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N-heterocyclic carbene catalysis has been developed as a versatile method for the enantioselective synthesis of complex organic molecules in organic chemistry. Merging of N-heterocyclic carbene catalysis with transition metal catalysis holds the potential to achieve unprecedented transformations with broad substrate scope and excellent stereoselectivity, which are unfeasible with individual catalyst. Thus, this dual catalysis has attracted increasing attention, and numerous elegant dual catalytic systems have been established. In this review, we summarize the recent achievements of dual NHC/transition metal catalysis, including the reaction design, mechanistic studies and practical applications.
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In this study, we synthesized a coumarin-hemicyanine-based deep red fluorescent dye that exhibits an intramolecular charge transfer (ICT). The probe had a large Stokes shift of 287 nm and a large molar absorption coefficient (ε = 7.5 × 105 L·mol-1·cm-1) and is best described as a deep red luminescent fluorescent probe with λem = 667 nm. The color of probe W changed significantly when it encountered cyanide ions (CN-). The absorption peak (585 nm) decreased gradually, and the absorption peak (428 nm) increased gradually, so that cyanide (CN-) could be identified by the naked eye. Moreover, an obvious fluorescence change was evident before and after the reaction under irradiation using 365 nm UV light. The maximum emission peak (667 nm) decreased gradually, whilst the emission peak (495 nm) increased gradually, which allowed for the proportional fluorescence detection of cyanide (CN-). Using fluorescence spectrometry, the fluorescent probe W could linearly detect CN- over the concentration range of 1-9 µM (R2 = 9913, RSD = 0.534) with a detection limit of 0.24 µM. Using UV-Vis spectrophotometry, the linear detection range for CN- was found to be 1-27 µM (R2 = 0.99583, RSD = 0.675) with a detection limit of 0.13 µM. The sensing mechanism was confirmed by 1H NMR spectroscopic titrations, 13C NMR spectroscopy, X-ray crystallographic analysis and HRMS. The recognition and detection of CN- by probe W was characterized by a rapid response, high selectivity, and high sensitivity. Therefore, this probe provides a convenient, effective and economical method for synthesizing and detecting cyanide efficiently and sensitively.
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Cianuros , Colorantes Fluorescentes , Cianuros/química , Colorantes Fluorescentes/química , Carbocianinas , Cumarinas/química , Espectrometría de Fluorescencia/métodosRESUMEN
Axially chiral diaryl ethers are present in numerous natural products and bioactive molecules. However, only few catalytic enantioselective approaches have been established to access diaryl ether atropisomers. Herein, we report the N-heterocyclic carbene-catalyzed enantioselective synthesis of axially chiral diaryl ethers via desymmetrization of prochiral 2-aryloxyisophthalaldehydes with aliphatic alcohols, phenol derivatives, and heteroaromatic amines. This reaction features mild reaction conditions, good functional group tolerance, broad substrate scope and excellent enantioselectivity. The utility of this methodology is illustrated by late-stage functionalization, gram-scale synthesis, and diverse enantioretentive transformations. Control experiments and DFT calculations support the association of NHC-catalyzed desymmetrization with following kinetic resolution to enhance the enantioselectivity.
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BACKGROUND: Persistent high-risk human papillomavirus (HR-HPV) infection is an important factor in the development of cervical cancer, and human papillomavirus type 16 (HPV-16) is the most common HR-HPV type worldwide. The oncogenic potential of HPV-16 is closely related to viral sequence variation. METHODS: In order to clarify the variant characteristics of HPV-16 E6 and E7 genes in central China, E6 and E7 sequences of 205 HPV-16 positive samples were amplified by polymerase chain reaction. PCR products of E6 and E7 genes were further sequenced and subjected to variation analysis, phylogenetic analysis, selective pressure analysis and B-cell epitope prediction. RESULTS: Twenty-six single nucleotide variants were observed in E6 sequence, including 21 non-synonymous and 5 synonymous variants. Twelve single nucleotide variants were identified in E7 sequence, including 6 non-synonymous and 6 synonymous variants. Four new variants were found. Furthermore, nucleotide variation A647G (N29S) in E7 was significantly related to the higher risk of HSIL and cervical cancer. Phylogenetic analysis showed that the E6 and E7 sequences were all distributed in A lineage. No positively selected site was found in HPV-16 E6 and E7 sequences. Non-conservative substitutions in E6, H31Y, D32N, D32E, I34M, L35V, E36Q, L45P, N65S and K75T, affected multiple B-cell epitopes. However, the variation of E7 gene had little impact on the corresponding B-cell epitopes (score < 0.85). CONCLUSION: HPV-16 E6 and E7 sequences variation data may contribute to HR-HPV prevention and vaccine development in Jingzhou, central China.
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Papillomavirus Humano 16 , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Femenino , Humanos , China/epidemiología , Epítopos de Linfocito B/genética , Variación Genética , Papillomavirus Humano 16/genética , Virus del Papiloma Humano , Nucleótidos , Infecciones por Papillomavirus/epidemiología , Filogenia , Neoplasias del Cuello Uterino/epidemiologíaRESUMEN
Acute ischemic stroke (AIS) is a serious and life-threatening disease worldwide. Despite thrombolysis or endovascular thrombectomy, a sizeable fraction of patients with AIS have adverse clinical outcomes. In addition, existing secondary prevention strategies with antiplatelet and anticoagulant drugs therapy are not able to adequately decrease the risk of ischemic stroke recurrence. Thus, exploring novel mechanisms for doing so represents an urgent need for the prevention and treatment of AIS. Recent studies have discovered that protein glycosylation plays a critical role in the occurrence and outcome of AIS. As a common co- and post-translational modification, protein glycosylation participates in a wide variety of physiological and pathological processes by regulating the activity and function of proteins or enzymes. Protein glycosylation is involved in two causes of cerebral emboli in ischemic stroke: atherosclerosis and atrial fibrillation. Following ischemic stroke, the level of brain protein glycosylation becomes dynamically regulated, which significantly affects stroke outcome through influencing inflammatory response, excitotoxicity, neuronal apoptosis, and blood-brain barrier disruption. Drugs targeting glycosylation in the occurrence and progression of stroke may represent a novel therapeutic idea. In this review, we focus on possible perspectives about how glycosylation affects the occurrence and outcome of AIS. We then propose the potential of glycosylation as a therapeutic drug target and prognostic marker for AIS patients in the future.
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Isquemia Encefálica , Accidente Cerebrovascular Isquémico , Humanos , Isquemia Encefálica/terapia , Glicosilación , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Accidente Cerebrovascular Isquémico/complicaciones , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/epidemiología , Resultado del TratamientoRESUMEN
An NHC-catalyzed atroposelective synthesis of axially chiral α-carbolinones from α,ß-unsaturated iminoindole derivatives and α-chloroaldehydes was developed. The reaction proceeds through a cascade process including [4 + 2] annulation and then oxidative dehydrogenation with concomitant central-to-axial chirality conversion under mild conditions. The developed method opens a new avenue to efficiently access axially chiral α-carbolinones in moderate to good enantioselectivities.
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BACKGROUND: Toll-like receptors (TLRs) may be involved in the natural history of human papillomavirus (HPV) infection. In our study, we aimed to investigate the association of TLR4 (rs10116253, rs1927911, rs10759931) and TLR9 (rs187084, rs352140) gene polymorphisms with cervical persistent high-risk HPV (HR-HPV) infection, as well as multiple HR-HPV infections. METHODS: A total of 269 study subjects were enrolled and grouped by retrospectively analyzing the HR-HPV testing results and other clinical data of 2647 gynecological outpatients from Jingzhou Hospital Affiliated to Yangtze University. We conducted a case-control study to compare the role of TLR4/TLR9 gene polymorphisms between HR-HPV transient and persistent infections, as well as between HR-HPV single and multiple infections. HR-HPV genotypes were detected using Real-time polymerase chain reaction (RT-PCR). PCR-restriction fragment length polymorphism (PCR-RFLP) was used to determine TLR4 and TLR9 gene polymorphisms. Analyses of the different outcome variables (HR-HPV infection status and time for HR-HPV clearance) with respect to TLR4/TLR9 polymorphisms were carried out. Logistic regression analysis was used to determine the association of TLR4/TLR9 genotypes and alleles with HR-HPV infection status. The Kaplan-Meier method with the log-rank test was used to analyze the relationship between TLR4/TLR9 genotypes and the time for HR-HPV clearance. RESULTS: The mutant genotypes of TLR9 rs187084 and rs352140 were associated with persistent (rs187084: CT and CT+CC; rs352140: CT and CT+TT) and multiple (rs187084: CT and CT+CC; rs352140: CT+TT) (all P < 0.05) HR-HPV infection. However, no association was found between TLR4 polymorphisms and HR-HPV infection status. Kaplan-Meier time to HR-HPV clearance analysis demonstrated that women carrying rs187084 and rs352140 mutant genotypes take longer duration to clear HR-HPV infection compared with wild-type genotype carriers (P1 = 0.012; P2 = 0.031). CONCLUSION: Our results suggested that TLR9 polymorphisms, but not TLR4, were associated with cervical persistent and multiple HR-HPV infections, which could be useful as a potential predictor of HR-HPV infection status.
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Infecciones por Papillomavirus , Receptor Toll-Like 4 , Receptor Toll-Like 9 , Femenino , Humanos , Estudios de Casos y Controles , Pueblos del Este de Asia , Predisposición Genética a la Enfermedad , Genotipo , Infecciones por Papillomavirus/genética , Polimorfismo de Nucleótido Simple , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , Receptor Toll-Like 4/genética , Receptor Toll-Like 9/genéticaRESUMEN
Accumulating evidence has shown that many long non-coding RNAs (lncRNA) participate in the tumorigenesis, including osteosarcoma (OS). Of them, lncRNA ODRUL was previously reported to act as a possible oncogene in OS doxorubicin resistance. However, the underlying molecular mechanism of ODRUL involved in the progression of OS still remains to be thoroughly investigated. In the current study, we reported another mechanism by which ODRUL regulates OS progression. QRT-PCR and WB were conducted to detect ODRUL, miR-6874-3p and IL-6 expression in OS tissues and cells. The Kaplan-Meier was used to assess the relevance between the expression level of miR-6874-3p and the overall survival of OS patients. Wound healing assays and Transwell assays were used to evaluate the invasion and migration of OS cells. Furthermore, the binding sites of ODRUL and IL-6 to miR-6874-3p were predicted by bioinformatics and verified by dual-luciferase reporter gene assays. ODRUL and IL-6 were highly expressed in OS cells and tissues, while miR-6874-3p was expressed at low levels. The overall survival of high miR-6874-3p expression of OS patients was longer than that of low miR-6874-3p expression of OS patients. MiR-6874-3p overexpression markedly inhibited the progression of OS cells. Both ODRUL and IL-6 could bind to miR-6874-3p at the predicted binding sites which were authenticated by dual-luciferase reporter gene assay. MiR-6874-3p could inhibit OS cell proliferation and metastasis and ODRUL could reverse the suppression induced by miR-6874-3p in vivo. In conclusion, ODRUL could effectively sponge miR-6874-3p to upregulate the expression of IL-6 in OS progression.
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Neoplasias Óseas/genética , Interleucina-6/genética , MicroARNs/genética , Osteosarcoma/genética , ARN Largo no Codificante/genética , Adulto , Neoplasias Óseas/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Masculino , Oncogenes/genética , Osteosarcoma/patología , Regulación hacia Arriba/genéticaRESUMEN
INTRODUCTION: There is a great debate on the routine use of open reduction and internal fixation (ORIF) for midshaft clavicle fractures, and one concern is the adverse events after ORIF, such as implant removal after bone union. In this retrospective study, we assessed the incidence, risk factors, management and outcomes of refracture after plate removal of midshaft clavicle fractures after bone union. MATERIALS AND METHODS: Three hundred fifty-two patients diagnosed with acute midshaft clavicle fractures who had complete medical records from primary fractures to refracture were recruited. Details of imaging materials and clinical characteristics were carefully reviewed and analysed. RESULTS: The incidence rate of refracture was 6.5% (23/352), and the average interval from implant removal to refracture was 25.6 days. Multivariate analysis showed that the risk factors were Robinson type-2B2 and fair/poor reduction. Females were 2.4 times more likely to have refracture, although it was not significant in multivariate analysis (p = 0.134). Postmenopausal females with a short interval (≤ 12 months) from primary surgery to implant removal had a significant risk for refracture. Tobacco use and alcohol use during bone healing were potential risk factors for male patients, although they were not significant in multivariate analysis. Ten patients received reoperation with or without bone graft, and they had a higher rate of bone union than 13 patients who refused reoperation. CONCLUSION: The incidence of refracture following implant removal after bone union is underestimated, and severe comminute fractures and unsatisfactory reduction during primary surgery are risk factors. Implant removal for postmenopausal female patients is not recommended due to a high rate of refracture.
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Fijación Interna de Fracturas , Fracturas Óseas , Humanos , Masculino , Femenino , Incidencia , Fijación Interna de Fracturas/efectos adversos , Fijación Interna de Fracturas/métodos , Clavícula/diagnóstico por imagen , Clavícula/cirugía , Estudios Retrospectivos , Fracturas Óseas/diagnóstico por imagen , Fracturas Óseas/epidemiología , Fracturas Óseas/cirugía , Factores de Riesgo , Placas Óseas/efectos adversos , Resultado del TratamientoRESUMEN
Osteosarcoma is a prevalent malignant bone tumor with a poor prognosis. Mothers against decapentaplegic homolog 3 (Smad3) present as a therapeutic target in antitumor treatment, whereas its functions in the osteosarcoma have not been well explored. In the current study, we aimed to investigate the effects of Smad3 in the progression of osteosarcoma. The tumor immune single-cell hub 2 website was used for graph-based visualization of Smad3 status in osteosarcoma single-cell database. Western Blot was applied to detect the expression of Smad3 protein in cell lines. Colony formation and cell counting kit-8 assays were used to evaluate cell proliferation. Transwell and wound healing assays were used to detect the migration and invasion abilities of cells. Cell apoptosis rates and cell cycle changes were explored by using flow cytometry analysis. The xenograft tumor growth model was applied to explore the effect in tumor growth after Smad3 blockage in vivo. Moreover, to confirm the potential mechanism of Smad3's effects on osteosarcoma, bioinformatics analysis was performed in TARGET-Osteosarcoma and GSE19276 databases. Our study found that the Smad3 protein is overexpressed in 143B and U2OS cells, suppressing the expression of Smad3 protein in osteosarcoma cells by Smad3 target inhibitor (E)-SIS3 or lentivirus can inhibit the proliferation, migration, invasion, promote cell apoptosis, arrest cell G1 cycle in osteosarcoma cells in vitro, and suppress tumor growth in vivo. Furthermore, the bioinformatics analysis demonstrated that high expression of Smad3 is closely associated with low immune status in TARGET-Osteosarcoma and GSE19276 databases. Our study suggested that Smad3 could contribute positively to osteosarcoma progression via the regulation of tumor immune microenvironment, and Smad3 may represent as an valuable potential therapeutic target in osteosarcoma therapy.
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Neoplasias Óseas , Osteosarcoma , Humanos , Proteína smad3 , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/metabolismo , Osteosarcoma/patología , Apoptosis , Ciclo Celular , Proliferación Celular , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Línea Celular Tumoral , Movimiento Celular , Microambiente TumoralRESUMEN
Renal ischemia-reperfusion (I/R) injury is a leading cause of acute kidney injury (AKI), with high mortality. Recent studies have reported that human umbilical cord mesenchymal stem cells (HucMSCs) play an important role in repairing organ and tissue injuries because of their unique characteristics. However, the potential of HucMSC extracellular vesicles (HucMSC-EVs) to promote the repair of renal tubular cells remains to be explored. This study found that HucMSC-EVs derived from HucMSCs played a protective role and were associated with kidney I/R injury. We found that miR-148b-3p in HucMSC-EVs had a protective effect against kidney I/R injury. HK-2 cells overexpressing miR-148b-3p were protected against I/R injury by inhibiting apoptosis. Next, the target mRNA of miR-148b-3p was predicted online, and the target mRNA, pyruvate dehydrogenase kinase 4 (PDK4), was identified and verified using dual luciferase. We discovered that I/R injury significantly increased endoplasmic reticulum (ER) stress, whereas siR-PDK4 inhibited these effects and protected against I/R injury. Interestingly, after administrating HucMSC-EVs to HK-2 cells, PDK4 expression and ER stress induced by I/R injury were significantly inhibited. HK-2 ingested miR-148b-3p from HucMSC-EVs, and its ER induced by I/R injury was significantly deregulated. This study suggests that HucMSC-EVs protect kidneys from I/R injury during the early I/R stage. These results suggest a new mechanism for HucMSC-EVs in treating AKI and provide a new treatment strategy for I/R injury.
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Lesión Renal Aguda , Vesículas Extracelulares , Células Madre Mesenquimatosas , MicroARNs , Daño por Reperfusión , Humanos , Riñón/metabolismo , Vesículas Extracelulares/metabolismo , Lesión Renal Aguda/metabolismo , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Reperfusión , Células Madre Mesenquimatosas/metabolismo , Estrés del Retículo Endoplásmico/genética , Cordón Umbilical/metabolismoRESUMEN
N-heterocyclic carbene (NHC)-catalyzed enantioselective Mannich-type reactions of the biomass-derived platform compound 5-(chloromethyl)furfural (CMF) with imines were developed. A series of high-value-added chiral amines were afforded in good to high yields with excellent regio- and enantioselectivities. The bifunctional NHC derived from Ê-pyroglutamic acid efficiently steered the remote addition of the trienolate intermediate to the imine in a highly stereocontrolled manner. This represents the first enantioselective reaction proceeding via an NHC-bound trienolate intermediate.
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In female mammals, the size of the initially established primordial follicle pool within the ovaries determines the reproductive life span. Interestingly, the establishment of the primordial follicle pool is accompanied by a remarkable programmed oocyte loss for unclear reasons. Here, we identify a new role of ASH1-like histone lysine methyltransferase (ASH1L) in controlling the apoptosis of oocytes during meiotic prophase I in mice. Our results showed that overexpression of Ash1l led to a dramatic loss of fetal oocytes via apoptosis, which subsequently resulted in a reduced capacity of the primordial follicle pool. Overexpression of Ash1l also led to a deficiency in DNA double-strand break repair associated with premature upregulation of p63 and phosphorylated checkpoint kinase 2 (p-CHK2), the major genome guardian of the female germline, following Ash1l overexpression in fetal ovaries. In summary, ASH1L is one of the indispensable epigenetic molecules that acts as a guardian of the genome. It protects oocyte genome integrity and removes oocytes with serious DNA damage by regulating the expression of p63 and p-CHK2 during meiotic prophase I in mice. Our study provides a perspective on the physiological regulatory role of DNA damage checkpoint signaling in fetal oocyte guardianship and female fertility.
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Meiosis , Oocitos , Animales , Apoptosis/genética , Quinasa de Punto de Control 2/genética , Quinasa de Punto de Control 2/metabolismo , Daño del ADN , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Femenino , N-Metiltransferasa de Histona-Lisina/genética , N-Metiltransferasa de Histona-Lisina/metabolismo , Mamíferos/metabolismo , Ratones , Oocitos/metabolismoRESUMEN
BACKGROUND: Tumour angiogenesis is an independent risk factor for bladder urothelial carcinoma (BUC) progression, but viable and promising antiangiogenic targets are understudied. Emerging evidence suggests that long non-coding RNAs (lncRNAs) play prominent role in the tumour microenvironment and tumour angiogenesis. METHODS: The clinical data of BUC patients were obtained from TCGA database and clinical specimens of 138 BUC patients. Univariate and multivariate COX regression analyses were used to identify survival-related ARLNRs (sARLNRs) from The Molecular Signatures Database v4.0. Fisher's exact probability method was used to detect the correlations between sARLNRs levels and clinicopathological characteristics. A chain of experiments including FACS, qPCR, immunohistochemistry, tube formation, migration and invasion assays, combining with co-culture models, were utilized to validate the clinical significance and angiogenetic correlation of sARLNRs. RESULTS: Five sARLNRs were employed to establish an angiogenesis-related risk score model, by which patients in the low-risk group obtained better overall survival than those in the high-risk group. The expression of AC005625.1 and AC008760.1 was significantly related to ECs percentage, tumour size and muscle invasion status. Besides, AC005625.1 and AC008760.1 expressed lower in BUC cell lines and tumour tissues than that in normal urothelial cells and adjacent normal tissues, with much lower levels in more advanced T stages. A prominently higher proportion of ECs was detected in tumour tissues with lower expression of AC005625.1 and AC008760.1. In the co-culture models, we found that knockdown of AC005625.1 and AC008760.1 in BUC cells increased the tube formation, migration and invasion abilities of HUVEC. The expression levels of CD31, VEGF-A, VIMENTIN and N-CADHERIN were also enhanced in HUVEC cells co-cultured with siR-AC005625.1 and siR-AC008760.1-treated T24 cells. CONCLUSION: In the study, we identify five sARLNRs and validate their clinical significance, angiogenesis correlation and prognosis-predictive values in BUC. These findings may provide a new perspective and some promising antiangiogenic targets for clinical diagnosis and treatment strategies of BUC.
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BACKGROUND: Cervical cancer is a common malignant tumor in women, with a high mortality rate, has great harm to women's health. Long-term and persistent infection of high-risk human papillomavirus (HR-HPV) is the main reason of the occurrence and development of cervical cancer. METHODS: The infection rate of HPV-58 is higher in the Jingzhou area. In this study, 172 complete HPV-58 E6-E7 sequences were amplified by polymerase chain reaction (PCR), the amplified products were sequenced, and the gene variations of HPV-58 E6-E7 were analyzed. A Neighbor-Joining phylogenetic tree was constructed by MEGA 11. The secondary structure of E6 and E7 protein was investigated. PAML X was used to analyze the selective pressure. The B cell epitopes of E6 and E7 proteins in HPV-58 were predicted by ABCpred server. RESULTS: In E6 sequences, 10 single nucleotide variants were observed, including 7 synonymous and 3 non-synonymous variants. In E7 sequences, 12 single nucleotide variants were found, including 3 synonymous variants and 9 non-synonymous variants. There are 5 novel variants. The phylogenetic analysis showed that all the E6-E7 sequences were distributed in A lineage. No positively selected site was found in E6 sequence, but G63 in E7 sequences was identified as positively selected site. Some amino acid substitutions affected multiple B cell epitopes. CONCLUSION: Various E6 and E7 mutational data may prove useful for development of better diagnostic and vaccines for the region of Jingzhou, Hubei province of central China.
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Alphapapillomavirus , Proteínas Oncogénicas Virales , Infecciones por Papillomavirus , Neoplasias del Cuello Uterino , Alphapapillomavirus/genética , China/epidemiología , Epítopos de Linfocito B , Femenino , Humanos , Nucleótidos , Proteínas Oncogénicas Virales/genética , Papillomaviridae/genética , Proteínas E7 de Papillomavirus/genética , Infecciones por Papillomavirus/epidemiología , Filogenia , Neoplasias del Cuello Uterino/epidemiologíaRESUMEN
When trains pass through damaged switch rails, rail head damage will change wheel-rail contact states from rolling frictions to unsteady contacts, which will result in impact vibrations and threaten structural safeties. In addition, under approaching and moving away rolling contact excitations and complex wheel-rail contacts, the non-stationary vibrations make it difficult to extract and analyze impact vibrations. In view of the above problems, this paper proposes a variational-mode-decomposition (VMD)-spectral-subtraction (SS)-based impact vibration extraction method. Firstly, the time domain feature analysis method is applied to calculate the time moments that the wheels pass joints, and to correct vehicle velocities. This can help estimate and confine impact vibration distribution ranges. Then, the stationary intrinsic mode function (IMF) components of the impact vibration are decomposed and analyzed with the VMD method. Finally, impact vibrations are further filtered with the SS method. For rail head damage with different dimensions, under different velocity experiments, the frequency and amplitude features of the impact vibrations are analyzed. Experimental results show that, in low-velocity scenarios, the proposed VMD-SS-based method can extract impact vibrations, the frequency features are mainly concentrated in 3500-5000 Hz, and the frequency and peak-to-peak features increase with the increase in excitation velocities.
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Diabetic retinopathy (DR) is one of the common complications in diabetic patients. Nowadays, VEGF pathway is subject to extensive research. However, about 27% of the patients have a poor visual outcome, with 50% still having edema after two years' treatment of diabetic macular edema (DME) with ranibizumab. Docosahexaenoic acid (DHA), the primary ω-3 long-chain polyunsaturated fatty acid (LC-PUFA), reduces abnormal neovascularization and alleviates neovascular eye diseases. A study reported that fish oil reduced the incidence of retinopathy of prematurity (ROP) by about 27.5% in preterm infants. Although ω-3 LC-PUFAs protects against pathological retinal neovascularization, the treatment effectiveness is low. It is interesting to investigate why DHA therapy fails in some patients. In human vitreous humor samples, we found that the ratio of DHA and DHA-derived metabolites to total fatty acids was higher in vitreous humor from DR patients than that from macular hole patients; however, the ratio of DHA metabolites to DHA and DHA-derived metabolites was lower in the diabetic vitreous humor. The expression of Mfsd2a, the LPC-DHA transporter, was reduced in the oxygen-induced retinopathy (OIR) model and streptozotocin (STZ) model. In vitro, Mfsd2a overexpression inhibited endothelial cell proliferation, migration and vesicular transcytosis. Moreover, Mfsd2a overexpression in combination with the DHA diet obviously reduced abnormal retinal neovascularization and vascular leakage, which is more effective than Mfsd2a overexpression alone. These results suggest that DHA therapy failure in some DR patients is linked to low expression of Mfsd2a, and the combination of Mfsd2a overexpression and DHA therapy may be an effective treatment.
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Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Retinopatía Diabética/metabolismo , Edema Macular/metabolismo , Simportadores/metabolismo , Animales , Línea Celular , Diabetes Mellitus Experimental/dietoterapia , Diabetes Mellitus Tipo 1/dietoterapia , Retinopatía Diabética/dietoterapia , Ácidos Docosahexaenoicos/administración & dosificación , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Femenino , Humanos , Masculino , Ratones Endogámicos C57BL , Retina/metabolismo , Simportadores/genética , Cuerpo Vítreo/metabolismo , Cicatrización de HeridasRESUMEN
The construction of a functional drug delivery system to reverse the multidrug resistance (MDR) of bone tumors in cases of failed chemotherapy remains a challenge. Herein, we demonstrate a selenium-doped calcium phosphate (Se-CaP) biomineral with high biocompatibility, biodegradability and pH-sensitive drug release properties. Se-CaP may not only serve as an effective drug-carrier to enhance the uptake of doxorubicin (DOX), but may also synchronously induce caspases-mediated apoptosis of osteosarcoma by generating intracellular reactive oxygen species (ROS). Furthermore, in vitro and in vivo studies obviously demonstrate that Se-CaP can reverse the MDR of osteosarcoma by down-regulating the expression of MDR-related ABC (ATP binding cassette) transporters proteins (ABCB1 and ABCC1). Finally, DOX-loaded Se-CaP can significantly inhibit DOX-resistant MG63 (MG63/DXR) tumor growth in nude mice. Considering its biomimetic chemical properties, the Se-CaP biomineral, with the multiple functions mentioned above, could be a promising candidate for treating bone tumors with MDR characteristics.
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Neoplasias Óseas/tratamiento farmacológico , Fosfatos de Calcio/química , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Minerales/química , Selenio/química , Neoplasias Óseas/patología , Muerte Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Humanos , Microesferas , Especies Reactivas de Oxígeno/metabolismo , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
As the major constituents of PM2.5, carbonaceous constituents and inorganic ions have attracted emerging attentions on their health risks, particularly on cardiorespiratory diseases. However, evidences on the risks of PM2.5 constituents on other diseases (eg. nervous disease, genitourinary disease, neoplasms and endocrine disease) remain scarce. In our study, we firstly calculated residuals of PM2.5 constituents regressed on PM2.5 to remove the confounding effect of PM2.5. Then, generalized additive model (GAM) was used to assess impacts of residuals of PM2.5 constituents on mortality from 36 diseases (10 broad categories and 26 subcategories) during 2011-2015 in Guangzhou, China. Results of constituent-residual models showed that only EC, OC and NO3- were significantly associated with all-cause mortality, with per IQR change in corresponding constituent residuals related to percentage changes of 1.69% (95% CI: 0.42, 2.97), 1.94% (95% CI: 0.37, 3.54) and 2.59% (95% CI: 1.02, 4.18) at lag 03 days. All these pollutants were significantly associated with elevated mortality risk of cardiovascular disease, but only EC was significantly associated with respiratory mortality, and NO3- with endocrine disease and neoplasm. For more specific causes, the highest effect estimates of EC and NO3-were both observed on mortality from other form of heart disease, and OC on intentional self-harm, with estimates of 11.45% (95% CI: 2.74, 20.91), 12.59% (95% CI: 1.41, 25.02) and 18.01% (95% CI: 2.14, 36.36), respectively. Our findings highlighted that stricter emission control measures are still warranted to reduce air pollution level and protect the public health.
Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Enfermedades Cardiovasculares , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Contaminación del Aire/efectos adversos , Contaminación del Aire/análisis , Enfermedades Cardiovasculares/inducido químicamente , China/epidemiología , Humanos , Material Particulado/análisis , Material Particulado/toxicidadRESUMEN
OBJECTIVE: To evaluate the clinical outcomes of negative-pressure wound therapy (NPWT) for infection prevention following pelvic reconstruction after malignant bone tumor resection. METHODS: The study involved 82 patients who underwent pelvic reconstruction following en-bloc resection of malignant bone tumors between January 2003 and January 2016. Forty patients were treated with NPWT via implantation of vacuum-sealing drainage (VSD) materials into the pelvic cavity to prevent infection and wound problems (VSD group), and the remaining 42 patients underwent conventional treatment (control group). Study authors compared the inpatient length of stay, antibiotic use, drainage volume, time to wound closure, and infection rates between groups. Investigators also conducted cell cultures of the wound cavity washing fluid and hematoxylin-eosin staining for VSD materials to find recurrent tumor cells. RESULTS: In the VSD group, one patient (2.5%) had a superficial wound problem. In the control group, 18 patients (42.9%) had deep infection or wound problems. The VSD group had a significantly decreased infection rate, duration of antibiotic administration and inpatient stay, as well as increased wound healing compared with the control group (P < .05). Further, no tumor cells were observed in the VSD material or the wound cavity washing fluid. CONCLUSIONS: The application of NPWT with VSD material may be an effective and reliable method for preventing infection in patients who undergo pelvic reconstruction following malignant tumor resection.