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Macrostructural control of stress distribution and microstructural influence on crack propagation is one of the strategies for obtaining high mechanical properties in stag beetle upper jaws. The maximum bending fracture force of the stag beetle upper jaw is approximately 154, 000 times the weight of the upper jaw. Here, we explore the macro and micro-structural characteristics of two stag beetle upper jaws and reveal the resulting differences in mechanical properties and enhancement mechanisms. At the macroscopic level, the elliptic and triangular cross-sections of the upper jaw of the two species of stag beetles have significant effects on the formation of cracks. The crack generated by the upper jaws with a triangular section grows slowly and deflects easily. At the microscopic level, the upper jaw of the two species is a chitin cross-layered structure, but the difference between the two adjacent fiber layers at 45° and 50° leads to different deflection paths of the cracks on the exoskeleton. The mechanical properties of the upper jaw of the two species of stag beetle were significantly different due to the interaction of macro-structure and micro-structure. In addition, a series of bionic samples with different cross-section geometries and different fiber cross angles were designed, and mechanical tests were carried out according to the macro-structure and micro-structure characteristics of the stag beetle upper jaw. The effects of cross-section geometry and fiber cross angle on the mechanical properties of bionic samples are compared and analyzed. This study provides new ideas for designing and optimizing highly loaded components in engineering. STATEMENT OF SIGNIFICANCE: The upper jaw of the stag beetle is composed of a complex arrangement of chitin and protein fibers, providing both rigidity and flexibility. This structure is designed to withstand various mechanical stresses, including impacts and bending forces, encountered during its burrowing activities and interactions with its environment. The study of the upper jaw of the stag beetle can provide an efficient structural design for engineering components that are subjected to high loads. Understanding the relationship between structure and mechanical properties in the stag beetle upper jaw holds significant implications for biomimetic design and engineering.
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Dysregulation of renal tubular epithelial cell (RTEC) apoptosis is one of the critical steps underlying the occurrence and development of nephrolithiasis. Although N6-methyladenosine (m6A) modification has been extensively studied and associated with various pathologic processes, research on its specific role in RTEC injury and apoptosis remains limited. In this study, we found that overexpression of ALKBH5 reduced the level of m6A modification in RTEC cells and notably promoted RTEC apoptosis. Further mechanism studies revealed that ALKBH5 mainly decreased the m6A level on the mRNA of Mucin 1 (MUC1) gene in RTECs. Moreover, ALKBH5 impaired the stability of MUC1 mRNA in RTECs, leading to attenuated expression of MUC1. Finally, we determined that the ALKBH5-MUC1 axis primarily facilitated RTEC apoptosis by regulating the PI3K/Akt signaling pathway. This study revealed the critical role of the ALKBH5-MUC1-PI3K/Akt regulatory system in RTEC apoptosis and provided new therapeutic targets for treating nephrolithiasis.
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OBJECTIVE: To evaluate the effectiveness of home-based cardiac telerehabilitation based on wearable electrocardiogram or heart rate monitoring devices in patients with heart disease. METHODS: We searched eight electronic databases under the guidance of Cochrane Handbook and PRISMA recommendations. RESULTS: The meta-analysis included data from 14 articles (15 RCTs) representing 1314 participants. A significant improvement in left ventricular ejection fraction [MD = 2.12, 95 % CI (1.21, 3.04), P < 0.001], 6-minute walk distance [MD = 40.00, 95 % CI (21.72, 58.29), P < 0.001] and peak oxygen intake [MD = 2.24, 95 % CI (1.38, 3.10), P < 0.001] were observed in the home-based cardiac telerehabilitation group. But it had no difference in anxiety [SMD = -0.83, 95 % CI (-1.65, -0.02), P = 0.05] and depression [SMD = -0.59, 95 % CI (-1.26, 0.09), P = 0.09]. Subgroup analyses revealed that interventions of no less than 3 months improved anxiety [SMD = -1.11, 95 % CI (-2.05, -0.18), P = 0.02] and depression [SMD = -1.01, 95 % CI (-1.93, -0.08), P = 0.03]. CONCLUSION: Home-based cardiac telerehabilitation based on wearable electrocardiogram or heart rate monitoring devices has a positive effect on cardiac function. Long-term (≥ 3 months) cardiac rehabilitation might benefit individuals suffering from anxiety or depression.
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Electrocardiografía , Cardiopatías , Frecuencia Cardíaca , Ensayos Clínicos Controlados Aleatorios como Asunto , Telerrehabilitación , Dispositivos Electrónicos Vestibles , Humanos , Frecuencia Cardíaca/fisiología , Cardiopatías/rehabilitación , Servicios de Atención de Salud a Domicilio , Rehabilitación Cardiaca/métodos , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodosRESUMEN
The rapid mutation of SARS-CoV-2 has led to multiple rounds of large-scale breakthrough infection and reinfection worldwide. However, the dynamic changes of humoral and cellular immunity responses to several subvariants after infection remain unclear. In our study, a 6-month longitudinal immune response evaluation was conducted on 118 sera and 50 PBMC samples from 49 healthy individuals who experienced BA.5/BF.7/XBB breakthrough infection or BA.5/BF.7-XBB reinfection. By studying antibody response, memory B cell, and IFN-γ secreting CD4+/CD8+ T cell response to several SARS-CoV-2 variants, we observed that each component of immune response exhibited distinct kinetics. Either BA.5/BF.7/XBB breakthrough infection or BA.5/BF.7-XBB reinfection induces relatively high level of binding and neutralizing antibody titers against Omicron subvariants at an early time point, which rapidly decreases over time. Most of the individuals at 6 months post-breakthrough infection completely lost their neutralizing activities against BQ.1.1, CH.1.1, BA.2.86, JN.1 and XBB subvariants. Individuals with BA.5/BF.7-XBB reinfection exhibit immune imprinting shifting and recall pre-existing BA.5/BF.7 neutralization antibodies. In the BA.5 breakthrough infection group, the frequency of BA.5 and XBB.1.16-RBD specific memory B cells, resting memory B cells, and intermediate memory B cells gradually increased over time. On the other hand, the frequency of IFN-γ secreting CD4+/CD8+ T cells induced by WT/BA.5/XBB.1.16 spike trimer remains stable over time. Overall, our research indicates that individuals with breakthrough infection have rapidly declining antibody levels but have a relatively stable cellular immunity that can provide some degree of protection from future exposure to new antigens.
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Actinomycosis is a chronic granulomatous disease that can affect various parts of the body, including the head and neck, lungs, abdominal and pelvic cavities, and wounds. It is caused by different actinomycetes like Actinomyces sherdii, Actinomyces glasii, Actinomyces cariosa, Actinomyces zurichensis, and Actinomyces europaea. Reported infections caused by actinomycetes include pulmonary actinomycosis, pelvic and abdominal infections, bone or artificial joint infections, endocarditis, complicated urinary tract infections, and soft tissue abscesses. The combination of pulmonary actinomycosis with gastric cancer is exceptionally rare in clinical practice, and the presence of actinomycetal infection alongside tumors in elderly patients poses significant challenges in treatment. This article presents the diagnosis and treatment process of an elderly patient with pulmonary actinomycosis and gastric adenocarcinoma.
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The multi-level structure is a strategy to enhance the mechanical properties of dung beetle leg joints. Under external loads, the microstructure facilitates energy dissipation and prevents crack extension. The macrostructure aids in transferring the load to more reliable parts. The connection established by the two hemispheres is present in the dung beetle leg joint. The micron-layered and nanoscale crystal structures further constitute the leg joint with excellent mechanical properties. The maximum compression fracture force is ≈101000 times the weight of the leg. Here, the structural design within the dung beetle leg joints and reveal the resulting mechanical response and enhancement mechanisms is determined. A series of beetle leg joints where the macrostructure and microstructure of the dung beetle leg provide mechanical strength at critical strains while avoiding catastrophic failure by transferring the load from the joint to the exoskeleton of the femur is highlighted. Nanocrystalline structures and fiber layers contribute to crack propagation of the exoskeleton. Based on this, the bionic joint with multi-level structures using resin and conducted a series of tests to verify their effectiveness is prepared. This study provides a new idea for designing and optimizing high-load joints in engineering.
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Escarabajos , Animales , Escarabajos/fisiología , Fenómenos Biomecánicos , Articulaciones/fisiología , Estrés MecánicoRESUMEN
Background: Erectile dysfunction (ED) is a common condition affecting middle-aged and elderly men. Aim: The study sought to investigate differentially expressed fatty acid metabolism-related genes and the molecular mechanisms of ED. Methods: The expression profiles of GSE2457 and GSE31247 were downloaded from the Gene Expression Omnibus database and merged. Differentially expressed genes (DEGs) between ED and normal samples were obtained using the R package limma. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses of DEGs were conducted using the R package clusterProfiler. Fatty acid metabolism-related DEGs (FAMDEGs) were further identified and analyzed. Machine learning algorithms, including Lasso (least absolute shrinkage and selection operator), support vector machine, and random forest algorithms, were utilized to identify hub FAMDEGs with the ability to predict ED occurrence. Coexpression analysis and gene set enrichment analysis of hub FAMDEGs were performed. Outcome: Fatty acid metabolism-related functions (such as fatty acid metabolism and degradation) may play a vital role in ED. Results: In total, 5 hub FAMDEGs (Aldh2, Eci2, Acat1, Acadl, and Hadha) were identified and found to be differentially expressed between ED and normal samples. Gene set enrichment analysis identified key pathways associated with these genes. The area under the curve values of the 5 hub FAMDEGs for predicting ED occurrence were all >0.8. Clinical Translation: Our results suggest that these 5 key FAMDEGs may serve as biomarkers for the diagnosis and treatment of ED. Strengths and Limitations: The strengths of our study include the use of multiple datasets and machine learning algorithms to identify key FAMDEGs. However, limitations include the lack of validation in animal models and human tissues, as well as research on the mechanisms of these FAMDEGs. Conclusion: Five hub FAMDEGs were identified as potential biomarkers for ED progression. Our work may prove that fatty acid metabolism-related genes are worth further investigation in ED.
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Lymphocytes play crucial roles in the human immune system; however, detailed metabolite characteristics need to be further investigated. Herein, we propose a lymphocyte classification method based on metabolite profiling at the single-cell level. The percentages of different lymphocyte types were calculated with a low margin of error, confirming that the metabolites could serve as a basis for lymphocyte classification. Furthermore, we analyzed the CD4/CD8 ratio in human peripheral blood to verify the feasibility of this method for the classification of lymphocyte subtypes. The proposed method is expected to be a potential tool for the clinical diagnosis of lymphocyte-related diseases.
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Linfocitos T CD8-positivos , Linfocitos , Humanos , Linfocitos T CD8-positivos/metabolismo , Linfocitos T CD4-Positivos/metabolismoRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: Taohong Siwu decoction (TSD) is a classic traditional Chinese medicine (TCM) prescription used to promote the blood circulation and alleviate blood stasis. TSD consists of Paeonia lactiflora Pall., Conioselinum anthriscoides (H. Boissieu) Pimenov & Kljuykov, Rehmannia glutinosa (Gaertn.) DC., Prunus persica (L.) Batsch, Angelica sinensis (Oliv.) Diels, and Carthamus creticus L. in the ratio of 3:2:4:3:3:2. Studies on the effects of TSD on myocardial ischemia-reperfusion injury (MIRI) from the perspective of autophagy and pyroptosis have not been reported. AIM OF THE STUDY: Investigate the effect of TSD on MIRI and explore the underlying mechanisms. MATERIALS AND METHODS: We searched the main components and corresponding potential targets of TSD on The Pharmacology of Traditional Chinese Medicine Systems database for target prediction. We identified targets for MIRI on Online Mendelian Inheritance in Man and GeneCards databases. The intersection of the compound target and disease target was obtained and a protein-protein interaction network constructed. We undertook enrichment analyses using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes databases. The results of network pharmacology were verified by in vivo experiments in mice. RESULTS: In mice, TSD significantly reduced the volume of the myocardial infarct, significantly reduced serum levels of cardiac troponin-nI (CTnI), creatine kinase-myocardial band (CK-MB), malonaldehyde (MDA), interleukin (IL)-6, increased the activity of superoxide dismutase (SOD) and IL-10 level, reduced the level of pyroptosis in myocardial tissue, increased the number of autophagosomes, and significantly reduced the fluorescence intensity of apoptosis-associated speck-like protein (ASC), Nod-like receptor protein 3 (NLRP3), and caspase-1. TSD administration increased the protein expression of microtubule-associated protein light chain 3 (LC3), but reduced the protein expression of p62, NLRP3, ASC, caspase-1, cleaved caspase-1, pro-caspase-1, gasdermin D (GSDMD), GSDMD-N-terminal, IL-18, and IL-1ß. Administration of 3-Methyladenin could reverse the effect of TSD in inhibiting inflammation and the release of proinflammatory factors. CONCLUSION: TSD treatment alleviated MIRI by promoting autophagy to suppress activation of the NLRP3 inflammasome and reducing the release of proinflammatory factors.
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Daño por Reperfusión Miocárdica , Humanos , Ratones , Animales , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Piroptosis , Inflamasomas/metabolismo , Autofagia , Interleucina-6 , CaspasasRESUMEN
Emerging SARS-CoV-2 sub-lineages like XBB.1.5, XBB.1.16, EG.5, HK.3 (FLip), and XBB.2.3 and the variant BA.2.86 have recently been identified. Understanding the efficacy of current vaccines on these emerging variants is critical. We evaluate the serum neutralization activities of participants who received COVID-19 inactivated vaccine (CoronaVac), those who received the recently approved tetravalent protein vaccine (SCTV01E), or those who had contracted a breakthrough infection with BA.5/BF.7/XBB virus. Neutralization profiles against a broad panel of 30 sub-lineages reveal that BQ.1.1, CH.1.1, and all the XBB sub-lineages exhibit heightened resistance to neutralization compared to previous variants. However, despite their extra mutations, BA.2.86 and the emerging XBB sub-lineages do not demonstrate significantly increased resistance to neutralization over XBB.1.5. Encouragingly, the SCTV01E booster consistently induces higher neutralizing titers against all these variants than breakthrough infection does. Cellular immunity assays also show that the SCTV01E booster elicits a higher frequency of virus-specific memory B cells. Our findings support the development of multivalent vaccines to combat future variants.
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Infección Irruptiva , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , Humanos , COVID-19/prevención & control , SARS-CoV-2/genética , Anticuerpos Neutralizantes , Anticuerpos AntiviralesRESUMEN
The motion process of legged robots contains not only rigid-body motion but also flexible motion with elastic deformation of the legs, especially for heavy loads. Hence, the characteristics of the flexible components and their interactions with the rigid components need to be considered. In this paper, a hierarchical control strategy for robots with rigid-flexible coupling characteristics is proposed. This strategy involves (1) leg force prediction based on real-time motion trajectories and feedforward compensation for the error caused by flexible components; (2) building upon the centroid dynamics model of the rigid-body chassis, the centroid trajectories (centroid angular momentum (CAM) and centroid linear momentum (CLM)) and the body trajectory are taken into account to derive the optimal drive torque for maintaining body stability; (3) finally, the precise force control of the hydraulic drive units is achieved through the sliding mode control algorithm, integrating the dynamic model of the flexible legs. The proposed methods are validated on a giant hexapod robot weighing 3.5 tons, demonstrating that the introduced approach can reduce the robot's vibrations.
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IMPORTANCE: Vaccinia virus infection requires virus-cell membrane fusion to complete entry during endocytosis; however, it contains a large viral fusion protein complex of 11 viral proteins that share no structure or sequence homology to all the known viral fusion proteins, including type I, II, and III fusion proteins. It is thus very challenging to investigate how the vaccinia fusion complex works to trigger membrane fusion with host cells. In this study, we crystallized the ectodomain of vaccinia H2 protein, one component of the viral fusion complex. Furthermore, we performed a series of mutational, biochemical, and molecular analyses and identified two surface loops containing 170LGYSG174 and 125RRGTGDAW132 as the A28-binding region. We also showed that residues in the N-terminal helical region (amino acids 51-90) are also important for H2 function.
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Fusión de Membrana , Virus Vaccinia , Proteínas Virales de Fusión , Internalización del Virus , Virus Vaccinia/química , Virus Vaccinia/genética , Virus Vaccinia/metabolismo , Proteínas Virales de Fusión/química , Proteínas Virales de Fusión/genética , Proteínas Virales de Fusión/metabolismoRESUMEN
Introduction: The impact of severe hydronephrosis on the outcomes of minimally invasive percutaneous nephrolithotomy (MPCNL) remains controversial; it is still a subject well worth exploration. Aim: To investigate the effects of severe hydronephrosis on surgical outcomes of MPCNL, especially on operative time (OT) and stone-free rate (SFR). Material and methods: In total, 301 patients who underwent MPCNL were included in this study and divided into 4 groups according to the degree of hydronephrosis (nil, mild, moderate, and severe hydronephrosis, respectively). Univariate analyses and multivariate logistic analyses were used to determine the risk factors affecting OT and SFR. Results: Patients with severe hydronephrosis had a longer OT (p < 0.001), a decreased SFR (p < 0.001), and a higher postoperative haemoglobin drop and blood transfusion rate compared to the other 3 cohorts (p = 0.011 and p = 0.043, respectively). Univariate analyses determined that severe hydronephrosis, calyx for access, stone location, stone type, stone size, and number of tracts significantly correlated with OT, while severe hydronephrosis, stone location, stone type, and stone size showed a strong association with SFR (all p < 0.05). Multivariate analyses further identified that severe hydronephrosis (OR = 3.496, p = 0.013), stone location (≥ 4 calyces: OR = 3.024, p = 0.017), stone type (staghorn: OR = 5.204, p = 0.002), and stone size (≥ 1600 mm2: OR = 12.669, p < 0.001; 800-1599 mm2: OR = 5.194, p < 0.001) were significant risk factors affecting OT, while SFR was independently influenced by stone type (staghorn: OR = 4.377, p = 0.039; multiple: OR = 3.778, p = 0.044), stone location (≥ 4 calyces: OR = 4.413, p = 0.020; 2-3 calyces: OR = 3.617, p = 0.034), and severe hydronephrosis (OR = 7.093, p = 0.001). Conclusions: Severe hydronephrosis is a significant risk factor that can lead to longer OT and lower SFR, and correlates with increased risk of bleeding and blood transfusion rate in some cases during MPCNL. Accordingly, severe hydronephrosis is an influential factor that should not be ignored when performing MPCNL.
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Background: Tafolecimab is a novel fully human proprotein convertase subtilisin/kexin type 9 (PCSK9) monoclonal antibody, developed for the treatment of hypercholesterolemia. Objectives: The purpose of this study was to assess the efficacy and safety of tafolecimab in Chinese patients at high or very high cardiovascular risk with hypercholesterolemia. Methods: Patients with diagnoses of heterozygous familial hypercholesterolemia (HeFH) by the Simon Broome criteria or at high or very high cardiovascular risk with nonfamilial hypercholesterolemia, with screening low-density lipoprotein cholesterol (LDL-C) level ≥1.8 mmol/L, were randomized 2:1 to receive tafolecimab or placebo 450 mg every 4 weeks (Q4W) in the 12-week double-blind treatment period. The primary endpoint was the percent change from baseline to week 12 in LDL-C levels. Results: A total of 303 patients were enrolled and received at least 1 dose of tafolecimab (n = 205) or placebo (n = 98). The least squares mean percent change in LDL-C level from baseline to week 12 was -68.9% (SE 1.4%) in the tafolecimab group and -5.8% (1.8%) in the placebo group (difference: -63.0%; [95% CI: -66.5% to -59.6%]; P < 0.0001). More patients treated with tafolecimab achieved ≥50% LDL-C reductions, LDL-C <1.8 mmol/L, and LDL-C <1.4 mmol/L at week 12 than did those in the placebo group (all P < 0.0001). Furthermore, tafolecimab markedly reduced non-HDL-C, apolipoprotein B, and lipoprotein(a) levels. During the double-blind treatment period, the most commonly reported adverse events included urinary tract infection (5.9% with tafolecimab vs 4.1% with placebo) and hyperuricemia (3.4% vs 4.1%). Conclusions: Tafolecimab was safe and showed robust lipid-lowering efficacy in Chinese patients at high or very high cardiovascular risk with hypercholesterolemia. (A Study of IBI306 in Participants With Hypercholesterolemia; NCT04709536).
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The difference in power demand and the driver's operation in various operation stages make the loader have the problem of low energy utilization. Changeable operating objects and drastically changing loads have exacerbated the difficulty of energy-saving research in different operating stages of loaders. Therefore, based on identifying the operation stage and analyzing the load characteristics under typical working conditions of the loader, this paper proposes a shovel-loading cooperative control strategy. Specifically, the Drag Reduction Insertion (DRI) in the shoveling stage is realized based on learning the driving intention. Based on different operation stages, the load characteristics of different materials for shovel-loading are deeply analyzed, and the prediction research of the power output characteristics of the power unit is carried out. The shovel-loading cooperative control solves the problem of the poor economy caused by different power requirements in different operation stages and significantly reduces the impact of the driver's operating experience.
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Hydrogel adhesives are extensively employed in biological interfaces such as epidermal flexible electronics, tissue engineering, and implanted device. The development of functional hydrogel adhesives is a critical, yet challenging task since combining two or more attributes that seem incompatible into one adhesive hydrogel without sacrificing the hydrogel's pristine capabilities. In this Review, we highlight current developments in the fabrication of functional adhesive hydrogels, which are suitable for a variety of application scenarios, particularly those that occur underwater or on tissue/organ surface conditions. The design strategies for a multifunctional adhesive hydrogel with desirable properties including underwater adhesion, self-healing, good biocompatibility, electrical conductivity, and anti-swelling are discussed comprehensively. We then discuss the challenges faced by adhesive hydrogels, as well as their potential applications in biological interfaces. Adhesive hydrogels are the star building blocks of bio-interface materials for individualized healthcare and other bioengineering areas.
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Objective To summarize the clinical features of spontaneous remission in classic fever of unknown origin (FUO). Methods Medical records of 121 patients diagnosed with FUO at admission in Peking Union Medical College Hospital between January 2018 and June 2018 were reviewed retrospectively. Patients who were discharged without etiological diagnoses were followed for 2 years. The clinical features and outcomes of these patients were summarized. Multivariate logistic regression was used to analyze related factors of spontaneous remission of FUO. Results After excluding 2 patients who lost to follow-up, the etiology of 119 FUO patients were as follows: infectious diseases in 30 (25.2%) cases, connective tissue diseases in 28 (23.5%) cases, tumor diseases in 8 (6.7%) cases, other diseases in 6 (5.0%) cases, and unknown diagnoses in 47 (39.5%) cases. Totally, 41 patients experienced spontaneous remission of fever (the median time from onset to remission was 9 weeks, ranging from 4 to 39 weeks). In patients with spontaneous remission in FUO, lymphadenopathy was less common clinical manifestation, the levels of inflammatory markers including leukocyte count, neutrophil count, neutrophil ratio, C-reactive protein, and ferritin were lower, and the proportion of CD8 positive T lymphocytes expressing CD38 was lower. Multivariate logistic regression analysis of factors with a P-value < 0.05 in univariate analysis shown that white blood cell count (OR: 0.545, 95%CI: 0.306-0.971, P = 0.039), neutrophil count (OR: 2.074, 95%CI: 1.004-4.284, P = 0.049), and proportion of neutrophils (OR: 0.928, 95%CI: 0.871-0.990, P = 0.022) were independent significant factors associated with spontaneous remission in FUO. Conclusions This study suggested that most patients discharged with undiagnosed classic FUO would remit spontaneously. Thus, for patients with stable clinical conditions, follow-up and observation could be the best choice. Patients with lower level of some inflammatory factors may have a high likelihood of spontaneous remission in classic FUO.
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Enfermedades Transmisibles , Fiebre de Origen Desconocido , Enfermedades Transmisibles/complicaciones , Fiebre de Origen Desconocido/complicaciones , Fiebre de Origen Desconocido/diagnóstico , Hospitalización , Humanos , Remisión Espontánea , Estudios RetrospectivosRESUMEN
Oxidative DNA damage contributes to aging and the pathogenesis of numerous human diseases including cancer. 8-hydroxyguanine (8-oxoG) is the major product of oxidative DNA lesions. Although OGG1-mediated base excision repair is the primary mechanism for 8-oxoG removal, DNA mismatch repair has also been implicated in processing oxidative DNA damage. However, the mechanism of the latter is not fully understood. Here, we treated human cells defective in various 8-oxoG repair factors with H2O2 and performed biochemical, live cell imaging, and chromatin immunoprecipitation sequencing analyses to determine their response to the treatment. We show that the mismatch repair processing of oxidative DNA damage involves cohesive interactions between mismatch recognition protein MutSα, histone mark H3K36me3, and H3K36 trimethyltransferase SETD2, which activates the ATM DNA damage signaling pathway. We found that cells depleted of MutSα or SETD2 accumulate 8-oxoG adducts and fail to trigger H2O2-induced ATM activation. Furthermore, we show that SETD2 physically interacts with both MutSα and ATM, which suggests a role for SETD2 in transducing DNA damage signals from lesion-bound MutSα to ATM. Consistently, MutSα and SETD2 are highly coenriched at oxidative damage sites. The data presented here support a model wherein MutSα, SETD2, ATM, and H3K36me3 constitute a positive feedback loop to help cells cope with oxidative DNA damage.
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Reparación de la Incompatibilidad de ADN , N-Metiltransferasa de Histona-Lisina , Proteínas MutS , Estrés Oxidativo , Daño del ADN , Código de Histonas , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Histonas/genética , Humanos , Peróxido de Hidrógeno/farmacología , Proteínas MutS/genética , Proteínas MutS/metabolismoRESUMEN
Introduction: Intracranial atherosclerotic disease (ICAD) is one of the most important etiologies of ischemic stroke, especially in Asia. Although medical treatment was recommended as the first-line therapy for ICAD, the recurrent stroke rate was still high in severe stenosis of ICAD despite aggressive medical treatment. Traditionally, the degree of luminal stenosis is used as the principal index for stroke risk stratification in patients with ICAD, while recent evidence suggested that symptomatic atherosclerotic plaques were characterized by plaque features and hemodynamics. This prospective, longitudinal, and nested case-control study aims to identify multimodal imaging predictors of high-risk patients with ICAD refractory to medical treatment and explore a refined risk stratification model based on the above multimodal imaging predictors. Methods: This prospective, longitudinal, and nested case-control study includes 400 symptomatic patients with ICAD with 50-99% of stenosis treated with aggressive medical therapy. All patients who meet the eligibility criteria are assessed by multimodal imaging examination from three aspects, including lumen stenosis, plaque characteristics, and hemodynamic features. The enrolled patients receive aggressive medical management, including antiplatelet therapy and cardiovascular risk control. The primary outcome is ischemic stroke or death attributable to the lesion of the target vessel within 1 year. The secondary endpoints are (1) any stroke or death; (2) all-cause mortality; (3) any stroke out of the territory of the responsible lesion; (4) functional outcome with the modified Rankin Scale (mRS). Ethics and Dissemination: This study has been approved by the ethics committee of our center ([2021]083) and has been prospectively registered (Registration No: ChiCTR2100048832). Study findings will be disseminated through peer-reviewed publications and presentations at scientific meetings.