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OBJECTIVE: To evaluate the possible association between radon exposure and kidney cancer. METHODS: We performed a systematic review and a meta-analysis based on random effect models to provide a pooled association measure. RESULTS: We subjected 8 studies (overall relative risks and 95% confidence intervals: 1.01, 0.72 to 1.43, I2 = 64.4%) to meta-analysis. Subgroup analysis revealed a marginally significant association between radon exposure and kidney cancer in studies conducted in Europe. Two population-based studies provided no evidence for the increased risk of kidney cancer in the general population. CONCLUSION: The association between radon and kidney cancer remains unclear but cannot be excluded because of its biological plausibility and the limited number and quality of existing studies. Additional data from the general population and well-designed miner cohort studies are needed to reveal the real relationship between radon exposure and kidney cancer.
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Neoplasias Renais/etiologia , Radônio/toxicidade , Estudos de Coortes , Exposição Ambiental/efeitos adversos , HumanosRESUMO
Metallic Ni3 P/Ni can be used as a co-catalyst to replace noble metal Pt for efficient photocatalytic hydrogen evolution, due to its excellent trapping-electron ability. The applications of metallic Ni3 P/Ni co-catalyst on CdS, Zn0.5 Cd0.5 S, TiO2 (Degussa P25) and g-C3 N4 are further confirmed, indicating its versatile applicability nature like Pt.
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Objective: Hemifacial spasm (HFS) is a common neurological disorder of the brain, which is difficult to treat. Most patients are distracted by it and are unable to work or study normally, which seriously affects their physical and mental health. However, there are a few bibliometric studies on it. This paper searched the articles on HFS using a bibliometric approach. Method: Articles about HFS were retrieved from the Web of Science (WoS) Core Collection database. We employed the Visualization of Similarities (VOS)viewer to analyze these publications. Results: A total of 645 reviews or articles in English were retrieved from WoS. In this study, we found that the number of publications showed a rising trend and China is the most active in searching the treatment of HFS. About keywords, neurosciences and neurology was searched (422 times) keyword, followed by hemifacial spasm (420 times) and surgery (320 times). By assessing the organizations, Shanghai Jiao Tong University published the most papers (8.68%), followed by Sungkyunkwan University (3.26%) and Baylor College Medicine (2.64%). A total of 247 journals have delivered publications on the treatment of HFS, World Neurosurgery (44 papers) published the largest number of articles. Conclusion: The annual publications have increased with a fluctuating tendency. More researchers were taking an interest in HFS. This study helped us find out the hotspot and trend in research about facial spasm treatment.
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Idiopathic pulmonary fibrosis (IPF) is an interstitial pulmonary disease with an extremely poor prognosis. Autophagy is a fundamental intracellular process involved in maintaining cellular homeostasis and regulating cell survival. Autophagy deficiency has been shown to play an important role in the progression of pulmonary fibrosis. This review focused on the six steps of autophagy, as well as the interplay between autophagy and other seven pulmonary fibrosis related mechanisms, which include extracellular matrix deposition, myofibroblast differentiation, epithelial-mesenchymal transition, pulmonary epithelial cell dysfunction, apoptosis, TGF-ß1 pathway, and the renin-angiotensin system. In addition, this review also summarized autophagy-related signaling pathways such as mTOR, MAPK, JAK2/STAT3 signaling, p65, and Keap1/Nrf2 signaling during the development of IPF. Furthermore, this review also illustrated the commonly used autophagy detection methods, the currently approved antifibrotic drugs pirfenidone and nintedanib, and several prospective compounds targeting autophagy for the treatment of IPF.
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Fibrose Pulmonar Idiopática , Humanos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Proteína 1 Associada a ECH Semelhante a Kelch , Estudos Prospectivos , Fator 2 Relacionado a NF-E2 , AutofagiaRESUMO
Phenol and its chemical derivatives serve as essential chemical materials are indispensable for the synthesis of many kinds of polymers. However, they are highly toxic, carcinogenic, difficult to be degraded biologically, and often found in aqueous effluents. Recovery of hazardous phenol from wastewater remains a daunting challenge. Herein, we prepared a hybrid membrane containing polyether block amide (PEBA) matrix and HZIF-8 fillers. To improve the compatibility between ZIF-8 and PEBA, ZIF-8 was modified by using polystyrene (PS) as a template to prepare porous HZIF-8. ZIF-8, composed of zinc nodes linked by the imidazole ring skeleton, is a kind of inorganic material with high hydrothermal stability, ordered pores, and hydrophobic microporous surfaces, which has a wide range of applications in membrane separation. The separation performance of the PEBA/HZIF-8 based membranes for phenol/water is improved due to the presence of PS on the surface of HZIF-8 and the imidazole ring skeleton in ZIF-8, which enhance the π-π interaction between HZIF-8 and phenol molecules. The effects of HZIF-8 content, feed phenol concentration, and feed temperature on the pervaporation performance of PEBA/HZIF-8 membranes were further investigated. The results showed that the pervaporation performance of the PEBA/HZIF-8-10 membrane was promising with a separation factor of 80.89 and permeate flux of 247.70 g/m2·h under the feed phenol concentration of 0.2 wt % at 80 °C. In addition, the PEBA/HZIF-8-10 membrane presented excellent stability, which has great prospect for practical application in phenol recovery from waste water.
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A two-dimensional molybdenum disulfide (MoS2) nanosheet, as a new type of inorganic material with high hydrophobicity and excellent physicochemical stability, holds great application potential in the preparation of a high separation performance organic-inorganic hybrid membrane. In this work, high hydrophobic MoS2 was embedded in hydrophobic polyether copolymer block amide (PEBA) to prepare PEBA/MoS2 organic-inorganic hybrid membranes. The structure, morphology, and hydrophobicity of the hybrid membrane were characterized by scanning electron microscopy, thermogravimetric analysis, contact angle goniometry, X-ray diffraction, infrared spectroscopy analysis, and atomic force microscopy. The effect of embedding of MoS2 on the swelling degree and pervaporation separation performance of the PEBA/MoS2 hybrid membrane was studied with a 1.0 wt % pyridine dilute solution. The results indicated that with increasing the MoS2 content, the separation factor of PEBA/MoS2 increased first and then decreased, while it showed a downward trend in the permeation flux. When the MoS2 content in the PEBA/MoS2 hybrid membrane was 10.0 wt %, the permeation flux was 83.4 g m-2 h-1 (decreased by 21.5% compared with the pure PEBA membrane), and the separation factor reached a maximum value of 11.11 (increased by 37.6% compared with the pure PEBA membrane). Meanwhile, the effects of feed temperature on the pervaporation separation performance of PEBA/MoS2 hybrid membranes were also studied. In addition, as the PEBA/MoS2 hybrid membrane has excellent thermal stability, it is expected to be a promising material for recovering pyridine from wastewater.
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The length of Lelecella limenitoides complete mitogenome was 15,203 bp and contained the typical gene arrangement, base composition, and codon usage found in other related species. The overall base composition exhibited obvious anti-G (7.5%) and AT bias (81.6%). The initiation codons of all PCGs were typical ATN (ATA/ATG/ATT), and the termination codons were TAA, TAG, or incomplete stop codon T-. All tRNAs could be folded into typical cloverleaf secondary structures, except tRNASer (AGN). Phylogenetic analysis showed that L. limenitoides was clustered with the clade of Sasakia, Euripus, and Apatura.
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More and more studies have demonstrated that bone marrow microenvironment, the fundament of the multiplication and differentiation of hematopoietic stem cells, plays a crucial role in leukemia progression and resistance to treatment. It provides a permissive environment for minimal residual disease and contributes to relapse and multidrug resistance. Mesenchymal stem cells are a kind of important stromal cells in bone marrow niche. In recent researches, MSC have been shown to be one of the major factors modulating the biological features of leukemia cells. The cross-talk between MSC and leukemia cells can take place not only by direct contact, but also by exosome exchange. Exosomes are nano-sized vesicles released by a variety of cells, which contain protein, RNA and mRNA. They are effective tools for transportation between cells, and play an important role in many physiological and pathological processes. Exosome is a new topic in the research of leukemia and microenvironment. The exosome research will help elucidate the mechanism of leukemia, thus providing new ideas for the treatment.
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Exossomos , Leucemia , Células-Tronco Mesenquimais , Medula Óssea , Células-Tronco Hematopoéticas , HumanosRESUMO
The atomically controlled transition of nanohybrids and their effects on charge-carrier dynamics are highly desirable for fundamental studies in photocatalysis. Herein, for the first time, a method combining atomic monodispersity and single-atom alloy was used to prepare a new form of highly efficient silver-based cocatalysts (Ag25 & Pt1Ag24) on graphitic carbon nitride, representing a novel photocatalytic system for hydrogen evolution.
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Facilitating charge-carrier separation and transfer is fundamentally important to improve the photocatalytic performance of semiconductor materials. Herein, two-dimensional hexagonal WO3 nanoplates were synthesized by a two-step route: rapid evaporation and solid-phase sintering. The as-prepared WO3 exhibits an enhanced activity of photocatalytic water oxidation compared to bulk monoclinic WO3 . The electron dynamics analysis reveals that a more efficient charge-carrier separation in the former can be obtained, the origin of which can be attributed to an increased number of surface defects in hexagonal WO3 nanoplates. This work not only presents a novel and simple method to produce two-dimensional hexagonal WO3 nanoplates, but also demonstrates that surface defects and two-dimensional geometric structures can promote the charge separation, which may be extended to the design of other efficient photocatalysts.
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Chronic myeloid leukemia (CML) is a disease originated from malignant hematopoietic stem cell disorder. In CML, mesenchymal stem cells(MSC) have been changed in the bone marrow microenvironment, which can protect the leukemia cells from apoptosis induced by tyrosine kinase inhibitors (TKI) and lead to the resistance to TKI by the secretion of soluble factors, involvement in cell-cell adhesion, and so on. This review mainly focuses on the changes of the bone marrow mesenchymal stem cells in CML, as well as the role and mechanism of MSC in the CML resistance of TKI. The concrete probrems dicussing in this review are role of MSC in bone marrow microenviroment, characteristics of MSC in CML, the related mechanisms of MSC in drug resistance and so on.
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Resistencia a Medicamentos Antineoplásicos , Células-Tronco Mesenquimais , Apoptose , Medula Óssea , Células-Tronco Hematopoéticas , Humanos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Proteínas Tirosina QuinasesRESUMO
Porous oxygen-doped graphitic carbon nitride (g-C3N4) with feeble nitrogen vacancies was fabricated through thermal polycondensation of melamine with an appropriate amount of polyvinylpyrrolidone. After optimization, the bandgap of g-C3N4 can be narrowed by 0.2 eV and the specific surface area expanded, which contribute to increasing the utilization of solar energy. Consequently, the optimized g-C3N4 exhibits impressive enhancement in photocatalytic hydrogen evolution performance, by nearly 5 times compared with the pristine one under the irradiation of visible light.
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Although the tyrosinekinase inhibitors (TKI) displayed a significant curative effect on chronic myeloid leukemia (CML), but the drug resistance in treatment course of this disease still can not be avoided. Studies recently have shown that the mesenchymal stem cells (MSC) can induce CML cells to resist TKI therapy by CXCL12/CXCR4 axis from multiple aspects, such as the directional migration of CML cells, adherence to marrow cavity, the mediation of cell protective dormancy, activations of numerous survival signaling pathways, the suppression of mitochondrial-dependent apoptosis and the up-regulated expression of BCL-6. The combination of TKI and CXCR4 antagonists will be a novel treatment strategy to raise the genetic cure rate of CML. In this article, the pathways of drug resistance, pathways of sensitivity to CXCL12 and pathways of CML cell adherence to marrow cavity in CML cells mediated by MSC were reviewed.
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Resistencia a Medicamentos Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Transdução de Sinais , Células-Tronco , Humanos , Inibidores de Proteínas Quinases , Proteínas Tirosina QuinasesRESUMO
OBJECTIVE: To explore the effects of bone marrow mesenchymal stem cells (MSCs) on the quality of healing of porcine skin wounds after burn injury so as to provide a new method for clinical skin repair in the future. METHODS: Seventy-two deep-partial thickness burn wounds were produced on the back of 6 minipigs and then the pigs were randomly divided into 6 groups: saline control, MSCs treatment, MSCs plus basic fibroblast growth factor (bFGF) treatment, MSCs plus epidermal growth factor (EGF) treatment, bFGF treatment or EGF treatment only. MSCs were isolated from porcine marrow and cultured in vitro. After labeling with BrdU, MSCs were autografted onto the skin wounds. 7, 14, 21 and 42 days after the injury, the area of the wounds were measured and the histological examination was performed to evaluate the velocity and quality of wound healing.1, 2 and 4 weeks after transplantation, immunohistochemical examinations were carried out to detect the positive staining of BrdU, cytokeratin and S-100 to evaluate the wound healing quality. RESULTS: The area of wounds was decreased at day 7 and most of these wounds were healed on day 21 after injury. Although there was no significant statistical difference in the contraction rate among these six groups, however, the reduced wound areas in the MSCs plus bFGF treatment group was 15% to 20% more than that in the other 5 groups. Histological examination and semi-quantitative analysis demonstrated that the number of vessels and the expression density of S-100 in the MSCs plus bFGF treatment wounds were significantly enhanced than that in the other groups. CONCLUSION: MSCs autografting may benefit to enhance the wound healing quality in porcine skin, which may open a new way to reach a "perfect repair" after skin injury.
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Queimaduras/cirurgia , Transplante de Células-Tronco Mesenquimais/métodos , Pele/patologia , Cicatrização , Animais , Células da Medula Óssea/citologia , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Fator 2 de Crescimento de Fibroblastos/farmacologia , Masculino , Pele/metabolismo , Suínos , Porco Miniatura , Cicatrização/efeitos dos fármacosRESUMO
OBJECTIVE: To investigate the feasibility of differentiation of bone marrow mesenchymal stem cells (MSCs) into skin appandence. METHODS: Porcine MSCs were isolated from porcine marrow and grown in vitro. After labeling with BrdU, MSCs were engrafted to porcine skin. At 1, 2, 4 weeks after the transplantation, immunohistochemical examinations were carried out to detect the positive staining of BrdU and cytokeratin. RESULTS: A few sebaceous duct cells, which expressed cytokeratin, were also BrdU positive, and these cells were considered may to be transplanted MSCs-derived cells. CONCLUSION: Porcine MSCs might have the potential to differentiated into sebaceous duct cells in skin.
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Células da Medula Óssea/citologia , Diferenciação Celular , Células-Tronco Mesenquimais/citologia , Glândulas Sebáceas/citologia , Animais , Transplante de Células-Tronco Mesenquimais , Suínos , Porco Miniatura , Transplante AutólogoRESUMO
OBJECTIVE: To establish a method for the isolation of porcine mesenchymal stem cells (MSCs) from bone marrow and to demonstrate their differentiation ex vivo into various mesenchymal tissue cells. METHODS: MSCs were isolated from bone marrow and purified by centrifuge and in vitro. The proliferation and growth characteristics were observed in primary and passage culture. Cell cycle was analyzed by measuring DNA content with FAC-Scan flow cytometer and cell multipotent was identified with specific staining. RESULTS: The adherent, fibroblast-like cells were confluent in single layer after plating for 12-14 days. The cultured MSCs in vitro differentiated into osteoblasts. The cell cycle analysis showed that 80% of MSCs were in G0/G1 phase. CONCLUSION: Porcine MSCs can be isolated from postnatal bone marrow through their adherent ability. Porcine MSCs may be introduced as a valuable model system to study the mesenchymal lineages for basic research and tissue engineering.
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Células da Medula Óssea/citologia , Separação Celular/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Multipotentes/citologia , Animais , Ciclo Celular , Diferenciação Celular , Células Cultivadas , Citometria de Fluxo , Suínos , Engenharia TecidualRESUMO
Butterfly is an important bio-indicator for biodiversity monitoring and ecological environment assessment. In Europe, the species composition, population dynamics, and distribution pattern of butterfly have been monitored for decades, and many long-term monitoring schemes with international effects have been implemented. These schemes are aimed to assess the regional and national variation trends of butterfly species abundance, and to analyze the relationships of this species abundance with habitat, climate change, and other environmental factors, providing basic data for researching, protecting, and utilizing butterfly resources and predicting environmental changes, and playing important roles in the division of butterfly' s threatened level, the formulation of related protection measures, and the protection and management of ecological environment. This paper reviewed the history and present status of butterfly monitoring in Europe, with the focus on the well-known long-term monitoring programs, e. g. , the UK Butterfly Monitoring Scheme and the Germany and European Union Butterfly Monitoring Scheme. Some specific proposals for conducting butterflies monitoring in China were suggested.
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Biodiversidade , Borboletas/fisiologia , Mudança Climática , Ecossistema , Monitoramento Ambiental/métodos , Animais , Borboletas/classificação , China , Conservação dos Recursos Naturais , Europa (Continente) , Dinâmica PopulacionalRESUMO
An investigation was conducted on the butterflies on the south slope of Taibai Mountain from April to October, 2009, with their diversity index, evenness index, dominance index, and species richness calculated and analyzed. A total of 126 species were recorded, belonging to 77 genera and 5 families. Nymphalidae had the highest diversity index (3.3621) and species richness (9.9363), and Pieridae had the highest dominance index (0.0573) and evenness index (0.8352). The genera and species were most abundant in June-August, the diversity index was the highest in July (3.4094), and the species richness was the highest in August (10.7). The bio-geographic component analysis of 124 species (other 2 species were not identified) showed that the widely distributed species were most abundant (51 species), occupying 40.5% of the total, followed by Palaearctic species (41 species), occupying 32.5%, and Oriental species were the least (32 species), occupying 25.4%, which suggested that Taibai Mountain could be the transitional area of Palearctic and Oriental regions. The comparative analysis of the butterfly diversity and faunal characteristics on the south and north slopes of Taibai Mountain showed that there were 85 shared species, and the similarity coefficient was 62.0%, indicating that the butterfly fauna had definite difference between the two slopes though they were geographically in proximity.
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Biodiversidade , Borboletas/classificação , Conservação dos Recursos Naturais , Ecossistema , Animais , Borboletas/crescimento & desenvolvimento , China , Dinâmica PopulacionalRESUMO
PURPOSE: To investigate the expression of MMP-2 in porcine bone marrow mesenchymal stem cells (MSCs) in the process of differentiation into vascular endothelial cells in vitro. METHODS: Porcine MSCs were isolated from bone marrow and grown in vitro. At 3-, 7-day after VEGF induction, immunohistochemical and flow cytometrical examinations were carried out to detect the staining of FVIII. The expression of MMP-2 was analyzed by Western blot. RESULTS: At 3-, 7-day after VEGF induction, the morphology of the cells gradually changed. The cells gradually showed a ball-like appearance at 3-day. They connected with adjacent cells and formed tube-like structure after 7 days. The factor VIII-positive cells could be observed at 3-day after VEGF induction. The positive cells increased and joined to neighboring FVIII-positive cells, formed tube-like structures at 7-day after VEGF treatment. MSCs maintained in control medium stained negative. FACS analysis showed that untreated MSCs were negative for FVIII. The number of FVIII positive cells was not significantly increased at 3-day after induction (3%). But at 7-day after induction, FVIII-positive cells were significantly increased (13%). The expression of MMP-2 was increased as early as 1 hour post VEGF treatment. CONCLUSION: Porcine MSCs have the potential to differentiate into vascular endothelial cells in vitro and this process involves MMP-2.
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Diferenciação Celular , Metaloproteinase 2 da Matriz , Células-Tronco Mesenquimais , Animais , Células da Medula Óssea , Células Endoteliais , SuínosRESUMO
OBJECTIVE: Hepatitis B has been extensively prevalent in China and hepatitis B virus associated nephritis (HBV-GN) has been one of the common renal damages secondary to HBV infection in Chinese children. Regular vaccination against hepatitis B has been carried out nation-wide in China since January 1st, 1992. The present study was conducted to evaluate the effect of regular vaccination against hepatitis B virus on the incidence of childhood HBV-GN and membranous nephropathy (MN). METHODS: Retrospective analysis on the results of renal biopsy in 727 patients (from Nov. 1979 to March 2002) was carried out. The patients were first divided into two groups according to the date when the patients were seen. Group A patients were seen from Nov. 1979 through Dec. 1991; Group B patients were seen from Jan. 1992 through March 2002. Group B patients were further divided into 5 subgroups (Group B(1) to B(5)), with a 2-year interval after 1992. Secondly, each of these groups and subgroups were again divided into two groups, vaccinated and unvaccinated groups. RESULTS: In 727 renal biopsies, 64 cases (8.80%) met HBV-GN diagnostic criteria. Twenty-eight cases were diagnosed as HBV-GN in Group A (211 cases), accounting for 13.27%, while there were 36 cases with HBV-GN in 516 renal biopsies of Group B, accounting for 6.98% (chi(2) = 7.397 and P < 0.01). The frequency in Group B was significantly lower. Prevalence rate (from Group A to Group B(5)) was 13.3% (28/211), 13.0% (9/69), 7.3% (6/82), 6.3% (4/64), 4.9% (4/82), 5.9% (13/219), respectively, which showed a tendency of decline. Only 8 cases of HBV-GN occurred in vaccinated group (231 cases), accounting for 3.5%, while 48 cases of HBV-GN were seen in unvaccinated group (381 cases), accounting for 12.6% (chi(2) = 14.44 and P < 0.001), vaccination history was unknown in 115 of the 727 cases. In 727 renal biopsies, pathological type of 46 cases (6.3%) was membranous nephropathy and all of them had HBV-GN. Six cases of MN occurred in vaccinated group, accounting for 2.60%, while 40 cases with membranous nephropathy were found in unvaccinated group, accounting for 10.5% (chi(2) = 12.92 and P < 0.001). On the other hand, in vaccinated group there still were 8 cases of HBV-GN whose serum markers of HBV were positive. Two of their mothers had apparent evidence of hepatitis B virus infection. CONCLUSION: The frequency of HBV-GN has decreased significantly after vaccination against hepatitis B virus was routinely carried out since 1992; at the same time, childhood membranous nephropathy might be decreasing gradually, too. The cause of individual cases of HBV-GN who has be vaccinated was probably due to maternal-infant transmission and immunization failure. Attention should be paid to interruption of maternal-infant transmission and serological follow-up should be performed in high-risk newborns after vaccination to further lower the incidence of hepatitis B virus associated nephritis.