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Follicular helper T (TFH) cells are a specialized subset of CD4+ T cells that essentially support germinal center responses where high-affinity and long-lived humoral immunity is generated. The regulation of TFH cell survival remains unclear. Here we report that TFH cells show intensified lipid peroxidation and altered mitochondrial morphology, resembling the features of ferroptosis, a form of programmed cell death that is driven by iron-dependent accumulation of lipid peroxidation. Glutathione peroxidase 4 (GPX4) is the major lipid peroxidation scavenger and is necessary for TFH cell survival. The deletion of GPX4 in T cells selectively abrogated TFH cells and germinal center responses in immunized mice. Selenium supplementation enhanced GPX4 expression in T cells, increased TFH cell numbers and promoted antibody responses in immunized mice and young adults after influenza vaccination. Our findings reveal the central role of the selenium-GPX4-ferroptosis axis in regulating TFH homeostasis, which can be targeted to enhance TFH cell function in infection and following vaccination.
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Ferroptose/fisiologia , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Selênio/farmacologia , Células T Auxiliares Foliculares/fisiologia , Adolescente , Adulto , Animais , Sobrevivência Celular/imunologia , Criança , Feminino , Centro Germinativo/citologia , Centro Germinativo/imunologia , Homeostase/efeitos dos fármacos , Homeostase/genética , Humanos , Imunidade Humoral/imunologia , Vacinas contra Influenza/imunologia , Peroxidação de Lipídeos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/fisiologia , Ovalbumina , Células T Auxiliares Foliculares/imunologia , Vacinação , Adulto JovemRESUMO
Activation of natural killer (NK) cells by hematopoietic target cells is controlled by the SLAM family of receptors and by the associated SAP family of adaptors. Here we found that SLAM receptors also enhanced NK cell activation by nonhematopoietic target cells, which lack ligands for SLAM receptors. This function was mediated by SLAMF6, a homotypic SLAM receptor found on NK cells and other hematopoietic cells, and was regulated by SAP adaptors, which uncoupled SLAM receptors from phosphatase SHP-1 and diminished the effect of SLAMF6 on NK cell responsiveness toward nonhematopoietic cells. Thus, in addition to their role in NK cell activation by hematopoietic cells, the SLAM-SAP pathways influence responsiveness toward nonhematopoietic targets by a process akin to NK cell 'education'.
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Antígenos CD/imunologia , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Células Matadoras Naturais/imunologia , Proteína Tirosina Fosfatase não Receptora Tipo 6/imunologia , Receptores de Superfície Celular/imunologia , Transferência Adotiva , Animais , Linhagem Celular Tumoral , Células HeLa , Humanos , Imunidade Inata , Ativação Linfocitária , Melanoma Experimental , Camundongos , Transdução de Sinais , Proteína Associada à Molécula de Sinalização da Ativação Linfocitária , Família de Moléculas de Sinalização da Ativação Linfocitária , Membro 1 da Família de Moléculas de Sinalização da Ativação LinfocitáriaRESUMO
OBJECTIVE: To compare the effects of peritoneal dialysis and hemodialysis on spontaneous brain activity in patients with end-stage renal disease. METHODS: A total of 52 dialysis patients with end-stage renal disease, including 25 patients with chronic kidney disease undergoing hemodialysis (HD-CKD) and 27 patients with chronic kidney disease undergoing peritoneal dialysis (PD-CKD), and 49 healthy controls (normal control) were included. All participants underwent neuropsychological testing (Mini-Mental State Examination and Montreal cognitive assessment) and resting-state functional magnetic resonance imaging. Fractional amplitude of low frequency fluctuations and Regional Homogeneity algorithms were employed to evaluate spontaneous brain activity. Statistical analysis was performed to discern differences between the groups. RESULTS: When compared with the normal control group, the PD-CKD group exhibited significant alterations in fractional amplitude of low frequency fluctuations in various cerebellum regions and other brain areas, while the HD-CKD group showed decreased fractional amplitude of low frequency fluctuations in the bilateral pericalcarine cortex. The Regional Homogeneity values in the PD-CKD group were notably different than those in the normal control group, particularly in regions such as the bilateral caudate nucleus and the right putamen. CONCLUSION: Both peritoneal dialysis and hemodialysis modalities impact brain activity, but manifest differently in end-stage renal disease patients. Understanding these differences is crucial for optimizing patient care.
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Falência Renal Crônica , Diálise Peritoneal , Insuficiência Renal Crônica , Humanos , Imageamento por Ressonância Magnética/métodos , Diálise Renal , Encéfalo , Insuficiência Renal Crônica/diagnóstico por imagem , Insuficiência Renal Crônica/terapia , Insuficiência Renal Crônica/patologia , Falência Renal Crônica/terapia , Falência Renal Crônica/patologiaRESUMO
While linear ubiquitin plays critical roles in multiple cell signaling pathways, few substrates have been identified. Global profiling of linear ubiquitin substrates represents a significant challenge because of the low endogenous level of linear ubiquitination and the background interference arising from highly abundant ubiquitin linkages (e.g. K48- and K63-) and from the non-specific attachment of interfering proteins to the linear polyubiquitin chain. We developed a bio-orthogonal linear ubiquitin probe by site-specific encoding of a norbornene amino acid on ubiquitin (NAEK-Ub). This probe facilitates covalent labeling of linear ubiquitin substrates in live cells and enables selective enrichment and identification of linear ubiquitin-modified proteins. Given the fact that the frequent overexpression of the linear linkage-specific deubiquitinase OTULIN correlates with poor prognosis in glioblastoma, we demonstrated the feasibility of the NAEK-Ub strategy by identifying and validating substrates of linear ubiquitination in patient-derived glioblastoma stem-like cells (GSCs). We identified STAT3 as a bona fide substrate of linear ubiquitin, and showed that linear ubiquitination negatively regulates STAT3 activity by recruitment of the phosphatase TC-PTP to STAT3. Furthermore, we demonstrated that preferential expression of OTULIN in GSCs restricts linear ubiquitination on STAT3 and drives persistent STAT3 signaling, and thereby maintains the stemness and self-renewal of GSCs.
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Glioblastoma , Fator de Transcrição STAT3 , Ubiquitina , Humanos , Poliubiquitina/genética , Transdução de Sinais , Fator de Transcrição STAT3/metabolismo , Ubiquitina/metabolismo , UbiquitinaçãoRESUMO
Methamphetamine use disorder (MAUD) can substantially jeopardize public security due to its high-risk social psychology and behaviour. Given that the dopamine reward system is intimately correlated with MAUD, we investigated the association of single nucleotide polymorphisms (SNPs), as well as methylation status of dopamine receptor type 4 (DRD4), catechol-O-methyltransferase (COMT) genes, and paranoid and motor-impulsive symptoms in MAUD patients. A total of 189 MAUD patients participated in our study. Peripheral blood samples were used to detect 3 SNPs and 35 CpG units of methylation in the DRD4 gene promoter region and 5 SNPs and 39 CpG units in the COMT gene. MAUD patients with the DRD4 rs1800955 C allele have a lower percentage of paranoid symptoms than those with the rs1800955 TT allele. Individuals with paranoid symptoms exhibited a reduced methylation degree at a particular DRD4 CpG2.3 unit. The interaction of the DRD4 rs1800955 C allele and the reduced DRD4CpG2.3 methylation degree were associated with a lower occurrence of paranoid symptoms. Meanwhile, those with the COMT rs4818 CC allele had lower motor-impulsivity scores in MAUD patients but greater COMT methylation levels in the promoter region and methylation degree at the COMT CpG 51.52 unit. Therefore, based only on the COMT rs4818 CC polymorphism, there was a negative correlation between COMT methylation and motor-impulsive scores. Our preliminary results provide a clue that the combination of SNP genotype and methylation status of the DRD4 and COMT genes serve as biological indicators for the prevalence of relatively high-risk psychotic symptoms in MAUD patients.
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Metanfetamina , Polimorfismo de Nucleotídeo Único , Humanos , Catecol O-Metiltransferase/genética , Dopamina , Metanfetamina/efeitos adversos , Genótipo , MetilaçãoRESUMO
BACKGROUND: Evidence from observational studies indicates that lung cancer screening (LCS) guidelines with high rates of lung cancer (LC) underdiagnosis, and although current screening guidelines have been updated and eligibility criteria for screening have been expanded, there are no studies comparing the efficiency of LCS guidelines in Chinese population. METHODS: Between 2005 and 2022, 31,394 asymptomatic individuals were screened using low-dose computed tomography (LDCT) at our institution. Demographic data and relevant LC risk factors were collected. The efficiency of the LCS for each guideline criteria was expressed as the efficiency ratio (ER). The inclusion rates, eligibility rates, LC detection rates, and ER based on the different eligibility criteria of the four guidelines were comparatively analyzed. The four guidelines were as follows: China guideline for the screening and early detection of lung cancer (CGSL), the National Comprehensive Cancer Network (NCCN), the United States Preventive Services Task Force (USPSTF), and International Early Lung Cancer Action Program (I-ELCAP). RESULTS: Of 31,394 participants, 298 (155 women, 143 men) were diagnosed with LC. For CGSL, NCCN, USPSTF, and I-ELCAP guidelines, the eligibility rates for guidelines were 13.92%, 6.97%, 6.81%, and 53.46%; ERe for eligibility criteria were 1.46%, 1.64%, 1.51%, and 1.13%, respectively; and for the inclusion rates, they were 19.0%, 9.5%, 9.3%, and 73.0%, respectively. LCs which met the screening criteria of CGSL, NCCN, USPSTF, and I-ELCAP guidelines were 29.2%, 16.4%, 14.8%, and 86.6%, respectively. The age and smoking criteria for CGSL were stricter, hence resulting in lower rates of LC meeting the screening criteria. The CGSL, NCCN, and USPSTF guidelines showed the highest underdiagnosis in the 45-49 age group (17.4%), while the I-ELCAP guideline displayed the highest missed diagnosis rate (3.0%) in the 35-39 age group. Males and females significantly differed in eligibility based on the criteria of the four guidelines (P < 0.001). CONCLUSIONS: The I-ELCAP guideline has the highest eligibility rate for both males and females. But its actual efficiency ratio for those deemed eligible by the guideline was the lowest. Whereas the NCCN guideline has the highest ERe value for those deemed eligible by the guideline.
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Detecção Precoce de Câncer , Neoplasias Pulmonares , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico , Masculino , China , Feminino , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas , Pessoa de Meia-Idade , Detecção Precoce de Câncer/métodos , Detecção Precoce de Câncer/normas , Idoso , Guias de Prática Clínica como Assunto , Programas de Rastreamento/métodos , Programas de Rastreamento/normas , AdultoRESUMO
Resident memory T (Trm) cells which are specifically located in non-lymphoid tissues showed distinct phenotypes and functions compared to circulating memory T cells and were vital for the initiation of robust immune response within tissues. However, the heterogeneity in the transcriptional features, development pathways, and cancer response of Trm cells in the small intestine was not demonstrated. Here, we integrated scRNA-seq and scTCR-seq data pan-tissue T cells to explore the heterogeneity of Trm cells and their development pathways. Trm were enriched in tissue-specific immune response and those in the DUO specially interacted with B cells via TNF and MHC-I signatures. T cell lineage analyses demonstrated that Trm might be derived from the T_CD4/CD8 subset within the same organ or migrated from spleen and mesenteric lymph nodes. We compared the immune repertoire of Trm among organs and implied that clonotypes in both DUO and ILE were less expanded and hydrophilic TRB CDR3s were enriched in the DUO. We further demonstrated that Trm in the intestine infiltrated the colorectal cancer and several effector molecules were highly expressed. Finally, the TCGA dataset of colorectal cancer implied that the infiltration of Trm from the DUO and the ILE was beneficial for overall survival and the response to immune checkpoint blockade.
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Neoplasias Colorretais , Memória Imunológica , Humanos , Células T de Memória , Relevância Clínica , Linfócitos T CD8-Positivos , Intestino Delgado , Análise de Célula Única , Neoplasias Colorretais/metabolismoRESUMO
BACKGROUND: Although low-dose computed tomography (LDCT) screening effectively reduces LC mortality in high-risk individuals with a history of smoking in China, the feasibility and efficacy of lung cancer screening (LCS) in individuals who never smoked versus individuals who smoked remains unclear. METHODS: We conducted a retrospective analysis of prospective cohort studies at the National Cancer Center (NCC) in China from January 2006 to December 2022. A comprehensive LCS initiative was undertaken, involving 30,468 participants (54.5% male). Participants underwent LCS using LDCT. Potential malignancies were managed through joint consensus between patients and their physicians. Epidemiology, screening eligibility criteria, and LC detection rates and survival outcomes were compared between individuals who smoked and individuals who never smoked. RESULTS: Among 30,468 participants, 339 LCs were pathologically confirmed in 289 patients. The LC detection rate was 0.9% (289/30,468) overall, 0.8% in individuals who smoked (71/9,042), and 1.0% in individuals who never smoked (218/21,426). In individuals who smoked, LC detection rates were 0.5% (21/4516) and 1.1% (50/4526) in the < 20 and ≥ 20 pack-year subgroups, respectively (P = 0.001). Early-stage LC (stage 0 or I) was detected in 73.8% of the individuals who smoked and in 78.8% of individuals who never smoked, while advanced LC (stage III-IV) was found 8.8% of individuals who smoked and 4.2% of individuals who never smoked, respectively. Significant differences in histologic types were found between individuals who smoked and individuals who never smoked (P = 0.01), although adenocarcinoma was the most prevalent in both groups, at 83.0% and 78.8%, respectively. The median nodule size was 9.9 mm (IQR, 8.0-13.8) in individuals who smoked and 9.2 mm (IQR, 6.8-13.6) in individuals who never smoked (P = 0.228). Individuals who never smoked tended to favour surgical treatment alone (88.0%) more than individuals who smoked (81.3%). The 10-year survival rate was higher in individuals who never smoked (92.6%) than in individuals who smoked (88.8%). Only 15.6% (45/289) of patients with LC met the United States Preventive Services Task Force (USPSTF) criteria for LDCT eligibility, while 29.0% (84/289) met the China guideline for the screening and early detection of lung cancer (CGSL) criteria. Median follow-up for those followed was 25.4 (IQR, 13.7-43.3) months. CONCLUSIONS: LDCT screening improves early LC detection and treatment outcomes for both individuals who smoked and individuals who never smoked. Significant differences exist in epidemiology, histologic type, and survival between these groups. The USPSTF and CGSL criteria miss a significant number of LC cases, particularly among individuals who never smoked. Integrating individuals who never smoked into LCS programs is essential, yet it comes with its own challenges, such as managing radiation risks, allocating resources effectively, and considering financial aspects. Consequently, there is an urgent need for LCS programs in China to better identify the "high-risk" non-smoker population susceptible to LC and to ensure that potential risks associated with screening are reduced.
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Detecção Precoce de Câncer , Neoplasias Pulmonares , não Fumantes , Fumantes , Tomografia Computadorizada por Raios X , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , China/epidemiologia , Detecção Precoce de Câncer/métodos , Tomografia Computadorizada por Raios X/métodos , Fumantes/estatística & dados numéricos , Idoso , Estudos Retrospectivos , não Fumantes/estatística & dados numéricos , Fumar/efeitos adversos , Fumar/epidemiologia , Estudos Prospectivos , AdultoRESUMO
BACKGROUND: Preoperative differentiation of the types of mediastinal tumors is essential. Magnetic resonance (MR) elastography potentially provides a noninvasive method to assess the classification of mediastinal tumor subtypes. PURPOSE: To evaluate the use of MR elastography in anterior mediastinal masses and to characterize the mechanical properties of tumors of different subtypes. STUDY TYPE: Prospective. SUBJECTS: 189 patients with anterior mediastinal tumors (AMTs) confirmed by histopathology (62 thymomas, 53 thymic carcinomas, 57 lymphomas, and 17 germ cell tumors). FIELD STRENGTH/SEQUENCE: A gradient echo-based 2D MR elastography sequence and a diffusion-weighted imaging (DWI) sequence at 3.0 T. ASSESSMENT: Stiffness and apparent diffusion coefficients (ADC) were measured in AMTs using MR elastography-derived elastograms and DWI-derived ADC maps, respectively. The aim of this study is to identify whether MR elastography can differentiate between the histological subtypes of ATMs. STATISTICAL TESTS: One-way analysis of variance (ANOVA), two-way ANOVA, Pearson's linear correlation coefficient (r), receiver operating characteristic (ROC) curve analysis; P < 0.05 was considered significant. RESULTS: Lymphomas had significantly lower stiffness than other AMTs (4.0 ± 0.63 kPa vs. 4.8 ± 1.39 kPa). The mean stiffness of thymic carcinomas was significantly higher than that of other AMTs (5.6 ± 1.41 kPa vs. 4.2 ± 0.94 kPa). Using a cutoff value of 5.0 kPa, ROC analysis showed that lymphomas could be differentiated from other AMTs with an accuracy of 59%, sensitivity of 97%, and specificity of 38%. Using a cutoff value of 5.1 kPa, thymic carcinomas could be differentiated from other AMTs with an accuracy of 84%, sensitivity of 67%, and specificity of 90%. However, there was an overlap in the stiffness values of individual thymomas (4.2 ± 0.71; 3.9-4.5), thymic carcinomas (5.6 ± 1.41; 5.0-6.1), lymphomas (4.0 ± 0.63; 3.8-4.2), and germ cell tumors (4.5 ± 1.79; 3.3-5.6). DATA CONCLUSION: MR elastography-derived stiffness may be used to evaluate AMTs of various histologies. TECHNICAL EFFICACY: Stage 2.
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Post-traumatic stress disorder (PTSD) is a debilitating mental health disease related to traumatic experience, and its treatment outcomes are unsatisfactory. Accumulating research has indicated that cannabidiol (CBD) exhibits anti-PTSD effects, however, the underlying mechanism of CBD remains inadequately investigated. Although many studies pertaining to PTSD have primarily focused on aberrations in neuronal functioning, the present study aimed to elucidate the involvement and functionality of microglia/macrophages in PTSD while also investigated the modulatory effects of CBD on neuroinflammation associated with this condition. We constructed a modified single-prolonged stress (SPS) mice PTSD model and verified the PTSD-related behaviors by various behavioral tests (contextual freezing test, elevated plus maze test, tail suspension test and novel object recognition test). We observed a significant upregulation of Iba-1 and alteration of microglial/macrophage morphology within the prefrontal cortex and hippocampus, but not the amygdala, two weeks after the PTSD-related stress, suggesting a persistent neuroinflammatory phenotype in the PTSD-modeled group. CBD (10 mg/kg, i.p.) inhibited all PTSD-related behaviors and reversed the alterations in both microglial/macrophage quantity and morphology when administered prior to behavioral assessments. We further found increased pro-inflammatory factors, decreased PSD95 expression, and impaired synaptic density in the hippocampus of the modeled group, all of which were also restored by CBD treatment. CBD dramatically increased the level of anandamide, one of the endocannabinoids, and cannabinoid type 2 receptors (CB2Rs) transcripts in the hippocampus compared with PTSD-modeled group. Importantly, we discovered the expression of CB2Rs mRNA in Arg-1-positive cells in vivo and found that the behavioral effects of CBD were diminished by CB2Rs antagonist AM630 (1 mg/kg, i.p.) and both the behavioral and molecular effects of CBD were abolished in CB2Rs knockout mice. These findings suggest that CBD would alleviate PTSD-like behaviors in mice by suppressing PTSD-related neuroinflammation and upregulation and activation of CB2Rs may serve as one of the underlying mechanisms for this therapeutic effect. The present study offers innovative experimental evidence supporting the utilization of CBD in PTSD treatment from the perspective of its regulation of neuroinflammation, and paves the way for leveraging the endocannabinoid system to regulate neuroinflammation as a potential therapeutic approach for psychiatric disorders.
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Encéfalo , Canabidiol , Modelos Animais de Doenças , Microglia , Doenças Neuroinflamatórias , Receptor CB2 de Canabinoide , Transtornos de Estresse Pós-Traumáticos , Animais , Canabidiol/farmacologia , Receptor CB2 de Canabinoide/metabolismo , Masculino , Camundongos , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/metabolismo , Microglia/efeitos dos fármacos , Microglia/metabolismo , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Endocanabinoides/metabolismo , Inflamação/metabolismo , Inflamação/tratamento farmacológico , Ácidos Araquidônicos/metabolismo , Ácidos Araquidônicos/farmacologiaRESUMO
The efficiency of foam drainage gas recovery is predominantly dictated by the performance of the foaming agent. To better understand their behavior, a novel testing apparatus was developed to simulate the foam drainage gas recovery process within the wellbore. Through the dynamic liquid-carrying performance tests of four foaming agents under uniform conditions, it was discerned that there existed significant disparities in the liquid-carrying performance and action duration. Further interface performance analysis disclosed that the liquid-carrying capacity and the duration were correlated with their adsorption capacity and interface activity at the gas-liquid interface. Notably, foaming agents with lower adsorption capacity and higher interfacial activity demonstrated superior liquid-carrying performance and longer action duration. By analyzing the consumption of foaming agents during the liquid-carrying process, five dynamic liquid-carrying equations were derived based on first-order reaction kinetics, the Malthusian population model, and the logistic function. The outcomes demonstrated that all these five equations could precisely delineate the dynamic liquid-carrying process of the foaming agent. During the research, we found that the consumption of the foaming agent in the foam drainage gas recovery process is related to its adsorption behavior at the gas-liquid interface, and revealed that the dynamic liquid-carrying process of foaming agent is the increasing process of liquid-carrying capacity under the continuous consumption of limited foaming agent resources. This laid a foundation for the further exploration of the functional mechanism of the foaming agent in the foam drainage gas recovery process.
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In American men, the incidence of prostate cancer (PC) is the highest among all types of cancer, making it the second leading cause of mortality associated with cancer. For advanced or metastatic PC, antiandrogen therapies are standard treatment options. The administration of these treatments unfortunately carries the potential risk of inducing neuroendocrine prostate cancer (NEPC). Neuroendocrine differentiation (NED) serves as a crucial indicator of prostate cancer development, encompassing various factors such as phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR), Yes-associated protein 1 (YAP1), AMP-activated protein kinase (AMPK), miRNA. The processes of autophagy and ferroptosis (an iron-dependent form of programmed cell death) play pivotal roles in the regulation of various types of cancers. Clinical trials and preclinical investigations have been conducted on many signaling pathways during the development of NEPC, with the deepening of research, autophagy and ferroptosis appear to be the potential target for regulating NEPC. Due to the dual nature of autophagy and ferroptosis in cancer, gaining a deeper understanding of the developmental programs associated with achieving autophagy and ferroptosis may enhance risk stratification and treatment efficacy for patients with NEPC.
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Autofagia , Ferroptose , Neoplasias da Próstata , Humanos , Ferroptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Masculino , Neoplasias da Próstata/patologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo , Animais , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/patologia , Tumores Neuroendócrinos/metabolismoRESUMO
Reactive oxygen species (ROS) play important roles in regulating various physiological functions in the human body, however, excessive ROS can cause serious damage to the human body, considering the various limitations of natural enzymes as scavengers of ROS in the body, the development of better materials for the scavenging of ROS is of great significance to the biomedical field, and nanozymes, as a kind of nanomaterials which can show the activity of natural enzymes. Have a good potential for the development in the area of ROS scavenging. Metal-organic frameworks (MOFs), which are porous crystalline materials with a periodic network structure composed of metal nodes and organic ligands, have been developed with a variety of active nanozymes including catalase-like, superoxide dismutase-like, and glutathione peroxidase-like enzymes due to the adjustability of active sites, structural diversity, excellent biocompatibility, and they have shown a wide range of applications and prospects. In the present review, we first introduce three representative natural enzymes for ROS scavenging in the human body, methods for the detection of relevant enzyme-like activities and mechanisms of enzyme-like clearance are discussed, meanwhile, we systematically summarize the progress of the research on MOF-based nanozymes, including the design strategy, mechanism of action, and medical application, etc. Finally, the current challenges of MOF-based nanozymes are summarized, and the future development direction is anticipated. We hope that this review can contribute to the research of MOF-based nanozymes in the medical field related to the scavenging of ROS.
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Estruturas Metalorgânicas , Espécies Reativas de Oxigênio , Estruturas Metalorgânicas/química , Espécies Reativas de Oxigênio/metabolismo , Humanos , Sequestradores de Radicais Livres/química , Nanoestruturas/química , Catalase/química , Catalase/metabolismo , Animais , Superóxido Dismutase/metabolismo , Superóxido Dismutase/químicaRESUMO
It is a promising research direction to develop catalysts with high stability and ozone utilization for low-temperature ozone catalytic oxidation of VOCs. While bimetallic catalysts exhibit excellent catalytic activity compared with conventional single noble metal catalysts, limited success has been achieved in the influence of the bimetallic effect on the stability and ozone utilization of metal catalysts. Herein, it is necessary to systematically study the enhancement effect in the ozone catalytic reaction induced by the second metal. With a simple continuous impregnation method, a platinum-cerium bimetallic catalyst is prepared. Also highlighted are studies from several aspects of the contribution of the second metal (Ce) to the stability and ozone utilization of the catalysts, including the "electronic effect" and "geometric effect". The synergistic removal rate of toluene and ozone is nearly 100% at 30 °C, and it still shows positive stability after high humidity and a long reaction time. More importantly, the instructive significance, which is the in-depth knowledge of enhanced catalytic mechanism of bimetallic catalysts resulting from a second metal, is provided by this work.
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Cério , Ozônio , Oxirredução , Metais , CatáliseRESUMO
Carbon/C3N heteronanotubes (CC3NNTs) have garnered significant interest for their distinctive performance and versatility across various applications. However, the understanding of interfacial heat transport within these heterostructures remains limited. This study aims to enrich the field by constructing models of CC3NNTs through the bonding of CNTs and C3NNTs, and employs nonequilibrium molecular dynamics (NEMD) simulations to predict their heat flux and thermal rectification (TR) effects. Placing the heat source in the CNT region induces a stronger heat flux compared to the C3NNT region, thus demonstrating a pronounced TR effect. This effect can be attributed to the mismatch in phonon spectra, as evidenced by the cumulative correlation factor derived from the phonon density of states (phonon DOS). Using this approach, we predict that the TR ratio for zigzag CC3NNTs (ZCC3NNT) significantly exceeds that of armchair CC3NNTs (ACC3NNT). Notably, in contrast to ACC3NNT, ZCC3NNT exhibits the phenomenon of negative differential thermal resistance in the backward heat flux with a temperature difference of Δ = 120 K. This phenomenon can be attributed to a lower phonon participation ratio at Δ = 120 K compared to other values of Δ. Subsequently, given that ZCC3NNT demonstrates the most pronounced TR ratio at room temperature, we explored how stress-strain, system size, defect density, and interface position impact the TR ratio. These insights are invaluable for guiding the design of thermal rectifiers, smart thermal management systems, and microelectronic processor coolers.
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Aim: Since use of major cutaneous surgeries/reconstructions among patients with cutaneous squamous cell carcinoma (CSCC) is not well described, we sought to quantify major cutaneous surgeries/reconstructions among patients with CSCC who were newly diagnosed and for those treated with systemic therapy, stratified by immune status. Methods: We used the Optum® Clinformatics® Data Mart database (2013-2020) and Kaplan-Meier estimators to assess risk of surgeries/reconstructions. Results: 450,803 patients were identified with an incident CSCC diagnosis, including 4111 patients with CSCC who initiated systemic therapy. The respective 7-year risks of major cutaneous surgeries/reconstructions were 10.9% (95% CI: 10.7-11.0) and 21.8% (95% CI: 17.6-25.8). Overall risk of major cutaneous surgeries/reconstructions was higher in patients who were immunocompromised than those who were immunocompetent. Conclusion: Approximately one in nine patients with CSCC will undergo ≥1 major cutaneous surgeries/reconstructions within 7 years of diagnosis; the risk increases in patients who initiate systemic therapy and among those who are immunocompromised.
Cutaneous squamous cell carcinoma (CSCC) is one of the two most common cancers, and numbers of new cases are increasing each year by 37%. A small number of advanced cases require systemic treatments (drugs given by mouth or injection), such as chemotherapy or immunotherapy. Patients with CSCC may require major skin surgeries and reconstructions. Little is known about how these skin procedures are used to treat patients with CSCC, particularly those with a weakened immune system. This analysis used USA insurance data of patients from 2013 to 2020 to assess how they were treated with surgeries, based on patients' immune status and whether they had started systemic treatment for CSCC. Among the 450,803 patients identified with a new CSCC diagnosis, the chances of having a procedure over a 7-year period was 10.9% (around one in nine). For 4111 patients with CSCC who started systemic therapy, this was 21.8% (around one in five). The chances of having a procedure were also significantly higher in patients with a weakened immune system (14.0%, around one in seven), compared with those without. However, this study was potentially limited by the following: the study population might not fully represent the CSCC population, the risk of surgery might be underestimated and information about patients' tumors (e.g., staging) was lacking. These results suggest there is an unmet need for systemic treatments that can reduce the burden of skin surgeries and reconstructions in CSCC.
Assuntos
Carcinoma de Células Escamosas , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Carcinoma de Células Escamosas/diagnóstico , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/diagnóstico , Estadiamento de Neoplasias , Pele/patologia , Procedimentos Cirúrgicos DermatológicosRESUMO
Background: Previous studies have mostly investigated the risk factors affecting the occurrence of leukoaraiosis and the risk factors affecting the severity of leukoaraiosis in patients with ischemic stroke, but there are relatively few studies on the risk factors and clinical characteristics affecting the severity of leukoaraiosis in the population with the most common type of first-episode ischemic stroke caused by intracranial atherosclerotic stenosis in China. Methods: We retrospectively studied patients with first-ever ischemic stroke due to intracranial atherosclerotic stenosis. All patients underwent diffusion weight magnetic resonance imaging and adjunctive examinations such as magnetic resonance angiography and/or computed tomography angiography and/or digital subtraction angiography. The characteristics and clinical data were also statistically analyzed. Results: Of the 504 patients enrolled, 176 (34.92%), 202 (40.08%), and 126 (25.00%) patients were in the mild, moderate, and severe groups, respectively, and the patients were older in the severe group compared with the moderate and mild groups (p < 0.05). Hypertension was more severe in the severe group compared with the severe and mild groups (p < 0.05). The time to hospital admission was shorter in the severe group compared with the moderate and mild groups (p < 0.05). The admission National Institutes of Health stroke scale was higher in the severe group than in the moderate and mild groups (p < 0.05). homocysteine, glucose, glycohemoglobin A1c, neutrophil-lymphocyte ratio, and ultrasensitive C-reactive protein to albumin ratio levels were significantly different between the three groups (p < 0.05). There was no significant correlation between the distribution of infarct foci in the anterior and posterior circulation in the three groups (p > 0.05). Conclusion: Age and homocysteine were independent risk factors for leukoaraiosis severity in patients with acute ischemic stroke, and all were positively associated with leukoaraiosis severity. Hypertension, glucose, glycohemoglobin A1c, neutrophil-lymphocyte ratio and ultrasensitive C-reactive protein to albumin ratio levels were highly significant in evaluating the prognosis of patients.
Assuntos
AVC Isquêmico , Leucoaraiose , Humanos , Leucoaraiose/diagnóstico por imagem , Leucoaraiose/complicações , Leucoaraiose/sangue , Feminino , Masculino , Pessoa de Meia-Idade , Fatores de Risco , AVC Isquêmico/sangue , AVC Isquêmico/complicações , AVC Isquêmico/diagnóstico por imagem , AVC Isquêmico/etiologia , AVC Isquêmico/diagnóstico , AVC Isquêmico/epidemiologia , Idoso , Estudos Retrospectivos , China/epidemiologia , Índice de Gravidade de Doença , Proteína C-Reativa/análise , Hipertensão/complicações , Angiografia por Ressonância Magnética , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/sangueRESUMO
Rationale: Over 40% of lung cancer cases occurred in never-smokers in China. However, high-risk never-smokers were precluded from benefiting from lung cancer screening as most screening guidelines did not consider them. Objectives: We sought to develop and validate prediction models for 3-year lung cancer risks for never- and ever-smokers, named the China National Cancer Center Lung Cancer models (China NCC-LCm2021 models). Methods: 425,626 never-smokers and 128,952 ever-smokers from the National Lung Cancer Screening program were used as the training cohort and analyzed using multivariable Cox models. Models were validated in two independent prospective cohorts: one included 369,650 never-smokers and 107,678 ever-smokers (841 and 421 lung cancers), and the other included 286,327 never-smokers and 78,469 ever-smokers (503 and 127 lung cancers). Measurements and Main Results: The areas under the receiver operating characteristic curves in the two validation cohorts were 0.698 and 0.673 for never-smokers and 0.728 and 0.752 for ever-smokers. Our models had higher areas under the receiver operating characteristic curves than other existing models and were well calibrated in the validation cohort. The China NCC-LCm2021 ⩾0.47% threshold was suggested for never-smokers and ⩾0.51% for ever-smokers. Moreover, we provided a range of threshold options with corresponding expected screening outcomes, screening targets, and screening efficiency. Conclusion: The construction of the China NCC-LCm2021 models can accurately reflect individual risk of lung cancer, regardless of smoking status. Our models can significantly increase the feasibility of conducting centralized lung cancer screening programs because we provide justified thresholds to define the high-risk population of lung cancer and threshold options to adapt different configurations of medical resources.