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The function and homeostasis of the mammalian ovary depend on complex paracrine interactions between multiple cell types. Using primary mouse tissues and isolated cells, we showed in vitro that ovarian follicles secrete a factor(s) that suppresses growth of ovarian epithelial cells in culture. Most of the growth suppressive activity was accounted for by Anti-Mullerian Hormone/Mullerian Inhibitory Substance (AMH/MIS) secreted by granulosa cells of the follicles, as determined by immune depletion experiments. Additionally, conditioned medium from granulosa cells from wild type control, but not AMH knockout, suppressed epithelial cell growth. Tracing of the AMH regulated cells using AMHR2 (AMH receptor 2)-Cre:ROSA26 mutant mice indicated the presence of populations of AMHR2-positive epithelial cells on the ovarian surface and oviduct epithelia. Cells isolated from the mutant mice indicated that a subpopulation of cells marked by AMHR2-Cre:ROSA26 accounted for most cell growth and expansion in ovarian surface epithelial cells, and the AMHR2 lineage derived cells were regulated by AMH in vitro; whereas, fewer AMHR2-Cre:ROSA26 marked cells accounted for oviduct epithelial cell outgrowth. The results reveal a paracrine pathway in maintaining follicle-epithelial homeostasis in ovary and support a subpopulation of AMHR2 lineage marked epithelial cells as ovarian epithelial stem/progenitor cells with higher proliferative potential regulatable by follicle secreted AMH.
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Extrachromosomal circular DNA (eccDNA) is a closed-circle, nuclear, nonplasmid DNA molecule found in all tested eukaryotes. eccDNA plays important roles in cancer pathogenesis, evolution of tumor heterogeneity, and therapeutic resistance. It is known under many names, including very large cancer-specific circular extrachromosomal DNA (ecDNA), which carries oncogenes and is often amplified in cancer cells. Our understanding of eccDNA has historically been limited and fragmented. To provide better a context of new and previous research on eccDNA, in this review we give an overview of the various names given to eccDNA at different times. We describe the different mechanisms for formation of eccDNA and the methods used to study eccDNA thus far. Finally, we explore the potential clinical value of eccDNA.
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ADN Circular , Neoplasias , ADN/genética , ADN Circular/genética , Humanos , Neoplasias/genéticaRESUMEN
AIMS: To investigate the molecular events associated with acquiring macrolide resistance genes [mefE/mel (Mega) or ermB] in Streptococcus pneumoniae (Spn) during nasopharyngeal colonization. METHODS AND RESULTS: Genomic analysis of 128 macrolide-resistant Spn isolates revealed recombination events in genes of the conjugation apparatus, or the competence system, in strains carrying Tn916-related elements. Studies using confocal and electron microscopy demonstrated that during the transfer of Tn916-related elements in nasopharyngeal cell biofilms, pneumococcal strains formed clusters facilitating their acquisition of resistance determinants at a high recombination frequency (rF). Remarkably, these aggregates comprise both encapsulated and nonencapsulated pneumococci that span extracellular and intracellular compartments. rF assessments showed similar rates regardless Mega was associated with large integrative and conjugative elements (ICEs) (>23â¯kb) or not (â¼5.4â¯kb). The rF for Mega Class IV(c) insertion region (â¼53â¯kb) was three orders of magnitude higher than the transformation of the capsule locus. Metabolomics studies of the microenvironment created by colonization of human nasopharyngeal cells revealed a link between the acquisition of ICEs and the pathways involving nicotinic acid and sucrose. CONCLUSIONS: Pneumococcal clusters, both extracellular and intracellular, facilitate macrolide resistance acquisition, and ICEs were acquired at a higher frequency than the capsule locus. Metabolic changes could serve as intervention targets.
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A concise enantioselective total synthesis of (-)-daphenylline, a hexacyclic Daphniphyllum alkaloid with a unique benzene ring, was achieved in 14 steps. The synthesis commences with two chiral stereocenters, C2 and C18, readily installed via Carreira's Ir/amine dual-catalyzed allylation. The allylic bridgehead amine 6 was rapidly prepared through Wickens' photoredox-catalyzed hydrocarboxylation of olefin and CuBr2-catalyzed α-amination of ketone. The tetracycle 4 was formed via Pd-catalyzed reductive Heck reaction or, more concisely, by Krische's Rh-catalyzed reductive 1,6-enyne cyclization. In this synthesis, newly reported Wickens' photoredox-catalyzed hydrocarboxylation was used twice, and Friedel-Crafts acylation thrice.
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Large reserves, high capacity, and low cost are the core competitiveness of disordered carbon materials as excellent anode materials for sodium-ion batteries (SIBs). And the existence and improper treatment of a large number of organic solid wastes will aggravate the burden on the environment, therefore, it is significant to transform wastes into carbon-based materials for sustainable energy utilization. Herein, a kind of hard carbon materials are reported with waste biomass-foam as the precursor, which can improve the sodium storage performance through pre-oxidation strategy. The introduction of oxygen-containing groups can promote structural cross-linking, and inhibit the melting and rearrangement of carbon structure during high-temperature carbonization that produces a disordered structure with a suitable degree of graphitization. Moreover, the micropore structure are also regulated during the high-temperature carbonization process, which is conducive to the storage of sodium ions in the low-voltage plateau region. The optimized sample as an electrode material exhibits excellent reversible specific capacity (308.0 mAh g-1) and initial Coulombic efficiency (ICE, 90.1%). In addition, a full cell with the waste foam-derived hard carbon anode and a Na3V2(PO4)3 cathode is constructed with high ICE and energy density. This work provides an effective strategy to conversion the waste to high-value hard carbon anode for sodium-ion batteries.
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BACKGROUND: Colorectal cancer (CRC) commonly exhibits tolerance to cisplatin treatment, but the underlying mechanisms remain unclear. Within the tumor microenvironment, macrophages play a role in resisting the cytotoxic effects of chemotherapy by engaging in efferocytosis to clear apoptotic cells induced by chemotherapeutic agents. The involvement of extracellular vesicles (EVs), an intercellular communicator within the tumor microenvironment, in regulating the efferocytosis for the promotion of drug resistance has not been thoroughly investigated. METHODS: We constructed GFP fluorescent-expressing CRC cell lines (including GFP-CT26 and GFP-MC38) to detect macrophage efferocytosis through flow cytometric analysis. We isolated and purified CRC-secreted EVs using a multi-step ultracentrifugation method and identified them through electron microscopy and nanoflow cytometry. Proteomic analysis was conducted to identify the protein molecules carried by CRC-EVs. MFGE8 knockout CRC cell lines were constructed using CRISPR-Cas9, and their effects were validated through in vitro and in vivo experiments using Western blotting, immunofluorescence, and flow cytometric analysis, confirming that these EVs activate the macrophage αvß3-Src-FAK-STAT3 signaling pathway, thereby promoting efferocytosis. RESULTS: In this study, we found that CRC-derived EVs (CRC-EVs) enhanced macrophage efferocytosis of cisplatin-induced apoptotic CRC cells. Analysis of The Cancer Genome Atlas (TCGA) database revealed a high expression of the efferocytosis-associated gene MFGE8 in CRC patients, suggesting a poorer prognosis. Additionally, mass spectrometry-based proteomic analysis identified a high abundance of MFGE8 protein in CRC-EVs. Utilizing CRISPR-Cas9 gene edition system, we generated MFGE8-knockout CRC cells, demonstrating that their EVs fail to upregulate macrophage efferocytosis in vitro and in vivo. Furthermore, we demonstrated that MFGE8 in CRC-EVs stimulated macrophage efferocytosis by increasing the expression of αvß3 on the cell surface, thereby activating the intracellular Src-FAK-STAT3 signaling pathway. CONCLUSIONS: Therefore, this study highlighted a mechanism in CRC-EVs carrying MFGE8 activated the macrophage efferocytosis. This activation promoted the clearance of cisplatin-induced apoptotic CRC cells, contributing to CRC resistance against cisplatin. These findings provide novel insights into the potential synergistic application of chemotherapy drugs, EVs inhibitors, and efferocytosis antagonists for CRC treatment.
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Neoplasias Colorrectales , Vesículas Extracelulares , Macrófagos , Fagocitosis , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/genética , Macrófagos/metabolismo , Humanos , Animales , Línea Celular Tumoral , Ratones , Factor de Transcripción STAT3/metabolismo , Factor de Transcripción STAT3/genética , Transducción de Señal , Cisplatino/farmacología , Integrina alfaVbeta3/metabolismo , Integrina alfaVbeta3/genética , EferocitosisRESUMEN
Proteus mirabilis is a commensal bacterium dwelling in the gastrointestinal (GI) tract of humans and animals. Although New Delhi metallo-ß-lactamase 1 (NDM-1) producing P. mirabilis is emerging as a threat, its epidemiology in our society remains largely unknown. LHPm1, the first P. mirabilis isolate harboring NDM-1, was detected from a companion dog that resides with a human owner. The whole-genome study revealed 20 different antimicrobial resistance (AMR) genes against various classes of antimicrobial agents, which corresponded to the MIC results. Genomic regions, including MDR genes, were identified with multiple variations and visualized in a comparative manner. In the whole-genome epidemiological analysis, multiple phylogroups were identified, revealing the genetic relationship of LHPm1 with other P. mirabilis strains carrying various AMR genes. These genetic findings offer comprehensive insights into NDM-1-producing P. mirabilis, underscoring the need for urgent control measures and surveillance programs using a "one health approach".
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Enfermedades de los Perros , Infecciones por Proteus , Perros , Humanos , Animales , Antibacterianos/farmacología , Proteus mirabilis/genética , Mascotas/genética , Infecciones por Proteus/veterinaria , Infecciones por Proteus/microbiología , Farmacorresistencia Bacteriana Múltiple/genética , Genómica , República de Corea , Pruebas de Sensibilidad Microbiana/veterinaria , Plásmidos , Enfermedades de los Perros/genéticaRESUMEN
OPINION STATEMENT: Gastrointestinal stromal tumor (GIST) is characterized by well-defined oncogenes. Despite the significant improvement in treatment outcomes with adjuvant imatinib therapy for patients, drug resistance remains a major challenge for GIST therapy. This review focuses on the mechanisms contributing to drug resistance phenotype in GIST, such as primary imatinib-resistant mutants, secondary mutations, non-covalent binding of TKI to its target, tumor heterogeneity, re-activation of pro-survival/proliferation pathways through non-KIT/PDGFRA kinases, and loss of therapeutic targets in wild-type GIST. Corresponding suggestions are proposed to overcome drug-resistance phenotype of GIST. This review also summarizes the suitability of currently approved TKIs on different KIT/PDGFRA mutations and updates related clinical trials. Recent potent drugs and emerging strategies against advanced GISTs in clinical trials are presented. Additionally, metabolic intervention offers a new avenue for clinical management in GIST. A landscape of metabolism in GIST and metabolic changes under imatinib treatment are summarized based on currently published data. The OXPHOS pathway is a promising therapeutic target in combination with TKI against sensitive KIT/PDGFRA mutants. Comprehensive understanding of the above resistance mechanisms, experimental drugs/strategies and metabolic changes is critical to implement the proper therapy strategy and improve the clinical therapy outcomes for GIST.
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Resistencia a Antineoplásicos , Tumores del Estroma Gastrointestinal , Mutación , Inhibidores de Proteínas Quinasas , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Humanos , Inhibidores de Proteínas Quinasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacología , Proteínas Proto-Oncogénicas c-kit/genética , Proteínas Proto-Oncogénicas c-kit/metabolismo , Neoplasias Gastrointestinales/tratamiento farmacológico , Terapia Molecular Dirigida , Manejo de la Enfermedad , Resultado del Tratamiento , Mesilato de Imatinib/uso terapéutico , Biomarcadores de Tumor , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/genética , Receptor alfa de Factor de Crecimiento Derivado de Plaquetas/metabolismoRESUMEN
In recent years, we have realized that extracellular vesicles (EVs) play a critical role in regulating the intercellular communication between tumor and immune cells in the tumor microenvironment (TME). Tumor-derived extracellular vesicles (TDEVs) profoundly affect the functional changes of tumor-associated macrophages (TAMs) and promote their M2 polarization. Meanwhile, macrophages have a strong phagocytic ability in phagocytosing apoptotic cells. Especially in the course of chemotherapy or radiotherapy, TAMs can phagocytose and remove apoptotic tumor cells, showing anti-inflammatory and pro-tumor effects. However, the underlying mechanisms by which TDEVs regulate macrophage phagocytosis of apoptotic tumor cells have not been fully elucidated. In this study, we focused on the effect of colorectal cancer-derived extracellular vesicles (CRC-EVs) on macrophages. We demonstrated that CRC-EVs enhanced macrophage phagocytosis of apoptotic CRC cells. We then determined that heat shock protein 70 (HSP70) carried in CRC-EVs was responsible for this effect by using mass spectrometry-based proteomic analysis and the CRISPR-Cas9 system. Through transcriptome sequencing of macrophages, we found that the enhanced phagocytosis of macrophages was mainly due to the up-regulation of the macrophage receptor with collagenous structure (MARCO). In addition, we confirmed that the up-regulation of MARCO was mediated by the AKT-STAT3 signaling pathway. Taken together, this study revealed a novel EVs-mediated macrophage phagocytosis mechanism involved in the clearance of apoptotic tumor cells in the TME. Targeting TDEVs may have potential therapeutic applications in tumor treatment.
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Neoplasias Colorrectales , Vesículas Extracelulares , Humanos , Proteínas HSP70 de Choque Térmico/genética , Proteínas HSP70 de Choque Térmico/metabolismo , Proteómica , Macrófagos/metabolismo , Fagocitosis , Vesículas Extracelulares/metabolismo , Neoplasias Colorrectales/metabolismo , Microambiente TumoralRESUMEN
Extrachromosomal circular DNAs (eccDNAs) carrying random genomic segments are broadly found across different cancer types, but their molecular functions and impact in gastric cancer (GC) are rarely known. In this study, we aimed to investigate the potential role of eccDNA in GC. Using the Circle-seq strategy, we observed the eccDNA abundance in gastric cancer tissues (GCT) was aberrantly higher than that of normal adjacent tissues (NAT). The high abundance of eccDNAs carrying oncogene-segments in GCT may represent the DNA damage products of amplified oncogenes. Analysis of GCT over-represented eccDNA carrying enhancer (eccEnhancer) based on data from FANTOM5 project combined with TCGA database suggested the GC over-represented eccEnhancers may contribute to development of GC. GC over-represented eccDNAs carrying pre-miRNA (eccMIR) were enriched to multiple cancer-relevant signal pathways by KEGG analysis. We then synthesized the top six GC over-represented eccMIRs and found four of them enabled high expression of miRNAs and down-regulation of miRNA-target genes in MGC803 cells. Furthermore, we observed the inheritance of GC over-represented eccMIRs benefited host cell proliferation and promoted the aggressive features of host cells. Altogether, this study revealed the GC over-represented eccDNAs carrying functional genomic segments were related to the carcinogenesis of GC and presented the capability to facilitate cancer progression, suggesting the cancerous eccDNAs may serve as a dynamic reservoir for genome plasticity and rapid adaptive evolution of cancer. Therefore, blocking the pathways for eccDNAs generation may provide a novel therapeutic strategy for the treatment of gastric cancer.
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Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , ADN Circular/genética , Genoma , ADN , Carcinogénesis/genéticaRESUMEN
OBJECTIVES: Oral diseases, such as dental caries, periodontitis, and oral cancers, are highly prevalent worldwide. Many oral diseases are typically associated with bacterial infections or the proliferation of malignant cells, and they are usually located superficially. MATERIALS AND METHODS: Articles were retrieved from PubMed/Medline, Web of Science. All studies focusing on stimuli-responsive materials in oral diseases were included and carefully evaluated. RESULTS: Stimulus-responsive materials are innovative materials that selectively undergo structural changes and trigger drug release based on shifts at the molecular level, such as changes in pH, electric field, magnetic field, or light in the surrounding environment. These changes lead to alterations in the properties of the materials at the macro- or microscopic level. Consequently, stimuli-responsive materials are particularly suitable for treating superficial site diseases and have found extensive applications in antibacterial and anticancer therapies. These characteristics make them convenient and effective for addressing oral diseases. CONCLUSIONS: This review aimed to summarize the classification, mechanism of action, and application of stimuli-responsive materials in the treatment of oral diseases, point out the existing limitations, and speculate the prospects for clinical applications. CLINICAL RELEVANCE: Our findings may provide useful information of stimuli-responsive materials in oral diseases for dental clinicians.
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Enfermedades de la Boca , Humanos , Enfermedades de la Boca/terapia , Enfermedades de la Boca/tratamiento farmacológico , Concentración de Iones de Hidrógeno , Materiales Dentales/químicaRESUMEN
BACKGROUND: Intestinal senescence is associated with several aging-related diseases. l-Theanine (LTA) has demonstrated strong potential as an antioxidant and antisenescence agent. This study investigated the regulatory effect of LTA on cellular senescence using an in vitro model of d-galactose (D-Gal)-induced senescence in the rat epithelial cell line, intestinal epithelioid cell-6 (IEC-6). RESULTS: Treatment of IEC-6 cells with 40 mg/mL D-Gal for 48 h resulted in the successful development of the senescent cell model. Compared with D-Gal alone, both LTA preventive and delayed intervention increased cell viability and the ratio of JC-1 monomers to aggregates, increased the antioxidant capacity, and decreased the advanced glycation end product (AGE) levels and the overall number of senescent cells. Preventive and delayed intervention with 1000 µM LTA alleviated the D-Gal-induced cell cycle arrest by regulating p38, p53, CDK4, and CDK6 expression at the mRNA and protein levels, and further induced CycD1 proteins. Moreover, LTA preventive intervention reduced apoptosis to a greater degree than delayed intervention by upregulating the expression of the receptors of AGEs, Bax, Bcl-2, and NF-κB at the mRNA and protein levels. CONCLUSION: Our findings indicate that LTA intervention could attenuate senescence in IEC-6 cells by regulating the cell cycle and inhibiting apoptosis. © 2023 Society of Chemical Industry.
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Antioxidantes , Glutamatos , Estrés Oxidativo , Ratas , Animales , Antioxidantes/farmacología , Antioxidantes/metabolismo , Galactosa , Senescencia Celular , Ciclo Celular , Apoptosis , ARN Mensajero/metabolismo , Envejecimiento/metabolismoRESUMEN
During exogenous bone-graft-mediated bone defect repair, macrophage inflammation dictates angiogenesis and bone regeneration. Exosomes from different human cells have shown macrophage immunomodulation-mediated bone regeneration potential. However, the effect of human serum-derived exosomes (serum-Exo) on macrophage immunomodulation-mediated angiogenesis during bone defect repair has not been investigated yet. In this study, we explored the effects of serum-Exo on macrophage inflammation regulation-mediated angiogenesis during bone defect repair and preliminarily elucidated the mechanism. Healthy serum-Exo was isolated by ultracentrifugation. The effect of serum-Exo on LPS-induced M1 macrophage inflammation was analysed in vitro. The conditioned medium of serum-Exo-treated LPS-induced M1 macrophage (serum-Exo-treated M1 macrophage-CM) was used to culture human umbilical vein endothelial cells (HUVEC), and the effect on angiogenesis was analysed by western blot, qRT-PCR, etc. mRNA-sequencing of HUVECs was performed to identify deferentially expressed genes. Finally, the rat mandibular defect model was established and treated with Bio-Oss and Bio-Oss + Exo. The effect of the Bio-Oss + Exo combination on mandibular bone regeneration was observed by micro-computed tomography (micro-CT), haematoxylin and eosin (HE) staining, Masson staining, and immunohistochemical staining. Serum-Exo promoted the proliferation of RAW264.7 macrophages and reduced the expression of M1-related genes such as IL-6, IL-1ß, iNOS, and CD86. Serum-Exo-treated M1 macrophage-CM induced the proliferation, migration, and angiogenic differentiation of HUVEC, as well as the expression of H-type blood vessel markers CD31 and endomucin (EMCN), compared with M1 macrophage-CM. Moreover, higher expression of vascular endothelial adhesion factor 1 (VCAM1) in HUVEC cultured with serum-Exo-treated M1 macrophage-CM compared with M1 macrophages-CM. Inhibition of VCAM1 signalling abrogated the pro-angiogenic effect of serum-Exo-treated M1 macrophage-CM on HUVEC. Local administration of serum-Exo during mandibular bone defect repair reduced the number of M1 macrophages and promoted angiogenesis and osteogenesis. Collectively, our results demonstrate the macrophage inflammation regulation-mediated pro-angiogenic potential of serum-Exo during bone defect repair possibly via upregulation of VCAM1 signalling in HUVEC.
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Exosomas , Humanos , Ratas , Animales , Exosomas/metabolismo , Lipopolisacáridos/metabolismo , Microtomografía por Rayos X , Regeneración Ósea/genética , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Inflamación/genética , Inflamación/metabolismo , MacrófagosRESUMEN
The external-stimulation-induced reactive-oxygen-species (ROS) generation has attracted increasing attention in therapeutics for malignant tumors. However, engineering a nanoplatform that integrates with efficient biocatalytic ROS generation, ultrasound-amplified ROS production, and simultaneous relief of tumor hypoxia is still a great challenge. Here, we create new semiconducting titanate-supported Ru clusterzymes (RuNC/BTO) for ultrasound-amplified biocatalytic tumor nanotherapies. The morphology and chemical/electronic structure analysis prove that the biocatalyst consists of Ru nanoclusters that are tightly stabilized by Ru-O coordination on BaTiO3 . The peroxidase (POD)- and halogenperoxidase-like biocatalysis reveals that the RuNC/BTO can produce abundant â¢O2 - radicals. Notably, the RuNC/BTO exhibits the highest turnover number (63.29 × 10-3 s-1 ) among the state-of-the-art POD-mimics. Moreover, the catalase-like activity of the RuNC/BTO facilitates the decomposition of H2 O2 to produce O2 for relieving the hypoxia of the tumor and amplifying the ROS level via ultrasound irradiation. Finally, the systematic cellular and animal experiments have validated that the multi-modal strategy presents superior tumor cell-killing effects and suppression abilities. We believe that this work will offer an effective clusterzyme that can adapt to the tumor microenvironment-specific catalytic therapy and also provide a new pathway for engineering high-performance ROS production materials across broad therapeutics and biomedical fields.
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Neoplasias , Rutenio , Animales , Biocatálisis , Especies Reactivas de Oxígeno , Neoplasias/terapia , Ultrasonografía , Peroxidasa , Peroxidasas , Colorantes , Oxígeno , Microambiente Tumoral , Línea Celular TumoralRESUMEN
The glycan loop of Zika virus (ZIKV) envelope protein (E) contains the glycosylation site and has been well documented to be important for viral pathogenesis and transmission. In the present study, we report that deletions in the E glycan loop, which were recorded in African ZIKV strains previously, have re-emerged in their contemporary Asian lineages. Here, we generated recombinant ZIKV containing specific deletions in the E glycan loop by reverse genetics. Extensive in vitro and in vivo characterization of these deletion mutants demonstrated an attenuated phenotype in an adult A129 mouse model and reduced oral infections in mosquitoes. Surprisingly, these glycan loop deletion mutants exhibited an enhanced neurovirulence phenotype, and resulted in a more severe microcephalic brain in neonatal mouse models. Crystal structures of the ZIKV E protein and a deletion mutant at 2.5 and 2.6 Å, respectively, revealed that deletion of the glycan loop induces encephalitic flavivirus-like conformational alterations, including the appearance of perforations on the surface and a clear change in the topology of the loops. Overall, our results demonstrate that the E glycan loop deletions represent neonatal mouse neurovirulence markers of ZIKV. IMPORTANCE Zika virus (ZIKV) has been identified as a cause of microcephaly and acquired evolutionary mutations since its discovery. Previously deletions in the E glycan loop were recorded in African ZIKV strains, which have re-emerged in the contemporary Asian lineages recently. The glycan loop deletion mutants are not glycosylated, which are attenuated in adult A129 mouse model and reduced oral infections in mosquitoes. More importantly, the glycan loop deletion mutants induce an encephalitic flavivirus-like conformational alteration in the E homodimer, resulting in a significant enhancement of neonatal mouse neurovirulence. This study underscores the critical role of glycan loop deletion mutants in ZIKV pathogenesis, highlighting a need for global virological surveillance for such ZIKV variants.
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Proteínas del Envoltorio Viral , Infección por el Virus Zika , Virus Zika , Animales , Ratones , Modelos Animales de Enfermedad , Polisacáridos/química , Proteínas del Envoltorio Viral/genética , Virulencia , Replicación Viral/genética , Virus Zika/genética , Virus Zika/patogenicidad , Infección por el Virus Zika/virologíaRESUMEN
INTRODUCTION: To establish an animal model of delayed intravenous resuscitation following seawater immersion after hemorrhagic shock (HS). METHODS: Adult male SD rats were randomly divided into three groups: group NI (HS with no immersion), group SI (HS with skin immersion), and group VI (HS with visceral immersion). Controlled HS in rats was induced by withdrawing 45% of the calculated total blood volume within 30 min. In SI group, immediately after blood loss, 0.5 cm below the xiphoid process was immersed in artificial seawater, at (23 ± 1) °C, for 30 min. In VI group, the rats were performed by laparotomy and the abdominal organs were immersed in (23 ± 1) °C seawater for 30 min. Two hours after seawater immersion, the extractive blood and lactated Ringer's solution were delivered intravenously. The mean arterial pressure (MAP), lactate, and other biological parameters were investigated in different time points. The survival rate of 24 h after HS was recorded. RESULTS: After seawater immersion following HS, MAP and abdominal viscera blood flow decreased significantly, and the plasma levels of lactate and the organ function parameters were increased than the baseline. The above changes in VI group were more serious than those in SI and NI group, especially in myocardial and small intestine damage. The hypothermia, hypercoagulation, and metabolic acidosis were also observed after seawater immersion; the injury was more severely in VI group than that of SI group. However, the plasma levels of sodium, potassium, chlorine, and calcium in VI group were significantly higher than those before injury and in the other two groups. In the VI group, the level of plasma osmolality in instant, 2 h, and 5 h after immersion was 111%, 109%, and 108% of the SI group, respectively, all P < 0.01. The 24-h survival rate of VI group was 25%, which was significantly lower than that of SI group (50%) and NI group (70%), P < 0.05. CONCLUSIONS: The model fully simulated the key damage factors and field treatment conditions, reflected the effects of low temperature and hypertonic damage caused by seawater immersion on the severity and prognosis of naval combat wounds, and provided a practical and reliable animal model for the study of field treatment technology of marine combat shock.
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Choque Hemorrágico , Ratas , Masculino , Animales , Choque Hemorrágico/complicaciones , Choque Hemorrágico/terapia , Ratas Sprague-Dawley , Modelos Animales de Enfermedad , Hemorragia , Resucitación , Ácido LácticoRESUMEN
PURPOSE: Streptococcus pneumoniae (Spn) is a major cause of child death. We investigated the epidemiology of S. pneumoniae in a pediatric fever clinic and explored the genomics basis of the limited vaccine response of serotype 14 strains worldwide. METHODS: Febrile disease and pneumonia were diagnosed following criteria from the WHO at the end of 2019 at a tertiary children's hospital. Spn was isolated by culture from nasopharyngeal (NP) swabs. The density was determined by lytA-base qPCR. Isolates were serotyped by Quellung and underwent antimicrobial susceptibility testing. Whole-genome sequencing was employed for molecular serotyping, MLST, antibiotic gene determination, SNP calling, recombination prediction, and phylogenetic analysis. RESULTS: The presence of pneumococcus in the nasopharynx (87.5%, 7/8, p = 0.0227) and a high carriage (100%, 7/7, p = 0.0123) were significantly associated with pneumonia development. Living with siblings (73.7%, 14/19, p = 0.0125) and non-vaccination (56.0%, 28/50, p = 0.0377) contributed significantly to the Spn carriage. Serotype 14 was the most prevalent strain (16.67%, 5/30). The genome analysis of 1497 serotype 14 strains indicated S14/ST876 strains were only prevalent in China, presented limited vaccine responses with higher recombination activities within its cps locus, and unique variation patterns in the genes wzg and lrp. CONCLUSION: With the lifting of the one-child policy, it will be crucial for families with multiple children to get PCV vaccinations in China. Due to the highly variant cps locus and distinctive variation patterns in capsule shedding and binding proteins genes, the prevalent S14/ST876 strains have shown poor response to current vaccines. It is necessary to continue monitoring the molecular epidemiology of this vaccine escape clone.
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BACKGROUND: Severe tuberculosis constitutes a significant menace to human safety and well-being, with a considerable mortality rate. The severity of tuberculosis can be impacted by genetic variations in host genes, particularly single nucleotide polymorphisms (SNPs). METHODS: A caseâcontrol study was undertaken, encompassing a cohort of 1137 tuberculosis patients (558 with severe tuberculosis and 579 with mild tuberculosis), alongside 581 healthy controls within the age range of fifteen to forty-five years. Whole blood DNA was extracted from all participants, and three tag polymorphisms (rs1884444, rs7518660, rs7539625) of the IL23R gene were selectively identified and genotyped. RESULTS: No significant correlation was observed between the IL23R gene polymorphisms (rs1884444, rs7518660, and rs7539625) and tuberculosis. Upon comparing the tuberculosis group with the healthy control group, the mild tuberculosis group with the healthy control group, and the severe tuberculosis group with the healthy control group, the obtained P-values were> 0.05. However, in the comparison between severe tuberculosis and mild tuberculosis, the presence of rs1884444 G alleles exhibited a significantly increased risk of severe tuberculosis after adjusting for age and sex (ORa: 1.199, 95% CI: 1.009-1.424; Pa=0.039, respectively). In subgroup analysis, after accounting for confounding factors, including age and sex, rs1884444 G alleles continued to demonstrate a significantly heightened risk of severe tuberculosis. Nonetheless, the comparison between the multisystemic tuberculosis group and the mild tuberculosis group was no significant difference. Notably, rs1884444 of the IL23R gene exhibited a noteworthy association with the risk of severe tuberculosis in the comparison between severe tuberculosis and mild tuberculosis before and after adjusting for age and sex (ORa: 1.301, 95% CI: 1.030-1.643; Pa=0.027, respectively). Furthermore, the presence of the rs1884444 G allele exhibited a significantly increased risk of severe tuberculosis after adjusting for age and sex in the comparison between tuberculous meningitis and mild tuberculosis (ORa: 1.646, 95% CI: 1.100-2.461; Pa=0.015, respectively). CONCLUSIONS: The present study suggests that there is no significant association between IL23R gene polymorphism and tuberculosis susceptibility in the Chinese Han population. However, it does indicate a potential link between IL23R polymorphism and an increased risk of developing severe tuberculosis.
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Polimorfismo de Nucleótido Simple , Tuberculosis , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Predisposición Genética a la Enfermedad , Estudios de Casos y Controles , Pueblos del Este de Asia , Genotipo , Tuberculosis/genética , Frecuencia de los Genes , Receptores de Interleucina/genéticaRESUMEN
Taxanes (Taxol/paclitaxel, Docetaxel/taxotere) are a key group of successful drugs commonly used in chemotherapy to treat several major malignant tumors also as a front-line agent in combination with carboplatin/cisplatin, as well as a second line drug with a dose dense regimen following recurrence. Overall, the response to paclitaxel is excellent, though drug resistance inevitably develops in subsequent treatments. The commonly accepted mechanism of action is that the hindrance of microtubule function by paclitaxel leads to cell cycle arrest at mitosis, and subsequent apoptosis. The mechanisms for resistance to paclitaxel have also been extensively investigated, such as ABC transporter overexpression, altered signaling and apoptotic gene expression to resist cell death, and changes associated with microtubules to reduce influences of the drugs. Meanwhile, another important mechanism of paclitaxel resistance has been proposed: increased nuclear lamina/envelope sturdiness to retard the breaking of nuclear envelop and the paclitaxel-induced multinucleation as well as the formation of multiple micronuclei. Here in this review, we focus on experimental findings and ideas on the mechanism of paclitaxel resistance related to cancer nuclear envelope, to provide new insights on overcoming paclitaxel resistance.
Asunto(s)
Neoplasias , Paclitaxel , Humanos , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Membrana Nuclear , Taxoides , Docetaxel , Cisplatino , Apoptosis , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Resistencia a Antineoplásicos/genéticaRESUMEN
The outbreak of coronavirus disease 2019 (COVID-19) has seriously affected the whole world, and epidemic research has attracted increasing amounts of scholarly attention. Critical facilities such as warehouses to store emergency supplies and testing or vaccination sites could help to control the spread of COVID-19. This paper focuses on how to locate the testing facilities to satisfy the varying demand, i.e., test kits, caused by pandemics. We propose a two-phase optimization framework to locate facilities and adjust capacity during large-scale emergencies. During the first phase, the initial prepositioning strategies are determined to meet predetermined fill-rate requirements using the sample average approximation formulation. We develop an online convex optimization-based Lagrangian relaxation approach to solve the problem. Specifically, to overcome the difficulty that all scenarios should be addressed simultaneously in each iteration, we adopt an online gradient descent algorithm, in which a near-optimal approximation for a given Lagrangian dual multiplier is constructed. During the second phase, the capacity to deal with varying demand is adjusted dynamically. To overcome the inaccuracy of long-term prediction, we design a dynamic allocation policy and adaptive dynamic allocation policy to adjust the policy to meet the varying demand with only one day's prediction. A comprehensive case study with the threat of COVID-19 is conducted. Numerical results have verified that the proposed two-phase framework is effective in meeting the varying demand caused by pandemics. Specifically, our adaptive policy can achieve a solution with only a 3.3% gap from the optimal solution with perfect information.