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Background: Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening medical condition with a high fatality and morbidity rate. There was a substantial link between the modified Fisher grade of aSAH and the neurological function deficit. This study aimed to analyze the factors associated with the modified Fisher grade of aSAH using a machine learning approach. Methods: A multi-center observational study was conducted. The patients with aSAH were recruited from five tertiary hospitals in China. The volume of hemorrhage in aSAH was measured using the modified Fisher grade scale. The risk factors responsible for the modified Fisher grade of aSAH were analyzed, which include sociodemographic factors, clinical factors, blood index, and ruptured aneurysm characteristics. We built several tree-based machine learning models (XGBoost, CatBoost, LightGBM) for prediction and used grid search to optimize model parameters. To comprehensively evaluate the model, we used Accuracy, Precision, Area Under the Receiver Operating Characteristic Curve (AUROC), Area Under the Precision-Recall Curve (AUPRC), and Brier as evaluation indicators to assess the model performance and select the best model. Results: A total of 888 patients with aSAH were recruited, of whom 305 with modified Fisher grade of 3 and 4. The results show that the XGBoost model has the highest AUROC of 0.772, and the indicators are better than CatBoost and LightGBM. The feature importance graph shows that the top feature variables include platelet, thrombin time, fibrinogen, preadmission systolic blood pressure, activated partial thromboplastin time, and the time interval between the onset of aSAH and the first-time CT examination. Conclusion: The factors responsible for the modified Fisher grade of aSAH were identified, which offered valuable insights for future research and clinical intervention. These risk factors should be controlled in the treatment of unruptured aneurysms, and appropriate treatment can be given if necessary to reduce the risk of severe hemorrhage after aneurysm rupture.
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Generation of mammalian red blood cells requires the expulsion of polarized nuclei late in terminal erythroid differentiation. However, the mechanisms by which spherical erythroblasts determine the direction of nuclear polarization and maintain asymmetry during nuclear expulsion are poorly understood. Given the analogy of erythroblast enucleation to asymmetric cell division and the key role of Aurora kinases in mitosis, we sought to investigate the function of Aurora kinases in erythroblast enucleation. We found that AURKA (Aurora kinase A) is abundantly expressed in orthochromatic erythroblasts. Intriguingly, high-resolution confocal microscopy analyses revealed that AURKA co-localized with the centrosome on the side of the nucleus opposite its membrane contact point during polarization and subsequently translocated to the anterior end of the protrusive nucleus upon nuclear exit. Mechanistically, AURKA regulated centrosome maturation and localization via interaction with i-tubulin to provide polarization orientation for the nucleus. Furthermore, we identified ECT2 (epithelial cell transforming 2), a guanine nucleotide exchange factor, as a new interacting protein and ubiquitination substrate of AURKA. After forming the nuclear protrusion, AURKA translocated to the anterior end of the protrusive nucleus to directly degrade ECT2, which is partly dependent on kinase activity of AURKA. Moreover, knockdown of ECT2 rescued impaired enucleation caused by AURKA inhibition. Our findings have uncovered a previously unrecognized role of Aurora kinases in the establishment of nuclear polarization and eventual nuclear extrusion and provide new mechanistic insights into erythroblast enucleation.
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PURPOSE: This study aimed to evaluate changes in ultrafast pulse wave velocity (ufPWV) in individuals with arterial stiffness and subclinical atherosclerosis (subAS), and to provide cutoff values. METHODS: This retrospective study recruited 231 participants, including 67 patients with subAS. The pulse wave velocity was measured at the beginning and end of systole (PWV-BS and PWVES, respectively) using ultrafast ultrasonography to assess arterial stiffness. The right and left common carotid arteries were measured separately, and laboratory metabolic parameters were also collected. Participants were balanced between groups using propensity score matching (PSM) at a 1:1 ratio, adjusting for age, sex, and waist-to-hip ratio as potential confounders. Cutoff values of ufPWV for monitoring subAS were determined via receiver operating characteristic (ROC) curve analysis. RESULTS: PWV-ES, unlike PWV-BS, was higher in the subAS subgroup than in the subAS-free group after PSM (all P<0.05). For each 1 m/s increase in left, right, and bilateral mean PWV-ES, the risk of subAS increased by 23% (95% confidence interval [CI], 1.04 to 1.46), 26% (95% CI, 1.07 to 1.52), and 38% (95% CI, 1.12 to 1.72), respectively. According to ROC analyses, predictive potential was found for left PWV-ES (cutoff value=7.910 m/s, P=0.002), right PWV-ES (cutoff value=6.615 m/s, P=0.003), and bilateral mean PWV-ES (cutoff value=7.415 m/s, P<0.001), but not for PWV-BS (all P>0.05). CONCLUSION: PWV-ES measured using ultrafast ultrasonography was significantly higher in individuals with subAS than in those without. Specific PWV-ES cutoff values showed potential for predicting an increased risk of subAS.
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Background: As the overall survival (OS) of patients with multiple myeloma (MM) improves, the incidence of second primary malignancy (SPM) in long-term complications increases. However, there are limited data regarding MM as a SPM. Therefore, this study aimed to determine the time trends in the incidence of MM, as well as the incidence and survival of patients with MM as the SPM. Methods: Kaplan-Meier survival analysis was performed to determine the survival curve, while a log-rank test was used to determine OS. Results: A total of 794 patients were diagnosed with MM among 7,921 patients with hematologic malignancy between 2009 and 2017. The incidence of MM showed an annual upward trend, increasing from 9.3% [2009-2011] to 10.8% [2015-2017]. Of the 794 patients with MM, 16 were diagnosed as the SPM commonly secondary to cancers of the lung (n=4), colon (n=3), breast (n=3), and other (n=6). The median survival of patients with MM as the SPM was 24.5 months (range, 1-95 months). The patients with MM without multiple malignancies had significantly longer survival (median, 46.5 months; range, 17-132 months; P=0.04). Conclusions: This retrospective study suggests that the incidence of MM may be increasing annually and that the survival of patients with MM as the second primary malignant was significantly shorter than that of those without multiple malignancies.
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This paper initially examines the feasibility and effectiveness on interfacial adhesion of composites when grafting nanoparticle-structured polydopamine (PDA) and chitosan around carbon fiber periphery. The resulting interfacial shear strength was maximized as 92.3 MPa, delivering 50.1 % and 15.7-16.2 % gains over those of control fiber and only polydopamine nanospheres (PDANPs) or only chitosan modified fiber composites. Measuring surface morphology and thermal stability of fibers found that abundant PDANPs well adhered with the help of chitosan, highlighting nanoscale size effects and intrinsic adhesiveness of PDA. Under good wettability, rich and dense interfacial interactions (covalent and hydrogen bond, electrostatic interaction, and π conjugation) caused by PDANPs/chitosan coating provides impetus for effective stress transfer. Additionally, the stable "soft-rigid" combination of chitosan and PDANPs adds the efficiency of crack passivation. As such, it is hoped that this work could fully explore the possibility of PDA geometry in interphase engineering of fiber composites.
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Fibra de Carbono , Quitosana , Indóis , Nanosferas , Polímeros , Quitosana/química , Indóis/química , Nanosferas/química , Polímeros/química , Fibra de Carbono/química , MolhabilidadeRESUMO
Phloroglucinol (1,3,5-trihydroxybenzene) is a key intermediate in the degradation of polyphenols such as flavonoids and hydrolysable tannins and can be used by certain bacteria as a carbon and energy source for growth. The identification of enzymes that participate in the fermentation of phloroglucinol to acetate and butyrate in Clostridia was recently reported. In this study, we present the discovery and characterization of a novel metabolic pathway for phloroglucinol degradation in the bacterium Collinsella sp. zg1085, from marmot respiratory tract. In both the Clostridial and Collinsella pathways, phloroglucinol is first reduced to dihydrophoroglucinol by the NADPH-dependent phloroglucinol reductase (PGR), followed by ring opening to form (S)-3-hydroxy-5-oxohexanoate by a Mn2+-dependent dihydrophloroglucinol cyclohydrolase (DPGC). In the Collinsella pathway, (S)-3-hydroxy-5-oxohexanoate is then cleaved to form malonate semialdehyde and acetone by a newly identified aldolase (HOHA). Finally, a NADP+-dependent malonate-semialdehyde dehydrogenase converts malonate semialdehyde to CO2 and acetyl-CoA, an intermediate in carbon and energy metabolism. Recombinant expression of the Collinsella PGR, DPGC, and HOHA in E. coli enabled the conversion of phloroglucinol into acetone, providing support for the proposed pathway. Experiments with Olsenella profusa, another bacterium containing the gene cluster of interest, show that the PGR, DPGC, HOHA, and MSDH are induced by phloroglucinol. Our findings add to the variety of metabolic pathways for the degradation of phloroglucinol, a widely distributed phenolic compound, in the anaerobic microbiome.IMPORTANCEPhloroglucinol is an important intermediate in the bacterial degradation of polyphenols, a highly abundant class of plant natural products. Recent research has identified key enzymes of the phloroglucinol degradation pathway in butyrate-producing anaerobic bacteria, which involves cleavage of a linear triketide intermediate by a beta ketoacid cleavage enzyme, requiring acetyl-CoA as a co-substrate. This paper reports a variant of the pathway in the lactic acid bacterium Collinsella sp. zg1085, which involves cleavage of the triketide intermediate by a homolog of deoxyribose-5-phosphate aldolase, highlighting the variety of mechanisms for phloroglucinol degradation by different anaerobic bacterial taxa.
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Redes e Vias Metabólicas , Floroglucinol , Floroglucinol/metabolismo , Floroglucinol/análogos & derivados , Redes e Vias Metabólicas/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Aldeído Liases/metabolismo , Aldeído Liases/genética , AnimaisRESUMO
Experimental studies have shown that vitamin C has anti-cancer effects, but previous meta-analyses have indicated that the role of vitamin C in digestive system cancers (DSCs) is controversial. In this study, a systematic review and meta-analysis of the relationship between dietary intake/plasma concentration of vitamin C and the risk of DSC was conducted, evaluating 32 prospective studies with 1 664 498 participants. Dose-response and subgroup analyses were also performed. Systematic literature searches were performed in PubMed, EMBASE and Web of Science databases until 9th September 2023. Vitamin C intake significantly reduced DSCs risk (RR = 0.88, 95% confidence interval (CI) 0.83 to 0.93). The subgroup analyses showed the risks of oral, pharyngeal, and esophageal (OPE) cancers (0.81, 0.72 to 0.93), gastric cancer (0.81, 0.68 to 0.95), and colorectal cancer (0.89, 0.82 to 0.98) were negatively correlated with vitamin C intake, and the effect of vitamin C was different between colon cancer (0.87, 0.77 to 0.97) and rectal cancer (1.00, 0.84 to 1.19). However, plasma vitamin C concentration was only inversely associated with gastric cancer risk (0.74, 0.59 to 0.92). Dose-response analysis revealed that 250 and 65 mg day-1 vitamin C intakes had the strongest protective effect against OPE and gastric cancers respectively. These estimates suggest that vitamin C intake could significantly reduce gastrointestinal cancer incidence, including OPE, gastric, and colon cancers. Plasma vitamin C has a significant reduction effect on the incidence of gastric cancer only, but additional large-scale clinical studies are needed to determine its impact on the incidence of DSCs.
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Ácido Ascórbico , Neoplasias do Sistema Digestório , Humanos , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Neoplasias do Sistema Digestório/sangue , Neoplasias do Sistema Digestório/prevenção & controle , Neoplasias do Sistema Digestório/epidemiologia , Estudos Prospectivos , Dieta , Fatores de Risco , Masculino , FemininoRESUMO
Maturation of postnatal ß cells is regulated in a cell-autonomous manner, and metabolically stressed ß cells regress to an immature state, ensuring defective ß-cell function and the onset of type 2 diabetes. The molecular mechanisms connecting the nutritional transition to ß-cell maturation remain largely unknown. Here, we report a miR-203/ZBTB20/MAFA regulatory axis that mediates the ß-cell maturation process. We show that miR-203 level in ß cells changes during the nutritional transition and that miR-203 inhibits ß-cell maturation at the neonatal stage and under high-fat diet (HFD) conditions. Using single-cell RNA sequencing, we demonstrated that miR-203 elevation promoted the transition of immature ß cells into CgBHi endocrine cells, while suppressing gene expressions associated with ß-cell maturation in a ZBTB20/MAFA-dependent manner. ZBTB20 is an authentic target of miR-203 and transcriptionally upregulates MAFA expression. Manipulating the miR-203/ZBTB20/MAFA axis may therefore offer a novel strategy for boosting functional ß-cell numbers to alleviate diabetes.
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BACKGROUND: Aging-related type 2 diabetes (T2DM) is characterized by hyperinsulinemia, insulin resistance, and ß-cell dysfunction. However, the underlying molecular mechanisms remain to be unclear. METHODS: We conducted non-targeted metabolomics to compare human serum samples from young adults (YA), elderly adults (EA), and elderly adults with diabetes (EA + DM) of Chinese population. Adult mice and aged mice were intragastrically administered with varespladib every day for two weeks and metabolic characteristics were monitored. Serum levels of arachidonic acid, insulin, and C-peptide, as well as serum activity of secretory phospholipase A2 (sPLA2) were detected in mice. Mouse islet perfusion assays were used to assess insulin secretion ability. Phosphorylated AKT levels were measured to evaluate insulin sensitivities of peripheral tissues in mice. RESULTS: Non-targeted metabolomics analysis of human serum samples revealed differential metabolic signatures among the YA, EA, and EA + DM groups. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed significant enhancement of arachidonic acid metabolism and glycerophospholipid metabolism in the EA group compared with the YA group. Further analysis identified two metabolic fluxes that favored the accumulation of arachidonic acid in the elderly. Increased levels of arachidonic acid were also confirmed in aged mice with hyperinsulinemia and insulin resistance, together with subsequent glucose intolerance. Conversely, inhibiting the generation of arachidonic acid with varespladib, an inhibitor of sPLA2, reduced aging-associated diabetes by improving hyperinsulinemia and hepatic insulin resistance in aged mice but not in adult mice. Islet perfusion assays also showed that varespladib treatment suppressed the enhanced insulin secretion observed in aged islets. CONCLUSIONS: Collectively, our findings uncover that arachidonic acid serves as a metabolic hub in Chinese elderly population. Our results also suggest that arachidonic acid plays a fundamental role in regulating ß-cell function during aging and point to a novel therapy for aging-associated diabetes.
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Envelhecimento , Ácido Araquidônico , Hiperinsulinismo , Resistência à Insulina , Animais , Ácido Araquidônico/metabolismo , Ácido Araquidônico/sangue , Humanos , Camundongos , Masculino , Idoso , Diabetes Mellitus Tipo 2/metabolismo , Adulto , Camundongos Endogâmicos C57BL , Feminino , Adulto Jovem , Metabolômica , Insulina/sangue , Insulina/metabolismo , Pessoa de Meia-IdadeRESUMO
Tetanus toxin (TeNT) is one of the most toxic proteins. Neutralizing antibodies against TeNT are effective in prevention and treatment. In this study, 14 anti-tetanus nanobodies were obtained from a phage display nanobody library by immunizing a camel with the C-terminal receptor-binding domain of TeNT (TeNT-Hc) as the antigen. After fusion with the human Fc fragment, 11 chimeric heavy-chain antibodies demonstrated nanomolar binding toward TeNT-Hc. The results of toxin neutralization experiments showed that T83-7, T83-8, and T83-13 completely protected mice against 20 × the median lethal dose (LD50) at a low concentration. The neutralizing potency of T83-7, T83-8, and T83-13 against TeNT is 0.4 IU/mg, 0.4 IU/mg and 0.2 IU/mg, respectively. In the prophylactic setting, we found that 5 mg/kg of T83-13 provided the mice with full protection from tetanus, even when they were injected 14 days before exposure to 20 × LD50 TeNT. T83-7 and T83-8 were less effective, being fully protective only when challenged 7 or 10 days before exposure, respectively. In the therapeutic setting, 12 h after exposure to TeNT, 1 ~ 5 mg/kg of T83-7, and T83-8 could provide complete protection for mice against 5 × LD50 TeNT, while 1 mg/kg T83-13 could provide complete protection 24 h after exposure to 5 × LD50 TeNT. Our results suggested that these antibodies represent prophylactic and therapeutic activities against TeNT in a mouse model. The T83-7, T83-8, and T83-13 could form the basis for the subsequent development of drugs to treat TeNT toxicity.
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Anticorpos Neutralizantes , Cadeias Pesadas de Imunoglobulinas , Anticorpos de Domínio Único , Toxina Tetânica , Tétano , Animais , Toxina Tetânica/imunologia , Tétano/prevenção & controle , Tétano/imunologia , Anticorpos Neutralizantes/imunologia , Camundongos , Anticorpos de Domínio Único/imunologia , Cadeias Pesadas de Imunoglobulinas/imunologia , Feminino , Camelus/imunologia , Humanos , Anticorpos Antibacterianos/imunologia , Camundongos Endogâmicos BALB CRESUMO
To mitigate the continued impact of SARS-CoV-2, influenza A, and influenza B viruses on human health, a smartphone-based point-of-care testing (POCT) system was designed to detect respiratory pathogens through a nucleic acid test. This compact, light-weight, highly automated, and universal system enables the differential diagnosis of SARS-CoV-2, influenza A, and influenza B in approximately 30 min in a single-tube reaction. Numerous hospitals and disease control and prevention center assessed the triple POCT system's detection threshold, sensitivity, specificity, and stability, and have concluded that all the assessments were comparable to those of fluorescent quantitative polymerase chain reaction (PCR)-based testing. The triple POCT system is suitable as an onsite rapid-diagnosis device, as well as for pathogen screening at airports and customs.
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A new compound, named coniferin B (1), and fourteen known compounds were purified and identified from the leaves and branches of Wikstroemia chamaedaphne Meisn. Their chemical structures were elucidated through analyzing spectroscopic and HRESIMS data. Compounds 2, 3, 5, 7-9, 11, and 13 were isolated from this plant for the first time. All compounds were assayed for cytotoxicity and activation of latent HIV activity on NH2 cells. The results showed that all compounds did not produce cytotoxicity at 10.0 µM and compounds 1, 9-11 showed weak activating activity with activation folds of 4.88, 7.14, 5.3, and 6.97, respectively.
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This study aimed to explore the effects of neonatal vitamin A (VA) supplementation on testis development and spermatogenesis. A total of 32 newborn lambs were intramuscularly injected with corn oil (control group) or corn oil + 2500 IU/kg BW VA (VA group). They were slaughtered and sampled at 3 weeks and 8 months of age to analyze spermatogenesis, cell proliferation, hormone secretion, antioxidant status of the testis, and adult sheep sperm parameters. Compared with the control group, the expression of spermatogonial differentiation-related genes in VA group was up-regulated (P < 0.05). Testis weight, seminiferous tubule diameter, number of spermatogonium and spermatocyte, and sperm density increased significantly in VA group at 8 months of age (P < 0.05). Neonatal VA injection upregulated the expression of the cell proliferation marker PCNA and cell cycle-related genes in the testis (P < 0.05). VA increased the concentrations of testosterone (T), luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in the serum and upregulated steroidogenesis-related genes in the testis (P < 0.05). The antioxidant levels in the VA group were maintained at high levels. The total antioxidant capacity (T-AOC), antioxidant enzyme content and antioxidant-related genes were increased in the testis (P < 0.05). Furthermore, neonatal VA injection activated retinoic acid (RA) signaling to maintain the blood-testosterone barrier (BTB) in the testis of 3-week-old sheep. AMP-activated protein kinase (AMPK) and protein kinase B (AKT) signaling were also modulated in the sheep testis (P < 0.05). Taken together, VA supplementation in newborn rams promotes testis development and spermatogenesis to improve fertility.
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Chronic myeloid leukemia (CML) is a type of hematologic malignancies caused by BCR-ABL chimeric oncogene. Resistance to tyrosine kinase inhibitors (TKIs) leads to the progression of CML into advanced stages. Selinexor is a small molecule inhibitor that targets a nuclear transporter called Exportin 1. Combined with imatinib, selinexor has been shown to disrupt nuclear-cytoplasmic transport signal of leukemia stem cells, resulting in cell death. The objective of this study was to investigate the mechanism of drug resistance to selinexor in CML. We established K562 cell line resistant to selinexor and conducted single cell dynamic transcriptome sequencing to analyze the heterogeneity within the parental and selinexor resistant cell populations. We identified specific gene expression changes associated with resistance to selinexor. Our results revealed differential expression patterns in genes such as MT2A, TFPI, MTND3, and HMGCS1 in the total RNA, as well as MT-TW, DNAJB1, and HSPB1 in the newly synthesized RNA, between the parental and drug-resistant groups. By applying pseudo-time analysis, we discovered that a specific cluster of cells exhibited characteristics of tumor stem cells. Furthermore, we observed a gradual decrease in the expression of ferroptosis-related molecules as drug resistance developed. In vitro experiments confirmed that the combination of a ferroptosis inducer called RSL3 effectively overcame drug resistance. In conclusion, this study revealed the resistance mechanism of selinexor in CML. In conclusion, we identified a subgroup of CML cells with tumor stem cell properties and demonstrated that ferroptosis inducer improved the efficacy of selinexor in overcoming drug resistance.
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Resistencia a Medicamentos Antineoplásicos , Hidrazinas , Leucemia Mielogênica Crônica BCR-ABL Positiva , Triazóis , Humanos , Hidrazinas/farmacologia , Hidrazinas/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Resistencia a Medicamentos Antineoplásicos/genética , Triazóis/farmacologia , Células K562 , Análise de Célula Única , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , RNA-Seq , Análise da Expressão Gênica de Célula ÚnicaRESUMO
Background: Quantitative detection of glucose-6-phosphate dehydrogenase (G6PD) is commonly done to screen for G6PD deficiency. However, current reference intervals (RIs) of G6PD are unsuitable for evaluating G6PD-activity levels with local populations or associating G6PD variants with hemolysis risk to aid clinical decision-making. We explored appropriate RIs and clinical decision limits (CDLs) for G6PD activity in individuals from Guangzhou, China. Methods: We enrolled 5,852 unrelated individuals between 2020 and 2022 and screened their samples in quantitative assays for G6PD activity. We conducted further investigations, including G6PD genotyping, thalassemia genotyping, follow-up analysis, and statistical analysis, for different groups. Results: In Guangzhou, the RIs for the G6PD activities were 11.20-20.04 U/g Hb in male and 12.29-23.16 U/g Hb in female. The adjusted male median and normal male median (NMM) values were 15.47 U/g Hb and 15.51 U/g Hb, respectively. A threshold of 45% of the NMM could be used as a CDL to estimate the probability of G6PD variants. Our results revealed high hemolysis-risk CDLs (male: <10% of the NMM, female: <30% of the NMM), medium hemolysis-risk CDLs (male: 10%-45% of the NMM, female: 30%-79% of the NMM), and low hemolysis-risk CDLs (male: ≥ 45% of the NMM, female: ≥ 79% of the NMM). Conclusions: Collectively, our findings contribute to a more accurate evaluation of G6PD-activity levels within the local population and provide valuable insights for clinical decision-making. Specifically, identifying threshold values for G6PD variants and hemolysis risk enables improved prediction and management of G6PD deficiency, ultimately enhancing patient care and treatment outcomes.
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G protein pathway suppressor 2 (GPS2) has been shown to play a pivotal role in human and mouse definitive erythropoiesis in an EKLF-dependent manner. However, whether GPS2 affects human primitive erythropoiesis is still unknown. This study demonstrated that GPS2 positively regulates erythroid differentiation in K562 cells, which have a primitive erythroid phenotype. Overexpression of GPS2 promoted hemin-induced hemoglobin synthesis in K562 cells as assessed by the increased percentage of benzidine-positive cells and the deeper red coloration of the cell pellets. In contrast, knockdown of GPS2 inhibited hemin-induced erythroid differentiation of K562 cells. GPS2 overexpression also enhanced erythroid differentiation of K562 cells induced by cytosine arabinoside (Ara-C). GPS2 induced hemoglobin synthesis by increasing the expression of globin and ALAS2 genes, either under steady state or upon hemin treatment. Promotion of erythroid differentiation of K562 cells by GPS2 mainly relies on NCOR1, as knockdown of NCOR1 or lack of the NCOR1-binding domain of GPS2 potently diminished the promotive effect. Thus, our study revealed a previously unknown role of GPS2 in regulating human primitive erythropoiesis in K562 cells.
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Diferenciação Celular , Eritropoese , Hemina , Leucemia Eritroblástica Aguda , Correpressor 1 de Receptor Nuclear , Humanos , Células K562 , Eritropoese/genética , Leucemia Eritroblástica Aguda/patologia , Leucemia Eritroblástica Aguda/metabolismo , Leucemia Eritroblástica Aguda/genética , Correpressor 1 de Receptor Nuclear/metabolismo , Correpressor 1 de Receptor Nuclear/genética , Hemina/farmacologia , Células Eritroides/metabolismo , Células Eritroides/citologia , 5-Aminolevulinato Sintetase/genética , 5-Aminolevulinato Sintetase/metabolismo , Hemoglobinas/metabolismo , Técnicas de Silenciamento de Genes , Peptídeos e Proteínas de Sinalização IntracelularRESUMO
Background: Botulinum neurotoxin (BoNT) produced by Clostridium botulinum is one of the most potent known toxins. Moreover, BoNT is classified as one of the most important biological warfare agents that threatens the biosafety of the world. Currently, the approved treatment for botulism in humans is the use of polyvalent horse serum antitoxins. However, they are greatly limited because of insufficient supply and adverse reactions. Thus, treatment of human botulism requires the development of effective toxin-neutralizing antibodies. Considering their advantages, neutralizing nanobodies will play an increasing role as BoNTs therapeutics. Methods: Herein, neutralizing nanobodies binding to the heavy chain (Hc) domain of BoNT/B (BHc) were screened from a phage display library. Then, BoNT/B-specific clones were identified and fused with the human Fc fragment (hFc) to form chimeric heavy chain antibodies. Finally, the affinity, specificity, and neutralizing activity of antibodies against BoNT/B in vivo were evaluated. Results: The B5-hFc, B9-hFc and B12-hFc antibodies demonstrated high affinity for BHc in the nanomolar range. The three antibodies were proven to have potent neutralizing activity against BoNT/B in vivo. Conclusion: The results demonstrate that inhibiting toxin binding to the host receptor is an efficient strategy and the three antibodies could be used as candidates for the further development of drugs to prevent and treat botulism.
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Anticorpos Neutralizantes , Toxinas Botulínicas Tipo A , Botulismo , Animais , Feminino , Humanos , Camundongos , Anticorpos Antibacterianos/imunologia , Anticorpos Neutralizantes/imunologia , Afinidade de Anticorpos , Toxinas Botulínicas Tipo A/imunologia , Botulismo/imunologia , Botulismo/terapia , Cadeias Pesadas de Imunoglobulinas/imunologia , Biblioteca de Peptídeos , Anticorpos de Domínio Único/imunologiaRESUMO
Chronic inflammation is critical for the initiation and progression of type 2 diabetes mellitus via causing both insulin resistance and pancreatic ß cell dysfunction. miR-155, highly expressed in macrophages, is a master regulator of chronic inflammation. Here we show that blocking a macrophage-derived exosomal miR-155 (MDE-miR-155) mitigates the insulin resistances and glucose intolerances in high-fat-diet (HFD) feeding and type-2 diabetic db/db mice. Lentivirus-based miR-155 sponge decreases the level of miR-155 in the pancreas and improves glucose-stimulated insulin secretion (GSIS) ability of ß cells, thus leading to improvements of insulin sensitivities in the liver and adipose tissues. Mechanistically, miR-155 increases its expression in HFD and db/db islets and is released as exosomes by islet-resident macrophages under metabolic stressed conditions. MDE-miR-155 enters ß cells and causes defects in GSIS function and insulin biosynthesis via the miR-155-PDX1 axis. Our findings offer a treatment strategy for inflammation-associated diabetes via targeting miR-155.
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Breast cancer has the highest global incidence and mortality rates among all cancer types. Abnormal expression of the Annexin family has been observed in different malignant tumors, including upregulated ANXA9 in breast cancer. We found highly expressed ANXA9 in metastatic breast cancer tissues, which is correlated with breast cancer progression. In vitro, the functional experiments indicated ANXA9 influenced breast cancer proliferation, motility, invasion, and apoptosis; in vivo, downregulation of ANXA9 suppressed breast cancer xenograft tumor growth and lung metastasis. Mechanically, on one side, we found that ANXA9 could mediate S100A4 and therefore regulate AKT/mTOR/STAT3 pathway to participate p53/Bcl-2 apoptosis; on the other side, we found ANXA9 transferred S100A4 from cells into the tumor microenvironment and mediated the excretion of cytokines IL-6, IL-8, CCL2, and CCL5 to participate angiogenesis via self- phosphorylation at site Ser2 and site Thr69. Our findings demonstrate significant involvement of ANXA9 in promoting breast cancer progression, thereby suggesting that therapeutic intervention via targeting ANXA9 may be effective in treating metastatic breast cancer.
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Neoplasias da Mama , Neoplasias Pulmonares , Humanos , Feminino , Neoplasias da Mama/genética , Mama , Fosforilação , Regulação para Baixo , Microambiente Tumoral , Proteína A4 de Ligação a Cálcio da Família S100 , Anexinas , Fator de Transcrição STAT3RESUMO
In vitro cell culture serves as an efficient system for studying animal cell behavior in a controlled setting. Here, we present a 3D culture model for forming ruminant adipose organoids using stromal vascular fraction cells. We describe steps for forming cell spheroids and growing them on a Matrigel-coated surface. We then detail procedures for inducing organoids to undergo angiogenesis and adipogenesis followed by capillary sprouting. This protocol can be utilized to study the interaction between blood vessels and adipocytes. For complete details on the use and execution of this protocol, please refer to Yu et al.1.