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BACKGROUND: The effects of metal exposure on semen quality and the role of oxidative damage in this process remain unclear. METHODS: We recruited 825 Chinese male volunteers, and 12 seminal metals (Mn, Cu, Zn, Se, Ni, Cd, Pb, Co, Ag, Ba, Tl, and Fe), the total antioxidant capacity (TAC), and reduced glutathione were measured. Semen parameters and GSTM1/GSTT1-null genotypes were also detected. Bayesian kernel machine regression (BKMR) was applied to evaluate the effect of the mixed exposure to metals on semen parameters. The mediation of TAC and moderation of GSTM1/GSTT1 deletion were analyzed. RESULTS: Most seminal metal concentrations were correlated with each other. The BKMR models revealed a negative association between the semen volume and metal mixture, with Cd (cPIP = 0.60) and Mn (cPIP = 0.10) as the major contributors. Compared to fixing all scaled metals at their median value (50th percentiles), fixing the scaled metals at their 75th percentiles decreased the TAC by 2.17 units (95%CI: -2.60, -1.75). Mediation analysis indicated that Mn decreased the semen volume, with 27.82% of this association mediated by TAC. Both the BKMR and multi-linear models showed that seminal Ni was negatively correlated with sperm concentration, total sperm count, and progressive motility, which was modified by GSTM1/GSTT1. Furthermore, Ni and the total sperm count showed a negative association in GSTT1 and GSTM1 null males (ß[95%CI]: 0.328 [-0.521, -0.136]) but not in males with GSTT1 and/or GSTM1. Although Fe and the sperm concentration and total sperm count were positively correlated, they showed inverse "U" shapes in univariate analysis. CONCLUSION: Exposure to the 12 metals was negatively associated with semen volume, with Cd and Mn as the major contributors. TAC may mediate this process. GSTT1 and GSTM1 can modify the reduction in the total sperm count caused by seminal Ni exposure.
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Antioxidantes , Glutationa Transferase , Análise do Sêmen , Adulto , Humanos , Masculino , Teorema de Bayes , Cádmio , População do Leste Asiático , Deleção de Genes , Metais/toxicidade , Sêmen , Glutationa Transferase/genética , ManganêsRESUMO
Regulation of quiescence is critical for the maintenance of adult hematopoietic stem cells (HSCs). Disruption of transcription factor gene Prdm16 during mouse embryonic development has been shown to cause a severe loss of fetal liver HSCs; however, the underlying mechanisms and the function of Prdm16 in adult HSCs remain unclear. To investigate the role of Prdm16 in adult HSCs, we generated a novel conditional knockout mouse model and deleted Prdm16 in adult mouse hematopoietic system using the IFN-inducible Mx1-Cre Our results show that Prdm16 deletion in the adult mouse hematopoietic system has a less severe effect on HSCs, causing a gradual decline of adult HSC numbers and a concomitant increase in the multipotent progenitor (MPP) compartment. Prdm16 deletion in the hematopoietic system following transplantation produced the same phenotype, indicating that the defect is intrinsic to adult HSCs. This HSC loss was also exacerbated by stress induced by 5-fluorouracil injections. Annexin V staining showed no difference in apoptosis between wild-type and knockout adult HSCs. In contrast, Bromodeoxyuridine analysis revealed that loss of Prdm16 significantly increased cycling of long-term HSCs (LT-HSCs) with the majority of the cells found in the S to G2/M phase. Consistently, RNA sequencing analysis of mouse LT-HSCs with and without Prdm16 deletion showed that Prdm16 loss induced a significant decrease in the expression of several known cell cycle regulators of HSCs, among which Cdkn1a and Egr1 were identified as direct targets of Prdm16 Our results suggest that Prdm16 preserves the function of adult LT-HSCs by promoting their quiescence.
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Células-Tronco Adultas/fisiologia , Ciclo Celular/genética , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Hematopoéticas/fisiologia , Fatores de Transcrição/metabolismo , Ativação Transcricional , Animais , Inibidor de Quinase Dependente de Ciclina p21/genética , Proteínas de Ligação a DNA/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Transplante de Células-Tronco Hematopoéticas , Camundongos , Camundongos Knockout , RNA-Seq , Fatores de Transcrição/genéticaRESUMO
Regulating catalytic activity plays an important role in further optimizing and developing multifunctional catalysts with high selectivity and high activity. Reversible dual regulation of catalytic activity has always been a challenging task. Here, we prepared poly(N-isopropylacrylamide)-anchored gold nanoparticles (AuNP@CDs-Azo-PNIPAM) through host-guest interaction of cyclodextrin capped gold nanoparticles (AuNP@CDs) and azobenzene-terminated poly(N-isopropylacrylamide) (Azo-PNIPAM). Azo-PNIPAM as thermal and light responsive ligand allows reversible dual regulation of catalytic activity. When the temperature is higher than the lowest critical solution temperature, the PNIPAM chain shrinks rapidly, increasing the steric hindrance around AuNPs and reducing the catalytic activity. Under ultraviolet light irradiation,cis-azobenzene disassembles from cyclodextrin and the number of surface active sites of AuNPs increases, which improves the catalytic activity. The reaction rate of UV irradiation is almost 1.3 times that of visible light irradiation. This work provides a simple and effective strategy for the construction of reversible catalysts.
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Acquisition of self-renewal capability by myeloid progenitors to become leukemic stem cells during myeloid leukemia development is poorly understood. Here, we show that Setbp1 overexpression efficiently confers self-renewal capability to myeloid progenitors in vitro, causing their immortalization in the presence of stem cell factor and IL-3. Self-renewal after immortalization requires continuous Setbp1 expression. We also found that Hoxa9 and Hoxa10 mRNA are present at dramatically higher levels in Setbp1-immortalized cells compared with other immortalized cells, and are induced shortly after Setbp1 expression in primary myeloid progenitors. Suppression of either gene in Setbp1-immortalized cells drastically reduces their colony-forming capability. Interestingly, Setbp1 protein associates with Hoxa9 and Hoxa10 promoters in chromatin immunoprecipitation assays in these cells, suggesting that both are direct transcriptional targets of Setbp1. Setbp1 also promotes self-renewal of myeloid progenitors in vivo as its coexpression with BCR/ABL transforms primary mouse myeloid progenitors, generating aggressive leukemias in recipient mice resembling chronic myelogenous leukemia (CML) myeloid blast crisis. Increased SETBP1 mRNA levels were also detected in a subset of CML advanced phase/blast crisis patients with high levels of HOXA9 and HOXA10 expression. Thus, Setbp1 activation represents a novel mechanism conferring self-renewal capability to myeloid progenitors in myeloid leukemia development.
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Proteínas de Transporte/fisiologia , Proliferação de Células , Proteínas de Homeodomínio/genética , Células Progenitoras Mieloides/fisiologia , Proteínas Nucleares/fisiologia , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Células Cultivadas , Proteínas Homeobox A10 , Proteínas de Homeodomínio/metabolismo , Proteínas de Homeodomínio/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Células Progenitoras Mieloides/metabolismo , Células NIH 3T3 , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Ativação Transcricional/fisiologia , TransfecçãoRESUMO
OBJECTIVE: To compare the clinical efficacy of 3 different treatment programs for oligospermia patients of Shen-essence deficiency syndrome (SEDS). METHODS: Totally 450 male patients were randomly assigned to 3 groups, i.e., the treatment group, the control group 1, and the control group 2, 150 in each group. Patients in the treatment group were treated by Bushen Yijing Decoction (BYD), tamoxifen tablet (TT), Licorzine Capsule (LC), and Vitamin E Soft Capsule (VESC). Those in the control group 1 were treated by BYD, LC, and VESC. Those in the control group 2 were treated by TT, LC, and VESC. All patients were treated for 3 months. Their pregnant rates were compared. Clinical efficacies of each Chinese medical symptom and sperm parameters [sperm density, grade a sperm motility rate, grade (a + b) sperm motility rate, grade (a + b + c) sperm motility rate, and normal sperm morphology rate] were compared before and after treatment. RESULTS: At 3 months after treatment 61 patients were pregnant in the treatment group, 36 patients were pregnant in the control group 1, and 30 patients were pregnant in the control group 2. The differences in the sperm density, grade a sperm motility rate, and grade (a + b) sperm motility rate, and grade (a + b + c) sperm motility rate between before and after treatment were significantly higher in the treatment group than in the control group 1 and the control group 2 (P < 0.01). The difference in the normal sperm morphology rate between before and after treatment was obviously higher in the treatment group and the control group 1 than in the control group 2 (P < 0.01). Better results were obtained in the treatment group and the control group 1 in improving the sexual apathy, soreness and weakness of waist and knees, impotence, premature ejaculation, seminal emission, dizziness, tinnitus, forgetfulness, alopecia, when compared with the control group 2 (P < 0.01, P < 0.05). There was no statistical difference in the total effective rate of improving Chinese medical symptoms between the treatment group and the control group 1 (P > 0.05). CONCLUSION: BYD combined with TT, LC, and VESC could significantly improve sperm qualities and clinical Chinese medical symptoms of oligospermia patients of SEDS.
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Medicina Tradicional Chinesa/métodos , Oligospermia/terapia , Fitoterapia/métodos , Adulto , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Masculino , Oligospermia/diagnóstico , Adulto JovemRESUMO
Currently, the treatment of burns poses a significant challenge to clinical surgical. The use of nanofibers combined with drugs provides an entirely new option for treating burns. Alum-borneol combination has been shown as a promising alternative in clinical burn treatment. However, the utilization of the alum-borneol combination is not optimistic due to the low solubility of borneol. In this study, alum-borneol incorporated polyvinyl pyrrolidone fibers with a core-shell structure were fabricated through coaxial electrospinning. In vitro Borneol release behavior of fibers with different ratios of alum to borneol was explored. Scanning electron microscopy, transmission electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimeter, in vitro drug release, and in vitro release mechanism were evaluated. The results showed that the fiber membranes maintained an integrated morphology. In vitro dissolution data showed an improved solubility of borneol, which reached more than 82% at 240 min in alum-borneol fibers. It was 4.8 times higher than borneol powder, and the ratio of alum to borneol was 2:1 for the best results. Therefore, alum-borneol incorporated polyvinyl pyrrolidone fibers can significantly improve the dissolution rate of borneol, which opens up a new way for the combined application of the alum and borneol.
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Abnormal activation of SETBP1 due to overexpression or missense mutations occurs frequently in various myeloid neoplasms and associates with poor prognosis. Direct activation of Hoxa9/Hoxa10/Myb transcription by SETBP1 and its missense mutants is essential for their transforming capability; however, the underlying epigenetic mechanisms remain elusive. We found that both SETBP1 and its missense mutant SETBP1(D/N) directly interact with histone methyltransferase MLL1. Using a combination of ChIP-seq and RNA-seq analysis in primary hematopoietic stem and progenitor cells, we uncovered extensive overlap in their genomic occupancy and their cooperation in activating many oncogenic transcription factor genes including Hoxa9/Hoxa10/Myb and a large group of ribosomal protein genes. Genetic ablation of Mll1 as well as treatment with an inhibitor of the MLL1 complex OICR-9429 abrogated Setbp1/Setbp1(D/N)-induced transcriptional activation and transformation. Thus, the MLL1 complex plays a critical role in Setbp1-induced transcriptional activation and transformation and represents a promising target for treating myeloid neoplasms with SETBP1 activation.
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Environmental exposure to metals, including essential and nonessential elements, may be related to semen quality. Our goal was to explore the continuous relationship between seminal metals and sperm parameters. A restricted cubic spline (RCS) was applied to automatic selection criteria to ascertain the optimal smoothing degree. We recruited 841 male volunteers from Henan Province, China. Eighteen seminal metals, namely Al, Cr, Mn, Cu, Zn, Se, As, Ni, Cd, Pb, Co, V, Rb, Ag, Ba, TI, Fe, and Li, and 21 semen parameters were detected. Seminal malondialdehyde (MDA) was also detected to express oxidative stress. We revealed a non-linear relationship of the vanadium and chromium exposure to semen parameters. There were inverse 'U' shapes found between seminal Cr and sperm concentrations, total sperm count, and semen quality. The best semen quality was observed when the seminal Cr concentration was 5.05 ppb, and an increase or decrease in chromium concentration led to decreased semen quality. The V concentration was associated with reduced sperm concentration, total sperm count, normal morphology, and progressive motility at high doses (V > 0.58 ppb). Seminal MDA had a strong adverse association with sperm motility parameters, such as curve line velocity (VCL) (P < 0.001), straight line velocity (VSL) (P = 0.004), velocity of average path (VAP) (P < 0.001), and lateral head movement (ALH) (P = 0.001), whereas it was adversely associated with seminal Zn (ß [95% confidence interval (CI)], -0.28(-0.41-0.16), P < 0.001) after adjusting for confounding factors. Our findings represent the curves of the dose-response relationship between seminal Cr, seminal V, and semen quality, in which seminal MDA was a good indicator of sperm movement. These models provide new insight into the dose-relationship between metal exposure and semen quality, and further investigation is needed to validate this.
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Análise do Sêmen , Motilidade dos Espermatozoides , Humanos , Masculino , Contagem de Espermatozoides , Espermatozoides/fisiologia , VanádioRESUMO
The gas diffusion layer (GDL) is an important component in the proton exchange membrane fuel cell (PEMFC), and the main function of GDL is to transfer water and gas. This paper explores the effect of the gradient hydrophobicity of GDL on the proton exchange membrane fuel cell (PEMFC). The gradient GDL design uses two microporous layers (MPL). First, polytetrafluoroethylene (PTFE) : carbon black in MPL near the carbon paper side was fixed at 3 : 7, and then the content of PTFE : carbon black in MPL near the catalyst layer (CL) was set to 3 : 7, 2 : 8 and 1 : 9. Second, the fixed PTFE : carbon black in MPL near the carbon paper side was 2 : 8, and the PTFE : carbon black in MPL near CL was 2 : 8 and 1 : 9. We found that, when near the carbon paper side and PTFE : carbon black = 3 : 7, GDL can obtain good cell performance through gradient hydrophobic treatment. Moreover, when near the carbon paper side and PTFE : carbon black = 2 : 8, the cell performance did not change much after GDL gradient hydrophobic treatment. We found that when GDL is subjected to a gradient hydrophobic treatment, the content of PTFE and carbon black must be rationally allocated to obtain good water management capabilities.
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As a multifunctional platform, cyclodextrin capped gold nanoparticles (AuNP@CDs) have attracted extensive attention due to their advantages of high specific surface area and high loading capacity. AuNP@CDs have a core-shell structure, retaining the advantages of the two materials. AuNPs act as the support for the monolayer assembly of CDs. Some functional molecules can enter the hydrophobic cavity of CD through the host-guest interaction. In this brief review, we discuss the strategies for the synthesis of AuNP@CDs depending on the type and order of bonding. Their applications in drug delivery, catalysis, detection and bioimaging are highlighted. We hope to further stimulate AuNP@CD related research.
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Ciclodextrinas/química , Ouro/química , Nanopartículas Metálicas/química , Sistemas de Liberação de Medicamentos , Estrutura MolecularRESUMO
Mechanisms underlying the progression of Chronic Myeloid Leukemia (CML) from chronic phase to myeloid blast crisis are poorly understood. Our previous studies have suggested that overexpression of SETBP1 can drive this progression by conferring unlimited self-renewal capability to granulocyte macrophage progenitors (GMPs). Here we show that overexpression of Hoxa9 or Hoxa10, both transcriptional targets of Setbp1, is also sufficient to induce self-renewal of primary myeloid progenitors, causing their immortalization in culture. More importantly, both are able to cooperate with BCR/ABL to consistently induce transformation of mouse GMPs and development of aggressive leukemias resembling CML myeloid blast crisis, suggesting that either gene can drive CML progression by promoting the self-renewal of GMPs. We further identify Myb as a common critical target for Hoxa9 and Hoxa10 in inducing self-renewal of myeloid progenitors as Myb knockdown significantly reduced colony-forming potential of myeloid progenitors immortalized by the expression of either gene. Interestingly, Myb is also capable of immortalizing primary myeloid progenitors in culture and cooperating with BCR/ABL to induce leukemic transformation of mouse GMPs. Significantly increased levels of MYB transcript also were detected in all human CML blast crisis samples examined over chronic phase samples, further suggesting the possibility that MYB overexpression may play a prevalent role in driving human CML myeloid blast crisis development. In summary, our results identify overexpression of HOXA9, HOXA10, and MYB as critical drivers of CML progression, and suggest MYB as a key therapeutic target for inhibiting the self-renewal of leukemia-initiating cells in CML myeloid blast crisis patients.
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SETBP1 missense mutations have been frequently identified in multiple myeloid neoplasms; however, their oncogenic potential remains unclear. Here we show that expression of Setbp1 mutants carrying two such mutations in mouse bone marrow progenitors efficiently induced development of acute myeloid leukemias (AMLs) in irradiated recipient mice with significantly shorter latencies and greater penetrance than expression of wild-type Setbp1, suggesting that these mutations are highly oncogenic. The increased oncogenicity of Setbp1 missense mutants could be due in part to their capability to drive significantly higher target gene transcription. We further identify Myb as a critical mediator of Setbp1-induced self-renewal as its knockdown caused efficient differentiation of myeloid progenitors immortalized by wild-type Setbp1 and Setbp1 missense mutants. Interestingly, Myb is also a direct transcriptional target of Setbp1 and Setbp1 missense mutants as they directly bind to the Myb locus in immortalized cells and dramatically activate a critical enhancer/promoter region of Myb in luciferase reporter assays. Furthermore, Myb knockdown in Setbp1 and Setbp1 missense mutations-induced AML cells also efficiently induced their differentiation in culture and significantly prolonged the survival of their secondary recipient mice, suggesting that targeting MYB pathway could be a promising strategy for treating human myeloid neoplasms with SETBP1 activation.
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Proteínas de Transporte/fisiologia , Leucemia Mieloide Aguda/etiologia , Proteínas Nucleares/fisiologia , Proteínas Proto-Oncogênicas c-myb/fisiologia , Animais , Proteínas de Transporte/genética , Feminino , Proteínas Homeobox A10 , Proteínas de Homeodomínio/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos C57BL , Mutação de Sentido Incorreto , Proteínas Nucleares/genética , Proteínas Proto-Oncogênicas c-myb/antagonistas & inibidoresRESUMO
Long-term hematopoietic stem cells (LT-HSCs) have the ability to self-renew and differentiate into all blood cell lineages. Understanding the genetic networks that regulate LT-HSC function in the adult bone marrow requires inducible gene targeting and bone marrow transplantations. In this chapter we describe the use of the inducible Mx1-Cre mouse model to delete genes in LT-HSCs and methodologies for examining the function of LT-HSCs following deletion.