & controle , Doença Enxerto-Hospedeiro/metabolismo , Homeostase , Proteína Serina-Treonina Quinases de Interação com ReceptoresRESUMO
The Fenton-like process catalyzed by metal-free materials presents one of the most promising strategies to deal with the ever-growing environmental pollution. However, to develop improved catalysts with adequate activity, complicated preparation/modification processes and harsh conditions are always needed. Herein, we proposed an ultrafast and facile strategy to convert various inefficient commercial nanocarbons into highly active catalysts by noncovalent functionalization with polyethylenimine (PEI). The modified catalysts could be in situ fabricated by direct addition of PEI aqueous solution into the nanocarbon suspensions within 30 s and without any tedious treatment. The unexpectedly high catalytic activity is even superior to that of the single-atom catalyst and could reach as high as 400 times higher than the pristine carbon material. Theoretical and experimental results reveal that PEI creates net negative charge via intermolecular charge transfer, rendering the catalyst higher persulfate activation efficiency.
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SignificanceHydrogen peroxide is a highly competitive ready-to-use product for solar energy transformation. Nevertheless, the contemporary photosynthetic systems are not efficient enough, due to severe charge recombination caused by high activation energy and binding energy of the exciton. Herein, we achieve spontaneous exciton dissociation at room temperature. Moreover, the photosynthesis of H2O2 reaches between 9,366 and 12,324 µmol·g-1 from 9 AM to 4 PM in ambient conditions, that is, sunlight irradiation, real water including fresh water and seawater, room temperature, and open air. The ultrahigh photocatalytic efficiency in ambient conditions allows the solar-to-chemical conversion in a real cost-effective and sustainable way, which represents an important step toward real applications.
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BACKGROUND: Studies focused on pregnant women with congenital heart disease (CHD)-associated pulmonary hypertension (PH) are scarce and limited by small sample sizes and single-center design. This study sought to describe the pregnancy outcomes in women with CHD with and without PH. METHODS: Outcomes for pregnant women with CHD were evaluated retrospectively from 1993 to 2016 and prospectively from 2017 to 2019 from 7 tertiary hospitals. PH was diagnosed on the basis of echocardiogram or catheterization. The incidence of maternal death, cardiac complications, and obstetric and offspring complications was compared for women with CHD and no PH, mild, and moderate-to-severe PH. RESULTS: A total of 2220 pregnant women with CHD had completed pregnancies. PH associated with CHD was identified in 729 women, including 398 with mild PH (right ventricle to right atrium gradient 30-50 mm Hg) and 331 with moderate-to-severe PH (right ventricle to right atrium gradient >50 mm Hg). Maternal mortality occurred in 1 (0.1%), 0, and 19 (5.7%) women with CHD and no, mild, or moderate-to-severe PH, respectively. Of the 729 patients with PH, 619 (85%) had CHD-associated pulmonary arterial hypertension, and 110 (15%) had other forms of PH. Overall, patients with mild PH had better maternal outcomes than those with moderate-to-severe PH, including the incidence of maternal mortality or heart failure (7.8% versus 39.6%; P<0.001), other cardiac complications (9.0% versus 32.3%; P<0.001), and obstetric complications (5.3% versus 15.7%; P<0.001). Brain natriuretic peptide >100 ng/L (odds ratio, 1.9 [95% CI, 1.0-3.4], P=0.04) and New York Heart Association class III to IV (odds ratio, 2.9 [95% CI, 1.6-5.3], P<0.001) were independently associated with adverse maternal cardiac events in pregnancy with PH, whereas follow-up with a multidisciplinary team (odds ratio, 0.4 [95% CI, 0.2-0.6], P<0.001) and strict antenatal supervision (odds ratio, 0.5 [95% CI, 0.3-0.7], P=0.001) were protective. CONCLUSIONS: Women with CHD-associated mild PH appear to have better outcomes compared with women with CHD-associated moderate-to-severe PH, and with event rates similar for most outcomes with women with CHD and no PH. Multimodality risk assessment, including PH severity, brain natriuretic peptide level, and New York Heart Association class, may be useful in risk stratification in pregnancy with PH. Follow-up with a multidisciplinary team and strict antenatal supervision during pregnancy may also help to mitigate the risk of adverse maternal cardiac events.
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Cardiopatias Congênitas , Hipertensão Pulmonar , Complicações Cardiovasculares na Gravidez , Hipertensão Arterial Pulmonar , Gravidez , Feminino , Humanos , Masculino , Hipertensão Pulmonar/etiologia , Hipertensão Pulmonar/complicações , Gestantes , Estudos Retrospectivos , Peptídeo Natriurético Encefálico , Complicações Cardiovasculares na Gravidez/diagnóstico , Resultado da Gravidez , Cardiopatias Congênitas/diagnósticoRESUMO
Spatial immobilization of fragile enzymes using a nanocarrier is an efficient means to design heterogeneous biocatalysts, presenting superior stability and recyclability to pristine enzymes. An immobilized enzyme, however, usually compromises its catalytic activity because of inevasible mass transfer issues and the unfavorable conformation changes in a confined environment. Here, we describe a synergetic metal-organic framework pore-engineering strategy to trap lipase (an important hydrolase), which confers lipase-boosted stability and activity simultaneously. The hierarchically porous NU-1003, featuring interconnected mesopore and micropore channels, is precisely modified by chain-adjustable fatty acids on its mesopore channel, into which lipase is trapped. The interconnected pore structure ensures efficient communication between trapped lipase and exterior media, while the fatty acid-mediated hydrophobic pore can activate the opening conformation of lipase by interfacial interaction. Such dual pore compartmentalization and hydrophobization activation effects render the catalytic center of trapped lipase highly accessible, resulting in 1.57-fold and 2.46-fold activities as native lipase on ester hydrolysis and enantioselective catalysis. In addition, the feasibility of these heterogeneous biocatalysts for kinetic resolution of enantiomer is also validated, showing much higher efficiency than native lipase.
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Estabilidade Enzimática , Enzimas Imobilizadas , Interações Hidrofóbicas e Hidrofílicas , Lipase , Lipase/química , Lipase/metabolismo , Porosidade , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Estruturas Metalorgânicas/química , Hidrólise , BiocatáliseRESUMO
BACKGROUND: Evidence has demonstrated that monitoring of the variable, diversity, and joining gene segments (VDJ) rearrangement of the immunoglobulin (Ig) genes in the circulating tumor DNA (ctDNA) is of value in predicting the outcomes of diffuse large B cell lymphoma (DLBCL). In this study, we investigated the role of VDJ rearrangement proportion in ctDNA for predicting DLBCL progression. METHODS: Patients diagnosed with newly diagnosed DLBCL were included in this study. The VDJ sequences of IgH were detected using next-generation sequencing (NGS) in formalin-fixed paraffin-embedded tissue and/or peripheral blood. The clonotype of the highest proportion in the peripheral blood was defined as the "dominant circulating clonotype," whilst the clonotype of the highest proportion in matched tissue that is detected in peripheral blood was defined as the "dominant tissue-matched clonotype." The decision tree, a machine learning-based methodology, was used to establish a progression-predicting model through a combination of "dominant tissue-matched clonotype" proportion or "dominant circulating clonotype" proportion, and the clinicopathological information, including age, sex, cell of origin, stage, international prognostic index, lactate dehydrogenase, number of extranodal involvements and ß2-microglobulin. RESULTS: A total of 55 patients with eligible sequencing data were used for prognosis analysis, among which 36 patients had matched tissue samples. The concordance rate of "dominant circulating clonotype" and "dominant tissue-matched clonotype" was 19.44% (7/36). The decision tree model showed that the combination of extranodal involvement event and "dominant circulating clonotype" proportion (≥37%) had a clinical value in predicting the prognosis of DLBCL following combined chemotherapy (sensitivity, 0.63; specificity, 0.81; positive prediction value (PPV), 0.59; negative prediction value, 0.83; kappa value, 0.42). Noticeably, the combination of the "dominant tissue-matched clonotype" and extranodal involvement event showed a higher value in predicting the progression (sensitivity, 0.85; specificity, 0.78; PPV, 0.69; kappa value, 0.64). CONCLUSION: IgH proportion detected in the ctDNA samples traced from tissue samples has a high clinical value in predicting the progression of DLBCL.
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DNA Tumoral Circulante , Progressão da Doença , Linfoma Difuso de Grandes Células B , Humanos , Linfoma Difuso de Grandes Células B/genética , Linfoma Difuso de Grandes Células B/patologia , Linfoma Difuso de Grandes Células B/sangue , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Masculino , Feminino , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Pessoa de Meia-Idade , Idoso , Adulto , Prognóstico , Idoso de 80 Anos ou mais , Cadeias Pesadas de Imunoglobulinas/genética , Rearranjo GênicoRESUMO
Sample preparation is an inevitable step in the screening workflow for the identification of unknown pollutants in the aquatic environment. However, the possible loss of pollutants during sample preparation has aroused serious concern but remains not effectively resolved. This study shows that high-risk pollutants omitted in solid-phase extraction (SPE) can be identified via in situ thin-film microextraction (TFME) coupled with high-resolution mass spectrometry. It was observed that a total of 541 features showed higher mass spectrometry signal intensity by using in situ TFME in comparison with SPE. Subsequently, 28 compounds were identified from the features with higher intensity by comparing the recorded tandem mass spectra with the online database and validating with standards. Notably, six out of these compounds were completely omitted using SPE, including a dye, drug, and industrial product. It was confirmed that the lower extraction efficiencies of SPE were attributed to the limited sample volumes, the losses of compounds during sample transportation and storage, and the entrapment of compounds in SPE columns. This study demonstrates that in situ TFME should be used as a supplementary technique to SPE for extending the coverage of pollutants in the screening workflows.
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Uranyl ions (UO22+) are recognized as important indicators for monitoring sudden nuclear accidents. However, the interferences coexisting in the complicated environmental matrices impart serious constraints on the reliability of current on-site monitoring methods. Herein, a novel ratiometric method for the highly sensitive and selective detection of UO22+ is reported based on a [Eu(diaminoterephthalic acid)] (Eu-DATP) metal-organic framework. Benefiting from the unique chemical structure of Eu-DATP, energy transfer from DATP to UO22+ was enabled, resulting in the up-regulated fluorescence of UO22+ and the simultaneous down-regulated fluorescence of Eu3+. The limit of detection reached as low as 2.7 nM, which was almost 2 orders of magnitude below the restricted limit in drinking water set by the United States Environmental Protection Agency (130 nM). The Eu-DATP probe showed excellent specificity to UO22+ over numerous interfering species, as the intrinsic emissions of UO22+ were triggered. This unprecedentedly high selectivity is especially beneficial for monitoring UO22+ in complicated environmental matrices with no need for tedious sample pretreatment, such as filtration and digestion. Then, by facilely equipping a Eu-DATP-based sampler on a drone, remotely controlled sampling and on-site analysis in real water samples were realized. The concentrations of UO22+ were determined to be from 16.5 to 23.5 nM in the river water of the Guangzhou downtown area, which was consistent with the results determined by the gold-standard inductively coupled plasma mass spectrometry. This study presents a reliable and convenient method for the on-site analysis of UO22+.
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This work reports on the emergence of quantum Griffiths singularity (QGS) associated with the magnetic field induced superconductor-metal transition (SMT) in unconventional Nd_{0.8}Sr_{0.2}NiO_{2} infinite layer superconducting thin films. The system manifests isotropic SMT features under both in-plane and perpendicular magnetic fields. Importantly, after scaling analysis of the isothermal magnetoresistance curves, the obtained effective dynamic critical exponents demonstrate divergent behavior when approaching the zero-temperature critical point B_{c}^{*}, identifying the QGS characteristics. Moreover, the quantum fluctuation associated with the QGS can quantitatively explain the upturn of the upper critical field around zero temperature for both the in-plane and perpendicular magnetic fields in the phase boundary of SMT. These properties indicate that the QGS in the Nd_{0.8}Sr_{0.2}NiO_{2} superconducting thin film is isotropic. Moreover, a higher magnetic field gives rise to a metallic state with the resistance-temperature relation R(T) exhibiting lnT dependence among the 2-10 K range and T^{2} dependence of resistance below 1.5 K, which is significant evidence of Kondo scattering. The interplay between isotropic QGS and Kondo scattering in the unconventional Nd_{0.8}Sr_{0.2}NiO_{2} superconductor can illustrate the important role of rare region in QGS and help to uncover the exotic superconductivity mechanism in this system.
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AIM: To explore the risk of major adverse cardiovascular events (MACE) associated with exposure to bexagliflozin. METHODS: The analysis included 4090 participants with type 2 diabetes (T2D) enrolled in nine phase 2 and 3 double-blind randomized controlled trials. All potential MACE were adjudicated by a blinded committee. The primary endpoint for the meta-analysis was the hazard ratio (HR) for the time to first occurrence of non-fatal stroke, non-fatal myocardial infarction (MI), cardiovascular (CV) death or hospitalization for unstable angina (MACE+), tested for non-inferiority to a ratio of 1.8. The secondary endpoints were time to first occurrence of (i) non-fatal stroke, non-fatal MI or CV death (MACE), tested for non-inferiority to a ratio of 1.3; and (ii) CV death or hospitalization for heart failure, tested for superiority. RESULTS: The HR for the primary endpoint of MACE+ was 0.80 (95% confidence interval [CI] 0.58, 1.09), which fulfilled the non-inferiority objective with a P value of less than 0.0001. Non-inferiority for the first key secondary endpoint of MACE was also shown (HR = 0.82; 95% CI 0.59, 1.13; P = 0.0023). Superiority for time to CV death or first hospitalization for heart failure was not shown. CONCLUSIONS: Bexagliflozin did not increase the risk of MACE in participants with T2D when compared with placebo or active control. Both the preapproval and postapproval thresholds for CV safety were met and bexagliflozin has been approved by the US Food and Drug Administration.
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Doenças Cardiovasculares , Sistema Cardiovascular , Diabetes Mellitus Tipo 2 , Insuficiência Cardíaca , Infarto do Miocárdio , Piranos , Acidente Vascular Cerebral , Adulto , Humanos , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/induzido quimicamente , Infarto do Miocárdio/epidemiologia , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/complicações , Acidente Vascular Cerebral/epidemiologia , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Hipoglicemiantes/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
BACKGROUND: Pasteurella multocida is a zoonotic pathogen that mainly causes local skin and soft tissue infections in the human body through cat and dog bites. It rarely causes bacteraemia (or sepsis) and meningitis. We reported a case of septic shock and meningitis caused by P. multocida in a patient without a history of cat and dog bites. CASE PRESENTATION: An 84-year-old male patient was urgently sent to the emergency department after he was found with unclear consciousness for 8 h, accompanied by limb tremors and urinary incontinence. In the subsequent examination, P. multocida was detected in the blood culture and wound secretion samples of the patient. However, it was not detected in the cerebrospinal fluid culture, but its DNA sequence was detected. Therefore, the patient was clearly diagnosed with septic shock and meningitis caused by P. multocida. The patient had no history of cat or dog contact or bite. The patient was subsequently treated with a combination of penicillin G, doxycycline, and ceftriaxone, and he was discharged after 35 days of hospitalisation. CONCLUSION: This report presented a rare case of septic shock and meningitis caused by P. multocida, which was not related to a cat or dog bite. Clinical doctors should consider P. multocida as a possible cause of sepsis or meningitis and should be aware of its potential seriousness even in the absence of animal bites.
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Mordeduras e Picadas , Meningite , Infecções por Pasteurella , Pasteurella multocida , Choque Séptico , Masculino , Humanos , Animais , Cães , Gatos , Idoso de 80 Anos ou mais , Infecções por Pasteurella/diagnóstico , Infecções por Pasteurella/tratamento farmacológico , Choque Séptico/etiologia , Choque Séptico/complicações , Meningite/complicações , Mordeduras e Picadas/complicaçõesRESUMO
OBJECTIVE: To construct a nutrition support program for middle-aged and elderly patients with acute decompensated heart failure (ADHF) during hospitalization. METHODS: Based on the JBI Evidence-Based Health Care Model as the theoretical framework, the best evidence was extracted through literature analysis and a preliminary nutrition support plan for middle-aged and elderly ADHF patients during hospitalization was formed. Two rounds of expert opinion consultation were conducted using the Delphi method. The indicators were modified, supplemented and reduced according to the expert's scoring and feedback, and the expert scoring was calculated. RESULTS: The response rates of the experts in the two rounds of consultation were 86.7% and 100%, respectively, and the coefficient of variation (CV) for each round was between 0.00% and 29.67% (all < 0.25). In the first round of expert consultation, 4 items were modified, 3 items were deleted, and 3 items were added. In the second round of the expert consultation, one item was deleted and one item was modified. Through two rounds of expert consultation, expert consensus was reached and a nutrition support plan for ADHF patients was finally formed, including 4 first-level indicators, 7 s-level indicators, and 24 third-level indicators. CONCLUSION: The nutrition support program constructed in this study for middle-aged and elderly ADHF patients during hospitalization is authoritative, scientific and practical, and provides a theoretical basis for clinical development of nutrition support program for middle-aged and elderly ADHF patients during hospitalization.
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Insuficiência Cardíaca , Apoio Nutricional , Apoio Nutricional/métodos , Insuficiência Cardíaca/dietoterapia , Doença Aguda , Humanos , Idoso , Prática Clínica Baseada em Evidências , Hospitalização , Masculino , FemininoRESUMO
Although LINC00313 is dysregulated in several tumors, its role in head and neck squamous cell carcinoma (HNSC) is not fully understood. The aim of this study was to analyze the role of LINC00313 in HNSC. The clinical information and LINC00313 expression data of HNSC were mined from the TCGA/GEO/cbioportal database. The correlation between LINC00313 expression and immune cell infiltration in HNSC tumors was analyzed by bioinformatics and gene enrichment analysis was performed. LINC00313 was silenced in HNSC cell lines, and changes at the genetic and molecular levels were verified through qRT-PCR and Western blotting. The researchers also validated its functional phenotype through a series of cell function experiments. The results showed that overexpression and copy number variation of LINC00313 in HNSC were associated with poorer prognosis. In addition, LINC00313 expression was significantly negatively correlated with immune cell infiltration. Silencing of LINC00313 in HNSC cells significantly reduced the rate of cell migration. LINC00313 may affect the progression of HNSC by regulating epithelial-mesenchymal transition. In conclusion, LINC00313 is a potential biomarker of HNSC prognosis and a potential target for immunotherapy.
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Variações do Número de Cópias de DNA , Neoplasias de Cabeça e Pescoço , Humanos , Biomarcadores , Transição Epitelial-Mesenquimal/genética , Neoplasias de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , RNA Longo não CodificanteRESUMO
BACKGROUND: Spermatogonial stem cells (SSCs) are essential for the maintenance and initiation of male spermatogenesis. Despite the advances in understanding SSC biology in mouse models, the mechanisms underlying human SSC development remain elusive. RESULTS: Here, we analyzed the signaling pathways involved in SSC regulation by testicular somatic cells using single-cell sequencing data (GEO datasets: GSE149512 and GSE112013) and identified that Leydig cells communicate with SSCs through pleiotrophin (PTN) and its receptor syndecan-2 (SDC2). Immunofluorescence, STRING prediction, and protein immunoprecipitation assays confirmed the interaction between PTN and SDC2 in spermatogonia, but their co-localization was observed only in approximately 50% of the cells. The knockdown of SDC2 in human SSC lines impaired cell proliferation, DNA synthesis, and the expression of PLZF, a key marker for SSC self-renewal. Transcriptome analysis revealed that SDC2 knockdown downregulated the expression of GFRA1, a crucial factor for SSC proliferation and self-renewal, and inhibited the HIF-1 signaling pathway. Exogenous PTN rescued the proliferation and GFRA1 expression in SDC2 knockdown SSC lines. In addition, we found downregulation of PTN and SDC2 as well as altered localization in non-obstructive azoospermia (NOA) patients, suggesting that downregulation of PTN and SDC2 may be associated with impaired spermatogenesis. CONCLUSIONS: Our results uncover a novel mechanism of human SSC regulation by the testicular microenvironment and suggest a potential therapeutic target for male infertility.
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Proteínas de Transporte , Proliferação de Células , Citocinas , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial , Células Intersticiais do Testículo , Sindecana-2 , Masculino , Humanos , Proliferação de Células/fisiologia , Células Intersticiais do Testículo/metabolismo , Citocinas/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Receptores de Fator Neurotrófico Derivado de Linhagem de Célula Glial/genética , Sindecana-2/metabolismo , Sindecana-2/genética , Proteínas de Transporte/metabolismo , Proteínas de Transporte/genética , Sobrevivência Celular/fisiologia , Espermatogônias/metabolismo , Transdução de Sinais/fisiologia , Células-Tronco Germinativas Adultas/metabolismo , Células-Tronco Germinativas Adultas/fisiologiaRESUMO
Photosynthesis of hydrogen peroxide (H2O2) in ambient conditions remains neither cost effective nor environmentally friendly enough because of the rapid charge recombination. Here, a photocatalytic rate of as high as 114 µmolâ g-1â h-1 for the production of H2O2 in pure water and open air is achieved by using a Z-scheme heterojunction, which outperforms almost all reported photocatalysts under the same conditions. An extensive study at the atomic level demonstrates that Z-scheme electron transfer is realized by improving the photoresponse of the oxidation semiconductor under visible light, when the difference between the Fermi levels of the two constituent semiconductors is not sufficiently large. Moreover, it is verified that a type II electron transfer pathway can be converted to the desired Z-scheme pathway by tuning the excitation wavelengths. This study demonstrates a feasible strategy for developing efficient Z-scheme photocatalysts by regulating photoresponses.
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Artificial photosynthesis in ambient conditions is much less efficient than the solar-to-biomass conversion (SBC) processes in nature. Here, we successfully mimic the NADP-mediated photosynthetic processes in green plants by introducing redox moieties as the electron acceptors in the present conjugated polymeric photocatalyst. The current artificial process substantially promotes the charge carrier separation efficiency and the oxygen reduction efficiency, achieving a photosynthesis rate for converting Earth-abundant water and oxygen in air into hydrogen peroxide as high as 909 µmolâ g-1â h-1 and a solar-to-chemical conversion (SCC) efficiency up to 0.26%. The SCC efficiency is more than two times higher than the average SBC efficiency in nature (0.1%) and the highest value under ambient conditions. This study presents a strategy for efficient SCC in the future.
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Fotossíntese/fisiologia , Biomassa , Biomimética/métodos , Catálise , Peróxido de Hidrogênio/química , NADP , Oxirredução , Oxigênio/química , Processos Fotoquímicos , Polímeros/química , Energia Solar , Luz Solar , Água/químicaRESUMO
Objective: To analyze the potential factors influencing the diagnostic capability of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and provide medication treatment recommendations for patients with pancreatic solid mass lesions. Methods: A retrospective analysis was conducted on clinical data of 92 patients with pancreatic solid mass lesions who underwent EUS-FNA examination after detection by imaging studies. The diagnostic effectiveness of EUS-FNA was evaluated based on cytological or histological examination results. Logistic regression analysis was subsequently performed to analyze the potential factors influencing the diagnostic capability of EUS-FNA in patients with pancreatic solid mass lesions. Results: EUS-FNA was successfully performed in all 92 patients, with a puncture success rate of 100.00%. Only one patient experienced transient hyperamylasemia, which resolved with conservative treatment. No other serious complications were observed. Among the 92 patients, 70 patients obtained a definite diagnosis after EUS-FNA (Group A), while 22 patients did not achieve a definite diagnosis (Group B) after the procedure. Univariate analysis showed that lesion size, dilation of the pancreatic duct or bile duct, negative pressure, and suction method were significantly different between Group A and Group B (P < .05). Multivariate logistic regression analysis revealed that lesion size, dilation of the pancreatic duct or bile duct, negative pressure, and suction method were potential factors influencing the diagnostic ability of EUS-FNA in patients with solid pancreatic lesions (P < .05). Conclusion: EUS-FNA has a high diagnostic value in the evaluation of solid pancreatic lesions. Lesion size, dilation of the pancreatic duct or bile duct, negative pressure, and suction method are potential factors influencing the diagnostic ability of EUS-FNA in patients with solid pancreatic lesions. In terms of medical treatment, specific treatment methods and drug choices should be based on a comprehensive evaluation of the nature of the patient's lesions and the severity of the condition.
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Skin cutaneous melanoma (SKCM) is the most life-threatening skin cancer and lacks early detection and effective treatment strategies. Many long noncoding RNAs are associated with the development of tumors and may serve as potential immunotherapeutic targets. In this study, microarray analysis was performed to screen for differentially expressed lncRNAs between SKCM and normal tissues, and SMG7-AS1 was identified as an upregulated lncRNA in SKCM. Subsequently, bioinformatic analysis revealed that dysregulation of SMG7-AS1 influences metastasis and immune infiltration. qRT-PCR of clinical samples demonstrated that the expression of SMG7-AS1 was higher in melanoma tissues. Flow cytometry showed that SMG7-AS1 plays a vital role in the cell cycle. Additionally, SMG7-AS1 was found to be associated with immunotherapy responses. To the best of our knowledge, this study is the first to report that SMG7-AS1 is associated with SKCM and may serve as a prognostic biomarker and predictor of immunotherapy responses in SKCM.